The coordination polymers [Fe 2 MO(piv) 6 (bipy) 1.5 ] n [M = Ni II , compound 1, and M = Co II , compound 2; piv = (CH 3 ) 3 CCO 2 -and bipy = 4,4Ј-bipyridine] were prepared by linking trinuclear heterometallic pivalates, possessing D 3h symmetry, by linear molecules of bipy. The complexes are isostructural and are built from 2D doubly interpenetrated "honeycomb" layers. The structure of the starting polynuclear building blocks is retained, which opens the way for the creation of materials

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International audienceLinking 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– = 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 (SBET = 50 m2 g–1, VDR = 0.017 cm3 g–1 estimated from N2 sorption at 78 K). At 298 K, 2 absorbed a significant quantity of methanol (up to 0.3 cm3 g–1) and chloroform. Temperature dependence of molar magnetic susceptibility of 2 could be fitted as superposition of χMT 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–orbit coupling of CoII, and in the second model the spin–orbit 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

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