Sümeyye Gümüş

Crystal structure, spectroscopic studies and quantum mechanical calculations of 2-[((3-iodo-4-methyl)phenylimino)methyl]-5-nitrothiophene

The title compound, 2-[((3-iodo-4-methyl)phenylimino)methyl]-5-nitrothiophene, C12H9O2N2I1S1, was synthesized and characterized by IR, UV-Vis and single-crystal X-ray diffraction technique. The molecular structure was optimized at the B3LYP, B3PW91 and PBEPBE levels of the density functional method (DFT) with the 6-311G+(d,p) basis set. Using the TD-DFT method, the electronic absorption spectra of the title compound was computed in both the gas phase and ethanol solvent. The harmonic vibrational frequencies of the title compound were calculated using the same methods with the 6-311G+(d,p) basis set. The calculated results were compared with the experimental determination results of the compound. The energetic behavior such as the total energy, atomic charges, dipole moment of the title compound in solvent media were examined using the B3LYP, B3PW91 and PBEPBE methods with the 6-311G+(d,p) basis set by applying the Onsager and the polarizable continuum model (PCM). The molecular orbitals (FMOs) analysis, the molecular electrostatic potential map (MEP) and the nonlinear optical properties (NLO) for the title compound were obtained with the same levels of theory. And then thermodynamic properties for the title compound were obtained using the same methods with the 6-311G(d,p) basis set.

2-Ethyl-N-[(5-nitro­thio­phen-2-yl)methyl­idene]aniline

In the title compound, C13H12N2O2S, the dihedral angle between the benzene and thiophene rings is 36.72 (8)°. An intermolecular C—H⋯π interaction contributes to the stability of the crystal structure.

(E)-3-chloro-N-((5-nitrothiophen-2-yl)methylene)aniline: a combined crystallographic, theoretical and antimicrobial activity investigation.

The title molecule, (E)-3-chloro-N-((5-nitrothiophen-2-yl)methylene)aniline, (C(11)H(7)ClN(2)O(2)S), was synthesized and characterized by IR and single-crystal X-ray structure determination. The compound crystallizes in the monoclinic space group P2(1)/c. In addition, the molecular geometry, vibrational frequencies and frontier molecular orbitals analysis of the title compound in the ground state have been calculated by using the PM3 semi-empirical, HF/6-31G(d) and B3LYP/6-31G(d) ab initio methods. The results of the optimized molecular structure are exhibited and compared with the experimental X-ray diffraction and the calculated results are show that the optimized geometry can well reproduce the crystal structure. The Schiff base compounds are very important in medicinal and pharmaceutical fields because of their wide spectrum of biological activities. Most of them show biological activities such as antimicrobial, antifungal as well as antitumor activity. Therefore, (C(11)H(7)ClN(2)O(2)S) was investigated for their antimicrobial activities, Gram-positive and Gram-negative bacteria.

5-Diethyl-amino-2-[(E)-(2,4-dimeth-oxy-phen-yl)imino-meth-yl]phenol.

The title Schiff base, C19H24N2O3, exists in the crystal structure in the phenol–imine tautomeric form with an intramolecular 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 interactions [centroid–centroid distance = 3.478 (4)Å].

(E)-3-[(2-Methyl-4-nitro-phen-yl)imino-meth-yl]-1-benzothio-phene.

In the title conpound, C16H12N2O2S, the 1-benzothiophene residue and the substituted benzene ring are oriented at a dihedral angle of 53.36 (6)°. The molecular conformation features a short C—H⋯N contact. There are no significant intermolecular contacts.

(E)-2-[3-(Trifluoro­meth­yl)phenyl­imino­meth­yl]benzene-1,4-diol

In the title compound, C14H10F3NO2, the two benzene rings are oriented at a dihedral angle of 31.94 (14)°. An intramolecular O—H⋯N hydrogen bond helps to stabilize the molecular structure. In the crystal, intermolecular O—H⋯O hydrogen bonding links the molecules, forming chains running along the crystallographic a axis. The F atoms of the trifluoromethyl group are disordered over two positions with refined site occupancies of 0.488 (5) and 0.512 (5).

