The catalytic hydration of nitriles to amides using a homogeneous platinum phosphinito catalyst
The catalytic hydration of nitriles to amides using a homogeneous platinum phosphinito catalyst
复制标题
DOI：
10.1016/s1381-1169(00)00253-3
复制
发表时间：
2000-10-31
影响因子：
--
通讯作者：
Parkins, AW
中科院分区：
文献类型：
--
作者：
Ghaffar, T;Parkins, AW
介绍了腈水合制酰胺的新型均相催化剂。催化剂前体是Pt（II）与仲氧化膦的配位化合物。它们含有氢桥连的单阴离子二齿膦基，以及第三氧化膦配体和单齿阴离子配体，氢化物或氯化物。使氯化物与银离子反应，或使氢化物与水反应，得到作为活性催化剂的阳离子物质。在与阳离子配位时，腈变得对亲核攻击敏感。水解得到酰胺作为唯一产物，并且没有进一步水解成酸的趋势。研究了取代基对磷的影响，并提出了反应机理。活性最高的催化剂[PtH（PMe2OH）（PMe2O）（2）H]，2a，衍生自二甲基氧化膦，该前体催化丙烯腈水合为丙烯酰胺，转化数为77，000，不添加C=C双键。(C)2000 Elsevier Science B.V.保留所有权利。
New homogeneous catalysts for the hydration of nitriles to amides are described. The catalyst precursors are coordination compounds of Pt(II) with secondary phosphine oxides. They contain a hydrogen bridged mono-anionic didentate phosphinito group, together with a third phosphine oxide ligand and a monodentate anionic ligand, either hydride or chloride. Reacting the chloride with silver ion, or the hydride with water gives a cationic species which is the active catalyst. On coordination to the cation the nitrile becomes susceptible to nucleophilic attack. The hydrolysis gives the amide as the sole product, and there is no tendency towards further hydrolysis to the acid. The effects of substituents on phosphorus are investigated, and a reaction mechanism is suggested. The most active catalyst, [PtH(PMe2OH)(PMe2O)(2)H], 2a, is derived from dimethylphosphine oxide, and this precursor catalyses the hydration of acrylonitrile to acrylamide with a turnover number of 77,000, without addition to the C=C double bond. (C) 2000 Elsevier Science B.V. All rights reserved.