Synthesis of Quinoxalin-2(1H)-ones and Hexahydroquinoxalin-2(1H)-ones via Oxidative Amidation–Heterocycloannulation

Abstract

A metal-catalyst-free synthesis of substituted quinoxalin-2-ones from 2,2-dibromo-1-arylethanone by employing an oxidative amidation–heterocycloannulation protocol is reported. The substrate scope of the reaction has been demonstrated and a possible mechanism for this reaction has also been proposed.

Sulfur-Promoted Access to 3-Arylquinoxalin-2-ones by Oxidative Coupling of o-Phenylenediamines with Arylacetates

“…Consequently, significant synthetic efforts have been devoted to the synthesis of quinoxaline-2-one heterocycles. Traditional synthesis of quinoxalin-2-ones 3 was based on condensation of o -phenylenediamines 1 with arylglyoxalic acids, as well as their esters/amides, and others derivatives 4 . Good results could be obtained as long as the arylglyoxalic derivatives 4 were available.…”