doi.org/10.26434/chemrxiv.13667807.v2

Mechanism of 8-Aminoquinoline Directed Ni-Catalyzed C(sp3)-HFunctionalization: Paramagnetic Ni(II) Species, and the DeleteriousEffect of Na2CO3 as a BaseJunyang Liu, Samuel Johnson

Submitted date: 02/02/2021 • Posted date: 03/02/2021Licence: CC BY-NC-ND 4.0Citation information: Liu, Junyang; Johnson, Samuel (2021): Mechanism of 8-Aminoquinoline DirectedNi-Catalyzed C(sp3)-H Functionalization: Paramagnetic Ni(II) Species, and the Deleterious Effect of Na2CO3as a Base. ChemRxiv. Preprint. https://doi.org/10.26434/chemrxiv.13667807.v2

Studies into the mechanism of 8-aminoquinoline-directed nickel-catalyzed C(sp3)–H arylation with iodoarenesare described, in an attempt to determine the catalyst resting state and optimize catalytic performance.Paramagnetic complexes are identified that are undergo the key C–H activation step. Hammett analysis usingelectronically different aryl iodides suggests a concerted oxidative addition mechanism for the C–Hfunctionalization step; DFT calculations were also performed to support this finding. When Na2CO3 is used asthe base the rate determination step for C–H functionalization appears to be 8-aminoquinoline deprotonationand binding to Ni. The carbonate anion was also observed to provide a deleterious NMR inactive low-energyoff-cycle resting state in catalysis. Replacement of Na2CO3 with NaOtBu not only improved catalysis at milderconditions but also eliminated the need for carboxylic acid and phosphine additives.

File list (2)

download fileview on ChemRxivMechanism_Ni_CH_arylation_SJ.pdf (1.37 MiB)

download fileview on ChemRxivSI_Mechanism_Ni_CH_arylation_SJ.pdf (5.47 MiB)

1

Mechanism of 8-Aminoquinoline Directed Ni-

Catalyzed C(sp3)-H Functionalization:

Paramagnetic Ni(II) Species, and the Deleterious

Effect of Na2CO3 as a Base.

Junyang Liu, and Samuel A. Johnson*

Department of Chemistry and Biochemistry, University of Windsor, Sunset Avenue 401,

Windsor, ON, N9B 3P4, Canada

ABSTRACT

Studies into the mechanism of 8-aminoquinoline-directed nickel-catalyzed C(sp3)–H

arylation with iodoarenes were performed, in an attempt to determine the catalyst resting

state and optimize catalytic performance. Paramagnetic complexes are identified that are

undergo the key C–H activation step. The ubiquitous base Na2CO3 is found to hinder

catalysis; replacement of Na2CO3 with NaOtBu gave improved catalytic turnovers under

milder conditions. Deprotonation of the 8-aminoquinoline derivative N-(quinolin-8-

yl)pivalamide (1a) at the amide nitrogen using NaH, followed by reaction with

NiCl2(PPh3)2 allowed for the isolation of complex Ni([AQpiv]-κN,N)2 (3) with chelating

N-donors, (where [AQpiv] = C9NH6NCOtBu). Complex 3 is a four-coordinate

disphenoidal high-spin Ni(II) complex, excluding short anagostic Ni--tBu hydrogen

interactions. Complex 3 undergoes reaction with paddle-wheel [Ph3PNi(-CO2tBu)2]2

(6·PPh3) or tBuCO2H to give insoluble {[AQpiv]Ni(O2CtBu)}2 (5). Dissolution of 5 in

donor solvents L (L= DMSO, DMF) gave a new paramagnetic intermediate assigned by

NMR as [AQpiv]Ni(O2CtBu)L (5·L) and equilibrium reformation of 3 and 6·L. DFT

calculations support this equilibrium in solution. Both 3 and 5 undergo C–H activation at

temperatures as low as 80 °C and in the presence of PR3 (PR3 = PPh3, PiBu3) to give

Ni(C9NH6NCOCMe2CH2-κN,N,C)PR3 (7·PR3). The C–H functionalization reaction

orders with respect to 7·PiBu3, iodoarenes, and phosphines were determined. Hammett

analysis using electronically different aryl iodides suggests a concerted oxidative addition

mechanism for the C–H functionalization step; DFT calculations were also performed to

support this finding. When Na2CO3 is used as the base the rate determination step for C–

H functionalization appears to be 8-aminoquinoline deprotonation and binding to Ni.

The carbonate anion was also observed to provide a deleterious NMR inactive low-

energy off-cycle resting state in catalysis. Replacement of Na2CO3 with NaOtBu not only

2

improved catalysis at milder conditions but also eliminated the need for carboxylic acid

and phosphine additives.

INTRODUCTION

The functionalization of C–H bonds provides an atom efficient way to construct new

bonds to carbon. Transition metal complexes are often employed as catalysts to effect C–

H bond transformations, with the precious metals often yielding the most active catalysts.1-

6 The use of abundant first-row transition metal catalysts in lieu of precious metals has

received widespread attention, due to reduced cost and environmental benefits.7 However,

the first row transition metals often feature decreased reactivity and selectivity in the

functionalization of unactivated C(sp3)–H bonds.8

Among the strategies developed to overcome these challenges,9 one of the most

successful methods is the installation of a directing group on the target molecule to aid

selective C–H activation.10 An early example is the nickelocene mediated C–H activation

of one of ortho C–H bond of azobenzene.11 In the 1990s, Chatani reported the Ru-catalyzed

addition of alkenes to the ortho C–H of aromatic ketones.12 Seminal work done by Daugulis

et al. in 2005 showed that N, N-bidentate directing groups such as 8-aminoquinoline (8-

AQ) could be used to enhance the selectivity of Pd-catalyzed functionalization of C–H

bonds.13 In 2011, Chatani et al. demonstrated the first example of a Ni-catalyzed 8-

aminoquinoline-directed C(sp2)–H alkynylation reaction.14 Related works soon followed,

including C–C(sp)/C(sp2)/C(sp3)15-36 and C–heteroatom bond formation.15, 37-49

The activation of the weaker C–H bonds of alkyl groups is typically more difficult

for Ni than the stronger aromatic C–H bonds. The first example employing 8-

aminoquinoline as a directing group in the more difficult Ni-catalyzed C(sp3)—H

functionalization was not reported in literature until 2014,16 and used aryl iodides as

coupling partners. Although the mechanism of Pd-catalyzed C(sp3)—H functionalization

reactions are well studied,50-52 less is known about the possible differences in Ni-catalyzed

systems. An understanding of the catalytic cycle and its elementary steps are crucial for the

3

designing of new catalyst systems with improved selectivity and efficiency. Multiple

mechanisms have been suggested for Ni-catalyzed C(sp3)—C bond formation, including

oxidative addition and radical pathways shown in Scheme 1a and 1b. DFT calculations

have suggested that both mechanisms are operational depending on the nature of the

substrates.53-54 Love and co-workers published a study on the C—H activation step using

an 8-aminoquinoline (8-AQ) functionalized tertiary urea as the model substrate and

isolated a Ni(II) ureate complex with a C—Ni bond, shown in Scheme 1c.55 The

intramolecular C—H activation is suggested to go through a concerted metalation

deprotonation mechanism with an electrophilic C—H activation transition state, as

supported by Hammett plot and KIE studies;55 however, no intermediates prior to C—H

activation or functionalization steps have been isolated. DFT studies suggest a

diamagnetic Ni(II) complex prior to C—H activation as the catalytic resting state shown

in Scheme 1c,54 but no experimental attempt to verify this theoretical prediction has been

reported, to date.

4

Scheme 1. (a) General reaction scheme of 8-aminoquinoline assisted Ni(II)-catalyzed

C(sp3)—H functionalization. (b) Proposed mechanisms based on previous computational

studies. (c) Isolated analogue of catalytically-relevant intermediate and DFT proposed

diamagnetic catalyst resting state.

Herein, we report a mechanistic study of 8-aminoquinoline directed, Ni-catalyzed C(sp3)

—H arylation with aryl halides with the identification and isolation of unexpected mono-

and dinuclear paramagnetic nickel intermediates. The results suggest a more complex

5

mechanistic manifold involving paramagnetic intermediates, and a reconsideration of the

rate-determining step in this catalytic functionalization, which counter to DFT predictions

involves neither of the expected C—H activation nor Ni(II)-Ni(IV) oxidative addition, but

rather the deprotonation step, when Na2CO3 is used as the base . Furthermore, Na2CO3

proves not only to be an insufficient base, but evidence suggests the carbonate anion forms

an off-cycle resting state that is detrimental to catalyst performance, and replacement with

NaOtBu leads to more efficient catalysis.

RESULTS AND DISCUSSION

Ligand Coordination. Attempts were made to coordinate N-(quinolin-8-yl)pivalamide,

abbreviated [AQpiv]H (1a), to a variety of Ni(II) sources, to generate a Ni(II) complex prior

to C—H bond activation. Under catalytic conditions, the ligand coordination step has been

proposed to proceed through base-mediated deprotonation of the amido nitrogen, to

generate the anionic ligand precursor [AQpiv]Na (2a), followed by a transmetallation with

Ni(II) salts. However, the reaction between 1a and NiX2 sources in refluxing THF or

toluene (X = OTf, Cl, Br, I , and acetylacetonate) in the presence of excess Na2CO3

provided no observable reaction. Similarly, the reaction with Na2CO3 showed no evidence

for the deprotonation of 1a under these conditions; however, the stronger base NaH gave

quantitative conversion to the isolable sodium salt 2a, as shown on the top of Scheme 2.

The sodium salt 2a is insoluble in THF, and was characterized by NMR spectroscopy in

DMSO.

6

Scheme 2. Synthesis of sodium salt [AQpiv]Na (2a) and reaction to give Ni[AQpiv]2 (3).

Complex 4 was not observed by 1H NMR, irrespective of reaction stoichiometry.

Salt metathesis between 2a and NiCl2(PPh3)2 in toluene led exclusively to the formation

of the dark brown paramagnetic complex [AQpiv]2Ni (3), as shown in the bottom of Scheme

2. The reaction was monitored by 1H NMR, and the conversion was practically quantitative

within 30 minutes at room temperature. Analogous reactions with other Ni(II) precursors

such as NiCl2(PiBu3)2 or NiCl2 also provided 3, but these reactions required 12 h to go to

completion. Complex 3 is pentane insoluble and was crystallized from toluene at –40 °C

Although the mono-ligated complex [AQpiv]NiCl (4) is related to key intermediates in

proposed catalytic cycles, it was not observed in these reactions. Even using

substoichiometric 2a (e.g. 0.5 equiv) only complex 3 was observed. This is almost

certainly due to the thermodynamic instability of 4 with respect to ligand redistribution to

give 3.

Paramagnetic Ni(II) complexes are often observable by 1H NMR, and the spectrum

of 3 is typical for a paramagnetic species. The chemical shifts for 3 span from 5-220 ppm,

and all the resonances are broad singlets. The 1H NMR peak at δ 64 is readily assigned as

the tBu group due to its integration to 18 H. The 13C NMR peak assigned to the tBu Me

7

groups was observed at δ 622.6. The magnetic moment (μeff) of 3 was determined to be

3.31 μB by Evan’s method at 298 K in benzene-d6, which corresponds to a high spin Ni(II)

bearing two unpaired electrons with spin-orbit coupling (S=1, spin only μeff = 2.83 μB).

Single crystal X-Ray diffraction provided structural data for 3, and an ORTEP depiction

in shown in Figure 1. The nickel center adopts a rare seesaw geometry; only a few

examples of disphenoidal Ni(II) complexes are known.56-59 There are few relevant

structurally characterized examples of complexed 8-aminoquinoline ligand moieties where

the ligand has not already undergone C-H activation. Previously, phenyl C(sp2)—H

activated complexes have been isolated as penta-coordinated complexes with one C(sp2)—

H bond activated for Ni and Co-catalyzed systems.60-62 A single Cu(II) complex in known

without activation for Bis[N-(quinolin-8-yl)benzamidato-κ2N,N']copper(II).63

Ni(1)

N(1)

N(2)

N(4)

N(3)

C(3)C(13)

O(1)

O(2)

H3a

Figure 1. ORTEP depiction of 3 (CCDC 2055354) with 30% thermal ellipsoids.

Hydrogens except the one closest to Ni were omitted for clarity. Selected bond lengths

(Å): Ni(1)–N(1) 1.981(1), Ni(1)–N(2) 1.982(1), Ni(1)–N(3) 1.983(1), Ni(1)–N(4)

1.974(1), Ni(1)–H(3a) 2.17. Selected bond angles (deg): N(1)–Ni(1)–N(3) 165.88(6),

N(3)–Ni(1)–N(4) 84.13(5), N(1)–Ni(1)–N(2) 84.28(6), N(2)–Ni(1)–N(4) 95.29(6).

Notable in the structure is the close proximity between Ni(1) and H(3a) on the tBu

group, which is only 2.17 Å . This short contact is drawn as a red dashed line in Figure 1.

The second tBu group features a second contact with a slightly longer distance of 2.32 Å.

If there were attractive agostic interactions with both tBu groups, complex 3 would be

octahedral; however, all evidence suggests that these are anagostic interactions. The IR

8

spectrum of 3 shows show no reduced C(sp3)—H stretching mode. The tBu resonance

gave a single signal in the 1H NMR at temperatures as low as 193 K, though this could

arise from a rapid fluxional process where each methyl hydrogen in each methyl group on

the tBu substituents adopt the agostic position.64 Equilibrium isotope effects should be very

sensitive in this paramagnetic system. As shown in Scheme 3, complex [AQpiv-d3]2Ni (3-

d6) was prepared from the deuterium-labelled ligand [AQpiv-d3]H (1a-d3). For an attractive

agostic complex, there should be a preference for the protons to occupy the agostic

positions, which should give a chemical shift change compared to 3.65-66 The 1H NMR

chemical shifts of 3 and 3-d6 are indistinguishable, which unambiguously shows that the

short H-Ni distances in 3 are non-attractive anagostic interactions.

Scheme 3. Synthesis of 3-d6, used in probing potential agostic interactions in 3.

Carboxylate Complexes. Carboxylic acids are a commonly employed additive in 8-AQ

directed Ni-catalyzed C(sp3)—H functionalization. The carboxylate has been proposed to

play an important role in C—H activation and subsequent proton transfer. Paramagnetic

complexes of the type [AQpiv]Ni(O2CtBu) have been proposed as an intermediate and

resting state in the catalytic cycle, but never isolated.55 The reaction of carboxylic acids

with 3 was envisioned as a synthetic route to these speculative paramagnetic Ni(II)

precursors to C—H activation.

The reaction between 3 and 1 equivalent of tBuCO2H in toluene or THF at room

temperature caused an immediate loss of the dark brown colour of 3 in solution and the

formation of {[AQpiv]Ni(O2CtBu)}2 (5) as a green microcrystalline precipitate, as shown

in Scheme 4. Protonolysis of the second [AQpiv] ligand by addition of a second equivalent

9

of tBuCO2H in the presence of PPh3 generates the paddlewheel complex (6-PPh3), shown

on the right side of Scheme 4.

Scheme 4. Synthetic routes to 5, the paramagnetic and dinuclear form of the previously

proposed mononuclear species [AQpiv]Ni(O2CtBu).

Complex 5 proved insoluble in common polar organic solvents such as THF or CH2Cl2.

Crystals of 5 suitable for X-ray diffraction were grown from slow diffusion of layered

toluene solutions of 3 and 6 which undergo slow ligand exchange to generate 5, as shown

on the bottom right of Scheme 4. This reaction also proceeds with [(Et3N)Ni(O2CtBu)2]2

in lieu of 6. An ORTEP depiction of the solid-state molecular structure of 5 is shown in

Figure 2. Complex 5 could also be obtained salt metathesis between 6 with [AQpiv]Na,

but the reaction of 6 with [AQpiv]H without an added base yielded no observable reaction.

10

Figure 2. ORTEP depiction of the solid state molecular structure of 5 (CCDC 2055455)

with 30% thermal ellipsoids. Hydrogens are omitted for clarity. Selected bond lengths (Å):

Ni(1) –N(1) 2.134(4), Ni(1) –N(1)′ 2.174(6), Ni(1) –N(2) 2.030(7), Ni(1) –Ni(1)′ 3.014(2),

Ni(1) –O(1) 2.069(4), Ni(1) –O(2) 2.083(4), Ni(1) –O(3) 2.080(4). Selected bond angles

(deg): Ni(1) –N(1) – Ni(1)′ 88.8(2), O(1) –Ni(1) – O(2) 155.8(2), N(1) –Ni(1) – N(1)′

91.2(2), O(2) –Ni(1) – O(3) 63.3(2), N(1) –Ni(1) – N(2) 81.2(2).

Previously structurally characterized examples containing derivatives of 8-

aminoquinoline are monometallic species.67 Contrary to previously published mechanistic

DFT calculations that predicted 5 should be a mononuclear square planar complex, 5

exhibits a dimeric structure with each nickel center adopting a distorted octahedral

geometry. The structure of 5 has crystallographically imposed inversion symmetry. The

amido nitrogens N(1) and N(1)′ bridge the two Ni centres. The carbonyl groups bend

perpendicular from the plane of the 8-aminoquinoline moieties, allowing the O(1)′ oxygen

atom to chelate to a different nickel than the N(2). This represents the first isolated example

of the proposed catalytically relevant nickel carboxylate intermediate prior to C—H

activation. Dinuclear nickel species have been known to mediate the activation of a number

of C–atom (O, H, X) bonds,68-69 and the possibility of 5 participating in the catalytic cycle

cannot be ruled out, despite its poor solubility. It has been previously reported that the

reaction of [(Et3P)Ni(OPiv)2]2 with an 8-aminoquinoline urea derivative provided a

paramagnetic intermediate that underwent C—H bond activation, though its identity was

not ascertained.55

11

Insolubility rendered the determination of solution NMR data for 5 impossible.

Green complex 5 reacts over an hour in the donor solvents DMSO, and DMF to give brown

solutions. In both solvents, this provides a complex tentatively assigned by NMR as

[AQpiv]Ni(O2CtBu)L (mono-5·L), the mononuclear solvated form of 5, which is in

equilibrium with complex 3 and the paddlewheel complex 6·L (L=DMSO, DMF), as

shown in Scheme 5. Complex 3 was assigned by 1H NMR by comparison to a sample of

isolated 3 dissolved in DMSO, and complex 6·DMSO was assigned by comparison to a

DMSO solution of paddlewheel complex [Ni(O2CtBu)2NEt3]2 , which appeared to generate.

[Ni(O2CtBu)2(DMSO)]2. It should be restated that in the absence of DMF or DMSO, the

reaction of 6·PPh3 and 3 can be used to generate dinuclear 5, suggesting the presence of

the donor solvents influences this equilibrium. The only remaining 1H NMR resonances

for the equilibrium solution that were not assignable to 3 or 6·PPh3 were assignable to

mono-5·DMSO. Complex mono-5·DMSO features broad paramagnetic shifted

resonances, similar to 3, but with an added tBu resonance for the O2CtBu moiety at 8.2

that integrates to 9 H, and has the same integral as the tBu resonance for AQpiv in mono-

5·DMSO at 72.7.

12

Scheme 5. Reaction of dinuclear 5 with donor solvents to give an equilibrium

mixture of the paramagnetic species mono-5·L, 3 and 6, where L =DMSO, DMF.

The NMR assignment of mono-5·L is tentative because it proved impossible to

assign resonances for the coordinated solvent. In principle, this species could be

mononuclear with multiple coordinated solvent molecules rather than one, or could be a

dinuclear solvated species. In order to probe the likely identity of mono-5·L and the

energetics of the equilibria exhibited by 5 in donor solvents, DFT calculations were

performed. Both mononuclear and dinuclear forms of 5 were optimized with one or two

O-bonded DMSO or DMF coordinated to the nickel centers, and are summarized in

Scheme 6. The binding of a single DMSO molecule to dinuclear 5 gives di-5·DMSO and

is calculated to be 11.0 kcal·mol–1 uphill, where the energy given is a G° for the

transformation in the gas phase. The binding of two solvent molecules to 5 gives di-

5·2DMSO, which has a Gibbs free energy change of +9.8 kcal·mol–1; neither dinuclear

species appears viable as the species observed in solution due to these strongly disfavored

reaction thermodynamics, shown in Scheme 6a.

Mononuclear forms proved more favourable, as shown in Scheme 6b. The

dissociation of dinuclear 5 into its mononuclear form [AQpiv]Ni(O2CtBu) (mono-5)

without coordination of a solvent had a favourable G° of –0.3 kcal·mol–1. Although this

seems to suggest mono-5 should be observable, it should be noted that DFT calculations

overestimate the entropic component for solution phase reactions, and dinuclear 5 is

insoluble in most solvents. The reaction of 5 with DMSO to generate the monosolvated

species mono-5·DMSO has a more favourable G° of –3.0 kcal·mol–1 for its most stable

isomer. Coordination of a second DMSO to give mono-5·2DMSO was strongly

disfavoured, with the most stable isomer having a G° of +11.4 kcal·mol–1. These

calculations support the assignment of the solution species observed by 1H NMR as

AQpiv]Ni(O2CtBu)DMSO, mono-5·DMSO.

13

Calculations also showed that the equilibrium between mono-5·DMSO with 3 and

6·2DMSO observed in solution was viable. The calculated G° for this reaction was only

0.1 kcal·mol–1, as shown in Scheme 6c.

Scheme 6. Calculated Gibbs free energies and enthalpies for solvation of 5 with DMSO to

give a) dinuclear complexes and b) mononuclear complexes. Only the formation of mono-

5·DMSO is favourable. c) The calculated energetics of the experimentally observed

equilibrium between mono-5·DMSO and 3 and 6·2DMSO in DMSO.

14

The dissolution of complex 5 in DMF was also investigated computationally. The

conclusion of the study with DMF proved identical to that with DMSO. The paramagnetic

mononuclear monosolvated complex mono-5·DMF is predicted to be the favoured form

in solution, and exist in equilibrium with 3 and 6·2DMF. The energies for these related

complexes are provided in the Supporting Information.

C—H Activation

Both [AQpiv]2Ni (3) and {[AQpiv]Ni(O2CtBu)}2 (5) undergo C—H activation when

heated at 80 °C in benzene-d6, even though 5 is insoluble. The C—H activated products

7·PR3 (where PR3 = PPh3, PiBu3) could be isolated through the addition of an auxiliary

ligand such as phosphines, as shown in Scheme 7. Multinuclear NMR spectroscopy

showed that other coordinating solvents such as MeCN or DMSO also gave adducts

tentatively assigned as 7·NCMe and 7·DMSO, but these could not be isolated as

crystalline solids. Diamagnetic Pd analogues are known.70-75 As shown in Scheme 7a), the

C—H activation of 3 liberates an equivalent of [AQpiv]H (1a), which was observed by 1H

NMR spectroscopy. The C—H activation 5 in the absence of added base also produced

1a, presumably because the tBuCO2H produced by deprotonation of the C—H bond

protonates unreacted 5, generating [AQpiv]H (1a), which lowers the yield. The addition of

Na2CO3 in the C—H activation of 5 was an effective way to suppress this side reaction, as

shown in Scheme 7 b).

15

Scheme 7. a) synthesis of C—H activated adducts 7·PR3 from complex 3 or b) from

complex 5. c) Alternate salt metathesis route to 7·PR3 with room temperature loss of

benzene in the C—H activation step.

The formation of 7·PR3 using 5 as precursor is an order of magnitude faster than 3

at 80 °C. Initial rates of reaction for the conversion of 3 to 7·PPh3 in benzene-d6 were

examined over a range of 30 °C and an Eyring plot provided a ΔG‡ of 23.1 kcal·mol–1. A

computational study by Lan utilizing bicarbonate anion as proton acceptor determined a

barrier of 23.7 kcal·mol–1,76 whereas in Liu’s study, an anionic, DMF-coordinated sodium

carbonate ligand drops the calculated barrier to 21.4 kcal·mol–1.54 The more rapid

activation by 5 vs 3 supports that carboxylate lowers the C—H activation barrier; a similar

effect of carboxylates on the rate of C—H activation are also reported in other transition

metal-catalyzed systems.50, 77-79 Multiple computational studies have pointed out that the

C—H bond is further polarized by the carboxylate through non-covalent interactions in Pd-

catalyzed systems.80 However, as the solid structure has shown, the distance between the

CH3 groups and the carboxylate oxygen in 5 is much longer than a typical hydrogen bond

length, suggesting rearrangement of the tBu group or carboxylate ligand may occur prior

16

to C—H activation; it is unclear at which Ni site the tBu is activated relative to the

coordinated carboxylate ligands, given breaking the [AQpiv] oxyen-nickel interaction in 5

could allow activation at either metal site in this dinuclear complex. Unfortunately the

instability and insolubility of 5 prevented us to study the detailed mechanism of C—H

activation in solution.

Figure 3. ORTEP depictions of 7·PPh3 (CCDC 2055449) and 7·PiBu3 (CCDC

2055446), with 30% thermal ellipsoids.

Adducts 7·PR3 were also conveniently synthesized at room temperature from

reaction between [AQpiv]Na (2a) and trans-NiCl(Ph)(PR3)2 (R=Ph, iBu), as shown in

Scheme 7c). This reaction combines transmetallation and C—H activation, which is this

case with the Ni-Ph group acting as the base promotes very rapid C—H activation at room

temperature. Single crystals of 7·PPh3 and 7·PiBu3 were grown from a saturated THF and

toluene solutions, respectively. The solid state structures indicate they are square planar

and exhibit characteristic Ni—C bonds (1.929(3) Å for 7·PPh3, and 1.935(3) Å for

7·PiBu3), similar to known complexes.55-56, 81-83 The different steric profiles of phosphine

ligands does not have a significant influence on the bond angles, with a N(2)—Ni(1)—

C(1) angle of 168.5(1)° for 7·PPh3 and 166.9(1)° for 7·PiBu3].

Ni(1)C(1)

C(2)

N(2)

N(1)

P(1)

O(1)

Ni(1)

N(1)

N(2)C(1)

P(1)

17

Complexes 7·PR3 are all diamagnetic and feature characteristic coupling of NiCH2

to phosphorus in the 1H NMR spectra of complexes 7·PPh3 (3JHP = 10.5 Hz) and 7·PiBu3

(3JHP = 6.5 Hz), consistent with coordination of the PR3 in solution. The 31P{1H} NMR

also features sharp singlets for 7·PPh3 at δ 42.2, and 7·PiBu3 at δ 5.2; these are observed

downfield compared to the free PR3 by approximately 50 ppm. The addition of free PPh3

to 7·PPh3 converts the 1H NMR CH2 doublet to a singlet, and the phosphorus peak

broadens in the 31P{1H} NMR, consistent with rapid phosphine ligand exchange. In

contrast, the addition of excess PiBu3 to 7·PiBu3 did not cause any evidence of fluxional

exchange, even upon heating to 373 K in toluene-d8.

