D. Maitraie et al. / Journal of Fluorine Chemistry 118 (2002) 73–79
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4.10. Reaction of compounds 4a and 4b with aldehydes
MS (m/z): 349 (Mþ), 331, 305, 272, 256, 104, 77. Analysis.
Calcd. for C17H14F3N3O2: C, 58.45%; H, 4.03%; N, 12.02%.
Found: C, 58.52%; H, 4.32%; N, 12.13%.
The compounds 4a and 4b (2 mmol) and aldehydes
(2 mmol) were taken in acetic acid (5 ml). The homogenous
reaction mixture was stirred at room temperature and the
progress of the reaction was monitored by TLC for 4 h. The
reaction mixture was cooled and poured into crushed ice.
The separated solid was filtered, washed with water till
washings are neutral to litmus and dried. The dried product
was found to contain two regioisomers 5 and 6. Each isomer
was separated by passing through column of silicagel in
n-hexane/ethyl acetate in 3:1 ratio.
4.15. 1,2-Dihydro-2-methyl-5-trifluoromethyl-7-phenyl-8-
carboxamido-4(3H)-quinazolinone (5c)
IR (KBr) n: 3440, 3350, 3100, 1652, 1162 cmꢀ1. 1H NMR
(200 MHz, DMSO-d6) d: 1.48 (d, 3H, CH3 J ¼ 16 Hz); 4.8
(m, 1H, methine H); 6.19 (s, 1H, NH); 6.98 (s, 1H, H-C (6));
7.09 (s, 1H, CONH2); 7.19 (s, 1H, CONH2); 7.42 (s, 5H,
aromatic H); 8.15 (s, 1H, CONH). MS (m/z): 349 (Mþ) 333,
316. Analysis. Calcd. for C17H14F3N3O2: C, 58.45%; H,
4.03%; N, 12.02%. Found: C, 58.50%; H, 4.15%; N,
12.14%.
4.11. 1,2-Dihydro-2,7-dimethyl-5-trifluoromethyl-8-
carboxamido-4(3H)-quinazolinone (5a)
IR (KBR) n: 3340, 3220, 2368, 1665, 1174, 616 cmꢀ1. 1H
NMR(200 MHz, DMSO-d6)d:1.45(d,3H, CH3,J ¼ 20 Hz);
2.69 (s, 3H, CH3); 4.81 (m, 1H, methine H); 5.58 (s, 1H, NH);
6.81 (s, 1H, H-C (6)); 7.39 (s, 1H, CONH2); 7.40 (s, 1H,
CONH2); 7.91 (s, 1H, CONH). MS (m/z): 287, 269. Analysis.
Calcd. for C12H12F3N3O2: C, 58.29%; H, 4.89%; N, 15.37%.
Found: C, 58.25%; H, 4.95%; N, 15.92%.
4.16. 1,2-Dihydro-2-methyl-5-phenyl-7-trifluoromethyl-8-
carboxamido-4(3H)-quinazolinone (6c)
IR (KBr) n: 3350, 3290, 3090, 1690, 1120 cmꢀ1. 1H NMR
(200 MHz, DMSO-d6) d: 1.45 (d, 3H, CH3, J ¼ 18 Hz);
4.85 (m, 1H, methine H); 5.80 (s, 1H, NH); 6.83 (s, 1H, H-C
(6),); 7.29 (s, 5H, aromatic H); 7.42 (s, 1H, CONH2); 7.61 (s,
1H, CONH2); 7.95 (s, 1H, CONH). MS (m/z): 349 (Mþ),
334, 317, 158, 69. Analysis. Calcd. for C17H14F3N3O2: C,
58.45%; H, 4.03%; N, 12.02%. Found: C, 58.51%; H,
4.22%; N, 12.08%.
4.12. 1,2-Dihydro-2,5-dimethyl-7-trifluoromethyl-8-
carboxamido-4(3H)-quinazolinone (6a)
IR (KBr) n: 3314, 3225, 2365, 1665, 1524, 1172,
1137 cmꢀ1
.
