Driss Eddike

Synthesis and X-Ray Structure of (N,N-Bis(3,5-dimethylpyrazol- 1-ylmethyl)-1-hydroxy-2-aminoethane)(3,5-dimethylpyrazole) copper(II) dinitrate

The tridentate ligand N,N-Bis(3,5-dimethylpyrazol-1-ylmethyl)-1-hydroxy-2-aminoethane (L) has been prepared in one step by condensation of two equivalents of 1-hydroxymethyl-3,5-dimethylpyrazole with one equivalent of 2-aminoethanol. This reaction is carried out under microwave irradiation (60 W) in the absence of solvent for 20 min [1]. Using this ligand L a new Cu(II) dinitrate complex has been prepared. The single-crystal X-ray structure of the title compound, [N,N-bis(3,5-dimethylpyrazol-1-ylmethyl)-1-hydroxy-2-aminoethane] (3,5-dimethylpyrazole)copper(II) dinitrate, revels that the copper (II) ion is coordinated to two pyrazole nitrogens, one tertiary amine nitrogen of the ligand L and 3,5-dimethylpyrazole, and in the apical position by an alcohol O atom.

β-Keto-enol Tethered Pyridine and Thiophene: Synthesis, Crystal Structure Determination and Its Organic Immobilization on Silica for Efficient Solid-Liquid Extraction of Heavy Metals

Molecules bearing β-keto-enol functionality are potential candidates for coordination chemistry. Reported herein is the first synthesis and use of a novel designed ligand based on β-keto-enol group embedded with pyridine and thiophene moieties. The product was prepared in a one-step procedure by mixed Claisen condensation and was characterized by EA, m/z, FT-IR, (1H, 13C) NMR and single-crystal X-ray diffraction analysis. The new structure was grafted onto silica particles to afford a chelating matrix which was well-characterized by EA, FT-IR, solid-state 13C-NMR, BET, BJH, SEM and TGA. The newly prepared organic-inorganic material was used as an adsorbent for efficient solid-phase extraction (SPE) of Cu(II), Zn(II), Cd(II) and Pb(II) from aqueous solutions and showed a capture capacity of 104.12 mg·g−1, 98.90 mg·g−1, 72.02 mg·g−1, and 65.54 mg·g−1, respectively. The adsorption capacity was investigated, in a batch method, using time of contact, pH, initial concentration, kinetics (Langmuir and Freundlich models), and thermodynamic parameters (ΔG°, ΔH° and ΔS°) of the system effects.

Synthesis, characterisation and crystal structure of a new bis-tripodal ligand : N,N,N,N'-tetrakisl(1,5-dimethylpyrazol-3-yl)methyl ]- 1,4-phenylenediamine

The synthesis of a new bis-tripodal ligand N,N,N′,N′-tetrakis[(1,5-dimethylpyrazol-3-yl)methyl]-1,4-phenylenediamine is reported and clearly established from its spectroscopic data (IR, 1H NMR, mass spectrometry) and elemental analysis. The X-ray structure of the target compound has been determined and the pyrazolyl ligand crystallises in the space group P-1 [C30H40N10; a = 7.1533(7)Å; b = 9.7541(10)Å; c = 10.7169(10)Å; α = 94.420(8)°; β = 97.920(8)°; γ = 108.088(9)°, Z = 2].

A redetermination of [N,N-bis(3,5-dimethyl-1H-pyrazol-1-ylmethyl-κN2)-2-hydroxyethyl­amine-κN](3,5-dimethyl-1H-pyrazole-κN2)nitratocopper(II) nitrate

The new crystal structure analysis of the title compound, [Cu(NO3)(C5H8N2)(C14H23N5O)]NO3, reveals that the copper(II) ion lies in a distorted octahedral environment, with four N atoms in the equatorial plane and two O atoms at the axial positions. The O atoms of the nitrate group are involved in intra- and intermolecular hydrogen bonding.

1,1′-Bis­(2-nitro­phen­yl)-5,5′-dipropyl-3,3′-bipyrazole

In the title compound, C24H24N6O4, the two pyrazole rings are essentially coplanar, with a dihedral angle of 2.8 (3)°.

