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SYNTHESIS0 0 3 9 - 7 8 8 1 1 4 3 7 - 2 1 0 X© Georg Thieme Verlag Stuttgart · New York2020, 52, 834–846featureen
rial.
Alkyl Tosylates as Alkylating Reagents in the Catellani ReactionQianwen Gaoa Ze-Shui Liua Yu Huaa Siwei Zhoua Hong-Gang Cheng*a Qianghui Zhou*a,b
a Sauvage Center for Molecular Sciences, Engineering Research Center of Organosilicon Compounds & Materials (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, 430072 Wuhan, P. R. of [email protected]@whu.edu.cn
b The Institute for Advanced Studies, Wuhan University, 430072 Wuhan, P. R. of China
Pd/NBEcooperative catalysis
+ R3
IR1 R1
R3
R2
+
CN(±)
45 examplesup to 97% yield
NBE-CN as the catalytic mediator broad substrate scopeeasily accessible starting materials
[NBE](20 mol%)
scalable protocol
R2 OTs
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Received: 18.11.2019Accepted after revision: 20.12.2019Published online: 30.01.2020DOI: 10.1055/s-0039-1690801; Art ID: ss-2019-z0637-fa
Abstract A cooperative catalytic system involving a Pd/XPhos complexand inexpensive 5-norbornene-2-carbonitrile that enables the use of al-kyl tosylates as alkylating reagents in the Catellani reaction has beendeveloped. This mild, scalable protocol is compatible with a range ofreadily available functionalized aryl iodides and alkyl tosylates, as well asterminating olefins (45 examples, up to 97% yield).
Key words Catellani reaction, cooperative catalysis, alkyl tosylates,5-norbornene-2-carbonitrile, polysubstituted arenes
The development of straightforward strategies to as-semble complex molecular scaffolds represents one of thecentral tasks in modern organic synthesis.1 Therein, thetransition-metal-catalyzed C–H functionalization of arenesis among the most attractive strategies.2 It can build variousC–C and C–X bonds in a direct and selective approach andthus gains much attention in both academic and industriallaboratories.
In this context, the Catellani-type reaction3 is known asone of the most promising approaches to accomplish theseprocesses. It utilizes the synergistic interplay of palladiumand 2-norbornene (NBE) catalysis to facilitate sequentialortho C–H functionalization and ipso termination of arylhalides in a single operation, thereby allowing the simulta-neous functionalization of ortho and ipso positions to per-mit the expeditious syntheses of highly substituted arenes,which are usually difficult to access through traditionalcross-coupling reactions. Since the pioneering work by thegroups of Catellani4 and Lautens,5 this chemistry has at-tracted tremendous attention in the synthetic organic com-munity. Significant progress has been made over twentyyears of development; especially, the exploration of termi-nating reagents has been well studied.6 However, the devel-
opment of electrophilic reagents for ortho C–H functional-ization was relatively lagging behind until 2018, and wasmainly limited to alkyl halides,3j,4 aryl halides,7 azirines,8 O-benzoylhydroxylamines,9 and various carboxylic acid deriv-atives.10 Since 2018, rapid progress has been made in thisdirection. For instance, epoxides and aziridines were suc-cessfully employed as alkylating reagents in Catellani-typereactions by Dong,11 Liang,12 and our group.13 Moreover,hexamethyldisilane, hexamethyldigermane, and hexa-butyldistannane as electrophilic reagents were also report-ed by the Cheng group (Scheme 1a).14 Later, the Dong andGu groups independently reported an ortho-thiolation re-action via rational design of S-containing electrophiles.15
Recently, our group reported a dual-tasked methylationof aryl iodides through Pd/NBE cooperative catalysis, withinexpensive methyl tosylate and trimethyl phosphate as themethylating reagent (Scheme 1b).16 It was found that the io-dide ion17 can react with methyl tosylate to slowly releaseiodomethane in situ,18 and significantly reduce the possibleside reactions. The Dong group also realized similar methyl-ation of aryl bromides or alkenyl triflates using methyl 4-nitrobenzenesulfonate19 or phenyltrimethylammoniumsalt20 as the methylating reagent, respectively. Inspired bythis chemistry, we envisaged whether alkyl tosylates gener-ally can serve as alkylating reagents to react with aryl io-dides and olefins in a Catellani-type process. The use of al-kyl tosylates instead of alkyl halides has several advantages.Firstly, they can be easily prepared from inexpensive andabundant alcohols, which are feedstock chemicals. Second-ly, the generation of halide-containing waste would be re-duced, thereby decreasing the environmental impact. Last-ly, the slow release mechanism would maintain a low con-centration of the active alkyl iodides, thus diminishing thepotential competitive side reactions. As part of our continu-ing efforts in exploring novel Catellani-type reactions,13,21
herein we describe the development of an ortho-C–H
© 2020. Thieme. All rights reserved. Synthesis 2020, 52, 834–846Georg Thieme Verlag KG, Rüdigerstraße 14, 70469 Stuttgart, Germany
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Biographical Sketches
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Qianwen Gao received herB.Sc. degree in chemistry fromHunan Normal University in2016. In the fall of 2016, she be-
gan graduate study at WuhanUniversity under the directionof Prof. Qianghui Zhou. Her re-search focuses on synthetic
methodology developmentsand asymmetric catalysis.
Ze-Shui Liu received his B.S.degree from Yangtze Universityin 2011. After earning his M.S.degree from China West NormalUniversity in 2015, he pursued
and received his Ph.D. in 2018,under the guidance of Prof.Qianghui Zhou at Wuhan Uni-versity. Currently, he is workingas a postdoctoral fellow in the
group of Prof. Qianghui Zhou.His research interests includesynthetic methodology devel-opments and asymmetric catal-ysis.
Yu Hua received his B.Sc. de-gree from Guangxi University in2017. In the fall of 2017, he be-
gan graduate study at WuhanUniversity under the directionof Prof. Qianghui Zhou. His re-
search focuses on syntheticmethodology developmentsand asymmetric catalysis.
Siwei Zhou has studied at Wu-han University, where he will re-ceive his B.Sc. degree in 2020.
Currently, he is undertaking hisgraduation project under theguidance of Prof. Qianghui
Zhou. His research interest fo-cuses on the synthesis of biolog-ical active molecules.
Hong-Gang Cheng receivedhis Ph.D. from Central ChinaNormal University in 2014, un-der the supervision of Prof.Wen-Jing Xiao. Then, he con-ducted his postdoctoral re-search at the University of
Tokyo with Prof. Shū Kobayashi,at Wuhan University with Prof.Qianghui Zhou, and at RWTHAachen University with Prof.Franziska Schoenebeck. He iscurrently an associate professorat Wuhan University. His re-
search interests include the de-velopment of new syntheticmethodologies and the synthe-sis of bioactive natural prod-ucts.
Qianghui Zhou received hisB.S. degree from Peking Univer-sity in 2005. He pursued gradu-ate study under the guidance ofProf. Dawei Ma at Shanghai In-stitute of Organic Chemistryand earned his Ph.D. in 2010.
He then took up a postdoctoralposition in the lab of Prof. Phil S.Baran at The Scripps ResearchInstitute. In June 2015, he be-gan his independent career inthe College of Chemistry andMolecular Sciences of Wuhan
University. His lab currently fo-cuses on developing novelmethodologies for the synthesisof biologically important mole-cules.
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alkylation of aryl iodides via Pd/NBE cooperative catalysis,using alkyl tosylates as the new generation alkylating re-agent (Scheme 1c).
Initially, our efforts commenced with a model reactionusing readily available 1-iodonaphthalene (1a), n-butyl to-sylate (2a), and tert-butyl acrylate (3a) as the reactants (Ta-ble 1). After extensive survey of the reaction parameters,22
the optimal conditions were identified to be: Pd2(dba)3 asthe catalyst (2.5 mol%), XPhos23 as the ligand (2.5 mol%), theinexpensive NBE derivative 5-norbornene-2-carbonitrile asthe mediator (N1, 20 mol%), Cs2CO3 as the base (2.5 equiv),and CH3CN as the solvent, where the desired product 4awas obtained in 98% yield at 80 °C under argon (entry 1). Aseries of control experiments were subsequently conducted
Scheme 1 Previous work, and alkyl tosylates as alkylating reagents in the Catellani reaction
I+ +
T
H Eterminatingreagent
Pd/NBE cooperative catalysis
"Catellani reaction"
alkyl OTs
Pd2(dba)3/XPhos+ R3
R3
R2
R2OTs
1 2 3 4
+
R1R1
broad substrate scopecatalytic amounts of NBE-CN as mediator
(a) The electrophilic reagents employed in the Catellani reaction
(c) This work: Alkyl tosylate as alkylating reagent
easily accessible starting materials
electrophilicreagent
E
alkyl/aryl NR4
R3
OBzX
since 1997/2001 since 2013
R5
since 2015
N
R2
since 2010
X
R6
X = O, NPGsince 2018
Me3R7-R7Me3
X
R7 = Si, Ge, Snsince 2018
X
O
CH3OTsCD3OTs
PO(OCH3)3
Cooperative Pd/NBE catalysis T
CH3/CD3
T−Y
(b) Dual-tasked methylation enabled by palladium/NBE catalysis
alkene, alkyne, Ar-BpinB2pin2, Zn(CN)2, HCO2Na
R8-SR9
since 2019 This work
I
H
R1
I
H
R1
R1
R1
T−Y
++
CN
[NBE](±)
Table 1 Optimization of Reaction Conditionsa
Entry Change from the standard conditions Yield (%)b
1 no change 98 (86)c
2 no Pd2(dba)3 0
3 no N1 0
4 no XPhos 76
5 N2 instead of N1 45
6 K2CO3 instead of Cs2CO3 41
7 toluene instead of CH3CN 11
8 1a (1.0 equiv) and 3a (1.2 equiv) instead of 1a (1.2 equiv) and 3a (1.0 equiv) 63
a All reactions were performed on a 0.1 mmol scale.b GC yield with biphenyl as an internal standard.c Isolated yield in parentheses.
