cis-1,2-Cyclohexanedicarboxylic acid ( c-chdcH) was reacted with uranyl nitrate under (solvo-)hydrothermal conditions in the presence of different possible counterions. Two neutral complexes of 1:1 stoichiometry were obtained, [UO( c-chdc)(DMF)] (1) and [UO( c-chdc)(HO)] (2), which crystallize as two-dimensional coordination polymers and do not include the additional cations present in solution. In contrast, the complex [NH][PPh][(UO)( c-chdc)(HO)]·3HO (3) crystallized in the presence of PPhBr, ammonium cations being generated in situ from acetonitrile hydrolysis. This complex of 8:9 uranium:ligand stoichiometry contains an octanuclear anionic cage of D symmetry with a pseudo-cubic arrangement of uranium atoms. The ammonium cation is held within the cage through four hydrogen bonds with uranyl oxo groups directed inward. This cage complex is luminescent, although with a low quantum yield of 0.06, indicating limited potential as a photo-oxidant of included species.

under solvo-hydrothermal conditions and in the presence of [M(L)n] q+ cations, in which M = transition metal cation, L = 2,2ʹ-bipyridine (bipy) or 1,10-phenanthroline (phen), n = 2 or 3, and q = 1 or 2, gave ten complexes which have been crystallographically characterized. The diacetate ligands are bis-chelating and the uranyl cations are tris-chelated in all cases. [UO2(1,2-PDA)2Zn(phen)2]⋅2H2O (1) and [UO2(1,4-PDA)2Mn(bipy)2]⋅H2O (2) are heterometallic, neutral one-dimensional (1D) coordination polymers in which the carboxylate-coordinated 3d block metal cation is either decorating only (1), or participates in polymer building (2). [Zn(phen)3][(UO2)2(1,3-PDA)3] (3) and [Ni(phen)3][(UO2)2(1,4-PDA)3]⋅H2O (4), with separate counterions, crystallize as anionic twodimensional (2D) networks, as does [Cu(bipy)2][H2NMe2][(UO2)2(1,4-PDA)3] (5), which displays parallel 2D interpenetration. The complex [Zn(phen)3][(UO2)2(1,2-PDA)3]⋅7H2O (6) crystallizes as a ladderlike, slightly inflated ribbon. The same topology is found in [Zn(bipy)3][(UO2)2(1,3-PDA)3] (7), but the larger separation between coordination sites and the coexistence of curved and divergent ligand conformations produce a tubelike assembly. An analogous, but more regular and spacious tubular geometry is found in [M(bipy)3][(UO2)2(1,4-PDA)3] with M = Co (8) or Ni (9), and {Λ-[Ru(bipy)3]}[(UO2)2(1,4-PDA)3] (10). The disordered counterions in 8 and 9 are replaced by well-ordered, enantiomerically pure chiral counterions in 10. The tubular assemblies formed in 7-10 are characterized by an oblong section and the presence of gaps in the walls, which enable the inclusion of two rows of counterions in the cavity.

Nine uranyl ion complexes were synthesized under (solvo-)hydrothermal conditions using α,ωdicarboxylic acids HOOC-(CH2)n-2-COOH (H2Cn, n = 6-9) and diverse counterions. Complexes [PPh4][UO2(C6)(NO3)] (1) and [PPh4][UO2(C8)(NO3)] (2) contain zigzag one-dimensional (1D) chains, further polymerization being prevented by the terminal nitrate ligands. [PPh3Me][UO2(C7)(HC7)] (3) crystallizes as a 1D polymer with a curved section, hydrogen bonding of the uncomplexed carboxylic groups giving rise to formation of threefold interpenetrated two-dimensional (2D) networks. [PPh4][H2NMe2][(UO2)2(C7)3] (4) and [PPh3Me]2[(UO2)2(C8)3] (5) contain 1D chains, either ladderlike or containing doubly bridged dimers, while [PPh3Me]2[(UO2)2(C9)3]⋅2H2O (6) displays interdigitated, strongly corrugated honeycomb 2D nets. Ladderlike 1D polymers in [Cu(R,S-Me6cyclam)][(UO2)2(C7)2(C2O4)]⋅4H2O (7) are associated into columns by the hydrogen bonded counterions, whereas the [Ni(cyclam)] 2+ moieties are part of the 2D polymeric arrangement in [(UO2)2(C7)2(HC7)2Ni(cyclam)]⋅2H2O (8) due to axial coordination of the nickel(II) centre, hydrogen bonding mediated by water molecules generating a three-dimensional (3D) net. [(UO2)2K2(C7)3(H2O)]⋅0.5H2O (9) contains convoluted uranyl dicarboxylate 2D subunits which generate a 3D framework through 2D  3D parallel polycatenation similar to that previously found in [NH4]2[(UO2)2(C7)3]⋅2H2O; further linking of these subunits is provided by bonding of the potassium cations to carboxylate and uranyl oxido groups. The solid state emission spectra of complexes 1-6 and 9 display maxima positions typical of hexacoordinated uranyl carboxylate complexes, but uranyl luminescence is quenched in 7. A solid-state photoluminescence quantum yield of 11.5% has been measured for complex 1, while those for compounds 3-6 and 9 are in the range of 2.0-3.5%.

