ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Kinetics and mechanisms of the redox reactions of the thallium(III) ions with crotonaldehyde and methacrolein

M. Melicherčík and Ľ. Treindl

Department of Physical Chemistry, Faculty of Natural Sciences, Komenský University, 816 50 Bratislava

Abstract:  The stoichiometry, kinetics, and mechanisms of the redox reactions of thallium(III) sulfate with crotonaldehyde and methacrolein in aqueous solution of sulfuric acid or binary water—dioxan mixture have been studied. A molecule of crotonaldehyde or methacrolein is oxidized by the Tl(III) ions in two consecutive one-electron steps to give 2,3-dihydroxybutyraldehyde or 2,3-dihydroxyisobutyraldehyde. The redox reaction is governed by the rate equation -d[Tl(III)]/dr = k[Tl(III)]ⁿ[S] where n = 0-2. The zero reaction order with respect to the Tl(III) ions may be explained by slow enolization of the hydrated crotonaldehyde and methacrolein which is the rate-determining step and precedes the proper redox step.

Full paper in Portable Document Format: 343a310.pdf

Chemical Papers 34 (3) 310–319 (1980)