22702-77-8Relevant academic research and scientific papers
Molecular structures of the digermanes Me2XGeGeXMe2 (X = Me, Cl, and H): An ab initio study combined with experimental investigation by raman spectroscopy and gas electron diffraction
Hoelbling, Margit,Masters, Sarah L.,Flock, Michaela,Baumgartner, Judith,Hassler, Karl,Robertson, Heather E.,Wann, Derek A.
, p. 3023 - 3033 (2009/02/02)
Ab initio calculations were carried out to investigate the potential-energy surface for internal rotation of the methylated digermanes hexamethyldigermane Me3GeGeMe3 (1), dichlorotetramethyldigermane Me 2ClGeGeClMe2 (2), and tetramethyldigermane Me 2HGeGeHMe2 (3). Different basis sets [6-31+G(d), SDD, aug-cc-pVTZ] were employed at the DFT and MP2 levels of theory to optimize structures and to calculate energies and vibrational frequencies. For 1, one minimum representing a staggered structure was located on the potential-energy surface. For 2 and 3, antiperiplanar conformations with C2 symmetry were found to be the global minima. Additionally, synclinal minima were located for 2 and 3 when certain basis sets were employed. Determination of structural parameters in the gas phase by gas electron diffraction confirmed the computed predictions for all three compounds. For 2 and 3, the ratios of antiperiplanar to synclinal conformer were detected to be 90:10 (328 K) and 72:28 (293 K), respectively, by gas electron diffraction. The experimentally determined GeGe bond lengths in 1, 2, and 3 in the gas phase are 241.4(1), 242.7(2) (averaged for antiperiplanar and synclinal), and 241.7(1) pm (equal for antiperiplanar and synclinal). Only averaged structures were observed, using Raman spectroscopy, for 2 and 3 because the wavenumber differences are small between conformers and there is only a small contribution from the second conformer in each case. For 2, the crystal structure was also determined by X-ray diffraction. An anticlinal structure (with Cl atoms eclipsing the C atoms) was found with a GeGe bond length of 242.1 pm.
Studies of photochemical reactions of 7,8-digermabicyclo[2.2.2]octadienes by steady-state and laser flash photolysis techniques
Mochida, Kunio,Kayamori, Takanari,Wakasa, Masanobu,Hayashi, Hisaharu,Egorov, Mikhail P.
, p. 3379 - 3386 (2008/10/08)
The photochemistry of 1,4-diphenyl-2,3-benzo-7,7,8,8-tetraalkyl-7, 8-digermabicyclo[2.2.2]-octadienes in solution has been studied in detail by steady-state, nanosecond laser flash photolysis, and matrix isolation techniques. Photolysis of 7,8-digermabicy
Digermylplatinum(II) organometallic rings L2PtGe(Me2)EGeMe2 [E = N-, O, S, (η-C5H4)2Fe]
Barrau,Rima,Cassano,Satgé
, p. 5700 - 5703 (2008/10/09)
The synthesis, reactivity, and characterization of the digermylplatinum(II) linear complexes (ClMe2Ge)2Pt(PPh3)2 (1) and (ClMe2Ge)2Pt(diphos) (2) and cyclic complexes (diphos)PtGe-(Me2)EGeMe2 [E = S (3), -NPh (4), (η5-C5H4)Fe(η5-C 5H4) (5), O (6)] are reported. The chemistry of 2-6 is illustrated through their reactions with phenylacetylene and N-methyltriazolinedione. Complexes 3 and 6 give double germylation of these unsaturated systems, while 2, by reaction with triazolinedione, gives the monogermylated complex Me2-(Cl)GePt(Cl)diphos and the dimer of the germylated heterocycle Me2GeNC(O)N(Me)C(O)N.
Chemistry of heavy carbene analogues R2M (M = Si, Ge, Sn). 12. Concerted and nonconcerted insertion reactions of the germylene Me2Ge into the carbon-halogen bond
K?cher, Jürgen,Lehnig, Manfred,Neumann, Wilhelm P.
, p. 1201 - 1207 (2008/10/08)
During the reaction of Me2Ge with CCl3X (X = Cl, Br), PhCH2X (X = Br, I), and Ph2CHCl, 1H CIDNP is observed in the products of net insertion of Me2Ge into the carbon-halogen bond and in Me2GeX2 (X = Cl, Br). It is concluded that a two-step radical reaction takes place by an abstraction-recombination mechanism. No reaction takes place with alkyl halides that have a C-X bond dissociation energy of more than about 70 kcal/mol. Me2Ge is generated thermally at 70-95°C or photochemically from the 7-germabenzonorbornadiene 1 and reacts in both cases in the singlet state. The activation energy for forming Me2Ge from 1 is 19 kcal/mol for the reaction with CCl4. Insertion products are also formed with the alkenyl halides CH2=CHCH2X, PhCH=CHX (X = Cl, Br), and 2-bromobut-2-ene, but without showing CIDNP effects. Since Me2GeX2 was not found either, Me2Ge reacts in these cases in a nonradical manner. It does not react with 1-chlorocyclohexene, but it does react with Me2GeX2 under formation of digermanes and/or oligogermanes without CIDNP.
Dithiaphosphagermetannes-1,3,2,4 et dithiaphosphadigermolannes-1,4,5,2,3
Barrau, J.,Amine, M. El,Rima, G.,Satge, J.
, p. 615 - 620 (2007/10/02)
The synthesis of the new germylated and phosphorylated heterocycles 2-anisyl-4,4-dimethyl-2-thio-1,3,2,4-dithiaphosphagermetane, (1), and 5-anisyl-2,2,3,3-tetramethyl-5-thio-1,4,5,2,3-dithiaphosphadigermolane, (2), are described.The decomposition of 1 with formation of (Me2GeS)3 and (AnPS2)n is observed at room temperature.At 200 deg C 2 undergoes thermal fragmentation leading to (Me2GeS)3 and (AnPS)n.These results are explained by two mechanisms of decomposition involving formation of transient species and or , respectively.Exchange reactions between 2 and various metal (MIVB) chlorides are described.With Me2SiCl2 the reaction leads to silathione , probably via transient dithiaphosphasiletane.
THERMOLYSE ET PHOTOLYSE D'HETEROCYCLES A LIAISON Ge-S. MISE EN EVIDENCE DE LA FORMATION DE GERMYLENES ET GERMATHIONES
Barrau, J.,Amine, M. El,Rima, G.,Satge, J.
, p. 323 - 334 (2007/10/02)
The photolysis and thermolysis of 2,3-digerma-1,4-dithianes, 2,3,5-trigerma-1,4-dithiolanes and tetragerma-1,4-dithianes have been studied. 2,2,3,3-Tetramethyl-2,3-digerma-1,4-dithiane (I) decomposes slowly at room temperature by α-elimination to yield di
