Synthesis of Cyclic Polysulfides. Reactions of Dithiols and Related Compounds with Elemental Sulfur in Liquid Ammonia

Abstract

Abstract Many cyclic polysulfides, i.e., benzopentathiepins (3a–d), 6H-1,2,3,4,5-benzopentathiocin, 5H-1,2,3,4-benzotetrathiepin, 3H-1,2-benzodithiole, 1,5-dihydro-2,3,4-benzotrithiepin, 1,4-dihydro-2,3-benzodithiin, naphtho[1,8-cd]-1,2-dithiole, 1,2,3-trithiane, 1,2-dithiane, 2,3,4,5-tetrathiabicyclo[4.4.0]decane, and 2,3,4,5,6-pentathiabicyclo[5.4.0]undecane, were synthesized in high yields by new reactions of their corresponding dithiols and related compounds, 1,3-benzodithiole-2-thiones (5) and 1,3-dithiolane-2-thione, with elemental sulfur in liquid ammonia at ambient temperature. In the synthesis of 3a–d from 1,2-benzenedithiol or 5, considerable increase in the product yield was observed upon adding 1,3-dinitrobenzene to the solvent used in work-up.