C—H⋯O,C—H⋯π and π–π inter­actions in three benzofuran‐2‐yl ketone derivatives

The mol­ecules of 2‐benzoyl‐1‐benzofuran, C₁₅H₁₀O₂, (I), inter­act through double C—H⋯O hydrogen bonds, forming dimers that are further linked by C—H⋯O, C—H⋯π and π–π inter­actions, resulting in a three‐dimensional supramolecular network. The dihedral angle between the benzo­yl and benzofuran fragments in (I) is 46.15 (3)°. The mol­ecules of bis­(5‐bromo‐1‐benzofuran‐2‐yl) ketone, C₁₇H₈Br₂O₃, (II), exhibit C₂ symmetry, with the carbon­yl group (C=O) lying along the twofold rotation axis, and are linked by a combination of C—H⋯O and C—H⋯π inter­actions and Br⋯Br contacts to form sheets. The stability of the mol­ecular packing in 3‐mesit­yl‐3‐methyl­cyclo­but­yl 3‐methyl­naphtho[1,2‐b]furan‐2‐yl ketone, C₂₈H₂₈O₂, (III), arises from C—H⋯π and π–π stacking inter­actions. The fused naphthofuran moiety in (III) is essentially planar and makes a dihedral angle of 81.61 (3)° with the mean plane of the trimethyl­benzene ring.     

4‐Bromo‐2‐{[4‐(3‐mesityl‐3‐methyl­cyclo­butyl)thia­zol‐2‐yl]hydrazono­meth­yl}phenol,with N—H⋯N,C—H⋯π and π–π inter­actions

The title compound, C₂₄H₂₆BrN₃OS, crystallizes in the triclinic space group P, with two independent mol­ecules in the asymmetric unit. The mol­ecules adopt an E geometry about the azomethine C=N double bond. The structure is stabilized as dimers by N—H⋯N hydrogen bonding. C—H⋯π and π–π inter­actions are also effective in the crystal packing.     

Crystal engineering via C—H⋯F and C—H⋯π interactions in two substituted indoles

The crystal structures of 1‐(4‐fluoro­phenyl)‐2‐phenyl‐4,5,6,7‐tetra­hydro‐1H‐indole, C₂₀H₁₈FN, and 1‐(4‐fluoro­phenyl)‐6,6‐di­methyl‐2‐phenyl‐4,5,6,7‐tetra­hydro‐1H‐indole, C₂₂H₂₂FN, have been determined in order to study the role of `organic fluorine' in crystal engineering. These mol­ecules pack in the crystal structure via different types of molecular motifs utilizing weak C—H⋯F and C—H⋯π interactions.     

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.     

Supramolecular structures of 2‐chloro‐5‐methyl­phenol and 4‐chloro‐3‐methyl­phenol (chlorocresol)

The crystal structures of the title compounds (both C₇H₇ClO) are characterized by two independent mol­ecules in each of the asymmetric units and feature O—H...O, C—H...π and π–π interactions. In addition, intermolecular C—H...Cl and intramolecular O—H...Cl interactions are present in 2‐chloro‐5‐methyl­phenol. For each crystal, the non‐covalent interactions emphasize the different spatial environments for the two independent mol­ecules.     

Hydro­gen‐bonding and C—H⋯π interactions in 1,7‐bis(4‐hydroxy‐3‐methoxy­phenyl)­heptane‐3,5‐dione (tetra­hydro­curcumin)

The title compound, C₂₁H₂₄O₆, is the reduced form of curcumin, and exhibits important cosmoceutical properties. The mol­ecule is non‐planar and the benzene rings positioned at the ends of the heptane chain are orthogonally placed, with a dihedral angle of 84.09 (7)° between them. The molecular geometry and H‐atom locations reveal that the `heptane‐3,5‐dione' moiety exists in the keto–enol form, with the hydroxy H atom disordered over two adjacent sites. The packing of the mol­ecules in the lattice is directed by strong O—H⋯O intermolecular hydrogen bonds, which generate two‐dimensional sheets. These sheets are linked by C—H⋯O hydrogen bonds and weak C—H⋯π interactions to develop a three‐dimensional network.     

