Benzimidazolium ILs for Organic Synthesis

Simple and expeditious procedure has been adopted for the synthesis of a series of novel Carboxyl, Ester and Amide functionalized benzimidazolium based Ionic liquids. The spectroscopic evidences of these ionic liquids have been proved by FT-IR, MASS, NMR. Catalytic activities of CFBILs were evaluated towards the solvent free, one-pot synthesis of 1-amidoalkyl naphthol derivatives. The catalyst has shown excellent stability over wide range of temperature and good recyclability for several runs. While Amide functionalized dicationic benzimidazolium based ionic liquids appraised towards perceptive esterification of carboxylic acids with alkyl/allyl/aryl halides in presence of triethylamine and a thermally stable amide functionalized benzimidazolium perchlorate ionic liquid catalyst was tested its efficacy towards solvent free transamidation of amides and amines. The catalyst has exhibited very good thermal stability and reproducibility. The catalytic activities were found to increase with the acidity of the CFBILs and Amide functionalized ILs which reveal the formation of hydrogen bonding with substrate molecules and this could play a crucial role to facilitate the product formation.