Conformational isomers of 1,2,5,6-tetrathiocins and the photoisomerization of a 1,2,5,6-tetrathiocin into a 1,2,3,6-tetrathiocin: X-ray structures of (C6X4S2)2 (X = F, Cl) and C6F4SSSC6F4S

The 1,2,5,6-tetrathiocins (C 6 X 4 S 2 ) 2 (3a, X = F; 3b, X = Cl) are obtained in high yields by the oxidation of the dithiols 1,2-C 6 X 4 (SH) 2 (X = F, Cl) with I 2 or SO 2 Cl 2 , respectively. In the solid state 3a has the C 2h (chair) conformation and crystallizes in two different phases: alpha-(C 6 F 4 S 2 ) 2 , monoclinic, P2 1 /a, a = 9.351(2), b = 6.465(2), and c = 11.546(2) Å, ß = 95.60(1)°, V = 694.6(2) Å 3 , Z = 2; and ß-(C 6 F 4 S …