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The title coordination polymer with the 4-methyl-N-(pyridin-2-yl­methyl­idene)aniline Schiff base ligand (L, C13H12N2), [Cd2Cl4(C13H12N2)]n (1), exhibits a columnar structure extending parallel to [100]. The columns are aligned in parallel and are decorated with chelating L ligands on both sides. They are elongated into a supra­molecular sheet extending parallel to (01⥘) through π–π stacking inter­actions involving L ligands of neighbouring columns. Adjacent sheets are packed into the tri-periodic supra­molecular network through weak C—H⋯Cl hydrogen-bonding inter­actions that involve the phenyl CH groups and chlorido ligands. The thermal stability and photoluminescent properties of (1) have also been examined. [ABSTRACT FROM AUTHOR]

Reacting trimesic acid (H3TMA, C9H6O6) with CaCl2 and MCl2 at 110 °C under hydrothermal conditions gave the isostructural heterobimetallic coordination polymers (CPs) catena‐poly[[tetraaquazinc(II)]‐μ‐5‐carboxybenzene‐1,3‐dicarboxylato‐[tetraaquacalcium(II)]‐μ‐5‐carboxybenzene‐1,3‐dicarboxylato], [CaZn(HTMA)2(H2O)8]n, 1, and catena‐poly[[tetraaquacobalt(II)]‐μ‐5‐carboxybenzene‐1,3‐dicarboxylato‐[tetraaquacalcium(II)]‐μ‐5‐carboxybenzene‐1,3‐dicarboxylato], [CaCo(HTMA)2(H2O)8]n, 2. Compounds 1 and 2 crystallize in the monoclinic space group C2/c. The solid‐state structures consist of eight‐coordinate CaII ions and six‐coordinate MII ions. These ions are connected by a doubly deprotonated HTMA2− ligand to create a one‐dimensional (1D) zigzag chain. Poly[[decaaquabis(μ3‐benzene‐1,3,5‐tricarboxylato)calcium(II)dizinc(II)] dihydrate], {[CaZn2(TMA)2(H2O)10]·2H2O}n, 3, was found incidentally as a minor by‐product during the synthesis of 1 at a temperature of 140 °C. It forms crystals in the orthorhombic space group Ccce. The structure of 3 consists of a two‐dimensional (2D) layer composed of [Zn(TMA)] chains that are interconnected by CaII ions. The presence of aromatic carboxylic acid ligands and water molecules, which can form numerous hydrogen bonds and π–π interactions, increases the stability of the three‐dimensional (3D) supramolecular architecture of these CPs. Compounds 1 and 2 exhibit thermal stability up to 420 °C, as indicated by the thermogravimetric analysis (TGA) curves. The powder X‐ray diffraction (PXRD) data reveal the formation of unidentified phases in methanol and dimethyl sulfoxide, while 1 exhibits chemical stability in a wide range of solvents. The luminescence properties of 1 dispersed in various low molecular weight organic solvents was also examined. The results demonstrate excellent selectivity, sensitivity and recyclability for detecting acetone molecules in aqueous media. Additionally, a possible sensing mechanism is also outlined. [ABSTRACT FROM AUTHOR]

The title coordination polymer with the 4-methyl-N-(pyridin-2-yl-methyl-idene)aniline Schiff base ligand (L, C13H12N2), [Cd2Cl4(C13H12N2)] n (1), exhibits a columnar structure extending parallel to [100]. The columns are aligned in parallel and are decorated with chelating L ligands on both sides. They are elongated into a supra-molecular sheet extending parallel to (01) through π-π stacking inter-actions involving L ligands of neighbouring columns. Adjacent sheets are packed into the tri-periodic supra-molecular network through weak C-H⋯Cl hydrogen-bonding inter-actions that involve the phenyl CH groups and chlorido ligands. The thermal stability and photoluminescent properties of (1) have also been examined. [ABSTRACT FROM AUTHOR]

