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1.
Acta Crystallogr E Crystallogr Commun ; 78(Pt 1): 97, 2022 Jan 01.
Article in English | MEDLINE | ID: mdl-35081178

ABSTRACT

[This corrects the article DOI: 10.1107/S1600536804004799.].

2.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 12): 1852-1855, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-27980848

ABSTRACT

In the mol-ecular structure of the title compound, C23H14N4O7, the furan, di-nitro-phenyl and phenyl rings are almost in the same plane (r.m.s. deviation = 0.127 Å), with the benzoyl ring inclined by a dihedral angle of 56.4 (1)° to the three-ring system. A bifurcated intra-molecular N-H⋯(O,O) hydrogen bond is present. In the crystal, adjacent mol-ecules are linked by C-H⋯O hydrogen bonds into chains parallel to [001]. A π-π stacking inter-action between the benzoyl and di-nitro-phenyl moieties contributes to the crystal packing. Theoretical calculations using DFT(B3YLP) methods were used to confirm the mol-ecular structure.

3.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 8): 1187-9, 2016 Aug 01.
Article in English | MEDLINE | ID: mdl-27536410

ABSTRACT

The title compound, C11H6Cl2N2O2S, is a Schiff base that incorporates an N-bound 2,4-di-chloro-phenyl and a C-bound 5-nitro-thio-phene ring. The mol-ecule is approximately planar, the maximum deviation from the mean plane being 0.233 (4) Šfor the C=N N atom. The dihedral angle between the benzene and thio-phene rings is 9.7 (2)°. The C=N double bond has an E configuration. The crystal structure features C-H⋯O hydrogen bonds,forming sheets parallel to (10-1), and π-π stacking inter-actions between symmetry-related thio-phene and benzene rings, in which the distance between adjacent ring centroids is 3.707 (4) Å, forming a three-dimensional supramolecular structure. Geometric parameters from quantum-chemical calculations are in good agreement with experimental X-ray diffraction results.

4.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 7): o466-7, 2015 Jul 01.
Article in English | MEDLINE | ID: mdl-26279911

ABSTRACT

In the title compound, C15H11F3N2O4, the N=C bond of the central imine group adopts an E conformation. The dihedral angle between two benzene rings is 6.2 (2)°. There is an intra-molecular bifurcated O-H⋯(N,O) hydrogen bond with S(6) and S(9) ring motifs. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds into a helical chain along the 31 screw axis parallel to c. The -CF3 group shows rotational disorder over two sites, with occupancies of 0.39 (2) and 0.61 (2).

5.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): o883, 2013 Jun 01.
Article in English | MEDLINE | ID: mdl-23795059

ABSTRACT

The title Schiff base, C23H27ClN2O adopts the phenol-imine tautomeric form, with an intra-molecular O-H⋯N hydrogen bond, which generates an S(6) ring motif. Three C atoms of the heterocyclic moiety of the hexa-hydro-pyrido-quinoline unit, as well as the two methyl groups bonded to one of these C atoms, are disordered over two set of sites, with anoccupancy ratio of 0.740 (4):0.260 (4).

6.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): o889, 2013 Jun 01.
Article in English | MEDLINE | ID: mdl-23795065

ABSTRACT

In the title compound, C19H12Cl2N2O4, the imine bond length of 1.257 (6) Šis typical of a double bond. The dihedral angle between the para-nitro benzene ring and the central benzene ring is 12.06 (3)° and that between the central benzene and the para-chloro benzene ring is 73.81 (2)°. An intra-molecular O-H⋯N hydrogen bond generates an S(6) ring motif. In the crystal, mol-ecules are linked together by two pairs of C-H⋯O interactions (to the same O atom acceptor), forming inversion dimers. A short Cl⋯Cl contact [3.232 (4) Å] is observed.

7.
Article in English | MEDLINE | ID: mdl-23490260

ABSTRACT

4-(4-Methoxyphenethyl)-3,5-dimethyl-4H-1,2,4-triazole (3) was synthesized from the reaction of ethyl N'-acetylacetohydrazonate (1) with 2-(4-methoxyphenyl)ethanamine (2). The structure of the title compound 3 has been inferred through IR, (1)H/(13)C NMR, mass spectrometry, elemental analyses and combination of X-ray crystallography and theoretical methods. In addition to the molecular geometry from X-ray determination, the molecular geometry and vibrational frequencies of the title compound 3 in the ground state, were calculated using the density functional method (B3LYP) with the 6-31G(d) basis set. The calculated results show that the optimized geometry can well reproduce the crystal structure and the theoretical vibrational frequencies show good agreement with experimental values. The nonlinear optical properties are also addressed theoretically. The predicted nonlinear optical properties of 3 are greater than ones of urea. In addition, DFT calculations of molecular electrostatic potentials and frontier molecular orbitals of the title compound were carried out at the B3LYP/6-31G(d) level of theory.


