The abstraction of halogen atoms from alkyl halides by the trichlorosilyl radical

Abstract

By photolysis of alkyl halides in the presence of trichlorosilane a chain reaction is initiated in which the rate-determining step is the abstraction of a halogen atom from the alkyl halide by the trichlorosilyl radical. Relative rates of abstraction from alkyl halides have been measured in competitive experiments, and the following Arrhenius parameters obtained: [graphic omitted] The decreasing activation energy in the Table parallels decreasing bond-dissociation energy of the C–X bond.