Reactions of radicals containing fluorine. Part 4.—Reactions of trifluoromethyl radicals with fluoroaldehydes

Abstract

The reactions of trifluoromethyl radicals, generated by the photolysis of hexafluoroacetone, with the aldehydes HCOCF₃, HCOC₂F₅ and HCOC₃F₇ have been studied and the following Arrhenius parameters determined : [graphic omitted] The rate of hydrogen atom abstraction from the fluoroaldehydes at 164°C is independent of the size of the fluoroalkyl group. Direct photolysis of the aldehydes HCOCF₃, HCOC₂F₅ and HCOC₃F₇ is complicated by the intramolecular elimination reactions : [graphic omitted] A value of 1.95, which is independent of temperature, has been obtained for the cross-combination of CF₃ and C₂F₅ radicals.