57482-41-4Relevant academic research and scientific papers
Synthesis of Triscyclopentadienyl(triphenylgermyl)uranium and Facile Isonitrile Insertion into the Uranium-Germanium Bond
Porchia, Marina,Ossola, Franco,Rossetto, Gilberto,Zanella, Pierino,Brianese, Nicola
, p. 550 - 551 (1987)
The uranium-germanium bonded complex (cp)3UGePh3 (1) (cp = η5-C5H5) has been prepared from (cp)3UCl and KGePh3 and fully characterized; it reacts readily with 2,6-dimethylphenyl isocyanide to give the carbamoyl insertion product (cp)3
Elucidation of the thermochemical properties of triphenyl- or tributyl-substituted Si-, Ge-, and Sn-centered radicals by means of electrochemical approaches and computations
Holm, Allan Hjarbaek,Brinck, Tore,Daasbjerg, Kim
, p. 2677 - 2685 (2007/10/03)
Redox potentials of a number of triphenyl- or tributyl-substituted Si-, Ge-, or Sn-centered radicals, R3M., have been measured in acetonitrile, tetrahydrofuran, or dimethyl sulfoxide by photomodulated voltammetry or through a study of the oxidation process of the corresponding anions in linear sweep voltammetry. For the results pertaining to the Ph 3M. series (including literature data for M = C), the order of reduction potentials follows Sn > Ge > C > Si, while for the two oxidation potentials, it is C > Si. The effect of the R group on the redox properties of R3Sn. is pronounced in that the reduction potential is more negative by 490 mV in tetrahydrofuran (390 mV in dimethyl sulfoxide) when R is a butyl rather than a phenyl group. The experimental trends have been substantiated through quantum chemical calculations, and they can be explained qualitatively by considering a combination of effects, such as charge capacity being most pronounced for the heavier elements, resonance stabilization present for the planar Ph 3C. and all R3M+, and finally a contribution from solvation. The solvation of R3M- is observed to be relatively strong because of a rather localized negative charge in the pyramidal geometry. However, there is no evidence in the calculations to support the existence of covalent interactions between solvent and anions. The solvation of R3M+ is relatively weak, which may be attributed to the planar geometry around the center atom, leading to more spread out charge than that for a pyramidal geometry. Although the calculated solvation energies based on the polarizable continuum model approach exhibit the expected trends, they are not able to reproduce the experimentally derived values on a detailed level for these types of ions. An evaluation of the general performance of the continuum model is provided on the basis of present and previous studies.
Ueber gemischte Gruppe 14-Gruppe 14-Bindungen. V. Sechs Perphenylierte Propan-Analoga Ph3M-M'Ph2-M''Ph3 (M, M', M'' = Si/Ge): ein Beitrag zum Elektronegativitaetsunterschied zwischen Silicium und Germanium
Charisse, Michael,Mathes, Manfred,Simon, Dietolf,Draeger, Martin
, p. 39 - 48 (2007/10/02)
The six title compounds have been synthesized from Li/K-Si/GePh3 and chloride precursors in THF, DMF or diethyl ether at low temperature.The six compounds crystallize isomorphously in the space group Pbca with ordered arrangement for the four symmetrical cases (Si-Si 2.394, Si-Ge 2.412, Ge-Ge 2.440 Angstroem) and statistical alignment for the two asymmetrical chains; angle range 116.6-123.3 deg.Replacement of Si by Ge atoms leads to low field NMR chemical shifts for 13Cipso atoms and for directly bonded 29Si atoms.This is in accordance with an enhanced electronegativity of germanium in comparison with silicon.UV/Vis and IR/Raman data are given.
