In the title compound, C22H16F3N, the C=N bond of the central imine group adopts an E conformation. The dihedral angles between the 2-(trifluoromethyl)phenyl ring and the benzene rings are 9.34 (1) and 68.8 (1)°. The imine group displays a C—C—N=C torsion angle of 41.6 (3)°. In the crystal, weak C—H⋯F hydrogen bonds link the molecules into chains parallel to the b-axis direction.
In the title compound, C21H16N2O2, the 3-nitrophenyl and two phenyl rings are twisted from the mean plane of the enimino fragment by 44.4 (1), 37.2 (1) and 74.1 (1)°, respectively. The crystal packing exhibits no classical intermolecular contacts.
The title compound, C25H19N, adopts an E conformation about the C=N bond. The naphthalene ring system and the phenyl rings form dihedral angles 38.1 (1), 46.9 (8) and 48.5 (1)°, respectively, with the mean plane of the central enimino fragment. The crystal packing exhibits no directional close contacts.
The title compound, C18H12N2, adopts an E conformation with the benzylidenemalononitrile and phenyl groups located on opposite sides of the C=C bond. The two phenyl rings are oriented at a dihedral angle of 62.49 (7)°.
In the title compound, C22H20N2O2S, the molecule adopts a twisted E configuration around the C=N bond. The two phenyl rings are twisted from each other, making a dihedral angle of 78.00 (12)°. The methyl-substituted benzene ring makes dihedral angles of 32.37 (14) and 69.70 (12)° with the two phenyl rings. In the crystal structure, molecules are linked into extended chains along the b axis through intermolecular N—H⋯O hydrogen bonds.
In the title compound, C19H14N2O2, the dihedral angle between the mean planes of the 4-nitrophenyl ring and the naphthalene ring system is 12.79 (2)°. The imine group displays a C—C—N=C torsion angle of 41.0 (2)° and the C=N group has an E conformation. In the crystal, weak C—H⋯O hydrogen bonds link molecules into layers parallel to the b axis.
In the title compound, C20H17NO, the dihedral angle between the mean planes of the 4-methoxyphenyl ring and the naphthalene ring is 69.50 (7)°. The methoxy group is almost coplanar with the benzene ring to which it is connected [Cb—Cb—Om—Cm torsion angle of −7.9 (2)°; b = benzene and m = methoxy] and the imine group displays a C—C—N=C torsion angle is −57.2 (2)°. The imine (C=N) group has an E conformation. In the crystal, weak π–π interactions between the benzene rings [centroid–centroid distance = 3.7781 (10) Å] are observed.
crystal structure; naphthalene derivative; π–π interactions
The title compound, C19H15N3O2, shows an E conformation of the imine bond. The dihedral angle between the planes of the phenyl rings in the diphenylhydrazine groups is 88.52 (4)°. The 2-nitrobenzene ring shows a torsion angle of 10.17 (8)° with the C=N—N plane. A short intramolecular C—H⋯O contact occurs. In the crystal, only van der Waals contacts occur between the molecules.
crystal structure; hydrazine; hydrogen bonding
In the title compound, C13H10N2O2, a Schiff base derivative, the dihedral angle between the two aromatic rings is 31.58 (3)°. The C=N double bond is essentially coplanar with the nitrophenyl ring. The torsion angle of the imine double bond is 175.97 (13)°, indicating that the C=N double bond is in a trans configuration. The crystal structure is stabilized by C—H⋯O contacts and π–π interactions (centroid–centroid distances of 3.807 and 3.808Å).
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
The molecular structure of the title compound, C26H18N4O6S·C2H6OS, shows an E conformation of the hydrazone double bond. The presence of a methylene group between the benzo[de]isoquinoline and benzenesulfonyl moieties allows the 4-nitrophenyl ring and the benzo[de]isoquinoline system to be parallel with respect to each other, so that the molecule adopts a U-shaped spatial conformation. The dihedral angle between mean planes of these aromatic groups is 4.4 (1)°. This special arrangement enables neighboring molecules to be intercalated, forming slipped π–π interactions [centroid–centroid distance = 3.535 (2) Å] between the 4-nitrophenyl and benzo[de]isoquinoline groups and point-to-face C—H⋯π interactions between the benzo[de]isoquinoline and benzenesulfonyl aromatic systems. In addition, the crystal packing also features an intermolecular N—H⋯O interaction involving the amine group and the dimethyl sulfoxide solvent molecule.
In the title compound, C22H18N2O3S, disorder is found in the benzoyl group (A and B), as well as for four C atoms of the cyclohexene ring. Two orientations were modeled in a 0.583 (5):0.417 (5) ratio. The cyclohexene ring is in a distorted chair conformation. The dihedral angles between the mean plane of the thiophene ring and the 4-nitrobenzene and phenyl rings are 30.9 (8) and 64.8 (3) (A) and 62.4 (7)° (B). The mean planes of the 4-nitrobenzene and the phenyl rings are almost perpendicular to each other, with dihedral angles of 85.4 (1) (A) and 83.9 (8)° (B). An extensive array of weak C—H⋯O interactions consolidate molecules into a three-dimensional architecture, forming chains along  and  and layers parallel to (011).
