Trifluoroacetic acid → Propionic Acid

Participants

Reaction Steps

A solution of 4-[(1-oxopropy])phenylamino]-piperidine (500 mg, 2.15 mmol) and t-butyl acrylate (0.37 ml, 2.58 mmol), in acetonitrile (2.5 ml) is stirred at room temperature for 24 hours. The solution is concentrated and the residue is chromatographed on silica gel (EtOAc) to give 4-[2-[(1-oxopropyl)phenylamino]-1-piperidine propanoic acid, t-butyl ester as an oil: 605 mg, 78%. To the ester (309 mg, 0.857 mmol) is added trifluoroacetic acid (4 ml). The homogeneous reaction mixture is stirred at room temperature for one hour and then concentrated to an oil which is triturated with ether to give a white solid, 3-[4-[(1-oxopropyl)phenylamino]-1-piperi]-dine]propanoic acid, trifluoroacetate: 316 mg, 88%; m.p. 187°-189° C.

Provenance & Evidence