stable in solution. Excess 2dLi reacted with (1S)-camphanoyl chloride preferentially to form the (SP,Rax,1S) isomer, which was separated by crystallization as enantiopure 3dE, characterized by single-crystal XRD. Preliminary screening tests of this ligand in Rh-catalyzed asymmetric hydrogenations of N-(1-phenylvinyl)acetamide allowed high conversion and up to 59 % ee. Hydrosilylation of acetophenone proceeded
(1S)-
樟脑酸2-异丙基
苯基膦酰基-苯基酯1的非对映异构体分离举例说明了(1S)-
樟脑酰
氯对羟基官能团的不对称膦的对映异构体分离的潜力。由各自的2-OH或2-OSiMe 3前体2a OH和2b - f Si生成的2'-膦酰基
联苯-2-
锂锂的酯化反应,将2-(1 S)-
樟脑酰氧基-
联苯膦3a - c表示为1 :1具有低能垒的非对映异构体混合物,可通过围绕C–C轴旋转来进行相互转换(ΔG #= 70-73千焦耳摩尔-1为图3a和3c中通过31 P VT NMR光谱法)。P不对称化合物3d – f形成1:1的立体异构体混合物。如3d D和3f D的晶体结构分析所示,存在两种优选的非对映异构体共结晶的趋势,并且在溶液中,存在部分异构化为空间较弱的阻转异构体的趋势。[RhCl(cod)(3d D)]络合物4d D在溶液中似乎稳定。2d Li过剩与(1 S)-
樟脑酰
氯优先形成(S P,R ax,1 S)异构体,通过结晶分离为对映体3d