反应详情

3,5-Dimethyl-4-[2-(methyloxy)-5-nitrophenyl]isoxazole (for a preparation see Intermediate 1) (43.9 g, 177 mmol) was dissolved in EtOAc (1 liter) diluted with ethanol (1 liter) and added to Pd/C (8 g, 5% w/w, 50% water, Type E101 NO/W) in a 5 liter hydrogenation flask under vacuum, having first purged the vessel twice with vacuum/nitrogen cycles. The mixture was stirred for 24 h. No hydrogen uptake for the first 8-10 h, then steady uptake till approximately 20 liters had been consumed. The mixture purged with vacuum/nitrogen cycle×3 then was filtered through Celite™ under nitrogen and the filtrate evaporated in vacuo to give [3-(3,5-dimethyl-4-isoxazolyl)-4-(methyloxy)phenyl]amine 3-(3,5-dimethyl-4-isoxazolyl)-4-(methyloxy)aniline (38.6 g, 177 mmol, 100% yield) as a brown crystalline solid. LCMS (formate) Rt 0.50 min, MH+ 219

1. customhaving first purged the vessel twice with vacuum/nitrogen cycles
2. customNo hydrogen uptake for the first 8-10 h, then steady uptake till approximately 20 liters had been consumed
3. customThe mixture purged with vacuum/nitrogen cycle×3
4. filtrationthen was filtered through Celite™ under nitrogen
5. customthe filtrate evaporated in vacuo