Journal of Chemical Crystallography最新文献

Three Cu(II) complexes of 1,1,1-trifluoroacetylacetonate, viz. [Cu(TFACAC)₂(MeOH)] (1), [Cu(TFACAC)₂(py)] (2) and [Cu(TFACAC)₂(DABCO)] (3) were synthesized and characterized by elemental analysis, IR, UV–Visible spectroscopy and cyclic voltammetry. Structures of complexes 1–3 were established by single crystal X-ray diffraction wherein 1 and 2 adapt square pyramidal geometry. Complex 1 crystallizes in triclinic space group P-₁, with a = 8.5059(6) Å, b = 9.3025(7) Å, c = 10.9906(8) Å, α = 75.684(2)°, β = 73.191(2)°, γ = 64.992(2)°, and Z = 2. X-ray crystallographic studies revealed that in complex 1, both, TFACC ligands and coordinated methanol are disordered over two conformations giving a combination of two isomers with cis to trans isomer ratio of 0.538:0.462. In complex 3 DABCO is acting as a bridging ligand connecting two Cu(II) centers thereby forming a 1-D polymer chain with each copper in octahedral coordination. The cyclic voltammograms of 1 and 3 give a quasi-reversible Cu(II)/Cu(I) peak with E_1/2 + 0.01 V and − 0.05 V respectively whereas complex 2 gives a one electron reversible Cu(II)/Cu(I) couple at E_1/2 = − 0.25 V.

Graphical Abstract

Three Cu(II) complexes of (1,1,1-trifluoroacetylacetonato) ligand with methanol, pyridine and DABCO occupying the axial positions are reported.

The X-ray structure analyses of 4-hydroxy-1-methylquinolin-2(1H)-one (1), 6-ethyl-4-hydroxy-2H-pyrano[3,2-c]quinoline-2,5(6 H)-dione (2), (E)-4-(2-benzylidene-hydrazineyl)quinolin-2(1H)-one (3), and diethyl (E)-2-(2-(1-methyl-2-oxo-1,2-dihydroquinolin-4-yl)hydrazineylidene)-succinate (4), were carried out. The aforementioned compounds showed strong intramolecular hydrogen bonds which play important roles in the crystal packing of them.

Graphical Abstract

Utilizing the facile addition–elimination reaction of thiosemicarbazide with acetone or aldehydes, nine thiosemicarbazones were synthesized. Aldehydes were chosen which contain additional heteroatoms to increase the diversity of possible intermolecular interactions. Further, the thiosemicarbazone synthesis was conducted in situ with one of the common halogen bond donors 1,2-, 1,3-, or 1,4-diiodotetrafluorobenzene, 1,3,5-trifluoro-2,4,6-triiodobenzene, or tetraiodoethylene. These reactions resulted in the characterization of 12 new cocrystals showcasing halogen bonding. The dimerization of two thiosemicarbazone units through a pair of N‒H···S hydrogen bonds was a universal feature of the solid-state structures in this series, with the hydrogen bond network often extending these motifs into chains. The organoiodines serve to link chains through either I···S or I···N halogen bonding, or less commonly, S···I chalcogen bonding. This variety of intermolecular interactions leads to the formation of double-stranded chains, ribbons, and sheets.

Graphical Abstract

Utilizing the facile addition–elimination reaction of thiosemicarbazide with acetone or aldehydes, nine thiosemicarbazones were synthesized, seven of which were isolated as cocrystals with common halogen bond donors. Significant N–H···S hydrogen bonding was observed in all, with S···I halogen and chalcogen bonding contributing to the long-range packing in the cocrystals.

Elemental Te inserts across the C–I bond of in situ generated iodo derivatives of 1,3-dibromopropane, (trimethylsilyl)methyl iodide, benzyl chloride and m-nitro-benzyl bromide to give rise the , (Me₃SiCH₂)₂TeI₂, (C₆H₅CH₂)₂TeI₂, and (m-NO₂-C₆H₄CH₂)₂TeI₂ molecules in good yield respectively. These molecules are characterised by ¹H NMR and elemental analysis techniques. Among these (C₆H₅CH₂)₂TeI₂ and (m-NO₂-C₆H₄CH₂)₂TeI₂ molecules are also characterized by single-crystal X-ray studies. In the packing diagram of (C₆H₅CH₂)₂TeI₂, there are intermolecular Te⋯π-phenyl interaction (3.768 Å) between the tellurium atoms and phenyl rings of adjacent molecule. The crystal packing of (m-NO₂–C₆H₄CH₂)₂TeI₂, displays an interesting supramolecular synthon. This synthon is based on reciprocal several C–H⋯O, C–H⋯I Hydrogen bonding interactions along with Te⋯I Secondary bonding interactions.

