Optically Pure 1,2-Bis[(o-alkylphenyl)phenylphosphino]ethanes and Their Use in Rhodium-Catalyzed Asymmetric Hydrogenations ofα-(Acylamino)acrylic Derivatives
作者:Yoshiyuki Wada、Tsuneo Imamoto、Hideyuki Tsuruta、Kentaro Yamaguchi、Ilya D. Gridnev
DOI:10.1002/adsc.200404043
日期:2004.6
considerably high enantioselectivity (up to 90%). The single crystal X-ray analysis of the rhodium complex 5c of (S,S)-1,2-bis[phenyl(5′,6′,7′,8′-tetrahydronaphthyl)phosphino]ethane (1c) revealed its δ-type structure with face orientation of the two tetrahydronaphthyl groups and edge orientation of the two phenyl groups. This conformation corresponds to that of the rhodium complex of 1,2-bis[(o-methoxyp
光学纯的(S,S)-1,2-双[(邻烷基苯基)苯基膦基]乙烷1a-d由苯基二氯膦经膦-硼烷作为中间体分四个步骤制备。这些二膦的铑配合物5a-d用于α-(酰基氨基)丙烯酸衍生物(包括β-二取代衍生物)的不对称氢化。观察到β-单取代衍生物的还原具有很高的对映选择性(78-> 99%)。β-二取代衍生物的对映选择性也大大降低(高达90%)。(S,S的铑配合物5c的单晶X射线分析)-1,2-双[苯基(5',6',7',8'-四氢萘基)膦基]乙烷(1c)揭示了其δ型结构,两个四氢萘基的表面取向且两个边沿的取向苯基。该构象对应于1,2-双[(邻甲氧基苯基)苯基膦基]乙烷(DIPAMP)的铑配合物。(的铑配合物R,R)-DIPAMP,其在手性磷是相反的图5c,显示出λ型结构与两个的脸的朝向Ò-甲氧基苯基和两个苯基的边缘取向。这些铑配合物的构象相似性以及不对称氢化中的立体化学结果意味着DIPAMP的甲氧基