Hydro­gen bonding and C—H⋯O interactions in 3‐(3‐amino­phthal­imido)phthalic acid dihydrate

The title compound, C₁₆H₁₀N₂O₆·2H₂O, crystallized in the centrosymmetric triclinic space group P with one organic mol­ecule and two water mol­ecules as the asymmetric unit. Eight intermolecular hydrogen bonds have donor?acceptor distances in the range 2.602 (2)–3.289 (2) Å, with angles in the range 137 (2)–177 (2)°. These generate a three‐dimensional hydrogen‐bond network. There is a single intramolecular hydrogen bond. There are six significant intermolecular C—H?O interactions with H?O distances in the range 2.39–2.74 Å, and C—H?O angles in the range 131–157°.     

An analysis of C—H⋯O and C—H⋯π interactions in three substituted 4‐ketotetra­hydro­indoles

The crystal and molecular structures of the three 4‐ketotetrahydro­indoles 2‐(4‐chloro­phenyl)‐1‐(4‐fluoro­phenyl)‐6,6‐dimethyl‐4,5,6,7‐tetra­hydro‐1H‐indol‐4‐one (C₂₂H₁₉ClFNO), (I), 1‐(4‐fluoro­phenyl)‐2‐(4‐methoxy­phenyl)‐6,6‐di­methyl‐4,5,6,7‐tetra­hydro‐1H‐indol‐4‐one (C₂₃H₂₂FNO₂), (II), and 6,6‐dimethyl‐1,2‐di­phenyl‐4,5,6,7‐tetra­hydro‐1H‐indol‐4‐one (C₂₂H₂₁NO), (III), have been determined via single‐crystal X‐ray diffraction in order to study the intermolecular interactions therein. All three structures are stabilized via intermolecular C—H⋯O and C—H⋯π interactions, generating different molecular motifs.     

Hydro­gen bonds and C—H⋯O ­interactions in the enol tautomer of 4‐­(phenylsulfonyl)spiro­[cyclo­pentane‐1,9′‐[9H]­fluorene]‐2,3‐dione

The title compound, 2‐hydroxy‐1‐(phenyl­sulfonyl)­spiro­[cyclo­pentene‐4,9′‐[9H]­fluoren]‐3‐one, C₂₃H₁₆O₄S, crystallized in the centrosymmetric space group P2₁/n with one mol­ecule as the asymmetric unit. The hydroxyl‐H atom is ordered and participates in a single intramolecular hydrogen bond and in a single intermolecular hydrogen bond, in which the O_D—H distance is 0.90 (2), H?O_A is 2.34 (3), O_D?O_A is 2.987 (2) Å and O_D—H?O_A is 129 (2)°. The intermolecular hydrogen bond forms an R(12) cyclic dimer about a center of symmetry. There are six leading C—H?O interactions. Taken together, these interactions form a three‐dimensional network. Structural comparisons are made with tetrabenzodi­spiro­[4.0.4.3]­tridecatetraene.     

(E)‐1‐(2‐Hydro­xy‐4‐methoxy­phenyl)‐2‐(3,4,5‐tri­methoxy­phenyl)­ethene

In the crystal structure of the title compound, C₁₈H₂₀O₅, all geometric parameters fall within experimental error of the expected values. Analysis of the molecular‐packing plots reveals an infinite one‐dimensional linear array running parallel to the c axis, formed by an O—H⃛O intermolecular hydrogen‐bonding interaction. The stilbene framework and most of the substituents are approximately coplanar.     

3,3‐Bis(2‐methoxy­phenyl)‐3H‐benzo­[f]­chromene

The substituent methoxy group at the phenyl ortho position in the title compound, C₂₇H₂₂O₃, has an insignificant effect on the length of the Csp³—O bond and on the non‐planarity of the pyran ring. The cause of the changes in the photochemical properties is discussed.     

2‐Hydro­xy‐5‐[(E)‐(4‐methoxy­phenyl)­diazenyl]­benzoic acid

The title compound, C₁₄H₁₂N₂O₄, shows an E conformation about the diazenyl N atoms. The crystal structure features layers of mol­ecules with the primary connection between the layers afforded by carboxyl­ic acid dimer motifs; no evidence for extensive π–π stacking between the layers was found.     

trans‐Dichloro­tetra­benzimidazole­cadmium(II) tetra­benzimidazole: a three‐dimensional supra­molecular structure built from C—H⋯π, N—H⋯Cl and N—H⋯N hydrogen bonds

The title compound, [CdCl₂(C₇H₆N₂)₄]·4C₇H₆N₂, consists of a Cd(Bzim)₄Cl₂ complex (Bzim is benzimidazole) lying on a fourfold rotation axis in the space group P4nc, and four benzimidazole mol­ecules which are linked to the coordinated benzimidazole unit by N—H⋯N hydrogen bonds. One N—H⋯Cl and three C—H⋯π hydrogen bonds link these units into a three‐dimensional supra­molecular structure.     

