Recent advances and perspectives on the synthesis and C–H bond functionalization of quinoxalin-2(1H)-one

Over the past few decades, quinoxalin-2(1H)-one derivatives are serving as active components in diverse families of drugs such as antimicrobial, anticancer, antithrombotic agents and protein kinase inhibitor. Previously, significant attention has been marked for its synthesis and recent years have also observed an upsurge in the modification of this scaffold as well as its functionalization. This review (2008–2020) focused on selective C–H bond functionalization namely arylation, amination, acylation, amidation, alkylation, benzylation, alkoxycarbonylation, cyanoalkylation and phosphorylation etc. at C-3 position of quinoxalin-2(1H)-one. Additionally, alternative complimentary route (radical cyclization protocol) for its synthesis part is well elaborated herein. We also briefly summarized the mechanistic pathway of the C–H bond functionalization approach.