Microwave‐Assisted Synthesis of Heterocycles from Aryldiazoacetates

Abstract

Herein, we describe a rapid microwave-assisted, metal-free synthesis of substituted quinoxalinones and quinoxalines using the carbene-mediated reaction between aryldiazo esters and 1,2-diamines. The reaction can encompass a range of substituents and structural variations to afford quinoxalin-2-ones in 14–80 % yield and corresponding quinoxalines in good to excellent yields upon oxidation (67–96 %). The approach can be employed to generate symmetrical and unsymmetrical 2,3-diarylquinoxalines, bis-quinoxalines as well as novel quinoxaline-substituted diazo esters and should be a valuable addition to the heterocycle synthesis toolbox.