Optimum yields of heterocyclic products are obtained when the reaction of 4-XC(6)H(4)CN(2)(SiMe(3))(3) (X = Br, CF3) with PhSCl in a 1:3 molar ratio in CH2Cl2 is carried out at -100 degrees C followed by the mixture being warmed to -70 degrees C for 16 h. Under these conditions the eight-membered rings (4-XC(6)H(4))(2)C(2)N(4)S(2)Ph(2) (1b, X = Br; 1c, X = CF3) are obtained in 64 and 80% yields, respectively, in addition to the purple diazenes Z,E,Z-PhSN(4-XC(6)H(4))CN=NC(C(6)H(4)X-4)NSPh (2b, 8%; 2c, 19%) and, in the case of X = Br, the sixteen-membered ring (4-BrC6H4)(4)C(4)N(8)S(4)Ph(4) (3) (8%). With a reaction time of 40 h the yield of 3 is increased to 25%. By contrast, the reaction of 3-BrC6H4CN2(SiMe(3))(3) With 3 equiv of PhSCl at -70 degrees C gives Z,E,ZPhSN(3-BrC6H4)CN=NC(3-BrC6H4)NSPh in 75% yield. A possible pathway for the formation of cyclic products is proposed. The solid-state structures of Ib, Ic, and 3 were determined by X-ray crystallography. The eight-membered rings 1b and 1c adopt long boat conformations with the phenyl groups (attached to S) in equatorial positions. Density functional theory (DFT) calculations for the model ring system (HC)(2)N-4(SH)(2) reveal that the observed C-2v geometry is the result of a second-order Jahn-Teller distortion of the planar (D-2h) structure. The chair conformer (C-2h) is only ca. 10 kJ mol(-1) higher in energy than the boat conformer. The hypothetical dianion (HC)(2)N-4(SH)(2)(2-) is predicted to have a transannular S ... S contact of about 2.5 Angstrom. The sixteen-membered ring 3 has a cradle-like structure with S-4 symmetry.