A novel three-dimensional Cd^II metal–organic framework based on [Cd₆(malonate)₆] metallomacrocycles with zeolite SOD (sodalite) topology: poly[ammine-μ₃-malonato-cadmium(II)]

A novel Cd^II metal–organic framework, [Cd(C₃H₂O₄)(NH₃)]_n, was synthesized by liquid diffusion conducted in the presence of ammonia. The Cd^II atom has seven-coordinate O₆N penta­gonal–bipyramidal geometry. Six Cd^II centers are joined by six malonate ligands to form an S₆-symmetric [Cd₆(malon­ate)₆] metallomacrocycle, which is further extended through a side-on chelating malonate ligand to form a three-dimensional network. Topologically, each Cd^II center is connected to four others to yield an infinite three-periodic four-coordinated SOD (sodalite) network with point symbol {4²·6⁴}. The overall network structure in the crystal is maintained and stabilized by the presence of N—H...O hydrogen bonds.

A one-dimensional coordination polymer based on a di-Schiff base supported trinuclear Cu^II subunit

A novel one-dimensional Cu^II coordination polymer, catena-poly[bis­(μ₄-3-{[2-(3-hydroxy-2-oxido­benzyl­idene)­hydrazinylidene]­methyl}­benzene-1,2-diolato)­dimethanol­tricopper(II)], [Cu₃(C₁₄H₁₀N₂O₄)₂(CH₃OH)₂]_n, (I), was constructed with a di-Schiff base supported centrosymmetric trinuclear Cu^II subunit. In the subunit, two peripheral symmetry-related Cu^II cations have square-pyramidal CuNO₄ geometry and the central third Cu^II cation lies on an inversion centre with octahedral CuN₂O₄ geometry. In (I), each partially deproton­ated di-Schiff base 3-{[2-(3-hydroxy-2-oxido­benzyl­idene)­hy­dra­zinyl­idene]­methyl}­benzene-1,2-diolate ligand (Hbcaz³⁻) acts as a hepta­dentate ligand to bind the Cu^II centres into chains along the a axis. A centrosymmetric Cu₂O₂ unit containing an asymmetrically bridging O atom, being axial at one Cu atom and equatorial at the other Cu atom, links the trinuclear Cu^II subunit into a one-dimensional chain, which is reinforced by intra­molecular phenol–methanol O—H...O and methanol–phenolate O—H...O hydrogen bonds. Interchain π–π stacking interactions between pyrocatechol units, with a distance of 3.5251 (18) Å, contribute to the stability of the crystal packing.

A novel one-dimensional silver cylinder stabilized by mixed 2-mercaptobenzoic acid and ethylene­diamine ligands

A novel infinite one-dimensional silver cylinder, namely poly[[mu]-ethyl­enedi­am­ine-[mu]₅-(2-sulfanidylbenzoato)-[mu]₄-(2-sul­fanidylbenzoato)-tetra­silver(I)], [Ag₄(C₇H₄O₂S)₂(C₂H₈N₂)]_n, has been synthesized by one-pot reaction of equivalent molar silver nitrate and 2-mercaptobenzoic acid (H₂mba) in the presence of ethyl­enediamine (eda). One Ag atom is located in an AgS₂NO four-coordinated tetra­hedral geometry, two other Ag atoms are in an AgS₂O three-coordinated T-shaped geometry and the fourth Ag atom is in an AgSNO coordination environment. The two mba ligands show two different binding modes. The [mu]₂-N:N'-eda ligand, acting as a bridge, combines with mba ligands to extend the Ag^I ions into a one-dimensional silver cylinder incorporating abundant Ag...Ag inter­actions ranging from 2.9298 (11) to 3.2165 (13) Å. Inter­chain N-H...O hydrogen bonds extend the one-dimensional cylinder into an undulating two-dimensional sheet, which is further packed into a three-dimensional supra­molecular framework by van der Waals inter­actions; no [pi]-[pi] inter­actions were observed in the crystal structure.