Zwitterionic and Anionic Polycarboxylates as Coligands in Uranyl Ion Complexes, and Their Influence on Periodicity and Topology

The three zwitterionic di- and tricarboxylate ligands 1,1'-[(2,3,5,6-tetramethylbenzene-1,4-diyl)bis(methylene)]bis(pyridin-1-ium-4-carboxylate) (pL1), 1,1'-[(2,3,5,6-tetramethylbenzene-1,4-diyl)bis-(methylene)]bis(pyridin-1-ium-3-carboxylate) (mL1), and 1,1',1 ''-[(2,4,6-trimethylbenzene-1,3,5-triyl)tris(methylene)] tris (pyridin-1-ium-4-carboxylate) (L2) have been used as ligands to synthesize a series of 15 uranyl ion complexes involving various anionic coligands, in most cases polycarboxylates. [(UO2)(2)(pL1)(2)(cbtc)(H2O)(2)]center dot 10H(2)O (1, cbtc(4-) = cis,trans,cis-1,2,3,4-cyclobutanetetracarboxylate) is a discrete, dinuclear ring-shaped complex with a central cbtc(4-) pillar. While [UO2(pL1)(NO3)(2)] (2), [UO2(pLl)(OAc)(2)] (3), and [UO2(pL1)(HCOO)(2)] (4) are simple chains, [(UO2)(2)(mL1)(1,3-pda)(2)] (5, 1,3-pda(2-) = 1,3-phenylenediacetate) is a daisy chain and [UO2(pL1)(pdda)](3)center dot 10H(2)O (6, pdda(2-) = 1,2-phenyl-enedioxydiacetate) is a double-stranded, ribbon-like chain. Both [UO2(pL1)(pht)].5H(2)O (7, pht(2-) = phthalate) and [(UO2)(3)(mL1)(pht)(2)(OH)(2)] (8) crystallize as diperiodic networks with the sql topology, the latter involving hydroxo-bridged trinuclear nodes. [(UO2)(2)(pL1)(c/t-1,3-chdc)(2)] (9, c/t-1,3-chdc(2-) = cis/trans-1,3-cydohexanedicarboxylate) and [UO2(pL1)(t-1,4-chdc)]center dot 1.5H(2)O (10, t-1,4-chdc(2-) = trans-1,4-cyclohexanedicarboxylate) are also diperiodic, with the V2O5 and sql topologies, respectively. Both [(UO2)(2)(mL1)(c/t-1,4-chdc)(2)] (11) and [(UO2)(2)(pL1)(1,2-pda)(2)] (12, 1,2-pda(2-) = 1,2-phenylenediacetate) crystallize as diperiodic networks with hcb topology, and they display threefold parallel interpenetration. [HL2] [(UO2)(3)(L-2)(adc)(3)] Br (13, adc(2-) = 1,3-adamantanedicarboxylate) contains a very corrugated hcb network with two different kinds of cells, and the uncoordinated HL2(+) molecule associates with the coordinated L2 to form a capsule containing the bromide anion. [(UO2)(2)(pL1)(kpim)(2)] (14, kpim(2-) = 4-ketopimelate) is a three-periodic framework with pL1 molecules pillaring fes diperiodic subunits, whereas [(UO2)(2) (L2)(2) (t-1,4-chdc)](NO3)(1.7)Br-0.3 center dot 6H(2)O (15), the only cationic complex in the series, is a triperiodic framework with dmc topology and t-1,4-chdc(2-) anions pillaring fes diperiodic subunits. Solid-state emission spectra and photoluminescence quantum yields are reported for all complexes.

Automated summary

A series of uranium ion complexes involving various anionic coligands have been synthesized using zwitterionic ligands. These complexes exhibit different crystal structures and optical properties in the solid state.