New photochemical routes to germylenes and germenes and kinetic evidence concerning the germylene-diene addition mechanism

Article abstract of DOI:10.1021/om00054a046

Upon 254-nm irradiation of phenylbis(trimethylsilyl)germanes, there is competition between two germylene-forming reactions, the unexpected elimination of phenyltrimethylsilane and the elimination of hexamethyldisilane. Irradiation of a phenylmonosilylgermane PhGeMe₂SiMe₃ leads to predominant elimination of PhSiMe₃, forming dimethylgermylene Me₂Ge:, accompanied by migration of Me₃Si to the ortho position of the phenyl ring, forming a germene. Laser flash photolysis of PhGeMe₂SiMe₃ is a convenient source of Me₃Ge:, and rate constants are reported for Me₂Ge: addition to a series of dienes and other substrates. The kinetic data are in accord with 1,2-addition as the dominant pathway for addition of Me₂Ge: to 1,3-dienes.