17.5 g diphenylpiperidine ethyl acetonitrile, prepared from sodium amide and
2-piperidinoethyl chloride (D.B. Patent No. 710,227) was heated to reflux with
35 g KOH, 70 ml ethanol and 2 ml water for 6 hours. On cooling rich white
crystals dropped. They was filtered off, washed with water to neutral and
dried. Then the product was recrystallized from ethanol. Yield of
diphenylpiperidine ethyl acetamide 15 g. MP: 186°-187°C.
10 g diphenylpiperidine ethyl acetamide was mixed with 42 g of 17% solution
methyl bromide in benzene and 60 ml isopropanol and heated to reflux on a
steam bath for 0.5 hour. The solvent was distilled in vacuum to dryness,
dissolved in 100 ml of water and the very muddy solution was through a coal
filtered. The clear filtrate was distilled off to dryness. Fenpiverinium bromide
was light dissolved in water and had neutral reaction.