C—H Functionalization

After C—H activation, the next step in the catalytic cycle is reaction of 7· PR3 with

aryl halides. In an attempt to observe intermediates, the pseudo-catalytic condition

reaction between 7·PiBu3 and iodobenzene in the presence of 1a in benzene-d6 at 80 °C

was monitored by NMR spectroscopy, as shown in Scheme 8a. No Ni(IV) complex from

oxidative addition was observed; if involved, the Ni(IV) complex is likely a high energy

intermediate. In addition to the formation of the organic arylated product 1b, the distinctive

paramagnetic peaks of complex 3 were observable early in the reaction. As increased

conversion of 1a to 1b occurred, new peaks were observed for the complexes 8 and 9, as

shown in Scheme 8. Complexes 8 and 9 are analogues of 3 with arylated ligands, and

feature many 1H NMR chemical environments proximal to those for 3. Complexes 3, 8,

and 9 likely arise from ligand redistribution from putative intermediate 4b shown central

in Scheme 8b, similar to the chemistry of the unobserved complex 4 shown in Scheme 2.

In the 31P{1H} NMR, the broad singlet at 5.0 for NiI2(PiBu3)2 was also observed.

Complexes 3, 8, and 9 are in equilibrium under the reaction conditions, with the relative

proportion of each determined by the ratio of 1a and 1b in solution.

18

Ni(1)

N(1)

N(2)

N(3)

N(4)

Scheme 8. a) Reaction of 7·PiBu3. with PhI in presence of 1a, to give 3, 8 (CCDC

2055459), and 9.

To confirm the identity of species 8 and 9, initially assigned by 1H NMR and

analysis of equilibria, complex 8 was synthesized from NiCl2(PiBu3)2 and ligand 1b, as

shown in Scheme 8c. The solid-state X-ray structure of 8 shows it is structurally similar to

3, with a disphenoidal geometry at Ni. The 1H NMR of 8 exhibits characteristic broad

19

singlets for a paramagnetic Ni(II) species. Although the asymmetric complex 9 could not

be isolated in a pure form, it could be prepared in equilibrium by the addition of 1a to 8,

which demonstrates the validity of the equilibrium shown in Scheme 10b. Alternatively, a

solution of 9 could be prepared by the equilibrium reaction of equimolar amounts of 3 and

8 via ligand redistribution. At 298 K this reaction proceeds over the course of hours.

To support the proposed Ni(II) to Ni(IV) oxidative addition mechanism for the

functionalization step, the influence of aryl iodide on reaction rate was studied, as shown

in Scheme 9a. Initial rate studies were performed for these reactions of 7·PiBu3 with aryl

iodides to generate 1-R. The reaction was done in the presence of excess 1a to avoid the

formation of diarylated products. In the initial stage (< 30 min) of the reaction the rate can

be conveniently determined from the formation of 1b. The reaction was found to be first

order with respect to both 7·PiBu3 and iodobenzene, but inverse first-order for PiBu3. The

inhibition by PiBu3 suggests a mechanism where a pre-equilibrium phosphine dissociation

occurs prior to reaction with aryl iodide. Iodobenzene was used in excess to give pseudo-

first order kinetics, and PiBu3 was added to ensure a constant concentration for all reactions

studied.

20

Scheme 9. a) Reaction conditions for pseudo-first order kinetics study of 7·PiBu3 with

para-substituted aryl iodides to give 1-R. b) Hammett plot comparing initial rates of

arylation.

The electronic effect of para-substituents on the reaction rate was examined using

iodoarenes bearing functional groups at the para-position. A Hammett-plot was

constructed, and a linear correlation with a ρ of –0.74 was observed for iodoarenes bearing

p-NMe2, p-OMe, p-H, and p-CF3 substituents, as shown in Scheme 9b. In contrast to the

positive ρ values often observed for oxidative addition to Ni(0) or Pd(0),84-85the negative ρ

could be appropriate for oxidative addition to a Ni(II) centre. It is reasonable to think the

more electrophilic Ni(II) will react faster with electron-rich arenes; however, Hammett

studies of reactions involving concerted oxidative addition to Ni(II) are currently lacking

for comparison. The small negative value of ρ rules out a rate-determining electron transfer

, because ρ values for this mechanism would be expected to be near 2.0.84 Addition of a

radical scavenger such as TEMPO gave no decrease in the rate of formation of 1b, which

also suggests a radical pathway is unlikely. These experimental results support the results

of computational studies by Liu,54 and Sunoj.53

The p-CO2Et substituted arene is an obvious outlier in Scheme 9b, with a much

faster rate of reaction than anticipated from the Hammett ρ value. To further understand

this exception and whether a concerted mechanism is still operational with this substituent,

DFT studies were performed using Gaussian 16 to analyze both phosphine dissociation and

p-NMe2

p-OMe

H

p-CF3

p-COOEt

ρ = -0.74

-0.5

-0.3

-0.1

0.1

0.3

0.5

0.7

-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6lo

g(k X

/kH)

σp constant

21

oxidative addition steps with respect to 7·PiBu3 that generates the Ni(IV) intermediate

INT-2 through transition state TS-1 (Scheme 10a)). The reaction with 4-iodo-N,N-

dimethylaniline (p-NMe2) is calculated to have the lowest activation energy barrier with a

ΔG‡OA that is 0.6 kcal/mol lower than iodobenzene at 298K. Calculation also revealed the

reaction with ethyl 4-iodobenzoate also has a lower ΔG‡OA than iodobenzene (ΔΔG‡

OA= -

0.1 kcal mol-1) and is slightly higher than 4-iodoanisole (ΔΔG‡OA= 0.1 kcal mol-1), which

is in agreement with our experimental result and a higher rate of reaction is expected. A

plot of calculated ΔG‡OA against the ln of the observed rate of each reaction was also

constructed and a linear correlation was observed, suggesting the same mechanism was

operative throughout the reactions with a series of substituted iodoarenes (Scheme 10b)).

22

Scheme 10. a) DFT computed pathway of the oxidative addition reaction between

iodoarenes and 7·PiBu3 (details are in SI). b) Graph showing correlation between the

observed rate and calculated ΔG‡OA

Catalyst Resting State and the Deleterious Effect of Na2CO3. Intuitively, one might

anticipate either the C-H activation step or the oxidative addition to give Ni(IV) would be

rate-limiting in the Ni-catalyzed C-H functionalization of 1a; however, we have shown

both these steps proceed at temperatures as low as 80 °C under stoichiometric conditions.

In contrast, under catalytic conditions much higher temperatures of 140-160 °C are

required. We examined solutions during catalysis by 1H NMR to try to observe the resting

state of the catalyst and better understand why such high temperatures were required for

catalysis.

The initial attempt to observe a catalyst resting state used 20% Ni(OTf)2 and PPh3

to catalyze the reaction of 1a with PhI and Na2CO3 as the base. Catalysis occurs at

temperatures from 140-160 °C, but very careful attempts to observe a catalyst resting state

by either 1H, 31P{1H} and 19F{1H} NMR failed to detect relevant species. The 1H NMR

featured no peaks associated with Ni species, either diamagnetic or paramagnetic. Every

peak in the 1H spectrum could be assigned to either diamagnetic reagents and products that

did not contain Ni. Similarly, the 31P{1H} NMR only showed PPh3 and the 19F NMR only

showed free triflate anion at –78.2.

A similar experiment was done using 6·PPh3 in lieu of Ni(OTf)2 as the catalyst

precursor. As the solution was heated up to 140-160 °C the 1H NMR signal for 6 in dioxane

p-NMe2

p-OMeH

p-CO2Et p-CF3

-8

-7

-6

-5

-4

-3

-2

23.6 23.8 24 24.2 24.4 24.6 24.8

ln k

Calculated barrier ΔG‡OA

23

disappeared, with no new resonances appearing to replace over the range of –250 to +250

ppm. To test if the catalyst resting state was insoluble, a portion of the reaction mixture

was filtered through Celite. After continuing to heat at 140-160 °C the rate of catalysis of

the filtered and unfiltered samples showed no difference, consistent with a soluble resting

state of the catalyst. To confirm the unobservable resting state is caused by reaction with

Na2CO3, a control experiment was performed heating 6·PPh3, DMSO in dioxane with and

without added Na2CO3. The 1H NMR of the solution of 6·PPh3 heated with Na2CO3 shows

no peaks associated with any Ni species. A hypothesis for the lack of observable resting

state in these reaction was that the Ni(II) precursors were reacting with Na2CO3 to give

dioxane soluble Ni carbonate species. Such a complex would be 1H, 31P and 19F NMR

silent. This result suggests that not only does Na2CO3 fail to effectively deprotonate 1a,

the carbonate anion also binds to Ni(II) to generate a lower energy species, thus increasing

the temperature necessary for catalysis. Previously published DFT studies suggested that

the carbonate bound to Ni(II) along with the 8-AQpiv ligand was the resting state for

catalysis. We found no experimental evidence for 8-AQpiv binding in the resting state.

Alternatives for Na2CO3. With the hypothesis that Na2CO3 was deleterious to catalysis,

NaOtBu was investigated as an alternative base. It is relatively cost effective for synthetic

applications, and with a pKa of 17-18,86 it is a stronger base than Na2CO3 which has a pKa

of ca. 10.5.87 NaOtBu is suitable for the deprotonation of 1a, which is anticipated to have

a pKa around 10. The reaction of NaOtBu with 1a and (Ph3P)2NiI2 in dioxane immediately

generated the distinct paramagnetic 1H NMR signals for 3 at room temperature. This is in

contrast to the same reaction attempted with Na2CO3 in lieu of NaOtBu as the base, where

no reaction is observed even with heating.

The use of NaOtBu as the base under catalytic conditions improved catalyst performance,

and allowed significantly higher catalyst turnover under milder conditions. The reaction

requires an excess of NaOtBu. One equivalent deprotonates the 8-aminoquinoline NH, and

any tBuOH produced appears to sequester an additional equivalent of NaOtBu in the

reaction. Catalysis was observed as low at 100 °C, rather than 140-160 °C as was required

with Na2CO3. However, catalysis still proceeds cleanly at higher temperatures, and using

10 equivalents of NaOtBu allowed a 94% conversion to the trifunctionalized product 1d

after workup, as shown in Scheme 11. The reaction crude showed only 6% remaining

24

difunctionalized product 1c, and no detectable 1b or 1a by NMR. This is a net

functionalization of 98% of the available Me groups in the sample. Neither carboxylic

acids, such as pivalic acid, nor phosphine additives were necessary for catalysis under these

conditions. The increase in reactivity compared to systems that utilize Na2CO3 is dramatic.

The most closely related reactions using Na2CO3 noted in the literature involve more

activated substrates and a net functionalization of only 69% of the available Me groups in

the sample.16

Scheme 11. Catalytic arylation of terminal C(sp3)-H bonds using NaOtBu as the base.

Yields are determined by relative integration in the 1H NMR.

Conclusion

Previous experimental studies related to the Ni catalyzed arylation of C(sp3)—H bonds in

N-(quinolin-8-yl)pivalamide (1a) have largely focused on the mechanistic steps that were

believed to be rate determining, namely the C—H activation and subsequent oxidative

addition to Ni(II). Likewise, previous computational studies also suggested these steps and

the rate determining steps in catalysis. All the former proposed mechanisms are closely

related to those suggested for heavier metals, thus the focus on diamagnetic mononuclear

intermediates. These works left a few key questions remaining regarding the actual

experimental mechanism. The calculated reaction barriers were smaller than would be

expected for a reaction that reaction requires heating to 140-160 °C, and no experimental

resting state had ever been reported for these reactions. Our experimental results show that

25

the intermediates prior to C—H activation and after functionalization are all paramagnetic

Ni(II) species, such as 3, 5, 8 and 9. Both the C—H activation and oxidative addition steps,

previously proposed as likely rate determining steps, occur stoichiometrically at 80 °C,

much lower than the temperatures required for catalysis. Under the original catalytic

conditions employing Na2CO3 as a base, the deprotonation and binding of 1a appears to be

rate-limiting, due to the insufficient basicity of Na2CO3 and its propensity to react with

catalytic precursors like 6 to yield less reactive NMR silent off-cycle resting state. From

these mechanistic insights, a simple approach to improved catalysis in these systems was

developed using readily available NaOtBu as the base. A summary of the observed

mechanistic manifolds is shown in Scheme 12. Catalysis is much more effective with

NaOtBu, and additional additives such as PPh3 or pivalic acid proved unnecessary and yield

no improvement to catalysis. The intermediates outside the red box are only relevant to

catalysis done in the presence of pivalic acid. Further studies are needed to probe the

expanded scope of C—H activation reactions afforded by alternative bases like NaOtBu,

as well as to determine possible alternative mechanisms derived from reaction of Ni species

with this species acting in roles other than simply bases. These studies are currently

underway. The use of Na2CO3 as a base is so ubiquitous in Ni catalyzed reactions that it

raises the question if it is hindering catalysis in a vast number of unrelated systems.

26

Scheme 12. Interconversion of experimental observed intermediates in Ni(II)-mediated C(sp3)-

H arylation.

Corresponding Authors

*E-mail: sjohnson@uwindsor.ca. Fax: +1 519 973 7098. Tel.: +1 519 253 3000 (S.A.J.).

ORCID

Samuel A. Johnson: 0000-0001-6856-0416

Notes

The authors declare no competing financial interest.

Acknowledgements

S.A.J. acknowledges the Natural Sciences and Engineering Research Council (NSERC) of

Canada for funding and SHARCNET and Compute Canada for computational resources.

27

References

1. Daugulis, O.; Roane, J.; Tran, L. D., Bidentate, Monoanionic Auxiliary-Directed Functionalization of Carbon–Hyrogen Bonds. Acc. Chem. Res 2015, 48, 1053-1064. 2. Yan, J.-X.; Li, H.; Xiang-Wei, L.; Shi, J.-L.; Wang, X.; Shi, Z.-J., Palladium-Catalyzed C(sp3)-H Activation: A Facile Method for theSynthesis of 3,4-Dihydroquinolinone Derivatives. Angew. Chem. Int. Ed. 2014, 53, 4945-4949. 3. Shang, R.; Ilies, L.; Matsumoto, A.; Nakamura, E., β-Arylation of Carboxamides via Iron-Catalyzed C(sp3)−H Bond Activation. J. Am. Chem. Soc. 2013, 135, 6030-6032. 4. Daugulis, O.; Do, H.-Q.; Shabashov, D., Palladium- and Copper-Catalyzed Arylation of Carbon−Hydrogen Bonds. Acc. Chem. Res 2009, 42, 1074-1086. 5. Waltz, K. M.; Hartwig, J. F., Selective Functionalization of Alkanes by Transition-Metal Boryl Complexes. Science 1997, 211-213. 6. Arndtsen, B. A.; Bergman, R. G.; Mobley, T. A.; Peterson, H. H., Selective Intermolecular Carbon—Hydrogen Bond Activation by Synthetic Metal Complexes in Homogeneous Solution. Acc. Chem. Res 1995, 28, 154-162. 7. Chirik, P.; Morris, R., Getting Down to Earth: The Renaissance of Catalysis with Abundant Metals. Acc. Chem. Res 2015, 48, 2495-2495. 8. Smith, M. B.; March, J., Advanced Organic Chemistry. 6th Edition ed.; Wiley: New Jersey, 2007. 9. Tobisu, M.; Chatani, N., Remote Control by Steric Effects. Science 2014, 343, 850-851. 10. Shaw, M. H.; Shurtleff, V. W.; Terrett, J. A.; Cuthbertson, J. D.; MacMillan, D. W. C., Native functionality in triple catalytic cross-coupling: sp3 C–H bonds as latent nucleophiles. Science 2016, 352, 1304-1308. 11. Kleiman, J. P.; Dubeck, M., The Preparation of Cyclopentadienyl [o-(Phenylazo)Phenyl]Nickel. J. Am. Chem. Soc. 1963, 85, 1544-1545. 12. Murai, S.; Kakiuchi, F.; Sekine, S.; Tanaka, T.; Kamatani, A.; Sonoda, M.; Chatani, N., Efficient catalytic addition of aromatic carbon-hyrogen bonds to olefins. Nature 1993, 366, 529-531. 13. Daugulis, O.; Roane, J.; Tran, L. D., Bidentate, Monoanionic Auxiliary-Directed Functionalization of Carbon− Hydrogen Bonds. Acc. Chem. Res 2015, 48, 1053-1064. 14. Shiota, H.; Ano, Y.; Aihara, Y.; Fukumoto, Y.; Chatani, N., Nickel-Catalyzed Chelation-Assisted Transformations Involving Ortho C-H Bond Activation: Regioselective Oxidative Cycloaddition of Aromatic Amides to Alkynes. J. Am. Chem. Soc. 2011, 133, 14952-14955. 15. Castro, L. C. M.; Chatani, N., Nickel Catalysts/N,N'-Bidentate Directing Groups: An Excellent Partnership inDirected CH Activation Reactions. Chem. Lett. 2015, 44, 410-421. 16. Aihara, Y.; Chatani, N., Nickel-Catalyzed Direct Arylation of C(sp3)-H Bonds in Aliphatic Amides via Bidentate-Chelation Assistance. J. Am. Chem. Soc. 2014, 136, 898-901. 17. Li, M.; Dong, J.; Huang, X.; Li, K.; Wu, Q.; Song, F.; You, J., Nickel-catalyzed chelation-assisted direct arylation of unactivated C(sp3)–H bonds with aryl halides. Chem. Comm 2014, 50, 3944. 18. Aihara, Y.; Tobisu, M.; Fukumoto, Y.; Chatani, N., Ni(II)-Catalyzed Oxidative Coupling between C(sp2)−H in Benzamides and C(sp3)−H in Toluene Derivatives. J. Am. Chem. Soc. 2014, 136, 15509-15512.

28

19. Aihara, Y.; Wuelbern, J.; Chatani, N., The Nickel(II)-Catalyzed Direct Benzylation, Allylation, Alkylation, and Methylation of CH Bonds in AromaticAmides Containing an 8-Aminoquinoline Moiety as the Directing Group. Bull. Chem. Soc. Jpn. 2015, 88, 438-446. 20. Wu, X.; Zhao, Y.; Ge, H., Nickel-Catalyzed Site-Selective Alkylation of Unactivated C(sp3)-H Bonds. J. Am. Chem. Soc. 2014, 136, 1789-1792. 21. Wu, X.; Zhao, Y.; Ge, H., Direct Aerobic Carbonylation of C(sp2)−H and C(sp3)-H Bonds through Ni/Cu Synergistic Catalysis with DMF as the Carbonyl Source. J. Am. Chem. Soc. 2015, 137, 4924-4927. 22. Liu, Y.-J.; Zhang, Z.-Z.; Yan, S.-Y.; Liu, Y.-H.; Shi, B.-F., Ni(II)/BINOL-catalyzed alkenylation of unactivated C(sp3)–H bonds. Chem. Comm 2015, 51, 7899. 23. Maity, S.; Agasti, S.; Earsad, A. M.; Hazra, A.; Maiti, D., Nickel-Catalyzed Insertion of Alkynes and Electron-Deficient Olefins into Unactivated sp3 C-H Bonds. Chem. Eur. J 2015, 21, 11320-11324. 24. Li, M.; Yang, Y.; Zhou, D.; Wan, D.; You, J., Nickel-Catalyzed Addition-Type Alkenylation of Unactivated, Aliphatic C−H Bonds with Alkynes: A Concise Route to Polysubstituted γ‑Butyrolactones. Org. Lett. 2015, 17, 2546-2549. 25. Castro, L. C. M.; Obata, A.; Aihara, Y.; Chatani, N., Chelation-Assisted Nickel-Catalyzed OxidativeAnnulation via Double C-H Activation/Alkyne Insertion Reaction. Chem. Eur. J 2016, 22, 1362-1367. 26. Cheng, Y.; Wu, Y.; Tan, G.; You, J., Nickel Catalysis Enables Oxidative C(sp2)–H/C(sp2)–H

Cross‐Coupling Reactions between Two Heteroarenes. Angew. Chem. Int. Ed. 2016, 55, 12275-12279. 27. He, Z.; Huang, Y., Diverting C-H Annulation Pathways: Nickel-Catalyzed Dehydrogenative Homologation of Aromatic Amides. ACS Catal. 2016, 6, 7814-7823. 28. Uemura, T.; Yamaguchi, M.; Chatani, N., Phenyltrimethylammonium Salts as Methylation Reagents in the Nickel-Catalyzed Methylation of C-H Bonds. Angew. Chem. Int. Ed. 2016, 55, 3162-3165. 29. Honeycutt, A. P.; Hoover, J. M., Nickel-Catalyzed Oxidative Decarboxylative (Hetero)Arylation of Unactivated C−H Bonds: Ni and Ag Synergy. ACS Catal. 2017, 7, 4597-4601. 30. Luo, F.-X.; Cao, Z.-C.; Zhao, H.-W.; Wang, D.; Zhang, Y.-F.; Xu, X.; Shi, Z.-J., Nickel-Catalyzed Oxidative Coupling of Unactivated C(sp3)-H Bonds in Aliphatic Amides with Terminal Alkynes. Organometallics 2017, 36, 18-21. 31. Wang, X.; Xie, P.; Qiu, R.; Zhu, L.; Liu, T.; Li, Y.; Iwasaki, T.; Au, C.-T.; Xu, X.; Xia, Y.; Yin, S.-F.; Kambe, N., Nickel-catalysed direct alkylation of thiophenes via double C(sp3)–H/C(sp2)–H bond cleavage: the importance of KH2PO4. Chem. Comm 2017, 53, 8316. 32. Tan, G.; Zhang, L.; Liao, X.; Shi, Y.; Wu, Y.; Yang, Y.; You, J., Copper- or Nickel-Enabled Oxidative Cross-Coupling of Unreactive C(sp3)-H Bonds with Azole C(sp2)-H Bonds: Rapid Access to β-Azolyl Propanoic Acid Derivatives. Org. Lett. 2017, 19, 4830-4833. 33. Lin, C.; Chen, Z.; Liu, Z.; Zhang, Y., Nickel-Catalyzed Stereoselective Alkenylation of C(sp(3))-H Bonds with Terminal Alkynes. Org Lett 2017, 19, 850-853. 34. Liu, X.; Mao, G.; Qiao, J.; Xu, C.; Liu, H.; Ma, J.; Sun, Z.; Chu, W., Nickel-catalyzed C–H bond trifluoromethylation of 8-aminoquinoline derivatives by acyl-directed functionalization. Org. Chem. Front. 2019, 6, 1189. 35. Skhiri, A.; Chatani, N., Nickel-Catalyzed Reaction of Benzamides with Bicylic Alkenes: Cleavage of C-H and C-N Bonds. Org. Lett. 2019, 21, 1774-1778. 36. Derosa, J.; van der Puyl, V. A.; Tran, V. T.; Liu, M.; Engle, K. M., Directed nickel-catalyzed 1,2-dialkylation of alkenyl carbonyl compounds. Chem. Sci. 2018, 9, 5278.

29

37. Wang, X.; Qiu, R.; Yan, C.; Reddy, V. P.; Zhu, L.; Xu, X.; Yin, S.-F., Nickel-Catalyzed Direct Thiolation of C(sp3)−H Bonds in Aliphatic Amides. Org. Lett. 2015, 17, 1970-1973. 38. Obata, A.; Ano, Y.; Chatani, N., Nickel-catalyzed C–H/N–H annulation of aromatic amides with alkynes in the absence of a specific chelation system. Chem. Sci 2017, 8, 6650. 39. Wu, X.; Zhao, Y.; Ge, H., Nickel-Catalyzed Site-Selective Amidation of Unactivated C(sp3)-H Bonds. Chem. Eur. J 2014, 20, 9530-9533. 40. Ye, X.; Peterson, J. L.; Shi, X., Nickel-catalyzed directed sulfenylation of sp2 and sp3 C–H bonds. Chem. Comm 2015, 51. 41. Lin, C.; Yu, W.; Yao, J.; Wang, B.; Liu, Z.; Zhang, Y., Nickel-Catalyzed Direct Thioetherification of β‑C(sp3)−H Bonds of Aliphatic Amides. Org Lett 2015, 17. 42. Yan, S.-Y.; Liu, Y.-J.; Liu, B.; Liu, Y.-H.; Zhang, Z.-Z.; Shi, B.-F., Nickel-catalyzed direct thiolation of unactivated C(sp3)–H bonds with disulfides. Chem. Comm 2015, 51. 43. Yokota, A.; Chatani, N., Ni(II)-Catalyzed Sulfonylation of ortho CH Bonds in AromaticAmides Utilizing an N,N-Bidentate Directing Group. Chem. Lett. 2015, 44, 902-904. 44. Aihara, Y.; Chatani, N., Nickel-Catalyzed Reaction of C−H Bonds in Amides with I2: ortho- Iodination via the Cleavage of C(sp2)-H Bonds and Oxidative Cyclization to β-Lactams via the Cleavage of C(sp3)−H Bonds. ACS Catal. 2016, 6, 4323-4329. 45. Iwasaki, M.; Miki, N.; Tsuchiya, Y.; Nakajima, K.; Nishihara, Y., Synthesis of Benzoisoselenazolone Derivatives by Nickel-Catalyzed Dehydrogenative Direct Selenation of C(sp2)-H Bonds with Elemental Selenium in Air. Org. Lett. 2017, 19, 1092-1095. 46. van der Puyl, V. A.; Derosa, J.; Engle, K. M., Directed, Nickel-Catalyzed Umpolung 1,2-Carboamination of Alkenyl Carbonyl Compounds. ACS Catal. 2019, 9, 224-229. 47. Xu, S.; Takamatsu, K.; Hirano, K.; Miura, M., Synthesis of Seven-Membered Benzolactones by Nickel-Catalyzed C-H Coupling of Benzamides with Oxetanes. Chem. Eur. J 2019, 25, 1-6. 48. Yu, L.; Chen, X.; Liu, D.; Hu, L.; Yu, Y.; Huang, H.; Tan, Z.; Gui, Q., Direct Synthesis of Primary Anilines via Nickel-mediated C(sp2)- H Aminations. Adv. Synth. Catal. 2018, 360, 1346-1351. 49. Shi, Y.; Li, M.-S.; Zhang, F.; Chen, B., Nickel(II)-catalyzed tandem C(sp2)–H bond activation and annulation of arenes with gem-dibromoalkenes. RSC Adv. 2018, 8, 28668. 50. Gorelsky, S. I.; Lapointe, D.; Fagnou, K., Analysis of the Palladium-Catalyzed (Aromatic)C-H Bond Metalation−Deprotonation Mechanism Spanning the Entire Spectrum of Arenes. J. Org. Chem. 2012, 77. 51. Davies, D. L.; Donald, S. M. A.; Macgregor, S. A., Computational Study of the Mechanism of Cyclometalation by Palladium Acetate. J. Am. Chem. Soc. 2005, 127, 13754-13755. 52. Liu, J.-B.; Tian, Y.-Y.; Zhang, X.; Wang, L.-L.; Chen, D.-Z., A computational mechanistic study of Pd(II)- catalyzed γ-C(sp3)–H olefination/cyclization of amines: the roles of bicarbonate and ligand effect. Dalton Trans. 2018, 47. 53. Singh, S.; K, S.; Sunoj, R. B., Aliphatic C(sp3)-H Bond Activation Using Nickel Catalysis: Mechanistic Insights on Regioselective Arylation. J. Org. Chem. 2017, 82, 9619-9626. 54. Omar, H. M.; Liu, P., Computational Study of Ni-Catalyzed C-H Functionalization: Factors That Control the Competition of Oxidative Addition and Radical Pathways. J. Am. Chem. Soc. 2017, 139, 9909-9920. 55. Beattie, D. D.; Grunwald, A. C.; Perse, T.; Schafer, L. L.; Love, J. A., Understanding Ni(II)-Mediated C(sp3)−H Activation: Tertiary Ureas as Model Substrates. J. Am. Chem. Soc. 2018, 140, , 12602-12610. 56. Hill, E. A.; Zhao, N.; Filatov, A. S.; Anderson, J. S., Nickel(II)-methyl complexes adopting unusual seesaw geometries. Chem. Commum. 2020, 2020, 7861-7864.

