Regioselective and Geometrically Controlled Heck 1,1-Diarylation of Unactivated Aliphatic Alkenes.

Pd-catalyzed double Heck reaction allows regioselective 1,1-diarylation of unactivated aliphatic alkenes. When two different aryl bromides are used, the second aryl rings are added trans to aliphatic chains in the main olefinic isomers, consistent with a mechanism of two consecutive Heck arylations at the terminal carbons.