Solvent effect in the chemical design of coordination polymers of various topologies with Co²⁺ and Ni²⁺ ions and 2-furoate anions

Four new frameworks were obtained by slow diffusion of a ligand solution - 1,2-bis(4-pyridyl)ethylene (dpe) into solutions of Ni-II and Co-II furoates. It is shown that, depending on the combination of solvents used, it is possible to purposefully set the topology of the coordination polymers as a simple chain in [Co(fur)(2)(dpe)(CH3OH)(2)](n) (1), 2D 4-c sql in [Co(fur)(2)(dpe)(2)](n) (2)/[Ni(fur)(2)(dpe)(2)](n) (3) and 3D 3-c etb in [Ni(fur)(2)(dpe)(1.5)(H2O)](n)3H(2)O (4) (fur(-) is the anion of 2-furoic acid). The simple chains extend in two different directions. The sql nets show inclined polycatenation. Compound 4 exhibits the first example of such a high degree of interpenetration as 7, which is more than three times higher than the known record for nets. All the compounds were characterized by single crystal X-ray analysis. The metal atoms in the structural fragments have a CN = 6 and are in an octahedral environment with a different ratio of N and O - ({CoO4N2} (1), {MO2N4} for M = Co (2) and Ni (3), {NiO3N3} (4)). The coordination network of 4 has accessible channels with an estimated pore volume of 4650 & Aring;(3) per unit cell (29.4%). Thermal behavior of 1, 3 and 4 was studied by simultaneous thermal analysis (STA). The obtained chi T(T) dependences were approximated using the PHI software. It was shown that interweaving results in the shortening of the metal-metal magnetic interactions.