Reactions of 1,2-dihaloethanes with chalcogenide anions

Reactions of 1,2-dihaloethanes with chalcogenide anions generated from elemental chalcogens and dimethylchalcogens were performed in the hydrazine hydrate-KOH system. The use of anions Se x 2− and Te x 2− (x = 1−4) resulted in ethylene evolution and chalcogen regeneration (or in increased x value in an anion). Oligomers of Thiokol type formed only in the reaction of the 1,2-dichloroethane with a mixture of potassium disulfide and diselenide. The reductive cleavage of oligomers obtained in the hydrazine hydrate-KOH system followed by methylation led to the formation of 1,2-bis(methylthio)ethane, 1-methylseleno-2-methylthioethane, and 1,2-bis(methylseleno)ethane. The features of substitution with chalcogenide anions in vicinal dihalides are discussed. Mass spectra of compounds obtained were measured and analyzed.