Mechanism for Diacyl Peroxide Decomposition

Article abstract of DOI:10.1021/jo00133a002

The presence of ion-pair intermediates in diacyl peroxide decomposition has been established.Various substituted (4-X-phenyl)phenylacetyl Y-benzoyl peroxides and three corresponding 4-X-benzhydryl-4-nitrobenzoic carbonic anhydrides (X = CH3, H, Cl) were prepared.All compounds decomposed in 90percent acetone-water (v/v), giving the ionic products ester, alkohol, and acid.The fraction of ester (R) was similar to that found in the solvolysis of substituted benzhydryl-N-nitrosoamides, indicating a similar spectrum of ion-pair intermediates.The yield of ester product could be increased markedly by the addition of common ion.The mixed carbonic carboxylic anhydrides were not products of peroxide decomposition in either nucleophilic or nonnucleophilic solvents and showed a lower decompositin rate than the peroxide.Lastly, both the peroxide and the mixed carbonic carboxylic anhydride decomposed in chloroform with net retention.Neither CIDNP nor any radical abstraction product was detected.