A clean one-pot synthesis of tetrahydrobenzo[b]pyran derivatives catalyzed by hexadecyltrimethyl ammonium bromide in aqueous media

Abstract: An efficient and convenient approach to the synthesis of 2-amino-3-cyano-4-aryl-7,7-dimethyl-5-oxo-4H-5,6,7,8-tetrahydrobenzo[b]pyran derivatives using hexadecyltrimethyl ammonium bromide (HTMAB) as the catalyst (10 mol%) is described. This method provides several advantages such as neutral conditions, high yields and simple work-up procedure, in addition water was chosen as a green solvent.