The title compound crystallized with two independent molecules in the asymmetric unit. In the crystal, they are linked to one another, forming chains enclosing (10) and (12) ring motifs.
The title compound, C22H17NO4, crystallizes with two independent molecules (A and B) in the asymmetric unit. Each molecule exists as an E isomer with C—C=C—C torsion angles of −175.69 (17) and −178.41 (17)° in A and B, respectively. In molecule A, the planes of the terminal benzene rings are twisted by an angle of 26.67 (10)°, while the biphenyl unit is non-planar, the dihedral angle between the rings being 30.81 (10)°. The dihedral angle between the nitrophenyl ring and the inner phenyl ring is 6.50 (9)°. The corresponding values in molecule B are 60.61 (9), 31.07 (8) and 31.05 (9)°. In the crystal, molecules are arranged in a head-to-head manner, with the 3-nitrophenyl groups nearly parallel to one another. The A and B molecules are linked to one another via C—H⋯O hydrogen bonds, forming chains lying parallel to (-320) and enclosing R
2(10) and R
2(12) ring motifs. The methoxy group in both molecules is positionally disordered with a refined occupancy ratio of 0.979 (4):0.021 (4) for molecule A and 0.55 (4):0.45 (4) for molecule B.
crystal structure; chalcones; C—H⋯O hydrogen bonding; main-residue disorder
In the title compound, C19H18N4O4, the nitrophenyl and phenyl rings are twisted by 67.0 (6) and 37.4 (4)°, respectively, with respect to the pyrazole ring plane [maximum deviation = 0.0042 (16) Å]. The dihedral angle between the mean planes of the phenyl rings is 59.3 (3)°. The amide group, with a C—N—C—C torsion angle of 177.54 (13)°, is twisted away from the plane of the pyrazole ring in an antiperiplanar conformation. In the crystal, N—H⋯O hydrogen bonds involving the carbonyl group on the pyrazole ring and the amide group, together with weak C—H⋯O interactions forming R
2(10) graph-set motifs, link the molecules into chains along . Additional weak C—H⋯O interactions involving the nitrophenyl rings further link the molecules along , also forming R
2(10) graph-set motifs, thereby generating (010) layers.
In the title compound, C15H15N5O2S2, the phenyl rings make dihedral angles of 4.03 (4) and 9.77 (5)° with the plane defined by the central N—N—C—N—N atoms (r.m.s. deviation = 0.010 Å). The C—S—C—C torsion angles of the methylsulfanyl groups with their respective phenyl rings are −7.47 (13) and −72.07 (13)°. The shortest centroid–centroid distance of 3.707 Å occurs between the two π-systems N—N—C—N—N and the benzene ring in the diazene 1-position. The H atom bound to the N atom is involved in intramolecular N—H⋯N and N—H⋯S contacts, while the nitro O atoms are involved in intermolecular C—H⋯O contacts.
In the title compound, C29H25N3O3, the imine double bond has an E configuration. The dihedral angle between the hydroxyphenyl and benzene rings in the imine moiety is 26.95 (9)°, and the dihedral angle between the hydroxyphenyl and benzimidazole rings in the other moiety is 14.83 (9)°. These angles are probably limited to small values as a consequence of two strong intramolecular O—H⋯N hydrogen bonds formed between the hydroxy groups and the imine and imidazole N atoms. The aliphatic chain linking the two ring systems has a gauche conformation, as reflected in C—C—C—O torsion angle of 70.9 (2)°.
The title compound, C16H13NO3, crystallizes with two independent molecules (A and B) in the asymmetric unit. The dihedral angle between the mean planes of the 4-methylphenyl and 3-nitrophenyl groups is 4.0 (3)° in molecule A and 16.2 (7)° in molecule B. Intermolecular C—H⋯O hydrogen bonding involving the O atoms of the 3-nitrophenyl group of both independent molecules link the molecules into layers approximately parallel to the (110) plane. The layers are held together by π–π stacking interactions between the 4-methylphenyl ring of molecule A and the 3-nitrophenyl ring of molecule B of the adjacent layer, with the distance between the centroids of interacting rings being 3.6987 (7) Å.
The asymmetric unit of the title compound, C19H15N3O2, contains two molecules, both of which show an E conformation of the imine bond. The dihedral angles between the phenyl rings in the phenylhydrazine groups are 86.09 (6) and 83.41 (5)° in the two molecules. The 4-nitrobenzene rings show torsion angles of 4.4 (2) and 10.9 (2)° from the two C=N—N planes. In the crystal, C—H⋯π interactions and C—H⋯O hydrogen bonds are observed growing along the a, b and c axes, resulting in a complex supramolecular array.
In the title compound, C16H13BrN4O4S, the dihedral angle between the aromatic rings is 4.1 (2)° and the C=N—N=C torsion angle is 175.5 (3)°. The nitro group is almost coplanar with the benzene ring to which it is attached [dihedral angle = 2.9 (7)°]. The thiazine ring has an S-envelope conformation with the S atom displaced by 0.819 (3) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.017 Å). In the crystal, C—H⋯O interactions link the molecules and weak aromatic π–π stacking [centroid–centroid separation = 3.874 (2) Å] is also observed.
