Multicomponent synthesis of substituted 3-styryl-1H-quinoxalin-2-ones in an aqueous medium

Abstract A multicomponent synthesis of substituted 3-styryl-1 H -quinoxalin-2-ones is described. Sequential reactions of o -phenylenediamine with sodium pyruvate and aldehydes in 20% aqueous acetic acid containing sodium acetate provided the target products in good to high yields. The reaction is proposed to proceed via initial condensation of the diamine and pyruvate partners followed by an aldol condensation-type mechanism.