Enantioselective Construction of All-Carbon Quaternary Centers by Branch-Selective Pd-Catalyzed Allyl–Allyl Cross-Coupling
作者:Ping Zhang、Hai Le、Robert E. Kyne、James P. Morken
DOI:10.1021/ja2039248
日期:2011.6.29
The Pd-catalyzed cross-coupling of racemic tertiary allylic carbonates and allylboronates is described. This reaction generates all-carbon quaternary centers in a highly regioselective and enantioselective fashion. The outcome of these reactions is consistent with a process that proceeds by way of 3,3'-reductive elimination of bis(η(1)-allyl)palladium intermediates. Strategies for distinguishing the
描述了外消旋叔烯丙基碳酸酯和烯丙基硼酸酯的 Pd 催化交叉偶联。该反应以高度区域选择性和对映选择性方式生成全碳四元中心。这些反应的结果与通过双 (η(1)-烯丙基) 钯中间体的 3,3'-还原消除方式进行的过程一致。还描述了区分产物烯烃的策略和在 (+)-α-cuparenone 合成中的应用。