30

57. Graziani, R.; Vidali, M.; Casellato, U.; Vigato, P. A., Preparation and crystal structure of a nickel (II)-Uranyl(VI) binuclear chelate. Transiton. Met. Chem. 1978, 3. 58. Li, J.; Tian, D.; Song, H.; Wang, C.; Zhu, X.; Cui, C.; Cheng, J., Synthesis, Structures, and Reactivity of Nickel Complexes Incorporating Sulfonamido-Imine Ligands. Organometallics 2008, 27. 59. Ghannam, J.; Al Assil, T.; Pankratz, T. C.; Lord, R. L.; Zeller, M.; Lee, W. T., A Series of 4- and 5-Coordinate Ni(II) Complexes: Synthesis, Characterization, Spectroscopic, and DFT Studies. Inorg, Chem. 2018, 57, 8307-8316.

60. Zhang, S. K.; Struwe, J.; Hu, L.; Ackermann, L., Nickela‐electrocatalyzed C−H

Alkoxylation with Secondary Alcohols: Oxidation‐Induced Reductive Elimination at Nickel(III). Angew. Chem. Int. Ed. 2019, 59, 3178-3183. 61. He, Z.; Huang, Y., Diverting C–H Annulation Pathways: Nickel-Catalyzed Dehydrogenative Homologation of Aromatic Amides. ACS Catal. 2016, 6, 7814-7823. 62. Maity, S.; Kancherla, R.; Dhawa, U.; Hoque, E.; Pimparkar, S.; Maiti, D., Switch to Allylic Selectivity in Cobalt-Catalyzed Dehydrogenative Heck Reactions with Unbiased Aliphatic Olefins. ACS Catal. 2016, 6, 5493-5499. 63. Chatturgoon, T.; Akerman, M. P., X-ray and DFT-calculated structures of bis[N-(quinolin-8-yl)benzamidato-κ2-N,N']copper(II). Acta Crystallogr.,Sect.C:Cryst.Struct.Chem. 2016, 72, 234. 64. Shilov, A. E.; Shul'pin, G. B., Activation of C-H Bonds by Metal Complexes. Chem. Rev. 1997, 97, 2879-2932. 65. Macaulay, C. M.; Samolia, M.; Ferguson, M. J.; Sydora, O. L.; Ess, D. H.; Stradiotto, M.; Turculet, L., Synthetic investigations of low-coordinate (N-phosphino-amidinate) nickel chemistry: agostic alkyl complexes and benzene insertion into Ni–H. Dalton Trans. 2020, 49, 4811-4816. 66. Brookhart, M.; Green, M. L. H.; Parkin, G., Agostic interactions in transition metal compounds. Proc. Natl. Acad. Sci. U. S. A. 2007, 104, 6908-6914. 67. Roy, P.; Bour, J. R.; Kampf, J. W.; Sanford, M. S., Catalytically Relevant Intermediates in the Ni-Catalyzed C(sp2)–H and C(sp3)–H Functionalization of Aminoquinoline Substrates. J. Am. Chem. Soc. 2019, 141. 68. Ghorai, D.; Finger, L. H.; Zanoni, G.; Ackermann, L., Bimetallic Nickel Complexes for Aniline C-H Alkylations. ACS Catal. 2018, 8, 11657-11662. 69. Somerville, R. J.; Hale, L. V. A.; Gomez-Bengoa, E.; Bures, J.; Martin, R., Intermediacy of Ni-Ni Species in sp2C-O Bond Cleavage of Aryl Esters: Relevance in Catalytic C-Si Bond Formation. J. Am. Chem. Soc. 2018, 140, 8771-8780. 70. Jiang, Y.; Zhang, S.-Q.; Cao, F.; Zou, J.-X.; Yu, J.-L.; Shi, B.-F.; Hong, X.; Wang, Z., Unexpected Stability of CO-Coordinated Palladacycle in Bidentate Auxiliary Directed C(sp3)–H Bond Activation: A Combined Experimental and Computational Study. Organometallics 2019, 38, 2022-2030. 71. Zhang, S.-Y.; Li, Q.; He, G.; Nack, W. A.; Chen, G., Pd-Catalyzed Monoselective ortho-C−H Alkylation of N‑Quinolyl Benzamides: Evidence for Stereoretentive Coupling of Secondary Alkyl Iodides. J. Am. Chem. Soc. 2015, 137, 531-539. 72. Czyz, M. L.; Weragoda, G. K.; Horngren, T. H.; Connell, T. U.; Gomez, D.; O'Hair, R. A. J.; Polyzos, A., Photoexcited Pd(II) auxiliaries enable light-induced control in C(sp3)–H bond functionalisation. Chem. Sci. 2020, 11, 2455. 73. Shabashov, D.; Daugulis, O., Auxiliary-Assisted Palladium-Catalyzed Arylation and Alkylation of sp2 and sp3 Carbon-Hydrogen Bonds. J. Am. Chem. Soc. 2010, 132, 3965-3972.

31

74. Meng, Y.-Y.; Si, X.-J.; Song, Y.-Y.; Zhou, H.-M.; Xu, F., Palladium-catalyzed decarbonylative annulation of phthalimides with arynes: direct construction of phenanthridinones. Chem. Commun. 2019, 55, 9507-9510. 75. Deb, A.; Singh, S.; Seth, K.; Pimparkar, S.; Bhaskararao, B.; Guin, S.; Sunoj, R. B.; Maiti, D., Experimental and Computational Studies on Remote γ-C(sp3)−HSilylation and Germanylation of Aliphatic Carboxamides. ACS Catal. 207, 7, 8171-8175. 76. Zhang, T.; Liu, S.; Zhu, L.; Liu, F.; Zhong, K.; Zhang, Y.; Bai, R.; Lan, Y., Theoretical study of FMO adjusted C-H cleavage and oxidative addition in nickel catalysed C-H arylation. Commun. Chem. 2019, 2. 77. Ackermann, L., Carboxylate-Assisted Transition-Metal-Catalyzed C-H Bond Functionalizations: Mechanism and Scope. Chem. Rev. 2011, 111, 1315-1345. 78. Rousseaus, S.; Gorelsky, S. I.; Chung, B. K. W.; Fagnou, K., Investigation of the Mechanism of C(sp3)-H Bond Cleavage in Pd(0)-Catalyzed Intramolecular Alkane Arylation Adjacent to Amides and Sulfonamides. J. Am. Chem. Soc. 2010, 132, 10692-10705. 79. Balcells, D.; Clot, E.; Eisenstein, O., C—H Bond Activation in Transition Metal Species from a Computational Perspective. Chem. Rev. 2010, 110, 749-823. 80. Boutadla, Y.; Davies, D. L.; Macgregor, S. A.; Poblador-Bahamonde, A. I., Mechanisms of C–H bond activation: rich synergy between computation and experiment. Dalton Trans. 2009, 5820-5831, and references therein. 81. Gutsulyak, D. M.; Piers, W. E.; Borau-Garcia, J.; Parvez, M., Activation of Water, Ammonia, and Other Small Molecules by PCcarbeneP Nickel Pincer Complexes. J. Am. Chem. Soc. 2013, 135, 11776-11779. 82. LaPierre, E. A.; Piers, W. E.; Spasyuk, D. M.; Bi, D. W., Activation of Si–H bonds across the nickel carbene bond in electron rich nickel PCcarbeneP pincer complexes. Chem. Commum. 2016, 52, 1361. 83. Schultz, M.; Eisenträger, F.; Regius, C.; Rominger, F.; Hanno-Igels, P.; Jakob, P.; Gruber, I.; Hofmann, P., Crowded Diphosphinomethane Ligands in Catalysis: [(R2PCH2PR2-κ2P)-NiR']+ Cations for Ethylene Polymerization without Activators. Organometallics 2012, 31, 207-224. 84. Tsou, T. T.; Kochi, J. K., Mechanism of Oxidative Addition. Reaction of Nickel(O) Complexes with Aromatic Halides. J. Am. Chem. Soc. 1979, 101, 6319-6332. 85. Amatore, C.; Pfluger, F., Mechanism of oxidative addition of palladium(0) with aromatic iodides in toluene, monitored at ultramicroelectrodes. Organometallics 1990, 9, 2276-2282. 86. Dewick, P. M., Acids and Bases. In Essentials of Organic Chemistry: For Students of Pharmacy, Medicinal Chemistry and Biological Chemistry, John Wwiley & Sons. Ltd.: 2006; pp 122-166. 87. Windholz, M., In The Merck index an encyclopedia of chemicals, drugs, and biologicals, 10th Ed. ed.; Merck: tahway, N. J, 1983.

download fileview on ChemRxivMechanism_Ni_CH_arylation_SJ.pdf (1.37 MiB)

1

Supporting Information

Mechanism of 8-Aminoquinoline Directed Ni-

Catalyzed C(sp3)-H Functionalization: Paramagnetic

Ni(II) Species, and the Deleterious Effect of Na2CO3

as a Base.

Junyang Liu, and Samuel A. Johnson

Department of Chemistry and Biochemistry, University of Windsor, Sunset Avenue 401,

Windsor, ON, N9B 3P4, Canada

Corresponding author: sjohnson@uwindsor.ca

Experimental

General considerations

Unless otherwise stated, all reactions were carried out in an inert atmosphere under standard

Schlenk or glovebox techniques. Benzene-d6 and toluene-d8 were degassed by three freeze-

pump-thaw cycles, and subsequently dried by running through a column of activated alumina.

Degassed DMSO-d6 was dried by standing over activated alumina for 12 h and stored over

activated 3 Å molecular sieves. Anhydrous Na2CO3 was further dried by heating under vacuum

overnight at 200 °C. NaOtBu was purified by sublimation at 180 °C under vacuum. Anhydrous

solvents and reagents were purchased from Millipore Aldrich (Sigma Aldrich), or Alfa Aesar, or

Oakwood Chemicals. 4-iodo-N,N-dimethylaniline was synthesized using literature procedure.1 1H, 13C{1H}, 19F{1H}, and 31P{1H} NMR spectra were recorded on a Bruker AMX Spectrometer

operating at either 300 MHz or 500 MHz with respect to proton nuclei. Benzene-d6, DMSO-d6,

chloroform-d and toluene-d8 were purchased from Cambridge Isotope Laboratory.

Hexamethyldisiloxane (HMDSO) was used as internal standard for kinetic studies.

Synthesis of N-(quinolin-8-yl)pivalamide (1a). 1a was synthesized using a bi-phasic system,

a modification of a previously reported synthesis that required column chromatography for

purification.2 In a 250 mL round-bottom flask, 8-aminoquinoline (2.88 g, 20 mmol) was dissolved

in 70 mL of diethyl ether layered on top of an aqueous solution (50 mL) of KOH (3.01 g, 53.5

mmol). Trimethylacetyl chloride (2.46 mL, 20 mmol) was added dropwise and the reaction

2

mixture was stirred for 30 min. The two layers were separated using a 250 mL separatory funnel.

The aqueous layer was washed with diethyl ether (30 mL × 2). The combined organic layer was

dried with sodium sulfate and concentrated on a rotary evaporator. A yellow oil was obtained

(3.79 g, 83% yield) and further dried under vacuum at 50 °C for 1 h. NMR spectra in chloroform-

d match previously reported.2 1H NMR (C6D6, 25 °C, 500 MHz ): δ 1.30 (s, 9H, C(CH3)3); 6.77(dd,

1H, 3JHH = 8.3 Hz, 3JHH = 4.2 Hz); 7.05(dd, 1H, 3JHH = 8.3 Hz, 4JHH = 1.1 Hz); 7.25(dd, 1H, 3JHH

= 8.0 Hz); 7.50(dd, 1H, 3JHH = 8.2 Hz, 4JHH = 1.6 Hz); 8.50(dd, 1H, 3JHH = 8.2 Hz, 3JHH = 4.2 Hz);

9.38(dd, 1H, 3JHH = 7.8 Hz, 4JHH = 1.1 Hz); 10.38(s, 1H, NH). 13C{1H} NMR (C6D6, 25 ⁰C, 125

MHz ): δ 27.8 (3C), 40.4 (1C), 116.7 (1C), 121.1 (1C), 121.5 (1C), 128.3 (1C), 135.7 (1C), 136.4

(1C), 139.1 (1C), 148.1 (1C), 176.4 (1C), 180.9 (1C).

Figure S1. 1H NMR of N-(quinolin-8-yl)pivalamide 1a in C6D6.

3

Figure S2. 13C{1H} NMR of N-(quinolin-8-yl)pivalamide 1a in C6D6.

Synthesis of sodium salt of pivaloyl(quinolin-8-yl)amide (2a). A toluene solution of 1a (3.00

g, 13.1 mmol) in 80 mL of toluene was added dropwise to a 250 mL two-neck round bottom

flask equipped with a reflux condenser containing a suspension of NaH (0.314 g, 13.1 mmol) in

40 mL of toluene. The reaction mixture was refluxed overnight. The solvent was removed in

vacuo and the resulting solid was triturated in n-pentane and filtered. The filter cake was washed

with anhydrous n-pentane (10 mL × 2) to remove any residual unreacted 1a to give a near

quantitative yield of yellow powder 2a. 1H NMR (DMSO-d6, 25 °C, 500 MHz ): δ 1.17 (s, 9H,

C(CH3)3); 7.02 (dd, 1H, 3JHH = 7.8 Hz, 4JHH = 1.2 Hz); 7.23 (dd, 1H, 3JHH = 7.8 Hz); 7.28 (dd, 1H, 3JHH = 8.2 Hz, 3JHH = 4.1 Hz); 7.81 (dd, 1H, 3JHH = 7.8 Hz, 4JHH = 1.2 Hz); 8.06 (dd, 1H, 3JHH =

8.2Hz, 4JHH = 1.8 Hz); 8.58 (dd, 1H, 3JHH = 4.0 Hz, 4JHH = 1.8 Hz). 13C{1H} NMR (DMSO-d6, 25

°C, 125 MHz ): δ 29.6 (s, 3C); 38.3 (s, 1C), 114.6 (s, 1C); 119.6(s, 1C); 121.6 (s, 1C); 126.9 (s,

1C); 129.1(s, 1C); 135.8 (s, 1C); 144.2 (s, 1C); 146.3 (s, 1C); 153.6 (s, 1C); 179.2 (s, 1C). Anal.

Calcd. for C14H15N2NaO. C: 67.19, H: 6.04, N: 11.19. Found: C: 66.88, H: 6.04, N: 10.90.

4

Figure S3. 1H NMR of sodium N-(quinolin-8-yl)pivalamide (2a) in DMSO-d6. * indicates residual toluene

in DMSO-d6.

5

Figure S4. 13C{1H} NMR of sodium N-(quinolin-8-yl)pivalamide 2a in DMSO-d6.

Synthesis of bis(pivaloyl(quinolin-8-yl)amido)nickel(II), [AQpiv]2Ni (3). A mixture of 2a (2.00

g, 8.00 mmol), (Ph3P)2NiCl2 (2.614 g, 4.00 mmol) and 80 mL of toluene was added to a 250 mL

round bottom flask equipped with a gas adapter. The reaction mixture was vigorously stirred at

room temperature for 1 h and turned dark brown. The solution was filtered through a pad of

Celite® and the solvent was removed in vacuo. The crude product was triturated with n-pentane

and filtered. Further purification was done by recrystallization from toluene at –40 °C (1.231 g,

60% yield). Crystals of 3 suitable for X-Ray diffraction were grown from slow evaporation of a

benzene solution of 3 layered with hexamethyldisiloxane. 1H NMR (C6D6, 25 °C, 500 MHz ), δ

5.07 (br s, 1H, ); 9.80 (br s, 1H); 12.86 (br s, 1H); 24.85 (br s, 1H); 63.69 (br s, 9H); 68.85 (br s,

1H); 216.19(br s, 1H). 13C{1H} NMR (C6D6, 25 °C, 125 MHz ) δ -55.61(s, 1C); 76.85(s, 1C);

98.20(s, 1C); 107.93(s, 1C); 225.40(s, 1C); 229.64(s, 1C); 394.73(s, 1C); 455.24(s, 1C);

624.73(s, 9C); 852.89 (s, 1C). Two carbon environments could not be located, and are likely

overlapped with the solvent peak or are broad to be observed. Anal. Calcd. for C28H30N4NiO2.

C: 65.52, H: 5.89, N: 10.92. Found: C: 65.39, H: 5.71, N: 10.60.

6

Figure S5. 1H NMR of 3 in C6D6. (* indicate co-crystalized toluene)

Figure S6. 13C{1H} NMR of 3 in C6D6

7

Synthesis of bis(pivaloyl-d3(quinolin-8-yl)amido)nickel(II) (3-d6). 1-d3 was prepared

according to the previously reported procedure with modification.4 Lithium diisopropylamide

(LDA) (1.478 g, 13.8 mmol) was dissolved in 50 mL of THF, hexane (1:5) mixture and cooled

to –78 °C. To this solution, isobutyric acid (0.610 g, 6.90 mmol) was added dropwise over 10

min. The mixture was stirred for 1 h while allowing it to warm to room temperature, and 1H NMR

spectra of aliquots were taken to ensure complete deprotonation. The solution was cooled to –

40 °C, iodomethane-d3 (0.44 mL, 6.90 mmol), diluted in 5 mL of THF, was added dropwise over

10 min. The reaction vessel was wrapped with aluminum foil, and the mixture was stirred

overnight at room temperature. The solution was cooled in an ice bath and quenched with 1M

HCl(aq) until acidic. The product was extracted with diethyl ether (3 × 30 mL) and the organic

layer was dried using Na2SO4 and filtered. The solvent was removed using a rotary evaporator

to afford trimethylacetic acid-d3 (0.529 g, 73 % yield). Trimethylacetic acid-d3 was converted to

trimethylacetyl chloride-d3 by stirring with SOCl2 (2.00 mL, 27.5 mmol) in 50 mL of DCM for 8 h.

The Remaining SOCl2 and DCM were removed by distillation under N2 to afford trimethylacetyl

chloride-d3 (0.492g, 95%), which was used to synthesize 1-d3 using the same method as 1a,

and subsequently converted to 3-d6 using the same method as the synthesis of 3.

Figure S7. 1H NMR of 3-d6 in C6D6. (* indicate co-crystalized toluene)

8

Synthesis of {[AQpiv]Ni(O2CtBu)}2 (5). Solid 3 (400 mg, 0.78 mmol), and 6·PPh3 (407 mg, 0.39

mmol) were mixed in 20 mL toluene overnight at room temperature. A light green precipitate

formed. The mixture was filtered and the precipitate was washed with toluene and n-pentane

and dried under vacuum, which gave 5 in near quantitative yield. Complex 5 isn’t soluble in

common organic solvents, and reacts slowly with DMSO to give an equilibrium between a

species tentatively assigned as {[AQpiv]Ni(O2CtBu)DMSO (5·DMSO) , which over 30 minutes

convert to an equilibrium mixture with 3 and Ni(OPiv)2DMSOn in solution. Crystals of 5 suitable

for X-Ray diffraction were grown from layered toluene solutions of 3, and 5. 1H NMR (DMSO-

d6, 25 °C, 500. MHz) (peaks were assigned by comparing spectra of 3 and 6·PPh3 in DMSO-

d6). 8.22 (s, br, 9H, pivaloyl-H), 13.25 (s, 1H, quinolyl-H), 17.40(s, 1H, quinolyl-H), 22.04(s,

1H, quinolyl-H), 32.81(s, 1H, quinolyl-H), 59.37(s, 1H, quinolyl-H), 72.7(s, br,9H, tBuCOO),

233.2 (s, br, 1H, quinolyl-H). Anal. Calc. (With 1 co-crystalized toluene molecule included)

C45H56N4Ni2O6: C: 62.39 H: 6.52 N: 6.47, Best found: C: 61.73, H: 6.25, N: 6.19. Elemental

analysis gave variable and consistently low C, despite multiple samples analyzed; this is not

uncommon for Ni complexes.

Figure S8. 1H NMR of 5 in DMSO-d6. * indicate toluene. 3 was also observed as 5 reacts with solvent.

3 3 3

9

Synthesis of 6·PPh3. Potassium trimethylacetate (87 mg, 0.62 mmol), NiCl2(PPh3)2 (200 mg,

0.31 mmol) were combined in 10 mL of toluene. A green solution was obtained after stirring

overnight at room temperature. The solution was filtered through a pad of Celite® before

removing the solvent in vacuo. The resulting green solid was washed with n-pentane and dried

under vacuum to give a green microcrystalline powder (198 mg, 62% yield). Crystals suitable

for X-Ray diffraction was grown from slow evaporation of a benzene solution of 6·PPh3 layered

with HMDSO. 1H NMR (C6D6, 25 °C, 500 MHz), δ 4.08 (br s, 6H, p-H), 4.47(br s, 36 H, tBu -

4.60 (br s, 12H, aromatic H), 9.185 (br s, 12H, aromatic H). 13C{1H} NMR (C6D6, 25 °C, 125

MHz), δ 44.3 (s, 1C), 126.2 (s, 1C), 145.4 (s, 1C), 201.8 (s, 1C), 205.7 (s, 1C), 319.9 (s, 1C).

One carbon environment could not be located, likely to be overlapped with solvent peak or peak

is too broad to be observed. The 31P{1H} NMR did not show any signal. Anal. Calcd. for

C56H66Ni2O8P2. C: 64.27, H: 6.36. Found: C: 64.23, H: 6.26. Evan’s Method (C6D6, 298K), μeff

= 2.97 μB.

10

Figure S9. 1H NMR of 6·PPh3 in C6D6

Figure S10. 13C{1H} NMR of 6·PPh3 in C6D6

11

Figure S11. 31P{1H} NMR of 6·PPh3 in C6D6, showing no observable signal in the normal range.

Synthesis of trans-[NiCl(Ph)(PPh3)2]. The synthesis of trans-[NiCl(Ph)(PPh3)2] was carried

out according to literature procedures with modifications.3 NiCl2 (0.500 g, 3.85 mmol), zinc dust

(0.255 g, 3.90 mmol), triphenylphosphine (4.048 g, 15.43 mmol), toluene (85 mL), and DMF (15

mL) were combined in a 250 mL flask equipped with a gas adapter. The mixture was stirred

vigorously and heated in a 55 °C oil bath and turned dark red. The reaction was stirred for an

additional 3 h. The reaction mixture was cooled to room temperature, filtered under N2 and dried

in vacuo. The resulting Ni(PPh3)4 (3.504 g, 82% yield) was used immediately without any further

purification. Chlorobenzene (0.40 mL, 3.60 mmol), was added to a toluene solution of Ni(PPh3)4

(2.00 g, 1.80 mmol) and stirred overnight to obtain a dark yellow solution. The solution was

dried in vacuo to give a yellow solid. The solid was washed with n-pentane (4 × 25 mL) to

remove excess PPh3. The solid was dried to give trans-[NiCl(Ph)(PPh3)2] (1.093 g, 92 % yield) ,

whose NMR spectra matched with reported literature.3

Synthesis of 7·PPh3. A mixture of 2a (0.410 g, 1.63mmol) and trans-[NiCl(Ph)(PPh3)2] (1.20 g,

1.72 mmol) in 20 mL of toluene was stirred at room temperature for 6 h until the solution was

deep orange-red. The resulting mixture was filtered through Celite® and the solvent was

removed in vacuo. The crude was triturated with n-pentane to afford an orange powder. 7·PPh3

12

was further washed with n-pentane (2 × 15 mL) and isolated in 80% yield (0.717 g). Alternatively,

7·PPh3 can be synthesized by refluxing 3 (0.513 g, 1 mmol) and Ph3P (289 mg, 1.1 mmol) in

toluene in a 50 mL flask equipped with a reflux condenser. The reaction mixture was refluxed

overnight to obtain a deep orange solution. The solvent was removed in vacuo and the crude

was washed with n-pentane to remove any excess PPh3 and free 1a. Crystals suitable for X-

Ray diffraction were grown from slow evaporation of a THF solution of 7·PPh3 . 1H NMR (C6D6,

25 °C, 500 MHz ), δ 1.14 (d, 2H, 3JHP=10.5 Hz, CH2), 1.59 (s, 6H, C(CH3)2), 5.98 (dd, 1H, 3JHH

= 8.4 Hz, 5.5 Hz), 6.81 (dd, 1H, 0.9Hz), 6.98 (m, 9H), 7.26 (dd, 1H, 3JHH= 8.3Hz, J = 1.3Hz),

7.36 (dd, 1H, 3JHH= 4.5 Hz, J = 1.2Hz), 7.37 (t, 1H, 3JHH = 8Hz), 7.79 (m, 6H), 10.02 (dd, 1H, 3JHH=8Hz, J= 0.8Hz). 13C{1H} NMR (C6D6, 25 °C, 125 MHz ) δ 30.66 (s, 2C), 31.91 (d, 1C,

J=19Hz), 49.36 (s, 1C), 116.68 (s, 1C), 119.82 (s, 1C), 120.34 (1C), 128.34 (1C), 128.64 (d,

6C, J=10Hz), 129.32 (s, 1C), 130.40 (s, 1C), 130.47 (s, 1C), 132.79(d, 3C, J=40Hz), 135.02 (d,

6C, J=12.5Hz), 137.39 (s, 1C), 146.44 (s, 1C), 148.97 (s, 1C), 149.31 (s, 1C). 31P {1H} NMR

(C6D6, 25 °C, 202 MHz), δ 42.19 (s, 1P). Anal. Calcd. for C32H29N2NiOP. C: 70.23, H: 5.34, N:

5.12. Found: C: 70.41, H: 5.45, N: 4.93.

Figure S12. 1H NMR of 7·PPh3 in C6D6. * indicate co-crystalized toluene.

