Kinetic Behaviour of some Substituted-4-piperidones towards Oxidation by Aqueous Acidic CrO3
| Main Authors: | (Mrs.) KR. MEENAL, P. ROOPAKALYANI |
|---|---|
| Format: | Article Journal |
| Bahasa: | eng |
| Terbitan: |
, 1988
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| Subjects: | |
| Online Access: |
https://zenodo.org/record/6035166 |
Daftar Isi:
- Department of Chemistry, Seethalakshmi Ramaswami College, Tiruchirapalli-620 002 Manuscript received 25 March 1987, revised 17 May 1988, accepted 8 July 1988 The kinetics of oxidation of N-methyl-2,6-diphenylpiperidone-4, N-methyl-3- methyl-2,6·diphenylpiperidone-4, N-methyl-3-ethyl-2,6-diphenylpiperidone-4, N-methyl-3-isopropyl-2,6-diphenylpiperidone-4, and N-methyl-3,3-dimethyl-2,6-diphenylpiperi- done-4 by aqueous acidic CrO2, have been carried out iodometrically under pseudo·first order conditions in the temperature range 35-50°. The oxidation reaction is found to be first order each with respect to oxidant and substrate. The rate increases with increase in [\(H^+\)] and solvent composition (ACOH) in the reaction mixture. Increase of ionic strength (Na2SO4) increases the rate of reaction. Activation parameters have been evaluated from Arrhenius plot. The results are discussed in terms of a suitable mechanism Involving a rate-determining formation of a chromate ester between CrO2 and substrate followed by the rapid decomposition or the intermediate. The effect of 3-alkyl substituent has been analysed.