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The solvothermal reaction of In(iii) and 1,2,4,5-benzeneteracarboxylic acid with the presence of piperazine leads to the generation of a novel 3D chiral porous coordination polymer with PtS topological net. Interestingly, the resulting crystals were not a racemic mixture but enantiomeric excess, which was confirmed by the measurement of optical rotation of bulk samples using solid vibrational circular dichroism (VCD) spectra and the solid circular dichroism (CD) spectra based on large crystals from one crystallization. High-pressure CO2and CH4adsorption measurement at 298 K reveals that activated 1can absorb 45.8 cm3(STP)/g CO2at 22 atm and 22.5 cm3(STP)/g CH4at 25 atm. [ABSTRACT FROM AUTHOR]

A one-dimensional ribbon copper(II) complex, {CuII3(L)2(OH)2(NO3)2(H2O)4}n (1, HL=1-methyl-2-(3H-[1-3]triazol-4-yl)-1H-benzimidazole), has been hydrothermally synthesized from in situ generated HL at 160°C. Its structure is very unusual that all ligands and Cu(II) ion are distributed in the same horizontal plane in each chain. Two ligands chelate and bridge two Cu(II) ions to form a planar metalloligand which is then connected to each other through coordination to another Cu(II) to give the 2+1 infinite chain structure. Axial coordination sites of the Cu(II) are taken up by nitrate and water. Hydrogen bonding and π-π stacking interactions between chains intensify the stability of 3D supramolecular architecture. This particular structure is the result of a cooperative effect associated with the Jahn-Teller distortion of the copper(II) ion, the hydrogen bonding and π-π stacking interactions. Its magnetic properties indicate antiferromagnetic interactions between copper(II) within the chain. [ABSTRACT FROM AUTHOR]

Abstract: A chiral cluster-based 3D coordination polymer [Co2(ca)(ina)2(H2O)] n (1, ca= d-(+)-camphorate, ina=isonicotinate), containing mixed geometries cobalt(II) dimers as subunit, featuring unique rugate [Co2(ina)2] n 2 n + 2D layers pillared by the ca ligands has been studied. The bridge modes and their intermolecular interactions of the mixed rigid planar ina and flexible bulky ca ligands display an interesting example of shape recognition in packing style of 3D frameworks. The bulky antiferromagnetic behavior of 1, mainly arises from the cooperative magnetic effect of the interdimers arrangement in the chiral 3D network based on the nature of the exchange modes of mixed multi-carboxylate bridges within the mixed geometric Co(II) dimer. [Copyright &y& Elsevier]

This review focuses on a particular class of porous coordination polymers (PCPs) called metal cluster-based PCPs, which are constructed by linking versatile polynuclear clusters as secondary building units via organic linkers. These types of PCPs provide a unique platform for systematically studying the correlations among structure–property relationships and for developing new functional PCP materials with improved properties due to their various advantages, such as their diverse components, stable frameworks, highly predictable topologies, controllable structural flexibility, and various modifiable functionalities. In this review, we highlight and discuss selected examples of cluster-based PCPs, the functionalities of which benefit from either the clusters themselves or their cooperation with linkers, such as gas adsorption, heterogeneous catalysis, magnetism, flexibility, and luminescent sensing, as well as modulations of these functionalities via post-synthetic modifications of the cluster building units. [ABSTRACT FROM AUTHOR]

Abstract: A new 2D coordination polymer with the formula [Co4(μ3-OH)2(H2nip-2H)2(H2nip-H)2(bpe)2] n (1) (H2nip=5-nitro-isophthalic acid, bpe= trans-1,2-bis(4-pyridyl)ethylene), has been hydrothermally synthesized and structurally characterized. The structure of 1 is built around uncommon, rhombic {Co4} clusters with double T d and double O h Co(II) geometries, which are extended into 2D network by the rigid deprotonated H2nip and bpe bridges. Magnetic property study indicates there is weak antiferromagnetic coupling interaction between Co(II) ions, which mainly arises from the antiferromagnetic coupling interaction in the tetramer, based on the nature of the μ3-hydroxyl group and syn–syn carboxylate-bridged modes. [Copyright &y& Elsevier]

Abstract: The hydrothermal preparation via variations of dicarboxylate ligands (terephthalate (bdc) or d(+)-camphorate (ca)) with lead nitrate exhibits two new 3D coordination polymer. In complex 1 [Pb(bdc)2] n , linear rigid bdc ligands exhibit unique (μ 5-κO-μ 2:κO′:κO′′,O′′′:κO′′-μ 2) coordination mode. The carboxyl groups of bdc link adjacent lead(II) atoms to form a 2D infinite undulated [Pb(CO2)2] n layer, and further linked via the benzene ring of bdc to form a 3D pillared-layer compact framework. In contrast, complex 2 [Pb(ca)2·H2O] n exhibits a rod packing 3D sra (Al net in SrAl2) network with the combination of [Pb(CO2)2·H2O] n rods through (μ 4-κO,O′:κO′′,O′′′:κO′′-μ 2:κO′′′-μ 2) coordination mode of the bulky chiral ca linkers. Both in 1 and 2, the arrangement of donor atoms suggest the coordination around the lead(II) atoms is hemi-directed. The different steric hindrance of two bridged ligands, and lone pair electrons effect of lead(II) ion cooperatively influence bdc and ca displaying in diverse connecting modes and further result in different packing styles of two 3D motif. Two complexes exhibit an excellent thermal stability with the tolerate temperature ca. 410°C for 1 and 390°C for 2, respectively, attributed to the presence of abundant coordination bonds of dicarboxylate ligands and the infinite rod-shaped or layered building blocks in above 3D compact frameworks. [Copyright &y& Elsevier]

A cadmium (II) coordination polymer, namely {[Cd5(Ln)6Cl4]·2H2O}n (1, HLn =1-methyl-2-(3H-[1–3]triazol-4-yl)-1H-benzoimidazole), has been constructed from in situ generated HLn under hydrothermal condition. The unsuccessful synthesis of 1 under similar synthesis condition using HLn as reactant suggests the in situ reaction is crucial for the assembly of the compound. Crystallography study reveals that 1 processes layer structure in which chains of [Cd3(Ln)4Cl4]2− were connected by a pair of Cd ions. These layers further stack in an AAA model to form a 3D supramolecular framework and hydrogen bonding as well as π–π interaction were formed between adjacent layers to stabilize the framework. TGA indicates that 1 is highly thermally stable up to about 380°C. The luminescence of 1 in the solid state which may be assigned to intraligand transition shows a blue shift of 16nm compared to that of HLn·HCl. [ABSTRACT FROM AUTHOR]