Synthesis of trithiadiazepines from tetrasulphur tetranitride and alkynes

Abstract

The reaction of S4N4 with cyano- and trifluoromethyl-substituted alkynes gives trithiadiazepines (1b-d) in good yield; with less reactive alkynes the yields of trithiadiazepines (1) are greatly improved by titanium(IV) chloride catalysis, making a range of functional derivatives of this ring system readily available.