Fluorescence sensing and intracellular imaging of Pd2+ ion by a novel
coumarinyl-rhodamine Schiff base†
Arup Kumar Adak, Saikat Manna, Bankim Chandra Ghosh, Sudipta Pathak, Rakesh Purkait and
Chittaranjan Sinha
O NN
N
ONH2
CHOOHO
Me
O
O NN
N
ON
OHO
Me
O
Ethanol, Reflux
HCR
A
B
CHOOHO
Me
O
O NN
N
ONH2
OHO
Me
OOHHO
O NN
COOH
Cl
A
B
i ii
iii
Scheme S1: Structure and synthesis of sensor HCR where (i). Ethyl acetoacetate, Conc. H2SO4;
(ii). Hexamine, Acetic acid; (iii). Excess Ethelene diamine, EtOH, Reflux.
Electronic Supplementary Material (ESI) for New Journal of Chemistry.This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2019
Figure S1. FTIR spectrum of HCR.
Absorption, cm-1 Assignments
~3400
2970.18
~2800
1727.39
1668.08
1614.36
~1600
1512.24
1218.35
O – H stretching (broad and very weak)
C-H stretching (Ar-H)
C – H stretching (-CH3 and –CH2-)
C=O stretching (α,β-unsaturated δ-lactone.
C=O stretching (α, β-unsaturated-5-membered amide or -lactam).
C = N stretching (Schiff’s base)
C = C stretching (aromatic ring)
C – N stretching.
C – O – C stretching (aromatic ether)
Figure S2. Mass spectrum of HCR.
Figure S3. 1H NMR spectrum of HCR in CDCl3 solution.
Figure S4. 13C NMR spectrum of HCR in CDCl3 solution.
Fig. S5 The linear dynamic response of HCR for Pd2+ and the determination of the limit of detection (LOD) of Pd2+.
Figure S6: Job’s plot of HCR and Pd2+ reaction and associated absorbance change
Y = A + B*X
Y= (0.596 10-5± 0.060) + (1.099 ± 0.185) *
Figure S7. Benesi-Hildebrand plot obtained from the fluorescence titration data
Figure S8. FTIR spectrum of [CR--Pd2+]+ complex in KBr pellete
Figure S9. ESI-MS spectrum of [CR--Pd2+]+
Figure S10. Cellular image after treatment with HCR (5 M)
Table S1 Frontier molecular orbitals contributions of HCR
MO Energy (eV) Rodamine CoumarineLUMO+10 0.76 96 4LUMO+9 0.51 38 62LUMO+8 0.46 83 17LUMO+7 0.25 2 98LUMO+6 0.06 100 0LUMO+5 -0.18 100 0LUMO+4 -0.24 99 1LUMO+3 -0.36 8 92LUMO+2 -0.81 95 5LUMO+1 -1.0 20 80LUMO -2.03 1 99HOMO -4.94 100 0HOMO-1 -5.21 100 0HOMO-2 -5.76 100 0HOMO-3 -6.17 95 5HOMO-4 -6.41 86 14HOMO-5 -6.44 96 4HOMO-6 -6.5 2 98HOMO-7 -6.77 97 3HOMO-8 -6.89 91 9HOMO-9 -6.92 65 65HOMO-10 -7.04 97 3
Table S2 Frontier molecular orbitals contributions of [CR--Pd2+]+
MO Energy (eV) Pd Rodamine CoumarineLUMO+10 -1.66 34 62 4LUMO+9 -1.82 3 3 95LUMO+8 -2.7 0 100 0LUMO+7 -2.79 0 100 0LUMO+6 -3.02 0 100 0LUMO+5 -3.25 0 100 0LUMO+4 -3.36 1 4 95LUMO+3 -3.82 2 91 6LUMO+2 -3.93 3 25 72LUMO+1 -4.32 55 34 10LUMO -5.26 0 100 0HOMO -7.58 7 7 86HOMO-1 -8.07 0 100 0HOMO-2 -8.46 21 56 23HOMO-3 -8.61 20 24 57HOMO-4 -8.81 27 65 7HOMO-5 -8.89 50 46 4HOMO-6 -9.08 31 39 30HOMO-7 -9.22 2 7 92HOMO-8 -9.33 9 33 59HOMO-9 -9.5 4 73 23HOMO-10 -9.71 15 61 24