Brønsted Acidic Ionic Liquid as an Efficient and Reusable Catalyst for Synthesis of 14-Aryl- or 14-Alkyl-14H-dibenzo[a,j]xanthenes under Solvent-Free Conditions

Abstract

A mild and efficient method has been developed for the preparation of 14-aryl- or 14-alkyl-14H-dibenzo[a,j]xanthenes from one-pot condensation of aldehydes with 2-naphthol using catalytic amount of Brønsted acidic ionic liquid ([TEBSA][HSO4]) under thermal solvent-free conditions. Excellent yields, short reaction times, easy workup and reusability of the catalyst as well as solvent-free conditions are advantages of this procedure.