Catalyst-free one-pot synthesis of Novel 4H,5H-pyrano[2,3-d]pyrido[1,2-a]pyrimidin-5-one derivatives

Abstract

An efficient one-pot synthesis of novel 4H,5H-pyrano[2,3-d]pyrido [1,2-a]pyrimidin-5-one derivatives has been developed. This method involves the three-component condensation of 2‑hydroxy-4H-pyrido[1,2-a]pyrimidin-4-one, aromatic aldehydes and (E)-N-methyl-1-(methylthio)-2-nitroethenamine at 120 °C under neat reaction conditions in Monowave 50 reactor. A simple procedure, catalyst free, short reaction time, high yields and non‐column chromatographic separation are attractive features of this process.