In the title compound, C19H17NO2, the dihedral angle between the benzene ring and the naphthalene ring system is 9.72 (5)°, while the torsion angle of the C—N—C—C bridging group is 179.24 (17)°. The methyl group of the 1-phenylethanol moiety is disordered over two positions with a refined occupancy ratio of 0.775 (5):0.225 (5). The molecular conformation is stabilized by an intramolecular N—H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, molecules are linked by O—H⋯O hydrogen bonds, forming zigzag chains propagating along the c-axis direction. Neighbouring chains are linked via C—H⋯O interactions, forming a two-dimensional slab-like network parallel to the bc plane.
The central residue in the title compound, C21H21N3O3, is close to planar (r.m.s. deviation = 0.0753 Å for all non-H atoms from OH to NH inclusive): the hydroxy, amino and carbonyl groups all lie to the same side of the molecule (the conformation about the ethene bond is Z), facilitating the formation of intramolecular O—H⋯O and N—H⋯O hydrogen bonds that close S(6) rings. However, overall the molecule is twisted as the terminal aromatic rings are not coplanar with the central plane [dihedral angles = 20.55 (5) and 80.90 (4)° for the N-bound phenyl ring and the methoxybenzene ring, respectively]. The dihedral angle between the rings is 82.14 (7)°. Supramolecular layers in the ac plane mediated by C—H⋯π interactions are found in the crystal.
In the solid state, the title compound, adopts the keto–amine tautomeric form, with the H atom attached to the N atom, which participates in an intramolecular N—H⋯O hydrogen bond with an S(6) ring motif. In the crystal, molecules are linked by weak C—H⋯O hydrogen bonds to generate C(16) chains propagating in the  direction.
In the solid state, the title compound, C20H19N3O2, adopts the keto–amine tautomeric form, with the H atom attached to the N atom, which participates in an intramolecular N—H⋯O hydrogen bond with an S(6) ring motif. The dihedral angles between the pyrazole ring and the phenyl and benzene rings are 3.69 (10) and 46.47 (9)°, respectively. In the crystal, molecules are linked by weak C—H⋯O hydrogen bonds, generating C(16) chains propagating in . Weak aromatic π–π stacking interactions [centroid–centroid distances = 3.6123 (10) and 3.6665 (10) Å] link the chains into a three-dimensional network.
crystal structure; Schiff bases; pyrazolone derivatives; keto–amine tautomeric form; hydrogen bonding; π–π stacking interactions
A series of N-(2-phenylethyl)nitroaniline derivatives is presented, demonstrating that modest changes in the functional groups cause significant differences in molecular conformation, intermolecular interactions and packing.
2,4-Dinitro-N-(2-phenylethyl)aniline, C14H13N3O4, (I), crystallizes with one independent molecule in the asymmetric unit. The adjacent amine and nitro groups form an intramolecular N—H⋯O hydrogen bond. The anti conformation about the ethyl C—C bond leads to the phenyl and aniline rings being essentially parallel. Molecules are linked into dimers by intermolecular N—H⋯O hydrogen bonds, such that each amine H atom participates in a three-centre interaction with two nitro O atoms. Though the dimers pack so that the arene rings of adjacent molecules are parallel, the rings are staggered and π–π interactions do not appear to be favoured. 4,6-Dinitro-N,N′-bis(2-phenylethyl)benzene-1,3-diamine, C22H22N4O4, (II), differs from (I) in the presence of a second 2-phenylethylamine group on the substituted ring. Compound (II) also crystallizes with one unique molecule in the asymmetric unit. Both amine groups are involved in intramolecular N—H⋯O hydrogen bonds with adjacent nitro groups. Although one ethyl group adopts an anti conformation as in (I), the other is gauche, with the result that the pendant phenyl rings are not parallel. The amine group that is part of the gauche conformation participates in a three-centre N—H⋯O hydrogen bond with the nitro group of a neighbouring molecule, leading to dimers as in (I). The other amine H atom does not form any intermolecular hydrogen bonds. The packing leads to separations of ca 3.4 Å of the parallel anti phenyl and aminobenzene rings. 