C([O-])(=O)C.[NH4+:5].[CH2:6]([O:8][C:9](=[O:23])[C:10]([NH:12][C:13]1[CH:18]=[CH:17][C:16]([Br:19])=[CH:15][C:14]=1[C:20](=O)[CH3:21])=O)[CH3:7]>C(O)(=O)C>[Br:19][C:16]1[CH:15]=[C:14]2[C:13](=[CH:18][CH:17]=1)[N:12]=[C:10]([C:9]([O:8][CH2:6][CH3:7])=[O:23])[N:5]=[C:20]2[CH3:21]Ammonium acetate (400.0 mg, 5.19 mmol) was added to ethyl[(2-acetyl-4-bromophenyl)amino](oxo)acetate (163.0 mg, 518.9 μmol) in acetic acid (5.2 mL) at room temperature and the reaction was heated at reflux for 19 hours. The reaction mixture was concentrated, then water was added, and the solution was extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, filtered, and concentrated. The residue was purified by silica gel chromatography eluting with 2:3 ethyl acetate:hexanes to give 75.5 mg (49%) of ethyl 6-bromo-4-methyl-2-quinazolinecarboxylate as a solid. 1H NMR (400 MHz, d6-DMSO): δ 8.63 (d, J=2 Hz, 1H), 8.21 (dd, J=9, 2 Hz, 1H), 8.07 (d, J=9 Hz, 1H), 4.41 (q, J=7 Hz, 2H), 2.97 (s, 3H), 1.35 (t, J=7 Hz, 3H). ESI-LCMS m/z 295 (M+H)+.
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