A. S. A. Youssef, F. A. El-Mariah, F. T. Abd-Elmottaleb, and H. E. Hashem
Vol 000
104, 103, 98, 89, 77 (Ph). Anal. Calcd for C16H13N3O: C, 72.99;
H, 4.98; N, 15.96. Found: C, 73.11; H, 5.07; N, 16.04.
3 (10 mmol) in acetic acid/water (1:1 by volume) (20 mL).
Stirring was then continued at room temperature for 3 h. The
solid obtained was filtered off, washed with water, and finally
recrystallized from the suitable solvent to give: (E/Z)-N-3-(2-
carbamothioylhydrazinyl)-3-oxo-1-phenylprop-1-en-2-yl) benzamide
(E/Z)-14: This compound was obtained as pale brown crystals
(ethanol), (36%), mp 178–180°C; IR: 3400–3129 br NH, 3059,
3027 aryl-H, 1647 C═O, 1578, 1513 C═C, 1282 C═S, 754,
2-Benzoyl-5-benzylidene-3-phenyl-1,2-dihydro-1,2,4-triazin-6(5H)-
one 10: This compound was obtained as brown crystals (dil. etha-
nol), (80%), mp 149–150°C; IR: 3412 NH, 3057, 3026 aryl-H,
1694, 1629 C═O, 1601 C═N, 1493, 1447 C═C, 763, 698 cmÀ1
;
ms: m/z 368 (M++1), 367 (M+), 366, 334, 315, 306, 291, 272,
252, 218, 122, 105 (PhCO), 77 (Ph). Anal. Calcd for
C23H17N3O2: C, 75.19; H, 4.66; N, 11.44. Found: C, 75.11; H,
5.07; N, 11.04.
693 cmÀ1
; δ 4.12 (br s, 2H, NH2
1H-NMR (DMSO-d6):
exchangeable), 4.35 (br s, 1H, SH exchangeable), 6.84 (br s,1H, ═C
(SH)NH exchangeable), 7.16 (s, 1H, ═CH), 7.33–8.43 (m,
41H, ArH + ═CH), 9.96 (br s, 1H, ═C(SH)NH exchangeable),
10.13 (br s, 1H, NHC═S exchangeable), for E isomer: 10.26 (br s,
1H, NHCO exchangeable), 11.10 (br s, 1H, NHCOPh
Ring closure of dibenzoylhydrazide (E)-7 with phosphorus
oxychloride.
Phosphorus oxychloride (4.5 mL) was added
dropwise to (0.38 g) of the dibenzoylhydrazide (E)-7. The
reaction mixture was refluxed for 20 min., left to cool, and
poured onto crushed ice. The solid precipitated was filtered off,
washed with water, and recrystallized to give (Z)-N-
(4-benzylidene-5-oxo-2-phenyl-4, 5-dihydro-1H-imidazol-1-yl) benzamide
(Z)-9: This compound was obtained as orange crystals (dil.
ethanol), (92%), mp 256–258°C; IR: 3203 NH, 3060, 3029 aryl-
H, 1712 C═O imidazolone, 1638 C═O amide, 1602 C═N,
exchangeable). For
Z isomer: 10.39 (br s, 1H, NHCO
exchangeable), 11.71 (br s, 1H, NHCOPh exchangeable); ms: m/z
341 (M+ + 1), 340 (M+), 324 (M+ À NH2), 281 (M+ À HNCS),
264 (M+ À (NH2)2CS), 263 (M+ À ((NH2)2CS + H)), 250
(M+ À NH2CSNHNH), 120 (PhCONH), 119 (PhCNO), 105
(PhCO), 77 (Ph). Anal. Calcd for C17H16N4O2S: C, 59.98; H,
4.74; N, 16.46. Found: C, 60.08; H, 4.99; N, 16.34.
1
1556, 1524 C═C, 766, 690 cmÀ1; H-NMR (DMSO-d6): δ 7.34
(Z)-2-(2-Benzamido-3-phenylacryloyl) hydrazine carboxamide
(Z)-15. This compound was obtained as pale green crystals
(ethanol), (63%), mp 218–220°C; IR: 3416, 3209 NH, 3051 aryl-H,
(s, 1H, ═CH), 7.45–8.39 (m, 15H, ArH), 11.69 (br s, 1H, NH
exchangeable); ms: m/z 367 (M+), 364, 117, 105 (PhCO), 104,
103, 102, 77 (Ph). Anal. Calcd for C23H17N3O2: C, 75.19; H,
4.66; N, 11.44. Found: C, 75.61; H, 4.87; N, 11.84.
1659, 1635 C═O, 1580, 1522 C═C, 754, 692 cmÀ1 1H-NMR
;
(DMSO-d6): δ 6.02 (br s, 2H, NH2 exchangeable), 7.10 (s, 1H, ═CH),
7.23–7.36 (m, 8H, ArH, J=6.9, 7.2, 7.5Hz), 7.85 (br s, 1H,
NHCONH2 exchangeable), 8.05 (d, 2H, ArH, J = 6.9 Hz),
10.02 (br s, 1H, NHNHCO exchangeable), 10.22 (br s, 1H,
NHCOPh exchangeable); ms: m/z 308 (M+ À NH2), 250
(M+ À NH2CONHNH), 145 (M+ À (H2NCONHNH + PhCO)),
117, 105 (PhCO), 77 (Ph). Anal. Calcd for C17H16N4O3: C,
62.95; H, 4.97; N, 17.27. Found: C, 63.08; H, 4.99; N, 17.34.
