Abstract

A novel method was successfully demonstrated towards the synthesis of pyrido[1,2-a]pyrimidines having chloroethyl as an intractable side chain, through dihydrofuranone intermediates. The dihydrofuranone intermediates were synthesized by condensation of 2-aminopyridines with α-acetyl-γ-butyrolactone, which upon cyclization using phosphorus oxychloride or ethanol in sodium ethoxide furnished the pyrido[1,2-a]pyrimidines in good yield.