Reactivity of [1],[1]Disilamolybdenocenophane toward Zerovalent Platinum Complexes

The results of studies of the reactivity of strained [1],[1]disilamolybdenocenophane toward zerovalent platinum complexes are reported. Whereas [Pt(PEt3)3] underwent clean insertion into both Si−Cispo bonds of the twofold-bridged molybdenocene, the reaction with the tricyclohexylphosphine analogue is considerably more complex. Thus, treatment of the molybdenum compound with 2 equiv of [Pt(PCy3)2] results in a trinuclear cluster. To gain insight into the mechanistic aspects, the reaction was performed in a 1:1 stoichiometry. Multinuclear NMR spectroscopy revealed the presence of different species in solution. Two constitutional isomers were identified by X-ray diffraction analyses, one presumably depicting an intermediate in the formation of the trinuclear cluster. The predominant isomer in solution was identified as the product of C−H oxidative addition to the platinum phosphine fragment. Its solid-state structure displays an unusual coordination mode of platinum, and structural parameters suggest the formulation as the σ-complex of a Mo−Si bond.

本研究报告了针对应力位错[1],[1]二硅钼酰苯对零价铂配合物的反应性研究。在[Pt(PEt3)3]中，铂配合物得以顺利插入双桥连钼ocene的双Si-Cispo键中，而与三环己基膦类似物的反应则显得相当复杂。因此，将钼化合物与2摩尔当量的[Pt(PCy3)2]处理，结果生成了三核簇。为了深入了解反应机理，反应以1:1的化学计量比进行。多核核磁共振波谱揭示了溶液中存在不同物种。通过X射线衍射分析确定了两种构型异构体，其中一种可能描绘了三核簇形成过程中的中间体。溶液中的主要异构体被确认为铂膦片段C-H氧化加成的产物。其固态结构展示了铂的不寻常配位模式，结构参数暗示了其为Mo-Si键的σ-复合物。