Quantum Chemical Study of Mechanisms of Organic Reactions: X. Reaction of Dipotassium Propane-1,3-bis(thiolate) with 1,3-Dichloropropene in the System Hydrazine Hydrate–KOH

A mechanism has been proposed for the reaction of 1,3-dichloropropene with dipotassium propane-1,3-bis(dithiolate) in the system hydrazine hydrate–potassium hydroxide on the basis of DFT quantum chemical calculations at the B3LYP/6-311++G(d,p) level of theory. The first stage of this reaction has been found to be nucleophilic substitution of one chlorine atom of 1,3-dichloropropene linked to the sp3-carbon atom by the sulfur atom of propane-1,3-bis(thiolate) to give the corresponding monosubstitution product. Further transformations of the latter could lead to the formation of six-, seven-, and eight-membered sulfur heterocycles, as well as of a linear structure as a result of reaction of the monosubstitution product with the second 1,3-dichloropropene molecule.