Palladium-catalyzed α,β-dehydrogenation of acyclic ester equivalents promoted by a novel electron deficient phosphinooxazoline ligand.

A unique example of Pd-catalyzed decarboxylative dehydrogenation of fully substituted -acyl allyl enol carbonates is enabled by a new electron deficient phosphinooxazoline (PHOX) ligand. The reaction proceeds from the -enol carbonate to provide dehydrogenation products exclusively in high selectivity, while the -enol carbonate provides the α-allylation product with only minor dehydrogenation. The reaction proceeds with a broad scope of ()-enol carbonates derived from -acyl indoles to furnish acyclic formal α,β-unsaturated ester equivalents.