5,6-Diphenylthieno[2,3-d][1,3]dithiole-2-thione.

The title compound, C(17)H(10)S(4), has two independent molecules in the asymmetric unit. In both molecules, the fused heterocycle is almost planar and the phenyl groups make dihedral angles of 42.88 (9) and 52.79 (8) degrees with the fused heterocycle in one molecule, and angles of 40.62 (9) and 52.28 (8) degrees in the other. The crystal packing is governed by short intermolecular S.S interactions, the shortest contact being 3.333 (1) A.

5,6-Diphenyl[1,3]dithiolo[4,5-b]-dithiine-2-thione.

In the title compound, C(17)H(10)S(5), the dithiine ring adopts a boat conformation while the dithiole ring has an envelope conformation. The phenyl groups are planar and make dihedral angles of 40.7 (2) and 59.8 (2) degrees with the best plane of the thiine ring. The shortest intermolecular S...S contact is 3.305 (2) A.

5-Benzyl-5-phenyl[1,3]dithiolo[4,5-d]-[1,3]dithiole-2-thione.

In the title compound, C(17)H(12)S(5), the dithiole ring bearing the aryl substituents assumes an envelope conformation with the maximum deviation from planarity being -0.053 A. The phenyl and benzyl rings are twisted by 33.0 (1) and 31.1 (1) degrees, respectively, out of the dithiole plane. The crystal packing is governed by short S...S interactions, with the shortest being 3.550 (2) A.