Copper(ii)-catalyzed C3-acylation of quinoxalin-2(1H)-ones with methyl ketones via the formal decarbonylation of 1,2-diketones

Abstract

The inexpensive copper(ii) bromide-catalyzed cross-dehydrogenative coupling/Kornblum oxidation/formal decarbonylation of N-substituted/unsubstituted quinoxalinones in DMSO is reported. It has offered a new technique for the cleavage of C(CO)–C(CO) bonds under base- and ligand-free conditions, allowing for the direct synthesis of a diverse range of C3-acylated quinoxalinones. This persulfate-peroxide-free catalytic method provides good yields, a broad substrate scope, and good tolerance to various functionalities. This journal is © The Royal Society of Chemistry, 2026.