The enantioselective hydrogenation of methylacetoacetate over nickel catalysts modified with tartaric acid.
The enantioselective hydrogenation of methylacetoacetate over nickel catalysts modified with tartaric acid.
复制标题
酒石酸改性镍催化剂上乙酰乙酸甲酯的对映选择性加氢。
DOI：
10.1016/0920-5861(91)80017-4
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发表时间：
1991
期刊：
影响因子：
5.3
通讯作者：
G. Webb
中科院分区：
文献类型：
--
作者：
A. Bennett;S. Christie;M. Keane;R. Peacock;G. Webb
报道了在改性雷尼镍和二氧化硅负载镍催化剂上，前手性β-酮酯(甲基乙酰乙酸酯)对映体选择性氢化成β-羟基酯(3-羟基丁酸甲酯)的结果。考察了改性过程中pH、酒石酸浓度和NaBr的存在对反应的影响，以及酒石酸的吸附量与各种催化剂的转化率和对映体选择性的关系。描述了酒石酸与镍表面的相互作用对表面腐蚀性浸出的影响。为了优化镍体系的对映体选择性，考察了反应过程和修饰条件对产物酯的总体光学产率的影响。结果揭示了在这些体系中影响对映体选择性的相互关联因素的一般复杂性。
Results are reported for the enantioselective hydrogenation of a prochiral β-keto ester (methylacetoacetate) to a β-hydroxy ester (methyl-3-hydroxybutyrate) over modified Raney nickel and silica-supported nickel catalysts. The effects of variations in the modification procedure, that is pH, tartaric acid concentration and the presence of NaBr have been examined and the amount of tartaric acid adsorbed correlated with the conversion and enantioselectivity of the various catalysts. The effects of the interaction of tartaric acid with the nickel surface in terms of corrosive leaching from the surface are described. The influence of reaction procedures and modification conditions on the overall optical yield of the product ester have been investigated with a view to the optimisation of enantioselectivity in the nickel system. The results reveal the generally complex nature of the interrelated factors which influence enantioselectivity in these systems.