BENZOYL HYPOCHLORITE, AN INTERMEDIATE IN OXIDATION OF IONIC CHLORIDES AND HYDROGEN CHLORIDE BY BENZOYL PEROXIDE

The oxidation of chloride ion by benzoyl peroxide yields benzoyl hypochlorite. Free-radical initiation causes the decomposition of this intermediate to chlorobenzene, and in this and other reactions, the intermediate shows the same chemistry as the intermediate in the Hunsdiecker reaction. In the presence of an alkane, the acyl hypochlorite functions as a free-radical chlorinating reagent. Investigation of the mechanism of this reaction suggests that atomic chlorine is the chain-carrying species. When hydrogen chloride is oxidized by benzoyl peroxide in the absence of an alkane, only traces of chlorobenzene are produced. This is attributed to the rapid reaction of hydrogen chloride with the acyl hypochlorite to give molecular chlorine. In the presence of an added hydrocarbon, the chlorine so formed yields alkyl chlorides by a free-radical process, the mechanism of which is complicated by the reversible reaction of the intermediate alkyl radicals with the hydrogen chloride in the system. © 1969, American Chemical Society. All rights reserved.