反应详情

To a solution of 1-(cyclopropylmethyl)-2-(4-ethoxybenzyl)-1H-benzimidazole-5-carbonitrile (500 mg, 1.51 mmol) in 1:1 EtOH:H2O (16 mL) was added KOH (338 mg, 6.04 mmol). The resulting mixture was refluxed for 36 h. The mixture was acidified with 1 N HCl to pH˜6.0, the precipitate was collected by filtration to give white solids (520 mg, 99%) which was used for the next step without further purification. The analytically pure compound was obtained by recrystallization (from EtOH:H2O). 1H NMR (400 MHz, CD3OD): δ 8.25 (s, 1H), 7.89 (d, J=8.4 Hz, 1H), 7.47 (d, J=8.4 Hz, 1H), 7.18 (d, J=8.2 Hz, 2H), 6.82 (d, J=8.2 Hz, 2H), 4.28 (s, 2H), 4.06 (d, J=6.8 Hz, 2H), 3.89 (q, J=7.6 Hz, 2H), 1.32 (t, J=7.6 Hz, 3H), 1.06–0.92 (m, 1H), 0.50–0.48 (m, 2H), 0.32–0.26 (m, 2H). MS (ESI) (M+H)+=351. Anal. Calcd for C21H22N2O3.0.7HCl: C, 67.09; H, 6.09; N, 7.45. Found: C, 66.98; H, 6.31; N, 7.09.

1. temperatureThe resulting mixture was refluxed for 36 h
2. filtrationthe precipitate was collected by filtration