Enantioselective Intramolecular Reductive Heck Reaction with a Palladium/Monodentate Phosphoramidite Catalyst

A palladium-catalyzed enantioselective reductive Heck reaction of enones using monodentate phosphoramidite ligands is described. ,,','-tetraaryl-1,3-dioxolane-4,5-dimethanol (TADDOL)-based phosphoramidites with palladium(II) acetate, and N-methyl dicyclohexylamine as reducing agent gives the reductive Heck product in high yields and enantioselectivities of up to 90%. The solvent plays an important role and in diethyl carbonate, the chemo- and enantioselectivity appeared to be the highest.