The title compound, C14H13N3O4, is close to planar, the dihedral angle between the terminal benzene rings being 5.80 (16)°; the nitro group is coplanar with the benzene ring to which it is bonded [O—N—C—C torsion angle = −177.3 (3)°]. The hydroxy group forms an intramolecular hydrogen bond with the imine N atom, and the conformation about the imine bond is E. In the crystal, layers in the (101) plane with an undulating topology are formed by O—H⋯O and N—H⋯O hydrogen bonds along with C—H⋯O interactions. Centrosymmetrically related layers are connected via π–π interactions [ring centroid–centroid distance = 3.5739 (19) Å] into double layers.
The title compounds are the 3-ethyl, (I), and 3-isopropyl, (II), derivatives of (1-methyl-2,6-diphenylpiperidin-4-ylidene)amino phenyl carbonate. The main difference in the conformation of the two compounds is the angle of inclination of the phenoxycarbonyl ring with respect to the piperidine ring mean plane, with a dihedral angle of 2.05 (8)° in (I) and 45.24 (13)° in (II).
In the title compounds, C27H28N2O3, (I), and C28H30N2O3, (II), the conformation about the C=N bond is E. The piperidine rings adopt chair conformations with the attached phenyl rings almost normal to their mean planes, the dihedral angles being 85.82 (8) and 85.84 (7)° in (I), and 87.98 (12) and 86.42 (13)° in (II). The phenyl rings are inclined to one another by 52.87 (8)° in (I) and by 60.51 (14)° in (II). The main difference in the conformation of the two compounds is the angle of inclination of the phenoxycarbonyl ring to the piperidine ring mean plane. In (I), these two planes are almost coplanar, with a dihedral angle of 2.05 (8)°, while in (II), this angle is 45.24 (13)°. In the crystal of (I), molecules are linked by C—H⋯O hydrogen bonds, forming inversion dimers with R
2(14) loops. The dimers are linked via C—H⋯π interactions forming a three-dimensional network. In the crystal of (II), there are no significant intermolecular interactions present.
crystal structure; piperidine; oxime; 2,6-diphenylpiperidine
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.
The reaction of [CoIII(TPP)Cl] (TPP is the dianion of 5,10,15,20-tetraphenylporphyrin) with an excess of 4-nitroaniline in dichloromethane leads to the title compound, [CoIII(C44H28N4)(C6H6N2O2)2]Cl·CH2Cl2. The CoIII ion lies on an inversion centre and is octahedrally coordinated by two N atoms of the NH2 groups of the two 4-nitroaniline trans-axial ligands and four pyrrole N atoms of the porphyrin. The asymmetric unit contains one half of the [CoIII(TPP)(4-nitroaniline)2]+ ion complex, one chloride counter-ion (lying on a twofold rotation axis) and one half dichloromethane solvent molecule, where the C atom lies on a twofold rotation axis. The average equatorial Co—N(pyrrole) distance (Co—Np) is 1.982 (2) Å and the axial Co—N(4-nitroaniline) bond length is 2.006 (2) Å. The crystal packing is stabilized by an N—H⋯Cl hydrogen bond between the N atom of the amino group of the 4-nitroaniline axial ligand and the chloride counter-ion. The supramolecular architecture is further stabilized by weak C—H⋯π interactions.
crystal structure; cobalt(III) complex; 5,10,15,20-tetraphenylporphyrin ligand
Molecules of the title compound, C16H16N4O7, are not planar with a dihedral angle of 5.50 (11)° between the substituted benzene rings. The two meta-methoxy groups of the 3,4,5-trimethoxybenzene moiety lie in the plane of the attached ring [Cmethyl–O–C–C torsion angles −0.1 (4)° and −3.7 (3)°] while the para-methoxy substituent lies out of the plane [Cmethyl—O—C—C, −86.0 (3)°]. An intramolecular N—H⋯O hydrogen bond involving the 2-nitro substituent generates an S(6) ring motif. In the crystal structure, molecules are linked by weak C—H⋯O interactions into screw chains, that are arranged into a sheet parallel to the bc plane. These sheets are connected by π–π stacking interactions between the nitro and methoxy substituted aromatic rings with a centroid–centroid separation of 3.9420 (13) Å. C—H⋯π contacts further stabilize the two-dimensional network.
The title compound crystallizes as a hemihydrate, C18H20N2O5·0.5H2O. The molecule exists in an E conformation with respect to the C=N imine bond. The 4-methoxyphenyl unit is disordered over two sets of sites with a refined occupancy ratio of 0.54 (2):0.46 (2). The dihedral angles between the benzene rings are 29.20 (9) and 26.59 (9)°, respectively, for the major and minor components of the 4-methoxy-substituted ring. All methoxy substituents lie close to the plane of the attached benzene rings [the Cmethyl—O—C—C torsion angles range from −4.0 (12) to 3.9 (2)°]. In the crystal, the components are linked into chains propagating along  via N—H⋯O and O—H⋯O hydrogen bonds and weak C—H⋯O interactions.