Y. Xiao, S.V. Malhotra / Journal of Organometallic Chemistry 690 (2005) 3609–3613
3613
solution. A solution of N-ethyl-pyridinium bromide
0.2 mol) was added to the reaction mixture. As reaction
took place and ILs formed, a yellow precipitate of silver
I) bromide started to be observed. The mixture was stir-
out at high temperature and obtain similar results.
+
À
Combination of [EtPy] [CF COO] -FeCl is found to
3 3
(
be an excellent solvent–catalyst system, which could effi-
ciently substitute the aluminum catalyst system. Appli-
cations of the pyridinium based ILs as solvents for
number of other reactions are under investigation in
our laboratory.
(
red at room temperature for a certain time until no more
precipitate formed. The stirring was stopped and precip-
itates allowed to settle at the bottom of the beaker with
clear water layer at the top. Because N-ethyl pyridinium
bromide is hygroscopic, silver (I) trifluoroacetate is used
in excess. Therefore, we add 1 M solution of N-ethyl
pyridinium bromide drop by drop. This step is repeated
of AgBr are formed. To make sure no excess N-ethyl
pyridinium bromide in the mixture, we test with 1 M sil-
ver (I) trifloroacetate solution. Finally, the mixture is
stirred for 10 min, and the precipitate of silver (I) bro-
mide filtered off. Any color and impurities present in
the synthesized ionic liquids could be removed by pass-
ing ILs through a charcoal column with distilled water
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[
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2
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3
3
.2. Acylation
(
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3
3
1
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(
[
[
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(
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4
h. After the reaction was over, the mixture was diluted
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vigorously. The organic layer was separated from ionic
liquid. Any leftover organic material was extracted with
ethyl ether and the ionic liquid was dried at 65 ꢁC under
vacuum to remove moisture and then reused. The com-
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[
[
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4
. Conclusion
The pyridinium based ILs are suitable media for Fri-
[
[
[
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