A Copper(I)-Catalyzed Radical-Relay Reaction Enabling the Intermolecular 1,2-Alkylborylation of Unactivated Olefins

The first catalytic intermolecular 1,2-alkylborylation reaction via a radical-relay mechanism between unactivated olefins, bis(pinacolato)diboron, and an alkyl electrophile is reported. Successful implementation of this method requires that the competing boryl substitution retarded to facilitate radical relay. This challenge was overcome using electronically or sterically demanding electrophiles, which results in simultaneous highly regioselective introduction gem-difluoro, monofluoro, tertiary, secondary group across C?C double bond.