Spectroelectrochemistry of potassium ethylxanthate, bis(ethylxanthato)nickel(II) and tetraethylammonium tris(ethylxanthato)nickelate(II)

Dag, O
Yaman, SO
Önal, Ahmet Muhtar
Isci, H
Electrochemical and chemical oxidation of S2COEt-, Ni(S2COEt)(2), and [Ni(S2COEt)(3)](-) have been studied by CV and in situ UV-VIS spectroscopy in acetonitrile. Cyclic voltammograms of S2COEt- and Ni(S2COEt)(2) display one (0.00 V) and two (0.35 and 0.80 V) irreversible oxidation peaks, respectively, referenced to an Ag/Ag+ (0.10 M) electrode. However, the cyclic voltammogram of [Ni(S2COEt)(3)](-) displays one reversible (- 0.15 V) and two irreversible (0.35, 0.80 V) oxidation peaks, referenced to an Ag/Ag+ electrode. The low temperature EPR spectrum of the oxidatively electrolyzed solution of (NEt4)[Ni(S2COEt)(3)] indicates the presence of [Ni-III(S2COEt)(3)], which disproportionates to Ni(S2COEt)(2), and the dimer of the oxidized ethylxanthate ligand, (S2COEt)(2) ((S2COEt)(2) = C2H5OC(S)SS(S)COC2H5), with a second order rate law. The final products of constant potential electrolysis at the first oxidation peak potentials of S2COEt-, Ni(S2COEt)(2), and [Ni(S2COEt)(3)](-) are (S2COEt)(2); Ni2+(sol) and (S2COEt)(2); and Ni(S2COEt)(2) and (S2COEt)(2), respectively. The chemical oxidation of S2COEt- to (S2COEt)(2), and [Ni(S2COEt)(3)](-) to (S2COEt)(2) and Ni(S2COEt)(2) were also achieved with iodine. The oxidized ligand in the dimer form can be reduced to S2COEt- with CN- in solution.


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Dag, O; Önal, Ahmet Muhtar; Isci, H (1996-06-26)
Electrochemical and chemical oxidation of (Et-Xan(-)), [Ni(Et-Xan)(2)] and [Ni(Et-Xan)(3)](-) (Et-Xan(-) = C2H5OCS2- have been studied by Cyclic Voltammetry and in situ UV-Vis spectroscopy in acetonitrile at room temperature. Cyclic Voltammograms (CV) of Et-Xan(-) and Ni(Et-Xan)(2) display one (0.00 V) and two (0.35 and 0.80 V) irreversible oxidation peaks, respectively, referenced to Ag/Ag+(0.10 M) electrode. However, CV of Ni(Et-Xan)(3)(-) displays one reversible (-0.15 V) and two irreversible (0.35, 0.80...
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Electrochemical and optical properties of novel terthienyl based azobenzene, coumarine and fluorescein containing polymers: Multicolored electrochromic polymers
Yigit, Deniz; Udum, Yasemin Arslan; GÜLLÜ, Mustafa; Toppare, Levent Kamil (Elsevier BV, 2014-01-01)
Three electroactive terthienyl based monomers, namely 1-phenyl-2-[4-(2,2':5',2 ''-terthien-3'-ylmethoxy)phenyl]diazene (TTAz), 4-(2,2':5',2 ''-terthien-3'-ylmethoxy)-2H-chromen-2-one (TTCo) and methyl 2-[3-oxo-6-(2,2':5',2 ''-terthien-3'-ylmethoxy)-3H-xanthen-9-yl] benzoate (TTFlo), were synthesized with good yields and their conducting polymers were electrochemically prepared on ITO electrode surfaces. The effect of chromophore type on electrochemical and optical properties of the polymers was investigated...
Citation Formats
O. Dag, S. Yaman, A. M. Önal, and H. Isci, “Spectroelectrochemistry of potassium ethylxanthate, bis(ethylxanthato)nickel(II) and tetraethylammonium tris(ethylxanthato)nickelate(II),” JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, pp. 2819–2824, 2001, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47652.