Ferrocene­carb­oxy­lic anhydride: identification of a new polymorph

A new polymorph of ferrocene­carb­oxy­lic anhydride was obtained, characterized and its structural features compared with those of other cyclo­penta­diene­carb­oxy­lic anhydrides.

Crystal structure of pharmaceutical cocrystals of 2,6-di­amino­pyridine with piracetam and theophylline

Two cocrystals of 2,6-di­amino­pyridine with the active pharmaceutical ingredients (APIs) piracetam and theophylline were prepared by the solvent-assisted grinding method.

Crystal structure and proton conductivity of a new Cs₃(H₂PO₄)(HPO₄)·2H₂O phase in the caesium di- and mono­hydrogen orthophosphate system

The compound Cs₃(H_1.5PO₄)₂·2H₂O has been synthesized and its crystal structure has been determined. The thermal and proton-transport properties of the compound have been investigated.

Coca­ethyl­ene, the in vivo product of cocaine and ethanol, is a narcotic more potent than its precursors

Cocaethylene is a narcotic produced in vivo when cocaine and ethanol are administered concomitantly. The molecular conformation and supramolecular architecture of cocaethylene have been determined for the first time.

Reduced 3,4′-bi­pyrazoles from a simple pyrazole precursor: synthetic sequence, mol­ecular structures and supra­molecular assembly

Structures are reported for four compounds along a synthetic pathway to bi­pyrazoles. The supra­molecular assemblies range from isolated mol­ecules via a simple hydrogen-bonded chain of rings and a ribbon of edge-fused hydrogen-bonded rings to a hydrogen-bonded sheet.

Structural characterization, gelation ability, and energy-framework analysis of two bis­(long-chain ester)-substituted 4,4′-bi­phenyl compounds

Although 4,4′-bis­[5-(meth­oxy­carbonyl)pentyl­oxy]biphenyl (BBO6-Me) and 4,4′-bis­[5-(eth­oxy­carbonyl)pentyl­oxy]biphenyl (BBO6-Et) are isostructural, BBO6-Me behaves as an organo­gelator, whereas BBO6-Et does not under the conditions examined. Inter­molecular inter­actions are explored using Hirshfeld surfaces, fingerprint plots, interaction energies, and energy frameworks.

Planarity of benzoyl­thio­carbazate tuberculostatics. IV. Polymorphs of N′-(1,3-di­thio­lan-2-yl­idene)-4-nitro­benzohydrazide

The structures of three packing polymorphs and one hydrate of a potentially tuberculostatic derivative of hydrazide were determined by X-ray diffraction.

N—H⋯X (X = Cl and Br) hydrogen bonds in three isomorphous 3,5-di­chloro­pyridinium salts

N—H⋯X (X = Cl and Br) hydrogen bonds are the dominating short contacts in three isomorphous 3,5-di­chloro­pyridinium salts. Triangular halogen inter­actions contribute to a minor extent.

Hy­droxy­tropylium chloride: the first crystal structure of an unfunctionalized hy­droxy­tropylium ion

The crystal structure of hy­droxy­tropylium chloride represents the first crystallographic characterization of an unfunctionalized hy­droxy­tropylium ion.

Unexpected beauty and diversity in the structures of three homologous 4,5-di­alk­oxy-1-ethynyl-2-nitro­benzenes: the subtle interplay between intermolecular C—H⋯O hydrogen bonds and alkyl chain length

Intermolecular sp- and sp²-C—H⋯O hydrogen bonds dominate the intermolecular interactions in the structures of a series of 1,2-di­alk­oxy-4-ethynyl-5-nitro­benzenes, with unexpected beauty and diversity.

Isomorphous rare-earth bis­[bis­(2,6-diiso­propyl­phen­yl)phosphate] complexes and their self-assembly into two-dimensional frameworks by intra­molecular hydrogen bonds

The first heteroleptic di­aryl­phosphate rare-earth complexes have been obtained. Three crystal structures of [Ln{O₂P(O-2,6-ⁱPr₂C₆H₃)₂}₂Cl(CH₃OH)₄]·2CH₃OH (Ln = Nd, Lu and Y) are isomorphous and exhibit intra- and inter­molecular hydrogen bonding, forming a two-dimensional inter­molecular framework. The complex [Nd{O₂P(O-2,6-ⁱPr₂C₆H₃)₂}₂(NO₃)(CH₃OH)₄]·2CH₃OH demonstrates an analogous crystal structure.

A new two-dimensional Cd^II coordination polymer based on 2-(1H-imidazol-1-ylmeth­yl)-6-methyl-1H-benzimidazole and benzene-1,2-di­carboxyl­ate: synthesis, crystal structure and characterization

A new Cd^II coordination polymer based on 2-(1H-imidazol-1-ylmeth­yl)-6-methyl-1H-benzimidazole (immb) and benzene-1,2-di­carboxyl­ate (1,2-bdic²⁻) ligands has been prepared and structurally characterized. The Cd^II ions are linked by bridging immb and 1,2-bdic²⁻ ligands to generate a two-dimensional network structure.

Different supra­molecular architectures mediated by different weak inter­actions in the crystals of three N-aryl-2,5-di­meth­oxy­benzene­sulfonamides

The crystal structures of three closely related N-aryl-2,5-di­meth­oxy­benzene­sulfonamides display different supra­molecular architectures built by various weak inter­molecular inter­actions of the types C—H⋯O, C—H⋯Cl, C—H⋯π(ar­yl), π(ar­yl)–π(ar­yl) and Cl⋯Cl. Hirshfeld surface analysis of these compounds has also been conducted in order to understand the relationship between the crystal structures.