Zn-Mediated Fragmentation of β-Boryl NHPI Esters Enabling the Radical 1,2-Boron Shift for the Synthesis of gem-Difluoroalkenyl Boronates

Boron migration is a type of vital and intriguing reaction in organic synthesis. Herein, a new approach for the synthesis of gem-difluoroalkenyl boronates via the Zn-mediated 1,2-boron radical shift of β-boryl NHPI esters is developed. These β-boryl alkyl radicals subsequently undergo a 1,2-boron shift to produce valuable alkyl radical species, which can be further trapped by α-trifluoromethyl alkenes to construct a diverse array of gem-difluoroalkenyl boronates, including pharmaceutical molecules. Moreover, this type of cross-coupling process can be used for late-stage modification of important molecular scaffolds to build intricately structured organic molecules.