Journal of Chemical Crystallography最新文献

Two bismuth(III) coordination polymers, namely [Bi₂X₆(µ-dtpo)₃]_n [X = Cl (1), Br (2); dtpo = 2,2′-dithiobis(pyridine N-oxide)], were prepared using a crystal engineering strategy and structurally characterized by X-ray crystallography. In the isostructural compounds 1 and 2 (trigonal system, space group P-3c1), fac-configured BiX₃ units as nodes are joined by the C₂-symmetrical dtpo bridging ligand as spacers to generate 2D honeycomb layers with (6,3) topology. The 2D sheets stack along the [001] direction, resulting in virtually hexagonal channels parallel to this direction, which are occupied by disordered methanol and water molecules. The potential solvent area per unit cell volume is 42.2% for 1 and 44.0% for 2.

Graphical Abstract

Two isostructural 2D honeycomb bismuth(III) coordination, synthesized from 2,2′-dithiobis(pyridine N-oxide) and bismuth(III) halides are described.

Crystals of Sodium Laurate, Lauric Acid (NaLLA) were obtained and the structure was determined by single-crystal X-ray diffraction. The new crystal form is monoclinic of space group P2₁/c. The asymmetric unit contains two independent laurate molecules whose carboxylic/carboxylate groups are linked by a low barrier O-H…O hydrogen bond. Two lauric/laurate molecules are in a head-to-head configuration and the elongated hydrophobic chains are parallel to the long b axis. The carboxylic hydrogen atom was found to be disordered, bound on each of the two carboxylate groups in an unsymmetrical way. The non-symmetrical character of the hydrogen bond is related to the presence of two independent fatty acid molecules in the asymmetric unit and is in accordance with the different lengths of the four C-O bonds present in the molecular structure. The crystal structure was analyzed in terms of interactions on the Hirshfeld surface. The packing is stabilized by hydrogen bonds and O…Na ionic interactions in the hydrophilic layer and by C-H…H-C contacts in the hydrophobic layers which are the most enriched major contacts.

New hydrazone derivate, (1Z,2E)-2-(2-(1-(1,3-dimethyl-2,4,6-trioxotetrahydropyrimidin-5(2H)-ylidene)ethyl)hydrazineylidene)-2-(p-tolyl)acetaldehyde oxime (H₂L) was synthesized by 5-acetyl-1,3-dimethyl-barbituric acid and p-methyl isonitrosophenylhydrazine. Its molecular and crystal structures were determined by single crystal X-ray analysis. It belongs to triclinic system P-1 space group with a = 7.1722 (3) Å, b = 10.5362 (4) Å, c = 11.7675 (5) Å, α = 98.844 (4)°, β = 98.882 (4)°, γ = 104.330 (4)°, Z = 2 and V = 833.95 (6) ų. In the molecular structure, the intramolecular N–H···O and N–H···N hydrogen bonds enclose S(6) ring motifs. In the crystal structure, the intermolecular C–H···O and O–H···O hydrogen bonds link the molecules into centrosymmetric dimers, enclosing R₂²(10) and R₄⁴(10) ring motifs, in which they may be effective in stabilization of the structure. The Hirshfeld surface analysis of crystal structure indicates that the most important contributions for crystal packing are from H…H (48.5%), H…O/O…H (23.7%) and H…C/C…H (9.7%) interactions. Hydrogen bonding and van der Waals interactions are the dominant interactions in crystal packing. Computational chemistry indicates that in the crystal, O–H···O and C–H···O hydrogen bond energies are 95.9 and 87.5 kJ mol⁻¹. The evaluation of the electrostatic, dispersion and total energy frameworks indicates that stabilization is dominated via the nearly equal strengths of the electrostatic and dispersion energy contributions.

Graphical Abstract

A new hexavanadate hybrid with alkynyl ligands (DIEA)₂[V₆O₁₃{(OCH₂)₃CNHCOC₆H₄C≡CH}₂] was synthesized and its molecular structure has been determined by single-crystal X-ray diffraction. The compound crystallize in the orthorhombic system, space group Pccn with the cell parameters a = 15.951(2) Å, b = 33.240 Å, c = 10.5960(14) Å, α = β = γ = 90°, V = 5618.2(13) Å ³. The electrostatic potential was also calculated to show the electron distribution in the polyoxoanion.

Graphical Abstract

A new hexavanadate hybrid with alkynyl ligands (DIEA)₂ [V₆O₁₃{(OCH₂)₃CNHCOC₆H₄C≡CH}₂] was synthesized by post-functionalization. Each of the structures looks like a flabellum and both ends are straight and rigid on account of the conjugated effect in the organic ligands.

Mononuclear uranyl(VI) Schiff base complexes of formula [UO₂(L₁)]·py (1·py) {[UO₂(L²)]}₂·MeCN·H₂O (2·MeCN·H₂O) have been prepared and characterized by both IR and ¹H NMR spectroscopy and X-ray crystallography. The complex species 1·py crystallizes as orange needle-like crystals in the orthorhombic space group, Pbca, with 8 molecules per unit cell. Interestingly, the pyridine molecule does not participate in coordination to the metal center and was found as a solvent molecule embedded in the crystal structure with weaker interactions to the metal complex. The crystals of the complex species, 2·MeCN·H₂O, crystallized in a monoclinic form, space group, P2₁, with 2 molecules in the asymmetric unit. The two molecules [(UO₂)(L₂)(CH₃CN or H₂O)] in the asymmetric unit of 2·MeCN·H₂O exhibit a competitive (CH₃CN/H₂O) scenario without any direct coordination to the uranyl ion.

Graphical Abstract

Uranyl(VI) Schiff base complexes of general formula [UO₂(L₁)]·py (1·py) and {[UO₂(L²)]}₂·MeCN·H₂O (2·MeCN·H₂O) have been prepared and characterized by spectroscopic analysis and X-ray crystallography.

Treatment of diphenyl tellurium oxide (Ph₂TeO) with CuCl₂·2H₂O in a 4:1 molar ratio afforded the copper(II) complex [Cu^II(Ph₂TeO)₄]Cl₂·14H₂O (1), in which the copper(II) center is four-coordinated by four oxygen atoms from four Ph₂TeO units. Reaction of MnCl₂·4H₂O, (ⁿBu₄N)[MnO₄] and Ph₂TeO at a molar ratio of 4:1:16 gave the manganese(III) complex [Mn^IIICl(Ph₂TeO)₄]Cl₂·4H₂O (2), in which the manganese(III) center is five-coordinated by one chlorine atom and four oxygen atoms from four Ph₂TeO moieties. Complex 1 crystallizes in the triclinic space group Pī, with a = 8.9904(18), b = 13.068(3), c = 13.573(3) Å, α = 100.42(3)°, β = 109.17(3)°, γ = 99.56(3)°, and Z = 1. The unit cell of 2 has a monoclinic P2₁/c symmetry with the cell parameters a = 20.179(5), b = 13.917(3), c = 19.210(4) Å, β  =  94.840(7)°, and Z = 4.

Graphical Abstract

Two new transition metal complexes with diphenyl tellurium oxide as ligands have been synthesized and studied.

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.