反应详情

A suspension of 200 mg of 1-(4-hydroxy-3,5-di-tert.-butylbenzoylamino)-2-methyl-1H-imidazole in 10 ml of anhydrous tetrahydrofuran is treated under an inert gas with 1.2 ml of a 2N borane-dimethyl sulfide complex solution in toluene. The mixture is then heated at reflux for 4 hours, left to cool to 0°, treated with methanolic hydrochloric acid (5 ml of methanol and 0.5 ml of conc. HCl), and again heated at reflux for 1 hour and evaporated in a vacuum. The residue is taken up in 4 ml of water and saturated sodium bicarbonate solution is added until the pH amounts to 8-9. The mixture is extracted three times with 5 ml of methylene chloride each time and, after drying, the combined methylene chloride phases are evaporated. The residue is recrystallized from cyclohexane and there is obtained 1-(4-hydroxy-3,5-di-tert.-butylbenzylamino)-2-methylimidazole of m.p. 180°.

1. temperatureThe mixture is then heated
2. temperatureat reflux for 4 hours
3. waitleft
4. temperatureto cool to 0°
5. temperatureagain heated
6. temperatureat reflux for 1 hour
7. customevaporated in a vacuum
8. additionsaturated sodium bicarbonate solution is added until the pH amounts to 8-9
9. extractionThe mixture is extracted three times with 5 ml of methylene chloride each time
10. customafter drying
11. customthe combined methylene chloride phases are evaporated
12. customThe residue is recrystallized from cyclohexane