474
A. A. Hassan, A.-F. E. Mourad, K. M. El-Shaieb and A. H. Abou-Zied
Vol. 43
2
,3,7,8-Tetrachlorothianthrene-1,4,6,9-tetrone (13a).
Anal. Calcd. for C16H12Cl N OS: C, 47.96; H, 3.02; Cl,
3 3
2
1
6.54; N, 10.49; S, 8.00. Found C, 48.12; H, 2.96; Cl, 26.39; N,
0.66; S, 7.86.
This compound had mp 342-344°, blue crystals from DMF,
-1 13
yield 170 mg (41 %); ir: 1695 (C=O) cm ; C nmr : δ 143.5 (C-
2
%
(
,3,7,8), 149.3 (C-4a,5a,9a,10a), 171.4 (C-1,4,6,9); EI-MS m/z:
N-Allyl-5,6,8-trichloro-7-oxo-2,3-dihydroquinoxaline-1(7H)-
carbothioamide (14c).
+
416/412 (M , 100), 398 (39), 379 (12), 349 (16), 321 (19), 115
55), 87 (91), 64 (36), 36 (69).
This compound had mp 167-169°, pale brown crystals from
ethanol, yield 154 mg (44 %); ir: 3330 (NH), 2970, 2890 (Ali-CH),
Anal. Calcd. for C Cl O S : C, 34.81; Cl, 34.25; S, 15.49.
1
2
4 4 2
Found C, 34.66; Cl, 34.41; S, 15.63.
-1 1
1
685 (C=O) cm ; H nmr: δ 3.48-3.57 (m, 2H, quinoxaline-3-H ),
2
2
,3,7,8-Tetrabromothianthrene-1,4,6,9-tetrone (13b).
3.68-3.86 (m, 2H, quinoxaline-2-H2), 4.22 (m, 2H, allyl-CH2N),
.17-5.20 (m, 2H, allyl-CH =), 5.84-5.92 (m, 1H, allyl-CH=), 7.54
5
2
This compound had mp >360°, blue crystals from DMF, yield
13
(
br, s, 1H, allyl-NH); C nmr: δ 43.6 (allyl-CH N), 48.6, 55.1
2
-
1 13
2
2
%
60 mg (44 %); ir: 1700 (C=O) cm . C nmr: δ 138.2 (C-
(quinoxaline-C-3,2), 115.0 (allyl-CH =), 119.9 (C-8), 134.8 (allyl-
2
,3,7,8), 149.1 (C-4a,5a,9a,10a), 170.9 (C-1,4,6,9); EI-MS m/z:
CH=), 138.6, 141.1 (C-5,6), 151.1 (C-4b), 158.6 (C-4a), 170.1 (C-
+
594/590 (M , 100), 512 (20), 496 (26), 416 (18), 260 (66), 188
+
7), 180.7 (C=S); EI-MS m/z: % 351/347 (M , 32), 313 (18), 277
(
56), 142 (33), 116 (83), 60 (54).
Anal. Calcd. for C Br O S : C, 24.35; Br, 54.00; S, 10.84;
(6), 241 (11), 185 (24), 99 (76), 41 (100), 36 (54).
1
2
4 4 2
Anal. Calcd. for C12H10Cl N OS: C, 41.10; H, 2.87; Cl,
3
3
Found C, 24.51; Br, 53.86; S, 11.02.
3
1
0.33; N, 11.98; S, 9.14. Found C, 41.26; H, 2.69; Cl, 30.13; N,
2.11; S, 9.26.
Reactions of 9a-c with Chloranil (10a) and Bromanil (10b).
5
,6,8-Tribromo-7-oxo-N-phenyl-2,3-dihydroquinoxaline-1(7H)-
A solution of 9a-c (2.0 mmol) in anhydrous THF (15 mL) was
added dropwise with stirring to a solution of 10a,b (1.0 mmol) in
anhydrous THF (20 mL). The mixture was heated under reflux for
carbothioamide (15a).
This compound had mp 273-275°, reddish-brown crystals from
5
hours, during which it turned from yellow into reddish orange.
ethanol, yield 239 mg (46 %); ir: 3310 (NH), 2960 (Ali-CH), 1680
The mixture was concentrated under vacuum and the residue sepa-
rated by plc using cyclohexane/ethyl acetate (3:1) as developing
solvent to give numerous coloured zones, three of which (with the
highest intensity) were extracted and removed. The fastest migrat-
ing one, which quenched all indicator fluorescence upon exposure
to 254 nm UV-light, contained the thiadiazepanes 16a-c, the sec-
ond zone (which was always characterized by an orange colour)
contained the quinoxalines 14a-c and 15a-c, while the third zone
-1 1
(
C=O), 1600 (Ar-C=C) cm ; H nmr: δ 3.44-3.61 (m, 2H, quinox-
aline-3-H ), 3.66-3.85 (m, 2H, quinoxaline-2-H ), 7.10-7.35 (m,
2
2
13
5
H, Ph), 9.65 (br, s, 1H, NHPh); C nmr: δ 48.8, 55.1 (quinoxa-
line-C-3,2), 103.3 (C-8), 124.3, 125.2, 128.8 (Ph-CH), 139.4 (q-C),
1
1
4
27.7, 130.2 (C-5,6), 150.7 (C-4b), 158.4 (C-4a), 170.1 (C-7),
+
80.4 (C=S); EI-MS m/z: % 519/515 (M , 18), 489 (12), 461 (14),
37 (21), 357 (18), 277 (12), 142 (38), 91 (67), 77 (83), 65 (100).
