Unusual Inhibition Effect of 1-(1-Naphthyl)-1-methylethylhydroperoxide on the Liquid-Phase Oxidation of Isopropylarenes. GC−MS and Theoretical Studies of the Thermal Decomposition of 1-Naphthyl- and 1-Anthryl-1-methylethylhydroperoxides

Abstract

All five possible 1-aryl-1methylethylhydroperoxides derived from naphthalene and anthracene were synthesized and their thermal decomposition in GC−MS conditions was investigated to explain the unusual inhibition effect of 1-(1-naphthyl)-1-methylethylhydroperoxide on the liquid-phase oxidation of isopropylarenes. 2-(1-Aryloxy)propenes were identified as the main decomposition products of 1-(1-naphthyl)-1-methylethylhydroperoxide and 1-(1-anthryl)-1-methylethylhydroperoxide. The relatively unstable 2-aryloxypropenes have thus far never been described as thermal decomposition products of 1-aryl-1-methylethylhydroperoxides. The plausible mechanism of the formation of 2-(1-aryloxy)propenes was proposed on the basis of AM-1 calculations of the possible rearrangement paths of the alkoxy radicals derived from the investigated hydroperoxides. The mechanism explains the inhibition effect of 1-(1-naphthyl)-1-methylethylhydroperoxide on the oxidation of isopropylarenes.