1740
Novel Chiral Ionic Liquid (CIL) Assisted Selectivity Enhancement
J. Braz. Chem. Soc.
1.97-2.24 (m, 3H, CH2), 2.36-2.52 (m, 1H, CH2), 3.06-
3.40 (m, 3H, NCH2), 3.79 (d, 1H, J 4.5 Hz, NCH2), 4.12
(t, 2H, J 6.6 Hz, NCH2), 4.20-4.32 (m, 1H, CH); 13C NMR
(75 MHz, CDCl3, TMS) d 13.5, 13.7, 19.1, 19.7, 22.9, 27.9,
28.7, 30.4, 56.1, 56.4, 67.3, 67.4, 168.8.
(25 °C ( 3 °C)) for 24 h. The acetone was evaporated,
the residue was extracted with diethyl ether (3 mL, three
times), separated diethyl ether layer was collected, the
residues were dried under vacuum at 40 °C during 5 h for
the next cycle, the collected solvent was evaporated and
the residues purified by chromatography on SiO2-column
(Petroleum ether:EtOAc = 3:1). All reaction products had
the physical constants and NMR spectra in accord with the
published data. The petroleum ether used was of boiling
range 60-80 °C. Evaporation of solvent was performed at
reduced pressure at 25 ( 3) °C.
CIL 2c
1H NMR (300 MHz, CDCl3, TMS) d 0.68-0.84 (m, 6H,
CH3), 1.08-1.36 (m, 12H, CH2), 1.44-1.88 (m, 4H, CH2),
2.02-2.21 (m, 3H, CH2), 2.42-2.62 (m, 1H, CH2), 3.13-3.40
(m, 3H, NCH2), 3.71 (s, 1H, NCH2), 4.10 (t, 2H, J 6.6 Hz,
NCH2), 4.26-4.38 (m, 1H, CH); 13C NMR (75 MHz, CDCl3,
TMS) d 14.0, 14.0, 22.1, 22.5, 22.6, 25.6, 25.9, 26.7, 28.5,
28.6, 31.3, 31.5, 53.7, 53.7, 64.9, 67.0, 168.1.
Supplementary Information
Supplementary data are available free of charge at
CIL 2d
1H NMR (300 MHz, CDCl3, TMS) d 0.72-0.88 (m,
6H, CH3), 1.05-1.38 (m, 20H, CH2), 1.52-1.94 (m, 4H,
CH2), 2.15 (d, 3H, J 3.9 Hz, CH2), 2.47-2.63 (m, 1H, CH2),
3.13-3.50 (m, 3H, NCH2), 3.52-3.74 (m, 1H, NCH2), 4.14
(t, 2H, J 6.9 Hz, NCH2), 4.23-4.38 (m, 1H, CH); 13C NMR
(75 MHz, CDCl3, TMS) d 14.2, 14.2, 22.1, 22.7, 22.7, 25.9,
25.9, 27.0, 28.5, 28.5, 29.3, 29.3, 29.3, 29.3, 31.8, 31.9,
53.9, 53.9, 66.9, 66.9, 168.1.
Acknowledgments
We thank Dr. Zhi-Yong Xue (Wuhan University,Wuhan,
China) for help in the HPLC analysis and the National
Natural Science Foundation of China (Grant Number:
20972120).
References
CIL 2e
1H NMR (300 MHz, CDCl3, TMS) d 0.61-0.74 (m,
6H, CH3), 0.96-1.22 (m, 28H, CH2), 1.40-1.80 (m, 4H,
CH2), 2.03 (d, 3H, J 5.4 Hz, CH2), 2.45 (d, 1H, J 8.1 Hz,
CH2), 3.18-3.39 (m, 3H, NCH2), 3.70 (s, 1H, NCH2), 4.00
(t, 2H, J 6.6 Hz, NCH2), 4.42-4.34 (m, 1H, CH); 13C NMR
(75 MHz, CDCl3, TMS) d 14.3, 14.3, 22.0, 22.8, 22.8,
26.0, 26.0, 27.1, 28.6, 28.6, 29.2, 29.2, 29.4, 29.4, 29.7,
29.7, 29.7, 29.7, 32.0, 32.0, 53.3, 53.3, 67.0, 67.0, 167.9.
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CIL 2f
1H NMR (300 MHz, CDCl3, TMS) d 0.78-0.97(m, 6H,
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