N—H⋯N and C—H⋯π inter­actions in 4‐amino‐3‐methyl‐5‐(p‐tol­yl)‐4H‐1,2,4‐triazole and 4‐amino‐3‐methyl‐5‐phenyl‐4H‐1,2,4‐triazole

The title compounds, C₁₀H₁₂N₄, (I), and C₉H₁₀N₄, (II), have been synthesized and characterized both spectroscopically and structurally. The dihedral angles between the triazole and benzene ring planes are 26.59 (9) and 42.34 (2)°, respectively. In (I), mol­ecules are linked principally by N—H⋯N hydrogen bonds involving the amino NH₂ group and a triazole N atom, forming R₄⁴(20) and R₂⁴(10) rings which link to give a three‐dimensional network of mol­ecules. The hydrogen bonding is supported by two different C—H⋯π inter­actions from the tolyl ring to either a triazole ring or a tolyl ring in neighboring mol­ecules. In (II), inter­molecular hydrogen bonds and C—H⋯π inter­actions produce R₃⁴(15) and R₄⁴(21) rings.     

Displaced π–π stacking and hydrogen bonds in 3‐bromo‐N‐(2‐hydroxy‐1,1‐di­methyl­ethyl)­benz­amide

The mol­ecules of the title compound, C₁₁H₁₄BrNO₂, are assembled into a two‐dimensional network by a combination of hydrogen bonds and stacking interactions. The phenyl rings are stacked along the c direction by displaced π–π interactions, forming a lipophilic layer. The aliphatic amide residues are interconnected along [100] by O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds, forming hydro­philic layers.     

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.     

O—H⋯O‐bridged dimers linked via C—H⋯O and C—H⋯π inter­actions in 4,6‐di‐O‐benzyl‐myo‐inositol 1,3,5‐orthoformate

The centrosymmetric O—H⋯O‐bonded head‐to‐head dimers of the title compound, C₂₁H₂₂O₆, are linked together via bifurcated C—H⋯O inter­actions along the a axis and via favourable C—H⋯π inter­actions along the b axis in the crystal structure.     

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.     

A mixed crystal of imperatorin and phellopterin,with C—H...O,C—H...π and π–π interactions

The crystal structure of 9‐(3‐methyl­but‐2‐enyl­oxy)­‐7H‐furo­[3,2‐g]­chro­men‐7‐one–4‐methoxy‐9‐(3‐methyl­but‐2‐enyl­oxy)‐7H‐­furo­[3,2‐g]­chromen‐7‐one (0.926/0.074), 0.926C₁₆H₁₄O₄·0.074C₁₇H₁₆O₅, is characterized by two independent imperatorin mol­ecules in the asymmetric unit, which exhibit different side‐chain conformations. A small amount of phellopterin overlaps with one of the two imperatorin mol­ecules. The supramol­ecular structure is supported by C—H...O, C—H...π and π–π interactions.     

4‐(4‐Chloro­benzyl­ideneamino)‐1,5‐dimethyl‐2‐phenyl‐1H‐pyrazol‐3(2H)‐one and 4‐(2‐chloro­benzyl­idene­amino)‐1,5‐dimethyl‐2‐phenyl‐1H‐pyrazol‐3(2H)‐one

The two title compounds, both with formula C₁₈H₁₆ClN₃O, are structurally similar Schiff bases derived from the condensation of 4‐chloro­benzaldehyde or 2‐chloro­benzaldehyde with 4‐amino­anti­pyrine in methanol solution. As expected, both compounds adopt trans configurations about the central C=N bonds. In the crystal structure of the 4‐chloro analogue, mol­ecules are linked through weak C—H⋯O hydrogen bonds, forming chains running along the a axis. In the crystal structure of the 2‐chloro analogue, mol­ecules are linked through weak C—H⋯O and C—H⋯Cl hydrogen bonds, forming layers parallel to the ab plane.     

