Coordination Chemistry of Reactive Homoleptic Acetonitrile Complexes with an Unusual Bulky Alkoxo-Phosphine Ligand

无机化学、生物无机化学和金属有机化学项目的目标是发展以非水溶剂分子为唯一配体的铂和铑等金属的络合离子的化学。预计溶剂分子可以很容易地从金属中置换出来，从而可以合成不能以通常的方法从金属氯化物开始制备的络合物。将合成的新化合物将作为有机化合物合成的催化剂或试剂具有潜在的价值。以乙腈等非水溶剂分子为配体的络合物将作为合成配体缺乏络合物的起始材料。溶剂络合物将由卤化物络合物在Sigma给体溶剂(如乙腈)的存在下与卤化物抽提剂(如六氟磷酸铊或四苯基硼酸钠)反应得到。将探索这些溶剂络合物与一种不寻常的磷化氢--三(2，4，6-三甲氧基苯基)膦，TMPP的反应。初步结果表明，由于TMPP配体的立体结构，可以得到只有两个TMPP分子与阳离子结合的同质络合物。这些配位不饱和的动力学产物有望表现出很高的反应活性，特别是在金属中心对小底物攻击的敏感性方面。人们将尝试制备TMPP的低价过渡金属络合物，以便这些络合物可以用于探索一氧化碳、二氧化碳、氮气和氢气等小分子的结合和潜在的激活。

The aim of this project in the Inorganic, Bioinorganic and Organometallic Chemistry program is to develop the chemistry of complex ions of such metals as platinum and rhodium with non-aqueous solvent molecules as the only ligands. It is expected that the solvent molecules be can displaced easily from the metal, allowing the synthesis of complexes which cannot be prepared in the usual way starting with the metal chlorides. The new compounds which will be synthesized will have potential value as catalysts or as reagents for the synthesis of organic compounds. Complexes with non-aqueous solvent molecules, such as acetonitrile, as ligands will be explored as starting materials for the synthesis of ligand-deficient complexes. The solvent complexes will be obtained from halide complexes by reaction with halide abstraction reagents, such as thallium hexafluoro- phosphate or sodium tetraphenylborate, in the presence of a sigma-donor solvent, such as acetonitrile. Reactions of these solvent complexes with an unusual phosphine, tris(2,4,6-trimethoxyphenyl)phosphine, TMPP, will be explored. Preliminary results indicate that homoleptic complexes with only two TMPP molecules bound to the cation can be obtained, due to the steric bulk of the TMPP ligand. These coordinatively unsaturated kinetic products are expected to exhibit high reactivity, especially with regard to susceptibility of the metal center toward attack by small substrates. Attempts will be made to prepare low-valent transition metal complexes of TMPP, so that these complexes may be used to probe the binding and potential activation of small molecules such as carbon monoxide, carbon dioxide, dinitrogen and dihydrogen.