Palladium/Unichiral Ligand‐Catalyzed Decarboxylative Asymmetric Protonation of Racemic β‐Oxoallyl Esters

International audienceThe palladium‐catalyzed decarboxylative asymmetric protonation (DAP) of racemic allyl β‐keto esters using achiral protic species, first disclosed in 2006, is now a mature methodology for applications in asymmetric organic synthesis. In contrast, the mechanism of protonation remains unclear despite experimental and computational studies. The aim of this review is, firstly, to gather together the literature results, observations and proposals and, secondly, to suggest, for the enantioselectivity‐determining step, transition states depending on the substrate and the proton source