Regio- and Enantioselective Synthesis of Pyrrolidines Bearing a Quaternary Center by Palladium-Catalyzed Asymmetric [3 + 2] Cycloaddition of Trimethylenemethanes
作者:Barry M. Trost、Tom M. Lam、Melissa A. Herbage
DOI:10.1021/ja312351s
日期:2013.2.20
Herein we describe the first use of disubstituted donors in the palladium-catalyzed trimethylenemethane (TMM) cycloaddition resulting in an enantioselective synthesis of highly substituted pyrrolidines. These cyanoalkyl donors 1 form all-carbonquaternary centers in a catalytic, asymmetric, and intermolecular manner uniquely using diamidophosphite ligands L2 and L3, generating synthetically important
Enantioselective Construction of Pyrrolidines by Palladium-Catalyzed Asymmetric [3 + 2] Cycloaddition of Trimethylenemethane with Imines
作者:Barry M. Trost、Steven M. Silverman
DOI:10.1021/ja210981a
日期:2012.3.14
phosphoramidite ligands developed in our laboratories. The conditions developed to effect an asymmetric TMM reaction using 2-trimethylsilylmethyl allyl acetate were shown to be tolerant of a wide variety of imine acceptors to provide the corresponding pyrrolidine cycloadducts with excellent yields and selectivities. Use of a bis-2-naphthyl phosphoramidite allowed the successful cycloaddition of the parent