Ellis John E
Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Inorg Chem. 2006 Apr 17;45(8):3167-86. doi: 10.1021/ic052110i.
A brief history of substances containing s,p- and d-block metals in negative oxidation states is described. A classification of these species and discussions of formal oxidation state assignments for low-valent transition metals in complexes are included, along with comments on the innocent and noninnocent character of ligands in metalates. Syntheses of highly reduced carbonyl complexes formally containing transition metals in their lowest known oxidation states of III- and IV- are discussed. Atmospheric-pressure syntheses of early-transition-metal carbonyls involving alkali-metal polyarene-mediated reductions of non-carbonyl precursors have been developed. In the absence of carbon monoxide, these reactions afford homoleptic polyarenemetalates, including the initial species containing three aromatic hydrocarbons bound to one metal. In several instances, these metalates function as useful synthons for "naked" spin-paired atomic anions of transition metals.
本文描述了含有处于负氧化态的s、p和d区金属的物质的简史。包括这些物种的分类以及对配合物中低价过渡金属形式氧化态归属的讨论，同时还对金属酸盐中配体的非活性和活性特征进行了评论。讨论了形式上含有处于其已知最低氧化态III和IV的过渡金属的高度还原羰基配合物的合成。已经开发了涉及碱金属多芳烃介导的非羰基前体还原的早期过渡金属羰基化合物的大气压合成方法。在没有一氧化碳的情况下，这些反应生成同配多芳烃金属酸盐，包括最初含有与一个金属结合的三个芳烃的物种。在一些情况下，这些金属酸盐可作为过渡金属“裸”自旋配对原子阴离子的有用合成子。
