Redox-Active Porous Coordination Polymers Prepared by Trinuclear Heterometallic Pivalate Linking with the Redox-Active Nickel(II) Complex: Synthesis, Structure, Magnetic and Redox Properties, and Elec

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• 作者：A. S. Lytvynenko ; S. V. Kolotilov ; M. A. Kiskin ; O. Cador ; S. Golhen ; G. G. Aleksandrov ; A. M. Mishura ; V. E. Titov ; L. Ouahab ; I. L. Eremenko ; V. M. Novotortsev
• 刊名：Inorganic Chemistry
• 出版年：2014
• 出版时间：May 19, 2014
• 年：2014
• 卷：53
• 期：10
• 页码：4970-4979
• 全文大小：490K
• 年卷期：v.53,no.10(May 19, 2014)
• ISSN：1520-510X

文摘

Linking of the trinuclear pivalate fragment Fe₂CoO(Piv)₆ by the redox-active bridge Ni(L)₂ (compound 1; LH is Schiff base from hydrazide of 4-pyridinecarboxylic acid and 2-pyridinecarbaldehyde, Piv^{鈥?/sup> = pivalate) led to formation of a new porous coordination polymer (PCP) {Fe₂CoO(Piv)₆}{Ni(L)₂}_1.5 (2). X-ray structures of 1 and 2 were determined. A crystal lattice of compound 2 is built from stacked 2D layers; the Ni(L)₂ units can be considered as bridges, which bind two Fe₂CoO(Piv)₆ units. In desolvated form, 2 possesses a porous crystal lattice (S_BET = 50 m2 g鈥?, V_DR = 0.017 cm3 g鈥? estimated from N₂ sorption at 78 K). At 298 K, 2 absorbed a significant quantity of methanol (up to 0.3 cm3 g鈥?) and chloroform. Temperature dependence of molar magnetic susceptibility of 2 could be fitted as superposition of 蠂_MT of Fe₂CoO(Piv)₆ and Ni(L)₂ units, possible interactions between them were taken into account using molecular field model. In turn, magnetic properties of the Fe₂CoO(Piv)₆ unit were fitted using two models, one of which directly took into account a spin鈥搊rbit coupling of CoII, and in the second model the spin鈥搊rbit coupling of CoII was approximated as zero-field splitting. Electrochemical and electrocatalytic properties of 2 were studied by cyclic voltammetry in suspension and compared with electrochemical and electrocatalytic properties of a soluble analogue 1. A catalytic effect was determined by analysis of the catalytic current dependency on concentrations of the substrate. Compound 1 possessed electrocatalytic activity in organic halide dehalogenation, and such activity was preserved for the Ni(L)₂ units, incorporated into the framework of 2. In addition, a new property occurred in the case of 2: the catalytic activity of PCP depended on its sorption capacity with respect to the substrate. In contrast to homogeneous catalysts, usage of solid PCPs may allow selectivity due to porous structure and simplify separation of product.}