Qiu Liqin, Wu Jing, Chan Shusun, Au-Yeung Terry T-L, Ji Jian-Xin, Guo Rongwei, Pai Cheng-Chao, Zhou Zhongyuan, Li Xingshu, Fan Qing-Hua, Chan Albert S C
Open Laboratory of Chirotechnology of the Institute of Molecular Technology for Drug Discovery and Synthesis and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
Proc Natl Acad Sci U S A. 2004 Apr 20;101(16):5815-20. doi: 10.1073/pnas.0307774101. Epub 2004 Apr 5.
Essentially complete atropdiastereoselectivity was realized in the preparation of biaryl diphosphine dioxide by asymmetric intramolecular Ullmann coupling and oxidative coupling with central-to-axial chirality transfer. A bridged C(2)-symmetric biphenyl phosphine ligand possessing additional chiral centers on the linking unit of the biphenyl groups was synthesized. No resolution step was required for the preparation of the enantiomerically pure chiral ligand. These findings offer a general and practical tool for the development of previously uninvestigated atropdiastereomeric biaryl phosphine ligands. The diphosphine ligand was found to be highly effective in the asymmetric hydrogenation of alpha- and beta-ketoesters, 2-(6'-methoxy-2'-naphthyl)propenoic acid, beta-(acylamino)acrylates, and enol acetates.
通过不对称分子内乌尔曼偶联和具有中心到轴向手性转移的氧化偶联反应制备联芳基二膦二氧化物时，实现了基本完全的阻转非对映选择性。合成了一种在联苯基团连接单元上具有额外手性中心的桥连C(2)对称联苯膦配体。制备对映体纯的手性配体无需拆分步骤。这些发现为开发此前未研究过的阻转非对映异构联芳基膦配体提供了一种通用且实用的工具。发现该二膦配体在α-和β-酮酯、2-(6'-甲氧基-2'-萘基)丙烯酸、β-(酰基氨基)丙烯酸酯和烯醇乙酸酯的不对称氢化反应中非常有效。
