Catalytic stereoselective synthesis of all-carbon tetra-substituted alkenes via Z-selective alkyne difunctionalization†

We report a Ni-catalyzed cascade reaction leading to the arylation of an alkyne-induced acyl migration and the formation of all-carbon tetra-substituted alkenes in good yields with exclusive Z-selectivity. This transformation involves the generation of a nucleophilic vinyl-Ni species through regioselective syn-aryl nickelation of the alkynes, followed by an intramolecular acyl migration. The steric and electronic properties of the phosphine ligands are crucial for achieving high regio- and stereocontrol in this migratory carbo-acylation process. The synthetic utility of the resulting Z-tetra-substituted alkenes is also demonstrated.