Free-radical substitution in aliphatic compounds. Part XXVIII. The gas-phase bromination of halogenocyclohexanes and halogenocyclopentanes in a fast flow reactor

The bromination of fluoro-, chloro-, and bromo-cyclohexane and chloro- and bromo-cyclopentane has been investigated in the gas phase using a flow system. Unlike previous work in solution and in a static gas phase apparatus, normal directive effects were observed, and no olefinic products were obtained. These results suggest that the high yields of 1,2-dibromoalkanes reported previously in solution phase experiments are not due to 'anchimeric assistance' although 'bridging' by the substituent may be an important factor.