反应详情

2-Amino-5-bromobenzoic acid (4.0 g, 0.018 mol) was dissolved in DMF (90 mL) and treated with carbonic acid di-tert-butyl ester (4.44 g, 0.020 mol), 4-dimethylaminopyridine (0.219 g, 0.0018 mol) and triethylamine (2.8 mL, 0.020 mol) for 16 h at 70° C. The mixture was concentrated in vacuo and the residue was dissolved in ethyl acetate, washed twice with saturated aqueous sodium bicarbonate, then twice with 1 N hydrochloric acid, dried over sodium sulfate. The organic layers were concentrated to afford 5-bromo-2-tert-butoxycarbonylamino-benzoic acid as a yellow solid (4.92 g, 86.7%). 1H NMR (500 MHz, DMSO-d6) δ 1.46 (s, 9H), 7.72 (dd, J=2.5, J=8.5 Hz, 1H), 8.01 (d, J=2.5 Hz, 1H), 8.22 (d, J=8.5 Hz, 1H), 10.44 (s, 1H). MS: m/z 316 (M+H+).

1. concentrationThe mixture was concentrated in vacuo
2. dissolutionthe residue was dissolved in ethyl acetate
3. washwashed twice with saturated aqueous sodium bicarbonate
4. dry with materialtwice with 1 N hydrochloric acid, dried over sodium sulfate
5. concentrationThe organic layers were concentrated