Asymmetric hydrogenation of alpha-keto acid derivatives by rhodium-{amidophosphine-phosphinite} catalysts
Asymmetric hydrogenation of alpha-keto acid derivatives by rhodium-{amidophosphine-phosphinite} catalysts
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DOI：
10.1016/s0957-4166(97)00078-5
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发表时间：
1997-04-11
影响因子：
--
通讯作者：
Mortreux, A
中科院分区：
文献类型：
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作者：
Carpentier, JF;Mortreux, A
研究了几种α -酮酯（3a-f, 5a-j）， α -酮酰胺（7a-e）和异嘌呤衍生物（9a-d）在四种代表性中性均相铑-氨基膦-亚膦酸盐催化剂上的对映选择性加氢反应。与大多数芳族α -羟基酯6a-j （8-81% ee）相比，三氟乙酸- rh - ampp催化前体促进了脂肪族α -羟基酯4a-f的快速、高效合成，其对映选择性中至高（66-95% ee）。对-羟基酰胺8a-e （85-95% ee）和二氧化吲哚10a-d （80-94% ee）的对映选择性最好。本文提出，与α -酮类酰胺相反，α -酮类酯不会螯合到铑中心，在这种情况下，不对称诱导主要由C=O函数周围的位阻控制。1997爱思唯尔科学有限公司
The enantioselective hydrogenation of several alpha-keto esters (3a-f, 5a-j), alpha-keto amides (7a-e) and isatine derivatives (9a-d) with a set of four representative neutral homogeneous rhodium-amidophosphine-phosphinite catalysts has been investigated. Trifluoroacetato-Rh-AMPP catalytic precursors promoted the rapid, efficient synthesis of aliphatic oc-hydroxy esters 4a-f in moderate to high enantioselectivities (66-95% ee), in contrast to most aromatic alpha-hydroxy esters 6a-j (8-81% ee). Best enantioselectivities for alpha-hydroxy amides 8a-e (85-95% ee) and dioxindoles 10a-d (80-94% ee) were obtained with chloro-Rh-AMPP precursors. It is proposed that, contrary to alpha-keto amides, alpha-keto esters do not chelate onto the rhodium center and that, in such circumstances, the asymmetric induction is mainly controlled by the steric hindrance around the C=O function. (C) 1997 Elsevier Science Ltd.