Transition-metal-free solid phase synthesis of 1,2-disubstituted 4-quinolones via the regiospecific synthesis of enaminones

Abstract

Herein, the transition-metal-free economical solid phase synthesis of 1,2-disubstituted 4-quinolones has been developed via the novel regiospecific synthesis of enaminones. Notably, a wide range of enaminones were synthesized via a silica-supported solid-phase reaction in good to excellent yields. The transformation of enaminones to 1,2-disubstituted 4-quinolones and N-methyl-2-aryl-4-quinolone alkaloid was achieved in high yield via an alumina-supported solid phase reaction. In addition, all the synthesized compounds were isolated directly in their pure form from the reaction mixture using an easy workup procedure.