Proton‐bifurcated C—H⋯(O,O) hydrogen bonds in 2,3‐dichloro‐6‐nitro­benzyl­aminium chloride

In the crystal structure of the title salt, C₇H₇Cl₂N₂O₂⁺·Cl⁻, the chloride anions participate in extensive hydrogen bonding with the aminium cations and indirectly link the mol­ecules through multiple N⁺—H⋯Cl⁻ salt bridges. There are two independent mol­ecules in the asymmetric unit, related by a pseudo‐inversion center. The direct inter­molecular coupling is established by C—H⋯O, C—H⋯Cl and C—Cl⋯Cl⁻ inter­actions. A rare three‐center (donor bifurcated) C—H⋯(O,O) hydrogen bond is observed between the methyl­ene and nitro groups, with a side‐on intra­molecular component of closed‐ring type and a head‐on inter­molecular component.     

1‐Benzyl‐3,3‐dichloro‐1H‐indol‐2(3H)‐one

The title compound, C₁₅H₁₁Cl₂NO, was synthesized from N‐­benzyl­isatin. The compound crystallizes as stacks of mol­ecules running down the c axis. Mol­ecules within each of these stacks inter­act with each other through π–π and C—H⋯π inter­actions, and inter­act with neighbouring stacks through C—H⋯O inter­actions.     

1‐(4‐Bromo­phenyl)‐3‐(4‐methyl­phenyl)­prop‐2‐en‐1‐one

In the mol­ecule of the title compound, C₁₆H₁₃BrO, the two benzene rings are rotated in opposite directions with respect to the central C—C=C—C part of the mol­ecule. The phenone O atom deviates from the least‐squares plane of the mol­ecule by 0.300 (3) Å. In the crystal structure, mol­ecules are paired through C—H⋯π interactions. The molecular pairs along [001] are hydrogen bonded through three translation‐related co‐operative hydrogen bonds in the `bay area', forming molecular chains, which are further hydrogen bonded through C—H⋯Br weak interactions, forming (010) molecular layers. In the third direction, there are only weak van der Waals interactions. The co‐operative hydrogen bonds in the `bay area' are discussed briefly.     

4,6‐Bis­(methyl­sulfanyl)‐1‐(4‐phenoxy­butyl)‐1H‐pyrazolo­[3,4‐d]­pyrimidine

The molecular structure of the title compound, C₁₇H₂₀N₄OS₂, does not show any intramolecular aromatic π–π interactions, but the crystal packing reveals the presence of intermolecular C—H...O and C—H...π interactions. The C—H...O interactions generate chains of mol­ecules that are linked into sheets by C—H...π interactions about inversion centres.     

3‐Methoxy‐5‐(4‐methyl­phenyl­diazenyl)­salicyl­aldehyde and 3‐methoxy‐5‐(2‐methyl­phenyl­diazenyl)­salicyl­aldehyde

The two title mol­ecules, both C₁₅H₁₄N₂O₃, are roughly planar and display a trans conformation with respect to the –N=N– double bond, as found for other diazene derivatives. In both compounds, there are intramolecular O—H⋯O hydrogen bonds and the crystal packing is governed by weak intermolecular C—H⋯O hydrogen bonds and π–π stacking.     

Naphthalene‐1,7‐diol

The asymmetric unit of the title compound, C₁₀H₈O₂, contains two planar symmetry‐independent mol­ecules linked by an O—H⋯O hydrogen bond. In the crystal structure, mol­ecules are linked into infinite chains of rings, formed by a combination of O—H⋯O and C—H⋯O hydrogen bonds, and additionally reinforced by π–π stacking inter­actions. Adjacent chains are connected by weak C—H⋯π inter­actions.     

Three‐dimensional aggregation in 2‐hydroxy‐3‐iodo‐5‐nitrobenzaldehyde involving C—H⋯O,iodo–nitro and aromatic π–π stacking interactions,and isolated dimers in disordered 2,4‐diiodo‐6‐nitroanisole

In 2‐hydroxy‐3‐iodo‐5‐nitro­benz­aldehyde, C₇H₄INO₄, the mol­ecules are linked into sheets by a combination of C—H⋯O hydrogen bonds and two‐centre iodo–nitro interactions, and these sheets are linked by aromatic π–π stacking interactions. Molecules of 2,4‐di­iodo‐6‐nitro­anisole, C₇H₅I₂NO₃, are disordered, with the nitro group and one of the I substituents each occupying common sets of sites with 0.5 occupancy. The mol­ecules are linked into isolated centrosymmetric dimeric units by a single iodo–nitro interaction.