Efficient and highly selective production of 10,11-dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-diones using a mesoporous silica-based nanocatalyst

摘要

An efficient and highly selective protocol for the production of 10,11-dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-dione derivatives has been developed. The one-pot multi-component condensation of arylaldehydes with 4-hydroxycoumarin and dimedone in the presence of a mesoporous acidic nanocatalyst, namely nano-N,N,N ',N '-tetramethyl-N-(silica-n-propyl)-N '-sulfo-ethane-1,2-diaminium chloride (nano-[TSPSED][Cl](2)) selectively afforded the mentioned compounds in high yields and in relatively short reaction times. The nanocatalyst was reusable for four times without significant loss of activity. Our catalyst was better than the reported catalysts in terms of three or more of these factors: the reaction temperatures, times, yields, turnover number and turnover frequency. Graphic abstract