反应详情

Microwave heat a mixture of tert-butyl 4-(2-oxo-2-phenylethylcarbamoyl)-piperidine-1-carboxylate (1.0 g, 2.88 mmol) and NH4Cl (0.462 g, 8.65 mmol) in ethanol (12 mL) at 300 W, 160° C., and 14 bar for 11 h in a Personal Chemistry microwave. Cool the mixture to room temperature, add silica gel (5 mL), and concentrate the mixture in vacuo. Purify the residue by silica gel chromatography (80 g RediSep column, elute with a gradient of 0% through 100% CMA/methylene chloride over 60 min, 60 mL/min) to provide 4-(4-phenyl-1H-imidazol-2-yl)piperidine (0.418 g, 64%) as an off-white solid. Add 4-(4-phenyl-1H-imidazol-2-yl)piperidine (0.060 g, 0.26 mmol) to methylene chloride (15 mL) and concentrated hydrochloric acid (28 μL). Stir the mixture for 45 min, then concentrate the mixture in vacuo to provide 4-(4-phenyl-1H-imidazol-2-yl)piperidine hydrochloride (0.070 g, 99%).

1. temperatureMicrowave heat
2. additionadd silica gel (5 mL)
3. concentrationconcentrate the mixture in vacuo
4. customPurify the residue by silica gel chromatography (80 g RediSep column
5. washelute with a gradient of 0% through 100% CMA/methylene chloride over 60 min