Rational Design and Control of the Dimensions of Channels in Three-Dimensional, Porous Metal-Organic Frameworks Constructed with Predesigned Hexagonal Layers and Pillars

Variation of the Molecular Conformation, Shape, and Cavity Size in Dinuclear Metalla-Macrocycles Containing Hetero-Ditopic Dithiocarbamate-Carboxylate Ligands from a Homologous Series of N-Substituted Amino Acids

A homologous series of dithiocarbamate ligands derived from N-substituted amino acids was reacted with different diorganotin dichlorides to give 18 diorganotin complexes. Spectroscopic and mass spectrometric analysis evidenced the formation of assemblies with six-coordinate tin atoms embedded in skewed-trapezoidal bipyramidal coordination environments of composition C₂SnS₂O₂. Single-crystal X-ray diffraction analysis for three of the compounds revealed a one-dimensional polymeric structure for the complex with the ligand derived from 5-aminopentanoic acid, which through further intermolecular Sn···O interactions generated an overall two-dimensional coordination polymer containing 40-membered hexanuclear tin macrocycles. On the contrary, the ligands derived from 6-aminohexanoic and 8-aminooctanoic acid provided the expected 22- and 26-membered dinuclear macrocyclic structures. Density functional theory calculations for a representative series of macrocyclic complexes of composition [Me₂SnLx]₂ with Lx = ¯S₂CN(Me)-(CH₂)_x-COO¯ (x = 3-12) enabled a detailed analysis of the variations in the molecular conformation, shape, and cavity size of the macrocycles in dependence of the aliphatic spacer. Because of odd-even effects, the difunctional ligands can adopt either a curved or a twisted-pincer shape, while the SnS_xO_4-x (x = 0-4) moieties can act either as linear or angular tectons with varying connectivity angles.

High and selective CO2 uptake in a nitrogen-rich pillar-layered metal organic framework

A pillar-layered cobalt(ii) MOF exhibits high CO₂ uptake and CO₂/N₂ selectivity, fast adsorption kinetics, easy regeneration and excellent stability.

Architectures varying from discrete molecular units to 2-dimensional coordination polymers and photoluminescence behavior of zinc and cadmium comprising an anionic zwitterion of rigid 4,5-dicarboxy-1,3-dimethyl-1H-imidazolium iodide

A rigid ligand, 4,5-dicarboxy-1,3-dimethyl-1H-imidazolium iodide (H₂DDII) and crystallized as zwitterion (1) and employed in the synthesis of anionic zwitterion complexes or coordination polymers (CPs)2–6of Zn(ii) and Cd(ii).

Multifunctional MOFs through CO2fixation: a metamagnetic kagome lattice with uniaxial zero thermal expansion and reversible guest sorption

The properties of atmospheric CO₂fixation, metamagnetism, reversible guest adsorption and zero thermal expansion have been combined in a single robust MOF, [Cu₃(bpac)₃(CO₃)₂](ClO₄)₂·H₂O (1·H₂O).

Different interpenetrated coordination polymers based on flexible dicarboxylate ligands: topological diversity and magnetism

This work evidently indicates that the effect of the secondary ligands, molar ratios and geometric preferences of the metal centers are critical on the resulting entangled motifs.

Poly[[[diaqua-sodium]-μ(3)-5-carb-oxy-2-ethyl-1H-imidazole-4-carboxyl-ato-κN,O:O:O] monohydrate]

In the title complex, {[Na(C₇H₇N₂O₄)(H₂O)₂]·H₂O}_n, the Na^I atom exhibits a distorted octa­hedral geometry and is six-coordinated in an NO₅ environment. The equatorial plane is defined by three O atoms and one N atom from two distinct 5-carb­oxy-2-ethyl-1H-imidazole-4-carboxyl­ate (H₂EIDC) ligands and one coordinated water mol­ecule, and the apical sites are occupied by one carboxyl O atom from one H₂EIDC ligand and one O atom from the other coordinated water mol­ecule. The Na^I atoms are linked by H₂EIDC ligands, generating an infinite double chain along the a axis. These chains are further connected via O—H⋯O and N—H⋯O hydrogen bonds into a three-dimensional supra­molecular network.