Graphical Abstract

A series of high-quality single crystals of the formula Na_xK_1−xAlSiO₄ were synthesized using a high temperature hydrothermal method. This enabled the detailed single crystal study of four examples of this class of compounds, namely KAlSiO₄, Na_0.10K_0.90AlSiO₄ Na₃KAl₄Si₄O₁₆ and NaAlSiO₄. The potassium-containing species all had fully ordered AlO₄ and SiO₄ tetrahedral sites that led to formation of polar acentric structures. In contrast NaAlSiO₄ displayed the unusual feature of an exceptionally large and complex unit cell along with complete disordering of the Al and Si sites. This led to the formation of a centrosymmetric structure, that is also a new polymorph of the NaAlSiO₄ composition. The polymorphism of hydrothermal KAlSiO₄ was also examined in light of the crystal’s synthetic and thermal histories. The study also revealed a structural sensitivity toward the degree of Na/K substitution in the lattice. The strong tendency to form polar acentric structures makes understanding these structures of great interest. These detailed structures resolved a considerable degree of previous structural ambiguity within this nominally simple class of compounds.

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Structural subtleties are examined in the nepheline–kalsilite series of Na_xK_1−xAlSiO₄, revealing changes in the resulting structure according to synthetic method, thermal history, and alkali metal substitution.

Two Cd(II) complexes, [Cd(CMOPAA)(Phen)(H₂O)]_n (1) and [Cd(CMOPAA)(Bipy)]_n (2), (H₂CMOPAA = 4-carboxymethoxy-3-phenylacrylic acid, Phen = 1,10-phenanthroline and 2,2′-bipyridine = Bipy) were synthesized with 4-carboxymethoxy-3-phenylacrylic acid ligands by solvothermal condition and structurally characterized by element analysis, IR, TGA and single crystal X-ray diffraction. Complex 1 crystalizes in the monoclinic system, space group C2/c with a = 12.4609 (11) Å, b = 18.7973 (16) Å, c = 13.4544 (12) Å, β = 99.732 (1)°, V = 3106.1 (5) ų. The asymmetric unit of complex 1 consists of one Cd(II) ion, one CMOPAA²⁻ ligand, one Phen ligand and one H₂O. Cd(II) ion is an eight-coordinated distorted dodecahedron geometry. Each CMOPAA²⁻ ligand coordinates with two adjacent Cd(II) ions to form a one-dimensional chain. Complex 2 crystalizes in the triclinic system, space group P-1 with a = 9.407 (3) Å, b = 9.838 (3) Å, c = 11.792 (4) Å, α = 83.974 (4)°, β = 78.392 (3)°, γ = 67.019 (3)°, V = 983.7 (5) ų. The asymmetric unit of complex 2 consists of one Cd(II) ion, one CMOPAA²⁻ ligand and one Bipy ligand. Cd(II) ion is a seven-coordinated twisted single-cap triangular prism configuration. The hexadentate bridging CMOPAA²⁻ ligands coordinates with four adjacent Cd(II) ions to form a one-dimensional chain. The tetradentate bridging CMOPAA²⁻ ligands link the neighboring one-dimensional chains to form a novel two-dimensional network structure.

Graphical Abstract

Two Cd(II) complexes, [Cd(CMOPAA)(Phen)(H₂O)]_n (1) and [Cd(CMOPAA)(Bipy)]_n (2), (H₂CMOPAA = 4-carboxymethoxy-3-phenylacrylic acid, Phen = 1,10-phenanthroline and 2,2′-bipyridine = Bipy) were synthesized with 4-carboxymethoxy-3-phenylacrylic acid ligands and structurally characterized by element analysis, IR, TGA and single crystal X-ray diffraction. Complex 1 is a one-dimensional chain and complex 2 is a two-dimensional network structure.

Co-crystal structure of inclusion complex based on macrocyclic host of octabromo-functionalized pillar[5]arene (PilBr8) and guest 1-bromooctane (OctBr) molecule is discussed. The host-guest interactions are achieved by efficient C–H⋅⋅⋅O and C–H⋅⋅⋅π nonbonding interactions. The packing pattern of the crystal structure shows the inclusion-complex [PilBr8⊃OctBr] formed one-dimensional supramolecular polymer network driven by Br⋅⋅⋅H and Br⋅⋅⋅Br non-bonding interactions. Hirshfeld surface analysis revealed that the guest molecule plays an important role in formation of self-assembled linear supramolecular polymer trough head-to-tail halogen bond (Br⋅⋅⋅H).