In the title lanthanide(III) compound, [Tb(NO3)2(C2H6N2O)3]NO3, the asym­metric unit contains one Tb3+ ion, three acetohydrazide (C2H6N2O) ligands, two coordinated nitrate anions, and an isolated nitrate anion. The Tb3+ ion is in a ninefold coordinated distorted tricapped trigonal–prismatic geometry formed by three oxygen atoms and three nitro­gen atoms from three different acetohydrazide ligands and three oxygen atoms from two nitrate anions. In the crystal, the complex mol­ecules and the non-coordinated nitrate anions are assembled into a three-dimensional supra­molecular architecture through extensive N—HO hydrogen-bonding inter­actions between the amine NH groups of the acetohydrazide ligands and the nitrate oxygen atoms. Hirshfeld surface analysis was performed to aid in the visualization of inter­mol­ecular contacts. [ABSTRACT FROM AUTHOR]

Four isostructural dinuclear M2L2 mesocates of the general formula [M2(NCS)4(L)2]·4.5MeOH (1M; M = Mn, Fe, Co, Zn) were constructed by using the coordination-driven self-assembly of the [M(NCS)2] precursor and the flexible bis-bidentate pyridylimine Schiff base ligand L (L = 4,4′-(1,4-phenylenebis(oxy))bis(N-(pyridin-2-ylmethylene)aniline). The centrosymmetric M2L2 mesocate forms through the side-by-side coordination of two L ligands to a pair of M(II) ions. The mesocates exhibit a reversible temperature induced desolvation–solvation behavior without losing their structural integrity. The activated 1Co, as the representative M2L2 mesocate, shows an exceptionally high MeOH vapour uptake capacity of 481.9 cm3 g−1 (68.8 wt%) at STP with good recyclability. Notably, it also exhibits CO2 adsorption with an uptake capacity of 20.2 cm3 g−1 (3.6 wt%) at room temperature and 1 bar. [ABSTRACT FROM AUTHOR]

The title compound, C8H4Br2O4.C2H6O2, crystallizes with one-half of a 2,5-dibromoterephthalic acid (H2Br2tp) molecule and one-half of an ethylene glycol (EG) molecule in the the asymmetric unit. The whole molecules are generated by application of inversion symmetry. The H2Br2tp molecule is not planar, with the dibromobenzene ring system inclined by a dihedral angle of 18.62 (3)° to the carboxylic group. In the crystal, the H2Br2tp and EG molecules are linked into sheets propagating parallel to (101) through O--H···O hydrogen bonds, thereby forming R44(12) and R44(28) graph-set motifs. Br···O and weak π-π stacking interactions are also observed. Hirshfeld surface analysis was used to confirm the existence of these interactions. [ABSTRACT FROM AUTHOR]

