Phosphine-directed stereo- & regioselective Ni-catalyzed reactions of Grignard reagents with allylic ethers
作者:Mary T. Didiuk、James P. Morken、Amir H. Hoveyda
DOI:10.1016/s0040-4020(97)10212-5
日期:1998.2
Studies on the directed regio- and stereoselective Ni-catalyzed allylic substitution reactions involving methyl- and phenylmagnesium bromides and various acyclic and cyclic allylic ethers are reported. In the presence of a properly positioned internal Lewis base, CC bonds can be formed catalytically and with excellent levels of selectivity. Internal chelation allows Ni-catalyzed CC bond forming reactions
报道了对直接的区域选择性和立体选择性镍催化的烯丙基取代反应的研究,该反应涉及甲基和苯基溴化镁以及各种无环和环状烯丙基醚。在适当定位的内部路易斯碱的存在下,可以催化形成C canC键,并具有极好的选择性。内部螯合使Ni催化的CC键形成反应易于进行,以高收率,在环境温度和高度区域和立体控制下完成,否则这些反应是非选择性的,缓慢的或根本不发生的。定向烯烃的异构化突出了金属催化烷基化策略的一个特别吸引人的特征:因为初始产物包含一个保留在内部路易斯碱可及范围内的酯基生成位点,