Organocatalyzed Enantioselective C-N Bond-Forming SNAr Reactions for Synthesizing Stereogenic-at-Boron BODIPYs.

Abstract

The precise construction of boron stereogenic centers represents a significant, yet challenging frontier in asymmetric catalysis, garnering growing attention in recent years. However, feasible catalysis has primarily been limited to transition-metal-catalyzed desymmetrization of pro-chiral BODIPY molecules, while enantioselective synthesis via organocatalysis remains unexplored. Herein, we achieve an organocatalyzed C-N bond-forming SNAr reaction of 3,5-dihalogen BODIPYs via phase-transfer catalysis, enabling the efficient synthesis of a broad range of boron-stereogenic BODIPYs with excellent enantioselectivities (>40 examples, up to 99% ee). The significance and potential of this catalytic approach are further underscored by the versatile applications of enantioenriched 3-amide BODIPYs in asymmetric synthesis, optical activity regulation, bioimaging, and sensing, promoting the development of boron-stereogenic fluorophores.