We have recently introduced the use of ammonium peroxydisulfate to effect the oxidation of diphenyl diselenide and to produce phenylselenenyl sulfate. Since the sulfate is a resonance-stabilized anion and a very poor nucleophile this reagent behaves as a very efficient electrophilic phenylselenenylating agent. lI2 Ammonium peroxydisulfate also reacts with phenyl alkyl selenides to effect deselenenylation reactions from which ...