Search results for "stacking"
showing 10 items of 215 documents
Tris(1,10-phenanthroline-κ2N,N′)nickel(II) bis(hexafluoridophosphate)
2018
The asymmetric unit of the title compound, [Ni(C36H24N6)3](PF6)2, contains one and a half nickel(II) complex dications and three hexafluoridophosphate anions, one of the dications having crystallographic twofold rotational symmetry. Each NiIIatom displays a distorted octahedral coordination geometry provided by the six N atoms of three bidentate 1,10-phenanthroline ligands with bite angles of 79.68 (11)–80.76 (12)°. In the crystal, C—H...F hydrogen bonds link the anions and dications into a three-dimensional supramolecular framework. Within the framework complex dications with twofold rotational symmetry are linked by weak π–π stacking interactions [centroid-to-centroid distances = 3.712 (2…
Intramolecular 1,5-S...N σ-hole interaction in (E)-N′-(pyridin-4-ylmethylidene)thiophene-2-carbohydrazide
2020
The hydrazide-hydrazone forms inverse dimers via hydrogen bonding, but its conformation is defined by the presence of an intramolecular chalcogen bond. Electrostatic forces dominate in the crystal packing and give rise to a layered supramolecular structure.
2-(3-Methyl-2-oxo-1,2-dihydroquinoxalin-1-yl)acetic acid dihydrate
2018
In the title compound, C11H10N2O3·2H2O, the constituent atoms of the dihydroquinoxaline moiety deviate from the mean plane of the unit by +0.0572 (8) to −0.0874 (8) Å while the acetic acid substituent is nearly orthogonal to this plane. The crystal packing consists of corrugated layers constructed by O—H...O, O—H...N and C—H...O hydrogen bonds, which also involve the lattice water molecules. O—H...O hydrogen bonds and π–π stacking interactions hold these layers together.
Substituent effects in nitro derivatives of carbazoles investigated by comparison of low-temperature crystallographic studies with density functional…
2014
The crystal structure of 9H-carbazole, C12H9N, (I), has been redetermined at low temperature for use as a reference structure in a comparative study with the structures of 1-nitro-9H-carbazole, C12H8N2O2, (II), and 9-nitrocarbazole, C12H8N2O2, (III). The molecule of (I) has crystallographically imposed mirror symmetry (Z′ = 0.5). All three solid-state structures are slightly nonplanar, the dihedral angles between the planes of the arene and pyrrole rings ranging from 0.40 (7)° in (III) to 1.82 (18)° in (II). Nevertheless, a density functional theory (DFT) study predicts completely planar conformations for the isolated molecules. To estimate the influence of nitro-group substitution on aroma…
Crystal structures of allyltriphenyl-phosphonium halogenocuprates(I)
2013
Alternating-current electrochemical synthesis is used to obtain for the first time halogenocuprates of an allyl derivative of phosphonium of the composition (CH2=CHCH2(C6H5)3P)CuX2 (X = Br (I), Cl (II)). Compound I crystallizes in the space group P21, a = 9.6341(3) A, b = 12.4167(4) A, c = 9.9618(4) A, β = 117.484(5)°, Z = 2. Compound II crystallizes in the space group P21/n, a = 9.9725(5) A, b = 15.4586(8) A, c = 13.7557(5) A, β = 90.429(4)°, Z = 4. In the structures of I and II quasilinear CuX 2 − anions are held by C-H…X hydrogen bonds inside a framework formed by the stacking of phenyl groups from CH2=CHCH2(C6P5)3P+ cations. Allyl groups are not involved in coordination with copper(I) a…
Azonia spiro polyaza macrocycles containing biphenyl subunits as anion and cation receptors
2011
Abstract The reaction of N-Boc triprotected cyclam with bis(chloromethyl)biphenyl followed by the corresponding deprotection of the nitrogen atoms allows the preparation of receptor 3 containing an azonia spiro subunit. This receptor shows slightly increased basicity than cyclam, in particular for the formation of the appropriate triply charged species as a consequence of the reduced capacity of the structure present in 3 to stabilize the species with lower protonation degrees through the formation of intramolecular hydrogen bonds. The properties of 3 as a receptor for Cu2+ and Zn2+ and the anions derived from PO 4 3 − ( Pi ) , P 2 O 7 4 − ( PPi ) , P 3 O 10 5 − ( TPP ) and ATP have been st…
The enrichment ratio of atomic contacts in crystals, an indicator derived from the Hirshfeld surface analysis
2014
An enrichment ratio is derived from the decomposition of the crystal contact surface between pairs of interacting chemical species. The propensity of different contact types to form is investigated.
Crystal structure of a 1:1 salt of 4-aminobenzoic acid (vitamin B10) with pyrazinoic acid
2018
The paper reports the crystal structure of novel salt of 4-aminobenzoic acid (Vitamin B10) with pyrazinoic acid.
2,3-Diphenylmaleimide 1-methylpyrrolidin-2-one monosolvate
2014
In the title compound, C16H11NO2·C5H9NO, the dihedral angles between the maleimide and phenyl rings are 34.7 (2) and 64.8 (2)°. In the crystal, the 2,3-diphenylmaleimide and 1-methylpyrrolidin-2-one molecules form centrosymmetrical dimersviapairs of strong N—H...O hydrogen bonds and π–π stacking interactions between the two neighboring maleimide rings [centroid–centroid distance = 3.495 (2) Å]. The dimers are further linked by weak C—H...O and C—H...π hydrogen bonds into a three-dimensional framework.
6-Amino-2-(pivaloylamino)pyridinium benzoate
2013
In the crystal structure of the title salt, C10H16N3O+·C7H5O2−, the cations and anions are linked to each other via N—H⋯O hydrogen bonds, forming infinite chains running along [010]. The crystal structure also features C—H⋯O and π–π stacking interactions, which assemble the chains into supramolecular layers parallel to (100). The π–π stacking interactions are observed between the pyridine rings of inversion-related cations with a centroid–centroid distance of 3.867 (2) Å. Financial support from the National Science Centre in Kraków (grant No. NCN204 356840) is gratefully acknowledged. Academy Professor Kari Rissanen (Academy of Finland grant Nos. 122350, 140718, 265328 and 263256) and th…