Palladium-catalyzed alkyne insertion/reduction route to trisubstituted olefins.

A new route to trisubstituted olefins through a palladium-catalyzed alkyne insertion/reduction reaction with unactivated alkyl iodides is reported. The reaction proceeds under mild conditions and tolerates a range of functional groups and substitution patterns. Preliminary mechanistic inquiry suggests that the transformation may proceed through a hybrid radical/organometallic pathway.