13

Figure S13. 13C{1H} NMR of 7·PPh3 in C6D6.

14

Figure S14. 31P{1H} NMR of 7·PPh3 in C6D6

Synthesis of 7·PiBu3. Complex 7·PiBu3 was synthesized in the same way as 7·PPh3 but using iBu3P in lieu of Ph3P. Alternatively, to a solution of Ni(COD)2 (3.00 g, 10.9 mmol) in toluene (80

mL), PiBu3 (4.64 g, 22.9 mmol) was added and stirred for 1 h at room temperature. To the deep

red solution, chlorobenzene (3.5 mL, 34.5 mmol) was added dropwise over 30 min at room

temperature and stirred overnight to afford a dark yellow solution. Volatiles were removed in

vacuo and the crude waxy dark yellow solid (iBu3P)2NiCl(Ph) was used without further

purification. The resulting dark yellow crude was dissolved in 50 mL of toluene and 2a (2.73 g,

10.9 mmol) was added and stirred at room temperature overnight to give a dark orange solution.

The mixture was filtered through a pad of Celite® and dried under vacuum; the resulting orange

crude was washed with n-pentane to remove any excess phosphines (2.76 g, 52% yield).

Crystals suitable for X-Ray diffraction were grown from toluene at –40 °C. 1H NMR (C6D6, 25

°C, 500 MHz ) of 7·PiBu3, δ 1.02 (d, 18H, 3JHH = 6.5Hz), 1.18 (d, 2H, 3JHP = 9.1Hz), 1.36 (dd,

6H, 3JHH = 2JHP = 7.0Hz), 1.73 (s, 6H), 1.84 (d of septets, 3H, 3JHH = 7.0 Hz, 6.5Hz), 6.59 (dd,

1H, 3JHH = 8.1Hz, 4.9Hz), 6.82 (d, 1H, 3JHH = 8.1 Hz), 7.33 (dd, 1H, 3JHH = 7.8 Hz) , 7.49 (d, 1H, 3JHH = 7.9Hz), 8.00 (d, 1H, 3JHH = 4.5Hz), 9.94 (d, 1H, 3JHH = 7.8Hz). 13C{1H} NMR (C6D6, 25

°C, 125 MHz ) of 7·PiBu3, δ 25.28 (s, 6C), 25.33 (s, 3C), 25.46 (d, 3C, 1JCP =23Hz), 30.91 (s,

2C), 32.73 (d, 1C, 3JCP =20Hz), 49.11 (d, 1C, 4JCP =2.7Hz), 116.41 (s, 1c), 119.95 (s, 1c), 120.29

(s, 1C), 129.60 (s, 1C), 130.53 (s, 1C), 137.62 (s, 1C), 146.33 (d, 1C, 4JCP =4Hz), 149.37 (s,

15

1C), 189.17 (s, 1C). 31P {1H} NMR (C6D6, 25 °C, 202 MHz) of 7·PiBu3: δ 5.26 (s, 1P). Anal.

Calcd. for C26H41N2NiOP. C: 64.09, H: 8.48, N: 5.75. Found: C: 64.53, H: 8.38, N: 5.70.

Figure S15. 1H NMR of 7·PiBu3 in C6D6

16

Figure S16. 13C{1H} NMR of 7·PiBu3 in C6D6

17

Figure S17. 31P{1H} NMR of 7·PiBu3 in C6D6

Synthesis of 8. The monoarylated ligand 1b was synthesized according to previously reported

procedure with modification.4 Lithium diisopropylamide (4.717 g, 44.0 mmol) was dissolved in

100 mL of THF, hexane (1:5) mixture and cooled to –78 °C. To this solution, isobutyric acid (2.0

mL, 22.0 mmol) was added dropwise over 10 min. The mixture was stirred for 1 h at room

temperature and aliquots were monitored using 1H NMR spectroscopy. Benzyl chloride (2.787

g, 22.0 mmol) was added to the reaction mixture dropwise at –40 °C, and stirred overnight at

room temperature. The reaction was quenched using cold 1M HCl(aq) until acidic and the

aqueous layer was extracted using diethyl ether (40 mL × 3). Volatiles were removed under

vacuum to obtain 2,2-dimethyl-3-phenylpropanoic acid (2.504 g, 64% yield) and was converted

to 2,2-dimethyl-3-phenylpropanoyl chloride (2.625 g, 96% yield) using SOCl2 (1.9 mL, 26.7mmol)

in DCM (50 mL), which was then used to synthesize 1b (4.063 g, 95% yield),and 8 (2.447 g,

58% yield), using synthetic methods for 1a and 3 as described above. 1H NMR (CDCl3, 25 °C,

125 MHz ) δ 5.83 (br. s. 1H), 7.46 (br. s. 3H), 8.28(br. s. 2H), 11.06 (br. s. 1H), 13.02 (br. s. 1H),

16.21 (br. s. 1H), 19.16 (br. s. 1H), 26.11 (br. s. 1H), 68.70 (br. overlapping s. 1H + 3H from

Me), 165.9 (br. s. 3H), 217.3 (br. s. 1H). 1H NMR (C6D6, 25 °C, 500 MHz ) of 8, δ 6.34 (br. s.

1H), 7.12 (br. s. 2H), 7.25 (br. s. 2H), 8.34 (br. s. 1H), 10.15 (br. s. 1H), 13.08 (br. s. 1H), 16.41

(br. s. 1H), 19.53 (br. s. 1H), 25.31 (br. s. 1H), 68.14 (br. s. 1H), 79.91 (br. s. 3H), 151.31 (br. s.

18

3H), 216.21 (br. s. 1H).13C NMR (CDCl3, 25 °C, 500 MHz ) δ -33.8 (s, 1C), 25.2 (s, 1C), 53.7(s,

1C), 60.9(s, 1C), 99.3(s, 1C), 101.7(s, 1C), 126.4(s, 1C), 129.0(s, 2C), 131.6(s, 2C), 144.3(s,

1C), 209.2(s, 1C), 230.0(s, 1C), 231.1(s, 1C), 400.1(s, 3C), 601.9(s, 3C), 856.8(s, 1C).

Elemental analysis gave consistently low and variable C values over five different

measurements. Anal. Calcd. for C40H38N4NiO2, C: 72.20, H: 5.76, N: 8.42. Best found: C: 70.93,

H: 5.62, N: 8.12

Figure S18. 1H NMR of 8 in CDCl3 , (* co-crystalized toluene, # residual 1b).

19

Figure S19. 1H NMR of 8 in C6D6 .* labels co-crystalized toluene, # residual 1b.

20

Figure S20. 13C{1H} NMR of 8 in CDCl3

Failed catalytic run with nickel black. Ni(COD)2 (1g, 3.63mmol) was dissolved in toluene (30 mL) and heated at 100 °C for 1 h, the resulting nickel black was collected in a frit and washed twice with toluene, followed by drying under vacuum, and used as catalyst in the arylation of 1a with iodobenzene under previously reported conditions5 in a Teflon-valve sealed Schlenk flask using Ni black in lieu of the normal catalyst. The resulting mixture was filtered and no reaction to product was observed by 1H NMR.

Effect of phosphines on C—H arylation with NaOtBu. Solutions of 1a (44 mg, 0.19 mmol),

NaOtBu (76 mg, 0.76 mmol) and PhI (240 mg, 1.17 mmol) and either NiI2(PPh3)2 (32 mg, 0.038

mmol) or NiI2(PiBu3)2 (27 mg, 0.038 mmol) as the precatalyst, in 1,4-dioxane (2 mL) were

heated in sealed 50 mL bombs for 17 h at 100 °C. Both reactions were cooled and quenched

with water, and extracted with diethyl ether. The organic phase was dried using MgSO4 and the

solvent was removed in vacuo. 1H NMR of the crude reaction mixture in C6D6 showed the same

ratio between products and which provide one source of support that the phosphine does not

affect the rate of catalysis when NaOtBu is used as the base.

21

Figure S21: comparison of 1H NMR spectra of using NiI2(PPh3)2 and NiI2(PiBu3)2 as catalyst after 17 h

of reaction time at 100 °C. Choice of phosphine does not affect the yield. (* residual 1,4-dioxane)

Catalytic arylation using NaOtBu as the base: Trifunctionalization of 1a to give 1d. NiI2

(12 mg, 0.038 mmol), 1a (44 mg, 0.19 mmol), NaOtBu (186 mg,1.90 mmol ), PhI (240 mg, 1.14

mmol), and 1,4-dioxane (2 mL) were combined and stirred in a sealed 50 mL bomb at 140 °C

for 48 h, at which point 1d was observed in 94% by NMR, with 6% difunctionalized 1c as the

side product. The reaction was quenched with distilled water (5 mL) and extracted with diethyl

ether (10 mL x 3). The combined organic layer was dried with MgSO4, and solvent removed in

vacuo affording an orange crude and was further purified on prep TLC (Hex: EtOAc, 10:1, Rf:

0.2) to give 1d as a yellow solid. 1H NMR (CDCl3, 25 °C, 300 MHz ) δ 3.36 (s, 6H, PhCH2),

6.57 (dd, 1H, 3JHH =8.4Hz, 4.2Hz), 6.92-7.03 (m, 9H), 7.18-7.49 (m, 10H{1H from 8-AQ, 9H from

Ph}), 7.20 (m, 6H), 7.27 (dd, 1H, 3JHH =8.1Hz), 7.34 (dd, 1H, 3JHH = 8.3Hz, 1.6Hz), 8.10 (dd, 1H 3JHH = 4.3Hz, 1.6Hz), 9.41 (dd, 1H, 3JHH = 7.8Hz, 1.2Hz), 10.21 (s, 1H, NH),

22

Figure S22: 1H NMR of 1d in CDCl3

Attempt to observe catalyst resting state under previously reported5 literature conditions.

Ni(OTf)2 (20 mg, 0.056 mmol, 20% catalyst loading), PPh3 (29 mg, 0.11 mmol), 1a (64 mg, 0.28

mmol), PivOH (11 mg, 0.11 mmol), DMSO (76 mg, 0.97 mmol), PhI (171 mg, 0.84 mmol), and

Na2CO3 (119 mg, 1.12 mmol) were combined in dioxane and heated in a sealed bomb at 160

°C for 16 h. Conversion of 1a to 1b and 1c was observed by 1H. Despite the large catalyst

loading, the 1H NMR featured no additional peaks associated with Ni species, either

diamagnetic or paramagnetic. The 31P{1H} NMR only showed a broadened peak for PPh3 and

the 19F NMR only showed free triflate anion at δ –78.5, as shown in Figure S23.

23

Figure S23: 1H NMR showing catalysis and formation of 1b and 1c under reported catalytic conditions,

but no observable Ni catalyst resting state, paramagnetic or diamagnetic.

24

Figure S24: 31P{1H} NMR showing free PPh3 and trace amounts of NiI2(PPh3)2 under reported catalytic

conditions.

25

Figure S25: 19F{1H} NMR showing formation of NaOTf immediately upon mixing under catalytic

condition,

Test for solubility of catalyst resting state. This test was performed to demonstrate that the

resting state of the catalyst is soluble under the catalytic conditions. Precatalyst 6·PPh3 (12 mg,

0.011 mmol) was combined with PPh3 (6 mg, 0.022 mmol), 1a (50 mg, 0.22 mmol), DMSO (60

mg, 0.76 mmol), Na2CO3 (48 mg, 0.44 mmol) and iodobenzene (134 mg, 0.66 mmol) in dioxane

(2 mL). The mixture was heated in a sealed bomb at 160 °C for 3 h. (JL951-1) An aliquot was

removed and the 1H NMR was performed and showed a 10% conversion to 1b. Half the mixture

was removed and filtered through Celite and added to another reaction bomb with added

Na2CO3 (24 mg, 0.22 mmol) to compensate for the base removed by filtration. Both the filtered

and original solution were resealed and heated an additional 16 h at 160 °C overnight. 1H NMR

both solutions showed nearly identical further conversions to both 1b and 1c, consistent with a

soluble resting state unaffected by filtration.

26

Figure S26: 1H NMR showing catalysis and formation of 1b and 1c under reported catalytic conditions.

Botttom spectra is after 3h, showing conversion to 1b. This sample was then divided into an unfiltered

an filtered sample. After heating for 16 both samples have the same conversion to 1b and 1c,

consistent with a soluble catalyst resting state.

Attempts to monitor the formation of any potential intermediate by omitting PhI. An

attempt was made to observe a potential catalyst resting state or intermediate by using previous

literature conditions5 for the conversion of 1a to 1b but in the absence of the reagent PhI. A

dioxane solution containing 6·PPh3 (40 mg, 0.076 mmol), PPh3 (20 mg, 0.076 mmol), 1a (35

mg, 0.152 mmol), DMSO (21 mg, 0.266 mmol), and Na2CO3 (32 mg, 0.304 mmol) was prepared

and the 1H NMR was obtained. The only Ni species observed was the broad peak for the t-Bu

peaks of 6·PPh3 in dioxane, at 7.8. The resonances of free PPh3 are broadened. The solution

was heated at 160 °C in a sealed bomb. Aliquots were taken after 90 min and 16 h, and the 1H NMR spectra were obtained. After 90 min no resonance remained for 6, but no new Ni

species could be observed. The 1H NMR remained unchanged after 15 h of heating. The results

suggest that under these conditions 6 reacts to give an NMR silent species. Spectra are shown

in Figure S27 and S28

27

Figure S27: 1H NMR showing 6·PPh3 (δ 7.8, W1/2 = 900 Hz) after heating under pseudo-catalytic

conditions, with the omission of the reagent PhI. Complex 6·PPh3 disappears, and no new Ni

species resonances are observed.

28

29

Figure S28: 1H NMR (top and bottom) showing no peaks to replace 6·PPh3 under reported catalytic

condition without PhI after 90 min, similar to Figure S27.

The deleterious effect of Na2CO3. To investigate if the disappearance of 6·PPh3 in attempt to

observe the resting state is due to Na2CO3, 6·PPh3 (40 mg, 0.076 mmol), PPh3 (20 mg, 0.076

mmol), 1a (35 mg, 0.152 mmol), and DMSO (21 mg, 0.266 mmol) were combined in dioxane (2

mL) and heated in a sealed bomb at 160 °C for 16 h. An aliquot was taken and filtered through

Celite before its 1H NMR spectrum was taken (Figure S29a), beside the diamagnetic peaks

associated with 1a and solvents, several new paramagnetic peaks are observed at: δ 1.3 (W1/2

= 500 Hz), 5.2 (W1/2 = 400 Hz), 8.7 (W1/2 = 200 Hz), 10.2 (W1/2 = 170 Hz) and 22 (W1/2 = 1500

Hz), likely due to the ligand exchange between solvents and 6·PPh3 resulting a mixture of 6

bearing either PPh3, DMSO, and/or dioxane as donor ligands, and is further supported by the 1H NMR of aliquot of reaction of 6·PPh3 (40 mg, 0.076 mmol) and DMSO (21 mg, 0.266 mmol)

in dioxane (2 mL) at 160 °C for 16 h (Figure S29b). The deleterious effect of Na2CO3 was

confirmed by heating 6·PPh3 (40 mg, 0.076 mmol), Na2CO3 (32 mg, 0.304 mmol) and DMSO

(21 mg, 0.266 mmol) in dioxane (2 mL) at 160 °C for 16 h. 1H NMR spectrum shows only

diamagnetic peaks associated with solvent and free PPh3 and no presence of 6 bearing solvent

molecules or PPh3 (Figure S29c).

Figure S29: 1H NMR spectra of a) Reaction of 6·PPh3, 1a, PPh3 in dioxane with added DMSO, after

heating 160 °C for 16 h. Signals associated with 6 remain; b) Heating of 6·PPh3 in dioxane with added

DMSO, showing the same Ni species peaks observed in a); c) The same reaction as b), but with

added Na2CO3. No NMR active Ni species is observed. The PivOH peak intensity is negligible.

30

Figure S30: 1H NMR showing the broad peak at δ 22 associated with 6, and its disappearance in the

presence of Na2CO3, as observed in Figure 29a,b,c.

Effect of varying [7·PiBu3] on rate of arylation. A stock solution (A) of 1a (180 mg, 0.79

mmol), iodobenzene (161 mg, 0.79 mmol), PiBu3 (5 mg, 0.025 mmol), and HMDSO (8 mg, 0.049

mmol) was prepared. Solution A (1068 mg) was used to dissolve 7·PiBu3 (32 mg, 0.066 mmol)

to make solution B. To 4 NMR tubes, 550 mg, 275 mg, 138 mg, and 69 mg of solution B were

added and topped to 0.5 mL using solution A. Initial 1H NMR spectrum were recorded at 298 K

before the probe was set to 363 K and initial rates were monitored using 1H NMR spectroscopy.

31

Graph S1: Effect of varying [7·PiBu3] on rate of arylation

Effect of varying [PhI] on rate of arylation. Stock solution A was made of 7·PiBu3 (30 mg,

0.0615 mmol), 1a (141 mg, 0.615 mmol), PiBu3 (16 mg, 0.0791 mmol), and HMDSO (10 mg,

0.0615 mmol) as internal standard in 3 mL of C6D6. 1.016g, 1 mL of the stock solution A was

used to dissolve 268 mg (1.31 mmol) of iodobenzene to make stock solution B. 642mg, 321mg,

160mg, and 80mg of stock solution B were added to 4 different NMR tubes so [PhI] is halved

in each tube, respectively. Then, each tube is topped to approximately 0.5mL with stock solution

A. Initial 1H NMR was recorded at 298K before the probe was set to 363K and initial rates were

monitored using 1H NMR spectroscopy.

y = 0.0205x + 5E-05R² = 0.9988

0

0.0002

0.0004

0.0006

0.0008

0.001

0.0012

0.0014

0.0016

0 0.01 0.02 0.03 0.04 0.05 0.06 0.07

Kobs

[7·PiBu3] (mol/L)

Kobs vs [7·PiBu3]

32

Graph S2: Effect of varying [PhI] on rate of arylation

Graph S3: [1b] over time formed from arylation of 7·PiBu3

y = 0.015321x + 0.000635R² = 0.997640

0

0.002

0.004

0.006

0.008

0.01

0.012

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Ko

bs

[PhI] mol/L

kobs vs [PhI]

0

0.002

0.004

0.006

0.008

0.01

0.012

0.014

0.016

0.018

0.02

0 50 100 150 200 250 300 350 400 450

[1b

] m

ol/

L

Time (min)

[1b] vs Time

33

Effect of varying [PiBu3] on rate of arylation

Stock solution A was made of 7·PiBu3 (30 mg, 0.0615 mmol), 1a (141 mg, 0.615 mmol),

iodobenzene (101mg, 0.495 mmol), and HMDSO (10 mg, 0.0615 mmol) as internal standard in

3 mL of C6D6. 1 mL of stock solution A was used to dissolve (33 mg, 0.163 mmol)of PiBu3 to

make stock solution B. 538 mg, 269 mg, 67 mg, 34 mg, was added to 4 NMR tubes so that

[PiBu3] is halved each time. Then each NMR sample was topped to 0.5 mL with stock solution

A. Initial 1H NMR was recorded at 298K before the probe was set to 363 K and initial rates were

monitored using 1H NMR spectroscopy.

Graph S4. Effect of varying 1/[PiBu3] on kobs.

Conditions of kinetic studies to construct Hammett Plot

A stock solution was made by dissolving 7·PiBu3 (30 mg, 0.0615 mmol), 1a (141 mg, 0.615

mmol), PiBu3 (16 mg, 0.0791 mmol), and HMDSO (10 mg, 0.0615 mmol) as internal standard

in 3 mL of C6D6. 508 mg of stock solution was added in each of the 5 NMR tubes charge with

different aryl iodides (0.162mmol). Initial 1H NMR spectra were recorded at 298 K before the

probe was set to 363K and initial rates were monitored using 1H NMR spectroscopy.

y = 0.000058x + 0.000725R² = 0.992702

0

0.001

0.002

0.003

0.004

0.005

0.006

0.007

0 20 40 60 80 100 120

Ko

bs

1/[PiBu3]

Kobs vs 1/[PiBu3]

34

Graph S5. Formation of different arylation products overtime using substituted 4-iodoarenes.

Computational details. All calculations were performed using Gaussian 16.6 Geometry

optimizations, vibrational frequency and single point energy calculations were performed using

the BP86 functional in gas phase with the Def2Svp basis set. The nature of all stationary points

was confirmed by the number of imaginary frequencies. All minima have zero imaginary

frequency, and all transition states have only one imaginary frequency.

Gas phase energies are given in the discussion section of the manuscript, and were

found to correlate well with the experimentally observed rates. The SMD solvation model was

also used in single-point energy calculations to incorporate solvent effects with benzene as the

solvent, but were not found to give any improvement in fit to the experimental rates. These

energies are also given in the supplementary information for completeness.

y = 0.000055x - 0.000039

y = 0.000094x - 0.000046

y = 0.000072x + 0.000055

y = 0.000208x + 0.000053

y = 0.000023x + 0.000018

-0.0005

0

0.0005

0.001

0.0015

0.002

0.0025

0.003

0.0035

0.004

0.0045

0.005

0 5 10 15 20 25 30 35

[1-R

] m

ol/

L

Time (min)

[1-R] vs Time

4-H

4-OMe

4-COOEt

4-NMe2

4-CF3

35

Scheme S1: Calculated Gibbs free energies and enthalpies for solvation of 5 with DMF to give

a) dinuclear complexes and b) mononuclear complexes. Only the formation of mono-5·DMF

is favourable. c) The calculated energetics of the experimentally observed equilibrium between

mono-5·DMF and 3 and 6·2DMF in DMF.

36

Scheme S2: DFT computated energies (in gas phase and in benzene) of oxidative addition of

para-substituted iodoarenes to 7·PiBu3.

