Electroreduction of 4-(2-Thienyl)quinazoline in Acetonitrile
01 Jan 1982-Bulletin of the Chemical Society of Japan (The Chemical Society of Japan 公益社団法人 日本化学会)-Vol. 55, Iss: 1, pp 286-288
TL;DR: In this paper, a disproportionation reaction mechanism was proposed for 4-TQ reduction in acetonitrile, based on controlledpotential electrolysis and cyclic voltammetric experiments.
Abstract: The electroreduction of 4-(2-thienyl)quinazoline (4-TQ) in acetonitrile solutions gave a single two-electron well-defined polarographic wave. The well-defined wave was found to be diffusion-controlled and irreversible on the basis of the usual criteria. Based on the controlled-potential electrolysis and cyclic voltammetric experiments, a disproportionation reaction mechanism is suggested for 4-TQ reduction in acetonitrile.
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TL;DR: In this article, the rates of oxidation of PTAA and several substituted phenylthioacetic acids by potassium peroxodiphosphate (PP) in 50% (v/v) aqueous acetic acid have been studied in detail.
Abstract: The rates of oxidation of phenylthioacetic acid (PTAA) and several substituted phenylthioacetic acids by potassium peroxodiphosphate (PP) in 50% (v/v) aqueous acetic acid have been studied in detail. The rate of oxidation is expressed as
An analysis of the dependence of the rate on [H+] reveals that H3P2O is the active oxidizing species in the oxidation. The effect of ring substituents on the rate gives a ρ+ value of -0.45 ± 0.03 (r = 0.998, s = 0.02 at 40°C), pointing to the development of an electron-deficient center in the transition state. The results are discussed in terms of a mechanism involving the rate-determining formation of an intermediate between PP and phenylthioacetic acids, followed by the decomposition of the intermediate. These kinetic results are compared with those obtained in the oxidation of phenylthioacetic acids by peroxodisulfate.
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TL;DR: In this paper, the electrochemical behavior of 4(2′-thienyl)quinazoline (4TQ) was studied in acid solutions of varying ionic strengths using polarography, cyclic voltammetry and controlled-potential electrolysis.
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2,826 citations
TL;DR: In this paper, the Anderson-Weiss model for motional narrowing has been used to calculate the hyperfine structure of electrochemically generated mononegative ion radicals of the type [Complex chemical formula] where X = CH2, S, O, CH2CH2, and X is absent.
Abstract: The hyperfine structure of electrochemically generated mononegative ion radicals of the type [Complex chemical formula] has been observed, where X=CH2, S, O, CH2CH2, and where X is absent. The hyperfine structure is found to be especially sensitive to the intramolecular electron transfer rate when the latter is the same order of magnitude as the hyperfine intervals when expressed as frequencies. The transfer rate is found to be sensitive to the solvent, and a model is presented that expresses the trapping of the electronic charge by the orientation of solvent dipoles. The mechanism for electron transfer then proceeds through the random motions of the solvent molecules.Hyperfine structures are calculated for a series of transfer rates on the basis of the Anderson—Weiss model for motional narrowing. Good agreement is found between the unusual hyperfine structure observed experimetally and the calculated spectra for certain values of the transfer rate.The shape of the composite two‐electron polarographic red...
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