N1 (20 mol%)Cs2CO3 (2.5 equiv)
CH3CN (0.2 M), 80 °C, 15 h
Pd2(dba)3 (2.5 mol%)XPhos (2.5 mol%) CO2tBu
nBu
+
I
+ CO2tBu
1a(1.2 equiv)
2a(2.0 equiv)
3a(1.0 equiv)
4a
"Standard Conditions"
nBu OTs
XPhos iPr
iPr
iPr
PCy2N2CNN1(±)
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to investigate the role of each component. In the absence ofeither Pd catalyst or mediator, no desired product 4a wasobserved (entries 2, 3). In contrast, product 4a can be pro-duced in the absence of phosphine ligand, albeit in a loweryield (entry 4). On the other hand, using simple NBE (N2)resulted in a significantly lower yield (entry 5). The use ofpotassium carbonate instead of cesium carbonate as thebase dramatically decreased the yield (entry 6). The polari-ty of the reaction solvent is also important, since theswitching of CH3CN to toluene led to sluggish results (entry7). Notably, when aryl iodide 1a was used as the limitingreagent, dramatically lower yield was observed (entry 8).
With the above optimal conditions in hand, we firstlyexamined the scope of aryl iodides 1, with n-butyl tosylate(2a) and tert-butyl acrylate (3a) as the reaction partners. Asshown in Scheme 2a, bicyclic aryl iodides (4a,b), as well asones bearing a methyl (4c, 4h–o), ethyl (4d), trifluorometh-yl (4f), phenyl (4g), and even sterically hindered isopropylgroup (4e) at the ortho position, were suitable substrates,affording the corresponding products in 42–91% yield. Thisreaction exhibited high chemoselectivity, as a variety offunctional groups were well tolerated, including bromide(4b and 4l),24 fluoride (4i and 4k), methyl ester (4m and
4p), amide (4n), nitro (4o), benzyloxy (4p and 4q), and me-thoxy (4r), providing opportunities for further diversifica-tions. Notably, densely functionalized aryl iodides (4p and4q) and heteroaryl iodide (4r) also reacted well to afford thedesired products in moderate yields.
Then, the scope of olefins 3 was explored. As shown inScheme 2b, an array of monosubstituted olefins with elec-tron-withdrawing groups, such as acrylates (4a′,b′), methylvinyl ketone (4c′), and acrylaldehyde (4d′), as well as theWeinreb amide derivative of acrylic acid (4e′), are suitablesubstrates to provide the corresponding products in moder-ate to excellent yields (42–92%). Notably, acrylonitrile af-forded the product 4f′ as a mixture of geometrical isomersin 79% yield (Z/E = 1.6:1). Interestingly, simple styrene and4-nitrostyrene were also competent substrates to generateproducts 4g′ and 4h′ in 54% and 74% yield, respectively.
We subsequently examined the scope of alkyl tosylates2 (Scheme 3). The reactions with tosylates containing apure aliphatic chain gave the desired products 4a′′–c′′ in ex-cellent yields (90–95%). Other tosylates with various func-tional groups, including ester (4d′′), trifluoromethyl (4e′′),protected amino group (4f′′), phenyl (4g′′), and naphthyl(4h′′), afforded the corresponding products 4d′′–h′′ in good
Scheme 2 Substrate scope with respect to aryl iodides 1 and olefins 3. All reactions were performed on a 0.2 mmol scale. Isolated yields are reported.
R1 4c: R1 = Me, 75%4d: R1 = Et, 80%4e: R1 = iPr, 76%4f: R1 = CF3, 56%4g: R1 = Ph, 77%
4j: R1 = Me, 56%4k: R1 = F, 75%4l: R1 = Br, 79%4m: R1 = CO2Me, 87%4n: R1 = CONHMe, 91%4o: R1 = NO2, 43%
Me
N
4r: 53%
MeO
4q: 53%
Br
4b: 82%
CO2tBu
nBu
CO2tBu
nBu
CO2tBu
nBu
CO2tBu
nBu
BnO
O
O
O
MeMe
CO2tBu
nBu
CO2tBu
nBu
N1 (20 mol%)Cs2CO3 (2.5 equiv)
CH3CN (0.2 M), 80 °C, 15 h
Pd2(dba)3 (2.5 mol%)XPhos (2.5 mol%) EWG
nBu
+ + EWG
1(1.2 equiv)
2a(2.0 equiv)
3(1.0 equiv)
4
nBu OTsR1
IR1
4a: 86%
R1 4h: R1 = Me, 75%4i: R1 = F, 81%
MeCO2tBu
nBuR1
BnOMeO2C
BnO
4p: 42%
CO2tBu
nBu
(a) Reaction scope of aryl iodides 1
(b) Reaction scope of olefins 3
Ph
nBu
4f': 79% (Z/E = 1.6:1)
4e': 67%
CN
nBu
4a': 87% 4b': 92%
CO2Et
nBu
CO2Bn
nBu
4c': 81%
nBu
Me
O
4g': 54%
4d': 42%
nBu
H
O
nBu
4h': 74%
NO2
nBu
N
OOMe
Me
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to excellent yields. Interestingly, in the case of 3-bromo-propyl tosylate, a mixture of inseparable bromo/iodo-substituted product 4i′′ was obtained in 56% yield (ratio ofBr/I = 1:1.3), which may be attributed to partial iodo/bromoexchange during the reaction. Moreover, cyclopentylmethyl(4j′′), cyclobutylmethyl (4k′′), and benzyl (4l′′) tosylates
were also tolerated. It is noteworthy that the alkyl benzene-sulfonate, alkyl 4-nitrobenzenesulfonate,25 and alkylmesylate could also participate in the reaction smoothly toprovide product 4h′′ in 74–84% yield. However, secondaryalkyl tosylates furnished the corresponding products invery low yield (4m′′ and 4n′′).
Scheme 3 Substrate scope with respect to tosylates 2. All reactions were performed on a 0.2 mmol scale. Isolated yields are reported. a 2-(Naphthalen-1-yl)ethyl benzenesulfonate was applied. b 2-(Naphthalen-1-yl)ethyl 4-nitrobenzenesulfonate was applied. c 2-(Naphthalen-1-yl)ethyl mesylate was ap-plied. d Pd2(dba)3 (5 mol%), XPhos (5 mol%), and N1 (50 mol%) were applied.
CO2tBu
4n'': trace
N1 (20 mol%)Cs2CO3 (2.5 equiv)
CH3CN (0.2 M), 80 °C, 15 h
Pd2(dba)3 (2.5 mol%)XPhos (2.5 mol%)
+ + CO2tBu
1a(1.2 equiv)
2(2.0 equiv)
3a(1.0 equiv)
4a''–n''
R2 OTs
I
4a'': 90%
CO2tBu
4l'': 41%
CO2tBu
4g'': 97%
CO2tBu
Ph
4h'': 85%, (84%)a, (76%)b, (74%)c
1-Naphthyl
4f'': 82%
4c'': 95%
CO2tBu
4d'': 92%
CO2tBu
CO2Et( )3
4j'': 85%
CO2tBu
4k'': 84%
CO2tBu
4e'': 89%
CO2tBu
CF3
MeMe
4b'': 93%
CO2tBu
Me( )
9Me
CO2tBu
R2
CO2tBu
NPhth
4i'': 56%(Br/I = 1:1.3)
CO2tBu
Br/I
CO2tBu
CO2tBu
Me
Me
4m'': 14%d
Scheme 4 Synthetic applications and scale-up experiment
TsOFG or
CO2Et
m
CHO
m
CO2Et CHO
6a: 87% 6d: 71%
CHO
6c: 43%6b: 87%
CO2Et
6e: 86%
CHO
N1 (50 mol%)Cs2CO3 or K2CO3 (2.5 equiv)CH3CN (0.2 M), 80 °C, 15 h
Pd2(dba)3 (5 mol%)XPhos (5 mol%)
+
6a,b
I
5a,b: FG = CO2Et5c–e: FG = CH2OH
6c–e
(A)
1a(1.2 equiv)
( ) ( )
( )m
(B)
EtO2C OTsN1 (20 mol%)
Cs2CO3 (2.5 equiv)CH3CN (0.2 M), 80 °C, 15 h
Pd2(dba)3 (2.5 mol%)XPhos (2.5 mol%)
+ CO2tBuCO2tBu
4d''1.44 g, 91%
I
+CO2Et
1a(4.8 mmol)
2e (8.0 mmol)
3a (4.0 mmol)
( )5
( )5
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To illustrate the synthetic utility of this protocol, an an-nulation process was explored by incorporation of an aryliodide 1 and an olefin-containing tosylate 5 (Scheme 4A). Itwas found that 1a reacted with the bifunctional olefinic es-ter-containing tosylates 5a and 5b to afford the benzo-fused products 6a and 6b, both in 87% yield. When olefinicalcohol-containing tosylates 5c–e were employed, a consec-utive intermolecular Catellani-type C–H alkylation followedby an intramolecular redox-relay Heck termination oc-curred, providing the corresponding five-, six-, and seven-membered carbocycles 6c–e with a diversifiable carbonylfunctionality in 43–86% yield. The practicality of this proto-col was investigated by running the reaction on a largerscale (3a, 4.0 mmol), which led to an intriguing gram-scalepreparation of product 4d′′ (1.44 g, 91% yield) (Scheme 4B).
