Uranyl Ion Coordination by Benzene‐1,2,3‐tricarboxylate: Building Chains and Networks from Binuclear Bricks

Abstract

AbstractBenzene‐1,2,3‐tricarboxylic acid (123btcH3) was used to synthesize 7 uranyl ion complexes under hydro‐solvothermal conditions, in the presence of different structure‐directing agents. [Zn(phen)3][Zn2(123btc)(phen)4][(UO2)2(123btc)2(OH)(CH3CN)] ⋅ 3H2O (1, phen=1,10‐phenanthroline), the only discrete species in the series, crystallizes as a binuclear, cup‐shaped dimer. Both [PPh3Me][UO2(123btc)] (2) and [C(NH2)3][UO2(123btc)] ⋅ 0.5H2O (3) contain anionic, monoperiodic coordination polymers based on quasi‐planar, binuclear (UO2)2(123btc)22− subunits in which two oxygen atoms of each ligand are uncoordinated. Similar chains are found in [UO2(123btc)K(18C6)] ⋅ H2O (4, 18C6=18‐crown‐6), the potassium cations being decorating groups bound to carboxylato and uranyl oxo donors. An analogous decorating role to monoperiodic polymers is played by UO2(DMF)2(H2O)22+ cations in [(UO2)3(123btc)2(DMF)2(H2O)2] (5), while bridging of chains by UO2(NMP)32+ cations in [(UO2)3(123btc)2(NMP)3] (6) yields a diperiodic network with V2O5 topology. [NH4][UO2(123btc)] (7), which does not contain the dimeric subunit found in the other cases, crystallizes as a diperiodic network with sql topology, the layers being associated through hydrogen bonding interactions with the ammonium counterions.