Anal. Calcd. For C H Br N OS: C, 34.64; H, 1.94; Br,
1
5
10
3 3
contained the dihydrobenzoquinones 10a-H and 10b-H .
2
2
46.10; N, 8.08; S, 6.17. Found C, 34.51; H, 2.12; Br, 45.93; N,
.96; S, 6.29.
7
5
,6,8-Trichloro-7-oxo-N-phenyl-2,3-dihydroquinoxaline-1(7H)-
carbothioamide (14a).
N-Benzyl-5,6,8-tribromo-7-oxo-2,3-dihydroquinoxaline-1(7H)-
carbothioamide (15b).
This compound had mp 254-256°, brown crystals from ethanol,
yield 189 mg (49 %); ir: 3325 (NH), 2965 (Ali-CH), 1685 (C=O),
This compound had mp 282-284°, reddish-brown crystals from
acetonitrile, yield 219 mg (41 %); ir: 3330 (NH), 2965, 2840 (Ali-
-
1 1
1
590 (Ar-C=C) cm ; H nmr: δ 3.46-3.60 (m, 2H, quinoxaline-3-
2
H ), 3.64-3.87 (m, 2H, quinoxaline-2-H ), 7.08-7.37 (m, 5H, Ph),
-1 1
2
CH), 1690 (C=O), 1590 (Ar-C=C) cm ; H nmr: δ 3.53-3.64 (m,
1
3
9
1
1
.69 (br, s, 1H, NHPh); C nmr: δ 48.8, 55.3 (quinoxaline-C-3,2),
2
4
H, quinoxaline-3-H ), 3.68-3.83 (m, 2H, quinoxaline-2-H ),
2
2
20.1 (C-8), 124.8, 125.3, 128.9 (Ph-CH), 139.4 (q-C), 138.5,
.64 (br, s, 2H, CH Ph), 6.98-7.28 (m, 5H, Ph), 9.45 (br, s, 1H,
2
41.3 (C-5,6), 151.1 (C-4b), 158.4 (C-4a), 170.2 (C-7), 180.3
+
NHCH Ph); EI-MS m/z: % 533/529 (M , 18), 503 (11), 474 (6),
2
+
(
(
C=S); EI-MS m/z: % 387/383 (M , 36), 349 (11), 277 (8), 221
21), 205 (9), 135 (57), 91 (100), 77 (81), 65 (64).
451 (27), 371 (18), 291 (16), 142 (36), 91 (100), 77 (67), 65 (43).
Anal. Calcd. for C16H12Br N OS: C, 35.98; H, 2.26; Br,
3
3
Anal. Calcd. for C H Cl N OS: C, 46.59; H, 2.61; Cl,
1
5
10
3
3
44.88; N, 7.87; S, 6.00. Found C, 36.14; H, 2.18; Br, 45.08; N,
7.96; S, 5.87.
2
7.51; N, 10.87; S, 8.29. Found C, 46.68; H, 2.53; Cl, 27.38; N,
1
1.03; S, 8.44.
N-Allyl-5,6,8-tribromo-7-oxo-2,3-dihydroquinoxaline-1(7H)-
carbothioamide (15c).
N-Benzyl-5,6,8-trichloro-7-oxo-2,3-dihydroquinoxaline-1(7H)-
carbothioamide (14b).
This compound had mp 185-187°, reddish brown crystals from
ethanol, yield 208 mg (43 %); ir: 3310 (NH), 2970, 2890 (Ali-
This compound had mp 269-271°, brown crystals from ace-
tonitrile, yield 188 mg (47 %); ir: 3320 (NH), 2960, 2870 (Ali-
CH), 1690 (C=O), 1600 (Ar-C=C) cm ; H-nmr: δ 3.50-3.61 (m,
2
4
-1 1
CH), 1685 (C=O) cm ; H nmr: δ 3.46-3.58 (m, 2H, quinoxa-
-1 1
line-3-H ), 3.62-3.78 (m, 2H, quinoxaline-2-H ), 4.18 (m, 2H,
2
2
H, quinoxaline-3-H ), 3.70-3.85 (m, 2H, quinoxaline-2-H ),
allyl-CH N), 5.18-5.22 (m, 2H, allyl-CH =), 5.92-6.03 (m, 1H,
2
2
2
2
.60 (br, s, 2H, CH Ph) 7.0-7.29 (m, 5H, Ph), 9.42 (br, s, 1H,
allyl-CH=), 7.58 (br, s, 1H, allyl-NH); EI-MS m/z: % 483/479
2
1
3
+
NHCH Ph); C nmr: δ 48.7, 55.2 (quinoxaline-C-3,2), 50.2
(M , 21), 401 (16), 321 (11), 241 (6), 213 (17), 185 (32), 86 (53),
2
(
CH Ph), 119.8 (C-8), 126.5, 127.1, 129.0 (Ph-CH), 140.1 (q-C),
41 (100).
2
1
1
38.4, 141.2 (C-5,6), 150.8 (C-4b), 158.8 (C-4a), 170.0 (C-7),
81.1 (C=S); EI-MS m/z: % 400/397 (M , 22), 363 (17), 263
Anal. Calcd. for C12H10Br N OS: C, 29.78; H, 2.08; Br,
49.53; N, 8.68; S, 6.63. Found C, 29.64; H, 1.96; Br, 49.68; N,
8.52; S, 6.47.
3 3
+
(
27), 235 (11), 149 (42), 91 (62), 77 (100), 65 (83).