No abstract

The trimerization of acetylene (3) and the cycloaddition of 3 with formylketene (8) are two examples of CT,jr-aromatizations. The cycloaddition of ethylene and 8 completes the same cr-system as the

No abstract

Low-temperature photolysis of tris(trimethylsilyl)silane derivatives in a 3-methylpentane glass at 77 K yields hexamethyldisilane and trimethylsilyl-substituted silylenes. These silylenes exhibit broad n ~ p absorptions at wavelengths typically > 600 nm in the UV and have been captured by 2,3-dimethylbutadiene in cyclohexane at room temperature. Exceptions to the usual position of Ama x have been observed and are discussed.

1991organo-silicon compounds, nonmetal heterocycles organo-silicon compounds, nonmetal heterocycles S 0067 -195Addition of Dimesitylsilylene to Olefins. A Reinvestigation.-Contrary to an earlier report it is shown that the title addition is highly stereospecific. The siliranes are obtained with ¿ 98% retention of the configuration. The acyclic isomers are by-products, which become the major products on further photolysis. A probable explanation for the earlier work is given. -(ZHANG, S.; WAGENSELLER, P. E.; CONLIN, R. T.; J. Am. Chem. Soc. 113 (1991) 11, 4278-4281; Dep. Chem., Univ. N. Tex., Denton, TX 76203, USA; EN)