1221169-10-3Relevant articles and documents
A palladium-catalysed enolate alkylation cascade for the formation of adjacent quaternary and tertiary stereocentres
Streuff, Jan,White, David E.,Virgil, Scott C.,Stoltz, Brian M.
experimental part, p. 192 - 196 (2010/10/20)
The catalytic enantioselective synthesis of densely functionalized organic molecules that contain all-carbon quaternary stereocentres is a challenge to modern chemical methodology. The catalytically controlled, asymmetric α-alkylation of ketones represents another difficult task and is of major interest to our and other research groups. We report here a palladium-catalysed enantioselective process that addresses both problems simultaneously and allows the installation of vicinal all-carbon quaternary and tertiary stereocentres at the α-carbon of a ketone in a single step. This multiple bond-forming process is carried out on readily available β-ketoester starting materials and proceeds by conjugate addition of a palladium enolate, generated in situ, to activated Michael acceptors. As a result, the CO2 moiety of the substrate is displaced by a Cg-C fragment in an asymmetric cut-and-paste reaction with high yield, diastereomeric ratio and enantiomeric excess.
