New reaction of dithiophosphoric acids with O-thioacylhydroxylamines. Nucleophilic substitution or single electron transfer process?

Abstract

Disubstituted or sterically hindered hydroxylamines react with bulky S-thioacyl dithiophosphates yielding O-thioacylhydroxylamines. The reaction of O-thioacylhydroxylamines with dithiophosphoric acids yields acyl thiophosphoryl disulfides and ammonium dithiophosphates. The influence of radical traps on the reaction yield strongly suggests that radicals are involved in the mechanism of the process. The low redox potential of dithiophosphates, the observed photochemical stability of O-thioacylhydroxylamines and the influence of light on acyl thiophosphoryl disulfides yield imply involvement of a single electron transfer process in the investigated reaction.