Transition metal–catalyzed synthesis of heterocycles using boronic acid-based reagents: Mechanistic insights and recent advances

Heterocyclic compounds represent essential structural motifs in pharmaceuticals, agrochemicals, natural products, and functional materials. Among various synthetic approaches, organoboron compounds, particularly boronic acids and related organoboron reagents, have emerged as versatile building blocks owing to their high chemical stability, low toxicity, and excellent functional-group tolerance. In combination with transition metal catalysts, these reagents enable the efficient construction of diverse heterocyclic frameworks through C–C and C–heteroatom bond-forming transformations. This review summarizes recent advances in transition metal-catalyzed heterocycle synthesis using boronic acid-based reagents, with particular emphasis on catalytic systems, reaction mechanisms, and synthetic applications. Emerging sustainable strategies, including photocatalytic, electrochemical, and heterogeneous catalytic approaches, are also discussed. Finally, the current challenges and future perspectives of boronic acid-enabled transition metal catalysis for heterocyclic synthesis are highlighted.