Phosphosulfonic acid, an efficient solid acid catalyst for the one-pot preparation of 14-aryl-14H-dibenzo[a,j]xanthenes and 1,8-dioxooctahydroxanthenes under solvent-free conditions

Abstract

An expeditious procedure for the synthesis of 14-aryl-14H-dibenzo[ a,j]xanthenes and 1,8-dioxooctahydroxanthenes through a one-pot pseudo three component condensation of β-naphthol or dimedone with various aromatic aldehydes is described. This green protocol is catalyzed by phosphosulfonic acid, and proceeds efficiently in the absence of any organic solvent under optimized, mild, green and environmentally benign reaction conditions in high yields within 20-55 min. Copyright ©2013 SCS.