Water → HCID 13094214, compound

Participants

Reaction Steps

A mixture of 10.9 parts of ethyl 1-[4-cyano-4-(4-fluorophenyl)-1-cyclohexyl]-4-phenyl-4-piperidinecarboxylate, 11.2 parts of potassium hydroxide, 50 parts of water and 96 parts of 2-propanol is stirred and refluxed for 4 hours. The reaction mixture is filtered hot over Hyflo and the filtrate is poured onto 300 parts of water. The whole is neutralized with acetic acid to pH 6-7. The precipitated product is filtered off, washed three times with water and converted into the hydrochloride salt in ethanol and 2-propanol. The salt is filtered off and suspended in a solution of 1.4 parts of potassium hydroxide in 150 parts of water. The free base is extracted four times with 70 parts of 1,1'-oxybisethane. The aqueous phase is separated and stirred for a while on a rotavapor to remove all traces of 1,1'-oxybisethane. The clear aqueous phase is acidified with a 10% acetic acid solution to pH 6. The precipitated product is filtered off, washed with water and dried overnight at about 105° C., yielding 5.4 parts (66.4%) of 1-[4-cyano-4-(4-fluorophenyl)cyclohexyl]-4-phenyl-4-piperidinecarboxylic acid; mp. 281.1° C.

Provenance & Evidence