HETEROGENEOUS CATALYSTS IN THE ALKYLATION OF IMIDAZOLES

Article abstract of DOI:10.1007/BF01169831

The reaction of imidazoles with alcohols at 300-400 deg C was studied in the presence of heterogeneous γ-Al2O3 catalysts and Y zeolites.The major reaction was found to be N-alkylation.This reaction is accompanied by C-alkylation on γ-Al2O3, while the selectivity relative to N-alkylation is close to 100percent on zeolite catalysts.The greatest activity with 100percent selectivity was found for H zeolite.The alkylation of methanol and ethanol by 2-methylimidazole at 310-320 deg C gave 1,2-dimethylimidazole in ca. 100percent yield and 1-ethyl-2-methylimidazole in 90percent yield respectively.The reaction of methanol and imidazole gave 1-methylimidazole in 99percentyield.This catalyst displays high stability and capacity for oxidative regeneration.