1066-63-3Relevant academic research and scientific papers
Photochemical Reactions of Vinyl-, Styryl- and Benzyl-Substituted Digermanes
Mochida, Kunio,Kikkawa, Haruhiko,Nakadaira, Yasuhiro
, p. 2772 - 2777 (2007/10/02)
Photochemical reactions of vinyl-, styryl- and benzyl-substituted digermanes by chemical trapping experiments.Photolysis of vinylpentamethyldigermane afforded 1-trimethyl-2-(pentamethyldigermyl)ethane as a major product, and styrylpentamethyldigermanes gave mainly styryltrimethylgermane.On the other hand, photolysis of benzyl-substituted digermanes (benzylpentamethyldigermane and 1,2-dibenzyltetramethyldigermane) gave hydrogermanes and hydrodigermanes as main products, respectively.These products were derived from germyl radicals generated by photoinduced homolysis of the germanium-germanium bond.In carbon tetra chloride (CCl4), these germyl radicals were converted to the corresponding chlorogermanes by abstraction of a chlorine atom.Germylene species were also to be evolved from such photolyses.
Photochemical reactions of aryl-substituted catenates of group 4B elements, PhMe2E-E'Me3 (E, E' = Si and Ge). Formation of a radical pair
Mochida, Kunio,Kikkawa, Haruhiko,Nakadaira, Yasuhiro
, p. 9 - 19 (2007/10/02)
Photochemical reactions of phenyl substituted catenates of group 4B elements, PhMe2E-E'Me3 (E, E' = Si and Ge) have been investigated by chemical trapping experiments and laser flash-photolysis.On irradiation, the phenylated group 4B catenate undergoes E-E' bond homolysis to give a pair of radicals (PhMe2E. and Me3E'.).In CCl4, these radicals are converted to the corresponding chlorides by abstraction of a chlorine atom.In a nonhalogenated solvent, the radical pair couples at the ipso-position of the phenyl group of the pairing radical (PhMe2E.) to yield the cor responding diradical.This undergoes either elimination of a divalent species (Me2E:) with concomitant formation of trimethylphenyl group 4B element PhMe3E') or intramolecular 1,2-group 4B element migration to yield group 4B metal-carbon double bonded species.The radical escapes from the solvent cage coupled to the metal atom of the radical to yield the dimetallic product.The reaction path observed is highly dependent on the nature of the group 4B element comprising the phenyl substituted catenate.
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.
