A Basic Ionic Liquid Catalyzed Reaction of Benzothiazole, Aldehydes, and 5,5-Dimethyl-1,3-cyclohexanedione: Efficient Synthesis of Tetrahydrobenzo[b]pyrans

摘要

A fast, mild, and quantitative procedure for the preparation of tetrahydrobenzo[b]pyran derivatives in the presence of an easily accessible basic ionic liquid-[bmIm]OH(3-butyl-1-methylimidazoliumhydroxide) as the catalyst has been developed. The ionic liquid was stable during the reaction process and could also be reused at least nine times with consistent activity. This procedure may be a practical alternative to the existing procedures to meet the need of academe as well as industries.