2-Cyano-4-nitro-N-(2-phenylethyl)aniline, C15H13N3O2, (III), differs from (I) only in having a cyano group in place of the 2-nitro group. The absence of the adjacent nitro group eliminates the intramolecular N—H⋯O hydrogen bond. Molecules of (III) adopt the same anti conformation about the ethyl group as in (I), but crystallize in the higher-symmetry monoclinic space group P21/n. The molecules are linked into dimers via N—H⋯N amine–cyano hydrogen bonds, while the nitro groups are not involved in any N—H⋯O interactions. Owing to the different symmetry, the molecules pack in a herringbone pattern with fewer face-to-face interactions between the rings. The closest such interactions are about 3.5 Å between rings that are largely slipped past one another. 4-Methylsulfonyl-2-nitro-N-(2-phenylethyl)aniline, C15H16N2O4S, (IV), differs from (I) in having a methylsulfonyl group in place of the 4-nitro group. The intramolecular N—H⋯O hydrogen bond is present as in (I). However, unlike (I), the conformation about the ethyl group is gauche, so the two arene rings are nearly perpendicular rather than parallel. The packing is significantly different from the other three structures in that there are no intermolecular hydrogen bonds involving the N—H groups. The molecules are arranged in tetragonal columns running along the c axis, with the aniline rings mostly parallel and separated by ca 3.7 Å. Taken together, these structures demonstrate that modest changes in functional groups cause significant differences in molecular conformation, intermolecular interactions and packing.
crystal structure; N-(2-phenylethyl)nitroaniline derivatives; secondary amines; nitric oxide release agents
In the title compound, C20H19N3OS, the central benzene ring makes dihedral angles of 45.36 (9) and 55.33 (9)° with the thiophene ring and the dimethyl-substituted benzene ring, respectively. The dihedral angle between the thiophene ring and dimethyl-substituted benzene ring is 83.60 (9)°. The thiophene ring and the benzene ring are twisted from the mean plane of the C(=O)—N—N=C bridge [maximum deviation = 0.0860 (13) Å], with dihedral angles of 23.86 (9) and 24.77 (8)°, respectively. An intramolecular N—H⋯O hydrogen bond generates an S(6) ring. In the crystal, molecules are linked by N—H⋯O and C—H⋯O hydrogen bonds to the same acceptor atom, forming sheets lying parallel to the bc plane. The crystal packing also features C—H⋯π interactions.
The title compound, C26H23F3N4O, crystallizes with two symmetry-independent molecules in the asymmetric unit, denoted A and B, which differ mainly in the rotation of the methoxyphenyl ring. The –CF3 group of molecule B is disordered by rotation, with the F atoms split over two sets of sites; the occupancy factor for the major component is 0.853 (4). The dihedral angles between the pyrimidine ring and the attached phenyl, methoxyphenyl and trifluoromethylphenyl rings are 8.1 (2), 37.5 (2) and 70.7 (2)°, respectively, in molecule A, and 9.3 (2), 5.3 (2) and 79.7 (2)° in molecule B. An intramolecular N—H⋯N hydrogen bond occurs in each molecule. In the crystal, two crystallographically independent molecules associate into a dimer via a pair of N—H⋯N hydrogen bonds, with a resulting R
2(12) ring motif and π–π stacking interactions [centroid–centroid distance = 3.517 (4) Å] between the pyrimidine rings. For the A molecules, there are intermolecular C—H⋯O hydrogen bonds between an aryl C atom of methoxyphenyl ring and a methoxy O atom of an adjacent molecule. A similar interaction is lacking in the B molecules.
In the title compound, C19H15N3O3, the anilino and benzamide rings make dihedral angles of 10.66 (16) and 50.39 (16)°, respectively, with the nitro-substituted benzene ring. The nitro group is slightly twisted by 11.49 (17)° with respect to the attached benzene ring. There is an intramolecular N—H⋯O hydrogen bond forming an S(6) ring. In the crystal, weak intermolecular N—H⋯O and C—H⋯O hydrogen bonds link the molecules into a chain parallel to the b axis. Futhermore, weak slipped π–π interactions [centroid–centroid distance = 3.819 (2) Å, interplanar distance = 3.567 Å and offset angle [how is the offset angle defined?] = 21°] between the anilino ring and its symmetry-related counterpart may help to stabilize the packing.