Fourteen three-dimensional (3D) lanthanide coordination polymers (CPs) with dicarboxylate mixed ligands, [Ln(fum)1.5(H2O)2]·0.5(H2bdc)·H2O (Ln = Sm (1), Tb (2)), [Ln2(fum)2(bdc)(H2O)4]·2H2O (Ln = Sm (3), Eu (4), Tb (5), Er (6)), [Ln(fum)0.5(bdc)] (Ln = Sm (7), Eu (8), Tb (9), Er (10)), and [Ln2(bdc)2(ox)(H2O)4]·0.7H2O (Ln = Sm (11), Gd (12), Tb (13), Dy (14)), have been synthesized hydrothermally from the self-assembly of lanthanide(iii) ions (Ln3+), fumaric acid (H2fum), and terephthalic acid (H2bdc) in the presence of potassium hydroxide at different temperatures. The compounds fall into four classes. Compounds 1 and 2 were isolated from hydrothermal reactions performed at a relatively low temperature of 100 °C and found to crystallize in the triclinic space group P1̅. The 3D framework is assembled from 2D layers of [Ln(fum)(H2O)2] units pillared by the chelating fum ligands and has 1D rhombic channels templated by H2bdc and lattice H2O molecules. The framework presents a binodal (4,5)-connected tcs topology with the point symbol (44·62)(44·66). Raising the reaction temperature to 140 °C resulted in the formation of compounds 3–6. These materials crystallize in the monoclinic system with the polar space group P21 and feature a 3D network constructed from dinuclear {Ln2(OCO)6(H2O)4} units interlinked by fum and bdc ligands, showing a uninodal 6-connected two-fold interpenetrated pcu topology. The small channels of the framework are occupied by lattice H2O molecules. Further increase of the reaction temperature to 160 °C gave rise to the formation of compounds 7–10, crystallizing in the orthorhombic space group Pbca. The 3D framework is generated from 2D corrugated sheets of [Ln(fum)]2+ bound by bdc ligands and contains no intercalated H2O molecules in the lattice. The framework possesses a trinodal (4,6,7)-connected net with the point symbol (42·64)2(46·68·8)(412·69)2. Finally, compounds 11–14 contained an in situ generated oxalate (ox) ligand formed under hydrothermal conditions conducted at a high reaction temperature of 180 °C. These compounds crystallize in the monoclinic space group P21/c and possess a 3D open framework consisting of a dinuclear [Ln2(ox)(H2O)4]2+ unit linked by bridging bdc ligands and has small void channels occupied by lattice H2O molecules. The frameworks were topologically simplified as a binodal (4,5)-connected tcj/hc net with a total point symbol of (42·52·72)(42·53·75). In the solid state at room temperature, the Tb (2, 5, 9, and 13) and Eu (4 and 8) compounds emit green and red light, respectively. [ABSTRACT FROM AUTHOR]

The first benzohydrazide complex of a lanthanide is reported. In the title compound, [Sm(C8H4O4)(C7H8N2O)3(H2O)2]NO3, systematic name diaquatris( benzohydrazide-κ²N,O)(isophthalato-κO)samarium(III) nitrate, the SmIII ion is nine-coordinated in a distorted tricapped trigonal–prismatic geometry by three oxygen atoms and three nitrogen atoms from three benzhydrazide (bzz) ligands, one oxygen atom from the isophthalate (itp2-) ligand, and two oxygen atoms from coordinated water molecules. The nitrate group is disordered over two sets of sites with occupancy factors of 0.310 (17) and 0.690 (17). In the crystal, adjacent molecules are linked into chains via pairs of O—H···O and N—H···O hydrogen bonds between the carboxylate acceptor and the coordinated water and amine NH2 donors. Molecules are further stacked by π-π interactions involving the benzene ring of the itp2- ligands, forming double chains that extend in the b-axis direction. These double chains are further linked into a three-dimensional supramolecular network via hydrogen bonds (O— H···O, N—H···O and C—H···O) between the complex molecule and the nitrate groups along with C—H···π and π-π interactions involving the benzene rings of the bzz and itp2- ligands. [ABSTRACT FROM AUTHOR]

Two new lanthanide-based coordination polymers, [Sm2(bzz)(ben)6(H2O)3]·0.5H2O (1) and [Eu(bbz)(ben)3] (2), were synthesized and characterized. The described products were formed from in situ-generated benzoate (ben) and N'-benzoylbenzohydrazide (bbz) ligands, which were the products of transformation of originally added benzhydrazide (bzz) under hydrothermal conditions. Compound 1 exhibits a one-dimensional (1D) double-chain structure built up from the connection of the central Sm3+ ions with a mixture of bzz and ben ligands. On the other hand, 2 features a 3D network with a 4-connected (66) dia topology constructed from dinuclear [Eu2(ben)6] secondary building units and bbz linkers. High-pressure CO2 sorption studies of activated 1 show that maximum uptake increases to exceptionally high values of 376.7 cm3 g−1 (42.5 wt%) under a pressure of 50 bar at 298 K with good recyclability. Meanwhile, 2 shows a typical red emission in the solid state at room temperature with the decay lifetime of 1.2 ms. [ABSTRACT FROM AUTHOR]