Subject(s)
Models, Molecular , Quantum Theory , Triazoles/chemistry , Triazoles/chemical synthesis , Crystallography, X-Ray , Hydrogen Bonding , Magnetic Resonance Spectroscopy , Mass Spectrometry , Molecular Conformation , Nonlinear Dynamics , Spectroscopy, Fourier Transform Infrared , Static Electricity , Thermodynamics , Vibration
8.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): o2993-4, 2012 Oct 01.
Article in English | MEDLINE | ID: mdl-23125766

ABSTRACT

In the title compound, C(50)H(60)Cl(8)O(12), the mol-ecules are disordered about an inversion center located at the mid-point of the central C=C bond. These atoms show disorder and were modelled with two different orientations with site occupancies of 0.828 (3) and 0.172 (3). The dihedral angle between the two benzene rings in the asymmetric unit is 52.80 (6)°. Intramolecular C-H⋯O and C-H⋯Cl interactions occur and the crystal packing features inversion dimers linked by pairs of C-H⋯O bonds, generating R(2) (2)(10) loops.

9.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 9): o2633, 2012 Sep 01.
Article in English | MEDLINE | ID: mdl-22969533

ABSTRACT

The title mol-ecule, C(30)H(24)O(4), lies about an inversion center located at the mid-point of the central C=C bond. The diphenyl-methanone unit adopts an all-trans conformation. The dihedral angle between the adjacent rings is 53.57 (4)°.

10.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 9): o2801, 2012 Sep 01.
Article in English | MEDLINE | ID: mdl-22969674

ABSTRACT

The title Schiff base, C(13)H(13)NO(2)S, adopts the phenol-imine tautomeric form and reveals an intra-molecular O-H⋯N hydrogen bond involving the hy-droxy group and the imino N atom, forming an S(6) ring. The mol-ecule is highly twisted with respect to the central imine group, which is reflected in the dihedral angle of 67.83 (10)° formed by the thienyl and phenol rings. The crystal packing is characterized by weak C-H⋯O and C-H⋯π inter-actions.

11.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): o1587, 2012 Jun 01.
Article in English | MEDLINE | ID: mdl-22719398

ABSTRACT

The title Schiff base, C(19)H(24)N(2)O(3), exists in the crystal structure in the phenol-imine tautomeric form with an intra-molecular O-H⋯N hydrogen bond. The planes of the aromatic rings form a dihedral angle of 36.8 (8)°. The crystal packing is characterized by C-H⋯O hydrogen bonds and π-π stacking inter-actions [centroid-centroid distance = 3.478 (4)Å].

12.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): o1651-2, 2012 Jun 01.
Article in English | MEDLINE | ID: mdl-22719449

ABSTRACT

The asymmetric unit of the title compound, C(13)H(17)N(3)O(2), contains eight crystallographically independent mol-ecules. The planes of the benzene and triazole rings in the eight mol-ecules make dihedral angles of 5.53 (13), 9.33 (13), 19.28 (11), 17.36 (8), 12.84 (12), 8.03 (8), 19.97 (11), and 7.98 (8)°. The eight mol-ecules in the asymmetric unit are linked by inter-molecular O-H⋯O and N-H⋯O hydrogen bonds, forming a three-dimensional network.

13.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 5): o1279, 2012 May 01.
Article in English | MEDLINE | ID: mdl-22590194

ABSTRACT

In the title mol-ecule, C(7)H(7)N(3)S(2), the dihedral angle between the thio-phene and thia-diazole rings is 72.99 (5)°; the two rings are oriented so that the S atoms in each ring are on the same side. In the crystal, the three-dimensional network involves strong N-H⋯O hydrogen bonds, as well as C-H⋯π and π-π stacking inter-actions [centroid-centroid distances = 3.654 (1) and 3.495 (1) Å].

14.
Article in English | MEDLINE | ID: mdl-22465776

ABSTRACT

The triazol compound 4-(4-methoxyphenethyl)-5-benzyl-2H-1,2,4-triazol-3(4H)-one monohydrate (I) has been synthesized and characterized by (1)H NMR, (13)C NMR, IR, and X-ray single-crystal determination. The molecular geometry, vibrational frequencies and gauge including atomic orbital (GIAO) (1)H and (13)C NMR chemical shift values of (I) in the ground state have been calculated using the density functional method (B3LYP) with the 6-31G(d) basis set. The calculated results show that the optimized geometry can well reproduce the crystal structure, and the theoretical vibrational frequencies and chemical shift values show good agreement with experimental values. The energetic behavior of (I) in solvent media was examined using the B3LYP method with the 6-31G(d) basis set by applying the Onsager and the polarizable continuum model (PCM). The predicted non-linear optical properties of (I) are greater than ones of urea. In addition, DFT calculations of molecular electrostatic potentials, frontier molecular orbitals and thermodynamic properties of (I) were carried out at the B3LYP/6-31G(d) level of theory.


