Synthesis and Stereochemistry of Diastereoisomeric 1,3-Dimethylpiperidin-4-ols and Related Compounds

Abstract

The synthesis of cis and trans 1,3-dimethylpiperidin-4-ols and derived acetate, benzilate, and diphenylacetate esters is described. Configurations and preferred conformations of these derivatives are assigned on the basis of 4-methine and 4-hydroxyl p.m.r. characteristics. Conformational studies of esters of 1-methyl-piperidin-3-ol and isomeric 3-tropanols are also described. Epimeric conjugate acids are well defined in 3-acetoxy-1-methylpiperidine hydrochloride as solute in CDCl₃.