反应详情

17.4 g (59.2 mmol) of 3-(p-cyanophenyl)-2-isocyanopropionylpiperidine were stirred together with 160 ml of dioxane and 24 ml of concentrated hydrochloric acid at 60° C. for 45-60 min (TLC monitoring, mobile phase CH2Cl2 /CH3OH 9/1), and then the mixture was concentrated under reduced pressure, the residue was taken up in water, the aqueous phase was extracted with a little ethyl acetate, mixed with ammonia and extracted with methylene chloride, and the organic phase was dried over magnesium sulfate and concentrated under reduced pressure. The residue was taken up in acetone, and the hydrochloride was precipitated with hydrochloric acid in ether. The precipitate was filtered off with suction and washed with ether to give 16.3 g (=83%) of p-cyanophenylalaninylpiperidine hydrochloride as white solid.

1. concentrationthe mixture was concentrated under reduced pressure
2. extractionthe aqueous phase was extracted with a little ethyl acetate
3. additionmixed with ammonia
4. extractionextracted with methylene chloride
5. dry with materialthe organic phase was dried over magnesium sulfate
6. concentrationconcentrated under reduced pressure
7. customthe hydrochloride was precipitated with hydrochloric acid in ether
8. filtrationThe precipitate was filtered off with suction
9. washwashed with ether