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1611802 
Journal Article 
An Alternative to Nitromethane as Solvent: The Promoting Influence of Nitro-Functionalized Imidazolium Salts for Synthesis and Catalysis 
Ren, Y; Li, M; Yang, Jie; Peng, J; Gu, Y 
2011 
1 
Advanced Synthesis & Catalysis
ISSN: 1615-4150
EISSN: 1615-4169 
353 
18 
3473-3484 
WOS:000298332200032 
Nitromethane, a volatile and toxic organic compound, is
commonly used as solvent for organic and catalytic reactions. In order to find an alternative for
this specific nitro-containing organic solvent, the performance of some nitro-functionalized
imidazolium salts such as 1-methyl-3-(4-nitrobenzyl)imidazolium hexafluorophosphate, 1-methyl-3-
(4-nitrobenzyl)imidazolium tetrafluoroborate, 1-methyl-3-(4-nitrobenzyl)imidazolium bis
(trifluoromethanesulfonyl)amide and 1,2-dimethyl-3-(4- nitrobenzyl)imidazolium
hexafluorophosphate, was examined in some reactions including trimethylsilylation of alcohols
with hexamethyldisilazane, ring-opening reactions of 2-aryl-3,4-dihydropyrans with thiophenols or
thiols, and a copper- mediated oxidative coupling of alkynes. As expected, these imidazolium
salts can indeed replace nitromethane in these reactions. Particularly, the imidazolium salt
along with the metal catalyst, if involved, can be easily recovered and reused without
significant loss of activity. The use of these nitro-functionalized imidazolium salts as
alternative solvents for nitromethane not only confers a green aspect to the reaction system, but
also facilitates a rational design of a catalytic system with the concept of green chemistry. 
nitro-functionalized imidazolium salts; oxidative coupling of alkynes; ring-opening of dihydropyran with nucleophiles; trimethylsilylation of alcohols with hexamethyldisilazane