[Synthesis]
At room temperature, 2-(aminomethyl)-5-bromoaniline (0.90 g, 4.5 mmol) was dissolved in tetrahydrofuran (10 mL), followed by the addition of N,N'-carbonyldiimidazole (0.80 g, 4.9 mmol). The reaction mixture was heated to 80 °C with continuous stirring for 6 hours. Upon completion of the reaction, the mixture was cooled to room temperature, the resulting solid was collected by filtration and washed with ether to afford 7-bromo-3,4-dihydroquinazolin-2(1H)-one (0.73 g, 72% yield) as an off-white solid.IR (KBr) νmax/cm-1 : 3308, 3158 (NH), 3022 (Ar-H), 1682 (C=O). 1514, 1411 (C=C).1H NMR (500 MHz, DMSO-d6) δ: 5.25 (s, 2H, CH2); 6.82 (d, 1H, J=8.2 Hz, H-5); 7.42 (m, 2H, H-4, H-6); 10.29 (br.s, 1H, NH).13C NMR (125.7 MHz. DMSO-d6) δ: 66.85 (CH2), 113.70 (C-10), 115.70 (C-8), 121.03 (C-7), 127.52 (C-6), 131.41 (C-5), 135.88 (C-9), 151.42 (C=O). Elemental analysis calculated values (%) C8H7BrN2O (225.97): C: 42.32, H: 3.11, N: 12.34; measured values (%): C: 42.27, H: 3.16, N: 12.28. |