反应详情

温度

170 °C

A mixture of tert-butyl 4-[(2-oxo-2-phenylethyl)carbamoyl]piperidine-1-carboxylate (5.0 g) and ammonium trifluoroacetate (18.9 g) was stirred at an exterior temperature of 170° C. for 30 minutes. After leaving to be cooled, water and chloroform were added thereto, and the aqueous phase was separated. The aqueous phase was adjusted to a pH of about 10 with a 24% aqueous sodium hydroxide, and extracted with chloroform. The combined organic phase was washed with water and saturated brine, and dried over magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was dried under reduced pressure, and dissolved in DCM (20 mL) and methanol (10 mL), and 4 M hydrogen chloride/dioxane (5.3 mL) was added thereto. The solvent was concentrated under reduced pressure, to the residue was added diisopropyl ether/methanol, and the resulting solid was collected by filtration, and dried under reduced pressure to obtain 4-(4-phenyl-1H-imidazol-2-yl)piperidine dihydrochloride (3.29 g).

1. customAfter leaving
2. temperatureto be cooled
3. customthe aqueous phase was separated
4. extractionextracted with chloroform
5. washThe combined organic phase was washed with water and saturated brine
6. dry with materialdried over magnesium sulfate
7. customthe solvent was evaporated under reduced pressure
8. customThe residue was dried under reduced pressure
9. dissolutiondissolved in DCM (20 mL)
10. additionmethanol (10 mL), and 4 M hydrogen chloride/dioxane (5.3 mL) was added
11. concentrationThe solvent was concentrated under reduced pressure, to the residue
12. additionwas added diisopropyl ether/methanol
13. filtrationthe resulting solid was collected by filtration
14. customdried under reduced pressure