Optically active derivatives of terephthalic acid: four crystal structures from two powder patterns

Four crystal structures were determined for two terephthalic acid derivatives from two high-resolution synchrotron powder diffraction patterns.

Topological identification of the first uninodal 8-connected lsz MOF built from 2,2′-di­fluoro­biphenyl-4,4′-di­carboxyl­ate pillars and cadmium(II)–triazolate layers

The first three-dimensional Cd^II-based MOF material with 2,2′-di­fluoro­biphenyl-4,4′-di­carb­oxy­lic acid was synthesized and structurally characterized to show a uninodal 8-connected lsz topology.

First-row transition metal–pyridine (py)–sulfate [(py)_xM](SO₄) complexes (M = Ni, Cu and Zn): crystal field theory in action

The crystal structures of first-row transition metal (Ni, Cu and Zn) complexes of the form [(py)_xM](SO₄) are presented. Though crystals for the different metals were isolated under the same reaction conditions, the resulting complexes possess different metal coordination geometries that clearly illustrate the effects of crystal field stabilization energy (CFSE).

On the effect of Ga and In substitutions in the Ca₁₁Bi₁₀ and Yb₁₁Bi₁₀ bis­muthides crystallizing in the tetra­gonal Ho₁₁Ge₁₀ structure type

The Ca₁₁Bi₁₀ and Yb₁₁Bi₁₀ bis­muthides are shown to be amenable to a range of Ga and In substitutions. The resultant structure shows a specific site preference for the Group 13 element, concomitant with an unusual redistribution of the Bi—Bi bond lengths. This structural response of the anionic sublattice is apparently related to the drive of the system toward a charge-balanced state.

New solvates of the drug naltrexone: protonation, conformation and inter­play of synthons

The structures of the ethyl acetate and diethyl ether solvates of naltrexone, an important morphine-related drug used for combating alcoholism and opioid dependence, are reported. Approaches on drug protonation, conformation and synthons are established among these solvates and previously reported crystal forms of naltrexone.

Different supra­molecular inter­actions mediated by Br atoms in the crystal structures of three anisole derivatives

Three anisole building blocks featuring pendant bis­(hy­droxy­meth­yl) or bis­(bromo­meth­yl) have been analyzed with regard to their mol­ecular structures and packing behaviour. A typical supra­molecular pattern involved C—H⋯π inter­actions generating mol­ecular stacks, while π–π inter­actions were only observed in the absence of bromine, indicating a striking influence on the distances between adjacent aromatic moieties.

3,4-Lutidinium salts with the di­iodido­aurate(I) anion: structure of [(3,4-lut)₂H]⁺·[AuI₂]⁻ and of two polymorphs of [(3,4-lut)₂H⁺]₂·[AuI₂]⁻·I⁻

Reactions between potassium tetra­iodido­aurate(III) and pyridine or 3,4-lutidine (3,4-di­methyl­pyridine) were tested as possible sources of aza­aromatic complexes of gold(III) iodide, but all identifiable products contained gold(I).

Synthesis and crystal structure of a new Cu₃Au-type ternary phase in the Au–In–Pd system: distribution of atoms over crystallographic positions

A new ternary phase found in the AuPd-rich part of the Au–In–Pd system belongs to the Cu₃Au type and has a broad homogeneity range based on extensive (Pd,Au) and (In,Au) replacement. The (Au,In,Pd)₃(Pd,Au) model provides a uniform description for three samples of different composition and agrees well with the fact that the homogeneity range of this phase on the phase diagram is inclined to the Au corner.

Effect of pH on the charge-assisted hydrogen-bonded assembly of the anionic [Cu(oxalate)₂]²⁻ building unit and N,N′-ditopic cations

The influence of pH on the solvothermal reaction of Cu(NO₃)₂·3H₂O, Na₂(C₂O₄) and the N,N′-ditopic organic ligands 1-(pyridin-4-yl)piperazine and 1,2-bis­(pyridin-4-yl)ethane has been studied. For an acidic pH value of 2, a one-dimensional zigzag chain structure and a discrete ionic structure, respectively, were obtained.

Zirconium tetra­chloride revisited

ZrCl₄ has been prepared from the reaction of Zr metal and Cl₂ gas in a sealed tube and its structure determined at 100, 150, 200, 250, and 300 K. The chain motif is similar to that observed previously in ZrCl₄, but the structural parameters and space group differ.

A concise, efficient and versatile synthesis of amino-substituted benzo[b]pyrimido[5,4-f]azepines: synthesis and spectroscopic characterization, together with the mol­ecular and supra­molecular structures of three products and one inter­mediate

Amino-substituted benzo[b]pyrimido[5,4-f]azepines can be produced in two steps from 5-allyl­chloro­pyrimidines. The mol­ecular and supra­molecular structures of three such products and of one reaction inter­mediate are reported.

Structure determination of phase II of the anti­fungal drug griseofulvin by powder X-ray diffraction

The crystal structure of the recently detected phase II of the widely used anti­fungal drug griseofulvin has been solved by powder X-ray diffraction. The symmetry is ortho­rhom­bic (space group P2₁2₁2₁) and the asymmetric unit contains two mol­ecules.