In summary, we have developed a cooperative catalyticsystem involving a Pd/XPhos complex and 5-norbornene-2-carbonitrile that enables the use of alkyl tosylates as al-kylating reagents in the Catellani reaction, providing a valu-able complement to state-of-the-art transformations. Thismild, scalable protocol is compatible with a wide range ofreadily available functionalized aryl iodides and alkyl to-sylates, as well as terminating olefins. The inexpensive re-agent 5-norbornene-2-carbonitrile acts as a catalytic medi-ator for the process, and only 20 mol% is required to achievesatisfactory results. Further studies on the application of al-kyl tosylates as alkylating reagents in other Catellani-typereactions are currently ongoing in our laboratory.
All reactions dealing with air- or moisture-sensitive compounds wereperformed by standard Schlenk techniques in oven-dried reactionvessels under argon atmosphere. Unless otherwise noted, all solventswere dried with a JC Meyer Solvent Drying System. Most reagentswere purchased from commercial sources and used without furtherpurification, unless otherwise stated. Reactions were monitored byTLC carried out on 0.2 mm commercial silica gel plates, using UV lightas the visualizing agent or a basic solution of KMnO4 or an acidic solu-tion of p-anisaldehyde and heat as the developing agent. 1H NMR and13C NMR spectra were recorded with a Bruker DMX 400 spectrometer(400 MHz; 1H at 400 MHz, 13C at 100 MHz). Chemical shifts are re-ported in parts per million (ppm, ) downfield from TMS ( = 0.00ppm) and were referenced to residual solvent [CDCl3, = 7.26 ppm(1H) and 77.16 ppm (13C)]. All 19F chemical shifts were not referenced.Coupling constants are reported in hertz (Hz). Data for 1H NMR spec-tra are reported as follows: chemical shift (ppm, referenced to pro-tium), multiplicity (standard abbreviations), coupling constant (Hz),and integration. Gas chromatography was recorded with an Agilent7890 instrument with biphenyl as internal standard. High-resolutionmass spectra (HRMS) were recorded with a Bruker Compact TOF massspectrometer system.
Compounds 4; General ProcedureA 25-mL oven-dried Schlenk tube equipped with a magnetic stir barwas charged with Pd2(dba)3 (4.6 mg, 0.005 mmol, 0.025 equiv), XPhos(2.4 mg, 0.005 mmol, 0.025 equiv), Cs2CO3 (162.9 mg, 0.5 mmol, 2.5equiv), and anhydrous CH3CN (1.0 mL). After stirring for about 15 min
at r.t. under argon, aryl iodide 1 (0.24 mmol, 1.2 equiv), alkyl tosylate2 (0.4 mmol, 2.0 equiv), olefin 3 (0.2 mmol, 1.0 equiv), and 5-nor-bornene-2-carbonitrile (4.8 mg, 0.04 mmol, 0.2 equiv) were added,then the mixture was heated to 80 °C and stirred for 15 h. After com-pletion of the reaction (monitored by TLC), the mixture was cooled tor.t., filtered through a thin pad of Celite, eluting with EtOAc (10 mL),and the combined filtrate was concentrated in vacuo. The residue wasdirectly purified by column chromatography on silica gel or purifiedby PTLC to give the desired product.
tert-Butyl (E)-3-(2-Butylnaphthalen-1-yl)acrylate (4a)Yield: 53.4 mg (86%); colorless oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.11–8.05 (m, 2 H), 7.82–7.80 (m, 1 H),7.75 (d, J = 8.4 Hz, 1 H), 7.51–7.41 (m, 2 H), 7.35 (d, J = 8.5 Hz, 1 H),6.15 (d, J = 16.3 Hz, 1 H), 2.83–2.79 (m, 2 H), 1.65–1.61 (m, 2 H), 1.59(s, 9 H), 1.44–1.37 (m, 2 H), 0.95 (t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 166.02, 141.66, 138.94, 132.20,131.55, 130.91, 128.51, 128.31, 128.00, 127.59, 126.45, 125.30,125.24, 80.85, 33.72, 33.56, 28.39, 22.71, 14.09.HRMS (ESI): m/z calcd for C21H26NaO2 [M + Na+]: 333.1825; found:333.1828.
tert-Butyl (E)-3-(4-Bromo-2-butylnaphthalen-1-yl)acrylate (4b)Yield: 64.0 mg (82%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.23–8.21 (m, 1 H), 8.04–7.98 (m, 2 H),7.68 (s, 1 H), 7.56–7.52 (m, 2 H), 6.11 (d, J = 16.3 Hz, 1 H), 2.78–2.74(m, 2 H), 1.64–1.61 (m, 2 H), 1.58 (s, 9 H), 1.44–1.35 (m, 2 H), 0.95 (t,J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 165.72, 140.90, 139.47, 132.77,131.83, 131.13, 130.62, 128.22, 127.51, 127.20, 126.68, 125.71,123.34, 81.07, 33.39, 28.36, 22.66, 14.03.HRMS (ESI): m/z calcd for C21H25BrNaO2 [M + Na+]: 411.0930; found:411.0936.
tert-Butyl (E)-3-(2-Butyl-6-methylphenyl)acrylate (4c)Yield: 41.0 mg (75%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.77 (d, J = 16.4 Hz, 1 H), 7.16–7.12 (m,1 H), 7.06–7.05 (m, 2 H), 5.96 (d, J = 16.3 Hz, 1 H), 2.65–2.61 (m, 2 H),2.34 (s, 3 H), 1.55 (s, 9 H), 1.52–1.49 (m, 2 H), 1.40–1.34 (m, 2 H), 0.92(t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 166.20, 142.45, 141.62, 136.39,134.06, 128.23, 128.09, 127.16, 125.92, 80.66, 33.57, 33.39, 28.35,22.69, 21.46, 14.05.HRMS (ESI): m/z calcd for C18H26NaO2 [M + Na+]: 297.1825; found:297.1829.
tert-Butyl (E)-3-(2-Butyl-6-ethylphenyl)acrylate (4d)Yield: 46.0 mg (80%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.78 (d, J = 16.3 Hz, 1 H), 7.21–7.17 (m,1 H), 7.10–7.05 (m, 2 H), 5.94 (d, J = 16.3 Hz, 1 H), 2.67–2.60 (m, 4 H),1.55 (s, 9 H), 1.53–1.49 (m, 2 H), 1.39–1.30 (m, 2 H), 1.18 (t, J = 7.5 Hz,3 H), 0.92 (t, J = 7.3 Hz, 3 H).
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13C NMR (100 MHz, CDCl3): = 166.05, 142.60, 142.40, 141.21,133.88, 128.16, 127.01, 126.20, 126.01, 80.68, 33.55, 33.41, 28.35,26.92, 22.71, 15.49, 14.04.HRMS (ESI): m/z calcd for C19H28NaO2 [M + Na+]: 311.1982; found:311.1985.
tert-Butyl (E)-3-(2-Butyl-6-isopropylphenyl)acrylate (4e)Yield: 45.8 mg (76%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.80 (d, J = 16.2 Hz, 1 H), 7.24–7.20 (m,1 H), 7.17–7.15 (m, 1 H), 7.06–7.04 (m, 1 H), 5.88 (d, J = 16.3 Hz, 1 H),3.16–3.12 (m, 1 H), 2.61–2.57 (m, 2 H), 1.55 (s, 9 H), 1.53–1.47 (m, 2H), 1.38–1.33 (m, 2 H), 1.19 (d, J = 6.8 Hz, 6 H), 0.91 (t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 165.95, 146.87, 143.00, 140.80,133.57, 128.19, 126.75, 126.32, 122.95, 80.73, 33.69, 33.36, 30.05,28.36, 24.08, 22.75, 14.03.HRMS (ESI): m/z calcd for C20H30NaO2 [M + Na+]: 325.2138; found:325.2144.
