Anchoring 1-methyl-3-(triethoxysilylpropyl)imidazoliumchlorideontosilica-
coated magneticFe3O4 particles affordedthecorrespondingsupportedionicliquid.
Exchanging theCl anion bytreatingwithH2SO4 gave Brønstedionicliquid1-methyl-
3-(triethoxysilylpropyl) imidazoliumhydrogensulfate.Thesynthesizedcatalystwas
characterized byvarioustechniquessuchasinfrared,x-raydiffraction,scanningelectron
microscopy, thermogravimetricanalysis,andelementalanalyses.Theresultsindicated
that thepreparedcatalysthadananostructure.Thecatalyticactivityofthesupported
ionic liquidwasexaminedinthesynthesisofthepolysubstitutedpyridinesbyreactionof
aromatic aldehydeswithacetophenonesandammoniumacetateinmoderatetogood
yields undersolvent-freeconditions.Thecatalystcanbeeasilyrecoveredbyapplyingan
external magneticfieldandreusedforatleastsevenrunswithoutdeteriorationin
catalytic activity.