Supporting Information
Catalytic performance of dicationic ionic liquids and ZnBr2 in the reaction of epichlorohydrin and carbon dioxide: Kinetic study
Pooja Jaiswal, Mahesh N. Varma*
Department of Chemical Engineering, Visvesvaraya National Institute of Technology (VNIT), South Ambazari Road, Nagpur (M.H.) 440010, India
Spectral characteristics of synthesized dicationic ionic liquids
In the present study, 1-(3-methylimidazolium), 3-(2, 3-dimethylimidazolium) propane dibromide [C3 (mim) (dmim) Br2], 1-(3-methylimidazolium), 3-(pyridine) propane dibromide [C3 (mim) (pyr) Br2], 1, 3-bis(3-methylimidazolium-1-yl)propane dibromide [C3 (mim) (mim) Br2], 1, 3-bis(3-methylimidazolium-1-yl)butane dibromide [C4 (mim) (mim) Br2], 1, 3-bis(3-methylimidazolium-1-yl)hexane dibromide [C6 (mim) (mim) Br2] were synthesized. The structures of the synthesized DILs were confirmed by 1H and 13C NMR. Spectral characteristics of synthesized DILs are as follows
1-(3-methylimidazolium), 3-(pyridine) propane dibromide (Fig. S1)
1H- NMR (400 MHz, DMSO-d6, δ, ppm): 2.76 (6, 2H, qt, J =6.9Hz), 3.99 (1,3H, s), 4.55 (5, 2H,t J = 6.8 Hz), 4.99 (7, 2H, t, J =7.32 Hz), 7.85 (3, 1H, s), 8.01 (4, 1H, s), 8.27 (9, 11, 2H, t, J = 6.8Hz), 8.75 (10, 1H, t, J = 7.8Hz), 9.47 (8,12, 2H, d, J = 5.8HZ), 9.55 (2, 1H, s)
13C- NMR (100MHz, DMSO-d6, δ, ppm): 31.01 (C6), 36.07 (C1), 45.7 (C7), 57.37 (C5), 122.16 (C3), 123.60 (C4), 128.18 (C2), 136.7(C10, C12), 144.82 (C9), 145.79 (C8, C11)
Fig. S1 Structure of 1-(3-methylimidazolium), 3-(pyridine) propane dibromide [C3 (mim) (pyr) Br2]
1-(3-methylimidazolium), 3-(2, 3-dimethylimidazolium) propane dibromide (Fig. S2):
1H- NMR (400 MHz, DMSO-d6, δ, ppm): 2.04 (6, 2H, m), 2.7 (8, 3H, s), 3.79 (1, 3H, s), 3.82 (10,3H, s), 4.58 (5, 7,4H, m), 7.76 (3, 4, 4H, m), 9.4 (2,2H, s)
13C- NMR (100MHz, DMSO-d6, δ, ppm): 30.0 (C6), 34.90(C8), 36.5 (C1, C10), 46.3 (C5, C7), 122.8 (C3, C4, C11, C12), 124.3 (C2), 137.3 (C9)
Fig. S2 Structure of 1-(3-methylimidazolium), 3-(2, 3-dimethylimidazolium) propane dibromide [C3 (mim) (dmim) Br2]
1, 3-bis(3-methylimidazolium-1-yl)propane dibromide (Fig. S3):
1H- NMR (400 MHz, DMSO-d6, δ, ppm): 2.58 (6, 2H, m), 3.82 (1, 9, 6H, s), 4.47 (5, 7, 4H, t, J = 6.88Hz), 7.9 (4, 11, 2H, m), 8.02 (3, 10, 2H, m), 9.6 (2, 8, 2H, s)
13C- NMR (100MHz, DMSO-d6, δ, ppm): 29.9 (C6), 36.1 (C1, C9), 45.7 (C5, C7), 122.3 (C3, C10), 123.6 (C4, C11), 136.7 (C2, C8)
Fig. S3 Structure of 1, 3-bis(3-methylimidazolium-1-yl)propane dibromide [C3 (mim) (mim) Br2]
1, 3-bis(3-methylimidazolium-1-yl)butane dibromide (Fig. S4):
1H- NMR (400 MHz, DMSO-d6, δ, ppm): 1.93 (6, 7, 4H, m), 3.97 (1, 10, 6H, s), 4.37 (5, 8, 4H, t, J = 2Hz), 7.78 (4, 12, 2H. t, J = 3.16Hz), 7.90 (3, 11, 2H, t, 3.24), 9.4 (2, 9, 2H, s).
13C- NMR (100MHz, DMSO-d6, δ, ppm): 25.99 (C6, C7), 35.96 (C5, C8), 47.98 (C1, C10), 122.15 (C4, C12), 123.42 (C3, C11), 136.12 (C2, C9)
Fig. S4 Structure of 1, 3-bis(3-methylimidazolium-1-yl)butane dibromide [C4 (mim) (mim) Br2]
1, 3-bis(3-methylimidazolium-1-yl)hexane dibromide (Fig. S5):
1H- NMR (400 MHz, DMSO-d6, δ, ppm): 1.28 (7, 8, 4H, m), 1.81 (6, 9, 4H, m), 3.87( 1,12, 6H,s), 4.21 ( 5, 10, 4H, t, J = 2 Hz), 7.75 (4,14, 2H, t, J = 0.5Hz), 7.85 (3, 13, 2H,t,J = 0.5Hz), 9.30 (2,11, 2H,s)
13C- NMR (100MHz, DMSO-d6, δ, ppm): 24.72 (C7, C8), 29.05 (C6, C9), 35.77 (C5, C10), 48.54 (C1, C12), 122.2 (C4, C14), 123.5 (C3, C13), 136.45 (C2, C11)
Fig. S5 Structure of 1, 3-bis(3-methylimidazolium-1-yl)hexane dibromide [C6 (mim) (mim) Br2]
Spectral characteristics of 4-chloromethyl-1,3-dioxolan-2-one
Structure of the product i.e., 4-chloromethyl-1,3-dioxolan-2-one (Fig. S6 ) was confirmed by 1H NMR and 13C NMR. Spectral characteristics of 4-chloromethyl-1,3-dioxolan-2-one are as follows
1H NMR (400.13 MHz, CDCl3, δ, ppm): 3.63 (1, 2H, dd, J = 6.82 Hz), 4.36 (3, 1H, m), 4.60 (2, 1H, dd, J =7 Hz), 5.04 (2, 1H, dd, J = 5.4 Hz), 13C NMR (100.4MHz, CDCl3, δ, ppm): 45.81 [C1], 67.06 [C2], 74.60 [C3], 154.69 [C4] (Fig. 6).
Fig. S6 Structure of 4-chloromethyl-1,3-dioxolan-2-one.
Table S1
Comparison of activation energy (Ea) and rate constants (kobs) for various catalytic systems at different temperatures
Catalyst / Cocatalyst / Temperature( 0C ) / kobs* 10-2
(min-1) / Ea
(kJ mol-1)
C3 (mim) (pyr) Br2 / ZnBr2 / 90
70
50 / 2.6
1.8
0.7 / 32
C3 (mim) (dmim) Br2 / ZnBr2 / 90
70
50 / 3.5
2.9
1.0 / 30
C3 (mim) (mim) Br2 / ZnBr2 / 90
70
50 / 5.9
4.2
2.1 / 25
C4 (mim) (mim) Br2 / ZnBr2 / 90
70
50 / 7.2
5.3
2.8 / 23
C6 (mim) (mim) Br2 / ZnBr2 / 90
70
50 / 9.6
7.6
4.1 / 20