Palladium-Catalyzed Decarboxylative Allylic Alkylation of Allylic Acetates with β-Keto Acids

Article abstract of DOI:10.1021/jo00354a001

In the presence of a catalytic amount of tetrakis(triphenylphosphine)palladium, β-keto acids react with allylic acetates at ambient temperature to produce α-allylic ketones in good yields with quantitative decarboxylation.This palladium-catalyzed decarboxylative allylic alkylation of allylic acetates with β-keto acids is characterized by high regio- and stereoselectivity.Allylation of β-keto acid takes place at the carbon atom bearing a carboxyl group.Allylic alkylation of allylic acetate with β-keto acid occurs at the less substituted end of the allyl group.The resultant carbon-carbon double bond of the α-allylic ketone has the E configuration.Allylic alkylation of lactone 25 with benzoylacetic acid proceeds preferably with retention of configuration, indicative of trans attack of the enolate on the (?-allyl)palladium intermediate from the opposite side of palladium even in the coexistence of free carboxylic acids.