Diaqua-bis-(5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ato-κN,O)cadmium(II) 3.5-hydrate

In the title complex, [Cd(C(8)H(9)N(2)O(4))(2)(H(2)O)(2)]·3.5H(2)O, the Cd(II) is coordinated by two water mol-ecules and N,O-chelated by two 5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ate anions in a distorted octa-hedral geometry. The two imidazole rings are oriented to each other with a dihedral angle of 75.1 (2)°. Strong O-H⋯O hydrogen bonds between protonated and deprotonated carboxyl-ate groups occur in the mol-ecular structure. In the crystal structure extensive O-H⋯O and N-H⋯O hydrogen bonds help to stabilize the three-dimensional supra-molecular framework. The propyl groups of anions are disordered over two sites with refined occupancies of 0.768 (6):0.232 (6) and 0.642 (8):0.358 (8).

Diaqua-bis-(5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ato-κN,O)zinc(II) 3.5-hydrate

In the title complex, [Zn(C(8)H(9)N(2)O(4))(2)(H(2)O)(2)]·3.5H(2)O, the Zn(II) ion is coordinated by two N,O-bidentate H(2)pimda ligands (H(3)pimda = 2-propyl-1H-imidazole-4,5-dicarb-oxy-lic acid) and two water mol-ecules in a distorted octa-hedral environment. In the crystal structure, extensive inter-molecular O-H⋯O and N-H⋯O hydrogen bonds stabilize the three-dimensional supra-molecular network. Intra-molecular O-H⋯O hydrogen bonds between the carboxyl groups are also observed. The propyl groups of the two H(2)pimda ligands are disordered each over two sites, with occupancy factors of 0.752 (5):0.248 (5) and 0.519 (7):0.481 (7). One of the water mol-ecules is half-occupied.

Diaqua-bis-(4-carb-oxy-2-propyl-1H-imidazole-5-carboxyl-ato-κN,O)copper(II) N,N-dimethyl-formamide disolvate

In the title complex, [Cu(C(8)H(9)N(2)O(4))(2)(H(2)O)(2)]·2C(3)H(7)NO, the Cu(II) ion, lying on an inversion center, is six-coordinated in a slightly distorted octa-hedral geometry. Two N atoms and two O atoms from two H(2)pimda (H(3)pimda is 2-propyl-1H-4,5-dicarb-oxy-lic acid) ligands are in the equatorial plane. The axial positions are occupied by two O atoms from two water mol-ecules. A two-dimensional supra-molecular network parallel to (001) is constructed by N-H⋯O and O-H⋯O hydrogen bonds. An intra-molecular O-H⋯O hydrogen bond is also observed.

Diaqua-bis-(5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ato-κN,O)nickel(II) tetra-hydrate

In the title complex, [Ni(C₈H₉N₂O₄)₂(H₂O)₂]·4H₂O, the Ni^II ion is coordinated in a slightly distorted octa­hedral environment formed by two bis-chelating H₂pimda (H₃pimda is 2-propyl-1H-4,5-dicarb­oxy­lic acid) ligands and two coordinated water mol­ecules. In the crystal structure, a three-dimensional framework is formed by inter­molecular O—H⋯O and N—H⋯O hydrogen bonds involving the solvent water mol­ecules, coordinated water mol­ecules, carboxyl­ate O atoms and the protonated N atoms of the H₂pimda ligands. The propyl groups of each H₂pimda ligand are disordered over two sets of sites with refined occupancies of 0.50 (2):0.50 (2) and 0.762 (11):0.238 (11). In one water solvent mol­ecule, one of the H atoms was refined as disordered over two sites of equal occupancy.

Supramolecular coordination assemblies constructed from multifunctional azole-containing carboxylic acids

This paper provides a brief review of recent progress in the field of metal coordination polymers assembled from azole-containing carboxylic acids and gives a diagrammatic summary of the diversity of topological structures in the resulting infinite metal-organic coordination networks (MOCNs). Azole-containing carboxylic acids are a favorable kind of multifunctional ligand to construct various metal complexes with isolated complexes and one, two and three dimensional structures, whose isolated complexes are not the focus of this review. An insight into the topology patterns of the infinite coordination polymers is provided. Analyzed topologies are compared with documented topologies and catalogued by the nature of nodes and connectivity pattern. New topologies which are not available from current topology databases are described and demonstrated graphically.