5281-77-6Relevant academic research and scientific papers
Kinetics and mechanism of the oxidation of diols by butyltriphenylphosphonium dichromate
Panday, Dinesh,Kothari, Seema
experimental part, p. 918 - 925 (2011/09/19)
The oxidation of four vicinal, four non-vicinal diols and one of their monoethers by butyltriphenylphosphonium dichromate (BTPPD), in dimethylsulfoxide (DMSO), resulted in the formation of corresponding hydroxyaldehyde as a main product of the oxidation. The reactions are of first order with respect to BTPPD, however, second order dependence is obtained with respect to each the diol and hydrogen ion. The oxidation of [1,1,2,2-2H 4]ethanediol exhibited primary kinetic isotope effect (k H/kD = 6.61 at 298 K). The temperature dependence of the kinetic isotope effect suggested the symmetrical transition state in the rate-determining step. The rate constants of oxidation of four vicinal diols show excellent correlation with Taft's ∑ σ* values with negative reaction constant, ρz.ast;. The rate of oxidation of ethanediol has been determined in nineteen different solvents. An analysis of the solvent effect indicates the importance of the cation-solvating power of the solvents. A suitable mechanism has been postulated involving the formation of chromate ester in a pre-equilibrium.
Oxidation of some vicinal and non-vicinal diols by morpholinium chlorochromate: A kinetic and mechanistic study
Barthora,Baghmar,Agarwal,Sharma, Vinita
experimental part, p. 677 - 683 (2012/04/10)
The kinetics of oxidation of four vicinal, four non-vicinal diols and two of their monoethers by morpholinium chlorochromate (MCC) have been studied in dimethylsulphoxide (DMSO). The main product of oxidation is the corresponding hydroxycarbonyl compound. The reaction is first order in MCC and the diols. The reaction is catalysed by hydrogen ions. The hydrogen ion dependence is taking the form : kobs = a + b [H+]. The oxidation of [1,1,2,2-2H4]ethanediol exhibits a substantial primary kinetic isotope effect (kH/kD = 5.82 at 298 K). The reaction has been studied in nineteen different organic solvents and the solvent effect has been analysed using Taft's and Swain's multiparametric equations. The temperature dependence of the kinetic isotope effect indicates the presence of a symmetrical transition state in the rate-determining step. A suitable mechanism has been proposed.