tert-Butyl (E)-3-(2-Butyl-6-(trifluoromethyl)phenyl)acrylate (4f)Yield: 37.0 mg (56%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.80–7.74 (m, 1 H), 7.53–7.51 (m, 1 H),7.41–7.39 (m, 1 H), 7.35–7.31 (m, 1 H), 5.94 (d, J = 16.2 Hz, 1 H), 2.66–2.62 (m, 2 H), 1.54 (s, 9 H), 1.53–1.47 (m, 2 H), 1.38–1.30 (m, 2 H),0.92 (t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 165.27, 142.53, 139.79, 133.98 (q, J =2.0 Hz), 132.88, 128.67 (q, J = 29.5 Hz), 127.97 (q, J = 2.2 Hz), 127.85,124.17 (q, J = 273.8 Hz), 123.67 (q, J = 5.6 Hz), 81.00, 33.11, 33.07,28.29, 22.58, 13.96.19F NMR (377 MHz, CDCl3): = –58.13.HRMS (ESI): m/z calcd for C18H23F3NaO2 [M + Na+]: 351.1542; found:351.1543.
tert-Butyl (E)-3-(3-Butyl-[1,1′-biphenyl]-2-yl)acrylate (4g)Yield: 52.0 mg (77%); light yellow oil.Rf = 0.5 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.62 (d, J = 16.4 Hz, 1 H), 7.39–7.20 (m,7 H), 7.18–7.15 (m, 1 H), 5.59 (d, J = 16.3 Hz, 1 H), 2.79–2.68 (m, 2 H),1.63–1.57 (m, 2 H), 1.43 (s, 9 H), 1.42–1.36 (m, 2 H), 0.94 (t, J = 7.3 Hz,3 H).13C NMR (100 MHz, CDCl3): = 166.03, 142.29, 142.20, 142.05,141.65, 132.81, 129.93, 128.87, 128.30, 128.25, 128.12, 127.07,126.47, 80.32, 33.73, 33.60, 28.25, 22.77, 14.08.HRMS (ESI): m/z calcd for C23H28NaO2 [M + Na+]: 359.1982; found:359.1982.
tert-Butyl (E)-3-(6-Butyl-2,3-dimethylphenyl)acrylate (4h)Yield: 43.3 mg (75%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.77 (d, J = 16.3 Hz, 1 H), 7.05 (d, J = 7.7Hz, 1 H), 6.96 (d, J = 7.7 Hz, 1 H), 5.88 (d, J = 16.3 Hz, 1 H), 2.60–2.56(m, 2 H), 2.26 (s, 3 H), 2.22 (s, 3 H), 1.54 (s, 9 H), 1.53–1.46 (m, 2 H),1.38–1.30 (m, 2 H), 0.91 (t, J = 7.3 Hz, 3 H).
13C NMR (100 MHz, CDCl3): = 166.12, 143.53, 138.78, 134.59,134.56, 134.51, 129.60, 126.57, 126.28, 80.64, 33.43, 33.41, 28.36,22.69, 20.57, 17.36, 14.04.HRMS (ESI): m/z calcd for C19H28NaO2 [M + Na+]: 311.1982; found:311.1989.
tert-Butyl (E)-3-(6-Butyl-3-fluoro-2-methylphenyl)acrylate (4i)Yield: 47.1 mg (81%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.69 (d, J = 16.3 Hz, 1 H), 7.01–6.97 (m,1 H), 6.93–6.89 (m, 1 H), 5.93 (d, J = 16.3 Hz, 1 H), 2.59–2.55 (m, 2 H),2.23 (d, J = 2.4 Hz, 3 H), 1.55 (s, 9 H), 1.52–1.45 (m, 2 H), 1.37–1.31 (m,2 H), 0.91 (t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 165.83, 159.73 (d, J = 241.6 Hz),141.42 (d, J = 2.9 Hz), 136.93 (d, J = 3.6 Hz), 135.95 (d, J = 4.3 Hz),127.71 (d, J = 8.6 Hz), 126.94, 123.08 (d, J = 16.5 Hz), 114.61 (d, J = 23.0Hz), 80.89, 33.34, 33.08, 28.32, 22.57, 14.02, 12.60 (d, J = 5.5 Hz).19F NMR (377 MHz, CDCl3): = –118.90.HRMS (ESI): m/z calcd for C18H25FNaO2 [M + Na+]: 315.1731; found:315.1740.
tert-Butyl (E)-3-(2-Butyl-4,6-dimethylphenyl)acrylate (4j)Yield: 32.0 mg (56%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.76 (d, J = 16.4 Hz, 1 H), 6.88 (s, 2 H),5.95 (d, J = 16.3 Hz, 1 H), 2.63–2.59 (m, 2 H), 2.32 (s, 3 H), 2.29 (s, 3 H),1.55 (s, 9 H), 1.54–1.48 (m, 2 H), 1.40–1.34 (m, 2 H), 0.93 (t, J = 7.3 Hz,3 H).13C NMR (100 MHz, CDCl3): = 166.41, 142.37, 141.87, 137.98,136.53, 130.96, 129.23, 128.07, 125.26, 80.54, 33.62, 33.54, 28.37,22.76, 21.51, 21.26, 14.07.HRMS (ESI): m/z calcd for C19H28NaO2 [M + Na+]: 311.1982; found:311.1986.
tert-Butyl (E)-3-(2-Butyl-4-fluoro-6-methylphenyl)acrylate (4k)Yield: 44.0 mg (75%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.68 (d, J = 16.3 Hz, 1 H), 6.76 (d, J = 9.5Hz, 2 H), 5.92 (d, J = 16.3 Hz, 1 H), 2.63–2.59 (m, 2 H), 2.33 (s, 3 H),1.54 (s, 9 H), 1.53–1.48 (m, 2 H), 1.48–1.31 (m, 2 H), 0.92 (t, J = 7.3 Hz,3 H).13C NMR (100 MHz, CDCl3): = 166.08, 162.15 (d, J = 246.9 Hz),144.25 (d, J = 7.7 Hz), 141.46, 139.00 (d, J = 8.1 Hz), 129.95 (d, J = 3.0Hz), 126.08, 114.91 (d, J = 21.0 Hz), 113.70 (d, J = 20.7 Hz), 80.75,33.61, 33.60 (d, J = 1.8 Hz), 28.34, 22.58, 21.61 (d, J = 1.7 Hz), 14.02.19F NMR (377 MHz, CDCl3): = –114.58.HRMS (ESI): m/z calcd for C18H25FNaO2 [M + Na+]: 315.1731; found:315.1745.
tert-Butyl (E)-3-(4-Bromo-2-butyl-6-methylphenyl)acrylate (4l)Yield: 55.7 mg (79%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.65 (d, J = 16.3 Hz, 1 H), 7.20 (s, 2 H),5.94 (d, J = 16.3 Hz, 1 H), 2.60–2.56 (m, 2 H), 2.30 (s, 3 H), 1.54 (s, 9 H),1.52–1.46 (m, 2 H), 1.39–1.31 (m, 2 H), 0.92 (t, J = 7.3 Hz, 3 H).
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13C NMR (100 MHz, CDCl3): = 165.89, 143.69, 141.31, 138.51,133.04, 130.95, 129.94, 126.48, 122.01, 80.88, 33.36, 33.11, 28.32,22.61, 21.23, 14.00.HRMS (ESI): m/z calcd for C18H25BrNaO2 [M + Na+]: 375.0930; found:375.0923.
Methyl 4-((E)-3-tert-Butoxy-3-oxoprop-1-en-1-yl)-3-butyl-5-methylbenzoate (4m)Yield: 57.6 mg (87%); light yellow oil.Rf = 0.3 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.74–7.70 (m, 3 H), 5.97 (d, J = 16.4 Hz,1 H), 3.90 (s, 3 H), 2.67–2.63 (m, 2 H), 2.35 (s, 3 H), 1.54 (s, 9 H), 1.52–1.49 (m, 2 H), 1.38–1.32 (m, 2 H), 0.91 (t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 167.19, 165.70, 141.78, 141.54,138.92, 136.59, 129.29, 129.05, 128.10, 126.98, 80.97, 52.23, 33.45,33.17, 28.30, 22.64, 21.33, 14.00.HRMS (ESI): m/z calcd for C20H28NaO4 [M + Na+]: 355.1880; found:355.1883.
tert-Butyl (E)-3-(2-Butyl-6-methyl-4-(methylcarbamoyl)phe-nyl)acrylate (4n)Yield: 60.0 mg (91%); colorless oil.Rf = 0.3 (50% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.71 (d, J = 16.4 Hz, 1 H), 7.43 (s, 2 H),6.22 (s, 1 H), 5.96 (d, J = 16.3 Hz, 1 H), 3.00 (d, J = 4.8 Hz, 3 H), 2.68–2.62 (m, 2 H), 2.34 (s, 3 H), 1.54 (s, 9 H), 1.52–1.45 (m, 2 H), 1.37–1.32(m, 2 H), 0.91 (t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 168.23, 165.81, 142.05, 141.53,137.27, 136.82, 133.91, 126.81, 126.48, 125.53, 80.96, 33.57, 33.24,28.32, 26.97, 22.67, 21.45, 14.01.HRMS (ESI): m/z calcd for C20H29NNaO3 [M + Na+]: 354.2040; found:354.2047.
tert-Butyl (E)-3-(2-Butyl-6-methyl-4-nitrophenyl)acrylate (4o)Yield: 27.0 mg (43%); light yellow oil.Rf = 0.5 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.91 (s, 2 H), 7.67 (d, J = 16.4 Hz, 1 H),5.99 (d, J = 16.4 Hz, 1 H), 2.70–2.66 (m, 2 H), 2.40 (s, 3 H), 1.63–1.55(m, 2 H), 1.53 (s, 9 H), 1.41–1.32 (m, 2 H), 0.93 (t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 165.23, 147.09, 143.16, 141.09,140.36, 138.07, 128.02, 122.65, 121.65, 81.36, 33.45, 32.81, 28.28,22.54, 21.44, 13.96.HRMS (ESI): m/z calcd for C18H25NNaO4 [M + Na+]: 342.1676; found:342.1686.