X-ray Single Crystal Structure, DFT Calculations and Biological Activity of 2-(3-Methyl-5-(pyridin-2’-yl)-1H-pyrazol-1-yl) Ethanol

A pyridylpyrazole bearing a hydroxyethyl substituent group has been synthesized by condensation of (Z)-4-hydroxy-4-(pyridin-2-yl)but-3-en-2-one with 2-hydroxyethylhydrazine. The compound was well characterized and its structure confirmed by single crystal X-ray diffraction. Density functional calculations have been performed using DFT method with 6-31G* basis set. The HOMO-LUMO energy gap, binding energies and electron deformation densities are calculated at the DFT (BLYP, PW91, PWC) level. The electrophilic f(−) and nucleophilic f(+) Fukui functions and also the electrophilic and nucleophilic Parr functions are well adapted to find the electrophile and nucleophile centers in the molecule. The title compound has been tested for its DPPH radical scavenging activity which is involved in aging processes, anti-inflammatory, anticancer and wound healing activity. Compound is also found with a significant antioxidant activity, probably due to the ability to donate a hydrogen atom to the DPPH radical.

Engineering β-ketoenol structure functionality in hybrid silica as excellent adsorbent material for removal of heavy metals from water

Chelating adsorbents, based on the chemical modification of silica by an efficient host able to capture toxic metals, are the most popular materials for wastewater treatment. Herein, a novel inorganic–organic hybrid material incorporating a β-keto–enol bis-heterocycle structure (SiNPz-Fn) was synthesized and the structure of the host was confirmed by single crystal X-ray diffraction. This ligand was designed to introduce active lone-pair donor systems on the silica surface. The new material has been characterized using a set of suitable physical techniques, and was found to be an efficient adsorbent for Pb(II), Zn(II), Cu(II) and Cd(II) from aqueous solution. The influence of the solution pH, contact time, initial concentration, temperature, thermodynamics and co-existing interferent substances was also studied. The adsorption kinetics of Pb(II), Zn(II), Cu(II) and Cd(II) onto SiNPz-Fn can be well fitted with a pseudo-second-order model and the adsorption capacity of this material is evaluated as 87.71, 54.64, 28.81 and 10.77 mg g−1 for Pb(II), Zn(II), Cu(II) and Cd(II), respectively. An endothermic and spontaneous process was identified. The new material was used for the extraction of metals from natural water and promises good recyclability for at least five cycles, showing great potential in practical applications.

Crystal structure of (Z)-1-(1,5-dimethyl-1H-pyrazol-3-yl)-3-(4-ethoxyphenyl)-3-hydroxyprop-2-en-1-one, C16H18N2O3

Abstract C16H18N2O3, orthorhombic , Pca21 (no. 29), a = 14.3074(1) Å, b = 8.5321(1)Å, c = 12.2534(2)Å, V = 1495.8(4)Å3, Z = 4, Rgt(F) = = 0.071, wRref(F2) = 0.1266, T = 302 K.

Crystal structure of (Z)-1-(1,5-dimethyl-1H-pyrazol-3-yl)-3-hydroxy-3-(4-methoxyphenyl)prop-2-en-1-one, C15H16N2O3

Abstract C15H16N2O3, monoclinic, P21/c (no. 14), a = 11.223(2) Å, b = 11.9339(5) Å, c = 11.945(2) Å, β = 117.43(2)°, V = 1419.9(5) Å3, Z = 4, Rgt(F) = 0.0528, wRref(F2) = 0.1346, T = 300(2) K.

Crystal structure of (Z)-1-(1,5-dimethyl-1H-pyrazol-3-yl)-3-hydroxy-3-(p-toly)prop-2-en-1-one, C15H16N2O2

Abstract C14H14N2O2, orthorhombic, P212121 (no. 19), a = 5.6736(2) Å, b = 7.7803(4) Å, c = 28.7821(13) Å, V = 1270.5(1) Å3, Z = 4, Rgt(F) = 0.0454, wRref(F2) = 0.0879, T = 298 K.