Unexpected reaction of 2-(bromomethyl)-1,3-thiaselenole with ammonium thiocyanate.

The article discusses a procedure of 2-(bromomethyl)-1,3-thiaselenole preparation by a new reaction of selenium dibromide with divinyl sulfide. It notes that the reactions occur through the formation of six-membered rings, 2,6-dihalo-1,4-thiaselenanes that underwent a rearrangement into five-membered rings, 5-halo-2-(halomethyl)-1,3- thiaselenoles, with dehydrochlorination and the formation of an endocyclic double bond resulting in 2-(halomethyl)-1,3-thiaselenoles.