反应详情

To a stirred suspension of 3-(5-(3,4-dimethoxy-5-nitrophenyl)-4-methyl-4H-1,2,4-triazol-3-yl)-2-(trifluoromethyl)pyridine (0.192 g, 0.47 mmol) in dichloromethane (20 mL) at −78° C. under argon was added boron tribromide (0.47 g, 1.88 mmol) dropwise. The resulting purple suspension was then allowed to stir at room temperature for seven hours before being cooled in an ice-water bath. The mixture was carefully quenched by the addition of methanol. After stirring at room temperature for thirty minutes, the volatiles were evaporated and the residue stirred with 2 N hydrochloric acid (5 mL) for thirty minutes. The resulting solid was filtered off, washed with water (25 mL) and then cold isopropanol (5 mL) to give, after drying, 5-(4-methyl-5-(2-(trifluoromethyl)pyridin-3-yl)-4H-1,2,4-triazol-3-yl)-3-nitrobenzene-1,2-diol was obtained as an orange solid, 0.154 g (86%).

1. temperaturebefore being cooled in an ice-water bath
2. customThe mixture was carefully quenched by the addition of methanol
3. stirringAfter stirring at room temperature for thirty minutes
4. customthe volatiles were evaporated
5. stirringthe residue stirred with 2 N hydrochloric acid (5 mL) for thirty minutes
6. filtrationThe resulting solid was filtered off
7. washwashed with water (25 mL)
8. customcold isopropanol (5 mL) to give
9. customafter drying