In the title compound, C15H17N3O, the dihedral angle between the benzene rings is 58.05 (9)°. The non-H atoms of the hydrazide group lie in a common plane (r.m.s. deviation = 0.0006 Å) and are close to coplanar with their attached benzene ring [dihedral angle = 8.02 (9)°]. An intramolecular N—H⋯O hydrogen bond generates an S(6) ring motif in the molecule, and a short intramolecular contact (H⋯H = 1.88 Å) is also observed. In the crystal, molecules are linked by pairs of N—H⋯N hydrogen bonds into inversion dimers. The crystal packing also features C—H⋯π interactions.
In the title compound, C20H16BrFN4O3, the pyrimidine and 2-bromo-4-fluorophenyl rings are twisted away from the central benzene ring, making dihedral angles of 77.7 (1) and 85.5 (1), respectively. A pair of C—H⋯F interactions is involved in an R
2(8) motif, linking the molecules into dimers. These ring motifs are situated about the crystallographic centres of symmetry. C—H⋯O hydrogen bonds link the dimers into chains running parallel to . Additionally, a weak C—F⋯π-electron ring interaction was observed in the crystal packing [F⋯Cg = 3.459 (4) Å; Cg is the centroid of the pyrimidine ring]. There is also an intramolecular N—H⋯Br interaction in the structure.
In the title compound, C13H9N3O2, the aromatic rings are twisted with respect to each other, making a dihedral angle of 49.41 (9)°. The nitro group and the nitrile group are nearly in the plane of the benzonitrile ring, the largest deviation from the plane being 0.123 (1) Å. There is an intramolecular N—H⋯O hydrogen bond forming an S(6) ring. Weak intermolecular C—H⋯O hydrogen bonds link the molecules into a chain parallel to the c axis. Futhermore, slipped π–π interactions between symmetry-related phenyl rings [centroid–centroid distance 3.808 (1) Å, interplanar distance 3.544 (8) Å with an offset of 21.5°] stabilize the structure.
In the title compound, C25H23FN4, the pyrimidine ring makes dihedral angles of 11.3 (2), 24.5 (2) and 70.1 (2)° with the phenyl and two benzene rings, and the molecular conformation is stabilized by an intramolecular N—H⋯N hydrogen bond with an S(6) ring motif. In the crystal, a pair of weak C—H⋯F hydrogen bonds link two molecules into an inversion dimer with an R
2(16) motif. In the dimer, there is also an intermolecular π–π stacking interaction [centroid–centroid distance = 3.708 (4) Å] between the fluorinated benzene rings. The dimers are further linked by a C—H⋯π interaction, so forming a column along the c axis.
In the title compound, C24H18Cl4N4, the pyrimidine ring makes dihedral angles of 19.1 (2), 4.1 (2) and 67.5 (2)°, respectively, with phenyl and two benzene rings, and the molecular conformation is stabilized by an intramolecular N—H⋯N hydrogen bond closing a six-membered ring with an S(6) motif. In the crystal, a pair of intermolecular N—H⋯N hydrogen bonds connect two molecules, forming inversion dimers with R
2(12) motifs. C—H⋯π interactions links the dimers into a chain running along the a-axis direction. There are also π–π stacking interactions [centroid–centroid distance = 3.666 (4) Å] between the benzene rings of adjacent chains.
The molecule of the title compound, C26H24N4O7S, adopts a trans conformation about the central N—N bond, presumably to minimize steric between the substituents on these two atoms. An intramolecular N—H⋯O hydrogen bond occurs. The phenyl ring is disordered over two sets of sites, with an occupancy ratio of 0.624 (8):0.376 (8). The azolidine ring is essentially planar [maximum deviation = 0.008 (5) Å] and makes a dihedral angle of 4.3 (2)° with the benzene ring and dihedral angles of 74.1 (3) and 69.1 (5)°, respectively, with the mean planes of the major and minor components of the disordered phenyl ring. The packing in the crystal is aided by the formation of several weak C—H⋯O and C—H⋯N interactions.
