AbstractFrom the copper-catalyzed reaction of germanium powder with dichloromethane at 350 °C a mixture of alkylchlorogermanes is obtained, in which CH3GeCl3, CH2(GeCl3)2 (1) and (Cl2GeCH2)3 (2) are the major products. Treatment of 1 and 2 with LiAlH4 in di-n-butyl or diethylether, resp., affords the hydrides CH2(GeH3)2 (3) and cyclic (H2GeCH2)3 (4), the latter along with the heterocycle H2Ge(CH2GeH2)2 (5). Compounds 3-5 have been identified by analytical and spectroscopic data, and the crystal structure of 4 has been determined by single crystal X-ray diffraction. The compound crystallizes in the orthorhombic space group Pmn21, with two molecules in the unit cell (a = 8.663(1), b = 7.783(1), c = 6.124(1) Å). The molecules, which are in a chair conformation, have crystallographic mirror symmetry with bond angles slightly larger than tetrahedral and Ge-C distances of 1.944(6), 1.953(3) and 1.955(4) Å. The compounds show potential as substrates for plasma-enhanced chemical vapour deposition (PE-CVD) of amorphous germanium carbon alloys (a-Ge, C:H).

Reaction of germanium powder and Cl3SiCH2Cl at 350 °C yields the l-germa-3-silapropane Cl3SiCH2GeCl3, and (Cl3SiCH2)2GeCl2, in a “Direct Synthesis”. Cl3GeCH2CH2GeCl3 is obtained from HGeCl3 and C2H2 as a “Hydrogermylation” product. Addition of CH2=CHSiCl3 to HGeCl3 yields the 1-germa-4-silabutane Cl3SiCH,CH2GeCl3, and Cl3GeCH2C(GeCl3)=CH2 is obtained similarly from ClCH2C=CH and HGeCl3-NEt3. These Chlorogermanes or -germanes/silanes are converted into the corresponding germanes (silanes) by treatment with LiAlH4 in tetralin as a solvent in the presence of triethyl(benzyl)ammonium chloride. The products are isolated in high yields and identified by standard analytical techniques, including 73Ge NMR spectroscopy. Owing to their high volatility they are potential feed-stock gases for CVD experiments to generate a-GeC:H or a-Ge,Si,C:H materials.

A lkylbrom ogerm anes, Synthesis, C V D Feeding G as, G erm anium /Copper Mixtures From the copper-catalyzed reaction o f germanium powder with dibrom om ethane at 310 °C a mixture o f alkylbrom ogermanes is obtained. The major products are CH 3G eB r3, Br3G eC H 2Br

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265ChemInform Abstract The chlorinated precursors (III), (IV), (VII), (IX), and (XII) are prepared as shown and converted into the corresponding germanes and silanes (XIV) (yields 29/71%), (XV) (70/79%), and (XVI) (45%) by treatment with LiAlH4 in tetralin in the presence of triethyl(benzyl)ammonium chloride. Owing to their high volatility the products are potential feed-stock gases for CVD experiments to generate a-GeC:H or a-GeSiC:H materials.