Hydrochloric Acid → Isotripiperidein

Participants

Reaction Steps

28.6 g (0.2 mol) of 1-formyl-2-methoxypiperidine and 0.3 mol of methanolic HCl were refluxed for 4 hours. At atmospheric pressure in a boiling range of from 30° to 50° C. a mixture of formic acid methyl ester and methanol, which could be re-used for the preparation of 1-formyl-piperidine, was distilled off. The distillation residue was added dropwise to a solution of 21.7 g of KOH (85% strength, 0.33 mol) in methanol and the whole was refluxed for 4 hours. Working up as described in Example 4 yielded 13.3 g (80.1% of the theory) of isotripiperidein melting at 87°-91° C.

Provenance & Evidence