反应详情

A mixture of 5-methyl-1-(triphenylmethyl)-1H-imidazole-4-carboxaldehyde (3.2 g) and methylamine hydrochloride (3.6 g) in methanol (60 ml) was stirred at room temperature for 1h. The mixture was then cooled to 0°, treated with sodium cyanoborohydride (0.62 g) for 2h and water (40 ml) was added. The resulting mixture was then stirred at 20° for 0.5h, cooled to 0° and treated with concentrated hydrochloric acid (10 ml). The mixture was then allowed to warm to 20°, and stirred at 20 for a further 1h and basified (to pH9) with potassium carbonate. The alkaline aqueous mixture was diluted with water (100 ml) and extracted with ethyl acetate (×200 ml). The combined organic extracts were dried and evaporated to leave a foam (3.5 g) which was purified by FCC eluting with System A (100:8:1) to give the title compound (1.8 g) as a solid, t.l.c. (System A, 100:3:1) Rf 0.1.

1. temperatureThe mixture was then cooled to 0°
2. additionwas added
3. temperaturecooled to 0°
4. temperatureto warm to 20°
5. extractionextracted with ethyl acetate (×200 ml)
6. customThe combined organic extracts were dried
7. customevaporated