the mixture was stirred for 1 h at 22 °C. A reflux condenser was then added
melting points were observed in all cases studied. They also
show excellent thermal stability (TGA decomposition tem-
perature near 400 °C) with the ionic salts having the smaller
perfluoroalkyl groups in the sulfonimide anions exhibiting
higher thermal stability (Table 1).
The generosity of 3M Co. for the gift of (CF3SO2)2NLi and
the financial support of this research by the National Science
Foundation are gratefully acknowledged.
and the flask was heated at reflux for 12 h. The solution was then shaken
with water (3 3 10 mL) followed by heating at 100 °C at 1.0 3 1022 torr
for 8 h. The resulting clear liquid slowly crystallized on standing at 210 °C
(99%). 2i: dF (CD3CN): 270.79 (t, 3F, 3JHF = 8.25 Hz), 278.88 (s, 6F); dH
(CD3CN): 8.58 (d, 2H, 3JHH = 6.52 Hz), 7.95 (d, 2H, 3JHH = 6.60 Hz), 5.25
3
13C
(q, 2H, JHF 28.17 Hz), 2.68 (s, 3H); d
(CD3CN): 164.88, 146.02,
130.67, 130–118, 59.90.
1 T. Welton, Chem. Rev., 1999, 99, 2071.
2 P. Wasserscheid and W. Keim, Angew. Chem., Int. Ed., 2000, 39,
3772.
3 Ionic Liquids: Industrial Applications for Green Chemistry, R. D.
Rogers and K. R. Seddon, Ed., ACS Symposium Series 818, American
Chemical Society: Washington, DC, 2002.
4 Ionic Liquids as Green Solvents: Progress and Prospects, R. D. Rogers
and K. R. Seddon, Ed., ACS Symposium Series 856, American
Chemical Society: Washington, DC, 2003.
5 S. Wilkes, J. A. Levisky and C. L. Hussey, Inorg. Chem., 1982, 21,
1263.
6 J. S. Wilkes and M. J. Zaworotko, J. Chem. Soc., Chem. Commun.,
1992, 965.
7 F. H. Hurley and T. P. Wier, J. Electrochem. Soc., 1951, 98, 203.
8 H. L. Chun, V. R. Koch, L. L. Miller and R. A. Osteryoung, J. Am.
Chem. Soc., 1975, 97, 3264.
9 D. R. McFarlane, J. Sun, J. Golding, P. Meakin and M. Forsyth,
Electrochim. Acta, 2000, 45, 1271.
Notes and references
† Typical procedure for 1b. Into a 50 mL flask were charged (C4F9SO2)2NH
(8.6 mmol) and excess trimethyl orthoacetate (15 mL). The resulting
solution was refluxed under N2 for 12 h. After removal of excess trimethyl
orthoacetate and other volatile products via vacuum, sublimation of the
solid residue under high vacuum (60 °C/20 mmHg) gave a white solid.
Further recrystallization from acetonitrile gave a colorless flaky solid (5.5
mmol, 64%). Selected data for 1b: dH 3.55 (s); dF –80.1 (m, 3F), 2105.9 (m,
2F), 2120.0 (m, 2F), 2124.9 (m, 2F); d 40.44; MS (m/z) 376 (M+
2
13C
C4F9, 35%), 312 (M+ 2 C4F9SO2, 85%).
‡ Typical procedure for ionic liquid (2d). All reactions were carried out in
a 50 mL flask fitted with a glass–Teflon valve using chloroform as solvent.
A slight excess (1.1 mmol) of 1-ethylimidazole was mixed with 1.0 mmol
of 1b and heated to 70 °C for 5 h. Then solvent and excess ethylimidazole
were removed via vacuum. The remaining colorless liquid was further held
under high vacuum at 120–140 °C for 8 h (2d, 100%). Selected data for 2d:
nKCl 3158, 3124, 2995, 1575, 1473, 1355, 1216, 1077, 1033, 1010, 846, 747,
650, 591 cm21; dH 8.37 (s, 1H), 7.36 (s, 1H), 7.31 (s, 1H), 4.14 (q, 2H, 3JHH
10 D. R. MacFarlane, J. Sun, M. Forsyth, P. Meakin and N. Amini, J. Phys.
Chem., 1999, 103, 4164.
11 S. Singh and D. D. DesMarteau, Inorg. Chem., 1990, 29, 2982.
12 D. D. DesMarteau and V. Montanari, Chem. Commun., 1998, 2241.
13 J. Zhang and D. D. DesMarteau, J. Fluorine Chem., 2001, 111, 253.
14 D. D. DesMarteau and V. Montanari, Chem. Lett., 2000, 1052.
3
= 7.3 Hz), 3.79 (s, 3H), 1.44 (t, 3H, JHH = 7.3 Hz); dF 280.3 (m, 3F),
13
2112.7 (m, 2F), 2120.4 (m, 2F), 2125.2 (m, 2F); d C 135.6, 123.7, 122.0,
44.9, 35.9, 14.5.
§ Typical procedure for 2i. As above, 4-picoline (1.5 mmol) was added to
10 mL of methylene chloride. Then 1c (1.5 mmol) was added under N2 and
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