Highly Enantioselective Rhodium-Catalyzed Hydrogenation of 2-(2-Methoxy-2-oxoethyl)acrylic Acid− A Convenient Access of Enantiomerically Pure Isoprenoid Building Blocks
作者:Markus Ostermeier、Bernhard Brunner、Christian Korff、Günter Helmchen
DOI:10.1002/ejoc.200300222
日期:2003.9
Asymmetric catalytic hydrogenation of 2-(2-methoxy-2-oxoethyl)acrylic acid (5) to give (2S)-4-methoxy-2-methyl-4-oxobutanoic acid [(S)-6] was studied. An enantiomeric excess of 99.7% ee was achieved with a catalyst formed in situ from [Rh(COD)2]BF4 and the chiral phosphite L2 in 1,2-dichloroethane as solvent. In addition, enzyme-catalyzed semi-saponification of dimethyl 2-methylsuccinate was investigated
研究了 2-(2-甲氧基-2-氧乙基) 丙烯酸 (5) 的不对称催化氢化得到 (2S)-4-甲氧基-2-甲基-4-氧代丁酸 [(S)-6]。使用由 [Rh(COD)2]BF4 和手性亚磷酸酯 L2 在作为溶剂中的 [Rh(COD)2]BF4 和手性亚磷酸酯 L2 原位形成的催化剂,实现了 99.7% ee 的对映体过量。此外,还研究了酶催化的 2-甲基琥珀酸二甲酯的半皂化反应。单酯 (S)-6 被转化为一些化合物,这些化合物可以作为天然产物合成中的 C5 结构单元。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)