反应详情

Add tert-butyl 4-(2-oxo-2-(3-(trifluoromethoxy)phenyl)ethylcarbamoyl)-piperidine-1-carboxylate (1.50 g, 3.48 mmol) to a mixture of ammonium acetate (1.40 g, 18.1 mmol), and glacial acetic acid (10 mL) and heat at reflux for 15 h. Cool the mixture to room temperature and concentrated in vacuo. Dissolve the residue in ethyl acetate (50 mL) and adjust to pH 8 with saturated NaHCO3. Extract the aqueous layer with ethyl acetate (2×50 mL). Combine the organic layers, dry (Na2SO4), filter, and concentrate in vacuo. Purify the residue by silica gel chromatography (80 g, eluting with a gradient of 10% to 20% methanol/ethyl acetate, 1.5 L) to provide 4-(4-(3-(trifluoromethoxy)phenyl)-1H-imidazol-2-yl)piperidine (491 mg, 45%).

1. temperatureheat
2. temperatureat reflux for 15 h
3. concentrationconcentrated in vacuo
4. dissolutionDissolve the residue in ethyl acetate (50 mL)
5. extractionExtract the aqueous layer with ethyl acetate (2×50 mL)
6. dry with materialCombine the organic layers, dry (Na2SO4)
7. filtrationfilter
8. concentrationconcentrate in vacuo
9. customPurify the residue by silica gel chromatography (80 g
10. washeluting with a gradient of 10% to 20% methanol/ethyl acetate, 1.5 L)