Hypervalent Iodine Mediated Synthesis of Thiosulfonates from Sulfonyl Hydrazides and Their Transformation into Symmetrical Disulfides

Abstract A transition-metal-free synthesis of thiosulfonates has been accomplished by the disproportionate coupling of readily available and inexpensive sulfonyl hydrazides embracing hypervalent iodine(III) [phenyliodine(III) diacetate (PIDA)] as an oxidant. This synthesis involves cleavage of the S–N bond and is endowed with creation of a new S–S bond. The thiosulfonates were further reduced with CS2/KOH to obtain symmetrical disulfides. This protocol features mild reaction conditions in open air, an inexpensive oxidant, and high functional group tolerance with good to excellent product yields.