Methyl 2,6-Bis(benzyloxy)-3-((E)-3-tert-butoxy-3-oxoprop-1-en-1-yl)-4-butylbenzoate (4p)Yield: 44.0 mg (42%); light yellow solid; mp 80–85 °C.Rf = 0.3 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.70 (d, J = 16.2 Hz, 1 H), 7.44–7.32 (m,10 H), 6.63 (s, 1 H), 6.59 (d, J = 16.1 Hz, 1 H), 5.15 (s, 2 H), 4.85 (s, 2 H),3.86 (s, 3 H), 2.72–2.68 (m, 2 H), 1.57–1.48 (m, 11 H), 1.37–1.31 (m, 2H), 0.92 (t, J = 7.3 Hz, 3 H).
13C NMR (100 MHz, CDCl3): = 167.02, 166.74, 156.24, 156.19,146.97, 136.59, 136.47, 136.42, 128.85, 128.67, 128.56, 128.40,128.07, 127.02, 124.72, 120.61, 118.01, 110.28, 80.32, 76.50, 70.50,52.62, 34.21, 33.29, 28.34, 22.52, 14.05.HRMS (ESI): m/z calcd for C33H38NaO6 [M + Na+]: 553.2561; found:553.2575.
tert-Butyl (E)-3-(5-(Benzyloxy)-7-butyl-2,2-dimethyl-4-oxo-4H-benzo[d][1,3]dioxin-6-yl)acrylate (4q)Yield: 49.0 mg (53%); light yellow oil.Rf = 0.4 (10% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.61 (d, J = 16.2 Hz, 1 H), 7.53–7.51 (m,2 H), 7.38–7.32 (m, 3 H), 6.64 (s, 1 H), 6.52 (d, J = 16.2 Hz, 1 H), 4.94 (s,2 H), 2.71–2.67 (m, 2 H), 1.70 (s, 6 H), 1.58–1.54 (m, 2 H), 1.52 (s, 9 H),1.44–1.36 (m, 2 H), 0.94 (t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 166.68, 159.69, 158.05, 157.02,152.62, 136.14, 135.90, 129.64, 128.56, 128.53, 126.32, 123.77,113.84, 106.30, 105.66, 80.49, 76.35, 34.20, 32.50, 28.32, 25.80, 22.61,14.02.HRMS (ESI): m/z calcd for C28H34NaO6 [M + Na+]: 489.2248; found:489.2249.
tert-Butyl (E)-3-(4-Butyl-2-methoxypyridin-3-yl)acrylate (4r)Yield: 30.0 mg (53%); light yellow oil.Rf = 0.4 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.98 (d, J = 5.2 Hz, 1 H), 7.75 (d, J = 16.0Hz, 1 H), 6.75 (d, J = 5.2 Hz, 1 H), 6.70 (d, J = 16.0 Hz, 1 H), 4.00 (s, 3 H),2.75–2.71 (m, 2 H), 1.59–1.54 (m, 2 H), 1.53 (s, 9 H), 1.43–1.32 (m, 2H), 0.93 (t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 167.31, 162.74, 154.20, 146.33,135.30, 124.95, 118.89, 116.29, 80.48, 53.81, 32.93, 32.81, 28.36,22.66, 14.01.HRMS (ESI): m/z calcd for C17H25NNaO3 [M + Na+]: 314.1727; found:314.1724.
Ethyl (E)-3-(2-Butylnaphthalen-1-yl)acrylate (4a′)Yield: 49.3 mg (87%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.20 (d, J = 16.3 Hz, 1 H), 8.05 (d, J = 7.9Hz, 1 H), 7.83–7.81 (m, 1 H), 7.77 (d, J = 8.4 Hz, 1 H), 7.51–7.43 (m, 2H), 7.36 (d, J = 8.4 Hz, 1 H), 6.24 (d, J = 16.3 Hz, 1 H), 4.37–4.32 (m, 2H), 2.83–2.79 (m, 2 H), 1.64–1.59 (m, 2 H), 1.43–1.37 (m, 5 H), 0.95 (t,J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 166.70, 142.86, 139.02, 132.19,131.49, 130.69, 128.70, 128.35, 128.00, 126.54, 125.81, 125.36,125.11, 60.81, 33.76, 33.61, 22.73, 14.48, 14.10.HRMS (ESI): m/z calcd for C19H22NaO2 [M + Na+]: 305.1512; found:305.1512.
Benzyl (E)-3-(2-Butylnaphthalen-1-yl)acrylate (4b′)Yield: 63.0 mg (92%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.27 (d, J = 16.3 Hz, 1 H), 8.06 (d, J = 8.0Hz, 1 H), 7.82 (d, J = 7.3 Hz, 1 H), 7.77 (d, J = 8.4 Hz, 1 H), 7.51–7.36 (m,8 H), 6.31 (d, J = 16.3 Hz, 1 H), 5.34 (s, 2 H), 2.84–2.80 (m, 2 H), 1.66–1.58 (m, 2 H), 1.50–1.36 (m, 2 H), 0.95 (t, J = 7.3 Hz, 3 H).
© 2020. Thieme. All rights reserved. Synthesis 2020, 52, 834–846
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13C NMR (100 MHz, CDCl3): = 166.49, 143.50, 139.13, 136.10,132.20, 131.44, 130.53, 128.82, 128.75, 128.41, 128.36, 128.00,126.60, 125.38, 125.08, 66.62, 33.80, 33.61, 22.75, 14.10.HRMS (ESI): m/z calcd for C24H24NaO2 [M + Na+]: 367.1669; found:367.1669.
(E)-4-(2-Butylnaphthalen-1-yl)but-3-en-2-one (4c′)Yield: 40.7 mg (81%); light yellow oil.Rf = 0.3 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.06–7.99 (m, 2 H), 7.83 (dd, J = 7.3, 2.0Hz, 1 H), 7.78 (d, J = 8.4 Hz, 1 H), 7.51–7.47 (m, 2 H), 7.37 (d, J = 8.5 Hz,1 H), 6.51 (d, J = 16.5 Hz, 1 H), 2.83–2.79 (m, 2 H), 2.48 (s, 3 H), 1.64–1.58 (m, 2 H), 1.44–1.35 (m, 2 H), 0.94 (t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 198.28, 141.54, 139.15, 134.75,132.25, 131.37, 130.58, 128.93, 128.45, 128.04, 126.65, 125.45,124.97, 33.87, 33.60, 27.88, 22.77, 14.11.HRMS (ESI): m/z calcd for C18H20NaO [M + Na+]: 275.1406; found:275.1411.
(E)-3-(2-Butylnaphthalen-1-yl)acrylaldehyde (4d′)Yield: 20.0 mg (42%); light yellow oil.Rf = 0.4 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 9.89 (d, J = 7.8 Hz, 1 H), 8.06 (d, J = 16.3Hz, 1 H), 8.02–7.99 (m, 1 H), 7.87–7.80 (m, 2 H), 7.53–7.46 (m, 2 H),7.39 (d, J = 8.5 Hz, 1 H), 6.58 (dd, J = 16.2, 7.8 Hz, 1 H), 2.84–2.81 (m, 2H), 1.65–1.60 (m, 2 H), 1.43–1.38 (m, 2 H), 0.95 (t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 193.92, 151.18, 139.44, 136.33,132.28, 131.02, 129.81, 129.71, 128.57, 128.09, 126.97, 125.63,124.70, 33.94, 33.63, 22.79, 14.10.HRMS (ESI): m/z calcd for C17H18NaO [M + Na+]: 261.1250; found:261.1261.
(E)-3-(2-Butylnaphthalen-1-yl)-N-methoxy-N-methylacrylamide (4e′)Yield: 40.0 mg (67%); light yellow oil.Rf = 0.2 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.22 (d, J = 16.1 Hz, 1 H), 8.09–8.06 (m,1 H), 7.83–7.81 (m, 1 H), 7.76 (d, J = 8.4 Hz, 1 H), 7.49–7.42 (m, 2 H),7.37 (d, J = 8.5 Hz, 1 H), 6.81 (d, J = 16.1 Hz, 1 H), 3.71 (s, 3 H), 3.36 (s,3 H), 2.84–2.80 (m, 2 H), 1.66–1.58 (m, 2 H), 1.42–1.37 (m, 2 H), 0.93(t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 166.64, 141.43, 138.86, 132.19,131.76, 131.70, 128.35, 128.29, 128.04, 126.39, 125.32, 125.28,123.59, 62.08, 33.87, 33.77, 32.61, 22.81, 14.19.HRMS (ESI): m/z calcd for C19H23NNaO2 [M + Na+]: 320.1621; found:320.1622.
