Electrochemical Functionalization of Pyridines

Abstract

Pyridines are important nitrogen-containing heteroaromatics with wide applications in pharmaceuticals, agrochemicals, ligands, and materials science. However, their selective C–H functionalization remains challenging due to low nucleophilicity, regioselectivity issues, and catalyst deactivation via nitrogen coordination. Traditional methods such as electrophilic substitution, directed metalation, transition-metal catalysis, and N-oxide transformations have enabled significant advances in this field, but often require harsh conditions or pre-functionalized substrates. In contrast, electrochemical synthesis has emerged as a sustainable and versatile alternative, employing electricity as a clean redox agent to enable direct C–H, C–C, and C–heteroatom bond formation under mild, tunable conditions. This review provides a focused overview of how electro-organic synthesis has addressed key challenges in pyridine functionalization associated with traditional methods, tracing its historical development and highlighting recent advances, with particular emphasis on anodic oxidation, cathodic reduction, paired electrolysis, and mediator or metal-catalyzed strategies, thereby offering readers an in-depth understanding of the advancements in this field and its significance in organic synthesis. Key mechanistic insights and representative applications are highlighted to demonstrate the growing potential of electrochemical strategies for scalable, late-stage pyridine diversification. We hope that this review will highlight the salient features of electrochemical strategies for pyridine functionalization in synthetic applications and stimulate the development of new, more advanced methodologies.