Bis(3-acetyl-6-methyl-2-oxo-2H-pyran-4-olato)bis­(dimethyl sulfoxide)nickel(II)

In the title compound, [Ni(C8H7O4)2{(CH3)2SO}2], the NiII atom is located on a crystallographic centre of symmetry and has a distorted octa­hedral coordination geometry of type MO6. The bidentate dehydro­acetic acid (DHA) ligands occupy the equatorial plane of the complex in a trans configuration, and the dimethyl sulfoxide (DMSO) ligands are weakly coordinated through their O atoms in the axial positions

Synthesis, X-ray crystal structures, electrochemistry and theoretical investigation of a tetradentate nickel and copper Schiff base complexes

International audienceNew tetradentate mononuclear nickel(II) [NiL] and pentadentate binuclear copper(II) [Cu 2 L 2 H 2 O], H 2 O Schiff base complexes have been synthesized. The crystal structures of [NiL] and [Cu 2 L 2 H 2 O], H 2 O have been determined by X-ray diffraction method showing distorted square-planar geometry for [NiL] and distorted tetragonal pyramid geometry for [Cu 2 L 2 H 2 O], H 2 O. In both complexes, the dehydroacetic acid functional group engages in a deprotonated manner and coordination occurs through the nitrogen atoms of the imine function and the phenolic oxygen. Density Functional Theory calculations are carried out for the determination of the optimized structures. The fundamental vibrational wave numbers are calculated and a good agreement between observed and calculated wave numbers is achieved

Crystal structure and spectral of new hydrazine-pyran-dione derivative: DFT enol↔hydrazone tautomerization via zwitterionic intermediate, hirshfeld analysis and optical activity studies

A novel functionalized Schiff base derivative, (E)-3-(1-(2-(9H-fluoren-9-ylidene)hydrazineyl)ethylidene)-6-methyl-2H-pyran-2,4(3H)-dione, was synthesized via subsequent condensation/tautomerization processes in a high yield. The product was fully characterized using NMR, FT-IR, and single-crystal XRD; the results of DFT simulations were in respectable agreement with crystallographic data. To elucidate the isomerization, the enol↔hydrazinium tautomerism has been pursued theoretically, suggesting an intramolecular single proton transfer (SPT) from enol (O ….H) to the closest NC unit, giving the hydrazine (N–H) via [N+—H ….O−] S (6) zwitterionic intermediate. The results of Hirshfeld surface analysis (HSA) and Molecular electronic potential (MEP) were matching the experimental XRD results. Since a number of hydrogen bonding groups, C–H …. π, and π …. π-stacking interactions were detected experimentally. The optical properties of the desired compound were experimentally and theoretically figure out.The authors acknowledge the Algerian Directorate General for Scientific Research and Technological Development and the Algerian Ministry of Higher Education and Scientific Research, for support of this work. Researchers Supporting Project (RSP-2020/78), King Saud University, Riyadh, Saudi Arabia

Crystal structure of (E)-1-[4-({4-[(4-methoxybenzylidene)amino]phenyl}sulfanyl)phenyl]ethan-1-one

The title Schiff base compound, C22H19NO2S, crystallized with two independent molecules (A and B) in the asymmetric unit. Both molecules have an E conformation about the C=N bond. The two molecules differ in the orientation of the aromatic rings with respect to each other. The outer 4-methoxybenzene ring is inclined to the central benzene ring and the outer 4-acetylbenzene ring by 1.80 (19) and 63.73 (19)°, respectively, in molecule A, and by 6.72 (18) and 68.53 (19)°, respectively, in molecule B. The two outer benzene rings are inclined to one another by 63.77 (18) and 63.19 (18)° in molecules A and B, respectively. In the crystal, the individual molecules stack in columns along [010], and are linked by a number of C—H...π interactions, forming slabs lying parallel to (001)

Crystal structure of (E)-4-hydroxy-3-{1-[(4-hydroxyphenyl)imino]ethyl}-6-methyl-2H-pyran-2-one

In the title Schiff base, C14H13NO4, which adopts the phenol–imine tautomeric form, the dihedral angle between the planes of the benzene and heterocyclic (r.m.s. deviation = 0.037 Å) rings is 53.31 (11)°. An intramolecular O—H...N hydrogen bond closes an S(6) ring. In the crystal, molecules are linked by O—H...O hydrogen bonds to generate C(11) chains propagating in the [010] direction. A weak C—H...O link is also observed, leading to the formation of R55(32) rings extending parallel to the (101) plane

Cobalt(II), Nickel(II) and Zinc(II) complexes based on DHA: Synthesis, X-ray crystal structure, antibacterial activity and DFT computational studies

International audienceIn the present work, a combined experimental and computational study of three new DHA chelates namely [Co(DHA)2.2DMSO] (1), [Ni(DHA)2.2DMF] (2) and [Zn (DHA)2.2DMF] (3), (DHA = 3-Acetyl-4-hydroxy-6-methyl-2-oxo-2H-pyran) is reported. Synthesized compounds are characterized by FT-IR which indicates the metal coordination via both oxygen atom, while single-crystal X-ray crystallography confirms the chelates structure as mononuclear complexes having a distorted octahedral coordination geometry of type MO6 with intermolecular C–H⋯O bonds. Structures and electronic properties investigated in the framework of the density functional theory (DFT) are in good agreement with experimental results. Besides, a comparative evaluation of in vitro antibacterial potential of DHA and derivatives exhibits better results for DHA free ligand, even close to the effect of antibiotics used as references, highlighting the role of hydroxyl function in case of this application

(E)-4-Hydroxy-6-methyl-3-[1-(2-phenylhydrazinylidene)ethyl]-2H-pyran-2-one

The title compound, C14H14N2O3, crystallized with three crystallographically independent molecules (A, B and C) in the asymmetric unit. The three molecules each have an E conformation about the C=N bond but differ in the orientation of the phenyl and pyran rings. The dihedral angles between the phenyl and pyran ring planes are 14.30 (1), 28.38 (1) and 25.58 (1)° in molecules A, B and C, respectively. There is an intramolecular O—H...N hydrogen bond in each molecule with an S(6) ring motif. In the crystal, molecules are linked by N—H...O and C—H...O hydrogen bonds, forming layers parallel to (001), enclosing R22(8) and R33(21) ring motifs. The layers are linked via C—H...π interactions, forming bilayers, which are joined by a further C—H...π interaction, forming a three-dimensional structure

Diaquabis[4-(dimethylamino)pyridine-κN1]bis[2-(1,3-dioxo-2,3-dihydro-1H-isoindol-2-yl)acetato-κO1]cobalt(II)

In the mononuclear title complex, [Co(C10H6NO4)2(C7H10N2)2(H2O)2], the CoII ion is located on an inversion centre and has a distorted octahedral coordination geometry of type CoN2O4 by two N atoms from the two 4-(dimethylamino)pyridine (DMAP) ligands, two carboxylate O atoms from the two deprotonated N-phthaloylglycine (Nphgly) ligands [systematic name: 2-(1,3-dioxo-2,3-dihydro-1H-isoindol-2-yl)acetate] and two coordination water molecules. In the crystal, O—H...O, C—H...O hydrogen bonds and π–π stacking interactions link the molecules into the supramolecular structure

Synthesis, X-ray crystallography, computational studies and catecholase activity of new zwitterionic Schiff base derivatives

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Tautomerization of diazene<=>hydrazine via single proton tautomerization, spectral, XRD/HSA-interactions, optical and DFT/TD-DFT of new hydrazine ligand

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