Enantioposition-selective alkynylation of biaryl ditriflates by palladium-catalyzed asymmetric cross-coupling
作者:Takashi Kamikawa、Yasuhiro Uozumi、Tamio Hayashi
DOI:10.1016/0040-4039(96)00517-5
日期:1996.4
Asymmetric cross-coupling of prochiral biaryl ditriflate, 1-[2,6-bis[[(trifluoromethyl)sulfonyl]oxy]phenyl]naphthalene (1) or 1,3-bis[[(trifluoromethyl)sulfonyl]oxy]-2-(biphenyl-2-yl)benzene (4) with triphenylsilylethynylmagnesium bromide in the presence of lithium bromide and 5 mol % of palladium catalyst, PdCl2[(S)-Alaphos], proceeded with high enantioposition selectivity to give high yields of the
前手性联芳基二三氟甲磺酸酯,1- [2,6-双[[((三氟甲基)磺酰基]氧基]苯基]萘(1)或1,3-双[[(三氟甲基)磺酰基]氧基] -2-的不对称交叉偶联在存在溴化锂和5 mol%钯催化剂PdCl 2 [(S)-Alaphos]的情况下,将(biphenyl-2-yl)苯(4)与三苯基甲硅烷基乙炔基溴化镁进行对映体选择性高,从而获得高收率的相应产物。高对映体纯度(高达> 99%ee)的轴向手性单炔基化b联芳基2a或2d。