SYNTHESIS AND STRUCTURE OF 3,7-DIPHENYL-3H,7H-1,5,2,4,6,8,3,7-DITHIA(1,5-SIV)TETRAZADIARSOCINE AND 3,7-DIMESITYL-3H,7H-1,5,2,4,6,8,3,7-DITHIA(1,5-SIV)TETRAZADIARSOCINE, AS2S2N4C12H10 AND AS2S2N4C18H22

The crystal data for the title compounds are as follows. As2S2N4C18H22: triclinic, P1, at -100 °C; a = 7.390 (2), b = 8.089 (2), c = 18.235 (5) Å α = 86.63 (2), β = 106.16 (2), γ = 98.89 (2)°; V= 1034.1 (5) Å3; Z = 2; Dc= 1.63 gcm-3; µ(MO Ka) 36.15 cm-1; R = 6.3% for 2764 reflections. As2S2N4C12H10: orthorhombic, Pnma, at -100 °C; a = 21.288 (4), b = 28.581 (6), C = 7.532 (1) Å V = 4582.8 (4) Å3; Z = 12; Dc= 1.84 g cm-3; µ(MO Ka) 48.68 cm-1; R = 5.7% for 2718 reflections. In each material, the AS2S2N4group exists as a boat-shaped ring with arsenic atoms at prow and helm, joined by two -N-S-N chains. The four nitrogen atoms are coplanar. Each arsenic is also bonded to a phenyl or mesityl group. While the ring is conformationally similar to the S4N4cage, cross-ring As-As or S-S interactions may be considered minimal. Attempts to prepare polymers analogous to (SN)x, either by thermal splitting of the title compounds or by reaction of arylarsenic dichloride with sulfur diimides, have been unsuccessful. © 1979, American Chemical Society. All rights reserved.