Yavuz Köysal

An experimental and DFT computational study on 4-(3-(1H-imidazol-1-yl)propyl)-5-methyl-2H-1,2,4-triazol-3(4H)-one monohydrate

The triazole compound 4-(3-(1H-imidazol-1-yl)propyl)-5-methyl-2H-1,2,4-triazol-3(4H)-one monohydrate has been synthesised and characterised by 1H-NMR, 13C-NMR, IR, and X-ray single-crystal determination. The compound crystallizes in the triclinic space group with a = 9.0366(7) Å, b = 11.5690(8) Å, c = 12.0571(9) Å, α = 110.733(6)°, β = 94.172(6)°, γ = 98.085(6)° and Z = 4. In addition to the molecular geometry from X-ray determination, the molecular geometry, vibrational frequencies and gauge, including atomic orbital (GIAO) 1H- and 13C-NMR chemical shift values of the title compound 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 optimised geometries can well reproduce the crystal structure, and the theoretical vibrational frequencies and chemical shift values show good agreement with experimental values. The energetic behaviour of the title compound in solvent media was examined using the B3LYP method with the 6-31G(d) basis set by applying the Onsager model. The total energy of the title compound decreases with increasing polarity of the solvent. The predicted nonlinear optical properties of the title compound are greater than those of urea. In addition, DFT calculations of the molecular electrostatic potentials, frontier molecular orbitals and thermodynamic properties of the title compound were carried out at the B3LYP/6-31G(d) level of theory.

Theoretical modeling and experimental studies on N-n-Decyl-2-oxo-5-nitro-1-benzylidene-methylamine

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.

Crystal structure, spectroscopic investigations and density functional studies of 4-(4-methoxyphenethyl)-5-benzyl-2H-1,2,4-triazol-3(4H)-one monohydrate.

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.

4-(2,3-Dihydroxybenzyl­ideneamino)-3-methyl-1H-1,2,4-triazol-5(4H)-one

All the non-H atoms of the title compound, C10H10N4O3, 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 molecule adopts the enol–imine tautomeric form with an intramolecular hydrogen-bonding interaction between the Schiff base N atom and the hydroxy group. In the crystal, intermolecular N—H⋯O and O—H⋯O hydrogen bonds link the molecules into a three-dimensional network.

Experimental and DFT computational studies on 5-benzyl-4-(3,4-dimethoxyphenethyl)-2H-1,2,4-triazol-3(4H)-one

The triazole compound, 5-benzyl-4-(3,4-dimethoxyphenethyl)-2H-1,2,4-triazol-3(4H)-one, has been synthesized and characterized by 1H-NMR, 13C-NMR, IR, and X-ray single-crystal determination. The compound crystallizes in the monoclinic space group P21 with a = 11.8844(3) Å, b = 17.5087(4) Å, c = 17.3648(6) Å, β = 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) 1H- and 13C-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.

Ethyl 4-(3-ethyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-4-yl)benzoate

In the title compound, C13H15N3O3, the dihedral angle between the two aromatic ring is 51.06 (1)°. In the crystal, molecules are connected by pairs of N—H⋯O hydrogen bonds into centrosymmetric dimers.

Crystal and molecular structure of (Z)-4-(((Z)-(2-oxonaphthalen-1(2H)-ylidene)methyl)amino)-N-(thiazol-2(3H)-ylidene)benzenesulfonamide

The experimental geometry of the title compound, (Z)-4-(((Z)-(2-oxonaphthalen-1(2H)-ylidene)methyl)amino)-N-(thiazol-2(3H)-ylidene)benzene, C20H15N3O3S2, was characterized by X-ray diffraction analysis (XRD). And also SEM analysis has been done for morphological investigation of the crystal structure. Molecular structure crystallizes in triclinic form, space group P

6-(2-Fluorobenzylidene)-2-[1-(2-fluoro-4-biphenyl)ethyl]thiazolo[3,2-b][1,2,4]triazol-5(6H)-one

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