Synthesis of 4-substituted 1-methyl(benzyl)-2,5-dimethyl-4-R-aminopiperidines

Schiff base derivatives of 1-methyl(benzyl)-2,5-dimethylpiperidin-4-ones with phenyl, α-pyridyl, benzyl, and Β-hydroxyethyl substituents attached to the imine nitrogen atom react with organometallic compounds to give analogously substituted piperidine bases with methyl, allyl, phenyl, and benzyl substituents in the 4-position. Pure individual geometric isomers of these newly synthesized compounds have been isolated and their structures determined. © 1988 Plenum Publishing Corporation.