Regio- and Stereospecific 1,3-Allyl Group Transfer Triggered by a Copper-Catalyzed Borylation/ortho-Cyanation Cascade.

A copper-catalyzed borylation/ortho-cyanation/allyl group transfer cascade was developed. Initiated by an unconventional copper-catalyzed electrophilic dearomatization, this process features regio- and stereospecific 1,3-transposition of the allyl fragment enabled by an aromatization-driven Cope rearrangement. This method provides an effective means for the construction of adjacent tertiary and quaternary stereocenters with excellent diastereocontrol.