Redox-neutral ipso/ortho alkenylcyanation of(hetero)arylboronic acid enabled by 1,4-rhodium migration and fragmentation

A mild,chemoselective,redox-neutral ipso/ortho alkenylcyanation of arylboronic acids with homopropargylic malononitriles via 1,4-rhodium migration and fragmentation is reported.A variety of 2-vinyl arylnitriles are obtained in good yields(51examples,ava.69%yields)through this strategy,which is characterized by its broad substrate scope,great functional group tolerance,and mild conditions.Mechanism studies indicate that the fragmentation is temperature dependent.The primary asymmetric exploration for the non-fragmentation product already shows promising results.The separation of the two cyano groups of homopropargylic malononitriles results in the formation of aromatic nitrile and aliphatic nitrile in one molecule,which enables the further transformations of the products.