32
M. Adib et al. / Tetrahedron Letters 51 (2010) 30–32
Mahdavi, M.; Mahmoodi, N.; Pirelahi, H.; Bijanzadeh, H. R. Synlett 2006, 1765–
J = 7.4 Hz, 2CH), 7.38 (2H, d, J = 7.5 Hz, 2CH), 7.44 (1H, t, J = 7.5 Hz, CH), 7.59
(1H, d, J = 8.1 Hz, CH), 7.74 (1H, t, J = 7.5 Hz, CH), 8.07 (1H, d, J = 7.8 Hz, CH),
12.39 (1H, br s, NH). 13C NMR (125.8 MHz, CDCl3): d 40.73 (CH2), 120.71 (C),
125.63, 126.08, 126.70, 126.86, 128.40, 128.80, and 134.26 (9CH), 136.50,
148.87, and 155.88 (3C), 161.80 (C@O). 2-Phenethyl-4(3H)-quinazolinone (4q)
colorless crystals, mp 208 °C, yield: 0.46 g, 92%. Anal. Calcd for C16H14N2O
(250.30): C, 76.78; H, 5.64; N, 11.19. Found: C, 76.6; H, 5.8; N, 11.0. 1H NMR
(500.1 MHz, CDCl3): d 2.89 (2H, t, J = 7.5 Hz, CH2), 3.04 (2H, t, J = 7.5 Hz, CH2),
7.16–7.20 (1H, m, CH), 7.25–7.29 (4H, m, 4CH), 7.45 (1H, t, J = 7.8 Hz, CH), 7.61
(1H, d, J = 8.1 Hz, CH), 7.77 (1H, dt, J = 1.5, 8.1 Hz, CH), 8.07 (1H, d, J = 7.9 Hz,
CH), 12.23 (1H, br s, NH). 13C NMR (125.8 MHz, CDCl3): d 32.39 and 36.23
(2CH2), 120.79 (C), 125.63, 125.93, 126.00, 126.75, 128.26, 128.28, and 134.21
(9CH), 140.69, 148.83, and 156.53 (3C), 161.72 (C@O).
1767; Adib, M.; Ghanbary, K.; Mostofi, M.; Bijanzadeh, H. R. Tetrahedron 2005,
61, 2645–2648.
21. The procedure for the preparation of 2-(4-methylphenyl)-4(3H)-quinazolinone
4b is described as an example: A mixture of 4-methylbenzonitrile (0.23 g,
2 mmol) and hydroxylamine (50%, 0.20 g, 3 mmol) was stirred at 120 °C for
1.5 h. After nearly complete conversion into an intermediate presumed to be
the corresponding amidoxime (as indicated by TLC), anthranilic acid (0.27 g,
2 mmol) was added to the reaction mixture, which was stirred at 150 °C for a
further 2 h. Next, the reaction mixture was cooled to room temperature and
the product was purified by crystallization from ethanol as colorless crystals,
mp 242 °C (lit 240–242 °C),23 yield: 0.43 g, 91%. EI-MS, m/z (%): 236 (M+, 97),
219 (6), 192 (8), 165 (6), 119 (9), 103 (6), 91 (24), 76 (6), 65 (12). Anal. Calcd for
C15H12N2O (236.27): C, 76.25; H, 5.12; N, 11.86. Found: C, 76.1; H, 5.3; N, 11.7.
1H NMR (500.1 MHz, CDCl3): d 2.47 (3H, s, CH3), 7.38 (2H, d, J = 8.2 Hz, 2CH),
7.50 (1H, dt, J = 1.5, 8.1 Hz, CH), 7.80 (1H, dt, J = 1.5, 8.1 Hz, CH), 7.83 (1H, d,
J = 6.9 Hz, CH), 8.15 (2H, d, J = 8.2 Hz, 2CH), 8.34 (1H, d, J = 7.8 Hz, CH), 11.51
(1H, s, NH). 13C NMR (125.8 MHz, CDCl3): d 21.51 (CH3), 120.83 (C), 126.38,
126.56, 127.25, 127.93, and 129.77 (7CH), 130.00 (C), 134.81 (CH), 142.20,
149.65, and 151.70 (3C), 163.73 (C@O). 2-Benzyl-4(3H)-quinazolinone (4o):
colorless crystals, mp 247–249 °C, yield: 0.44 g, 93%. Anal. Calcd for C15H12N2O
(236.27): C, 76.25; H, 5.12; N, 11.86. Found: C, 76.2; H, 5.2; N, 11.7. 1H NMR
(500.1 MHz, CDCl3): d 3.94 (2H, s, CH2), 7.22 (1H, t, J = 7.2 Hz, CH), 7.30 (2H, t,
22. Narasimhulu, M.; Mahesh, K. C.; Reddy, T. S.; Rajesh, K.; Venkateswarlu, Y.
Tetrahedron Lett. 2006, 47, 4381–4383; Khosropour, A. R.; Mohammadpoor-
Baltork, I.; Ghorbankhani, H. Tetrahedron Lett. 2006, 47, 3561–3564; Salehi, P.;
Dabiri, M.; Zolfigol, M. A.; Baghbanzadeh, M. Tetrahedron Lett. 2005, 46, 7051–
7053; Xue, S.; McKenna, J.; Shieh, W. C.; Repi, O. J. Org. Chem. 2004, 69, 6474–
6477; Kamal, A.; Reddy, K. S.; Prasad, B. R.; Babu, A. H.; Ramana, A. V.
Tetrahedron Lett. 2004, 45, 6517–6521.
23. Arfan, M.; Khan, R.; Anjum, S.; Ahmad, S.; Iqbal Choudhary, M. Chin. Chem. Lett.
2008, 19, 161–165.