5764-66-9Relevant articles and documents
Photochemistry of group 14 1,1,1-trimethyl-2,2,2-triphenyldimetallanes (Ph3MM′Me3; M, M′ = Si, Ge). Direct detection and characterization of silene and germene reactive intermediates
Leigh, William J.,Toltl, Nicholas P.,Apodaca, Paula,Castruita, Madeli,Pannell, Keith H.
, p. 3232 - 3241 (2008/10/08)
The photochemistry of trimethylsilyltriphenylgermane (Ph3GeSiMe3), triphenylsilyltrimethylgermane (Ph3SiGeMe3), and 1,1,1-trimethyl-2,2,2-triphenyldigermane (Ph3GeGeMe3) has been studied in hydrocarbon solution by steady state and laser flash photolysis methods and is compared to previously reported data for the homologous disilane Ph3SiSiMe3. A variety of products are formed upon photolysis of the three compounds in the presence of 2,3-dimethyl-1,3-butadiene or chloroform, but in each case the major ones are derived from M-M′ bond homolysis and dimethyl- or diphenylgermylene extrusion. The trapping products of the 1,3,5-(1-metalla)hexatriene derivatives formed by [1,3]-MMe3 migration into the ortho-position of one of the phenyl rings are formed as well, in yields of 9-30%. While these experiments indicate that germylenes are formed in at least twice the yield of the 1,3,5-(1-metalla)hexatrienes, only the latter and triphenylsilyl or triphenylgermyl radicals can be detected by laser flash photolysis techniques. The metallaenes have been identified on the basis of their time-resolved UV absorption spectra and absolute rate constants for reaction with 2,3-dimethylbutadiene, methanol, acetone, acetic acid, oxygen, and carbon tetrachloride and can be distinguished from germylenes by their lack of reactivity toward triethylsilane and chloroform. Radical formation is shown to result from reaction of the triplet states of these compounds, and a triplet lifetime is estimated for Ph3GeSiMe3 and compared to that of the disilane homologue. The results of time-resolved experiments on other, related compounds are discussed in light of these results.
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.
Photochemistry of aryl-substituted trigermanes. Generation and mechanism of formation of germylenes
Mochida, Kunio,Yoneda, Isao,Wakasa, Masanobu
, p. 53 - 62 (2007/10/02)
Photochemical reactions of aryl-substituted trigermanes have studied by trapping experiments, matrix isolation, and laser flash-photolysis techniques.Photolysis of the phenylated trigermanes involved both the simple extrusion of germylenes and the formati