Graphical Abstract

Co-crystal ofinclusion complex based on bromo-functionlized pillar[5]arene with1-bromooctane displays the assembly of linear supramolecular polymer promotedby halogen-bonding interactions.

Crystals of the title compound BiCuI₅(phen)₂ were synthesized solvothermally by reacting CuCl₂·2H₂O, Bi(NO₃)₃·5H₂O, NH₄I, and 1,10-phenanthroline in an ethanol/water solvent mixture. BiCuI₅(phen)₂ crystallizes in the monoclinic space group P2₁/n. The asymmetric unit consists of a [Bi₂I₁₀] iodobismuthate group and a [CuI(phen)₂] complex that are linked via a shared iodine. In this paper, we describe the synthesis and single crystal structure of the new metal–organic halobismuthate complex, BiCuI₅(phen)₂.

Graphical Abstract

X-ray diffraction quality single crystals of a novel metal–organic halobismuthate, BiCuI₅(phen)₂ were grown in water/ethanol solvent mixture at 120 °C and used for structure determination using single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P2₁/n.

In this work, we apply the concept of tolerance factors (t) to pyrochlore solid solution, particularly when the B-site contains two different ions with different masses (as well as charge states) in the formula unit ({A}_{2}^{3+}{B}^{3+}{B}^{{{prime}}5+}{O}_{7}) as in the present sample of A₂BSbO₇ (A³⁺ = Y, Dy, Gd, Bi; B³⁺ = Fe, Ga). We examine the previous tolerance factor and proposed a model of lattice constant (a) that depends only on the ionic radii R_A, R_B (= (frac{Rleft(Feright)+R(Sb)}{2}) or (frac{Rleft(Garight)+R(Sb)}{2})) and R_O. Then we proposed an empirical tolerance factor (t), that depends only on the ({R}_{A},{R}_{B},{mathrm{ and },R}_{O}) of the constituent atoms. We discuss the structural stability field and property features of mixed pyrochlore oxide compounds before measuring their structural data as for the case of perovskites.

Graphical abstract

In the present work, we have proposed the empirical formula of lattice constant of A₂BSbO₇ (A³⁺ = Y, Dy, Gd, Bi; B³⁺ = Fe, Ga) of formula unit ({A}_{2}^{3+}{B}^{3+}{B}^{{{prime}}5+}{O}_{7}) and hence find the tolerance factor, which predict the structural stability field and property features of mixed pyrochlore oxide compounds before measuring their structural data as for the case of perovskites. Caption: Errors (in %) between the calculated and experimental lattice constants. In the above figure, we shown that the errors (%) between the calculated and experimental lattice constants found from empirical lattice formula a = (frac{8}{sqrt{3}}left[1.4474357143left({R}_{A}+{R}_{O}right)-0.42931frac{{left({R}_{A}+{R}_{O}right)}^{2}}{({R}_{B}+{R}_{O})}right]) and Rietveld analysis of powder diffraction data respectively. The error of predicting for the lattice constant by Brik and Srivastava (J Am Ceram Soc 95:1454–1460, 2012) is moderately higher than the error (≤ 0.523%) obtains by our model for mixed pyrochlore oxides.

Two new copper(II) complexes [Cu(L¹)₂(NO₃)]NO₃1 and [Cu(L²)(H₂O)₂](NO₃)₂2(L¹ = 2(2-pyridyl)benzimidazole and L² = 2-benzoylpyridine) have been prepared and characterized by elemental and spectral (UV–visible, FTIR and epr) techniques. Crystal structures of these complexes were determined using single crystal X-ray diffraction analysis. The low value of magnetic moments 1.75 BM for 1 and 1.73 BM for 2 and unusual X-band epr spectral pattern authenticate the antiferromagnetic behavior of complexes. The single crystal X-ray analysis reveals the development of supramolecular architectures through various non-covalent weak interactions such as CH (cdotsuppi) and lp (cdotsuppi) interactions. In order to see the stability of complexes, density functional theory (DFT) calculations were carried out. From the energy gap (ΔE) of frontier molecular orbitals (various molecular descriptors were also evaluated. In addition, superoxide dismutase SOD) activities of both complexes were also determined. The enhanced SOD activity of 1 is due to loosely bound nitrate ion.

Graphical Abstract

Two new copper(II) complexes [Cu(L¹)₂(NO₃)]NO₃ and [Cu(L²)(H₂O)₂](NO₃)₂ (L¹= 2(2-pyridyl)benzimidazole and L²= 2-benzoylpyridine) have been prepared and characterized by elemental, spectral, and single crystal diffraction techniques