Palladium Precatalysts for Decarbonylative Dehydration of Fatty Acids to Linear Alpha Olefins

Transition-metal-catalyzed decarbonylative dehydration of even-numbered fatty acids to give valuable odd-numbered alpha olefins has so far been performed using approaches in which the catalyst is formed in situ. We show that well-defined Pd(bis-phosphine) precatalysts eliminate the need for excess phosphine and selectively produce linear alpha olefins under mild conditions and with substantially increased turnover frequency (TOF) and substrate scope. In particular, the new precatalyst Pd(cinnamyl)Cl(DPEPhos) (5) selectively converts substrates containing unprotected aliphatic-alcohol and amine functional groups to their corresponding linear alpha olefins.