Abdullah Aydın

3-Anilinomethyl-5-chloro-1,3-­benzoxazol-2(3H)-one

In the title compound, C14H11ClN2O2, the 2,3-dihydro-1,3-benzoxazole ring system is essentially planar [maximum deviation = 0.009 (2) Å] and makes a dihedral angle of 79.15 (7)° with the phenyl ring. Intermolecular N—H⋯O and weak C—H⋯Cl hydrogen bonds occur in the crystal structure.

2-{2-[4-(4-Fluoro-phen-yl)piperazin-1-yl]-2-oxoeth-yl}-6-(morpholin-4-yl)-4-phenyl-pyridazin-3(2H)-one.

In the title compound, C26H28FN5O3, the morpholine ring adopts a chair conformation. The piperazine ring is puckered [Q T = 0.5437 (15) Å, θ = 8.89 (15) and ϕ = 357.2 (11)°]. The 1,6-dihydropyridazine ring makes dihedral angles of 28.03 (7) and 77.46 (7)° with the phenyl and benzene rings, respectively. In the crystal, molecules are linked along the c axis by C—H⋯O interactions and are flattened parallel to the ac plane. C–H⋯π interactions also contribute to the stability of the structure.

4-[(2E)-2-(4-Chloro­benzyl­idene)hydrazinyl­idene]-1-methyl-1,4-dihydro­pyridine monohydrate

In the title compound, C13H12ClN3·H2O, the organic molecule is almost planar, with a dihedral angle of 3.22 (10)° between the benzene and pyridine rings. The crystal structure is stabilized by O—H⋯N and C—H⋯O hydrogen bonding and π–π stacking interactions [centroid–centroid distances = 3.630 (1) and 3.701 (1) Å].

Crystal Structure and Vibrational Spectra of 3-Chloro-4-Phenyl-6-(Morpholine-4-yl)-Pyridazine by Hartree-Fock and Density Functional Methods

The title compound, 3-chloro-4-phenyl-6-(morpholine-4-yl)-pyridazine (I), was prepared and characterized using elemental analysis and FT-IR and 1H NMR spectroscopy studies. The crystal and molecular structure of the title compound was determined from single-crystal X-ray diffraction data. It crystallizes in the orthorhombic space group P212121, Z = 8 with a = 7.5743 (3) Å, b = 14.8922 (8) Å, c = 23.3472 (9) Å, V = 2633.5 (2) Å3, and Dx = 1.391 Mg/m3. The title compound, C14H14ClN3O, crystallizes with two independent molecules A and B in the asymmetric unit, wherein the morpholine ring adopts a distorted chair conformation. The 1,6-dihydropyridazine ring creates dihedral angles of 47.0(3)° (in molecule A) and 47.9(2)° (in molecule B) with the phenyl ring, respectively. The crystal studied was an inversion twin with a 0.56(12):0.44(12) domain ratio. The molecular structure, vibrational frequencies, and intensities of the title compound were calculated using Hartree-Fock and density functional theory methods (BLYP, B3LYP, B3PW91, and mPW1PW91) using the 6-31G(d,p) basis set. The calculated geometric parameters were compared to the corresponding single crystal X-ray structure of the title compound. Comparison of the theoretical and experimental geometries of the title compound show that the X-ray parameters are in good agreement with the optimized molecular structure of the title compound. In addition, the harmonic vibrations computed for this compound using the B3LYP/6-31G(d,p) method are in good agreement with the observed vibrational spectral data. Theoretical vibrational spectra of the title compound were interpreted using PEDs and the VEDA 4 program. The superior performance of these investigated methods was calculated using the PAVF 1.0 program.

Crystal structure of 4-(4-chloro-phen-yl)-6-(morpholin-4-yl)pyridazin-3(2H)-one.

In the crystal, pairs of centrosymmetrically related molecules are linked into dimers via N—H⋯O hydrogen bonds, forming (8) ring motifs. The dimers are connected via C—H⋯O and C—H⋯Cl hydrogen bonds, forming a three-dimensional network·Semi-empirical molecular orbital calculations were carried out using the AM1 method.

2-[2-(4-Benzyl­piperazin-1-ylcarbon­yl)eth­yl]-5,6-diphenyl­pyridazin-3(2H)-one

The title compound, C30H30N4O2, has a non-planar conformation, the dihedral angles formed by the pyridazinone ring plane and the three phenyl rings being 54.61 (7), 51.10 (7) and 59.53 (8)°. The piperazine ring adopts a chair conformation. Inter- and intramolecular C—H⋯O contacts are found in the crystal structure and these consolidate the three-dimensional packing.

Crystal Structure and Theoretical Study of N,N-di[(5-chloro-2-oxo-2,3-dihydrobenzo[d]oxazole-3-yl)methyl]ethanamine

The aim of the present work is to explore crystal and electronic structure of N,N-di[(5-chloro-2-oxo-2,3-dihydrobenzo[d]oxazole-3-yl)methyl]ethanamine. In the title compound, C18H15Cl2N3O4, the two 2, 3-dihydro-1, 3-benzoxazole ring systems are almost planar and make a dihedral angle of 96.12(7) with each other. The ethyl group is disordered over two set of sites with a site-occupancy ratio of 0.766(12):0.234(12). The crystal structure contain intermolecular C—H...O hydrogen bonds which form a zigzag chains along the c-axis, C—H...π interactions and π-π stacking interactions [centroid-centroid distance = 3.5668(19) A].

Crystal structure of 4-[5-(4-fluorophenyl)-3-(4-hydroxyphenyl)-4,5-dihydropyrazol-1-yl] benzenesulfonamide, C21H18FN3O3S

Abstract C21H18FN3O3S, monoclinic, P 21 (no. 4), a = 11.6665(3) Å, b = 5.7483(2) Å, c = 14.7695(4) Å, α = 90°, β = 103.841(1)°, γ = 90°, V = 961.72(5) Å3, Z = 2, Rgt(F) = 0.0340, wRref(F2) = 0.0852, T = 296(2) K.

Crystal structure of 1-{4-hy-droxy-3-[(pyrrolidin-1-yl)meth-yl]phen-yl}-3-phenyl-prop-2-en-1-one.

In the title compound, the pyrrolidine ring adopts an envelope conformation, which may be correlated with the intramolecular O—H⋯N hydrogen bond.

Synthesis and Crystal Structure of 3-Amino-1-(5-Chloro-2-Hydroxyphenyl)Imidazolidine-2,4-Dione

The present study describes the synthesis, spectral data, and single crystal X-ray structural analysis of 3-amino-1-(5-chloro-2-hydroxyphenyl)imidazolidine-2,4-dione. X-Ray analysis revealed that the title compound did not have the anticipated structure, but had that of a different substance. This unexpected conformation generated the interest in studying the synthesis of this compound. The inspected compound, 3-amino-1-(5-chloro-2-hydroxyphenyl)imidazolidine-2,4-dione, is a pharmaceutical intermediate and is nonplanar. Its benzene and five-membered rings have a dihedral angle of 53.95(7)°. The conformation is stabilized by intermolecular O‒H … O, O‒H … N, and N‒H … O interactions and a weak C‒H … π interaction.