In the title compound, C15H17NO, the 2,3-dimethylphenyl group is disordered over two sites with an occupancy ratio of 0.869 (3):0.131 (3). The major and minor components of the 2,3-dimethylanilino group are planar, with r.m.s. deviations of 0.0214 and 0.0303 Å, respectively, and are oriented at a dihedral angle of 2.6 (6)°. The phenylmethanol–benzene ring is oriented at dihedral angles of 83.16 (6) and 81.0 (3)° with respect to the major and minor components of the 2,3-dimethylanilino group, respectively. An S(6) ring motif is present due to intramolecular N—H⋯O hydrogen bonding. In the crystal, molecules are connected into supramolecular chains via O—H⋯O hydrogen bonding along the b axis. C—H⋯π interactions help to stabilize the crystal structure.
The asymmetric unit of the title compound, C6H5Cl2N·2C11H11Cl2NO, is composed of one molecule of an enamino–ketone [i.e. –(2,6-dichlorophenylamino)pent-3-en-2-one] and half a molecule of 2,6-dichloroaniline, the whole molecule of the latter component being generated by twofold rotational symmetry. In this latter molecule, there are two intramolecular N—H⋯Cl contacts. In the enamino–ketone molecule, there is an N—H⋯O hydrogen bond of moderate strength, and the dihedral angle between the benzene ring and pentanone fragment [C—C(—N)=C—C(=O)—C; planar within 0.005 (1) Å] is 81.85 (7)°. In the crystal, two molecules of the enamino–ketone are bridged by a molecule of 2,6-dichloroaniline via N—H⋯O hydrogen bonds of moderate strength. There are also π–π interactions present, involving the benzene rings of inversion-related enamino–ketone molecules [centroid–centroid distance = 3.724 (4) Å].
With the exception of the terminal benzene rings, the atoms in the title compound, C20H18ClN3O2, are approximately coplanar (r.m.s. deviation = 0.0495 Å). The benzene/chlorobenzene rings form dihedral angles of 3.02 (4) and 41.59 (5)°, respectively, with this plane. The hydroxy, amino and carbonyl groups all lie to the same side of the molecule, enabling the formation of intramolecular O—H⋯O and N—H⋯O hydrogen bonds that close S(6) rings. The configuration about the 2-butene bond is Z. Supramolecular chains mediated by C—H⋯Cl interactions and aligned along the c axis are found in the crystal packing. These assemble into layers that are connected by weak π–π interactions between centrosymmetrically related chlorobenzene rings [3.8156 (9) Å].
The molecule of the title compound, C20H19ClN4O4S, features a central pyrazole ring that possesses a benzene substituent, as well as a conjugated =C—C=C—Cmethyl substituent. The benzene ring is slightly twisted [dihedral angle = 7.7 (2)°] with respect to the five-membered ring; the mean plane of the zigzag =C—C=C—C fragment [torsion angle = 178.0 (4)°] is also slightly twisted [dihedral angle = 10.6 (4)°]. The amine and hydroxy groups form intramolecular hydrogen bonds. The amide group uses one of its H atoms to form a hydrogen bond to the sulfamyl O atom of an inversion-related molecule. Adjacent dimers are further linked by an N—Hamido⋯Npyrazole hydrogen bond to generate a linear chain. The crystal studied is a nonmerohedral twin with a minor twin component of 25.6 (2)%.
In the title compound, [PdBr(C27H23N3OPS)]·C3H6O, the coordination geometry about the PdII atom is distorted square-planar, arising from the attached Br, S, P and N atoms (N and Br are trans), the maximum deviation from the plane being 0.2053 (4) Å for the N atom. The three benzene rings attached to the P atom make dihedral angles of 69.78 (7), 87.05 (7) and 77.50 (7)° with each other. An intramolecular C—H⋯N hydrogen bond forms an S(6) ring motif. In the crystal, the complex molecules form infinite chains along the a-axis direction through C—H⋯Br interactions, and a C—H⋯O interaction links the main molecule with the acetone solvent molecule.
