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A chiral, octahedral M 12 L 12 cage, which is charge neutral and contains an internal void of about 2000 Å 3 , is reported. The cage was synthesised as an enantiopure complex by virtue of amino-acid-based dicarboxylate ligands, which assemble around copper paddlewheels at the vertices of the octahedron. The cage persists in solution with retention of the fluorescence properties of the parent acid. The solid-state structure contains large pores both within and between the cages, and displays permanent porosity for the sorption of gases with retention of crystallinity. Initial tests show some enantioselectivity of the cage towards guests in solution., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Reaction of the chloranilate dianion with Y(NO 3 ) 3 in the presence of Et 4 N + in the appropriate proportions results in the formation of (Et 4 N)[Y(can) 2 ], which consists of anionic square-grid coordination polymer sheets with interleaved layers of counter-cations. These counter-cations, which serve as squat pillars between [Y(can) 2 ] sheets, lead to alignment of the square grid sheets and the subsequent generation of square channels running perpendicular to the sheets. The crystals are found to be porous and retain crystallinity following cycles of adsorption and desorption. This compound exhibits a high affinity for volatile guest molecules, which could be identified within the framework by crystallographic methods. In situ neutron powder diffraction indicates a size-shape complementarity leading to a strong interaction between host and guest for CO 2 and CH 4 . Single-crystal X-ray diffraction experiments indicate significant interactions between the host framework and discrete I 2 or Br 2 molecules. A series of isostructural compounds (cat)[M III (X-an) 2 ] with M=Sc, Gd, Tb, Dy, Ho, Er, Yb, Lu, Bi or In, cat=Et 4 N, Me 4 N and X-an=chloranilate, bromanilate or cyanochloranilate bridging ligands have been generated. The magnetic properties of representative examples (Et 4 N)[Gd(can) 2 ] and (Et 4 N)[Dy(can) 2 ] are reported with normal DC susceptibility but unusual AC susceptibility data noted for (Et 4 N)[Gd(can) 2 ]., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The need for effective CO 2 capture systems remains high, and due to their tunability, metallosupramolecular architectures are an attractive option for gas sorption. While the use of extended metal organic frameworks for gas adsorption has been extensively explored, the exploitation of discrete metallocage architectures to bind gases remains in its infancy. Herein the solid state gas adsorption properties of a series of [Pd 2 (L) 4 ] 4+ lantern shaped coordination cages (L = variants of 2,6-bis(pyridin-3-ylethynyl)pyridine), which had solvent accessible internal cavities suitable for gas binding, have been investigated. The cages showed little interaction with dinitrogen gas but were able to take up CO 2 . The best performing cage reversibly sorbed 1.4 mol CO 2 per mol cage at 298 K, and 2.3 mol CO 2 per mol cage at 258 K (1 bar). The enthalpy of binding was calculated to be 25-35 kJ mol -1 , across the number of equivalents bound, while DFT calculations on the CO 2 binding in the cage gave ΔE for the cage-CO 2 interaction of 23-28 kJ mol -1 , across the same range. DFT modelling suggested that the binding mode is a hydrogen bond between the carbonyl oxygen of CO 2 and the internally directed hydrogen atoms of the cage., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The uptake of inhalation anesthetics by three topologically identical frameworks is described. The 3D network materials, which possess square channels of different dimensions, are formed from the relatively simple combination of Zn II centres and dianionic ligands that contain a phenolate and a carboxylate group at opposite ends. All three framework materials are able to adsorb N 2 O, Xe and isoflurane. Whereas the framework with the widest channels is able to adsorb large quantities of the various guests from the gas phase, the frameworks with the narrower channels have superior binding enthalpies and exhibit higher levels of retention. The use of ligands in which substituents are bound to the aromatic rings of the bridging ligands offers great scope for tuning the adsorption properties of the framework materials., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The structure of Li(inox)⋅2/3 DMF (inox(-) =the N-oxide of the isonicotinate anion) consists of a 3D framework with solvent-filled, square cross-section channels of approximate dimensions 5.5×5.5 Å. Unfortunately, the Li(inox) framework is unstable upon removal of DMF from the channels. When the structurally related 4-hydroxybenzoic acid (H2 hba) was used in place of Hinox, and Zn(2+) in place of the Li(+) , a structurally similar but more robust network, Zn(hba), was obtained; the isostructural compound, Co(hba), may also be prepared. Longer ligands with phenolate and carboxylate functional groups at opposite ends, such as the dianions of 4-coumaric acid (H2 cma) and 4'-hydroxy-4-biphenylcarboxylic acid (H2 hbpc), in combination with Zn(2+) yield Zn(cma) and Zn(hbpc) frameworks, respectively, with the same PtS topology but with larger channels. The coordination polymers remain intact after desolvation and exhibit microporosity, showing the ability to sorb significant quantities of CO2 , CH4 , and H2 ., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)