Alcoholic potash decomposes it into piperidine, C5H,1N, and piperic acid, C 12 H 10 O 4.
The synthesis of piperine follows from the interaction of piperyl chloride (formed from piperic acid and phosphorus pentachloride) and piperidine (L.
Braun (Ber., 1904, 37, p. 35 8 3) has prepared pentamethylene derivatives from piperidine by the action of phosphorus pentachloride.
On heating piperidine with phosphorus pentachloride to 200°C. in a sealed tube pentamethylene dichloride is obtained, and this on treatment with potassium phthalimide gives a condensation product of composition, C 6 H 4 [CO] 2 N(CH 2) 5 N[CO] 2 C 6 H 4, which is finally hydrolysed by hydrochloric acid.
6, p. 329); and by heating piperidine in acetic acid solution with silver acetate (J.