Structure and spectroscopic properties of the dimeric copper(I) N-heterocyclic carbene complex [Cu₂(CNC_t-Bu)₂](PF₆)₂

In a dimeric copper(I) complex bridged by two bis­(N-heterocyclic carbene)pyridine ligands, each Cu^I atom is almost linearly coordinated and no cuprophilic inter­actions were observed. The complex is a new example of a multinuclear copper N-heterocyclic carbene complex and a member of a compound class which has only rarely been reported.

Weak C—H⋯O and C—H⋯π hydrogen bonds and π–π stacking inter­actions in a series of four N′-[(E)-(ar­yl)methyl­idene]-N-methyl-2-oxo-1,3-oxazolidine-4-carbohydrazides

Numerous different weak C—H⋯O and C—H⋯π bonds and π–π stacking inter­actions are observed in the structures of four oxazolidine-4-carbohydrazides. None are universal in the four structures and they play an unpredictable role in establishing the packing in this family of compounds.

N-(6-Methyl­pyridin-2-yl)mesitylenesulfonamide and acetic acid – a salt, a cocrystal or both?

Cocrystal or salt? The position of a proton may decide! In the case of a sulfonamide derivative and acetic acid, the answer may depend on temperature.

Multiple N—H⋯NC, C—H⋯NC and nitrile⋯π inter­actions in 4,4′-bi­pyridine-1,1′-diium bis­(1,1,3,3-tetra­cyano-2-eth­oxy­propenide): structure determination and DFT calculations of anion⋯π cation inter­action energies

In 4,4′-bi­pyridine-1,1′-diium 1,1,3,3-tetra­cyano-2-eth­oxy­propenide, the ions are linked by separate networks of N—H⋯NC, C—H⋯NC and two types of multicenter anion⋯π cation inter­actions. A weak nitrile⋯π inter­action between adjacent anions is also present. DFT calculations were used to estimate the strength of the observed inter­actions.

Anisole at 100 K: the first crystal structure determination

In the structure of anisole (meth­oxy­benzene) at 100 K, the arrangement of mol­ecules in the solid state appears to be governed by close packing. No face-to-face π–π stacking of the mol­ecules is observed, but rather edge-to-face inter­actions result in a herringbone packing motif.

Two novel ferrocenyl dipeptide-like compounds generated via the Ugi four-component reaction

The supra­molecular structures of two novel ferrocenyl dipeptide-like compounds generated via the Ugi four-component reaction are reported.

Synthesis and crystal structures of two coordination polymers and a binuclear cadmium(II) complex containing 3- and 4-amino­benzoate ligands

Two coordination polymers and a binuclear cadmium(II) complex containing 3- and 4-amino­benzoate ligands have different structural forms, i.e. a one-dimensional ladder structure, a one-dimensional chain structure and a binuclear mol­ecular structure. The ligands display versatile coordination modes and can be of use in the construction of metal–organic frameworks with potential practical applications.

A new linear bis­muth coordination polymer based on 1,10-phenanthroline-2,9-di­carb­oxy­lic acid: ionothermal synthesis, crystal structure and fluorescence properties

Within the structure of the one-dimensional coordination polymer structure formed from bismuth(III) and 1,10-phenanthroline-2,9-di­carboxyl­ate, each Bi^III centre is seven-coordinated by one Cl atom, four carboxyl­ate O atoms and two phenanthroline N atoms in a distorted penta­gonal–bipyramidal arrangement. The three-dimensional supra­molecular architecture is assembled via weak C—H⋯O and C—H⋯Cl hydrogen bonds.

Syntheses and structures of one Cu^I-containing coordination polymer and two macrocyclic supra­molecular complexes based on flexible 1,3,4-oxa­diazole-containing ligands

Two macrocyclic supra­molecular and a one-dimensional Cu^I-containing coordination polymer have been prepared using symmetrical flexible 1,3,4-oxa­diazole-containing organic ligands. Subtle changes in the flexible ligand geometries and different counter-anions result in remarkable changes in the final structures.

Monoreduced 1,2-di­hydro­corannulene versus the parent corannulene

Monoreduced 1,2-di­hydro­corannulene has been isolated in the form of the potassium salt and structurally characterized for the first time. The X-ray study confirms the previous NMR spectroscopic prediction that the two H atoms are attached to the same six-membered ring to form 1,2-di­hydro­corannulene, thus destroying the aromaticity of only one benzene ring of the corannulene core.

