Homolytic Chlorination of Aliphatic Compounds. IV. Chlorination of Chloroalkanes by t-Butyl Hypochlorite

Abstract

Abstract Chlorination of chloroalkanes by t-butyl hypochlorite was investigated by means of competitive experiment. Relative reactivities thus obtained were compared with those toward hydrogen abstraction by t-butoxy radicals derived from other sources. From the results it was concluded that a main chain carrier of this chlorination was a t-butoxy radical. Structure-reactivity relationships in t-butyl hypochlorite chlorination were also investigated. Linear free energy relationship was found to exist between the reactivities of methyl hydrogen of CH3-X and Taft’s σ* constants for the substituent X,ρ*=−0.69. α-Chlorine substituents were found always to enhance the rate of hydrogen abstraction of this position. Resonance effects of a-chlorine substituent is considered to be more important than in photochlorination with chlorine.