Reactions of trichlorogermane HGeCl3 and dichlorogallane HGaCl2 with pyridine donors
Reactions of trichlorogermane HGeCl3 and dichlorogallane HGaCl2 with pyridine donors
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三氯锗烷 HGeCl3 和二氯没食子素 HGaCl2 与吡啶供体的反应
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
H. Schmidbaur
中科院分区：
文献类型：
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作者：
S. Nogai;A. Schriewer;H. Schmidbaur
发现弱碱吡啶使三氯根酸HGeCl3脱质子，定量生成三氯根酸吡啶（II）， Py-H+GeCl3−，阴离子的锥体结构类似于等电子AsCl3分子。与三氯硅烷HSiCl3中的（+）Si-H（−）键相比，HGeCl3中的键具有逆极化（−）Ge-H(+)，而三氯硅烷HSiCl3与吡啶形成1∶2的加合物。四氯化锗也与吡啶发生简单加成反应，最终与L = 4-乙基吡啶生成GeCl4L2。二氯大allane与L =吡啶、4-二甲氨基吡啶、4-氰吡啶和3,5-二甲基吡啶加成1∶1加成化合物（HGaCl2L），用单晶x射线衍射测定了它们的分子结构。取代基在镓中心周围的简单四面体排列，只有轻微的畸变，红外光谱中的Ga-H拉伸振动特征表明，Ga-H键在加成反应中没有受到影响。在HGaCl2中加入两个等量的3,5-二甲基吡啶，得到1∶2的配合物，该配合物具有三角-双锥体的几何结构，氢化物配体位于赤道位置。制备了L = 3,5-二甲基吡啶的1∶1加合物gaacl3 (L)和GaH3(L)，并对其结构进行了表征。四氯没食子酸吡啶（III）吸收吡啶，但额外的配体通过氢键连接到阳离子上，使阴离子保持不变：[Py- h⋯Py]+[GaCl4]−。
The weak base pyridine has been found to deprotonate trichlorogermane HGeCl3 with quantitative formation of pyridinium trichlorogermanate(II), Py-H+GeCl3−, the pyramidal structure of the anion resembling that of the isoelectronic AsCl3 molecule. This course of the reaction supports the assignment of an inverse polarization (−)Ge–H(+) of the bond in HGeCl3 as compared to the (+)Si–H(−) bond in trichlorosilane HSiCl3, which is known to form a 1 ∶ 2 adduct with pyridine instead. Germanium tetrachloride also undergoes simple addition reactions with pyridine leading ultimately e.g. to GeCl4L2 with L = 4-ethyl-pyridine. Dichlorogallane gives 1 ∶ 1 addition compounds (HGaCl2L) with L = pyridine, 4-dimethylamino-pyridine, 4-cyano-pyridine, and 3,5-dimethyl-pyridine, the molecular structures of which have been determined by single crystal X-ray diffraction. Simple tetrahedral arrays of substituents around the gallium center with only minor distortions, and characteristic Ga–H stretching vibrations in the IR spectra, show that the Ga–H bond is untouched in the addition reactions. The addition of two equivalents of 3,5-dimethyl-pyridine to HGaCl2 affords the 1 ∶ 2 complex which was shown to have a trigonal-bipyramidal geometry with the hydride ligand in an equatorial position. In order to provide benchmark data, the 1 ∶ 1 adducts GaCl3(L) and GaH3(L) with L = 3,5-dimethyl-pyridine were also prepared and structurally characterized. Pyridinium tetrachlorogallate(III) takes up pyridine, but the extra ligand is attached to the cation via hydrogen bonding leaving the anion unchanged: [Py-H⋯Py]+[GaCl4]−.