3-(2-Butylnaphthalen-1-yl)acrylonitrile (4f′)Yield: 37.3 mg (79%); E/Z = 1:1.6; light yellow oil.Rf = 0.5 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): (E-isomer) = 7.96–7.92 (m, 2 H), 7.85–7.79 (m, 2 H), 7.54–7.47 (m, 2 H), 7.36 (d, J = 8.5 Hz, 1 H), 5.73 (d, J =16.9 Hz, 1 H), 2.80–2.76 (m, 2 H), 1.64–1.56 (m, 2 H), 1.45–1.37 (m, 2H), 0.96 (t, J = 7.3 Hz, 3 H); (Z-isomer) = 7.86–7.81 (m, 2 H), 7.77 (d,J = 8.1 Hz, 1 H), 7.73 (d, J = 11.5 Hz, 1 H), 7.54–7.45 (m, 2 H), 7.40 (d,J = 8.5 Hz, 1 H), 5.98 (d, J = 11.5 Hz, 1 H), 2.81–2.77 (m, 2 H), 1.66–1.58(m, 2 H), 1.41–1.35 (m, 2 H), 0.94 (t, J = 7.3 Hz, 3 H).
13C NMR (100 MHz, CDCl3): (E-isomer) = 149.53, 139.23, 132.21,131.04, 129.68, 129.51, 128.59, 127.95, 127.12, 125.70, 124.36,117.81, 104.32, 33.81, 33.67, 22.78, 14.11; (Z-isomer) = 149.68,138.61, 132.00, 130.70, 129.41, 129.26, 128.53, 127.68, 126.79,125.59, 124.53, 116.12, 104.47, 33.68, 33.24, 22.76, 14.11.HRMS (ESI): m/z calcd for C17H17NNa [M + Na+]: 258.1253; found:258.1262 (E-isomer), 258.1255 (Z-isomer).
2-Butyl-((E)-1-styryl)naphthalene (4g′)Yield: 31.0 mg (54%); light yellow oil.Rf = 0.8 (petroleum).1H NMR (400 MHz, CDCl3): = 8.17–8.15 (m, 1 H), 7.82–7.78 (m, 1 H),7.72 (d, J = 8.4 Hz, 1 H), 7.59–7.58 (m, 2 H), 7.50–7.31 (m, 7 H), 6.75(d, J = 16.6 Hz, 1 H), 2.87–2.84 (m, 2 H), 1.68–1.61 (m, 2 H), 1.43–1.34(m, 2 H), 0.92 (t, J = 7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 138.40, 137.59, 135.66, 133.58,132.41, 132.37, 128.89, 128.21, 128.08, 127.86, 127.27, 126.55,125.95, 125.80, 125.02, 33.85, 33.59, 22.82, 14.20.HRMS (ESI): m/z calcd for C22H23 [M + H+]: 287.1794; found:287.1790.
2-Butyl-1-((E)-4-nitrostyryl)naphthalene (4h′)Yield: 49.0 mg (74%); yellow solid; mp 96–100 °C.Rf = 0.4 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.28 (d, J = 8.5 Hz, 2 H), 8.12–8.10 (m, 1H), 7.86–7.84 (m, 1 H), 7.78 (d, J = 8.4 Hz, 1 H), 7.71–7.66 (m, 3 H),7.51–7.45 (m, 2 H), 7.41 (d, J = 8.4 Hz, 1 H), 6.84 (d, J = 16.5 Hz, 1 H),2.88–2.84 (m, 2 H), 1.70–1.62 (m, 2 H), 1.45–1.38 (m, 2 H), 0.94 (t, J =7.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 147.05, 143.82, 138.71, 133.55,132.36, 132.00, 130.80, 128.40, 128.07, 128.05, 126.94, 126.31,125.30, 125.26, 124.33, 33.84, 33.57, 22.77, 14.15.HRMS (ESI): m/z calcd for C22H21NNaO2 [M + Na+]: 354.1465; found:354.1474.
tert-Butyl (E)-3-(2-Hexylnaphthalen-1-yl)acrylate (4a′′)Yield: 60.7 mg (90%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.12–8.05 (m, 2 H), 7.83–7.80 (m, 1 H),7.75 (d, J = 8.4 Hz, 1 H), 7.51–7.43 (m, 2 H), 7.35 (d, J = 8.4 Hz, 1 H),6.15 (d, J = 16.3 Hz, 1 H), 2.82–2.78 (m, 2 H), 1.65–1.61 (m, 2 H), 1.60(s, 9 H), 1.40–1.35 (m, 2 H), 1.34–1.30 (m, 4 H), 0.90 (t, J = 6.3 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 166.00, 141.67, 138.98, 132.20,131.55, 130.90, 128.51, 128.31, 127.99, 127.57, 126.44, 125.29,125.24, 80.82, 34.05, 31.75, 31.38, 29.30, 28.39, 22.72, 14.24.HRMS (ESI): m/z calcd for C23H30NaO2 [M + Na+]: 361.2138; found:361.2141.
tert-Butyl (E)-3-(2-Dodecylnaphthalen-1-yl)acrylate (4b′′)Yield: 78.6 mg (93%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.11–8.05 (m, 2 H), 7.83–7.80 (m, 1 H),7.75 (d, J = 8.4 Hz, 1 H), 7.49–7.44 (m, 2 H), 7.35 (d, J = 8.5 Hz, 1 H),6.15 (d, J = 16.3 Hz, 1 H), 2.82–2.78 (m, 2 H), 1.66–1.62 (m, 2 H), 1.59(s, 9 H), 1.36–1.26 (m, 18 H), 0.88 (t, J = 6.8 Hz, 3 H).
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13C NMR (100 MHz, CDCl3): = 166.01, 141.67, 139.00, 132.20,131.55, 130.90, 128.51, 128.31, 128.00, 127.57, 126.45, 125.30,125.25, 80.83, 34.07, 32.07, 31.46, 29.83, 29.80, 29.79, 29.75, 29.69,29.63, 29.51, 28.40, 22.85, 14.29.HRMS (ESI): m/z calcd for C29H42KO2 [M + K+]: 461.2816; found:461.2817.
tert-Butyl (E)-3-(2-(3-Methylpentyl)naphthalen-1-yl)acrylate (4c′′)Yield: 64.2 mg (95%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.12–8.04 (m, 2 H), 7.82–7.80 (m, 1 H),7.75 (d, J = 8.4 Hz, 1 H), 7.49–7.44 (m, 2 H), 7.35 (d, J = 8.4 Hz, 1 H),6.16 (d, J = 16.3 Hz, 1 H), 2.87–2.72 (m, 2 H), 1.65–1.61 (m, 1 H), 1.61(s, 9 H), 1.46–1.36 (m, 3 H), 1.30–1.17 (m, 1 H), 0.96 (d, J = 6.0 Hz, 3H), 0.90 (t, J = 7.2 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 165.92, 141.57, 139.26, 132.18,131.56, 130.86, 128.57, 128.31, 128.05, 127.64, 126.45, 125.29,125.20, 80.79, 38.42, 34.64, 31.77, 29.36, 28.37, 19.34, 11.52.HRMS (ESI): m/z calcd for C23H30NaO2 [M + Na+]: 361.2138; found:361.2145.
Ethyl 6-(1-((E)-3-tert-Butoxy-3-oxoprop-1-en-1-yl)naphthalen-2-yl)hexanoate (4d′′)Yield: 72.6 mg (92%); light yellow oil.Rf = 0.4 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.10–8.04 (m, 2 H), 7.82–7.74 (m, 1 H),7.75 (d, J = 8.4 Hz, 1 H), 7.49–7.44 (m, 2 H), 7.34 (d, J = 8.4 Hz, 1 H),6.14 (d, J = 16.3 Hz, 1 H), 4.11 (q, J = 7.1 Hz, 2 H), 2.83–2.79 (m, 2 H),2.29 (t, J = 7.5 Hz, 2 H), 1.69–1.63 (m, 4 H), 1.59 (s, 9 H), 1.43–1.38 (m,2 H), 1.24 (t, J = 7.1 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 173.85, 165.94, 141.56, 138.50,132.22, 131.53, 130.96, 128.57, 128.31, 127.86, 127.66, 126.49,125.36, 125.23, 80.89, 60.34, 34.37, 33.81, 30.96, 29.10, 28.38, 24.93,14.37.HRMS (ESI): m/z calcd for C25H32NaO4 [M + Na+]: 419.2193; found:419.2200.
tert-Butyl (E)-3-(2-(4,4,4-Trifluorobutyl)naphthalen-1-yl)acrylate (4e′′)Yield: 65.0 mg (89%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.08–8.04 (m, 2 H), 7.84–7.82 (m, 1 H),7.79 (d, J = 8.5 Hz, 1 H), 7.54–7.45 (m, 2 H), 7.33 (d, J = 8.4 Hz, 1 H),6.14 (d, J = 16.3 Hz, 1 H), 2.90 (t, J = 8.0 Hz, 2 H), 2.16–2.07 (m, 2 H),1.95–1.87 (m, 2 H), 1.59 (s, 9 H).13C NMR (100 MHz, CDCl3): = 165.75, 141.09, 136.56, 132.43,131.53, 131.49, 128.90, 128.37, 128.22, 127.40, 127.19 (q, J = 275 Hz),126.74, 125.73, 125.32, 81.10, 33.41 (q, J = 28.5 Hz), 32.74, 28.35,23.39 (q, J = 3.0 Hz).19F NMR (377 MHz, CDCl3): = –66.08.HRMS (ESI): m/z calcd for C21H23F3NaO2 [M + Na+]: 387.1542; found:387.1546.
tert-Butyl (E)-3-(2-(3-(1,3-Dioxoisoindolin-2-yl)propyl)naphtha-len-1-yl)acrylate (4f′′)Yield: 72.7 mg (82%); light yellow oil.
