Redox-active porous coordination polymer based on trinuclear pivalate: Temperature-dependent crystal rearrangement and redox-behavior

Linking of trinuclear pivalate Fe2NiO(Piv)6 (Piv=O2CC(CH3)3) by 2,6-bis(4-pyridyl)-4-(1-naphthyl)pyridine (L) resulted in formation of 1D-porous coordination polymer Fe2NiO(Piv)6(L)·Solv, which was characterized in two forms: DMSO solvate Fe2NiO(Piv)6(L)(DMSO)·2.5DMSO (1) or water solvate Fe2NiO(Piv)6(L)(H2O) (2). X-ray structure of 1 was determined. Crystal lattice of 1 at 160K contained open channels, filled by captured solvent, while temperature growth to 296K led to the crystal lattice rearrangement and formation of closed voids. Redox-behavior of 2 was studied by cyclic voltammetry for a solid compound, deposited on glassy-carbon electrode. Redox-activity of L preserved upon incorporation in the coordination polymer. The presence of pores in desolvated sample Fe2NiO(Piv)6(L) was confirmed by the measurements of N2 and H2 adsorption at 77K. Potential barriers of the different molecules diffusion through pores were estimated by the means of molecular mechanics. Redox-behavior of 1D-porous coordination polymer Fe2NiO(Piv)6(L)(H2O) was studied by cyclic voltammetry in thin film, deposited on glassy-carbon electrode. Redox-activity of L preserved upon incorporation in the coordination polymer. Potential barriers of different molecules diffusion through pores were estimated by the means of molecular mechanics. [Display omitted] •Porous 1D coordination polymer was synthesized.•Temperature growth led to pores closing due to crystal lattice rearrangement.•Redox-activity of ligand preserved upon incorporation into coordination polymer.•Redox-properties of solid coordination polymer were studied in thin film.•Diffusion barriers were evaluated by molecular mechanics.