214 research outputs found
4-(1,2,4-Triazol-1-yl)aniline
In the title compound, C8H8N4, the dihedral angle between the triazole ring [maximum deviation = 0.003 (1) Å] and the benzene ring is 34.57 (7)°. In the crystal, molecules are linked into sheets lying parallel to the ac plane via intermolecular N—H⋯N and C—H⋯N hydrogen bonds. Aromatic π–π [centroid–centroid distance = 3.6750 (8) Å] stacking and N—H⋯π interactions are also observed
4-{[(E)-(3-Phenyl-1H-pyrazol-4-yl)methylidene]amino}-1H-1,2,4-triazole-5(4H)-thione
In the title compound, C12H10N6S, a weak intramolecular C—H⋯S hydrogen bond stabilizes the molecular conformation. The pyrazole and triazole rings form a dihedral angle of 17.82 (8)°. The molecule adopts an E configuration with respect to the central C=N double bond. In the crystal, intermolecular N—H⋯N and N—H⋯S hydrogen bonds link molecules into chains propagating in [20]
Synthesis and characterization of Schiff base metal complexes and reactivity studies with maleimide epoxy resin
A novel maleimide epoxy contg. Co(II), Ni(II), and Cu(II) ions have been synthesized by curing a maleimide epoxy resin (MIEB-13) with Co(II), Ni(II), and Cu(II) complexes of a macrocyclic bis-hydrazone Schiff base. The Schiff base was synthesized by reacting terephthaloyl dihydrazide with 2,6-diformyl-4-methylphenol. The Schiff base and its Co(II), Ni(II), and Cu(II) complexes have been characterized by elemental analyses, spectral (IR, 1H NMR, UV-vis., FAB mass, ESR), thermal, and magnetic data. The curing reaction of the epoxy resin was carried out with the metal complex crosslinking agents. The stability of the cured samples was studied by thermogravimetric analyses; the products have excellent chem. (acid/alkali/solvent) and water absorption resistance. Further, SEM and DSC techniques confirmed the phase homogeneity of the cured systems
N-(5-Bromopyridin-2-yl)acetamide
The asymmetric unit of the title compound, C7H7BrN2O, contains two molecules, in one of which the methyl H atoms are disorderd over two orientations in a 0.57 (3):0.43 (3) ratio. The dihedral angles between the pyridine rings and the acetamide groups are 7.27 (11) and 8.46 (11)°. In the crystal, molecules are linked by N—H⋯O and C—H⋯O hydrogen bonds generating bifurcated R
2
1(5) ring motifs, which in turn lead to [110] chains
(2E)-1-(2,4-Dichlorophenyl)-3-[3-(4-nitrophenyl)-1-phenyl-1H-pyrazol-4-yl]prop-2-en-1-one
In the title compound, C24H15Cl2N3O3, the C=C double bond is E configured. The 1-phenyl-1H-pyrazole moiety is roughly planar (r.m.s. deviation of all fitted non-H atoms = 0.0780 Å), but the mean planes of the two components are inclined at an angle of 9.95 (7)°. The mean plane defined by the non-H atoms of the 1H-pyrazole ring encloses angles of 9.95 (7), 24.54 (6) and 43.02 (6)° with the mean planes of the different benzene rings. In the crystal, C—H⋯O contacts are present and result in the formation of a double-layer two-dimensional network lying parallel to (110). The shortest intercentroid distance between two aromatic systems is 3.5455 (7) Å and is apparent between two pyrazole systems. Further π–π interactions are manifest between a pair of 4-nitrophenyl rings [centroid-to-centroid distance = 3.6443 (7) Å] and a pair of 2,4-dichlorophenyl rings [centroid-to-centroid distance = 3.7797 (7) Å]
(2E)-3-(1,3-Diphenyl-1H-pyrazol-4-yl)-1-phenylprop-2-en-1-one
In the title compound, C24H18N2O, the pyrazole ring is essentially planar [maximum deviation = 0.004 (1) Å] and makes dihedral angles of 18.07 (4), 48.60 (4) and 9.13 (5)° with the phenyl rings. In the crystal, adjacent molecules are connected via intermolecular C—H⋯O hydrogen bonds, forming dimers. Furthermore, the crystal structure is stabilized by weak C—H⋯π and π–π interactions, with centroid–centroid distances of 3.6808 (5) Å
(4-Chloro-2-fluorophenyl)[1-(2,6-difluorophenyl)but-3-enyl]amine
In the molecule of the title homoallylic amine, C16H13ClF3N, the dihedral angle between the two benzene rings is 84.63 (4)°. Weak intramolecular N—H⋯F hydrogen bonds generate S(6) and S(5) ring motifs. In the crystal structure, weak intermolecuar N—H⋯F hydrogen bonds link molecules into centrosymmetric dimers which are arranged in molecular sheets parallel to the ac plane
(E)-1-(2,4-Dichlorophenyl)-3-[3-(4-methoxyphenyl)-1-phenyl-1H-pyrazol-4-yl]prop-2-en-1-one
In the title molecule, C25H18Cl2N2O2, the dihedral angles between the pyrazole ring and its N- and C-bonded benzene rings are 8.28 (11) and 40.89 (10)°, respectively. The dihedral angle between the benzene rings is 39.03 (11)°. The title molecule exists in a trans conformation with respect to the acyclic C=C bond. In the crystal, molecules are linked into inversion dimers by pairs of intermolecular C—H⋯O hydrogen bonds, generating R
2
2(14) loops
(1Z)-1-(2,4-Dichlorophenyl)ethan-1-one semicarbazone
In the title compound, C9H9Cl2N3O, the semicarbazone group is approximately planar, with an r.m.s deviation from the mean plane of 0.011 (2) Å. The dihedral angle between the least-squares planes through the semicarbazone group and the benzene ring is 38.76 (9)°. The crystal structure is further stabilized by N—H⋯O and C—H⋯O hydrogen bonding
1-Dibromomethyl-4-methoxy-2-nitrobenzene
The asymmetric unit of the title compound, C8H7Br2NO3, comprises two crystallographically independent molecules (A and B). The nitro groups are twisted from the attached benzene rings, making dihedral angles of 39.26 (9) and 35.90 (9)° in molecules A and B, respectively. In each molecule, the dibromomethyl group is orientated in such a way that the two Br atoms are tilted away from the benzene ring. An interesting features of the crystal structure is the two short Br⋯Br interactions which, together with intermolecular C—H⋯O hydrogen bonds, link the molecules into an extended three-dimensional network. The crystal structure is further stabilized by weak C—H⋯π interactions
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