Rf = 0.2 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.07–8.00 (m, 2 H), 7.81 (dd, J = 5.4, 3.0Hz, 2 H), 7.79–7.76 (m, 1 H), 7.73 (d, J = 8.5 Hz, 1 H), 7.69–7.66 (m, 2H), 7.48–7.41 (m, 2 H), 7.37 (d, J = 8.5 Hz, 1 H), 6.12 (d, J = 16.3 Hz, 1H), 3.76 (t, J = 7.2 Hz, 2 H), 2.91–2.87 (m, 2 H), 2.08–2.01 (m, 2 H), 1.58(s, 9 H).13C NMR (100 MHz, CDCl3): = 168.46, 165.72, 141.21, 136.84,133.98, 132.27, 132.16, 131.54, 131.30, 128.73, 128.30, 128.07,127.40, 126.54, 125.49, 125.24, 123.29, 80.91, 37.97, 31.34, 29.67,28.37.HRMS (ESI): m/z calcd for C28H27NNaO4 [M + Na+]: 464.1832; found:464.1837.
tert-Butyl (E)-3-(2-(3-Phenylpropyl)naphthalen-1-yl)acrylate (4g′′)Yield: 72.6 mg (97%); colorless oil.Rf = 0.5 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.10–8.04 (m, 2 H), 7.81–7.79 (m, 1 H),7.74 (d, J = 8.5 Hz, 1 H), 7.48–7.43 (m, 2 H), 7.33 (d, J = 8.5 Hz, 1 H),7.30–7.26 (m, 2 H), 7.20–7.15 (m, 3 H), 6.13 (d, J = 16.2 Hz, 1 H), 2.86–2.82 (m, 2 H), 2.69 (t, J = 7.8 Hz, 2 H), 2.00–1.92 (m, 2 H), 1.59 (s, 9 H).13C NMR (100 MHz, CDCl3): = 165.90, 142.13, 141.52, 138.27,132.25, 131.56, 131.09, 128.60, 128.49, 128.47, 128.32, 127.83,127.70, 126.50, 125.94, 125.40, 125.23, 80.88, 35.85, 33.71, 32.91,28.40.HRMS (ESI): m/z calcd for C26H28NaO2 [M + Na+]: 395.1982; found:395.1987.
tert-Butyl (E)-3-(2-(2-(Naphthalen-1-yl)ethyl)naphthalen-1-yl)-acrylate (4h′′)Yield: 69.3 mg (85%); white solid; mp 84–87 °C.Rf = 0.4 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.16–8.12 (m, 2 H), 8.09–8.07 (m, 1 H),7.90–7.88 (m, 1 H), 7.87–7.84 (m, 1 H), 7.80 (d, J = 8.5 Hz, 1 H), 7.75(d, J = 8.2 Hz, 1 H), 7.60–7.55 (m, 1 H), 7.55–7.46 (m, 3 H), 7.42 (d, J =8.4 Hz, 1 H), 7.40–7.36 (m, 1 H), 7.30–7.28 (m, 1 H), 6.16 (d, J = 16.3Hz, 1 H), 3.39–3.35 (m, 2 H), 3.27–3.23 (m, 2 H), 1.61 (s, 9 H).13C NMR (100 MHz, CDCl3): = 165.75, 141.43, 137.79, 137.70,133.98, 132.37, 131.86, 131.57, 131.45, 128.95, 128.74, 128.35,128.01, 127.98, 127.04, 126.58, 126.41, 126.21, 125.68, 125.55,125.34, 123.79, 80.92, 35.80, 35.10, 28.41.HRMS (ESI): m/z calcd for C29H28NaO2 [M + Na+]: 431.1982; found:431.1980.
tert-Butyl (E)-3-(2-(3-Bromopropyl)naphthalen-1-yl)acrylate, tert-Butyl (E)-3-(2-(3-Iodopropyl)naphthalen-1-yl)acrylate (4i′′)Yield: 45.0 mg (56%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.11–8.04 (m, 2 H), 7.82 (d, J = 8.7 Hz, 1H), 7.77 (d, J = 8.5 Hz, 1 H), 7.52–7.45 (m, 2 H), 7.37 (d, J = 8.4 Hz, 1 H),6.15 (d, J = 16.3 Hz, 1 H), 3.43 (t, J = 6.4 Hz, 1 H), 3.21 (t, J = 6.7 Hz, 1H), 2.99 (t, J = 7.6 Hz, 1 H), 2.94 (t, J = 7.6 Hz, 1 H), 2.21–2.10 (m, 2 H),1.59 (s, 9 H).13C NMR (100 MHz, CDCl3): = 165.8, 141.2 (141.1), 136.5, 136.4,132.39 (132.38), 131.6 (131.5), 128.8, 128.3, 128.1, 127.8, 126.7,125.6, 125.3, 81.0, 34.7 (34.5), 34.0 (33.3), 32.2, 28.41 (28.39).
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HRMS (ESI): m/z calcd for C20H23BrNaO2 [M + Na+]: 397.0774; found:397.0780; m/z calcd for C20H23INaO2 [M + Na+]: 445.0635; found:445.0629.
tert-Butyl (E)-3-(2-(Cyclopentylmethyl)naphthalen-1-yl)acrylate (4j′′)Yield: 57.5 mg (85%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.12–8.07 (m, 2 H), 7.83–7.80 (m, 1 H),7.75 (d, J = 8.4 Hz, 1 H), 7.49–7.44 (m, 2 H), 7.36 (d, J = 8.4 Hz, 1 H),6.15 (d, J = 16.3 Hz, 1 H), 2.83 (d, J = 7.3 Hz, 2 H), 2.18–2.10 (m, 1 H),1.74–1.64 (m, 4 H), 1.60 (s, 9 H), 1.55–1.50 (m, 2 H), 1.27–1.24 (m, 2H).13C NMR (100 MHz, CDCl3): = 166.03, 141.95, 138.48, 132.24,131.49, 131.12, 128.34, 128.31, 128.30, 127.67, 126.42, 125.34,125.29, 80.83, 41.99, 39.60, 32.66, 28.40, 24.89.HRMS (ESI): m/z calcd for C23H28NaO2 [M + Na+]: 359.1982; found:359.1991.
tert-Butyl (E)-3-(2-(Cyclobutylmethyl)naphthalen-1-yl)acrylate (4k′′)Yield: 54.1 mg (84%); light yellow oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.11–8.06 (m, 2 H), 7.81 (d, J = 8.4 Hz, 1H), 7.74 (d, J = 8.4 Hz, 1 H), 7.49–7.44 (m, 2 H), 7.32 (d, J = 8.5 Hz, 1 H),6.15 (d, J = 16.3 Hz, 1 H), 2.91 (d, J = 7.4 Hz, 2 H), 2.66–2.58 (m, 1 H),2.05–2.00 (m, 2 H), 1.85–1.75 (m, 4 H), 1.60 (s, 9 H).13C NMR (100 MHz, CDCl3): = 166.05, 141.86, 137.41, 132.24,131.53, 131.08, 128.35, 128.30, 127.91, 127.69, 126.42, 125.30, 80.87,40.65, 37.24, 28.69, 28.41, 18.64.HRMS (ESI): m/z calcd for C22H26NaO2 [M + Na+]: 345.1825; found:345.1830.
tert-Butyl (E)-3-(2-Benzylnaphthalen-1-yl)acrylate (4l′′)Yield: 28.2 mg (41%); light yellow oil.Rf = 0.5 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.10–8.05 (m, 2 H), 7.83–7.81 (m, 1 H),7.75 (d, J = 8.5 Hz, 1 H), 7.52–7.44 (m, 2 H), 7.31 (d, J = 8.5 Hz, 1 H),7.26–7.24 (m, 2 H), 7.20–7.18 (m, 1 H), 7.16–7.11 (m, 2 H), 6.09 (d, J =16.3 Hz, 1 H), 4.20 (s, 2 H), 1.56 (s, 9 H).13C NMR (100 MHz, CDCl3): = 165.78, 141.48, 140.74, 136.51,132.42, 131.87, 131.60, 129.03, 128.71, 128.59, 128.54, 128.37,128.00, 126.63, 126.24, 125.69, 125.35, 80.90, 39.86, 28.36.HRMS (ESI): m/z calcd for C24H24NaO2 [M + Na+]: 367.1669; found:367.1666.
tert-Butyl (E)-3-(2-(1-Methylpropyl)naphthalen-1-yl)acrylate (4m′′)Yield: 9.0 mg (14%); colorless oil.Rf = 0.6 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.09 (d, J = 16.3 Hz, 1 H), 8.01–7.99 (m,1 H), 7.83–7.77 (m, 2 H), 7.55–7.40 (m, 3 H), 6.07 (d, J = 16.3 Hz, 1 H),3.13 (q, J = 7.0 Hz, 1 H), 1.72–1.64 (m, 2 H), 1.59 (s, 9 H), 1.27–1.21 (m,3 H), 0.80 (t, J = 7.4 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 165.96, 142.93, 142.22, 132.10,131.49, 131.06, 128.80, 128.25, 128.01, 126.37, 125.57, 125.38,123.93, 80.93, 37.43, 30.86, 28.42, 22.10, 12.39.
