Search results for "Pyridine"

Synthesis and characterization of vanadyl(IV) complexes of Schiff bases derived from anthranilic acid and salicylaldehyde (or its derivatives) or ace…

1997

Anhydrous, dimeric vanadyl(IV) complexes of Schiff bases derived from [1+1] condensation of salicylaldehyde (or its derivatives) and anthranilic acid, have been synthesized from CH3CN and were characterized by elemental analysis, FTIR, EPR, absorption, TGA, cyclic voltammetry and room temperature magnetic susceptibility measurements. These complexes were found to be oxidized by air in polar solvents like MeOH and DMF to V-V products. The E(1/2) values were found to be around 660 mV indicating that the carboxylate group favours vanadyl(IV) binding when compared to the alkoxo-bound vanadium complexes. Oxidative instability of these complexes are dependent on the substituent on the salicylalde…

Dimensionally controlled hydrogen-bonded nanostructures: synthesis, structure, thermal and magnetic behaviour of the tris-(chelated)nickel(II) comple…

2002

Abstract Single crystals of the compound of formula [Ni(bipy)3]Cl2·5.5H2O (bipy=2,2′-bipyridine) have been prepared and structurally characterised by X-ray diffraction. The structure analysis reveals that the complex has an approximate D3 symmetry. The coordination sphere consists of six nitrogen atoms of the three-bipyridine ligands in an octahedral arrangement about the nickel. One of the chlorine ions is surrounded by twelve CH⋯Cl hydrogen bonds. Three kinds of layers are found in the crystal structure: (i) the Λ-[Ni(bipy)3]2+ cation; (ii) the water/chloride positions (O(1w)/Cl(21) to O(7w)/Cl(27)); (iii) the Δ-[Ni(bipy)3]2+ cation and a chloride ion (Cl(1)). The layers are stacked in t…

Molecular, Supramolecular Structures Combined with Hirshfeld and DFT Studies of Centrosymmetric M(II)-azido {M=Ni(II), Fe(II) or Zn(II)} Complexes of…

2021

The supramolecular structures of the three metal (II) azido complexes [Fe(4bzpy)4(N3)2]

Retraction notice to “trans-Tetrakis(pyridine)dichloroiron(II) as catalyst for Suzuki cross-coupling in ethanol and water” [Tetrahedron Lett. 49 (200…

2009

Spin Cross-Over (SCO) Complex Based on Unsymmetrical Functionalized Triazacyclononane Ligand: Structural Characterization and Magnetic Properties

2019

International audience; The unsymmetrical ligand 1-(2-aminophenyl)-4,7-bis(pyridin-2-ylmethyl)-1,4,7-triazacyclononane (L6) has been prepared and characterized by NMR spectroscopy. The L6 ligand is based on the triazamacrocycle (tacn) ring that is functionalized by two flexible 2-pyridylmethyl and one rigid 2-aminophenyl groups. Reaction of this ligand with Fe(ClO4)2·xH2O led to the complex [Fe(L6)](ClO4)2 (1), which was characterized as the first Fe(II) complex based on the unsymmetrical N-functionalized tacn ligand. The crystal structure revealed a discrete monomeric [FeL6]2+ entity in which the unsymmetrical N-functionalized triazacyclononane molecule (L6) acts as hexadentate ligand. As …

Metallophilic interactions in polymeric group 11 thiols

2016

Three polymeric group 11 transition metal polymers featuring metallophilic interactions were obtained directly via self-assembly of metal ions and 4-pyridinethiol ligands. In the cationic [Cu2(S-pyH)4]n2+ with [ZnCl4]n2− counterion (1) and in the neutral [Ag(S-py) (S-pyH)]n (2) 4-pyridinethiol (S-pyH) and its deprotonated form (S-py) are coordinated through the sulfur atom. Both ligands are acting as bridging ligands linking the metal centers together. In the solid state, the gold(I) polymer [Au(S-pyH)2]Cl (3) consists of the repeating cationic [Au(S-pyH)2]+ units held together by aurophilic interactions. Compound 1 is a zig-zag chain, whereas the metal chains in the structures of 2 and 3 a…

Bis[3-methyl-5-(pyridin-2-yl)-1H-pyrazol-4-yl] selenide methanol hemisolvate

2014

The asymmetric unit of the title compound, C18H16N6Se·0.5CH3OH, contains two independent molecules of bis[3-methyl-5-(pyridin-2-yl)-1H-pyrazol-4-yl] selenide with similar C—Se—C bond angles [99.30 (14) and 98.26 (13)°], and a methanol molecule of solvation. In one molecule, the dihedral angles between pyrazole and neighbouring pyridine rings are 18.3 (2) and 15.8 (2)°, and the corresponding angles in the other molecule are 13.5 (2) and 8.3 (2)°. In the crystal, the selenide and solvent molecules are linked by classical O—H...N and N—H...N hydrogen bonds, as well as by weak C—H...O and C—H...π interactions, forming a three-dimensional supramolecular architecture.

Self-assembled hydrogen-bonded coordination networks in two copper(II) carboxylates with 4-pyridylmethanol

2011

AbstractThe crystal and molecular structure of [Cu(nif)2(4-PM)2]·CH3OH (1) and [Cu(2-Clbz)2(4-PM)2(H2O)] (2), (where nif = niflumate anion, 2-Clbz = 2-chlorobenzoate anion and 4-PM is the 4-pyridylmethanol), have been determinated by X-ray crystallography. The Cu2+ cation in (1), is coordinated by two pairs of oxygen atoms from asymmetric bidentate niflumate anions and by a pair of pyridine nitrogen atoms from monodentate 4-pyridylmethanol ligands in trans position forming an extremely elongated bipyramid. The Cu2+ cation in (2), is coordinated by a pair of oxygen atoms from monodentate 2-chlorobenzoate anions, further by a pair of pyridine nitrogen atoms from monodentate 4-pyridylmethanol …

3-(4-Fluorophenyl)-6-methoxy-2-(4-pyridyl)quinoxaline

2009

In the title compound, C20H14FN3O, the quinoxaline system makes dihedral angles of 32.38 (7) and 48.04 (7)° with the 4-fluorophenyl and pyridine rings, respectively. The 4-fluorophenyl ring makes a dihedral angle of 57.77 (9)° with the pyridine ring. In the crystal, the molecules form dimeric C—H...N hydrogen-bonded R22(20) ring motifs lying about crystallographic inversion centers. The dimeric units stack via π–π interactions between methoxyphenyl rings and pyridine–fluorophenyl rings with centroid–centroid distances of 3.720 (1) and 3.823 (1) Å, …

1-[2-(Benzyl­amino)-4-pyrid­yl]-2-(4-fluoro­phen­yl)ethane-1,2-dione

2009

The crystal structure of the title compound, C20H15FN2O2, contains two crystallographically independent molecules, which are related by a pseudo-inversion center and linked into dimersviaintermolecular N—H...N hydrogen bonds. The 4-fluorophenyl ring of moleculeAmakes dihedral angles of 17.17 (16) and 62.25 (15)°, respectively, with the phenyl and pyridine rings. The 4-fluorophenyl ring of moleculeBmakes dihedral angles of 8.50 (16) and 64.59 (15)°, respectively, with the phenyl and pyridine rings. The dihedral angle between the pyridine ring and the phenyl ring of moleculeA[60.97 (15)°] is bigger than in moleculeB[59.49 (15)°]. The dihedral angle between the two pyridine rings is 1.37 (14)°…