Photoredox borocarbonylation through 1,2-boron migration

Abstract

Organoboron compounds are fundamental building blocks in organic synthesis, and recent advances in boron-migration reactions have attracted significant attention. However, carbonylative transformations featuring a 1,2-boron shift remain largely unexplored, with limited strategies available for the incorporation of exogenous carbonyl groups. We report an unprecedented 1,2-boron migratory carbonylation enabled by visible-light photoredox catalysis, in which carbon monoxide (CO) serves as an abundant and convenient C1 source to trap translocated alkyl radicals generated after 1,2-boron migration. The methodology provides an efficient and streamlined approach to synthesize structurally complex and diversely functionalized β-boryl thioesters under mild conditions. Notably, this reaction enables a functional-group translocation within a single molecule, allowing for the positional exchange between a carbonyl and a boryl group via sequential CO₂ extrusion, 1,2-boron migration, and CO insertion.