The same thiosemicarbazide derivative (E/Z)-14 was also
obtained from heating of an alcoholic solution of oxazolone 1
with thiosemicarbazide in the presence of a catalytic amount of
triethyl amine. The product obtained was identical in all respects
(mp, mmp, and TLC), with that obtained from the reaction
between the hydrazide (Z)-3 and potassium thiocyanate.
Reaction of hydrazide (Z)-3 with carbon disulphide
General procedure in ethanolic sodium hydroxide.
To a
solution of hydrazide (Z)-3 (7.1 mol) in 10% ethanolic sodium
hydroxide (3 g NaOH in 30 mL ethanol), carbon disulphide
(10 mL) was added. The reaction mixture was heated under
reflux for 3 h. The reaction mixture was poured onto ice cold
HCl. The solid obtained was filtered off, washed with water,
dried, and recrystallized to afford 5-(1-amino-2-phenylvinyl)-1,
3, 4-oxadiazol-2(3H)-thione 11: This compound was obtained
as yellow crystals (ethanol), (74%), mp 232–234°C; IR: 3288,
3246, 3180 NH, NH2, 3057 aryl-H, 1655, 1638 C═N, 1612
1
C═C, 1259 C═S, 765, 687 cmÀ1; H-NMR (DMSO-d6): δ 6.64
(s, 1H, ═CH), 7.37–7.98 (m, 7H, 5ArH + NH2, J = 7.5, 7.8 Hz),
12.17 (br s, 1H, NHC═S exchangeable); ms: m/z 221 (M+ + 2),
220 (M+ + 1), 219 (M+), 218, 204, 203, 149, 144, 134, 118, 117,
116, 105, 104, 102, 96, 90, 89. Anal. Calcd for C10H9N3OS: C,
54.78; H, 4.14; N, 19.16. Found: C, 54.28; H, 4.27; N, 19.44.
Ring closure of hydrazide (Z)-3 using 10% aqueous sodium
hydroxide. A solution of hydrazide (Z)-3 (3.5 mmol) in 10%
sodium hydroxide (10mL) was heated under reflux for 1 h., left to
cool to room temperature and poured onto ice cold HCl. The solid
product was filtered off, dried, and recrystallized to give 5-
benzyl-3-phenyl-1, 2, 4-triazin-6(1H)-one 6: This compound
was obtained as white needles (ethanol), (96%), mp 206–208°
C; IR: 3309, 3200, 3128 NH, 3064, 3026 aryl-H, 2954, 2894
alkyl-H, 1656 C═O, 1591 C═N, 1567, 1540 C═C, 747,
In ethanol and conc. H2SO4. A mixture of hydrazide (Z)-3
(0.01 mol) in ethanol (25 mL), carbon disulphide (5 mL), and few
drops of concentrated sulfuric acid was heated on a water bath for
3 h. The solid obtained after cooling was filtered, washed with wa-
ter, dried, and then recrystallized to afford O-ethyl-5-benzylidene-
6-oxo-3-phenyl-5,6-dihydro-1,2,4-triazin-2(1H)carbothioate 12:
This compound was obtained as pale yellow crystals (DMF),
(45%), mp >300°C; IR: 3200, 3143 NH, 3063, 3031 aryl-H,
2957, 2843 alkyl-H, 1661 C═O, 1590, 1566, 1523 C═N or
C═C, 1142 C═S,793, 696cmÀ1; 1H-NMR (DMSO-d6): δ 1.07 (t,
3H, CH3, J = 6.6 Hz), 3.45 (q, 2H, CH2O), 6.94 (s, 1H, ═CH),
7.11–8.14 (m, 10H, ArH), 13.5 (br s, 1H, NH exchangeable); ms:
m/z 351 (M+), 263 (M+ À C2H5OC═S), 119, 118, 105, 104, 103,
91, 80, 79, 77(Ph). Anal. Calcd for C19H17N3O2S: C, 64.94; H,
4.88; N, 11.96. Found: C, 65.08; H, 4.99; N, 12.14.
; δ 4.16 (s, 2H,
696 cmÀ1 1H-NMR (DMSO-d6): For 6:
CH2Ph), 7.23–8.01 (m, 10H, ArH, J = 7.5, 7.8 Hz), 13.53 (br s,
1H, NHa exchangeable); For (E)-6a: δ 6.36 (s, 1H, ═CH),
7.23–8.01 (m, 10H, ArH, J = 7.5, 7.8 Hz), 11.29 (br s, 1H,
NHc exchangeable), 13.53 (br s, 1H, NHa exchangeable); For
(E)-6b: δ 6.36 (s, 1H, ═CH), 7.23–8.01 (m, 10H, ArH, J = 7.5,
7.8 Hz), 9.85 (br s, 1H, NHb exchangeable), 13.53 (br s, 1H,
NHa exchangeable); ms: m/z 263 (M+), 262, 118, 117, 104,
103, 91, 89, 77 (Ph). Anal. Calcd for C16H13N3O: C, 72.99;
H, 4.98; N, 15.96. Found: C, 72.71; H, 4.67; N, 15.84.
Reaction of the hydrazide (Z)-3 with potassium thiocyanate
or potassium cyanate. A solution of potassium thiocyanate or
potassium cyanate (10 mmol) in water (10 mL) was added
dropwise with stirring at 0°C to a solution of the hydrazide (Z)-
Action of aqueous sodium hydroxide on 2-benzoyl-1, 2,
4-triazinone 10, thiosemicarbazide derivative (E/Z)-14 and
semicarbazide derivative (Z)-15. A solution of 2N NaOH
(40 mL) was added to the triazinone 10 or thiosemicarbazide
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet