Palladium‐catalyzed decarboxylative alkynylation of α‐acyloxyketones triggered by C(sp3)−O bond cleavage is disclosed. The decarboxylation strategy featuring a neutral reaction condition enabled an unprecedent catalytic alkynylation of a ketone enolate. The reaction was applied to a variety of substrates, giving desired products in good yields. We successfully obtained X‐ray crystallography of a new palladium–enolate intermediate that was synthesized by a reaction of [Pd(cod)(CH2TMS)2] with XPhos and α‐acyloxyketone at room temperature, indicating facile C(sp3)−O bond disconnection.

We herein report palladium(0)-catalyzed decarboxylative cyclization of α-acyloxyketones having an allene moiety in the tether, giving various cyclohexanone derivatives. DFT calculations suggested that the reaction proceeds in the following sequence:...