Crystal structure and computational study of 2,4-di-chloro-N-[(E)-(5-nitro-thio-phen-2-yl)methyl-idene]aniline.

The title compound, C11H6Cl2N2O2S, is a Schiff base that incorporates an N-bound 2,4-dichlorophenyl and a C-bound 5-nitrothiophene ring. The crystal structure features C—H⋯O hydrogen bonds and π–π stacking interactions. Geometric parameters from quantum-chemical calculations are in good agreement with experimental X-ray diffraction results.

Crystal Structure, Spectroscopy, SEM Analysis, and Computational Studies of N-(1,3-Dioxoisoindolin-2yl)benzamide

The compound N-(1,3-dioxoisoindolin-2yl)benzamide, C15H10N2O3, was prepared by the heating of an ethanolic solution of 2-hydroxy-1H-isoindole-1,3(2H)-dione and 4-chloroaniline. The product was characterised using a combination of IR spectroscopy, SEM, and single crystal X-ray diffraction techniques. In addition to the experimental analysis, theoretical calculations were used to investigate the crystal structure in order to compare experimental and theoretical values. The X-ray diffraction analysis shows that the compound crystallises in the monoclinic space group with the geometric parameters of , , , and °. The crystal structure is held together by a network of N-H⋯O hydrogen bonds involving the carboxamide group.

Structure of (E)-N-((5-Nitrothiophen-2-YL)Methylene)-3-(Trifluoromethyl)Aniline

The Schiff base compound, C12H7N2O2F3S, has been synthesized and characterized by IR, UV-Vis, 1H-NMR, 13C-NMR and singlecrystal X-ray diffraction (XRD) and elemental analysis. The compound, an Ortep-3 [1] view of which is shown in Fig. 1, crystallizes in the monoclinic space group P-1 with a= 7.5700(11) Å, b= 12.8280(16) Å, c= 13.0170(16) Å, α= 89.295(10)o, β= 88.691(11)o, γ= 82.246(11)o and Z=4 in the unit cell. The molecular structure is stabilized by C-H...O and C-H...F intramolecular hydrogen bonds and molecules are linked through intermolecular C-H...O and C-H...F type hydrogen bonds and C-H...Cg (π-ring) interaction. The molecular geometry from X-ray determination of the title compound in the ground state has been compared using the Hartre-Fock (HF) and density functional theory (DFT/B3LYP) [2] with 6-31G(d) [3] basis set. The results of the optimized molecular structure are exhibited and compared with the experimental X-ray diffraction. To determine conformational flexibility, molecular energy profile of the title compound was obtained by B3LYP with the 6-31G(d) basis set calculations with respect to selected degree of torsional freedom, which was varied from −180° to +180° in steps of 10°. In addition, molecular electrostatic potential (MEP) distribution and frontier molecular orbitals (FMOs) properties of the title molecule were investigated by theoretical calculations at the B3LYP/6-31G (d) level. Figure 1. Ortep 3 diagram of the title compound. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.

Experimental and DFT studies of 4-methoxy-N-[(E)-(5-nitrothiophen-2-yl)methylidene]aniline

The title molecule, C12H10N2O3S, is nonplanar with an interplanar angle of 33.44(7) 0 between the benzene and thiophene rings. In the crystal there exist only weak intermolecular C—H...O interactions, π interactions π...between the benzene rings [centroid–centroid distance = 3.7465 (14) A 0 ] and X—Y... π interactions to the thiophene and benzene rings [N... centroid distances = 3.718(3)A 0 and 3.355(3) A 0 , respectively]. Intermolecular C—H...O interactions link the molecules into chains parallel to the a axis (Fig.1). The length of the C11═N2 double bond is 1.268(3)A 0 . This value agrees well with the analogous bond reported elsewhere. [1,2].