Eco-Friendly Borylation of Allylic Acetates via Nickel-Catalyzed Dual-Role Base Activation

Abstract

Allylic boronates are valuable synthons in organic chemistry, making the development of efficient and sustainable preparation methods highly desirable. We report a nickel-catalyzed borylation of unactivated allylic acetates using a recyclable N-donor ligand system in ethyl acetate. The method employs an innovative dual-role base that simultaneously activates diboron reagents and reduces air-stable NiBr2, eliminating need for external reductants. The approach shows excellent compatibility across a diverse array of substrates, delivering the desired products with isolated yields up to 97%. Its operational simplicity is evidenced by glovebox-free conditions and successful multi-gram scale implementation (13 mmol scale, yields up to 95%), underscoring the method's practicality as a eco-friendly alternative to conventional allylic borylation.