Evidence for a Non-Concerted, Dissoziative Mechanism of the Palladium-Catalyzed "Enolate Claisen Rearrangement" of Allylic Esters

Dissociation into carboxylic‐acid dianions and palladium complexes rather than a concerted [3,3]‐sigmatropic rearrangement occurs upon exposure of the lithiumenolate derived from allyl phenylacetate tocatalytic Pd0. Only after the fragments escaped from the solvent cage, they combine under carbon‐carbon‐bond formation and give the allylated carboxylic acid