Cherif Ben Nasr

Likelihood of atom–atom contacts in crystal structures of halogenated organic compounds

The analysis, based on Hirshfeld surfaces, reveals which atoms are the preferred partners of halogens in crystal packing contacts.

The organic–inorganic hybrid material 1-cyclohexylpiperazine-1,4-diium tetrachloridozincate

In the crystal structure of the title organic-inorganic hybrid material, (C10H22N2)[ZnCl4], the tetrachloridozincate anions and 1-cyclohexylpiperazine-1,4-diium dications are interconnected via N-H...Cl and C-H...Cl hydrogen bonds to form layers parallel to the (001) plane. The cyclohexyl groups from adjacent chains interdigitate, thus building the three-dimensional structure. The piperazinium and cyclohexyl rings exhibit regular spatial chair conformations. The title salt was also characterized by FT-IR and Raman spectroscopic analyses.

Bis[4-(dimethyl­amino)­pyridinium] tetra­chloridozincate

In the title compound, (C7H11N2)2[ZnCl4], [ZnCl4]2− anions and 4-(dimethylamino)pyridinium cations are held together by various intermolecular interactions including Coulombic attraction, hydrogen bonding and π–π stacking interactions. Three Cl atoms of the [ZnCl4]2− tetrahedron act as acceptors in N—H⋯Cl hydrogen bonds. The hydrogen bonds, both of which are bifurcated, lead to the formation of a three-dimensional network. Within the network, intermolecular π–π stacking interactions with a centroid–centroid distance of 3.5911 (7) Å arrange the 4-(dimethylamino)pyridinium cations into antiparallel dimers.

Crystal Structure, Spectroscopic and Thermal Investigations of a New 4-Ammonio-2,2,6,6-tetramethylpiperidinium Tetrachlorozincate(II)

The new complex of Zn(II) with 4-ammino-2,2,6,6-tetramethylpiperidine, [C9H22N2]ZnCl4, has been prepared and characterized by various physicochemical studies. This compound crystallizes in the monoclinic system, with the space group P21/c and the following cell parameters: a = 9.8682(7), b = 7.5164(5), c = 21.019(2) A, β = 99.003 (7)°, V = 1539.8(2) A3 and Z = 4. The crystal structure was solved and refined to R = 0.024 using 3070 reflections. The atomic arrangement can be described by slightly distorted tetrahedral ZnCl42- anions and 4-ammmonio-2,2,6,6-tetramethylpiperidinium cations holding together by different interactions. The four chlorine atoms of the ZnCl42- tetrahedron are acting as acceptors of hydrogen bonds. The crystal packing is influenced by cation-to-anion N-H…Cl and C-H…Cl hydrogen bonds leading to open framework architecture.

Diaqua­bis­(perchlorato)(1,10-phenanthroline)copper(II)

In the title compound, [Cu(ClO4)2(C12H8N2)(H2O)2], the CuII atom is coordinated in a square-planar fashion by the two N atoms of a chelating 1,10-phenanthroline ligand and by two water molecules trans to the N atoms. The coordination sphere of the metal atom is augmented by O atoms of two weakly bonded perchlorate anions, thus yielding a strongly distorted CuN2O4 octahedral environment. The crystal packing is stabilized by O—H⋯O hydrogen bonds between the water molecules and the perchlorate anions. In addition, the organic molecules are associated by π–π stacking interactions between symmetry-equivalent antiparallel non-nitrogen aromatic rings, with interplanar distances of 3.543 (2) Å.

Physico-Chemical Studies of Tris (adamantan-1-aminium) Hexachlorostannate (IV) Chloride Monohydrate

The structural characteristics of organic ammonium salts of the hexahalogenostannates (IV) with a general formula (R-NH 3)3SnX 6 have not yet been studied extensively. In the course of investigating these types of materials, the title compound, a double salt of adamantan-1aminium chloride and hexahalogenostannate (IV), with the formula (C 10 H18 N) 3[SnCl 6]Cl·H 2O, was crystallized. Its asymmetric unit contains three independent cations of protonated adamantan-1-amine, one chloride anion, one Hexachlorostannate (IV) ion and a hydrate water molecule. The atomic arrangement can be described as inorganic SnCl 6 2- units isolated from each other by the organic cations, the chloride anions and the cocrystallized water molecules. The compound exhibits bifurcated and simple hydrogenbonding interactions between the ammonium groups, the water molecules and the chlorine atoms, with little variation in the hydrogen-bonding interactions. The 119 Sn, 13 C and 15 N CPMAS NMR spectra are in agreement with the X-ray structure.

o-Phenyl-enediaminium chloride nitrate.

In the title molecular salt, C6H10N2 2+·NO3 −·Cl−, the complete cation is generated by a crystallographic mirror plane. The complete nitrate ion is also generated by reflection, with the N atom and one O atom lying on the mirror plane; the chloride ion also lies on the reflection plane. In the crystal, the components are linked by N—H⋯Cl and N—H⋯(N,O) hydrogen bonds, forming (001) layers with the benzene rings projecting into the interlayer regions. The layers are linked by weak C—H⋯O hydrogen bonds, generating a three-dimensional network.

Tris(5-amino-1H-1,2,4-triazol-4-ium) dihydrogenphosphate hydrogen­phosphate trihydrate

In the crystal structure of the title molecular salt, 3C2H5N4 +·HPO4 2−·H2PO4 −·3H2O, the phosphate-based framework is built upon layers parallel to (010) made up from the H2PO4 − and HPO4 2− anions and water molecules, which are interconnected through O—H⋯O hydrogen bonds. The organic cations are located between the phosphate–water layers and are connected to them via N—H⋯O hydrogen bonds. The bond-length features are consistent with an imino resonance form for the exocyclic amino group, as is commonly found for a C—N single bond involving sp 2-hybridized C and N atoms.

Bis(2-amino-5-chloro­pyridinium) tetra­chloridozincate

The asymmetric unit of the title compound, (C5H6ClN2)2[ZnCl4], contains two 2-amino-5-chloropyridinium cations and one [ZnCl4]2− dianion which are held together by N—H⋯Cl and C—H⋯Cl hydrogen bonds. The [ZnCl4]2− anions have a distorted tetrahedral geometry. Weak intermolecular π–π stacking interactions exist between neighbouring aromatic rings of the cations with a centroid–centroid distance of 3.712 (7) Å.

Piperazinediium tetra­chloridocadmate monohydrate

In the title compound, (C4H12N2)[CdCl4]·H2O, the [CdCl4]2− anions adopt a slightly distorted tetrahedral configuration. In the crystal, O—H⋯Cl hydrogen bonds link the anions and water molecules into corrugated inorganic chains along the b axis which are interconnected via piperazinediiumN—H⋯O and N—H⋯Cl interactions into a three-dimensional framework structure.