Crystals CdSO4(H2O) are hydrothermally grown from an aqueous solution of equimolar amounts of CdSO4·8/3H2O and 3,6-di-2-pyridyl-1,2,4,5-tetrazine (autoclave, 356 K, 5 d). [ABSTRACT FROM AUTHOR]

A highly regioselective divergent approach is reported for the synthesis of both indeno[2,1- c ]pyran-3-one and 1-oxazolonylisobenzofuran derivatives using the Erlenmeyer-Plöchl azlactone (EPA) reaction. This approach involves the synthesis of o -(2-acyl-1-ethynyl)benzaldehydes, which reacted with various amino acids. Reaction with N -acylglycines resulted in the formation of indeno[2,1- c ]pyran-3-ones, involving the sequential formation of two C-C bonds and two C-O bonds. Conversely, when the same conditions were applied to free amino acids, 1-oxazolonylisobenzofurans were obtained. This reaction involved the formation of a C-C bond between oxazolone and o -(2-acyl-1-ethynyl)benzaldehyde, followed by the formation of a C-O bond through a selective 5 -exo-dig cyclization., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Four isostructural dinuclear M2L2 mesocates of the general formula [M2(NCS)4(L)2]·4.5MeOH (1M; M = Mn, Fe, Co, Zn) were constructed by using the coordination-driven self-assembly of the [M(NCS)2] precursor and the flexible bis-bidentate pyridylimine Schiff base ligand L (L = 4,4'-(1,4-phenylenebis(oxy))bis(N-(pyridin-2-ylmethylene)aniline). The centrosymmetric M2L2 mesocate forms through the side-by-side coordination of two L ligands to a pair of M(ii) ions. The mesocates exhibit a reversible temperature induced desolvation-solvation behavior without losing their structural integrity. The activated 1Co, as the representative M2L2 mesocate, shows an exceptionally high MeOH vapour uptake capacity of 481.9 cm3 g-1 (68.8 wt%) at STP with good recyclability. Notably, it also exhibits CO2 adsorption with an uptake capacity of 20.2 cm3 g-1 (3.6 wt%) at room temperature and 1 bar.

Two new mononuclear metal complexes involving the bidentate Schiff base ligand 2,4,6-trimethyl- N -[(pyridin-2-yl)methyl-idene]aniline (C 15 H 16 N 2 or PM-TMA), [Mn(NCS) 2 (PM-TMA) 2 ] ( I ) and [Ni(NCS) 2 (PM-TMA) 2 ] ( II ), were synthesized and their structures determined by single-crystal X-ray diffraction. Although the title compounds crystallize in different crystal systems [triclinic for ( I ) and monoclinic for ( II )], both asymmetric units consist of one-half of the complex mol-ecule, i.e. one metal(II) cation, one PM-TMA ligand, and one N-bound thio-cyanate anion. In both complexes, the metal(II) cation is located on a centre of inversion and adopts a distorted octa-hedral coordination environment defined by four N atoms from two symmetry-related PM-TMA ligands in the equatorial plane and two N atoms from two symmetry-related NCS - anions in a trans axial arrangement. The tri-methyl-benzene and pyridine rings of the PM-TMA ligand are oriented at dihedral angles of 74.18 (7) and 77.70 (12)° for ( I ) and ( II ), respectively. The subtle change in size of the central metal cations leads to a different crystal packing arrangement for ( I ) and ( II ) that is dominated by weak C-H⋯S, C-H⋯π, and π-π inter-actions. Hirshfeld surface analysis and two-dimensional fingerprint plots were used to qu-antify these inter-molecular contacts, and indicate that the most significant contacts in packing are H⋯H [48.1% for ( I ) and 54.9% for ( II )], followed by H⋯C/C⋯H [24.1% for ( I ) and 15.7% for ( II )], and H⋯S/S⋯H [21.1% for ( I ) and 21.1% for ( II )]., (© Jittirattanakun et al. 2020.)

