Acid- and Base-Dependent Hydrolysis of N-(Sulfonatooxy)-3-bromoacetanilide: Involvement of N-(3-Bromophenyl)hydroxylamine-O-sulfonate

Article abstract of DOI:10.1021/jo00386a019

N-(Sulfonatooxy)-3-bromoacetanilide (1e) undergoes hydrolysis at 80 deg C in the range pH 1.0-8.0 by acid- and base-dependent processes and by an uncatalyzed path.The uncatalyzed reaction exhibits the same characteristics as the uncatalyzed N-O bond-cleavage reactions of the more reactive N-(sulfonatooxy)acetanilides.The pH-dependent pathways involve the hydrolysis of 1e to form N-(3-bromophenyl)hydroxylamine-O-sulfonate (2).This material cannot be directly detected under the conditions of this study, but its existence can be inferred from product study and trapping data.Although 2 undergoes decomposition entirely by heterolytic N-O bond cleavage to yield nitrenium ion intermediate 14, a less reactive analogue of 2, N-(3-bromophenyl)-O-pivaloylhydroxylamine (4), apparently undergoes competitive homolytic and heterolytic N-O bond cleavage to yield both the arylamino radical 17 and the nitrenium ion 14.Both 2 and 4 serve as models for certain suspected carcinogenic metabolites of polycyclic aromatic amines and amides.