Kinetics and mechanism of oxidation of thioglycolic acid (TGA). Thiolactic acid (TLA) and thiomalic acid (TMA) by tripropylammonium fluorochromate (TriPAFC) have been studied in N, N-dimethyl formamide (DMF). The reaction is first order with respect to TriPAFC and thioacids (TA). p-Toluene sulfonic acid (TsOH) is used as a source of hydrogen ions. The reaction is acid catalyzed. The hydrogen ion dependence has the form: k obs = a + b [H + ]. The reaction has been studied in different percentage of DMF-acetic acid mixture. The effect of dielectric constant of the medium indicates the reaction to be of ion-dipole type. Various thermodynamic parameters for the oxidation have been reported and discussed along with the validity of isokinetic relationship. A suitable mechanism has been proposed.

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The oxidation of benzaldehyde (BA) as well as 4-methoxy (4-MBA), 3-methoxy (3-MBA), 2-methoxy (2-MBA), 2,6-dimethoxy (2,6-DMBA), 2,4-dimethoxy (2,4-DMBA), 3,4-dimethoxy (3,4-DMBA), 2,4,6-trimethoxy (2,4,6-TMBA), 3,4,5-trimethoxy (3,4,5-TMBA) and 2,3,4-trimethoxy (2,3,4-TMBA) benzaldehydes by benzimidazolium fluorochromate (BIFC) have been studied in a 50% acetic acid-50% water medium. The oxidation leads to the formation of the corresponding carboxylic acids. The reaction is first order with respect to [BIFC], [S] and [H + ]. The reaction was catalysed by H + ions. The reaction was studied at four different temperatures, and the thermodynamic parameters were calculated. The Exner plot indicated that all of the methoxy-substituted benzaldehydes were oxidized via the same mechanism. Based on the observed kinetics, a suitable mechanism has been proposed.

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