HRMS (ESI): m/z calcd for C21H26NaO2 [M + Na+]: 333.1825; found:333.1823.
Compounds 6; General ProcedureA 25-mL oven-dried Schlenk tube equipped with a magnetic stir barwas charged with Pd2(dba)3 (9.2 mg, 0.01 mmol, 0.05 equiv), XPhos(4.8 mg, 0.01 mmol, 0.05 equiv), Cs2CO3 (163 mg, 0.5 mmol, 2.5 equiv)or K2CO3 (69 mg, 0.5 mmol, 2.5 equiv), and anhydrous CH3CN (1.0mL). After stirring for about 15 min at r.t. under argon, aryl iodide 1(0.24 mmol, 1.2 equiv), tosylate 5 (0.2 mmol, 1.0 equiv), and 5-nor-bornene-2-carbonitrile (12 mg, 0.1 mmol, 0.5 equiv) were added,then the mixture was heated to 80 °C and stirred for 15 h. After com-pletion of the reaction (monitored by TLC), the mixture was cooled tor.t., filtered through a thin pad of Celite, eluting with EtOAc (10 mL),and the combined filtrate was concentrated in vacuo. The residue wasdirectly purified by column chromatography on silica gel or purifiedby PTLC to give the desired product.
Ethyl (E)-2-(2,3-Dihydrophenanthren-4(1H)-ylidene)acetate (6a)Base: Cs2CO3; yield: 46.5 mg (87%); yellow oil.Rf = 0.5 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 8.36 (d, J = 8.4 Hz, 1 H), 7.83 (d, J = 7.9Hz, 1 H), 7.73 (d, J = 8.3 Hz, 1 H), 7.52–7.48 (m, 1 H), 7.46–7.42 (m, 1H), 7.27 (d, J = 6.5 Hz, 1 H), 6.25 (t, J = 1.9 Hz, 1 H), 4.25 (q, J = 7.2 Hz, 2H), 3.32 (td, J = 6.9, 1.9 Hz, 2 H), 2.82 (t, J = 6.2 Hz, 2 H), 1.94–1.87 (m,2 H), 1.33 (t, J = 7.1 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 167.09, 154.04, 139.44, 133.39,133.26, 130.27, 128.85, 128.60, 126.64, 126.56, 125.30, 125.14,119.24, 59.95, 30.64, 28.73, 22.36, 14.52.HRMS (ESI): m/z calcd for C18H18NaO2 [M + Na+]: 289.1199; found:289.1198.
Ethyl (E)-2-(7,8,9,10-Tetrahydro-11H-cyclohepta[a]naphthalen-11-ylidene)acetate (6b)Base: Cs2CO3; yield: 48.8 mg (87%); yellow oil.Rf = 0.4 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 7.98–7.95 (m, 1 H), 7.84–7.79 (m, 1 H),7.72 (d, J = 8.3 Hz, 1 H), 7.48–7.41 (m, 2 H), 7.30 (d, J = 8.3 Hz, 1 H),5.83 (s, 1 H), 4.29–4.24 (m, 2 H), 3.84–3.79 (m, 1 H), 3.01–2.94 (m, 1H), 2.81–2.76 (m, 1 H), 2.18–2.13 (m, 1 H), 2.00–1.93 (m, 3 H), 1.59–1.53 (m, 1 H), 1.34 (t, J = 7.1 Hz, 3 H).13C NMR (100 MHz, CDCl3): = 166.60, 161.62, 139.95, 136.43,132.54, 130.09, 128.16, 127.80, 127.63, 126.29, 125.15, 125.11,120.14, 60.10, 35.29, 32.00, 29.57, 27.27, 14.48.HRMS (ESI): m/z calcd for C19H20NaO2 [M + Na+]: 303.1356; found:303.1359.
2-(2,3-Dihydro-1H-cyclopenta[a]naphthalen-1-yl)acetaldehyde (6c)Base: K2CO3; yield: 18.0 mg (43%); brown oil.Rf = 0.5 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 9.87 (s, 1 H), 7.88 (d, J = 8.1 Hz, 1 H),7.78 (d, J = 8.2 Hz, 1 H), 7.72 (d, J = 8.3 Hz, 1 H), 7.50 (t, J = 7.6 Hz, 1 H),7.44 (t, J = 7.2 Hz, 1 H), 7.39 (d, J = 8.3 Hz, 1 H), 4.24–4.18 (m, 1 H),3.22–3.13 (m, 1 H), 3.06–3.04 (m, 1 H), 2.92–2.87 (m, 1 H), 2.69–2.61(m, 1 H), 2.50–2.40 (m, 1 H), 2.06–2.01 (m, 1 H).
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13C NMR (100 MHz, CDCl3): = 202.25, 140.94, 140.61, 133.05,129.52, 129.03, 127.89, 126.46, 124.98, 123.51, 48.36, 37.78, 31.79,31.19.HRMS (ESI): m/z calcd for C15H14NaO [M + Na+]: 233.0937; found:233.0941.
2-(1,2,3,4-Tetrahydrophenanthren-4-yl)acetaldehyde (6d)Base: K2CO3; yield: 32.0 mg (71%); brown oil.Rf = 0.5 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 9.92 (s, 1 H), 7.88 (d, J = 8.4 Hz, 1 H),7.82 (dd, J = 8.1, 1.4 Hz, 1 H), 7.64 (d, J = 8.3 Hz, 1 H), 7.53–7.49 (m, 1H), 7.46–7.42 (m, 1 H), 7.20 (d, J = 8.4 Hz, 1 H), 4.25–4.20 (m, 1 H),2.96–2.93 (m, 2 H), 2.89–2.81 (m, 2 H), 1.99–1.86 (m, 4 H).13C NMR (100 MHz, CDCl3): = 201.87, 134.47, 133.55, 132.72,131.27, 129.08, 128.31, 126.74, 126.42, 124.91, 122.41, 49.73, 30.01,27.44, 27.21, 17.75.HRMS (ESI): m/z calcd for C16H16NaO [M + Na+]: 247.1093; found:247.1094.
2-(8,9,10,11-Tetrahydro-7H-cyclohepta[a]naphthalen-11-yl)acet-aldehyde (6e)Base: K2CO3; yield: 41.0 mg (86%); brown oil.Rf = 0.5 (5% EtOAc in petroleum).1H NMR (400 MHz, CDCl3): = 9.80 (s, 1 H), 8.18 (d, J = 8.7 Hz, 1 H),7.81 (dd, J = 8.1, 1.4 Hz, 1 H), 7.64 (d, J = 8.3 Hz, 1 H), 7.53–7.48 (m, 1H), 7.44–7.40 (m, 1 H), 7.23 (d, J = 8.3 Hz, 1 H), 4.71–4.65 (m, 1 H),3.16–3.02 (m, 2 H), 2.90–2.80 (m, 2 H), 2.06–1.96 (m, 2 H), 1.93–1.84(m, 2 H), 1.82–1.76 (m, 1 H), 1.58–1.49 (m, 1 H).13C NMR (100 MHz, CDCl3): = 202.13, 139.58, 138.13, 132.92,131.88, 130.16, 129.02, 127.27, 126.47, 124.82, 123.03, 46.37, 36.31,32.28, 30.54, 27.57, 25.12.HRMS (ESI): m/z calcd for C17H18NaO [M + Na+]: 261.1250; found:261.1255.
Funding Information
We are grateful to the National Natural Science Foundation of China(Grants 21602161, 21871213, and 21801193), for the startup fundingfrom Wuhan University, and to the China Postdoctoral Science Foun-dation (No. 2018M642894, Z.-S. Liu) for financial support.National Natural Science Foundation of China (21602161)National Natural Science Foundation of China (21801193)National Natural Science Foundation of China (21871213)China Postdoctoral Science Foundation (2018M642894)Wuhan University ()
Acknowledgment
We are very grateful to the Wenbo Liu, Xumu Zhang, Aiwen Lei, andChun-Jiang Wang groups at WHU for instrumentation.
Supporting Information
Supporting information for this article is available online athttps://doi.org/10.1055/s-0039-1690801. Supporting InformationSupporting Information
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© 2020. Thieme. All rights reserved. Synthesis 2020, 52, 834–846