Red,orange and yellow crystals of 4,5‐­bis(4‐methoxy­phenyl)‐2‐(3‐nitro­phenyl)‐1H‐imidazole

Red non‐solvate crystals of the title compound from ethanol, C₂₃H₁₉N₃O₄, orange solvate crystals from tert‐butanol, C₂₃H₁₉N₃O₄·C₄H₁₀O, yellow solvate crystals from dioxane–water, C₂₃H₁₉N₃O₄·0.5C₄H₈O₂, and intense yellow solvate crystals from benzene–N,N′‐dimethylformamide, C₂₃H₁₉N₃O₄·C₆H₆, differ from each other in their molecular conformation and hydrogen‐bonding scheme. The bathochromic shifts of the crystal color are explained by the molecular planarity and charge‐transfer effect among the imidazole mol­ecules.     

C—H⋯N and C—H⋯π interactions in 2‐ethoxy‐4,6‐diphenylpyridine‐3‐carbonitrile

The title compound, C₂₀H₁₆N₂O, has two mol­ecules in the asymmetric unit and the crystal structure shows that the central pyridine ring of each mol­ecule has a flat boat conformation. The terminal C atom in one of the mol­ecules is disordered over two positions, with relative occupancies of 0.594 (14) and 0.398 (14). Intermolecular C—H?N and C—H?π interactions and π–π stacking, along with intramolecular C—H?N and C—H?π interactions, help to stabilize the structure.     

Hydro­gen bonding and C—H⋯X interactions in 3‐fluoro‐2‐[1‐(1‐naph­thyl)ethyl]benzoic acid

The title acid, C₁₉H₁₅FO₂, crystallized in the centrosymmetric space group P with one mol­ecule as the asymmetric unit. There is a single hydrogen bond, with an O_D?O_A distance of 2.632 (2) Å and an O_D—H?O_A angle of 177 (3)°, which forms an R(8) cyclic dimer about a center of symmetry. There is a single leading intermolecular C—H?X interaction, with an H?F distance of 2.49 Å and a C—H?F angle of 147°. Three leading intramolecular C—H?X interactions appear to play a significant role in determining the orientation of the methyl and carboxyl groups.     

5‐[N‐(1H‐Benzotriazol‐1‐yl­methyl)­amino]‐3‐tert‐butyl‐1‐phenyl­pyrazole: sheets built from N—H⋯N,C—H⋯N and C—H⋯π(pyrazole) interactions

In the title compound, C₂₀H₂₂N₆, the mol­ecules are linked into a chain of rings by N—H?N [H?N 2.16 Å, N?N 2.950 (3) Å and N—H?N 149°] and C—H?N [H?N 2.55 Å, C?N 3.481 (3) Å and C—H?N 165°] hydrogen bonds, and these chains are linked into sheets by means of C—­H?π(pyrazole) interactions.     

1‐(2‐Hydro­xy‐4‐methoxy­phenyl)‐3‐(2,3,4‐tri­methoxy­phenyl)­prop‐2‐en‐1‐one

The title compound, C₁₉H₂₀O₆, crystallizes in the centrosymmetric space group P2₁/c with one mol­ecule in the asymmetric unit. The mol­ecule is approximately planar and the dihedral angle between the phenyl rings is 11.0 (1)°. The H atoms of the central propenone group are trans. There is an intramolecular O—H⃛O hydrogen bond and the mol­ecules are crosslinked by four intermolecular C—H⃛O hydrogen bonds, producing a three‐dimensional network.     

Hydro­gen bonds and C—H⋯O interactions in 2‐(2‐methyl­benzyl)­malonic acid at 150 K

The title compound, C₁₁H₁₂O₄, crystallized in the centrosymmetric space group Pbca with one mol­ecule as the asymmetric unit. The two hydrogen bonds have O_D?O_A distances of 2.667 (2) and 2.628 (2) Å, and O—H?O angles of 179 (2) and 177 (2)°. Each hydrogen bond forms an R(8) cyclic dimer about a center of symmetry. The leading intermolecular C—­H?O interaction has an H?O distance of 2.66 Å and a C—H?O angle of 160°. Taken together with the hydrogen bonds, it results in a three‐dimensional network of inter­actions. The structure is compared with that of a close analog, benzyl­malonic acid.     

