[NH2:1][C:2]1[CH:3]=[C:4]([CH:10]=[CH:11][N:12]=1)[C:5]([O:7][CH2:8][CH3:9])=[O:6].[C:13](Cl)(=[O:20])[C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1>N1C=CC=CC=1>[C:13]([NH:1][C:2]1[CH:3]=[C:4]([CH:10]=[CH:11][N:12]=1)[C:5]([O:7][CH2:8][CH3:9])=[O:6])(=[O:20])[C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1To a solution of ethyl 2-aminoisonicotinate (1.00 g, 6.02 mmol) in anhydrous pyridine (13 mL) was added benzoyl chloride (0.77 mL, 6.63 mmol) dropwise at 0° C. under nitrogen atmosphere. The resulting solution was warmed to ambient temperature, stirred for 18 hours and concentrated in vacuo. The residue was dissolved in ethyl acetate (75 mL), washed with 2 M aqueous hydrochloric acid solution (20 mL) and saturated aqueous sodium bicarbonate solution (20 mL). The organic solution was dried over anhydrous sodium sulphate, filtered and concentrated in vacuo. The residue was purified by column chromatography eluted with 10-50% ethyl acetate in hexanes to give ethyl 2-benzamidoisonicotinate as a colorless solid (1.35 g, 83%): 1H NMR (300 MHz, CDCl3) δ 8.94 (s, 1H), 8.84 (br s, 1H), 8.43 (d, J=5.1 Hz, 1H), 7.98-7.93 (m, 2H), 7.70-7.47 (m, 4H), 4.44 (q, J=7.1 Hz, 2H), 1.43 (t, J=7.1 Hz, 3H); MS (ES+) m/z 271.5 (M+1).
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