Gas phase Gas phase

sum of electronic and thermal enthalpies (Hartree)

sum of electronic and thermal free energies (Hartree)

complex 5 -5161.971673 -5162.11787

di-5•DMSO -5714.87706 -5715.039328

di-5•2DMSO -6267.793616 -6267.98031

mono 5 -2580.970604 -2581.057024

mono 5•DMSO -3133.898312 -3134.000308

mono 5•2DMSO -3686.745928 -3686.8623

complex 3 -2961.429693 -2961.529925

6•2DMSO -5506.928966 -5507.076332

DMSO -552.903619 -552.939016

37

di-5•DMF -5410.192527 -5410.356073

di-5•2DMF -5658.413327 -5658.591062

Mono-5•DMF -2829.213113 -2829.316434

Mono-5•2DMF -3077.435396 -3077.558383

6•2DMF -4897.534542 -4897.688282

DMF -248.2252 -248.261204

In solution (SMD: benzene) single point energy (Hartree)

7•PiBu3 -3048.451996 -3048.555701 -3049.118269

PiBu3 -814.091163 -814.158018 -814.4777824

INT-1 -2234.302286 -2234.361669 -2234.582119

4-NMe2 iodobenzene

-663.009809 -663.05978 -663.1882789

4-OMe iodobenzene

-643.619655 -643.664613 -643.7552008

Iodobenzene -529.213599 -529.252425 -529.3147435

4-CO2Et iodobenzene

-796.144131 -796.198312 -796.323371

4-CF3 iodobenzene

-865.996294 -866.045722 -866.1046338

TS1 (Ar = 4-PhNMe2)

-2897.331064 -2897.419765 -2897.787303

TS1 (Ar = 4-PhOMe)

-2877.939945 -2878.023916 -2878.353324

TS1 (Ar=Ph) -2763.533477 -2763.611247 -2763.9125

TS1 (Ar = 4-PhCO2Et)

-3030.464295 -3030.557413 -3030.921643

TS1 (Ar = 4-Ph CF3)

-3100.315748 -3100.40419 -3100.702316

INT-2 (Ar = 4-PhNMe2)

-2897.355673 -2897.444354 -2897.812321

INT-2 (Ar = 4-PhOMe)

-2877.965852 -2878.049682 -2878.379719

INT-2 (Ar=Ph) -2763.560406 -2763.638029 -2763.939911

INT-2 (Ar = 4-PhCO2Et)

-3030.491469 -3030.584587 -3030.949226

INT-2 (Ar = 4-Ph CF3)

-3100.344084 -3100.432299 -3100.730841

TableS1: Calculated energies of complexes in DFT calculations

38

XYZ coordinates for computations 40 PiBu3 P -0.00014800 -0.00037500 -0.36472000 C -0.38697100 1.62799500 0.52043800 H -1.48190700 1.62536100 0.70821500 H 0.09982000 1.63778600 1.52395400 C -1.21685400 -1.14928500 0.52103000 H -0.66703600 -2.09610800 0.70921700 H -1.46860300 -0.73208900 1.52435800 C 1.60322000 -0.47958000 0.52100400 H 2.14766900 0.47003000 0.71057800 H 1.36771200 -0.90755900 1.52374000 C 2.52604100 -1.43440700 -0.27004900 H 2.74998200 -0.93771000 -1.24341400 C -2.50603400 -1.46957900 -0.26926900 H -2.18893100 -1.91092600 -1.24340400 C -0.01952900 2.90433200 -0.27018600 H -0.55937700 2.84971000 -1.24480300 C 3.85871100 -1.63744600 0.47354800 H 4.55396300 -2.27842400 -0.10915900 H 4.37114600 -0.67111900 0.66569100 H 3.69571600 -2.13035800 1.45719400 C 1.85893000 -2.78315900 -0.58786200 H 1.58987300 -3.32917700 0.34353600 H 0.93292600 -2.64918400 -1.18644100 H 2.53887700 -3.43838000 -1.17216000 C -3.34800100 -2.52265300 0.47386200 H -4.25141200 -2.80313200 -0.10833700 H -2.76760600 -3.45009700 0.66431800 H -3.69224900 -2.13606900 1.45830400 C -3.34028900 -0.21673300 -0.58495200 H -3.67763000 0.28833200 0.34732600 H -2.76152100 0.51875700 -1.18312300 H -4.24830700 -0.47694200 -1.16877000 C -0.51172800 4.16027500 0.47176800 H -0.30288600 5.08263400 -0.11083100 H -1.60526400 4.12097800 0.66132100 H -0.00571900 4.26601000 1.45658500 C 1.48283200 3.00081200 -0.58449400 H 2.08800500 3.04127200 0.34833100 H 1.83133300 2.13160000 -1.18177500 H 1.71167200 3.91699900 -1.16868700 20 4-NMe2 iodobenzene xyz C -2.31036400 -0.00000200 -0.00002700 C -1.56725200 1.21714800 -0.00002600 C -0.16522800 1.21530900 0.00000300 C 0.53980000 0.00001100 0.00001500

39

C -0.16522000 -1.21529500 -0.00000600 C -1.56724400 -1.21714600 -0.00003400 H -2.08389700 2.18665400 -0.00005800 H 0.37415000 2.17456500 0.00001100 H 0.37416200 -2.17454800 -0.00000100 H -2.08387700 -2.18665800 -0.00005700 I 2.67173300 -0.00000100 0.00000400 N -3.69760300 -0.00000400 -0.00002900 C -4.42342000 -1.25768400 0.00002800 H -4.19586400 -1.87740900 0.89876400 H -5.51038400 -1.05340200 0.00025400 H -4.19620900 -1.87734500 -0.89885000 C -4.42343200 1.25767300 0.00001600 H -4.19628200 1.87731700 -0.89888800 H -5.51039600 1.05339100 0.00030600 H -4.19583300 1.87743300 0.89872100 16 4-OMe iodobenzene C 2.60534700 0.27650900 -0.00029500 C 1.80229900 1.44130500 -0.00013400 C 0.40611400 1.34445800 -0.00004000 C -0.20419500 0.07426200 -0.00013900 C 0.57967200 -1.08889600 -0.00041900 C 1.98452900 -0.99178700 -0.00053900 H 2.30103600 2.42247800 -0.00002800 H -0.20499100 2.25933500 0.00014100 H 0.10693500 -2.08246400 -0.00058400 H 2.57885000 -1.91646300 -0.00092500 I -2.33008100 -0.07796500 0.00010000 O 3.95332100 0.48004800 -0.00036500 C 4.81115300 -0.65061900 0.00081300 H 5.84526600 -0.25715200 0.00200900 H 4.66451300 -1.28253600 0.90643400 H 4.66660000 -1.28284200 -0.90493500 12 Iodobenzene C 3.37028600 0.00001800 -0.00000000 C 2.66436100 1.21554800 0.00000200 C 1.25754200 1.22499600 -0.00000200 C 0.56711800 -0.00003300 0.00000100 C 1.25757000 -1.22501400 0.00000200 C 2.66441600 -1.21551600 -0.00000200 H 4.47145500 0.00006100 0.00000200 H 3.20866700 2.17353900 -0.00000100 H 0.70740500 2.17768800 -0.00000200 H 0.70751400 -2.17775300 0.00000400 H 3.20870900 -2.17351400 -0.00000300 I -1.56587800 -0.00000000 -0.00000000

40

21 4-COOEt iodobenzene C 1.54295200 0.47520600 -0.00005400 C 0.66645700 1.58124800 0.00007200 C -0.72299600 1.39351900 0.00008700 C -1.23547300 0.08225300 -0.00001300 C -0.37869200 -1.03436700 -0.00012900 C 1.01014400 -0.83202100 -0.00015200 H 1.09969800 2.59343300 0.00015800 H -1.40057900 2.26003800 0.00018300 H -0.78967100 -2.05474400 -0.00020400 H 1.69224800 -1.69462000 -0.00024400 I -3.34272600 -0.21724100 0.00001800 C 3.01550400 0.75063500 -0.00005800 O 3.75207800 -0.39147000 0.00001100 O 3.50822300 1.86841700 -0.00011600 C 5.18914100 -0.21547100 0.00002000 H 5.47574700 0.38343500 -0.89136200 H 5.47571300 0.38357400 0.89131800 C 5.83211700 -1.59108700 0.00014600 H 6.93665400 -1.49089100 0.00016700 H 5.53864100 -2.17069100 0.89897200 H 5.53868700 -2.17083000 -0.89860400 15 4-CF3 iodobenzene C -2.01640100 0.00040500 -0.03795000 C -1.31066500 -1.21761400 -0.03349200 C 0.09320300 -1.22385500 -0.02008400 C 0.78639800 0.00016500 -0.01180800 C 0.09342800 1.22424300 -0.02010300 C -1.31050400 1.21823900 -0.03347300 H -1.86017300 -2.17092100 -0.04790800 H 0.64014000 -2.17809300 -0.01948000 H 0.64047400 2.17841900 -0.01950200 H -1.85990100 2.17158900 -0.04779500 I 2.91380900 -0.00007600 0.00705800 C -3.52959300 0.00004300 0.00460800 F -3.99146100 -0.00669700 1.28300600 F -4.05051300 1.09805400 -0.59846200 F -4.04998300 -1.09210300 -0.60960500 72 Square planar Ni(II) CH activation adduct with PiBu3 xyz Ni 0.31616100 0.41129400 -0.08182700 N 2.02463900 1.20679800 0.10182300 N 1.36337000 -1.27641400 -0.20625000 O 3.19529300 3.20131100 0.42515800 C -0.30885800 2.24349600 0.14552500 C 0.80944400 3.26216100 -0.14029200 C 0.65974700 4.54924600 0.69265900

41

C 0.84917400 3.62283600 -1.64686000 C 2.15303100 2.58393300 0.18447900 C 3.08892200 0.32702400 0.20388900 C 4.44936100 0.61515900 0.44249000 C 5.40143300 -0.43326900 0.48226300 C 5.05040000 -1.76803300 0.28630400 C 3.68718300 -2.10259100 0.04091700 C 2.70999400 -1.04692400 0.01548200 C 3.21997400 -3.42840000 -0.19191600 C 1.86922500 -3.64247100 -0.43765200 C 0.97796300 -2.54277600 -0.43587700 H -0.08976000 -2.70796000 -0.63563800 H 1.47423500 -4.65086700 -0.63316400 H 3.93564500 -4.26641100 -0.18161500 H 5.80575300 -2.56871700 0.31524800 H 6.45600200 -0.17419200 0.67200500 H 4.73983800 1.66238900 0.58966400 H -0.60949800 2.29441000 1.21962200 H -1.20667800 2.48583800 -0.46332500 H 0.59919200 4.32063900 1.77752800 H -0.25741300 5.10583500 0.40479800 H 1.54251600 5.20450400 0.53932500 H 1.69788100 4.30277000 -1.86770700 H -0.09245700 4.13133400 -1.94799700 H 0.96447100 2.71179600 -2.27055300 P -1.72385100 -0.39970600 -0.06940300 C -2.02096000 -1.62769900 1.31817300 H -3.06265700 -2.00370300 1.21822800 H -1.35470400 -2.49895900 1.13470500 C -2.19135700 -1.39169100 -1.60659000 H -2.03684500 -2.46638700 -1.36378200 H -3.28056500 -1.27589100 -1.78568500 C -3.14629000 0.80672400 0.14576300 H -2.74475800 1.60202000 0.80716900 H -3.27770700 1.29488400 -0.84582600 C -4.52338600 0.36611400 0.70353200 H -4.35248400 -0.13545800 1.68314100 C -1.40641200 -1.02290600 -2.88610800 H -0.32176400 -1.08647500 -2.63939500 C -1.77683000 -1.08960900 2.75008000 H -2.30596400 -0.11260100 2.84738300 C -2.39101000 -2.04974300 3.78603700 H -2.23707500 -1.67366400 4.81910000 H -3.48337800 -2.18060600 3.63282500 H -1.91942700 -3.05471800 3.72357300 C -0.28571700 -0.84777000 3.03525100 H 0.17307300 -0.17682700 2.27415400 H -0.13881800 -0.38640200 4.03378500 H 0.28060000 -1.80425500 3.01690300 C -1.70720600 -2.03429400 -4.00627900 H -2.78372500 -2.01692400 -4.28500400

42

H -1.12247500 -1.80212700 -4.92090400 H -1.45675400 -3.07259100 -3.70164600 C -1.68824000 0.41806700 -3.34128300 H -1.38099400 1.14907000 -2.56422100 H -1.12094700 0.66244800 -4.26324800 H -2.76814800 0.56978700 -3.56126000 C -5.36905400 1.62546700 0.98426500 H -5.57809400 2.18279700 0.04527000 H -6.34597500 1.35816200 1.43919800 H -4.85145100 2.32089700 1.67730900 C -5.30785200 -0.60904200 -0.19138200 H -5.46712300 -0.18477700 -1.20687400 H -4.80084800 -1.58825700 -0.30934900 H -6.30996800 -0.81268300 0.24096500 32 Tri-coordinate Ni(II) CH activated product without phosphine support xyz Ni 0.56824600 -1.41073900 -0.10912200 N 0.67089300 0.38931900 -0.05327900 N -1.34526000 -1.24126400 0.00380500 O 2.07679200 2.22925800 -0.11883900 C 2.44306300 -1.39073900 -0.35015500 C 3.05247900 -0.03349200 0.04971800 C 4.23823000 0.39308700 -0.83626000 C 3.48261200 -0.04247500 1.53826400 C 1.91700100 1.01014900 -0.07040500 C -0.56997400 1.02095200 -0.03633000 C -0.85058000 2.40007600 -0.04152900 C -2.19740500 2.84478500 -0.00721600 C -3.27722000 1.96350200 0.02875700 C -3.03494000 0.55851000 0.03330500 C -1.67658300 0.10080900 0.00241800 C -4.05276600 -0.44234500 0.06295000 C -3.69982400 -1.78818700 0.06194300 C -2.33110000 -2.15134200 0.03397600 H -2.02749300 -3.21178500 0.03912600 H -4.46521600 -2.57844500 0.08488100 H -5.11136500 -0.13722900 0.08587000 H -4.31368900 2.33420800 0.05095300 H -2.38659400 3.93047600 -0.01198500 H -0.01261100 3.10731100 -0.07255800 H 2.59758200 -1.59979800 -1.43637600 H 2.86037800 -2.24257800 0.24313600 H 3.95918400 0.38555000 -1.91074400 H 5.09821700 -0.29559700 -0.69904600 H 4.56036400 1.42366500 -0.57955800 H 3.81917000 0.96448800 1.85996300 H 4.31935800 -0.75712200 1.69077100 H 2.64010500 -0.35264300 2.19141800 52

43

Transition state Ni NMe2 Oxidative addition xyz H -4.15044200 2.53435000 -3.20456600 H -2.65323000 0.88426600 -4.40350800 H -1.13198300 -0.59660500 -3.06344200 Ni -0.69581100 -0.94669300 0.08330400 C -4.27640300 2.79163100 -0.44176600 C -4.19875200 2.73844000 0.94907500 H -4.83251800 3.40929900 1.55196900 C -3.33904200 1.83990300 1.62821100 H -3.30389800 1.79606400 2.72323200 C -0.17637900 -2.05749000 1.57900100 C -1.43560700 -0.26503500 2.72808700 O -2.03379600 0.28371300 3.65771700 N -1.62237800 0.01384000 1.38117700 C -2.51011100 0.96442200 0.89582900 C -2.56701200 1.02101600 -0.54054100 C -3.46081600 1.91990400 -1.21970800 C -3.47774400 1.86474500 -2.64435700 C -2.65520700 0.96011500 -3.30551300 C -1.79693200 0.12040200 -2.55483600 N -1.73700000 0.14689800 -1.21418300 H -4.96233200 3.48709700 -0.95008800 I 0.74088000 -2.29733700 -1.61329800 C -0.33322700 -1.32466200 2.91879800 C 0.95751600 -0.55672700 3.29558100 H 0.80297300 0.03753900 4.21995300 H 1.79172000 -1.26943000 3.47421100 H 1.26281800 0.13295600 2.48203100 C -0.72597900 -2.26967200 4.07157100 H 0.09282600 -2.98688700 4.29230400 H -0.94603400 -1.68070200 4.98664200 H -1.63669400 -2.85281100 3.82033800 H -0.91246100 -2.89285700 1.50005300 H 0.84252500 -2.48775900 1.45928400 C 1.77595600 -0.52913600 -0.83498100 C 2.81873700 -0.71847200 0.08856800 C 1.60738000 0.71889700 -1.46115200 C 3.63943100 0.35831300 0.44660200 H 2.99152500 -1.70061800 0.55282000 C 2.42478400 1.79626900 -1.09914600 H 0.82648000 0.87343000 -2.21856300 C 3.46005300 1.65266400 -0.12673000 H 4.42920500 0.17944100 1.18858200 H 2.24451000 2.76436700 -1.58552300 N 4.26042000 2.72112300 0.23814900 C 5.31095100 2.53855400 1.22581600 H 6.08217300 1.80496000 0.89370300 H 5.81961700 3.50450600 1.40158900 H 4.90926500 2.18511100 2.20327900 C 4.05689700 4.02418900 -0.37250200 H 4.77032800 4.74780100 0.06351500

44

H 4.22342600 4.00640700 -1.47487000 H 3.02838500 4.41400700 -0.19380700 48 Transition state Ni OMe Oxidative addition xyz H 4.46710500 -3.05156400 2.07014700 H 2.69503500 -4.35161800 0.81695700 H 0.91495300 -3.10684200 -0.44142400 Ni 0.40004600 0.01296000 -0.91895800 C 4.62224200 -0.27904100 2.10769600 C 4.52716500 1.10508000 1.97459300 H 5.27141900 1.74855700 2.47162000 C 3.50930500 1.72653200 1.20900500 H 3.45965500 2.81620300 1.09789600 C -0.32994300 1.43285300 -2.01082200 C 1.23932600 2.69317800 -0.57298700 O 1.92571000 3.65316700 -0.21291000 N 1.48116800 1.36744600 -0.23992000 C 2.53535400 0.94160200 0.55777900 C 2.61111500 -0.48761500 0.70090000 C 3.66223500 -1.10943200 1.46036400 C 3.67742800 -2.53434900 1.50133300 C 2.70420100 -3.25111400 0.81498400 C 1.69900300 -2.55412700 0.10152000 N 1.63641500 -1.21470900 0.04688200 H 5.42943100 -0.74295900 2.69561200 I -1.26041300 -1.75555700 -1.84159100 C -0.04278800 2.81949700 -1.41857100 C -1.16773700 3.26430300 -0.45211900 H -0.90754400 4.22754500 0.03341100 H -2.12156500 3.39969500 -1.00683000 H -1.33411900 2.50683900 0.34126600 C 0.16302000 3.89737100 -2.50123300 H -0.77604300 4.07553100 -3.06686100 H 0.48706800 4.84954200 -2.03120100 H 0.94918800 3.59524300 -3.22451900 H 0.23457100 1.28788700 -2.96282200 H -1.41144200 1.29251100 -2.23096500 C -1.94313000 -0.85330500 0.03744300 C -2.99742200 0.07118300 -0.01562800 C -1.53211300 -1.40630600 1.26792300 C -3.60281200 0.50919200 1.17655600 H -3.34831400 0.47515800 -0.97648800 C -2.13420600 -0.96683100 2.45049200 H -0.73359600 -2.15944800 1.31459400 C -3.17124400 -0.00287500 2.42037700 H -4.41164100 1.25067600 1.11470600 H -1.81233700 -1.36297400 3.42541500 O -3.68871000 0.35380700 3.62684400 C -4.72374900 1.32638600 3.66451100 H -4.97747800 1.46854300 4.73180600

45

H -4.39131400 2.30003000 3.23861700 H -5.63296800 0.98507200 3.11930600 44 Transition state Ni PhI Oxidative addition xyz H 4.30786600 -3.63176100 0.22209900 H 2.08239500 -4.55444000 -0.55015400 H 0.15621400 -2.98429800 -0.90538200 Ni -0.10421000 0.19596500 -0.65658500 C 4.80242300 -0.93476100 0.65987600 C 4.83831300 0.45173500 0.79626500 H 5.77561900 0.94039500 1.10868700 C 3.71090500 1.27022800 0.53614700 H 3.76143700 2.36158000 0.62882500 C -0.97156800 1.84282300 -1.17984200 C 1.12330700 2.70151900 -0.18421300 O 2.00291500 3.52859300 0.06817400 N 1.29515700 1.32355600 -0.17260400 C 2.49072800 0.68737800 0.13609400 C 2.43471600 -0.74414500 0.00732000 C 3.59125400 -1.56379900 0.25062800 C 3.44570100 -2.96742200 0.04894900 C 2.22375200 -3.47737800 -0.37383900 C 1.13451700 -2.59581100 -0.57824800 N 1.22074500 -1.27054100 -0.38671900 H 5.69361000 -1.55181400 0.85327000 I -2.17391800 -1.25627100 -1.22087900 C -0.33818300 3.06801100 -0.50655800 C -1.02253900 3.38621300 0.84545900 H -0.50248800 4.22054300 1.35974100 H -2.08098000 3.68350500 0.68161800 H -1.01178600 2.50274600 1.51637800 C -0.36490400 4.31973900 -1.40584400 H -1.40726800 4.66218200 -1.57774600 H 0.21008800 5.14079300 -0.92864600 H 0.09848200 4.11499700 -2.39369700 H -0.77338700 1.85058300 -2.27840500 H -2.07362900 1.81197200 -1.03149900 C -2.10299200 -0.68809100 0.90115300 C -3.00563300 0.29379800 1.34665000 C -1.36982000 -1.47911200 1.80422900 C -3.12356700 0.52602400 2.72867200 H -3.60027500 0.88313900 0.63367500 C -1.49989000 -1.22626600 3.18105300 H -0.69247100 -2.26794900 1.44984500 C -2.37110600 -0.22556000 3.64775200 H -3.81690600 1.30566800 3.08221800 H -0.90920300 -1.82586700 3.89174900 H -2.46889300 -0.03719500 4.72799500 53

46

Transition state Ni COOEt oxidative addition xyz H 4.21707700 -1.53194400 -4.08367500 H 3.42621900 0.86849400 -4.19015400 H 2.15554300 1.83201300 -2.25185500 Ni 1.31458000 0.61727400 0.58765400 C 3.82136900 -3.20178300 -1.90082600 C 3.53469400 -3.85330200 -0.70291400 H 3.86117600 -4.89667000 -0.56294600 C 2.84221900 -3.22005100 0.35949300 H 2.64150100 -3.74079600 1.30327700 C 0.84423200 0.88900100 2.44259700 C 1.40893700 -1.51945200 2.43863000 O 1.69306800 -2.61840000 2.92060500 N 1.72714700 -1.10577200 1.15154000 C 2.40364600 -1.88724900 0.22268900 C 2.67864500 -1.20776100 -1.01456600 C 3.40226000 -1.85151500 -2.07769100 C 3.66439200 -1.07750000 -3.24546800 C 3.22974900 0.24129100 -3.30753200 C 2.51437800 0.79042900 -2.21572800 N 2.23180300 0.09549700 -1.10344700 H 4.37201100 -3.70728200 -2.70923500 I 0.51188800 2.97056400 -0.12004100 C 0.60072900 -0.43587100 3.17802600 C -0.88598400 -0.86068900 3.09584500 H -1.03348700 -1.85889700 3.55704100 H -1.52671300 -0.12962400 3.63480800 H -1.22943400 -0.91074000 2.04206500 C 1.04312100 -0.38591400 4.65380800 H 0.41257300 0.32134600 5.23301200 H 0.96156300 -1.39583100 5.10745500 H 2.10057900 -0.06064400 4.74582300 H 1.76628600 1.38924900 2.82501700 H -0.00555200 1.59554900 2.57129900 C -1.05639500 1.48583600 -0.44331900 C -2.13557700 1.45442500 0.46023700 C -1.09132800 0.77308400 -1.65803100 C -3.24160400 0.64339100 0.16690800 H -2.11375600 2.04224500 1.38925600 C -2.20338800 -0.03241600 -1.93306600 H -0.25950200 0.82745200 -2.37364900 C -3.28484600 -0.10898400 -1.02731500 H -4.08592900 0.59444600 0.86966800 H -2.25512500 -0.61900500 -2.86325100 C -4.44153000 -0.98556700 -1.39248700 O -4.51589400 -1.63306400 -2.42614400 O -5.40978200 -0.98191100 -0.43892600 C -6.56581300 -1.81088600 -0.71022900 H -7.02739800 -1.47846600 -1.66517300 H -6.22530100 -2.85697500 -0.86786600 C -7.52003200 -1.68694300 0.46437700

47

H -7.85223200 -0.63782500 0.60242500 H -8.41859000 -2.31249000 0.28730200 H -7.04283700 -2.02773100 1.40565800 47 Transition state Ni CF3 oxidative addition xyz H -3.88455300 2.74922600 -3.46280300 H -2.63080700 0.81984400 -4.51365300 H -1.34813900 -0.75958900 -3.04418100 Ni -0.98542600 -0.93070800 0.13259200 C -3.99485300 3.22482600 -0.72956300 C -3.93599800 3.26435900 0.66212700 H -4.47156500 4.06089400 1.20383700 C -3.21723800 2.30600500 1.41976100 H -3.19753700 2.34016100 2.51550300 C -0.61913200 -1.98096900 1.71327900 C -1.64527400 0.03841000 2.70697200 O -2.17805300 0.72695600 3.57998900 N -1.77242200 0.24516500 1.33921400 C -2.51529000 1.27132500 0.76829500 C -2.55398000 1.22782500 -0.66864800 C -3.30571400 2.19126200 -1.42722200 C -3.31920300 2.03386200 -2.84377000 C -2.62983300 0.97563000 -3.42428100 C -1.90660700 0.08018500 -2.59935300 N -1.85315200 0.19778600 -1.26377200 H -4.57013400 3.97111200 -1.29906700 I 0.32505700 -2.52430200 -1.42192300 C -0.70050700 -1.14376000 2.99686600 C 0.67481400 -0.53142500 3.35893200 H 0.58575000 0.13737800 4.23953100 H 1.40279100 -1.33476600 3.60416200 H 1.08346900 0.06064800 2.51425500 C -1.24029000 -1.94747600 4.19638500 H -0.53072300 -2.75076100 4.48696100 H -1.39573300 -1.27296000 5.06423200 H -2.21671000 -2.41879400 3.95787600 H -1.45205500 -2.72336400 1.67230200 H 0.34021600 -2.54048400 1.64453600 C 1.58508700 -0.86644000 -0.76015200 C 2.56876700 -1.12781900 0.21099000 C 1.56345800 0.34739200 -1.47254800 C 3.51052100 -0.13122700 0.50991700 H 2.59812200 -2.08824500 0.74536800 C 2.50923200 1.33430500 -1.15920100 H 0.80928200 0.53870900 -2.24804200 C 3.48504100 1.10145300 -0.16938100 H 4.27017200 -0.31762600 1.28380600 H 2.48221300 2.29801700 -1.68961900 C 4.54116900 2.14782800 0.11286700 F 5.00428000 2.06653300 1.38446100

48

F 5.61478200 2.00365600 -0.71043400 F 4.06629800 3.40412400 -0.07483500 52 Ni (IV) NMe2 xyz H 3.62862700 -2.63911600 -3.57385800 H 2.42666500 -0.62594000 -4.51898500 H 1.14911200 0.89771200 -2.94422800 Ni 0.59147400 0.81340300 0.21083300 C 3.63745800 -3.32772000 -0.88077200 C 3.50051200 -3.49138800 0.49455600 H 3.98597500 -4.34728500 0.99039500 C 2.75157100 -2.58916300 1.29466300 H 2.66114000 -2.72812600 2.37854400 C 0.11248600 1.68741900 1.88820700 C 1.10715500 -0.44452600 2.70267500 O 1.56683300 -1.23759200 3.52469900 N 1.37233400 -0.48294200 1.33551400 C 2.12136900 -1.47583700 0.70524400 C 2.25360100 -1.29747800 -0.71608600 C 3.00631300 -2.21947600 -1.51968000 C 3.06282000 -1.95654400 -2.91884900 C 2.40308100 -0.85029000 -3.44217000 C 1.68249200 0.00600800 -2.57222600 N 1.61505000 -0.20729100 -1.25597200 H 4.22141300 -4.03956500 -1.48473700 I 0.23413200 2.93785800 -1.15816900 C 0.17294500 0.72306400 3.07424800 C -1.20978800 0.12625800 3.43239600 H -1.10652100 -0.59379700 4.26976300 H -1.90286600 0.93411100 3.74891800 H -1.66454300 -0.39944800 2.57035700 C 0.75669100 1.43421000 4.31880100 H 0.07551500 2.23817400 4.66696500 H 0.89111200 0.69590500 5.13621900 H 1.74699700 1.88665500 4.10294100 H 0.96242900 2.40696300 1.89672600 H -0.83687200 2.24878200 1.80639000 C -1.14997300 0.03810000 -0.02035500 C -2.34344500 0.78119300 -0.00565600 C -1.21191200 -1.34948500 -0.22661300 C -3.57783800 0.14971400 -0.22757300 H -2.33510500 1.86751100 0.15859200 C -2.44637100 -1.98537200 -0.44887600 H -0.30953700 -1.97834400 -0.21807800 C -3.66626700 -1.25188500 -0.46534600 H -4.48084700 0.77611100 -0.22542600 H -2.44212600 -3.07287700 -0.60702700 N -4.88614800 -1.87405200 -0.69992900 C -4.94397800 -3.31635500 -0.85187200 H -4.61125700 -3.86252000 0.06359800