Polymorphism of di­nitro­[tris­(2-amino­eth­yl)amine]­cobalt(III) chloride

Of three polymorphs of di­nitro­[tris­(2-amino­eth­yl)amine]­cobalt(III) chloride, two ortho­rhom­bic polymorphs are related by a solid-state enanti­otropic order–disorder phase transition at ca 152 K and the third, monoclinic, polymorph crystallizes as a nonmerohedral twin.

A new two-dimensional Zn^II coordination polymer constructed by a multidentate N-heterocyclic ligand and 5-carb­oxy­benzene-1,3-di­carboxyl­ate

In a new two-dimensional zinc(II) coordination polymer based on a multidentate N-heterocyclic ligand and 5-carb­oxy­benzene-1,3-di­carboxyl­ate, layers are formed by the Zn^II ions being bridged by both types of ligands. Adjacent layers are further connected by hydrogen bonds and π–π inter­actions, resulting in a three-dimensional supra­molecular architecture in the solid state.

Diamondoid framework solid with Sn(OCH₃)₂–tetra­pyridyl­porphyrin linkers, Cu^I nodes and [Cu^ICl₂]⁻ counter-ions

This study describes a unique tin–tetra­pyridyl­porphyrin-based metal–organic framework (MOF) in which square-planar organic linkers are inter­connected via Cu^I connectors with a tetra­hedral coordination environment into a three-dimensional single-framework architecture of PtS topology.

A linear bridging angle in the pyrovanadate group within the crystal structure of Hg₂V₂Te₂O₁₁

The structure of Hg₂V₂Te₂O₁₁ represents a rare example where two corner-sharing XO₄ tetra­hedra exhibit a linear X—O—X bridging angle without a noticeable thermal motion or disorder perpendicular to the X⋯X axis. The corresponding [V₂O₇] divanadate group has a staggered conformation.

A two-dimensional anionic Cd^II polymer constructed through dicyanamide coordination bridges

In a new two-dimensional organic–inorganic hybrid cadmium dicyanamide complex with 4-di­methyl­amino-1-ethyl­pyridin-1-ium counter-cations, the Cd^II cation is octa­hedrally coordinated by six terminal N atoms from six anionic dicyanamide ligands. The potential of this compound as a phase-transition material was investigated.

Three structures of di­spiro­oxindole derivatives generated in situ through a three-component one-pot strategy with complete regio- and stereoselectivity

Three di­spiroxo­indole derivatives reveal salient features for understanding the diastereoselectivity of the [3+2] cyclo­addition reaction. The trans orientation of carbonyl groups of the oxindole ring systems and the H atoms of the di­hydro­furan ring facilitate C—H⋯O and π–π inter­actions, and contribute to the diastereoselectivity.

Isostructural organic–inorganic hybrid compounds: tri­ethyl­choline tri­bromido­cadmate and tri­ethyl­choline tri­bromido­mercurate

In two isostructural organic–inorganic hybrid halometallate compounds, the metal centres are five-coordinated by bromide anions and the crystal structures consist of one-dimensional edge-sharing chains of MBr₅ trigonal bipyramids between which tri­ethyl­choline counter-cations are inter­calated.

Unusual hydrogen bonding in L-cysteine hydrogen fluoride

L-Cysteine hydrogen fluoride consists of L-Cys⁺(L-Cys⋯L-Cys⁺)F⁻(F⁻⋯HF) units. The A⁺(A⋯A⁺) type cation without a doubly charged anion has been found for the first time.

Di­hydro­oxazolones and di­hydro­imidazolo­nes derived from acyl­glycines: syntheses, mol­ecular structures and supra­molecular assembly

A simple reaction pathway to alkyl­idene-substituted di­hydro­oxazolones and di­hydro­imidazolo­nes from acyl­glycines is described, along with further reactions of a di­hydro­oxazolone to form either a 2-substituted acyl­glycinehydrazide, which can also be converted into a di­hydro­imidazolone, or a 2-substituted acyl­glycine. The thienyl-substituted products generally exhibit orientational disorder in the thienyl groups, and hydrogen bonding generates a range of zero-, one- and two-dimensional supra­molecular assembly types.