Syntheses, Structures, and Electronic Properties of the Branched Oligogermanes (Ph3Ge)3GeH and (Ph3Ge)3GeX (X = Cl, Br, I)

The branched oligogermanium hydride (Ph3Ge)3GeH was synthesized via a hydrogermolysis reaction from GeH4 and Ph3GeNMe2 and was converted to the halide series of compounds (Ph3Ge)3GeX (X = Cl, Br, I) upon reaction with [Ph3C][PF6] in CH2X2 solvent (X = Cl, Br, I). These species were fully characterized by NMR (1H and 13C) and UV/visible spectroscopy, cyclic voltammetry, and elemental analysis. In addition, (Ph3Ge)3GeH was analyzed by 73Ge NMR spectroscopy and exhibits two resonances at δ −56 and −311 ppm. A Ge−H coupling constant of 191 Hz was observed in the proton-coupled 73Ge NMR spectrum of (Ph3Ge)3GeH. The X-ray crystal structures of (Ph3Ge)3GeH and (Ph3Ge)3GeX (X = Cl, Br, I) were obtained and represent the first examples of branched oligogermane hydrides or halides to be characterized in this fashion. The Ge−Ge bond distances in (Ph3Ge)3GeH are short (average value 2.4310(5) Å), while those in the halide compounds (Ph3Ge)3GeX are similar to one another and range from 2.4626(7) to 2.4699(5) Å. The UV/visible and cyclic voltammetry data for these species have been correlated with DFT computations, and excellent agreement was found between the experimental and theoretical data.

以氢化反应从GeH4与Ph3GeNMe2出发合成的支链寡锗氢化物（(Ph3Ge)3GeH）经过与[Ph3C][PF6]在CH2X2溶剂（X = Cl, Br, I）中的反应，转化为了一系列卤化物化合物（(Ph3Ge)3GeX，X = Cl, Br, I）。这些物质通过核磁共振（1H和13C）、紫外-可见光谱、循环伏安法和元素分析进行了全面表征。此外，（Ph3Ge）3GeH通过73Ge核磁共振光谱进行了分析，展现出在δ −56和−311 ppm处的两个共振峰。在（Ph3Ge）3GeH的质子偶合73Ge核磁共振光谱中观察到Ge−H偶合常数为191 Hz。获得了（Ph3Ge）3GeH和（Ph3Ge）3GeX（X = Cl, Br, I）的X射线晶体结构，这代表了首次以这种方式表征的支链寡锗氢化物或卤化物。在（Ph3Ge）3GeH中，Ge−Ge键长较短（平均值为2.4310(5) Å），而在卤化物化合物（Ph3Ge）3GeX中，这些键长彼此相似，范围在2.4626(7)至2.4699(5) Å之间。这些物质的紫外-可见光谱和循环伏安法数据与DFT计算进行了关联，实验数据与理论数据之间表现出卓越的一致性。