Kinetic evidence of a common mechanism in the oxidations of diethyl sulfide by dichromates and halochromates of heterocyclic bases

Abstract

The oxidations of diethyl sulfide by potassium dichromate, pyridinium dichromate, quinolinium dichromate, imidazolium dichromate, nicotinium dichromate, isonicotinium dichromate, pyridinium fluorochromate, quinolinium fluorochromate, imidazolium fluorochromate, pyridinium chlorochromate, quinolinium chlorochromate, and pyridinium bromochromate follow identical kinetic orders-first-order each with respect to the chromium(VI) reagents, sulfide and hydrogen ion, and moderately inhibited by manganese(II) ion. The energy of activation varies linearly with the logarithm of frequency factor and so does the enthalpy of activation with the entropy of activation. Also, the activation free energies do not differ significantly. The dichromates and halochromates of heterocyclic bases oxidize diethyl sulfide via a common mechanism. C

Spectral Evidence for the One-Step Three-Electron Oxidation of Phenylsufinylacetic Acid and Oxalic Acid by Cr(VI)

“…However, it is observed that in the lower regions of [Cr(VI)], the pseudo-first order rate constant increases with decrease in [Cr(VI)] ( Table 1). Such type of decrease in rate with increase in [Cr(VI)] has been observed by several researchers [33][34][35][36]. However, the rate constants remain constant at higher concentration range of Cr(VI).…”

“…However, the rate constants remain constant at higher concentration range of Cr(VI). The decrease in rate with increase in Cr(VI) in lower concentration region may be due to the dimerization of Cr(VI) followed by decrease in concentration of active species [33][34][35] or due to the existence of some sort of weak association between monomeric Cr(VI) species [36]. The reaction is first order each in PSAA and oxalic acid, which are evidenced from the constant values obtained by dividing k 1 Table T1) and shows a first order dependence with respect to [H + ].…”

Influence of Homocysteine on the Function of Native Arteriovenous Fistula in Hemodialysis Patients

“…So are those dealing with the structure–reactivity relationships operating in these oxidations 8, 9. But reports on comparison of the rates and mechanisms of oxidations of a substrate by these reagents are a few; diphenyl sulfide in glacial acetic acid 10, diethyl sulfide 11, benzyl alcohol 12, 2‐propanol 13, and 1‐pentanol 14 in aqueous acetic acid individually exhibit identical kinetic behavior on oxidation with dichromates and halochromates of heterocyclic bases. Here, for the first time, we compare the reaction constants of the oxidations by dichromates, fluorochromates, chlorochromates, and bromochromate of heterocyclic bases; primary aliphatic alcohols have been chosen for the study, as the oxidation mechanism has been elucidated recently 14.…”

Similar substituent effects in the oxidations of primary aliphatic alcohols with dichromates and halochromates of heterocyclic bases

“…So are those dealing with the structure-reactivity relationships operating in these oxidations [8,9]. But reports on comparison of the rates and mechanisms of oxidations of a substrate by these reagents are a few; diphenyl sulfide in glacial acetic acid [10], diethyl sul- fide [11], benzyl alcohol [12], 2-propanol [13], and 1-pentanol [14] in aqueous acetic acid individually exhibit identical kinetic behavior on oxidation with dichromates and halochromates of heterocyclic bases. Here, for the first time, we compare the reaction constants of the oxidations by dichromates, fluorochromates, chlorochromates, and bromochromate of heterocyclic bases; primary aliphatic alcohols have been chosen for the study, as the oxidation mechanism has been elucidated recently [14].…”