NMR Spectra of Organogermanium Compounds. X. Syntheses,13C and73Ge NMR Spectra and Molecular Mechanics Calculations of Germacyclopentanes and Germacyclopentenes
Preparation and Some Reactions of Diarylgermylenedialkali Metals
作者:Kunio Mochida、Naoki Matsushige、Mari Hamashima
DOI:10.1246/bcsj.58.1443
日期:1985.5
The reactions of diarylgermanes with alkali metals in HMPA/THF or THF were found to give the corresponding diarylgermylenedialkali metals in high yields. Diphenylgermylenedipotassium reacted with aryl halides or carbonyl compounds to give reduction products predominantly. With alkyl halides, diphenylgermylenedipotassium gave mainly substitution products.
The enthalpy of formation of 1,1-diphenylgermanocyclopentane and an assessment of the strain in the ring system
作者:A.S Carson、J Dyson、P.G Laye、J.A Spencer
DOI:10.1016/0021-9614(88)90036-5
日期:1988.12
burnt in an aneroid combustion bomb and the enthalpy of sublimation measured by a combination of d.s.c. and effusion: Δ f H m o (C 6 H 5 ) 2 Ge(CH 2 ) 4 , cr} = (34.3 ± 10.0) kJ · mol −1 ; Δ f H m o (C 6 H 5 ) 2 Ge(CH 2 ) 4 , g} = (138.9 ± 10.5) kJ · mol −1 . The gas-phase molar enthalpy of formation has been used to investigate strain in the ringsystem.
摘要 化合物 (C 6 H 5 ) 2 Ge(CH 2 ) 4 已在无液燃烧弹中燃烧,并通过 dsc 和 effusion 组合测量升华焓:Δ f H mo (C 6 H 5 ) 2 Ge(CH 2 ) 4 , cr} = (34.3 ± 10.0) kJ·mol -1 ;Δ f H mo (C 6 H 5 ) 2 Ge(CH 2 ) 4 , g} = (138.9 ± 10.5) kJ·mol -1 。气相摩尔生成焓已用于研究环系统中的应变。
A dirhodium-catalyzed, β-selective C-H amination of organosilicon compounds has been developed. Primary C(sp3)-H bonds of silylethyl groups and secondary C(sp3)-H bonds of silacycloalkanes can be selectively converted to C-N bonds at the β-position of the silicon atoms. The experimental data and theoretical calculations indicate that the strong σ-donor ability of the carbon-silicon bonds is responsible
NMR Spectra of Organogermanium Compounds. X. Syntheses,<sup>13</sup>C and<sup>73</sup>Ge NMR Spectra and Molecular Mechanics Calculations of Germacyclopentanes and Germacyclopentenes
Germacyclopentane, its 1-methyl, and 1,1-dimethyl derivatives together with some germacyclopentenes were prepared and their 13C and 73Ge NMR spectra were determined. Molecular mechanics calculations of germacyclopentanes indicate that the symmetric twist form is the most stable in contrast to cyclopentane where the envelop and twist forms have much the same energy. Though both 13C and 73Ge chemical shifts are less sensitive to the stereochemistry of the methyl group as compared with the corresponding germacyclohexanes, the spectroscopic results can be explained in terms of the structures as depicted by molecular mechanics calculations.