An efficient one-pot synthesis of pyrano[3,2-c]quinolin-2,5-dione derivatives catalyzed by l-proline

Abstract

A series of 4-Aryl-6-methyl-3,4-dihydro-2H-pyrano[3,2-c]quinolin-2,5(6H)- diones were synthesized via the three-component reactions of aromatic aldehydes, 4-hydroxy-1- methylquinolin-2(1H)-one, and Meldrum's acid catalyzed by L-proline. The structures of the products were identified by spectroscopic analysis. A mechanism for this three-component reaction catalyzed by L-proline was proposed. © 2012 by the authors.