Heteroatom-Free Arene-Cobalt and Arene-Iron Catalysts for Hydrogenations
Heteroatom-Free Arene-Cobalt and Arene-Iron Catalysts for Hydrogenations
复制标题
DOI：
10.1002/anie.201308967
复制
发表时间：
2014-04-01
影响因子：
16.6
通讯作者：
Jacobi von Wangelin, Axel
中科院分区：
文献类型：
--
作者：
Gaertner, Dominik;Welther, Alice;Jacobi von Wangelin, Axel
在氢甲酰化被发现75年后，钴催化剂现在正在经历氢化反应的复兴。我们评估了低价金属物种-概念上不同于基于杂原子的配体-通过pi配位稳定到碳氢化合物的芳烃金属盐。双(蒽)钴酸钾1和-高铁酸钾2可以看作是准“裸”阴离子金属物种的合成前体；它们的聚集被不饱和分子(烯烃、芳烃、羰基化合物)加氢反应中存在的各种p受体(不稳定的)配位有效地阻止。烯烃加氢的动力学研究、核磁共振波谱和中毒研究支持形成均相催化剂，该催化剂是由烯烃配位稳定的。这一催化剂概念补充了具有杂原子给体配体的络合物在还原过程中的使用。
75 years after the discovery of hydroformylation, cobalt catalysts are now undergoing a renaissance in hydrogenation reactions. We have evaluated arene metalates in which the low-valent metal species is-conceptually different from heteroatom-based ligands-stabilized by pi coordination to hydrocarbons. Potassium bis(anthracene)cobaltate 1 and -ferrate 2 can be viewed as synthetic precursors of quasi-"naked" anionic metal species; their aggregation is effectively impeded by (labile) coordination to the various p acceptors present in the hydrogenation reactions of unsaturated molecules (alkenes, arenes, carbonyl compounds). Kinetic studies, NMR spectroscopy, and poisoning studies of alkene hydrogenations support the formation of a homogeneous catalyst derived from 1 which is stabilized by the coordination of alkenes. This catalyst concept complements the use of complexes with heteroatom donor ligands for reductive processes.