Redox properties and electron transfer in a triarylamine-substituted HS-Co2+/LS-Co3+ redox couple.
Redox properties and electron transfer in a triarylamine-substituted HS-Co2+/LS-Co3+ redox couple.
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三芳胺取代的 HS-Co2 /LS-Co3 氧化还原电对的氧化还原性质和电子转移
DOI:
10.1039/c6dt04748c
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发表时间:
2017
影响因子:
4
通讯作者:
M. Korb
中科院分区:
文献类型:
--
作者:
L. Schnaubelt;H. Petzold;J. M. Speck;E. Dmitrieva;M. Rosenkranz;M. Korb
A new tridentate phenanthroline-pyridyl-based ligand 1 containing a redox active Tara (triaryl amine) unit has been developed (1 = 4-((6-(1,10-phenanthrolin-2-yl)pyridin-2-yl)oxy)-N,N-di-p-tolylaniline). The complex [Co2+(1)2](ClO4/BF4)2 was prepared and the order of the oxidation steps was analysed by cyclic voltammetry and EPR/UV-vis-NIR spectroelectrochemistry. Oxidation of [Co2+(1)2]2+ to [Co3+(1+)2]5+ proceeds in two steps. The first step is the Co2+/3+ centred oxidation to [Co3+(1)2]3+ (E°′(M2+/3+) = 284 mV vs. Fc/Fc+) followed by oxidation of the Tara0/+ centres (E°′(Tara) = 531 mV). Both kinds of oxidation processes were independently investigated in the analogous complexes [Zn(1)2](ClO4)2 and [Co(2)2](BF4)2 allowing an assignment of changes in the electronic spectra to the redox states (2 = 2-(6-phenoxypyridin-2-yl)-1,10-phenanthroline). Although spectroelectrochemistry did not indicate substantial coupling between the redox centres the Tara unit is an efficient mediator for the self-exchange in the [Co2+/3+(1)2]2+/3+ couple. The electron transfer by self-exchange in [Co2+/3+(1)2]2+/3+ was further investigated by variable temperature (VT) 1H NMR spectroscopy. In addition, the resonances found in the paramagnetic proton NMR spectra were assigned by using COSY, T1 and EXSY measurements in combination with the Co–N distances obtained from X-ray analysis. [Co(1)2]2+ is found in the HS state. In contrast, the Fe2+ species [Fe(1)2](ClO4)2 is a spincrossover system. The SCO was analysed in solution by VT 1H NMR and VT/vis spectroscopy.
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影响因子:
4.6
作者:
Jeffrey J. Moore;John J Nash;P. Fanwick;D. McMillin
通讯作者:
Jeffrey J. Moore;John J Nash;P. Fanwick;D. McMillin
影响因子:
20.6
作者:
Hayami, Shinya;Komatsu, Yasuka;Lee, Young Noon
通讯作者:
Lee, Young Noon
影响因子:
4.6
作者:
W. Klaeui;W. Eberspach;P. Guetlich
通讯作者:
P. Guetlich
DOI:
--
发表时间:
2014
期刊:
影响因子:
--
作者:
Silvio Heider;H. Petzold;J. Speck;T. Rüffer;Dieter Schaarschmidt
通讯作者:
Dieter Schaarschmidt
影响因子:
20.6
作者:
A. Vogler;A. Osman;H. Kunkely
通讯作者:
H. Kunkely