49

H -5.98538400 -3.62082400 -1.06777200 H -4.31051500 -3.66862700 -1.69774900 C -6.11641800 -1.10755400 -0.61809500 H -6.12555300 -0.26062600 -1.34142500 H -6.97322400 -1.76297300 -0.86329500 H -6.29326700 -0.68022000 0.39822000 48 Ni(IV) OMe xyz H 4.27186100 0.24089500 -3.76648500 H 2.55676900 2.09180200 -3.91901000 H 0.81838200 2.31461500 -2.08692000 Ni 0.19127900 0.61039700 0.55408700 C 4.38203200 -1.61648300 -1.70124800 C 4.24658500 -2.44198300 -0.58896400 H 4.94677900 -3.28070400 -0.44678300 C 3.23007500 -2.24468400 0.38202400 H 3.14343000 -2.89896300 1.25762500 C -0.59328300 0.43439900 2.33333100 C 0.96545300 -1.50484600 2.28277200 O 1.61393100 -2.44657700 2.73834400 N 1.28130400 -0.82459100 1.10792200 C 2.31838200 -1.17974300 0.24571400 C 2.44634800 -0.32169500 -0.90140800 C 3.47250400 -0.53284900 -1.88358000 C 3.50188700 0.36682000 -2.98786000 C 2.56028500 1.38605400 -3.07507800 C 1.58129900 1.51776900 -2.05868800 N 1.52985800 0.69684700 -1.00669200 H 5.17615800 -1.78690800 -2.44470500 I -0.73129600 2.96611600 0.22698700 C -0.29400300 -0.92914700 2.95810800 C -1.44356100 -1.94657900 2.75791000 H -1.16359700 -2.92614600 3.19631200 H -2.36365100 -1.58657600 3.26478100 H -1.67702600 -2.09639800 1.68585300 C -0.00795200 -0.77739100 4.47155100 H -0.91583000 -0.43560800 5.01042500 H 0.31073600 -1.75613000 4.88603300 H 0.80545400 -0.04656400 4.66164700 H 0.00242600 1.24680400 2.80789100 H -1.66292200 0.71514700 2.34359000 C -1.23171500 -0.35242100 -0.30208900 C -2.58909200 -0.02157000 -0.16511500 C -0.85848200 -1.43044400 -1.12838000 C -3.57465200 -0.75048800 -0.86226900 H -2.90908900 0.81688000 0.46850300 C -1.83816100 -2.15762100 -1.82225300 H 0.19186000 -1.73347900 -1.24896800 C -3.20526700 -1.82520800 -1.69821600 H -4.62684500 -0.45377000 -0.74400000

50

H -1.55584800 -3.00233400 -2.46957400 O -4.07906600 -2.59132400 -2.41490000 C -5.46479300 -2.30390200 -2.31904500 H -5.70294100 -1.27599500 -2.67698400 H -5.98159800 -3.03727800 -2.96690300 H -5.84203500 -2.41510200 -1.27654100 44 Ni (IV) PhI xyz H 4.56562000 -3.14430700 0.48233300 H 2.37844200 -4.41129900 0.43675700 H 0.22625200 -3.13929000 0.01673300 Ni -0.42742000 -0.03449000 -0.43536700 C 4.78473100 -0.39822400 0.11149500 C 4.66403500 0.97417500 -0.08590600 H 5.56661800 1.60592200 -0.07412000 C 3.40938100 1.60074700 -0.30536200 H 3.33348300 2.68220000 -0.46967000 C -1.58152600 1.39289300 -1.10603700 C 0.57195100 2.59952900 -0.79649200 O 1.37502900 3.52543700 -0.90683800 N 0.92626100 1.27108000 -0.56520500 C 2.23010600 0.83115000 -0.33781300 C 2.34176300 -0.58764500 -0.13091800 C 3.61406200 -1.21309300 0.09761000 C 3.61129800 -2.62301900 0.30211000 C 2.41040200 -3.32319900 0.27771800 C 1.20051500 -2.62182600 0.04757800 N 1.16786900 -1.30218900 -0.15484100 H 5.76704200 -0.86579500 0.28127900 I -2.09309000 -1.86335300 -1.05460600 C -0.95453500 2.77379000 -0.90964000 C -1.44493700 3.47860000 0.37857400 H -0.93755900 4.45834300 0.49137300 H -2.53967300 3.65586200 0.32341800 H -1.23953400 2.87260200 1.28233700 C -1.25245800 3.67917400 -2.12897800 H -2.33867200 3.89380300 -2.20265000 H -0.70200400 4.63643400 -2.01969200 H -0.92591600 3.20557500 -3.07812300 H -1.55800300 1.07559300 -2.17305700 H -2.61497000 1.30295000 -0.72268000 C -0.97472500 0.20144400 1.39000100 C -2.32001700 0.20572000 1.80203800 C 0.05707500 0.34983800 2.33271400 C -2.62445500 0.34706200 3.17048400 H -3.13773900 0.08282800 1.07909500 C -0.26412900 0.49273300 3.69909500 H 1.11632800 0.36660100 2.03755500 C -1.60219700 0.49143500 4.12273000 H -3.68132600 0.33525000 3.48355300

51

H 0.55363400 0.61280600 4.42844400 H -1.84764400 0.60388400 5.19054200 53 Ni (IV) COOEt xyz H -3.60706300 3.10668900 -3.58524800 H -2.47984100 1.07687100 -4.58532600 H -1.41713500 -0.62832100 -3.04085200 Ni -1.07851900 -0.78512200 0.14287000 C -3.75660200 3.62143700 -0.85761700 C -3.70449600 3.68826700 0.53150600 H -4.16328800 4.54422400 1.05167200 C -3.07638200 2.68508200 1.31506300 H -3.05428800 2.74790700 2.40949700 C -0.79003100 -1.80335800 1.78763500 C -1.69799600 0.33334200 2.67932100 O -2.17403600 1.09488600 3.52004500 N -1.85286700 0.48378500 1.30128200 C -2.48457000 1.56877800 0.69278600 C -2.52841800 1.49081700 -0.74216500 C -3.15947900 2.51322200 -1.52846000 C -3.13612500 2.34486700 -2.94285400 C -2.51714000 1.22974700 -3.49656800 C -1.91632000 0.27163100 -2.64260100 N -1.92630200 0.39469800 -1.31265000 H -4.24701900 4.41063200 -1.44832900 I -0.77207600 -2.83307400 -1.34345500 C -0.86438100 -0.91399100 3.02882500 C 0.52679800 -0.43163100 3.50736100 H 0.41570000 0.23117900 4.38951300 H 1.15266300 -1.30093900 3.79956600 H 1.06326000 0.12834900 2.71683000 C -1.56845000 -1.66280900 4.18590800 H -0.95977600 -2.52740900 4.52235300 H -1.71170800 -0.96835400 5.03939200 H -2.56760600 -2.03757800 3.88109300 H -1.69090200 -2.44965200 1.68623200 H 0.11761300 -2.43255100 1.73078500 C 0.72688200 -0.15427200 0.05878300 C 1.85460800 -0.99583900 0.12837500 C 0.88977800 1.23451800 -0.10546700 C 3.14251500 -0.44475500 0.01933400 H 1.74613600 -2.08218200 0.24818000 C 2.18241600 1.77539300 -0.21159700 H 0.03009000 1.91893200 -0.14677600 C 3.31942400 0.94448100 -0.15186400 H 4.02194700 -1.10440700 0.06036200 H 2.32666000 2.86000800 -0.33714800 C 4.66570600 1.58595500 -0.27333700 O 4.85145700 2.78404300 -0.42758700 O 5.67703900 0.67968800 -0.19246000

52

C 7.01556500 1.21792300 -0.30234300 H 7.16345800 1.97674500 0.49636900 H 7.10742900 1.75510300 -1.27119500 C 7.99715500 0.06480200 -0.18899300 H 7.83735100 -0.67819900 -0.99672400 H 9.03641100 0.44385100 -0.26964600 H 7.89422900 -0.45455000 0.78553900 47 Ni (IV) CF3 xyz H 3.28424300 -3.22549800 -3.50181800 H 2.21142000 -1.18935300 -4.54787000 H 1.18051600 0.56999500 -3.04355800 Ni 0.82908900 0.79773800 0.13495900 C 3.40562400 -3.69054800 -0.76370200 C 3.34439100 -3.72895900 0.62614600 H 3.77996300 -4.58510300 1.16558400 C 2.73648700 -2.69572400 1.38631000 H 2.70753400 -2.73636500 2.48165500 C 0.55610500 1.85534600 1.75764100 C 1.40834500 -0.28457200 2.69641400 O 1.85921600 -1.04223500 3.55408300 N 1.56822300 -0.46525500 1.32218400 C 2.17549600 -1.57775600 0.73882300 C 2.22834000 -1.52935800 -0.69713700 C 2.83895600 -2.58172100 -1.45961800 C 2.82773500 -2.44050500 -2.87715200 C 2.23865300 -1.32197600 -3.45616500 C 1.65589300 -0.33347000 -2.62463400 N 1.65545700 -0.43066900 -1.29236700 H 3.88057200 -4.50246900 -1.33596800 I 0.56952700 2.81962500 -1.39359600 C 0.60576100 0.99042400 3.01705500 C -0.79807500 0.55435400 3.50299000 H -0.70543200 -0.09301400 4.39858200 H -1.40134500 1.44534500 3.77662900 H -1.34827800 -0.00758800 2.72333700 C 1.32689800 1.74584600 4.15953900 H 0.74034400 2.63320900 4.47523100 H 1.44975900 1.06680800 5.02844500 H 2.33622300 2.08743400 3.84937400 H 1.47177900 2.47870800 1.64564900 H -0.33666300 2.50388000 1.68429800 C -0.98970600 0.20741800 0.05563300 C -2.09953300 1.07300400 0.10057000 C -1.18602500 -1.17937500 -0.07477500 C -3.39931300 0.54824100 -0.00242400 H -1.97012000 2.15906500 0.20008700 C -2.49083400 -1.69721700 -0.17425600 H -0.34319000 -1.88544100 -0.09191600 C -3.60227600 -0.83707200 -0.14195700

53

H -4.26151300 1.23210300 0.02766500 H -2.63640100 -2.78460400 -0.26425100 C -4.99990400 -1.38926700 -0.30830100 F -5.37888400 -1.40892600 -1.61503800 F -5.09849000 -2.66407300 0.14835300 F -5.92000500 -0.64446800 0.35592700 98 5 dimer [Ni(Opiv)(AQPiv)]2, pentet state Ni 1.40270700 -0.32266000 0.47266800 N 0.03678500 -1.37214500 -0.77309300 N 1.99774400 -2.20136100 0.91209100 O -0.32402400 0.26331200 -2.23663500 O 2.82156900 0.29780600 -0.95433900 O 3.10248700 0.70709500 1.19629000 C 0.15640100 -0.89272500 -2.05199600 C 0.85151400 -1.59545400 -3.24151100 C 1.49969200 -0.48436500 -4.10514000 C -0.23025500 -2.32414600 -4.08201200 C 1.95165400 -2.58239600 -2.79715500 C 0.04927500 -2.72067600 -0.38987000 C -0.92237100 -3.65597600 -0.77110600 C -0.86081800 -4.99709500 -0.30920100 C 0.15071900 -5.42597600 0.54586900 C 1.14432800 -4.50166700 0.98644400 C 1.07984100 -3.14247100 0.52287200 C 2.21617500 -4.83410500 1.86820500 C 3.13369600 -3.85937900 2.24077800 C 2.98354700 -2.53833700 1.74413600 C 3.52577600 0.79167400 -0.00863000 C 4.87132200 1.46844800 -0.33387400 C 4.60614000 2.60714800 -1.34755400 C 5.79045000 0.40420200 -0.98252800 C 5.52218300 2.02718200 0.94471100 Ni -1.40271900 0.32266500 -0.47266100 N -0.03678300 1.37213800 0.77309500 N -1.99773800 2.20137000 -0.91208900 O 0.32400500 -0.26331600 2.23664300 O -2.82158400 -0.29779800 0.95434100 O -3.10248500 -0.70710100 -1.19628700 C -0.15641200 0.89272300 2.05199900 C -0.85152900 1.59546000 3.24150900 C -1.49970700 0.48437600 4.10514400 C 0.23023900 2.32415700 4.08200600 C -1.95166800 2.58239800 2.79714400 C -0.04926300 2.72067100 0.38986900 C 0.92239100 3.65596200 0.77110300 C 0.86084800 4.99708200 0.30919700 C -0.15068800 5.42597100 -0.54587100 C -1.14430500 4.50166900 -0.98644400 C -1.07982700 3.14247300 -0.52287200

54

C -2.21615100 4.83411600 -1.86820300 C -3.13367900 3.85939600 -2.24077500 C -2.98353900 2.53835400 -1.74413200 C -3.52577900 -0.79168200 0.00863100 C -4.87132400 -1.46846000 0.33386900 C -4.60615000 -2.60714100 1.34757400 C -5.79046700 -0.40420700 0.98249100 C -5.52216400 -2.02722100 -0.94471500 H 6.49633100 2.50252100 0.70198200 H 4.87692500 2.78833300 1.42791400 H 5.70129300 1.22697000 1.69055500 H 5.99845800 -0.43108400 -0.28090000 H 6.76328900 0.85885600 -1.26674200 H 5.32181600 -0.01987600 -1.89277800 H 4.12014500 2.21585100 -2.26308400 H 3.94158600 3.38434400 -0.91574200 H 5.56177700 3.09487700 -1.63553300 H 2.66679600 -2.08908400 -2.10881700 H 2.51486400 -2.92555800 -3.69048400 H 1.54311400 -3.48457000 -2.30207400 H 1.99325600 -0.94361900 -4.98723600 H 0.74232700 0.24146500 -4.45756100 H 2.25829400 0.06735500 -3.51506100 H -0.67521700 -3.17813200 -3.53318100 H 0.22970200 -2.72150100 -5.01179300 H -1.04640600 -1.63046200 -4.36952700 H -3.66771200 1.72429300 -2.03562400 H -3.96696900 4.08975500 -2.92152500 H -2.30188200 5.86514300 -2.24829400 H -0.19083100 6.46880700 -0.89762100 H 1.63724000 5.70775100 0.63483500 H 1.74485600 3.32478500 1.42251200 H 3.66771300 -1.72427100 2.03562800 H 3.96698600 -4.08973200 2.92153000 H 2.30191400 -5.86513200 2.24829600 H 0.19087000 -6.46881300 0.89762000 H -1.63720400 -5.70776900 -0.63484200 H -1.74483600 -3.32480400 -1.42251600 H -3.94158500 -3.38434000 0.91578600 H -4.12017100 -2.21582400 2.26310300 H -5.56178900 -3.09487000 1.63554700 H -6.76330700 -0.85886200 1.26670200 H -5.32184800 0.01989100 1.89273900 H -5.99847000 0.43106400 0.28084500 H -6.49631500 -2.50255600 -0.70199100 H -5.70126300 -1.22702300 -1.69057700 H -4.87689800 -2.78838000 -1.42789300 H 1.04639000 1.63047600 4.36952700 H 0.67520200 3.17814000 3.53317000 H -0.22971900 2.72151800 5.01178400 H -2.51487900 2.92556600 3.69047100

55

H -1.54312800 3.48456900 2.30205900 H -2.66680900 2.08908100 2.10880800 H -0.74234200 -0.24144900 4.45757400 H -1.99327600 0.94363600 4.98723400 H -2.25830500 -0.06735100 3.51506600 108 Dimer 5 1DMSO pentet Ni 1.68787900 -0.70488000 -0.14721600 N 1.92068000 1.22643700 0.47192600 N 3.65811700 -0.50350600 -0.54441800 O -0.10226300 1.28041500 1.47877300 O 1.64501700 -1.85615200 1.63501400 O 1.70441200 -2.81332600 -0.35406200 C 1.09786100 1.69636200 1.42340400 C 1.52705700 2.63123900 2.60734600 C 0.90637000 2.03936300 3.89920900 C 0.90523300 4.03130900 2.37872500 C 3.05068200 2.72732500 2.83622800 C 3.04935500 1.77237600 -0.09904700 C 3.31549300 3.13467200 -0.33942100 C 4.52628900 3.54979400 -0.94704200 C 5.49627700 2.63740900 -1.35735700 C 5.24222400 1.24155700 -1.21705100 C 4.00574900 0.81763900 -0.61816500 C 6.12626200 0.21307300 -1.66194700 C 5.75695400 -1.12175700 -1.54392500 C 4.48813900 -1.44407200 -0.99733500 C 1.67736000 -2.91646800 0.91880300 C 1.64672300 -4.31527200 1.56984900 C 2.14675200 -4.24781000 3.02594200 C 2.52574400 -5.28320800 0.74889800 C 0.17240700 -4.79414700 1.53039700 Ni -1.54774800 0.53905900 0.20866200 N -0.73618300 -0.84321300 -1.22416500 N -3.29057100 -0.35597600 -0.44928900 O 1.25087300 -0.07960000 -1.99643200 O -1.55663300 2.25209200 -0.99991900 O -2.72805800 2.23406100 0.87728300 C 0.05259100 -0.41041100 -2.24518200 C -0.41276000 -0.16520400 -3.71114800 C 0.04783800 1.27908300 -4.05490500 C 0.31208100 -1.16663400 -4.64368300 C -1.93855300 -0.23887300 -3.91562000 C -1.68887300 -1.84022800 -1.41791000 C -1.39977800 -3.10335600 -1.96222600 C -2.42135200 -4.07156800 -2.13956400 C -3.74165200 -3.81722600 -1.77428800 C -4.07963300 -2.55946200 -1.19183500 C -3.04208100 -1.58197100 -0.99812000 C -5.39658700 -2.18636400 -0.79020600

56

C -5.62280000 -0.92745100 -0.24556300 C -4.53095400 -0.03578000 -0.07861700 C -2.34310800 2.83808000 -0.17989700 C -2.84614100 4.26198200 -0.50511000 C -1.63631700 5.14445300 -0.88626200 C -3.80149800 4.14556500 -1.71935900 C -3.59179600 4.86241700 0.70087700 H 0.07916200 -5.79079000 2.01283200 H -0.49528700 -4.08446500 2.06050700 H -0.19122100 -4.87490400 0.48621100 H 2.20761100 -5.30015700 -0.31167100 H 2.45346000 -6.31284000 1.15944200 H 3.59400800 -4.98115900 0.77943400 H 3.19126700 -3.87701100 3.07776100 H 1.52322300 -3.56704500 3.63743000 H 2.11688000 -5.25718800 3.48901700 H 3.51484800 1.72049100 2.88083900 H 3.24113000 3.22913700 3.80854500 H 3.57816500 3.30708100 2.05731600 H 1.13018900 2.70693100 4.75788800 H -0.19015000 1.93443000 3.80154900 H 1.33831500 1.04151100 4.12416500 H 1.32738600 4.53898000 1.48732300 H 1.09867000 4.68284300 3.25761600 H -0.19176700 3.94655100 2.24121700 H -4.64943200 0.96011000 0.37965000 H -6.63108700 -0.61284100 0.06454000 H -6.22410200 -2.90318500 -0.92009300 H -4.52833200 -4.57377000 -1.92205800 H -2.15642300 -5.04893600 -2.57470600 H -0.35656000 -3.33553300 -2.22279300 H 4.11571000 -2.48029000 -0.94707500 H 6.41780200 -1.93013800 -1.89173800 H 7.09184700 0.49278600 -2.11420300 H 6.43748500 2.97478700 -1.81838700 H 4.69619400 4.62813200 -1.09836400 H 2.56330700 3.88531300 -0.05883200 H -0.93580000 5.25492300 -0.03241400 H -1.07524800 4.69957200 -1.73146400 H -1.97668500 6.16005300 -1.18133600 H -4.17877400 5.14924700 -2.01063800 H -3.28007300 3.70125700 -2.59077900 H -4.67974000 3.50860900 -1.48211000 H -3.96691000 5.87859500 0.45381800 H -4.45529300 4.23324400 0.99544100 H -2.92773600 4.94497000 1.58537900 H 1.40880600 -1.12683000 -4.48632400 H -0.02848800 -2.20808200 -4.46905100 H 0.10378300 -0.91438200 -5.70552400 H -2.18608800 0.13352400 -4.93230700 H -2.33537800 -1.26927200 -3.83786000

57

H -2.46749000 0.40109700 -3.18138500 H 1.14490900 1.38011500 -3.95236600 H -0.24036600 1.52028600 -5.09997800 H -0.43279900 2.00987500 -3.37298100 S -1.75400100 -0.34662000 3.20852100 O -1.84876400 -0.87984200 1.74975000 C -3.28454700 -0.98471700 3.99434500 H -4.12289500 -0.41133600 3.55525500 H -3.38663800 -2.06142700 3.75474100 H -3.23745900 -0.81351900 5.08879900 C -0.55327300 -1.45726300 4.02527400 H -0.34453400 -1.08150900 5.04700900 H -0.95839600 -2.48782400 4.04937700 H 0.35394400 -1.42521300 3.38380000 118 Dimer5 2 DMSO, pentet state Ni 3.58285700 -0.53449800 -0.36275800 N 4.29382600 0.74075600 0.95517800 N 4.55310100 0.64555900 -1.66652000 O 3.02374700 0.83365200 2.87597800 O 3.19694700 -2.30155200 0.76940000 O 3.65305000 -2.36435000 -1.39175400 C 4.11127700 0.60442300 2.34296100 C 5.27411300 0.00772000 3.19601000 C 4.75429300 -1.36149700 3.71073200 C 5.52241600 0.94203000 4.40366700 C 6.57396400 -0.20354200 2.39806800 C 4.95842600 1.79036800 0.38814500 C 5.48386500 2.93350700 1.03726600 C 6.15736000 3.94054300 0.30505700 C 6.32975600 3.87311100 -1.07856200 C 5.79697300 2.75719300 -1.78957100 C 5.10689600 1.73406100 -1.05507100 C 5.89597600 2.56758500 -3.20057600 C 5.33990100 1.43877600 -3.79629900 C 4.66329200 0.49004800 -2.98999600 C 3.40696800 -2.97783300 -0.29503300 C 3.43083600 -4.51845700 -0.24332100 C 2.34360800 -5.02434900 0.72783900 C 4.83210500 -4.91785000 0.29023800 C 3.22322400 -5.10656700 -1.65231400 Ni -3.35798500 0.62220900 -0.03082100 N -4.42502700 -1.01835800 -0.37696300 N -4.41528600 0.59827900 1.68843400 O -3.12687600 -0.55383000 -2.09731900 O -4.49347300 2.11481300 -1.00674400 O -2.58790300 2.61034800 -0.00220000 C -4.07069500 -1.27887500 -1.65824200 C -4.72672400 -2.31025800 -2.61108600 C -4.14269200 -2.13160300 -4.02919400

58

C -4.40140200 -3.74642900 -2.12941900 C -6.25247200 -2.05480900 -2.68127200 C -5.27970700 -1.39989700 0.62344300 C -6.13006400 -2.52164500 0.74009600 C -6.93482900 -2.72870400 1.88815100 C -6.93547200 -1.84437700 2.96199100 C -6.08990700 -0.69749500 2.91804300 C -5.26001300 -0.48195100 1.76259300 C -6.01241800 0.26710400 3.96770400 C -5.15922400 1.35717000 3.85164800 C -4.36517600 1.48537300 2.68512300 C -3.61632600 2.97625700 -0.67943700 C -3.80615600 4.44655800 -1.10488200 C -3.89114700 4.48226900 -2.65007600 C -5.14369700 4.94358500 -0.50502800 C -2.63803500 5.31858200 -0.61102300 H 3.29725600 -6.21425700 -1.62193400 H 2.22346400 -4.84530100 -2.05837400 H 3.98094800 -4.71970100 -2.36137900 H 5.63522200 -4.54843700 -0.38071500 H 4.91669700 -6.02380500 0.35080400 H 5.00669400 -4.50143900 1.30311400 H 2.46798400 -4.57099400 1.73057200 H 1.32528600 -4.76851100 0.36571600 H 2.39834600 -6.12912100 0.82737200 H 6.40997900 -0.87595300 1.53222300 H 7.34469100 -0.66648600 3.05021600 H 6.98914500 0.75061700 2.01427000 H 5.53937900 -1.85966700 4.31857500 H 3.85548700 -1.22045900 4.34385200 H 4.47532000 -2.02520300 2.86677300 H 5.96598200 1.91094900 4.09063800 H 6.22741800 0.46648700 5.11803000 H 4.57117200 1.15014500 4.93296500 H -3.66803300 2.32829000 2.54661500 H -5.08542200 2.11479200 4.64648100 H -6.63805800 0.13298400 4.86522700 H -7.57296600 -2.01541500 3.84316500 H -7.57996100 -3.62179500 1.91894800 H -6.17755400 -3.26124800 -0.06775800 H 4.20458100 -0.41781700 -3.41544700 H 5.41376600 1.27340300 -4.88189200 H 6.41881100 3.32311900 -3.80962900 H 6.86254300 4.66536900 -1.62621500 H 6.55496100 4.80897300 0.85534500 H 5.35611200 3.04522200 2.12449900 H -2.94340100 4.13496800 -3.11294100 H -4.70847100 3.82700400 -3.01129200 H -4.08297900 5.51816300 -3.00276500 H -5.35007400 5.98544700 -0.83084800 H -5.98238300 4.29713800 -0.83158800