In the presence of NH and either PPh or PPhMe cations, 1,3-adamantanediacetic acid (HADA) reacts with uranyl ions under solvo-hydrothermal conditions to give the complexes [NH][PPh][(UO)(ADA)] (1) and [NH][PPhMe][(UO)(ADA)] (2), both of which contain a tetranuclear metallatricycle built from two 2:2 rings including convergent ligands, linked by two additional ligands in an extended conformation defining a third, larger ring. While the ammonium cations are closely associated with the 2:2 rings through triple hydrogen bonding, the large PPh or PPhMe cations are more loosely bound to each of the two faces of the larger ring. In contrast, the complex [HNMe][PPhMe][(UO)(ADA)]·HO (3), in which dimethylammonium replaces ammonium cations, crystallizes as a two-dimensional network with honeycomb {6} topology, albeit with very distorted, elongated hexagonal cells. These and previous results show that both NH and PPh or PPhMe cations are essential to the formation of the metallatricycle. The role of the flexibility imparted to ADA by the acetate arms, in comparison to the more rigid 1,3-adamantanedicarboxylate (ADC), is also discussed. All three complexes are luminescent, with quantum yields of 0.06, 0.06, and 0.09 for 1-3, respectively. The vibronic fine structure apparent on the emission spectra gives peak positions typical of species in which the uranyl ion is chelated by three carboxylate groups.

Fourteen uranyl ion complexes have been obtained from reaction of 1,2-1,3-, or 1,4phenylenediacetic acids (1,2-1,3-, or 1,4-H2PDA) with uranyl nitrate under solvo-hydrothermal conditions and in the presence of diverse additional metal ions and/or N-donor chelating or macrocyclic species. The complexes [UO2(1,2-PDA)(bipy)]CH3CN (1), [UO2(1,2-PDA)(phen)] (2), [UO2(1,3-PDA)(bipy)] (3), and [UO2(1,3-PDA)(phen)] (4), where bipy = 2,2ʹ-bipyridine and phen = 1,10-phenanthroline, crystallize as simple monoperiodic (1D) coordination polymers with slightly variable geometry and mode of association through weak interactions. Complex 5, [H2-2.2.2][(UO2)2(1,2-PDA)3]CH3CN, containing diprotonated [2.2.2]cryptand, crystallizes as a ladderlike 1D polymer, while [NH4]6[Ni(H2O)6]2[(UO2)4(1,2-PDA)6]2[(UO2)4(1,2-PDA)5(H2O)4] (6) contains both a heavily corrugated 1D subunit and a discrete, tetranuclear anionic complex. The three complexes [Cu(bipy)2(NO3)][UO2(1,2-PDA)(NO3)] (7), [Ag(bipy)2][UO2(1,2-PDA)(NO3)] (8), and [Ag(bipy)2][UO2(1,4-PDA)(NO3)] (9) display 1D arrangements close to those in complexes 1-4 due to the presence of terminal nitrate ligands. The heterometallic complex [UO2Pb(1,3-PDA)2(phen)] (10) crystallizes as a diperiodic (2D) network built from 1D ribbons arranged in roof-tile fashion and connected to one another by Pb-O(oxo) links. [(UO2)2Pb2(1,4-PDA)3(HCOO)2(phen)2] (11) displays 1D triple-stranded (UO2)2(1,4-PDA)3 2subunits assembled into a corrugated 2D polymer by double rows of Pb(HCOO)(phen) + bridges. [Zn(bipy)3][(UO2)2(1,2-PDA)(1,4-PDA)2]H2O (12) contains two phenylenediacetate isomers and displays zigzag chains linked to one another by dinuclear rings to give a 2D assembly containing large, elongated decanuclear rings. The two complexes [Cu(R,S-Me6cyclam)][UO2(1,3-PDA)(NO3)]2 (13) and [Ni(cyclam)][(UO2)2(1,3-PDA)3] (14), where cyclam = 1,4,8,11tetraazacyclotetradecane and R,S-Me6cyclam = 7(R),14(S)-5,5,7,12,12,14-hexamethylcyclam, are a 1D polymer analogous to 7-9 and a 2D species containing triple-stranded subunits similar to those in 11, respectively. These and previous results show that the phenylenediacetate ligands have a strong propensity to give 1D polymers with uranyl ion, which can only be partially overcome through the incorporation of additional metal cations, either bound to N-donors to form bulky, structure-directing counterions, or part of heterometallic polymers.