反应详情

A yellow mixture of 2-amino-3-bromobenzoic acid (Oakwood Products, Inc., West Columbia, S.C., 2.07 g, 9.58 mmol), methanamine hydrochloride (0.712 g, 10.54 mmol), 2-(3H-[1,2,3]triazolo[4,5-b]pyridin-3-yl)-1,1,3,3-tetramethylisouronium hexafluorophosphate (V) (4.37 g, 11.50 mmol), and Et3N (3.07 mL, 22.04 mmol) in DMF (19.16 mL) was stirred at RT for 1 h. The reaction mixture was diluted with EtOAc (200 mL), added to a separatory funnel, and washed with saturated aqueous NaHCO3 (2×100 mL); the organic layer was separated, dried over Na2SO4, and concentrated. The crude product in DCM was loaded onto the column and was purified via automated flash chromatography (silica gel) with 0-40% EtOAc in hexanes to give 2-amino-3-bromo-N-methylbenzamide (722a, 1.09 g, 4.76 mmol, 50% yield) as a white solid. 1H NMR (400 MHz, CDCl3) δ ppm 2.97 (d, J=4.89 Hz, 3H) 6.06 (br. s., 3H) 6.52 (t, J=7.92 Hz, 1H) 7.26 (dd, J=7.82, 1.17 Hz, 1H) 7.50 (dd, J=7.92, 1.27 Hz, 1H). MS (ESI, pos. ion) m/z: 228.9/230.9 (M+1).

1. additionadded to a separatory funnel
2. washwashed with saturated aqueous NaHCO3 (2×100 mL)
3. customthe organic layer was separated
4. dry with materialdried over Na2SO4
5. concentrationconcentrated
6. customwas purified