Palladium-Catalyzed Asymmetric Benzylic Alkylation of Active Methylene Compounds with alpha-Naphthylbenzyl Carbonates and Pivalates

摘要

A Pd/(R)-H-8-BINAP-catalyzed asymmetric benzylic alkylation of active methylene compounds has been developed. The reaction proceeds without the use of an external base, and the starting racemic diarylmethyl carbonates are converted into the optically active coupling products which contain the benzylic chiral stereocenter by a dynamic kinetic asymmetric transformation (DYKAT). Additionally, with suitable carbonates bases, the same palladium catalysis allows the corresponding pivalates to be adopted in the same DYKAT process.