Efficient Cu-Catalyzed Asymmetric Conjugate Additions of Alkylzincs to Trisubstituted Cyclic Enones
作者:Sylvia J. Degrado、Hirotake Mizutani、Amir H. Hoveyda
DOI:10.1021/ja021081x
日期:2002.11.1
The first examples of efficient catalytic asymmetric conjugate addition (ACA) of alkylzincs to trisubstituted cyclicenones is disclosed. These Cu-catalyzed reactions proceed efficiently with five- and seven-membered ring substrates to afford the desired products in >/=95% ee. Intermediate enolates can be trapped with alkyl halides to generate a quaternary stereogenic center. The requisite chiral ligand
公开了烷基锌与三取代环烯酮的有效催化不对称共轭加成(ACA)的第一个实例。这些铜催化的反应与五元环和七元环底物一起有效地进行,以 >/= 95% ee 提供所需的产物。中间体烯醇可以被烷基卤化物捕获以生成四元立体中心。必需的手性配体由市售材料制备,并且可以原位使用而无需在商业级 (CuOTf)2.PhMe 存在下进一步纯化。