Tetrakis­(tetra­hydro­furan‐κO)­lithium mer‐tris­(carbazolyl‐κN)‐trans‐di­chloro(tetra­hydro­furan‐κO)­zirconate

In the title compound, [Li(C₄H₈O)₄][ZrCl₂(C₁₂H₈N)₃(C₄H₈O)], the environment of the Zr atom is pseudo‐octahedral, with the three carbazolyl ligands in a mer configuration. The counter‐ion of the zirconium complex is composed of an Li atom surrounded by four tetra­hydro­furan (THF) mol­ecules. The THF mol­ecule attached to the Zr atom is disordered over two sites, as are two of the THF mol­ecules in the lithium moiety. All bond distances and angles are consistent with those in complexes with similar structural entities. The Zr—N bond distances are 2.2185 (18) and 2.167 (3) Å.     

Hydro­gen‐bonded molecular ladders in trans‐1,2‐bis(2‐nitro­anilino)­cyclo­hexane

Crystals of the title compound, C₁₈H₂₀N₄O₄, contain equal numbers of (R,R) and (S,S) mol­ecules, but these are not precise enantiomorphs, neither are they related by crystallographic symmetry; in addition, each mol­ecule exhibits approximate, but not exact, twofold rotational symmetry. There are intramolecular N—H?O hydrogen bonds [N?O 2.609 (4)–2.638 (5) Å; N—H?O 125–132°] and the mol­ecules are linked into molecular ladders by C—H?O hydrogen bonds [C?O 3.306 (6)–3.386 (6) Å; C—H?O 146–160°].     

H⋯Br hydrogen bonding in trans‐bis(acetonitrile‐N)tetraaquacobalt(II) dibromide

In the title complex, [Co(CH₃CN)₂(H₂O)₄]Br₂, the Co^II atom lies on an inversion centre and is octahedrally coordinated by two trans acetonitrile molecules and four water molecules. Hydrogen bonding between the water molecules and lattice bromide ions yields a three‐dimensional structure.     

Hydro­gen‐bonding patterns in two structural isomers of 3,6‐bis(2‐chloro­phenyl)‐1,4‐di­hydro‐1,2,4,5‐tetrazine

Two structural isomers, 3,6‐bis(2‐chloro­phenyl)‐1,4‐di­hydro‐1,2,4,5‐tetrazine, (I), and 3,5‐bis(2‐chloro­phenyl)‐4‐amino‐1H‐1,2,4‐triazole, (II), both C₁₄H₁₀Cl₂N₄, form chain‐like structures in the solid state, stabilized by N—H⋯N and N—H⋯Cl hydrogen bonds. A contribution from weak interactions to the strong hydrogen‐bond network is observed in both structures. The secondary graph sets for intermolecular hydrogen bonds [(11) for (I) and (12) for (II)] indicate the similarity between the networks.     

2′,4′‐Di­hydroxy‐3‐methoxy‐α,β‐di­hydro­chalcone and 2′,4‐di­hydroxy‐α,β‐di­hydro­chalcone: supramolecular structures formed by O—H⋯O,C—H⋯O and stacking interactions

The crystal structures of 2′,4′‐di­hydroxy‐3‐methoxy‐α,β‐di­hydro­chalcone, C₁₆H₁₆O₄, and 2′,4‐di­hydroxy‐α,β‐di­hydro­chalcone, C₁₅H₁₄O₃, have been determined. In both compounds, the structure consists of two nearly planar six‐membered aromatic rings connected by a propanal chain, which is bent in the methoxy compound and almost straight in the other compound. In the crystal structures, the molecular units of both compounds are linked by O—H⋯O hydrogen bonds to form infinite one‐dimensional chains. Hydro­gen bonds and C—H⋯O contacts in the crystal structures were studied by topological analysis of charge density based on Hartree–Fock calculations. Almost all of the investigated C—H⋯O contacts should be characterized as weak hydrogen bonds.     

C—H⋯π, π–π and C—H⋯Cl interactions in chloro‐substituted Schiff bases and 4‐chloro‐N‐[4‐(di­methyl­amino)­benzyl­idene]­aniline

Molecular packing analyses were carried out on 15 crystal data sets of chloro‐substituted Schiff bases, including that of the title compound, C₁₅H₁₅ClN₂. C—H⋯π and π–π interactions play a major role in the molecular self‐assembly in the crystal. The former interactions favor mol­ecules assembling into a screw, with a non‐centrosymmetric crystal structure. When the molecular dipole is small, π–π interactions favor a parallel, but not usually antiparallel, mode of packing. Weak C—H⋯X hydrogen bonds (X = Cl or Br) and X⋯X interactions seem to be a secondary driving force in packing. The title mol­ecule takes the trans form and the two benzene rings are twisted around the central linkage in opposite directions. In the crystal structure, mol­ecules interact through C—H⋯π and π–π interactions, forming a `dimer' and further forming double chains along [001]. The double chains are extended along [10] through C—H⋯Cl hydrogen bonds, forming double layers in (010). In the third direction, there are only ordinary, weaker, van der Waals interactions, which explains the crystal habit (i.e. thin plate).