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There is a concerted attempt to develop self‐assembled metallo‐cages of greater structural complexity, and heteroleptic PdII cages are emerging as prime candidates in these efforts. Most of these are dinuclear: few examples of higher nuclearity have been reported. We demonstrate here a robust method for the formation of tripalladium(II) cages from the 2 : 3 : 3 combination of a tritopic ligand, PdII, and a selection of ditopic ligands of the correct size and geometry. [ABSTRACT FROM AUTHOR]

A systematic expansion of the well-known non-interpenetrated and robust MOF-11 was accomplished through a rediscovery of the ligand tetrakis(4-carboxyphenyl)adamantane (L). The combination of a rigid tetrahedral L and copper(ii) paddle-wheel secondary building unit (SBU) resulted in a stable non-interpenetrated metal–organic framework, UOF-1 (UOF = University of Otago framework), with the predicted PtS topology. This MOF exhibits permanent porosity, as established by X-ray diffraction (XRD) and gas adsorption studies. This low-density open framework possesses one open-metal site per Cu(ii) cation which could be accessed by employing appropriate activation techniques such as the use of supercritical CO2 (s-CO2) or dry CH2Cl2. CO2 gas displayed higher affinity towards activated UOF-1 than CH4 and N2 gases at room temperature and low pressure. UOF-1 displayed excellent selectivity for CO2 over N2 of 52 : 1 at practical operating conditions of 15 : 85 CO2 : N2 mixture at 273 K and 1 bar. [ABSTRACT FROM AUTHOR]

he design and synthesis of a Lonsdaleite (lon) network is an attractive and challenging supramolecular target. Our reticular synthesis strategy of slow diffusion of solutions of a simple rigid tetrahedral ligand and a Ag(I) metal ion, at room temperature and atmospheric pressure, resulted in both lon-MOFs and diamondoid (dia-MOFs) and associated 2D honeycomb networks. Solvent appeared to play a key role in templating the formation of these related networks. Nanoindentation studies show that a dia-MOF was 42% harder than a lon-MOF counterpart. The lon-MOFs were thermally stable and retained integrity until 370 °C while dia-MOFs exhibited stepwise collapse after initial loss of solvents. As lon networks are often only qualitatively identified, Cremer-Pople ring puckering analysis was used to quantify the degree of distortion in the lon and related 4-connected 66 networks. [ABSTRACT FROM AUTHOR]

The synthesis and characterisation by IR spectroscopy and elemental analysis of ten new Ag(I)-L complexes are described. Of these complexes, nine are characterised by single crystal X-ray diffraction: {[Ag(L)](CF3SO3)·½H2O}∞ (1), {[Ag(L)](ClO4)·1/2H2;)∞ (2), {[Ag2(L)2(CH3CN)](ClC4)2·H2O)∞ (3), {[Ag2(L)2(CH3CN)2](ClO4)2·CH3CN)∞ (4), {[Ag2(L)2(CH3CN)2](PF6)2·2CH3CN)∞ (5), {[Ag(L)2](CF3SO3)4/2H2OL (6), {[Ag(L)2](BF4)∞(7), {[Ag(L)2](PF6))∞ (8) and {[Ag(L)2](PF6)·2CH3CN)∞ (9). The primary structures of 1-6 were meso-helical one-dimensional (1D) polymers, while 7 was a helical 1D polymer and 8 and 9 were (4,4) networks. Complexes 1-5 possessed 1:1 metal-to-ligand (M: L) ratios, while complexes 6-9 possessed 1:2 M: L ratios. The meso-helical chains of complexes 1 and 2 were di-μ-bridged at the Ag(I) nodes by the counteranions CF3SC>3- and CIO4-, respectively, while the meso-helical chains of complexes 3-5 were di-μ-bridged at the Ag(I) nodes by the CH3CN molecules. The effect of counteranions and solvent molecules on delicate anion-Ag, π-π-stacking and argentophilic interactions was studied through complexes 1-5. The 1D chains of complexes 6 and 7 possessed monodentate L ligand side arms. The uncoordinated N-donors of these side arms were inclined towards the Ag(I) centre of the adjacent chains and demonstrated narrower Ag-Npy-Cg(pyridyl) angles. In the case of complexes 8 and 9, wider Ag-Npy-Cg(pyridyl) angles and stronger N⋯Ag interactions resulted in (4,4) nets. The effects of the size and the nature of the counteranions on the topology were studied through complexes 6-9. [ABSTRACT FROM AUTHOR]