59

H -5.11564700 4.93428600 0.60515600 H -2.78659100 6.37390200 -0.92474900 H -2.55521700 5.29487400 0.49444100 H -1.67039500 4.96772400 -1.02316900 H -3.30854100 -3.93580600 -2.17592000 H -4.72116600 -3.94158800 -1.08753200 H -4.90084600 -4.49242100 -2.78387800 H -6.73170900 -2.79593200 -3.35595100 H -6.75194600 -2.12227000 -1.69606200 H -6.45676900 -1.04289400 -3.08773800 H -3.04926800 -2.31049800 -4.04412900 H -4.62153700 -2.85194700 -4.72622400 H -4.31611300 -1.10573700 -4.40949200 O 1.68767200 -0.19013400 -0.93362400 S 1.01660200 -0.73346500 -2.25325300 C -0.13675300 -2.02475500 -1.68396000 C -0.19578100 0.56795200 -2.64749700 H -0.79745500 -2.30315200 -2.52805500 H 0.49101200 -2.88156800 -1.37530800 H -0.72089300 -1.59757200 -0.84034600 H -0.83175700 0.22384400 -3.48594100 H -0.82149800 0.74829800 -1.75274400 H 0.39160400 1.46183400 -2.93035500 O -1.59153900 -0.23184200 0.57130600 S -0.86817800 0.38760700 1.83436300 C 0.23303200 1.69099200 1.19901200 C 0.36931300 -0.87150800 2.26750600 H 0.92743800 1.98322900 2.01164200 H 0.79997400 1.25626500 0.35135500 H -0.43979300 2.50950200 0.87913500 H 0.96028400 -1.12379100 1.36572000 H 1.04066000 -0.44811300 3.04066900 H -0.18969500 -1.74743900 2.64743300 49 Mono5 triplet Ni 0.32590800 0.13689800 0.19986700 N -1.40920000 0.96123000 0.02638300 N -0.66844900 -1.56778200 0.23318200 O -2.77633700 2.83609500 -0.11482100 O 1.93482200 -0.16049600 -1.04059800 O 2.09870100 -0.42856500 1.13105900 C -1.65408800 2.33329800 -0.00233500 C -0.39193500 3.24611100 0.09760500 C -0.86406200 4.70798800 0.22221000 C 0.45056900 3.08337800 -1.19138900 C 0.45839900 2.88559800 1.33590500 C -2.43639500 0.01961400 -0.09396500 C -3.81243800 0.24156200 -0.30514000 C -4.71819900 -0.84768700 -0.40202700 C -4.30973800 -2.17243300 -0.28672400 C -2.92981900 -2.45474200 -0.06601400

60

C -2.00669600 -1.35640600 0.02004000 C -2.39284000 -3.76607300 0.08727700 C -1.03229000 -3.94320700 0.31831300 C -0.19159200 -2.80551600 0.38497400 C 2.65969600 -0.43934600 -0.01953200 C 4.14901900 -0.76230500 -0.19443900 C 4.83422500 0.50793600 -0.75965300 C 4.27534000 -1.91643100 -1.21806800 C 4.77565300 -1.15753800 1.15515900 H 5.85608100 -1.37669000 1.02365900 H 4.67233800 -0.34477100 1.90139400 H 4.28897200 -2.05911300 1.57930200 H 3.80251900 -2.84681800 -0.83865900 H 5.34564900 -2.13698900 -1.41434700 H 3.78787500 -1.64919300 -2.17656100 H 4.37230200 0.81298000 -1.71978800 H 4.75386800 1.35796100 -0.05028900 H 5.91287300 0.31129000 -0.93474500 H -0.13740600 2.92780900 2.27097000 H 1.31242500 3.58878400 1.43681500 H 0.91205600 1.86416800 1.28550600 H 0.01106800 5.38947900 0.26942300 H -1.49341700 4.99667600 -0.64187300 H -1.47577500 4.85720200 1.13464400 H 0.85694000 2.05477600 -1.30108600 H 1.31509000 3.78124200 -1.17534800 H -0.15273500 3.30857000 -2.09512800 H 0.89045400 -2.89418700 0.57354300 H -0.59903200 -4.94603500 0.44869700 H -3.06972100 -4.63380100 0.02602200 H -5.02953500 -3.00276400 -0.35631800 H -5.78377300 -0.62254300 -0.57051200 H -4.16532300 1.27561500 -0.38686600 59 Monomer 5 DMSO triplet Ni 0.24603800 0.23952100 0.16644300 N -1.54444300 1.03435900 -0.24319600 N -0.56673000 -1.45205100 -0.49010700 O -3.06030300 2.79711200 -0.29547200 O 1.54101800 0.63872500 -1.47075100 O 2.27001300 -0.45714400 0.30326800 C -1.91259300 2.35890600 -0.11781800 C -0.76783700 3.38141300 0.18236500 C -1.37816000 4.57658300 0.94350800 C -0.23025400 3.85254100 -1.19389700 C 0.38684300 2.79755700 1.01374200 C -2.44290600 0.05486100 -0.64411000 C -3.81881200 0.20180400 -0.94469100 C -4.59946700 -0.89976900 -1.37028100 C -4.07322800 -2.18135800 -1.51956100

61

C -2.69727700 -2.39543800 -1.22908500 C -1.89332400 -1.28147600 -0.78712200 C -2.04660100 -3.65901900 -1.35086200 C -0.69575000 -3.78777100 -1.04925200 C 0.01942400 -2.64546000 -0.61240200 C 2.48268000 0.03005100 -0.86726000 C 3.85406200 -0.11493600 -1.55495300 C 4.36954300 1.30509600 -1.89243200 C 3.63759400 -0.90983100 -2.86633500 C 4.85431800 -0.84654400 -0.64186300 H 5.83281800 -0.95528600 -1.15587400 H 5.02278400 -0.28915500 0.30208300 H 4.49124200 -1.85892900 -0.37225200 H 3.26953100 -1.93706300 -2.66024000 H 4.59351900 -0.99672300 -3.42512600 H 2.89417300 -0.40295300 -3.51290200 H 3.64105400 1.84584700 -2.52822500 H 4.53353300 1.90394400 -0.97178100 H 5.33658000 1.24394000 -2.43521200 H 0.04330500 2.32215700 1.95299900 H 1.11579900 3.59539900 1.27707900 H 1.00081300 2.07127500 0.42028700 H -0.62952600 5.38917000 1.05763600 H -2.25901900 4.96642900 0.39876100 H -1.71942400 4.27633200 1.95690900 H 0.22479000 3.00817100 -1.75125600 H 0.54494500 4.63846800 -1.06045500 H -1.05128800 4.27823700 -1.80630700 H 1.09019400 -2.68787000 -0.35341000 H -0.17604100 -4.75338600 -1.14231000 H -2.63186600 -4.52932600 -1.69088100 H -4.69585800 -3.02452000 -1.85736600 H -5.66508500 -0.72437200 -1.59278900 H -4.25789200 1.20042800 -0.84221200 O -0.12836600 -0.09284900 2.18304900 S 0.49944000 -1.39374200 2.77426000 C 2.13886100 -0.89729200 3.41744700 C -0.39247000 -1.58528000 4.35744200 H 2.58966900 -1.74576200 3.97059000 H 2.72420600 -0.66339600 2.50583500 H 2.01815500 -0.00419300 4.06145300 H 0.04683400 -2.42501200 4.93216100 H -0.33254800 -0.63111200 4.91661900 H -1.44406000 -1.80816600 4.09451600 69 Monomer 5 2 DMSO trans position, most stable form Ni -0.49418900 -0.16470900 -0.04205600 N 1.17200200 0.79158900 0.84886100 N 0.94837400 -1.27726000 -0.87125800 O 1.95615900 2.97189400 0.85169800

62

O -2.44885500 0.56236200 0.40108500 O -2.11956800 -1.05691400 -1.06762300 C 1.15326000 2.11230600 1.26966900 C 0.06769000 2.56737500 2.28943700 C 0.75102400 3.55541700 3.26639600 C -0.55112800 1.41094300 3.09437400 C -1.03254900 3.32369200 1.50035300 C 2.34062800 0.27642600 0.31159900 C 3.66383700 0.70888900 0.58217000 C 4.78647500 0.02052600 0.06972100 C 4.66933700 -1.10386300 -0.75088600 C 3.36982200 -1.57208500 -1.08636400 C 2.21833400 -0.88201400 -0.55444800 C 3.11296400 -2.68922400 -1.93882200 C 1.80627300 -3.05701300 -2.24223700 C 0.73272500 -2.31270100 -1.68736600 C -2.91346000 -0.28610600 -0.42925600 C -4.44013100 -0.38102600 -0.63536700 C -4.96137400 1.01733100 -1.04028600 C -5.06462800 -0.79469600 0.71931000 C -4.77866300 -1.41833400 -1.72107500 H -5.87898800 -1.48799400 -1.85992800 H -4.32209200 -1.14510000 -2.69413400 H -4.39635500 -2.42269500 -1.44878400 H -4.69448800 -1.79047500 1.04212600 H -6.17158400 -0.84827400 0.63723300 H -4.80128400 -0.06268000 1.50851000 H -4.68912200 1.77141500 -0.27551300 H -4.52638600 1.34239500 -2.00890100 H -6.06724800 1.00359200 -1.14888100 H -0.58196500 4.15106200 0.91387800 H -1.76800600 3.76422500 2.20796700 H -1.57622600 2.64481500 0.81538900 H 0.00019600 3.97369400 3.96977900 H 1.53785800 3.05211500 3.86884900 H 1.22982300 4.38567700 2.71263400 H -1.05562800 0.66733600 2.45049800 H -1.30595700 1.81229700 3.80457400 H 0.22310900 0.89204300 3.70157200 H -0.32579600 -2.54174200 -1.89785000 H 1.59237300 -3.90884200 -2.90593600 H 3.96598600 -3.24687100 -2.35980900 H 5.55706100 -1.61974100 -1.14872600 H 5.79032100 0.39644800 0.32842600 H 3.81210900 1.60422100 1.19873800 O -0.49636500 1.35123500 -1.50095400 S 0.69706200 1.52642900 -2.48580200 C -0.12579700 1.76142600 -4.10624700 C 1.30223200 3.22860500 -2.22611700 H 0.62925800 2.00590600 -4.88008900 H -0.62271900 0.80081300 -4.34026400

63

H -0.88044100 2.56588600 -4.00401400 H 2.08692100 3.44563300 -2.97893000 H 0.44829900 3.92931600 -2.30977500 H 1.72615900 3.24142800 -1.19549100 O -0.95962300 -1.56628300 1.48734100 S -0.32626600 -2.51664800 2.52342600 C 0.01703100 -4.09422200 1.63380300 C 1.41967100 -2.01342400 2.79635400 H 0.51145500 -4.80467700 2.32675400 H -0.96917500 -4.48790800 1.32199500 H 0.64585200 -3.88721800 0.74614700 H 1.99596700 -2.07824000 1.85409700 H 1.38105400 -0.96209400 3.13698200 H 1.84612600 -2.66842600 3.58260300 86 6 dimer DMSO Ni -0.82347000 0.04392500 -0.94615800 O -1.26348000 1.97132000 -0.44225800 O -0.05729100 1.86815300 1.45505300 O -2.29355500 -0.59546500 0.38981400 O -0.75246400 -0.83290800 2.02588400 C -0.81973500 2.47800000 0.63551400 C -1.93199800 -0.93083800 1.57082100 C -1.23856200 3.93289500 0.96687300 C -0.75589900 4.83668400 -0.19285700 C -0.61672400 4.39204200 2.29826400 C -2.78201300 3.98274900 1.05313400 C -2.99229300 -1.50782800 2.54939700 C -4.38745300 -1.57769600 1.90457700 C -3.02979300 -0.59197700 3.79635100 C -2.52731300 -2.92493500 2.96293800 Ni 0.69678000 0.09131400 0.96931700 O 1.29222800 -1.69962500 0.16911000 O -0.39078100 -1.88582200 -1.31392800 O 2.10156400 1.02002400 -0.21159300 O 0.79365800 0.64708200 -2.01586900 C 0.63666200 -2.33890300 -0.71550600 C 1.86747300 1.03773400 -1.47101800 C 1.14418500 -3.75889500 -1.07442900 C 1.15659600 -4.60669900 0.21913300 C 0.23991300 -4.41298600 -2.13440800 C 2.58646500 -3.61815300 -1.61797000 C 2.99319700 1.58501600 -2.39060500 C 4.25020200 0.70637300 -2.19101000 C 2.55333100 1.54907600 -3.86583200 C 3.29989600 3.04088100 -1.96694100 H 5.09411000 1.09259100 -2.80184600 H 4.56309900 0.69487900 -1.12776800 H 4.05866700 -0.34300700 -2.49811500 H 2.40670800 3.68902300 -2.08639100

64

H 3.61909700 3.09257600 -0.90670200 H 4.11256200 3.46236800 -2.59657800 H 2.31174000 0.51675300 -4.18781400 H 3.36476700 1.94030500 -4.51633700 H 1.64503500 2.16230200 -4.02860600 H -3.23889700 3.64189300 0.10293200 H -3.16113400 3.33444200 1.87100900 H -3.12374600 5.02033700 1.25521800 H 0.49022500 4.35291600 2.25882200 H -0.92193100 5.43645700 2.52275800 H -0.93909900 3.74494500 3.13841800 H -1.17530300 4.49275400 -1.15914100 H 0.35117900 4.82375900 -0.27562500 H -1.07236300 5.88764800 -0.02044400 H -2.02501000 -0.51849400 4.25653000 H -3.36041800 0.43438400 3.53122300 H -3.73972000 -0.99487800 4.55004900 H -3.22812600 -3.35963000 3.70743700 H -1.51383400 -2.88711000 3.40840200 H -2.49371400 -3.60828000 2.08803700 H -4.38949300 -2.22726900 1.00567400 H -5.12065800 -1.99464900 2.62752000 H -4.74518000 -0.57362500 1.59813400 H 0.62126100 -5.42432600 -2.39141600 H -0.80008300 -4.51892400 -1.76510100 H 0.20457800 -3.80663800 -3.06150900 H 1.56478900 -5.61956500 0.01459500 H 1.77828800 -4.12289900 0.99822200 H 0.13257300 -4.72808900 0.63038600 H 3.01084200 -4.61806900 -1.85136400 H 2.60595000 -3.01357900 -2.54893500 H 3.23926800 -3.12134400 -0.87291700 O -1.98639900 0.31247100 -2.62163200 S -3.47219500 -0.06533600 -2.85261600 C -3.67069300 -1.78679700 -2.25352400 C -4.42523500 0.79092900 -1.54163600 H -4.73474100 -2.08104400 -2.35380900 H -3.03027000 -2.40843900 -2.90688900 H -3.31328000 -1.82564200 -1.20555700 H -5.49236100 0.50254600 -1.62417800 H -3.98079300 0.50957600 -0.56619100 H -4.29861700 1.87216900 -1.73732600 O 2.15658900 -0.26245700 2.37019800 S 3.60033400 -0.42817100 1.81210000 C 4.37290100 1.21231800 2.06383700 C 4.43923800 -1.34196800 3.15822700 H 5.45085700 1.16472800 1.80958600 H 3.82963000 1.86711900 1.35620100 H 4.20866600 1.53230000 3.11121500 H 5.52332300 -1.41415500 2.93840700 H 4.25031800 -0.82378700 4.11862400

65

H 3.98371900 -2.35025700 3.17274900 110 Dimer 5 1 DMF Ni -1.72954900 0.47054000 -0.18755000 N -1.77300500 -1.51716800 0.34673500 N -3.70240900 0.13113500 -0.47531100 O 0.38442700 -1.69075500 1.04370000 O -1.75996300 1.58726500 1.62204500 O -1.99089300 2.57104100 -0.34152200 C -0.82237900 -2.05963000 1.13465200 C -1.10816800 -3.04054200 2.33054800 C -0.32375000 -2.47728800 3.54570800 C -0.52787800 -4.43797000 2.00247600 C -2.59226800 -3.13474000 2.74297900 C -2.91292900 -2.10820000 -0.15018700 C -3.11399800 -3.47869400 -0.41764700 C -4.34357100 -3.95757000 -0.93136200 C -5.40250300 -3.10160700 -1.22777100 C -5.22402500 -1.69695500 -1.06561700 C -3.97023600 -1.20682800 -0.55784000 C -6.20559300 -0.71872100 -1.40669500 C -5.91265500 0.63406300 -1.28241100 C -4.62592200 1.02564300 -0.83235200 C -1.94092700 2.64789700 0.93450700 C -2.06331400 4.02338700 1.62587500 C -2.67090100 3.85867000 3.03357200 C -2.94072900 4.96316900 0.77332900 C -0.62925600 4.60408500 1.72810000 Ni 1.64136300 -0.40840700 0.06153000 N 0.55353100 0.89298300 -1.23582000 N 3.12112600 0.96448400 -0.33078500 O -1.29705200 -0.08927100 -2.08775000 O 2.24120500 -1.92719800 -1.25685800 O 3.17422200 -1.78610000 0.74373700 C -0.14635100 0.38727800 -2.29994200 C 0.40306700 0.23618300 -3.74566900 C 0.24442000 -1.27268600 -4.08731300 C -0.47721000 1.07221500 -4.70682100 C 1.88916500 0.61161300 -3.90192200 C 1.27443900 2.07895200 -1.36378600 C 0.74453300 3.25898200 -1.91676000 C 1.52753200 4.43645000 -2.01379900 C 2.84349000 4.48030200 -1.55724500 C 3.42003200 3.31622500 -0.96992300 C 2.62428100 2.12091400 -0.86413100 C 4.75932500 3.24365300 -0.48409400 C 5.23930300 2.05253700 0.04664900 C 4.38011800 0.92483600 0.11074200 C 3.05331400 -2.38096500 -0.38135300 C 3.88409800 -3.64054600 -0.70562100

66

C 2.90540500 -4.78340400 -1.06543900 C 4.77439800 -3.31911100 -1.93060600 C 4.75482200 -4.04176900 0.49904200 H -0.65231500 5.59531600 2.23007000 H 0.03461600 3.93389900 2.31063900 H -0.17893000 4.73309600 0.72276900 H -2.54037600 5.05483000 -0.25498300 H -2.98007900 5.97440800 1.23152900 H -3.98220900 4.58525100 0.69840000 H -3.69671400 3.43786000 2.98322900 H -2.06323900 3.17431600 3.65683300 H -2.72922100 4.84300200 3.54543200 H -3.03304800 -2.12680700 2.88606900 H -2.66915900 -3.67830100 3.70856100 H -3.21723700 -3.67547400 2.00892900 H -0.47236600 -3.14100500 4.42363400 H 0.75713400 -2.41718800 3.31933500 H -0.68239900 -1.46237000 3.81531200 H -1.07493800 -4.94267600 1.18052000 H -0.59090100 -5.09556300 2.89581400 H 0.53774300 -4.35451900 1.70757000 H 4.70742400 -0.03882600 0.53422200 H 6.27135900 1.96808900 0.41973000 H 5.40260300 4.13709000 -0.54133500 H 3.44429400 5.39968400 -1.63840400 H 1.07481400 5.33867400 -2.45611200 H -0.30750200 3.26288800 -2.23595200 H -4.31581700 2.08198800 -0.78367200 H -6.64962800 1.40560700 -1.55229200 H -7.18591900 -1.05110100 -1.78574400 H -6.35675000 -3.48732400 -1.61865400 H -4.45540600 -5.04047900 -1.10341900 H -2.29437100 -4.18660500 -0.23167300 H 2.25105200 -5.03777900 -0.20550300 H 2.25543500 -4.49277800 -1.91426500 H 3.46882700 -5.69832200 -1.34778300 H 5.36644300 -4.21281600 -2.22222500 H 4.15577200 -3.00931500 -2.79620600 H 5.48767200 -2.49772100 -1.70691500 H 5.34254800 -4.95387100 0.26083900 H 5.46464800 -3.23494800 0.77238700 H 4.13309000 -4.25165300 1.39261000 H -1.54794500 0.81181600 -4.58632500 H -0.35954300 2.16061000 -4.52536000 H -0.18519200 0.86956200 -5.75929000 H 2.23665500 0.30360300 -4.91080100 H 2.06818500 1.70030500 -3.80962800 H 2.51110400 0.08274100 -3.15253700 H -0.81199100 -1.58950900 -3.99291300 H 0.58168800 -1.45190700 -5.13015200 H 0.86098300 -1.89093400 -3.40365000

67

O 1.36095100 0.73421700 1.82769000 C 1.90577200 0.26804700 2.84684800 H 2.70363500 -0.51207300 2.78052900 N 1.58394000 0.64095200 4.10793800 C 2.31746300 0.13031700 5.25497300 C 0.48599200 1.57403800 4.34206300 H 2.81523600 0.95484800 5.81187800 H 1.63687400 -0.39936500 5.95662600 H 3.09464200 -0.58150700 4.91412800 H 0.86641300 2.58851300 4.59511600 H -0.14117100 1.62928500 3.42883300 H -0.13124700 1.21206900 5.19065800 122 Dimer 5 DMF O bound Ni -1.46400000 0.74601900 -0.14336100 N 0.60114700 1.16200600 -0.80710400 N -1.49841900 2.79491600 -0.17296200 O 1.05224300 -0.72316500 -1.90959700 O -4.42439500 -1.11543400 -0.27862600 O -3.43571400 0.77868700 0.47816700 C 0.85344800 0.52152500 -1.99366700 C 0.87355700 1.19199000 -3.39487700 C 0.44952500 0.13145100 -4.43717200 C 2.32223300 1.63708200 -3.72282800 C -0.07738700 2.40476500 -3.48865100 C 0.86088800 2.51097000 -0.53650900 C 2.15235000 3.05694500 -0.49419800 C 2.35489500 4.42718400 -0.18762800 C 1.28636800 5.27394800 0.09452800 C -0.04208600 4.75439300 0.10397500 C -0.24907700 3.36031500 -0.19160000 C -1.20034000 5.53678200 0.38906100 C -2.45425800 4.94001000 0.38126800 C -2.56031200 3.55176500 0.10721000 C -4.41959200 -0.04798600 0.37963300 C -5.74849400 0.37331000 1.10310700 C -6.36971800 -0.87782500 1.75977800 C -6.70458200 0.89804900 0.00389300 C -5.51602300 1.46687500 2.16067300 Ni 1.49584000 -0.62462600 0.15768100 N -0.60276800 -1.13494600 0.68528100 N 1.65527900 -2.65962300 0.33218200 O -1.05281400 0.67181800 1.90735700 O 4.86269800 -1.22171100 0.77591700 O 3.39047500 -0.07102900 -0.50917700 C -0.89459100 -0.58438700 1.90387300 C -1.07796700 -1.34889000 3.24018100 C -0.76711900 -0.37593400 4.40031700 C -2.56854400 -1.76985500 3.33784100 C -0.16545900 -2.58727000 3.36804300

68

C -0.75100400 -2.49056200 0.33294000 C -1.99299600 -3.08680300 0.07822300 C -2.07821100 -4.46255700 -0.26453600 C -0.94223500 -5.25833200 -0.36875400 C 0.34511900 -4.67989000 -0.16235300 C 0.44051600 -3.27847800 0.15462400 C 1.56330000 -5.41747100 -0.23668300 C 2.76998400 -4.77596900 0.00279500 C 2.77816200 -3.38234700 0.27532200 C 4.57080100 -0.49800200 -0.21104600 C 5.71402400 -0.10465300 -1.20700800 C 7.08611300 -0.44840300 -0.59774400 C 5.49255400 -0.93073500 -2.49738200 C 5.64975800 1.40083500 -1.53524400 H -6.47003900 1.71883200 2.67337300 H -4.78893200 1.13752400 2.93078900 H -5.11429500 2.39615000 1.71041500 H -6.28679000 1.79533300 -0.50201300 H -7.68634600 1.18526700 0.43930000 H -6.88305100 0.11676800 -0.76350600 H -6.47611900 -1.68932600 1.01368900 H -5.73024600 -1.25861400 2.58369800 H -7.36908500 -0.64379800 2.18626400 H -1.09168100 2.14718400 -3.12585900 H -0.15752900 2.72766700 -4.54831200 H 0.28975000 3.27418700 -2.90950500 H 0.53724600 0.55898800 -5.45815400 H 1.08888300 -0.76950800 -4.37106100 H -0.60029600 -0.18038900 -4.27716700 H 2.67037500 2.44355200 -3.04862600 H 2.35952600 2.02398900 -4.76367600 H 3.02912600 0.78781000 -3.64482300 H 3.71615300 -2.82555300 0.45806500 H 3.72586400 -5.32030200 -0.02860100 H 1.52766100 -6.49317900 -0.47596100 H -1.01593600 -6.33001300 -0.61365000 H -3.07352400 -4.90184300 -0.44152600 H -2.90431100 -2.46309100 0.11262700 H -3.52029100 3.01303000 0.14803700 H -3.36479700 5.51824500 0.59953000 H -1.08408800 6.60919800 0.61652900 H 1.44897400 6.33981100 0.32010800 H 3.38342200 4.82289200 -0.17622900 H 3.00181600 2.38459100 -0.68424800 H 7.27452100 0.13656100 0.32633900 H 7.14214700 -1.51934300 -0.32193300 H 7.89921900 -0.22149900 -1.32094300 H 6.25676800 -0.67636000 -3.26361700 H 5.56732400 -2.01935100 -2.29151700 H 4.48744700 -0.73521800 -2.92218600 H 6.45330500 1.67992300 -2.25080000

69

H 4.67646500 1.66520100 -1.99058800 H 5.78476600 2.01903500 -0.62181200 H -3.23198000 -0.88601800 3.24991900 H -2.84839900 -2.49211900 2.54635800 H -2.75499400 -2.24812000 4.32319600 H -0.21576700 -2.97275400 4.40842400 H -0.47396000 -3.41264000 2.69858000 H 0.89070200 -2.33529400 3.14534500 H -1.37814600 0.54357400 4.32618400 H -0.98249500 -0.87357600 5.36925400 H 0.29989200 -0.07873900 4.39121600 O 1.85251300 0.18527200 2.02551100 C 2.98548300 0.23375700 2.55811100 H 3.81716300 -0.43244000 2.21094800 N 3.29538300 1.10284500 3.54937700 C 4.62504300 1.10069700 4.14150600 C 2.32744000 2.08243600 4.02891900 H 5.10542200 2.09799700 4.03350900 H 4.58130300 0.85555900 5.22583800 H 5.25525100 0.34806100 3.62925200 H 2.72650100 3.11199600 3.90125700 H 1.39695500 1.97193300 3.44152000 H 2.10576600 1.92383700 5.10653600 O -1.96755100 -0.01609500 -2.00105100 C -3.13607800 -0.14281600 -2.42764400 H -3.93517100 0.59467000 -2.18902200 N -3.52492000 -1.12271000 -3.27213500 C -4.92316900 -1.26069500 -3.64624400 C -2.62621400 -2.22308600 -3.59959700 H -5.02408900 -1.39396100 -4.74480700 H -5.38230600 -2.13411400 -3.13402100 H -5.48177700 -0.35415400 -3.34439200 H -2.54374100 -2.34398300 -4.70077800 H -1.63041600 -2.00798600 -3.17140600 H -3.00685400 -3.17207600 -3.16350600 61 Monomer 5 1 DMF Ni 0.27885600 0.20707600 0.14208200 N -1.51056900 1.07834200 -0.06986300 N -0.51702900 -1.25111500 -0.95083200 O -3.01810200 2.81459900 0.28033500 O 1.59541500 1.05349900 -1.29751300 O 2.28522700 -0.48983700 0.12143600 C -1.88028700 2.32872400 0.38110300 C -0.74484800 3.21814000 0.98727900 C -1.38396200 4.18323900 2.00731800 C -0.13751200 4.02323700 -0.19049300 C 0.36341500 2.41515600 1.68955800 C -2.39573300 0.24446200 -0.74098700 C -3.76383200 0.47055100 -1.02507900

