反应详情

Methylamine (5.0 g, 0.16 mole) was dissolved in a solution of Et2O (100 mL) and EtOH (5 mL) at 0° C., and 2-chloromethylbenzimidazole (13.4 g, 0.08 mole) was added in small portions. The reaction mixture was stirred at RT for 3 h, then was allowed to stand at RT overnight. More Et2O (200 mL) was added, and the reaction was cooled in an ice bath for 3 h before filtering off the precipitate. The filtrate was saturated with HCl and filtered, and the filtrate was concentrated. Silica gel chromatography (step gradient, 10-25% MeOH/CH2Cl2) yielded the title compound (2.5 g, 13%): 1H NMR (250 MHz, 5:1 DMSO-d6 /CDCl3) δ 7.13-7.54 (m, 4H), 4.11 (s, 2H), 2.50 (s, 3H); MS (ES) m/e 162.0 (M+H)+.

1. waitto stand at RT overnight
2. temperaturethe reaction was cooled in an ice bath for 3 h
3. filtrationbefore filtering off the precipitate
4. filtrationfiltered
5. concentrationthe filtrate was concentrated