Trifluoroacetic acid → ethyl 1-[(R)-2-amino-3-(4-methoxyphenyl)propionyl]-4-cyclohexylpiperidine-4-carboxylate trifluoroacetate

Participants

Reaction Steps

To 10 g (19.4 mmol) of ethyl 1-[(R)-2-tert-butoxycarbonylamino-3-(4-methoxyphenyl)-propionyl]-4-cyclohexylpiperidine-4-carboxylate (cf. preparation 4-3) in 80 ml of dichloromethane are added 20 ml of trifluoroacetic acid. The reaction medium is stirred for 2 hours at room temperature. The solvents are evaporated off and diethyl ether is added in the presence of a few drops of dichloromethane. The precipitate obtained is filtered off and then dried under vacuum at 40° C. 8 g of ethyl 1-[(R)-2-amino-3-(4-methoxyphenyl)propionyl]-4-cyclohexylpiperidine-4-carboxylate trifluoroacetate in the form of a white powder are obtained in a yield of 78%.

Provenance & Evidence