Development of an Asymmetric Trimethylenemethane Cycloaddition Reaction: Application in the Enantioselective Synthesis of Highly Substituted Carbocycles
作者:Barry M. Trost、Steven M. Silverman、James P. Stambuli
DOI:10.1021/ja207550t
日期:2011.12.7
azetidine structures, is discussed. The conditions developed to effect an asymmetric TMM reaction using 2-trimethylsilylmethyl allyl acetate were shown to be tolerant of a wide variety of alkene acceptors, providing the desired methylenecyclopentanes with high levels of enantioselectivity. The donor scope was also explored, and substituted systems were tolerated, including one bearing a nitrile moiety. These
Palladium-Catalyzed Asymmetric [3+2] Cycloaddition of Trimethylenemethane with Imines
作者:Barry M. Trost、Steven M. Silverman、James P. Stambuli
DOI:10.1021/ja0753389
日期:2007.10.1
The transition metal-catalyzed trimethylenemethane [3+2] cycloaddition provides a direct route to functionalized heterocycles. Herein, we describe a catalytic, asymmetric protocol for the reaction between 3-acetoxy-2-trimethylsilylmethyl-1-propene and various imines. The corresponding pyrrolidines were obtained in excellent yields and enantioselectivities making use of the novel phosphoramidite L10
Asymmetric Synthesis of Methylenetetrahydrofurans by Palladium-Catalyzed [3 + 2] Cycloaddition of Trimethylenemethane with Aldehydes – A Novel Ligand Design
作者:Barry M. Trost、Dustin A. Bringley、Steven M. Silverman
DOI:10.1021/ja201181g
日期:2011.5.25
The palladium-catalyzed [3 + 2] cycloaddition of trimethylenemethane (TMM) with aldehydes is a direct and efficient route to methylenetetrahydrofurans. Herein we describe the first asymmetric synthesis of methylenetetrahydrofurans utilizing a palladium-TMM complex in the presence of a novel phosphoramidite ligand possessing a stereogenic phosphorus. The method allows for the formation of chiral disubstituted