Lactams. XI. Construction of Lactam Carbonyl Function in 1, 3-Disubstituted Piperidines by Mercuric Acetate-EDTA Oxidation : Effects of Carbonyl and Related Groups at the 3-Position

Abstract

1-(3, 4-Dimethyoxyphenyl)-2-(3-substituted piperidino) ethanols (3a-d), which carry the carbamoyl, methoxycarbonyl, acetyl, and 1, 1-ethylenedioxyethyl group as the 3-substituent in the piperidine ring, have been prepared from 3-substituted pyridines (type 1) through 1-(3, 4-dimethoxyphenacyl) pyridinium bromides (type 2). In the mercuric acetate-EDTA oxidation of 3a-d, these 3-substituents have been found to orient the lactam carbonyl formation to the 6-position almost exclusively. It is suggested that the 3-substituents exert both steric and electronic effects.