1H NMR (200 Hz, DMSO -d6) d: 1.50 (d,
4.17. 1,2-Dihydro-2,7-diphenyl-5-trifluoromethyl-8-
carboxamido-4(3H)-quinazolinone (5d)
3H, CH3, J ¼ 16 Hz); 2.65 (s, CH3, 3H); 4.80 (m, 1H,
methine H); 5.5 (s, 1H, NH); 6.8 (s, 1H, H-C (6)); 7.35
(s, 1H, CONH2); 7.37 (s, 1H, CONH2); 7.82 (s, 1H, CONH).
MS (m/z): 287 (Mþ), 269, 272, 255, 154. Analysis. Calcd. for
C12H12F3N3O2: C, 58.29%; H, 4.89%; N, 15.37%. Found: C,
58.35%; H, 4.92%; N, 15.51%.
IR (KBr) n: 3468, 3186, 1688, 1513, 1288, 1175 cmꢀ1. 1H
NMR (200 MHz, DMSO-d6) d: 5.5 (s, 1H, methine H); 6.38
(s, 1H, NH); 6.42 (s, 1H, CONH2); 6.58 (s, 1H, CONH2);
6.92 (s, 1H, H-C (6)); 7.15 (s, 5H, aromatic H); 7.8 (s, 1H,
CONH). MS (m/z): 412 (Mþ), 393, 375, 317, 185, 93.
Analysis. Calcd. for C22H16F3N3O2: C, 64.23%; H,
3.92%; N, 10.21%. Found: C, 64.28%; H, 3.98%; N,
10.29%.
4.13. 1,2-Dihydro-2-phenyl-5-trifluoromethyl-7-methyl-8-
carboxamido-4(3H)-quinazolinone (5b)
IR (KBr) n: 3510, 3450, 3160, 1690, 1120 cmꢀ1. 1H NMR
(200 MHz, DMSO-d6) d: 2.69 (s, 3H, CH3); 5.75 (s, 1H,
methine H); 6.08 (s, 1H, NH); 6.81 (s, 1H, H-C (6)); 7.35 (m,
3H, aromatic H, 1H CONH2); 7.40 (s, 1H, CONH2); 7.55 (m,
2H, aromatic H); 8.09 (s, 1H, CONH). MS (m/z): 349 (Mþ),
331, 272, 255, 77. Analysis. Calcd. for C17H14F3N3O2: C,
58.45%; H, 4.03%; N, 12.02%. Found: C, 58.52%; H,
4.32%; N, 12.13%.
4.18. 1,2-Dihydro-2,5-diphenyl-7-trifluoromethyl-8-
carboxamido-4(3H)-quinazolinone (6d)
IR (KBr) n: 3437, 3296, 3175, 1670, 1456, 1118 cmꢀ1
.
1H NMR (200 MHz, DMSO-d6) d: 5.82 (s, 1H, methine H);
6.50 (s, 1H, NH); 6.92 (s, 1H, H-C (6)); 7.3 (s, 5H, aromatic
H); 7.38 (m, 3H, aromatic H); 7.42 (s, 1H, CONH2); 7.58 (s,
1H, CONH2); 7.63 (m, 2H, aromatic H); 8.23 (s, 1H,
CONH). MS (m/z): 411 (Mþ) 393, 307, 185, 93. Analysis.
Calcd. for C22H16F3N3O2: C, 64.23%; H, 3.92%; N, 10.21%.
Found: C, 64.28%; H, 3.98%; N, 10.3%.
4.14. 1,2-Dihydro-2-phenyl-5-methyl-7-trifluoromethyl-8-
carboxamido-4(3H)-quinazolinone (6b)
IR (KBr) n: 3439, 3294, 3184, 2925, 1668, 1132 cmꢀ1. 1H
NMR (200 MHz, DMSO-d6) d: 2.39 (s, 3H, CH3); 5.69
(s, 1H, methine H); 6.52 (s, 1H, NH); 6.93 (s, 1H, H-C (6));
7.39 (m, 3H, aromatic H); 7.54 (m, 2H, aromatic H); 7.79
(s, 1H, CONH2); 7.87 (s, 1H CONH2); 8.30 (s, 1H, CONH).
4.19. Dehydrogenation of quinazolinones (5 and 6)
The compound 5 or 6 (0.16 mmol) was dissolved in dry
dichloromethane (10 ml), active MnO2 (650 mg) was added