70

C -4.53180700 -0.48035400 -1.73983500 C -3.99946900 -1.68173400 -2.20315000 C -2.62963400 -1.96866200 -1.94798200 C -1.83823100 -1.00845000 -1.21766000 C -1.97355400 -3.16131400 -2.37444300 C -0.62939500 -3.36752800 -2.08611600 C 0.07456300 -2.37514600 -1.35975900 C 2.52510300 0.29613800 -0.86536700 C 3.91494500 0.34169800 -1.52741300 C 4.46490000 1.78037400 -1.36592800 C 3.73651700 0.02400000 -3.03179700 C 4.86736700 -0.67305500 -0.86933500 H 5.86798900 -0.62580800 -1.34897000 H 4.99118200 -0.46678900 0.21293100 H 4.48600900 -1.70963400 -0.96890400 H 3.34460500 -1.00378500 -3.18393200 H 4.71146300 0.09787600 -3.55867200 H 3.02581800 0.73336000 -3.50003800 H 3.77067700 2.51881800 -1.81367400 H 4.60297300 2.04157300 -0.29552400 H 5.45103800 1.87271900 -1.86849100 H -0.03409200 1.71701900 2.45168800 H 1.07996000 3.10098300 2.19280100 H 1.00952400 1.86076800 0.95898200 H -0.63743600 4.92430000 2.36405000 H -2.23539100 4.71737800 1.54432900 H -1.77620600 3.63516400 2.89022300 H 0.34314100 3.34671200 -0.92645500 H 0.63134900 4.73561400 0.18081100 H -0.92624000 4.60649700 -0.70817800 H 1.14119400 -2.48259600 -1.10162800 H -0.10604300 -4.27973100 -2.41042800 H -2.54929300 -3.91428900 -2.93756400 H -4.61298400 -2.40717600 -2.75995700 H -5.59251200 -0.24964300 -1.93341400 H -4.20764100 1.41003900 -0.67719800 O -0.15213900 -0.76966300 1.95478100 C 0.67717300 -1.57742000 2.42255500 H 1.67392000 -1.72806100 1.94170500 N 0.45497600 -2.32368600 3.52983000 C 1.46811500 -3.23610900 4.03930900 C -0.80875700 -2.22870000 4.25289700 H 1.77111400 -2.95700900 5.07215200 H 1.08621900 -4.28014100 4.06120600 H 2.36319500 -3.20075000 3.38829500 H -0.63966000 -1.86821100 5.29052600 H -1.46491300 -1.51739900 3.71854000 H -1.30222500 -3.22296300 4.30218400 73 Monomer 5 2 DMF trans

71

Ni -0.33544300 0.03180200 0.05449400 N 1.28814600 0.19078600 -1.24477700 N 0.79025100 1.24393200 1.19669900 O 2.69852500 -1.42870900 -2.11304800 O -1.97516200 -1.25707000 -0.50978500 O -1.90046500 -0.30695100 1.48672800 C 1.61384300 -0.81886600 -2.13833800 C 0.57443200 -1.21016800 -3.23121400 C 1.35876700 -1.29814200 -4.56453200 C -0.57248800 -0.19619300 -3.38525900 C 0.01608600 -2.61162000 -2.88030100 C 2.29946300 0.90444600 -0.63585300 C 3.59441900 1.14818100 -1.16017000 C 4.50382500 2.00938800 -0.50930200 C 4.20319700 2.65085600 0.69589900 C 2.93772600 2.41565900 1.29683500 C 2.00044900 1.53757700 0.63446300 C 2.51964400 2.98100400 2.53965800 C 1.27691200 2.66314000 3.07620800 C 0.43004400 1.77069900 2.36966400 C -2.45901700 -1.11014000 0.65611800 C -3.70091200 -1.92947000 1.07146400 C -3.25324200 -3.40921300 1.17573800 C -4.77453600 -1.79425800 -0.03181600 C -4.24954500 -1.44609300 2.42629900 H -5.11981100 -2.06465100 2.73348000 H -3.47647900 -1.50929700 3.21763600 H -4.58360600 -0.38892600 2.37518300 H -5.13242400 -0.74624300 -0.12067200 H -5.65339500 -2.43304300 0.19998900 H -4.36289400 -2.09684100 -1.01468400 H -2.83611700 -3.76226300 0.21160400 H -2.47327700 -3.53798300 1.95521600 H -4.11621400 -4.05500900 1.44546900 H 0.84789600 -3.33489500 -2.75496300 H -0.64303100 -2.97694300 -3.69772400 H -0.57812500 -2.57907800 -1.94594600 H 0.69336800 -1.66235500 -5.37621200 H 1.75213200 -0.30405600 -4.86822800 H 2.21870100 -1.98859200 -4.46415400 H -1.21366100 -0.15822100 -2.48589700 H -1.21389600 -0.48561700 -4.24651700 H -0.18235200 0.82518700 -3.57465700 H -0.55575500 1.46143500 2.75635700 H 0.94390200 3.08513700 4.03690000 H 3.20128800 3.66661600 3.07009500 H 4.92787600 3.31786500 1.18823400 H 5.48891700 2.17595300 -0.97629400 H 3.88916000 0.65227800 -2.09378000 O 0.65873000 -1.72645400 0.67084700 C 1.23059300 -1.92988300 1.75592600

72

H 0.87894900 -1.46786900 2.71341300 N 2.32420000 -2.71533000 1.88935400 C 2.87816600 -3.01961600 3.19947600 C 2.94157100 -3.32297700 0.70801300 H 2.81159100 -4.10767000 3.42214700 H 3.94702600 -2.71995600 3.25616900 H 2.31647500 -2.46976900 3.98040900 H 2.51575700 -4.32995000 0.50435000 H 2.78581000 -2.67547700 -0.18041900 H 4.02950700 -3.42985600 0.88987800 O -1.34571800 1.71146600 -0.72792300 C -2.36952200 2.19151800 -0.20987800 H -2.81905200 1.74898600 0.71264500 N -3.02845700 3.27158900 -0.70060900 C -4.22288000 3.78647300 -0.05056000 C -2.55630800 3.94751000 -1.90337200 H -4.07786600 4.84055100 0.27396400 H -5.09658300 3.75468300 -0.73816600 H -4.45607500 3.17299000 0.84162000 H -2.31596500 5.01053300 -1.68481500 H -1.64688900 3.42957000 -2.25966000 H -3.33285100 3.91833900 -2.69801300 90 6 dimer DMF Ni -0.84449500 0.15094300 0.85157100 O 0.29024600 -1.20799600 1.81872100 O 1.74019900 -1.39463600 0.10046700 O -1.77321900 -1.34899800 -0.13694900 O -0.30194900 -1.15452500 -1.83272300 C 1.28454900 -1.74855200 1.23570600 C -1.33494700 -1.66364600 -1.29096500 C 1.98513300 -2.90770500 1.99129600 C 2.57124400 -2.32510500 3.30013900 C 3.10319500 -3.52906000 1.13547100 C 0.91845800 -3.97460800 2.33188100 C -2.09530500 -2.73622300 -2.11163800 C -3.23661400 -3.35555400 -1.28531300 C -1.08707500 -3.83006000 -2.53412300 C -2.66229600 -2.03941400 -3.37271900 Ni 0.83700800 0.17017000 -0.83979600 O -0.10138200 1.73390600 -1.65910800 O -1.84410300 1.52614200 -0.24897300 O 1.89370700 1.42104600 0.35704900 O 0.15216500 1.64172800 1.76706400 C -1.26282800 2.05760100 -1.25130600 C 1.31268100 1.95718300 1.36102500 C -1.98145500 3.19357700 -2.02044300 C -2.01879300 2.81679800 -3.51990300 C -3.40820700 3.40843000 -1.48461200 C -1.14166200 4.48091500 -1.82987900

73

C 2.09312900 3.05234300 2.13015100 C 2.47363500 4.16777700 1.12821100 C 1.23586500 3.62784200 3.27230100 C 3.37796400 2.40720300 2.70315600 H 3.07029300 4.95453400 1.63740400 H 3.06939300 3.75949200 0.28795700 H 1.56926400 4.64920000 0.70104300 H 3.13438400 1.59071400 3.41484000 H 4.00483200 1.98393600 1.89308700 H 3.97783000 3.16690200 3.24839000 H 0.30085400 4.07956700 2.88478000 H 1.80385200 4.41205300 3.81695400 H 0.94479000 2.83920900 3.99421000 H 0.09538000 -3.52783100 2.92336800 H 0.47963600 -4.41294000 1.41085800 H 1.37249400 -4.80076100 2.91977300 H 3.87901700 -2.77893600 0.88217700 H 3.59085200 -4.36082700 1.68738600 H 2.70525200 -3.92949400 0.18127300 H 1.77422100 -1.85826900 3.91226100 H 3.33804500 -1.55091900 3.08648300 H 3.05384000 -3.12765500 3.89808000 H -0.24830900 -3.38790400 -3.10653600 H -0.66188400 -4.34833100 -1.64900800 H -1.58846800 -4.59268000 -3.16749600 H -3.18867800 -2.77600700 -4.01667300 H -1.84847600 -1.57275900 -3.96265400 H -3.38857700 -1.24486600 -3.10013900 H -3.96802800 -2.58480800 -0.96971500 H -3.77345700 -4.11994300 -1.88662000 H -2.85096900 -3.84218200 -0.36679200 H -3.90063800 4.23837200 -2.03473100 H -4.02822800 2.49760100 -1.61214500 H -3.40003500 3.66062500 -0.40552200 H -2.48434900 3.63482600 -4.10997000 H -0.99567200 2.63852800 -3.90519500 H -2.61301100 1.89414400 -3.68867700 H -1.59662900 5.32267300 -2.39435900 H -1.09490700 4.77381700 -0.75995900 H -0.10572600 4.33063400 -2.19322700 O 2.31928300 0.12754300 -2.35776900 C 3.27919000 -0.56911200 -2.71063400 H 3.24311800 -1.17798900 -3.65302900 N 4.46915700 -0.67210800 -2.06590800 C 5.53385700 -1.51531000 -2.58387600 C 4.71879800 0.05195100 -0.82449700 H 6.45243200 -0.91972500 -2.78136200 H 5.79311200 -2.31906900 -1.86023900 H 5.21073400 -1.98859600 -3.53227000 H 5.57710500 0.74715000 -0.95463500 H 3.81291900 0.62062800 -0.54117700

74

H 4.96378200 -0.66043000 -0.00848700 O -2.33740300 0.07419200 2.35774400 C -3.30315700 -0.62976700 2.67688000 H -3.26147300 -1.31546500 3.56473900 N -4.50838100 -0.65321400 2.05159400 C -5.58558600 -1.50685900 2.52398700 C -4.75954000 0.17503400 0.87762400 H -6.48281500 -0.90544900 2.79016400 H -5.88240100 -2.24243200 1.74437100 H -5.25600000 -2.06372400 3.42353200 H -5.58942100 0.88687200 1.08077700 H -3.84035800 0.73500300 0.62161300 H -5.04648800 -0.46169700 0.01390400 65 NI(AQPiv)2 Ni -0.00145200 0.04803600 0.28026400 O 3.53217200 -1.98563200 1.39640100 N 0.79979700 1.22129200 -1.11386600 N -1.91849100 0.63823100 0.43875500 N -0.73361900 -1.29179900 -1.00163800 N 1.90200300 -0.53760300 0.58654100 O -3.63212800 2.01815900 1.19419800 C 2.93247400 1.86906000 -2.11271400 C -2.08650400 -1.15447600 -1.16739100 C 2.16212100 1.09242700 -1.17276400 C 4.18789400 0.04388500 -0.33456700 H 4.68595000 -0.66731000 0.33253300 C -2.80299800 -2.00803000 -2.08289300 C 4.34722700 1.71756300 -2.13557400 H 4.94650500 2.30802600 -2.84592000 C 1.35494300 -2.30592400 2.33513000 C 2.77972900 0.14955500 -0.26161400 C -2.74946900 -0.12206300 -0.39469100 C 0.82927900 2.84244900 -2.88875700 H 0.25664200 3.51567600 -3.54382300 C 2.21410900 2.75144900 -2.97171800 H 2.77403500 3.35832200 -3.70197900 C -4.20973900 -1.84391800 -2.22148100 H -4.76784300 -2.49297100 -2.91403500 C 0.14791400 2.05075100 -1.93240700 H -0.94790900 2.09104100 -1.81908600 C -1.49622600 2.43565500 2.19073500 C -0.04104800 -2.20001600 -1.69355900 H 1.04485000 -2.23522200 -1.50795000 C 2.36315600 -1.57055100 1.38951400 C 2.04457400 -2.43833800 3.71432600 H 2.19405300 -1.44422200 4.18659400 H 3.03808500 -2.91211100 3.59805000 H 1.42601500 -3.05427600 4.40078500 C -0.66876400 -3.07275500 -2.61536800

75

H -0.06371800 -3.81012100 -3.16350000 C -4.84615600 -0.86046000 -1.47109400 H -5.93577900 -0.72504800 -1.56813600 C 4.93942400 0.82070400 -1.25187500 H 6.03469400 0.69686400 -1.25868600 C -2.04293100 -2.97605800 -2.80228300 H -2.56186800 -3.64318700 -3.50990000 C -4.14756100 -0.00994400 -0.57760800 H -4.67875000 0.76013200 -0.00871900 C -2.43971300 1.67670500 1.19783500 C 0.00264800 -1.60974800 2.52802500 H -0.57649600 -1.51169100 1.57770500 H 0.11236100 -0.61342700 3.00068200 H -0.65341000 -2.21034300 3.19496500 C 0.00736800 2.29789600 1.91826100 H 0.59316000 2.81559400 2.70857900 H 0.30142700 2.74281200 0.94817500 H 0.36459500 1.23877000 1.95619400 C -1.83219800 1.88298700 3.60068400 H -1.58365400 0.80462400 3.68712800 H -2.91422200 2.00034100 3.81022800 H -1.26099800 2.43071300 4.38055400 C 1.13772200 -3.72059400 1.74075600 H 0.52633400 -4.34274600 2.42876700 H 2.11316100 -4.22319200 1.58471700 H 0.60939800 -3.67633600 0.76514700 C -1.86948200 3.93527600 2.13626600 H -1.32007600 4.50095600 2.91804900 H -2.95749000 4.06318100 2.29268500 H -1.61333800 4.37816000 1.15040400 12 DMF C -0.86566100 -0.65480800 -0.00000100 H -0.73864400 -1.77675900 -0.00000100 O -1.95937600 -0.10509100 0.00000300 N 0.35463400 -0.01609700 -0.00001100 C 1.60194800 -0.75381500 0.00000300 H 2.21580900 -0.52063200 -0.89974300 H 2.21580300 -0.52059700 0.89974400 H 1.38737700 -1.84199000 0.00002500 C 0.40870400 1.43630300 0.00000000 H 0.93788200 1.81880000 -0.90129400 H -0.63344500 1.80972300 -0.00001400 H 0.93784400 1.81878900 0.90132500 10 DMSO S 0.00000100 0.24439300 -0.45229900 C 1.37870600 -0.82540300 0.18497000 H 1.37364400 -1.81354300 -0.31800800

76

H 2.31404300 -0.28132000 -0.04907100 H 1.26580600 -0.92358100 1.28317000 C -1.37872100 -0.82537900 0.18497200 H -1.26579900 -0.92362300 1.28316300 H -2.31404100 -0.28124600 -0.04901800 H -1.37371300 -1.81349300 -0.31805900 O 0.00001600 1.50390100 0.39812000

Table S2. Crystal data and structural refinement of 3

Empirical formula C34H36N4NiO2

Formula weight 591.38

Temperature 170(2) K

Wavelength 0.71073 Å

Crystal system Triclinic

Space group P -1

Unit cell dimensions a = 10.0177(7) Å a= 73.138(2)°.

b = 10.8842(8) Å b= 71.793(2)°.

c = 15.3549(12) Å g = 72.856(2)°.

Volume 1483.15(19) Å3

Z 2

Density (calculated) 1.324 Mg/m3

Absorption coefficient 0.691 mm-1

F(000) 624

Crystal size 0.15 x 0.20 x 0.15 mm3

Theta range for data collection 2.904 to 29.999°.

Index ranges -14<=h<=14, -15<=k<=15, -21<=l<=21

Reflections collected 61790

Independent reflections 8646 [R(int) = 0.0332]

Completeness to theta = 29.999° 99.8 %

Refinement method Full-matrix least-squares on F2

Data / restraints / parameters 8646 / 0 / 376

Goodness-of-fit on F2 1.032

Final R indices [I>2sigma(I)] R1 = 0.0378, wR2 = 0.0895

R indices (all data) R1 = 0.0489, wR2 = 0.0948

Extinction coefficient n/a

Largest diff. peak and hole 0.506 and -0.513 e.Å-3

77

Table S3. Crystal data and structure refinement for 5.

Empirical formula C45H56N4O6Ni2

Formula weight 866.35

Temperature/K 170(2)

Crystal system triclinic

Space group P-1

a/Å 9.678(6)

b/Å 11.382(7)

c/Å 11.733(8)

α/° 63.862(14)

β/° 74.501(16)

γ/° 66.921(15)

Volume/Å3 1060.4(12)

Z 1

ρcalcg/cm3 1.357

μ/mm-1 0.940

F(000) 458.0

Crystal size/mm3 0.190 × 0.140 × 0.050

Radiation MoKα (λ = 0.71073)

2Θ range for data collection/° 5.68 to 49.988

Index ranges -11 ≤ h ≤ 11, -13 ≤ k ≤ 13, -13 ≤ l ≤ 13

Reflections collected 8231

Independent reflections 8231 [Rint = ?, Rsigma = 0.0894]

Data/restraints/parameters 8231/28/324

Goodness-of-fit on F2 1.058

Final R indexes [I>=2σ (I)] R1 = 0.0647, wR2 = 0.1324

Final R indexes [all data] R1 = 0.1037, wR2 = 0.1545

Largest diff. peak/hole / e Å-3 0.49/-0.58

78

Scheme S3: X-ray structure of 6·PPh3 (CCDC 2055452).

Table S4. Crystal data and structure refinement for 6·PPh3.

Empirical formula C62H72Ni2O8P2

Formula weight 1124.55

Temperature/K 170(2)

Crystal system triclinic

Space group P-1

a/Å 11.5996(11)

b/Å 11.9251(11)

c/Å 12.1970(12)

α/° 65.773(3)

β/° 84.310(3)

γ/° 69.990(3)

Volume/Å3 1444.0(2)

Z 1

ρcalcg/cm3 1.293

μ/mm-1 0.760

F(000) 594.0

Crystal size/mm3 0.22 × 0.20 × 0.25

Radiation MoKα (λ = 0.71073)

2Θ range for data collection/° 6.298 to 71.998

Index ranges -19 ≤ h ≤ 19, -19 ≤ k ≤ 19, -20 ≤ l ≤ 20

Reflections collected 84896

Independent reflections 13649 [Rint = 0.0419, Rsigma = 0.0328]

Data/restraints/parameters 13649/0/340

Goodness-of-fit on F2 1.039

Final R indexes [I>=2σ (I)] R1 = 0.0325, wR2 = 0.0738

79

Final R indexes [all data] R1 = 0.0536, wR2 = 0.0827

Largest diff. peak/hole / e Å-3 0.47/-0.58

Table S5. Crystal data and structural refinement of 7·PPh3

Empirical formula C40H45N2NiO3P

Formula weight 691.46

Temperature/K 170(2)

Crystal system monoclinic

Space group P21/c

a/Å 9.2352(5)

b/Å 16.4163(8)

c/Å 23.3026(13)

α/° 90

β/° 98.555(2)

γ/° 90

Volume/Å3 3493.5(3)

Z 4

ρcalcg/cm3 1.315

μ/mm-1 0.642

F(000) 1464.0

Crystal size/mm3 0.10 × 0.15 × 0.12

Radiation MoKα (λ = 0.71073)

2Θ range for data collection/° 5.82 to 55

Index ranges -11 <= h <=11, -21 <= k <= 21, -30 <= l <= 30

Reflections collected 55880

Independent reflections 8005 [Rint = 0.0708, Rsigma = 0.0547]

Data/restraints/parameters 8005/66/458

Goodness-of-fit on F2 1.011

Final R indexes [I>=2σ (I)] R1 = 0.0428, wR2 = 0.0821

Final R indexes [all data] R1 = 0.0872, wR2 = 0.0984

Largest diff. peak/hole / e Å-3 0.42/-0.37

Table S6. Crystal data and structural refinement of 7·PiBu3

Empirical formula C33H49N2NiOP

Formula weight 579.42

80

Temperature 170(2) K

Wavelength 0.71073 Å

Crystal system Monoclinic

Space group P 21/n

Unit cell dimensions a = 9.9900(4) Å a= 90°.

b = 19.5904(6) Å b= 103.3670(10)°.

c = 17.1248(6) Å g = 90°.

Volume 3260.7(2) Å3

Z 4

Density (calculated) 1.180 Mg/m3

Absorption coefficient 0.670 mm-1

F(000) 1248

Crystal size 0.15 x 0.10 x 0.12 mm3

Theta range for data collection 2.952 to 24.999°.

Index ranges -11<=h<=11, -23<=k<=23, -20<=l<=20

Reflections collected 34354

Independent reflections 5725 [R(int) = 0.0559]

Completeness to theta = 24.999° 99.8 %

Refinement method Full-matrix least-squares on F2

Data / restraints / parameters 5725 / 32 / 413

Goodness-of-fit on F2 1.051

Final R indices [I>2sigma(I)] R1 = 0.0409, wR2 = 0.0810

R indices (all data) R1 = 0.0603, wR2 = 0.0889

Extinction coefficient n/a

Largest diff. peak and hole 0.300 and -0.392 e.Å-3

Table S7. Crystal data and structure refinement for 8.

Empirical formula C40H38N4NiO2

Formula weight 665.45

Temperature 170(2) K

Wavelength 0.71073 Å

Crystal system Monoclinic

Space group P 21/c

Unit cell dimensions a = 14.5467(8) Å a= 90°.

b = 19.2619(10) Å b= 112.241(2)°.

c = 12.4604(8) Å g = 90°.

Volume 3231.6(3) Å3

Z 4

Density (calculated) 1.368 Mg/m3

Absorption coefficient 0.643 mm-1

81

F(000) 1400

Crystal size 0.310 x 0.250 x 0.220 mm3

Theta range for data collection 2.924 to 25.425°.

Index ranges -17<=h<=17, -23<=k<=23, -15<=l<=15

Reflections collected 117278

Independent reflections 5951 [R(int) = 0.0732]

Completeness to theta = 25.425° 99.7 %

Refinement method Full-matrix least-squares on F2

Data / restraints / parameters 5951 / 0 / 428

Goodness-of-fit on F2 1.043

Final R indices [I>2sigma(I)] R1 = 0.0314, wR2 = 0.0733

R indices (all data) R1 = 0.0433, wR2 = 0.0793

Extinction coefficient n/a

Largest diff. peak and hole 0.310 and -0.427 e.Å-3

82

1. Monnereau, C.; Blart, E.; Odobel, F., A cheap and efficient method for selective para-iodination of aniline derivatives. Tetrahedron Letters 2005, 46, 5421-5423. 2. Shabashov, D.; Daugulis, O., Auxiliary-Assisted Palladium-Catalyzed Arylation and Alkylation of sp2 and sp3 Carbon-Hydrogen Bonds. J. Am. Chem. Soc. 2010, 132, 3965-3972. 3. Zeller, A.; Herdtweck, E.; Strassner, T., Structural Characterization and a New One-Pot Synthesis of trans-Chloro(phenyl)bis(triphenylphosphane)nickel(II). Eur. J. Inorg. Chem. 2003, 1802-1806. 4. Yan, J.-X.; Li, H.; Xiang-Wei, L.; Shi, J.-L.; Wang, X.; Shi, Z.-J., Palladium-Catalyzed C(sp3)-H Activation: A Facile Method for theSynthesis of 3,4-Dihydroquinolinone Derivatives. Angew. Chem. Int. Ed. 2014, 53, 4945-4949. 5. Li, M.; Dong, J.; Huang, X.; Li, K.; Wu, Q.; Song, F.; You, J., Nickel-catalyzed chelation-assisted direct arylation of unactivated C(sp3)–H bonds with aryl halides. Chem. Comm 2014, 50, 3944. 6. Gaussian 16, Revision B.01, Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Scuseria, G. E.; Robb, M. A.; Cheeseman, J. R.; Scalmani, G.; Barone, V.; Petersson, G. A.; Nakatsuji, H.; Li, X.; Caricato, M.; Marenich, A. V.; Bloino, J.; Janesko, B. G.; Gomperts, R.; Mennucci, B.; Hratchian, H. P.; Ortiz, J. V.; Izmaylov, A. F.; Sonnenberg, J. L.; Williams-Young, D.; Ding, F.; Lipparini, F.; Egidi, F.; Goings, J.; Peng, B.; Petrone, A.; Henderson, T.; Ranasinghe, D.; Zakrzewski, V. G.; Gao, J.; Rega, N.; Zheng, G.; Liang, W.; Hada, M.; Ehara, M.; Toyota, K.; Fukuda, R.; Hasegawa, J.; Ishida, M.; Nakajima, T.; Honda, Y.; Kitao, O.; Nakai, H.; Vreven, T.; Throssell, K.; Montgomery, J. A., Jr.; Peralta, J. E.; Ogliaro, F.; Bearpark, M. J.; Heyd, J. J.; Brothers, E. N.; Kudin, K. N.; Staroverov, V. N.; Keith, T. A.; Kobayashi, R.; Normand, J.; Raghavachari, K.; Rendell, A. P.; Burant, J. C.; Iyengar, S. S.; Tomasi, J.; Cossi, M.; Millam, J. M.; Klene, M.; Adamo, C.; Cammi, R.; Ochterski, J. W.; Martin, R. L.; Morokuma, K.; Farkas, O.; Foresman, J. B.; Fox, D. J. Gaussian, Inc., Wallingford CT, 2016.

download fileview on ChemRxivSI_Mechanism_Ni_CH_arylation_SJ.pdf (5.47 MiB)