Hydrochloric Acid → 2-Phenyl-3-(3-piperidinopropionyl)benzofuran

Participants

Reaction Steps

To a solution of 47.2 grams of 2-phenyl-3-acetylbenzofuran in 120 milliliters of isopropanol were added 6 grams of paraformaldehyde, 29.1 grams of piperidine hydrochloride and 6 milliliters of a saturated solution of hydrogen chloride in ethanol and the mixture was heated under reflux for a period of 10 hours. The solvent was evaporated from the resulting mixture under vacuum and the residue was triturated with ethyl ether. The portion of the residue that was insoluble in ether was separated from the ether extract and was dissolved in water. The aqueous solution was then made alkaline by addition thereto of a 5% aqueous solution of sodium hydroxide and the base that thus precipitated was extracted with ethyl ether and the extract was dried by addition of anhydrous sodium sulfate thereto. Upon addition to the ether extract of a solution of hydrogen chloride in ethanol, the hydrochloride of the compound named in the heading of this example precipitated, and it was separated by suction filtration and dried. it weighed 22.7 grams and, after recrystallization from ethanol, had a melting point of 173°-174°C.

Provenance & Evidence