Solvent-induced synthesis of cobalt(ii) coordination polymers based on a rigid ligand and flexible carboxylic acid ligands: syntheses, structures and magnetic properties

Abstract

Five new cobalt(ii) coordination architectures, {[Co(L)2(H2O)2]·2H2O·2NO3}n (), {[Co(L)(ppda)]·2H2O}n (), {[Co2(L)(ppda)2]2·H2O}n (), {[Co(L)(nba)]·5H2O}n (), and {[Co(L)(oba)]2·3H2O}n (), have been constructed from the rigid ligand L [L = 2,8-di(1H-imidazol-1-yl)dibenzofuran] and different flexible carboxylic acid ligands [H2ppda = 4,4'-(perfluoropropane-2,2-diyl)dibenzoic acid, H2nba = 4,4'-azanediyldibenzoic acid, and H2oba = 4,4'-oxydibenzoic acid]. Depending on the nature of the solvent systems, these five different coordination polymers were synthesized and characterized by single-crystal X-ray diffraction, IR, PXRD and elemental analysis. Compounds , and were obtained by a one-pot method, and then we utilized the solvent-induced effect to obtain almost pure crystals of , respectively. Compound is an infinite 1D chain which is formed by L ligands and Co atoms. Compound contains a [Co2(CO2)4] secondary building unit (SBU), and can be topologically represented as a 6-connected 2-fold interpenetrating pcu net with the point symbol of {4(12)·6(3)}. Compound can be characterized as a 4-connected sql tetragonal planar network with the point symbol of {4(4)·6(2)}. In compounds and , there is a 1D chain which is formed by flexible carboxylic acid ligands and Co atoms; then the 1D chain is linked by L ligands in the tilting direction, leading to the formation of a 2D layer. Furthermore, UV-vis, TGA and magnetic properties have been investigated in detail.

Solvent dependent formation of Cu(II) complexes based on isonicotinamide ligand

“…Among them, solvent is one of the key factors concerning its polarity, boiling point, dielectric constant or van der Waals radii, which have a determining effect in the synthesis process [10]. The final product can be modified if solvent acts as ligand [11], as guest [12], as both [13] or simply directs the final structure [14]. For this reason, in most of cases, the solvent of the reaction defines the molecular array and as a result, many efforts have been devoted to research the role of the solvent in the assemblies of coordination compounds [15].…”

Thermodynamic Exploration of Xenon/krypton Separation Based on a High-Throughput Screening

“…To further corroborate the role of the guest-guest interactions, we look at another material with one-dimensional tube-like channels: JUFBIX, a cobalt(II) coordination polymer based on carboxylic acid linkers (see Figure S13). 87 The periodicity along the direction of the tubes is much higher at 7.2 Å. The pair interaction energies corresponding to the LJ potentials at this distance are V Xe-Xe = −0.24 kJ mol −1 , V Kr-Kr = −0.06 kJ mol −1 and V Xe-Kr = −0.13 kJ mol −1 .…”

Soft Templating and Disorder in an Applied 1D Cobalt Coordination Polymer Electrocatalyst

“…Importantly, the number of low-nuclear molecular cobalt complexes explored as water oxidation catalysts remain rather limited to date compared with their extensively studied heterogeneous Co-containing counterparts. Although pentacoordinate binuclear Co(II) complexes containing Co 2 O 3 N 2 motifs have been reported in previous studies, [60][61][62][63] to the best of our knowledge none of these materials have been investigated for their water oxidation catalytic activity. In contrast, pentacoordinate Co-species in solid-state water oxidation catalysts offer unsaturated and accessible edge sites with high affinity for OHspecies in alkaline electrolytes, which strengthens interaction with water molecules and improves electrochemical OER performance.…”