The title compound, C 8 H 4 Br 2 O 4 ·C 2 H 6 O 2 , crystallizes with one-half of a 2,5-di-bromo-terephthalic acid (H 2 Br 2 tp) mol-ecule and one-half of an ethyl-ene glycol (EG) mol-ecule in the the asymmetric unit. The whole mol-ecules are generated by application of inversion symmetry. The H 2 Br 2 tp mol-ecule is not planar, with the di-bromo-benzene ring system inclined by a dihedral angle of 18.62 (3)° to the carb-oxy-lic group. In the crystal, the H 2 Br 2 tp and EG mol-ecules are linked into sheets propagating parallel to (01) through O-H⋯O hydrogen bonds, thereby forming R 4 4 (12) and R 4 4 (28) graph-set motifs. Br⋯O and weak π-π stacking inter-actions are also observed. Hirshfeld surface analysis was used to confirm the existence of these inter-actions.

The crystal structure of the title compound, cadmium sulfate monohydrate or poly[(μ2-aqua)(μ4-sulfato)-cadmium], was redetermined based on modern CMOS (complementary metal oxide silicon) data. In comparison with the previous study [Bregeault & Herpin (1970 ▸). Bull. Soc. Fr. Mineral. Cristallogr. 93, 37-42], all non-H atoms were refined with anisotropic displacement parameters and the hydrogen-bonding pattern unambiguously established due to location of the hydrogen atoms. In addition, a significant improvement in terms of precision and accuracy was achieved. In the crystal, the Cd(2+) cation is coordinated by four O atoms of four sulfate anions and two O atoms of water mol-ecules, forming a distorted octa-hedral trans-[CdO6] polyhedron. Each sulfate anion bridges four Cd(2+) cations and each water mol-ecule bridges two Cd(2+) cations, leading to the formation of a three-dimensional framework, with Cd⋯Cd separations in the range 4.0757 (2)-6.4462 (3) Å. O-H⋯O hydrogen-bonding inter-actions of medium strength between the coordinating water mol-ecules and sulfate anions consolidate the crystal packing.

The title compound, [Ag2Mn(CN)4(C10H8N2)] n or Mn(bipy){Ag(CN)2}2 (bipy = 2,2'-bi-pyridine) is isostructural with Cd(bipy){Au(CN)2}2 [Guo et al. (2009 ▸). CrystEngComm, 11, 61-66]. The Mn(II) atom has crystallographically imposed twofold symmetry and a distorted octa-hedral coordination sphere consisting of six N atoms from one bi-pyridine ligand and four di-cyano-argentate(I) anions, [Ag(CN)2](-), while the Ag(I) atom of the complex anion displays the expected linear geometry. Each [Ag(CN)2](-) unit connects to two neighbouring [Mn(bipy)](2+) cations to give an threefold inter-penetrating quartz-like three-dimensional framework. No directional inter-actions beyond van der Waals contacts are observed.

The title Schiff base compound, C25H20N2, crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. In both mol-ecules, the imine group is approximately coplanar with the pyridine ring, with N-C-C-N torsion angles of 170.1 (3) and -172.0 (3) Å. In the crystal, A and B dimers are linked by pairs of C-H⋯π inter-actions and further C-H⋯π bonds link the dimers into a three-dimensional network.

The asymmetric unit of the title complex, [Ni(C₁₀H₈N₂)(H₂O)₄]SO₄, consists of a complex [Ni(bipy)(H₂O)₄]²⁺ cation (bipy = 2,2'-bipyridine) and a non-coordinating [SO₄]²⁻ anion. The Ni(II) atom is six-coordinated in a distorted octa-hedral geometry defined by the two N atoms of the bipy ligand and four water O atoms. The crystal structure contains extensive classical O-H⋯O hydrogen bonds, which link the ions into a two-dimensional array in the ab plane. Layers are connected into a three-dimensional supra-molecular structure by C-H⋯O inter-actions.