Subject(s)
Triazoles/chemistry , Crystallography, X-Ray , Magnetic Resonance Spectroscopy , Models, Molecular , Quantum Theory , Spectroscopy, Fourier Transform Infrared , Static Electricity
15.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 11): o3213-4, 2012 Nov 01.
Article in English | MEDLINE | ID: mdl-23284520

ABSTRACT

The title compound, C(16)H(19)N(3)O(4)S, is almost planar, with a dihedral angle of 2.88 (9)° between the mean planes of the benzene and thia-zole rings. The mol-ecule adopts an E conformation about the two C=N bonds, with a C-N-N-C torsion angle of -177.01 (11)°. An intra-molecular C-H⋯O hydrogen bond exists between a thia-zole methyl group and the formic acid ethyl ester carbonyl O atom. In the crystal, mol-ecules are linked by O--H⋯O hydrogen bonds, forming chains propagating along [2-10]. The chains are linked via C-H⋯O hydrogen bonds with R(2) (2)(12) ring motifs, forming sheets lying parallel to (12-2). The sheets are further linked through out-of-plane C-H⋯N hydrogen bonds with R(2) (2)(12) ring motifs and C-H⋯π inter-actions, forming an inter-esting three-dimensional supra-molecular architecture.

16.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 6): o1294, 2010 May 08.
Article in English | MEDLINE | ID: mdl-21579391

ABSTRACT

In the title compound, C(13)H(15)N(3)O(3), the dihedral angle between the two aromatic ring is 51.06 (1)°. In the crystal, mol-ecules are connected by pairs of N-H⋯O hydrogen bonds into centrosymmetric dimers.

17.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 8): o2158, 2010 Jul 31.
Article in English | MEDLINE | ID: mdl-21588442

ABSTRACT

The dihedral angle between the two rings in the title compound, C(12)H(15)N(3)O(2), is 49.03 (1)°. The crystal structure is stabilized by inter-molecular N-H⋯O and C-H⋯O hydrogen bonds and π-π stacking inter-actions between the triazole rings with a centroid-centroid distance of 3.394 Å.

18.
J Mol Model ; 16(3): 447-57, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19629547

ABSTRACT

The triazole compound, 5-benzyl-4-(3,4-dimethoxyphenethyl)-2H-1,2,4-triazol-3(4H)-one, has been synthesized and characterized by (1)H-NMR, (13)C-NMR, IR, and X-ray single-crystal determination. The compound crystallizes in the monoclinic space group P2(1) with a = 11.8844(3) A, b = 17.5087(4) A, c = 17.3648(6) A, beta = 99.990(2) and Z = 8. In addition to the molecular geometry from X-ray experiment, the molecular geometry, vibrational frequencies and gauge including atomic orbital (GIAO) (1)H- and (13)C-NMR chemical shift values of the title compound in the ground state have been calculated using the density functional method (B3LYP) with 6-31G(d,p) basis set. The calculated results show that the optimized geometries can well reproduce the crystal structure and the theoretical vibrational frequencies and chemical shift values show good agreement with experimental ones. Besides, molecular electrostatic potential (MEP), natural bond orbital (NBO), and frontier molecular orbitals (FMO) analysis of the title compound were performed by the B3LYP/6-31G(d,p) method.


Subject(s)
Computer Simulation , Models, Chemical , Triazoles/chemistry , Crystallography, X-Ray , Hydrogen Bonding , Magnetic Resonance Spectroscopy , Models, Molecular , Spectrophotometry, Infrared , Static Electricity , Thermodynamics , Triazoles/chemical synthesis , Vibration
19.
J Mol Model ; 15(10): 1281-90, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19333628

ABSTRACT

The Schiff base compound, N-n-Decyl-2-oxo-5-nitro-1-benzylidene-methylamine, has been -synthesized and characterized by IR, electronic spectroscopy, and X-ray single-crystal determination. Molecular geometry from X-ray experiment of the title compound in the ground state have been compared using the Hartree-Fock (HF) and density functional method (B3LYP) with 6-31G(d) basis set. Calculated results show that density functional theory (DFT) at B3LYP/6-31G(d) level can well reproduce the structure of the title compound. To investigate the solvent effect for the atomic charge distributions of the title compound, self-consistent reaction field theory with Onsager reaction field model was used. In addition, DFT calculations of the title compound, molecular electrostatic potential and thermodynamic properties were performed at B3LYP/6-31G(d) level of theory.


Subject(s)
Benzylidene Compounds/chemistry , Cyclohexanones/chemistry , Models, Molecular , Schiff Bases/chemistry , Models, Theoretical , Thermodynamics
20.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 12): o3039, 2009 Nov 07.
Article in English | MEDLINE | ID: mdl-21578774

ABSTRACT

All the non-H atoms of the title compound, C(10)H(10)N(4)O(3), are almost coplanar, the maximum deviation from planarity being 0.065 (3) Å. The dihedral angle between the aromatic rings is 1.66 (6)°. The mol-ecule adopts the enol-imine tautomeric form with an intra-molecular hydrogen-bonding inter-action between the Schiff base N atom and the hydr-oxy group. In the crystal, inter-molecular N-H⋯O and O-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional network.

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