Enantioselective Synthesis of Boron-Stereogenic Compounds with Multiple Chiral Elements via Cobalt-Catalyzed Desymmetric Annulation

Catalytic asymmetric synthesis of boron-stereogenic compounds has garnered growing interest in recent years. However, strategies for constructing boron-stereogenic centers with structural diversity remain underdeveloped, especially compared with the well-established methods for carbon stereocenters formation. Herein, we report an earth-abundant cobalt-catalyzed enantioselective C-H activation/desymmetric annulation of arylamides with prochiral boron-diyne compounds, providing direct access to a wide range of boron-stereogenic heterocycles. Enabled by a cobalt(II)/chiral salicyloxazoline (Salox) catalytic system, this approach effectively addresses the challenge of precise differentiation between two enantiotopic alkyne units. The transformation concurrently establishes a stable boron-stereogenic center together with multiple chiral axes (N-N or C-N) in a single step, featuring a broad substrate scope, good functional group tolerance, and high efficiency. Gram-scale synthesis, directing-group removal, and versatile derivatizations further highlighted the synthetic utility of this strategy. Detailed experimental and computational studies provide in-depth insight into the catalytic mechanism. Notably, the obtained optically pure compounds exhibit promising photoluminescence and circularly polarized luminescence (CPL) properties, underscoring their potential for advanced optical applications.