A simple and rapid method for efficient synthesis of sulfonyl chlorides/bromides from sulfonyl hydrazide with NXS (X = Cl or Br) and late-stage conversion to several other functional groups was described. A variety of nucleophiles could be engaged in this transformation, thus permitting the synthesis of complex sulfonamides and sulfonates. In most cases, these reactions are highly selective, simple, and clean, affording products at excellent yields.

A cobalt-catalyzed three-component reaction of carboxylic acids, diazo reagents andtert-butyl hydroperoxide was realized, which afforded a straightforward synthesis of α-acyloxy esters in good yields.