Supra­molecular architectures in cytosinium 6-chloro­nicotinate monohydrate and 5-bromo-6-methyl­isocytosinium hydrogen sulfate

In the new salts cytosinium 6-chloro­nicotinate monohydrate and 5-bromo-6-methyl­isocytosinium hydrogen sulfate, the pyrimidine ring is protonated at the N3 atom. The crystal structures of the salts exhibit various hydrogen bonds generating different ring motifs. Further stabilization is provided by weak π–π inter­actions in the former salt and halogen inter­actions in the latter.

A new copper(II) supra­molecular coordination polymer and a dinuclear compound with multifunctional 2-amino-5-sulfo­benzoic acid and flexible N-donor ligands: synthesis, structure and characterization

A new Cu^II supra­molecular coordination polymer and an asymmetric dinuclear compound have been synthesized from multifunctional 2-amino-5-sulfo­benzoic acid and flexible N-donor ligands and their structures have been determined.

Three zinc iodide complexes based on phosphane ligands: syntheses, structures, optical properties and TD–DFT calculations

ZnI₂(PPh₃)₂ and ZnI₂[(p-Tol)₃P]₂ (p-Tol is p-toluene) are both mononuclear four-coordinated ZnI₂ complexes, while [Zn(dppmO₂)₃][ZnI₄] [dppmO₂ is bis­(di­phenyl­phosphor­yl)methane] is composed of a [Zn(dppmO₂)₃]²⁺ cation and a [ZnI₄]²⁻ anion. The acentric space group of ZnI₂[(p-Tol)₃P]₂ suggests it as a potential second-order NLO material. A TD–DFT study demonstrates that the photoluminescence should be derived from the emissive XLCT excited state.

Topological study of diverse hydrogen-bonded patterns found in a system of a nickel(II) complex and the sulfate anion

Bis[2,6-bis­(1H-benzimidazol-2-yl)pyridine]­nickel(II) units combine via sulfate bridges to produce porous solids, connected via strong charge-assisted hydrogen bonds. The frameworks are analyzed using crystallographic and topological approaches.

New quaternary carbide Mg_1.52Li_0.24Al_0.24C_0.86 as a disorder derivative of the family of hexa­gonal close-packed (hcp) structures and the effect of structure modification on the electrochemical behaviour of the electrode

The crystal structure of the new hexgonal quaternary carbide Mg_1.52Li_0.24Al_0.24C_0.86 has been determined by single-crystal X-ray diffraction and represents the stucture family based on hexa­gonal close-packed structures.

Hydro­thermal synthesis, crystal structure and properties of a two-dimensional uranyl coordination polymer based on a flexible zwitterionic ligand

The hydro­thermal reaction of various uranyl compounds with flexible zwitterionic 1,1′-[1,4-phenyl­enebis(methyl­ene)]bis­(pyridin-1-ium-4-carboxyl­ate) di­hydro­chloride resulted in the formation of a novel two-dimensional uranyl coordination polymer, which exhibits a layered arrangement with the (UO₂)²⁺ centre coordinated by five equatorial O atoms.

The role of different nonspecific inter­actions and halogen contacts in the crystal structure organization of 5-chloro­isatoic anhydride

The crystal structure of 5-chloro­isatoic anhydride has been determined and analysed with respect to connectivity and packing patterns. The role of weak and nonspecific inter­molecular inter­actions is elucidated.

Crystal structure and Hirshfeld surface analysis of the anhydrous form of the nucleoside analogue entecavir

The single-crystal structure for the anhydrous crystalline form of the anti-HBV drug entecavir is reported for the first time. It presents significantly different hydrogen-bonding and packing patterns to the hydrated form.

Two novel lanthanide(III) organic frameworks based on a bi­phenyl­tetra­carboxyl­ate ligand: synthesis, structure and magnetic and luminescence properties

Two new two-dimensional lanthanide coordination polymers have been synthesized under solvothermal conditions from biphenyl-3,3′,5,5′-tetra­carb­oxy­lic acid (H₄bpt) and Ln(NO₃)₃·6H₂O (Ln = Tb and Eu). Topological analysis shows that the bpt⁴⁻ ligand and the {Ln₂(μ₂-CH₃COO)₂} building unit could be considered as a (4,6)-connected network with sql topology. A magnetic investigation shows the presence of anti­ferromagnetic inter­actions in the Tb compound.

Reassessment of paracetamol ortho­rhom­bic Form III and determination of a novel low-temperature monoclinic Form III-m from powder diffraction data

A powder X-ray diffraction (PXRD) study of the ortho­rhom­bic polymorph Form III of paracetamol revealed the existence of a reversible phase transition at 170–220 K to a novel monoclinic Form III-m. The crystal structure of Forms III and III-m have both been determined using high-resolution PXRD data and are compared to the published structures of polymorphs Form I and II and an earlier model of Form III.

Planarity of hetero­aryl­dithio­carbazic acid derivatives showing tuberculostatic activity: structure–activity relationships

The structures of three new potentially tuberculostatic compounds were determined by X-ray diffraction. Their activities against other Gram-positive bacteria were also determined.