1,2,3-Dithiazolyl and 1,2,35-Dithiadiazolyl Radicals as Spin-Bearing ...

mixture was refluxed for 20 h yielding a very dark, opaque mixture which was filtered
hot. The precipitate was washed with 2 × 10 mL portions of distilled acetonitrile and
dried under dynamic vacuum to afford the title compound as a dark green powder
(4.3536 g, 15.428 mmol), 140% yield based on 5-chlorobenzo[c][1,2,5]thiadiazol-4-
amine. The high yield is an inherent result of elemental sulfur generated from the large
excess of sulfur monochloride required for the reaction to proceed. ν max (KBr)/cm −1 :
3040(w), 3005(w), 2950(w), 1553(w), 1518(m), 1482 (s), 1424(m), 1388(w), 1349(s),
1286(w), 1261(w), 1213(m), 1176(w), 11569(w), 1106(m), 1020(m), 934(w), 907(w),
877(m), 861(s), 824(m), 758(m), 720(m), 628(w), 584(w), 505(m), 490(w). MS (EI + ):
m/z 245.9 (parent ion), 178.0 (-SCl).
5-Chloro-1H-[1,2,5]thiadiazolo[3,4-e][1,2,3]benzodithiazolium tetrachlorogallate (V-
4). Solid gallium(III) chloride (4.5377 g, 25.771 mmol) was added to a dark green slurry
of V-3 (8.0707g, 28.600 mmol) in distilled acetonitrile (80 mL) to give a dark,
heterogeneous reaction mixture which was stirred at room temperature for 30 minutes. A
pale greyish precipitate was filtered and discarded. Chlorobenzene (80 mL) was added to
the filtrate which was concentrated to half volume via flash distillation to afford the title
compound as a dark, semi-crystalline solid. The product was filtered and washed with 3
× 10 mL portions of chlorobenzene and dried under dynamic vacuum (7.4878 g, 9.8697
mmol), 58% yield based on chloride salt (V-3). ν max (KBr)/cm −1 : 3079(w), 2968(w),
1578(w), 1551(m), 1515(m), 1479(s), 1443(w, 1423(m), 1381(w), 1348(s), 1328(s),
1262(m), 1222(m), 1153(w), 1104(s), 1080(s), 1024(s), 951(w), 935(w), 868(s), 825(m),
804(m), 756(m), 723(w), 699(w), 688(w), 583(w), 538(w), 520(w), 503(w), 473(w). X-
178