In the title compound, C25H22N4O2, the dihedral angles between the central pyrazole ring and the phenyl and benzene rings are 37.01 (3), 75.58 (7) and 49.67 (8)°. An intramolecular N—H⋯O hydrogen bond generates an S(6) motif. In the crystal, N—H⋯O hydrogen bonds link molecules into a zigzag chain extended along the b axis.
In the title compound, C25H14ClN3OS2, the central thiophene ring [maximum deviation = 0.011 (1) Å] makes dihedral angles of 55.72 (5), 13.36 (5) and 46.77 (4)° with the adjacent chloro-substituted benzene ring, the benzene ring and the 1,3-benzothiazole ring system [maximum deviation = 0.012 (1) Å], respectively. An intramolecular C—H⋯S(thienyl) hydrogen bond generates an S(6) ring motif in the molecule. In the crystal, molecules are linked by pairs of N—H⋯N hydrogen bonds into inversion dimers and the dimers are further connected by C—H⋯O hydrogen bonds into tapes running along . Aromatic π–π stacking interactions are also observed [centroid-to-centroid distances = 3.6116 (6) and 3.7081 (6) Å].
In the title compound, C24H24N2O3S, the phenyl rings form dihedral angles of 55.65 (11) and 79.60 (11)° with the plane of the thiophene ring. The molecular conformation is stabilized by an intramolecular N—H⋯O hydrogen bond, generating an S(6) ring motif. In the crystal, centrosymmetrically related molecules are linked into dimers by two pairs of C—H⋯O interactions.
In the title compound, C5H8N3
−·C7H5NO4, the non-H atoms of the 3,4-diaminopyridinium cation are coplanar, with a maximum deviation of 0.022 (1) Å. The carboxylate and nitro groups of the 4-nitrobenzoate anion are twisted out of the attached ring planes by dihedral angles of 15.89 (8) and 10.20 (8)°, respectively. In the 4-nitrobenzoic acid molecule, the carboxyl and nitro groups form dihedral angles of 18.25 (8) and 6.55 (8)°, respectively, with the benzene ring. In the crystal, the constituent units form two-dimensional networks parallel to (001) by O—H⋯O, N—-H⋯O and C—H⋯O hydrogen bonds. Weak π–π interactions involving inversion-related 4-nitrobenzoic acid molecules [centroid–centroid distance = 3.7325 (8) Å] and inversion-related 4-nitrobenzoate molecules [centroid–centroid distance = 3.7124 (8) Å] are also observed.
In the title compound, C14H13N3O2S, the dihedral angle between the thiophene and phenyl rings is 24.95 (8)°. The molecular structure is consolidated by intramolecular N—H⋯O and C—H⋯S interactions. The crystal structure features N—H⋯N and N—H⋯O hydrogen bonds forming centrosymmetric R
2(12) dimers, which are linked into a two-dimensional network parallel to (011) with an S(6)R
S(6) motif. In addition, π–π stacking interactions [centroid–centroid distance = 3.7013 (12) Å] occur between the thiophene and phenyl rings of adjacent molecules.
In the title compound, C19H19N4O2
+·Cl−·C2H3N, the dihedral angle between the two phenyl rings is 69.57 (8)° while the dihedral angles between the imidazole ring and the phenyl rings are 70.61 (7) and 82.11 (7)°. In the crystal, N—H⋯Cl, C—H⋯O, C—H⋯Cl and C—H⋯N hydrogen bonds link the imidazolium cations, chloride anions and acetonitrile solvent molecules into a two-dimensional hydrogen-bonded network parallel to (001); an intramolecular C—H⋯O hydrogen bond is also observed.
In the title compound, C13H15NO3, the dihydrofuranone ring is planar to within 0.012 (4) Å and it forms a dihedral angle of 42.8 (2)° with the benzene ring. The aminoethylidene group is coplanar with the dihydrofuranone ring. The methoxy group is slightly twisted away from the benzene ring. An intramolecular N—H⋯O hydrogen bond, generating an S(6) ring, is observed. In the crystal structure, the molecules exist as C—H⋯O hydrogen-bonded dimers.