Cross-Dehydrogenative Coupling of Azoarenes with Dialkyl Disulfides.

A catalyst-free cross-dehydrogenative coupling reaction of purines and some azoarenes with dialkyl disulfides has been developed. This procedure provided a novel strategy to construct unsymmetrical disulfides through the α-heterocyclic functionalization of symmetrical dialkyl disulfides. The S-S bond was successfully tolerated in this transformation. The mild conditions and the broad scope of azoarenes indicated the potential application of this procedure.