A KINETIC-STUDY OF ACID-CATALYZED OXIDATION OF N-METHY 1-2,6-DIPHENYL-4-PIPERIDONES BY THALLIUM(III) ACETATE

Kinetics of oxidation of 1-methyl-, 1-methyl-3-alkyl- and 1,3,5-trimet hyl-2,6-diphenyl-4-piperidones by thallium(III) acetate have been inve stigated at different temperatures (40-60 degrees) in aqueous acetic a cid (80%, v/v) and sulphuric acid (0.75 mol dm(-3)). Oxidation is foun d to obey second order kinetics which conforms to that reported for Tl -III oxidation of N-H-4-piperidones in our earlier study. Activation p arameters were calculated to substantiate the mechanism. Primary salt- effect was examined using sodium sulphate. The reaction rate increases with the increase in percentage of acetic acid. The possible mechanis m of the reaction has been discussed on the basis of stoichiometry and product isolated.