[Br:1][C:2]1[CH:3]=[C:4]([CH:8]=[CH:9][C:10]=1[C:11]([O:13][CH3:14])=[O:12])[C:5](O)=[O:6].[NH4+].[Cl-].C[N:18](C(ON1N=NC2C=CC=NC1=2)=[N+](C)C)C.F[P-](F)(F)(F)(F)F.CCN(C(C)C)C(C)C>C(Cl)Cl.O>[Br:1][C:2]1[CH:3]=[C:4]([C:5](=[O:6])[NH2:18])[CH:8]=[CH:9][C:10]=1[C:11]([O:13][CH3:14])=[O:12]A mixture of 3-bromo-4-(methoxycarbonyl)benzoic acid (2.5 g, 9.69 mmol), NH4Cl (1.04 g, 19.38 mmol), HATU (5.5 g, 14.5 mmol), and DIPEA (5.2 mL, 29.1 mmol) in DCM (50 mL) was stirred for 3 h at rt. Water was added and the mixture was extracted with DCM. The combined organic layers were washed with brine, dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by column chromatography over silica gel eluted with PE-EA (3:1) to give methyl 2-bromo-4-carbamoylbenzoate (1.3 g; yield 52%) as a white solid. MS: m/z=257.9 (M+1, ESI+).
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