Kinetic study of Michael addition catalyzed by N-methylimidazole in ionic liquids:: Residual N-methylimidazole in ionic liquids as a strong base

Michael addition of malonodinitrile to chalcone was studied in classical organic solvent as well as in some common ionic liquids (ILs). Kinetic studies proved that the reaction proceeded faster in the studied ILs than in molecular solvents. N-methylimidazole was found to be a better basic catalyst in some ILs than in conventional solvents. Residual N-methylimidazole in imidazolium-based ILs can act as a basic catalyst. (C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008.