One-pot synthesis of dihydropyrano[c]chromene derivatives by using BF 3•SiO2 as catalyst

Abstract

Silica-supported boron trifluoride (BF3•SiO2) is an efficient, readily available, and reusable catalyst for the synthesis of 2-amino-5-oxo-4-aryl-4H,5H-pyrano[3,2-c]chromene-3-carbonitrile or carboxylic acid ethyl ester derivatives by condensation of 4-hydroxycoumarin, an aldehyde, and an alkylnitrile. © 2013 by Walter de Gruyter Berlin Boston 2013.