A sensitive and simple method for voltammetric analysis of Sudan I as an azo dye in food samples using a Fe3O4-ZIF-67/ionic liquid modified carbon paste electrode

The present studydeveloped a facile and fast electrochemicalapproach to sensitively analyze Sudan I using Fe3O4-ZIF-67 nanocomposite plus ionic liquid (IL). The carbon paste electrode (CPE) modified with Fe3O4-ZIF-67/IL exhibited an excellent electrochemical sensing performance to SudanI. Compared with the unmodified CPE, Fe3O4-ZIF-67/ILCPE could significantly increase the peak current of Sudan I oxidation and decrease the oxidation overpotentials. Under the best experimental conditions, the sensor using differential pulse voltammetry (DPV) technique responded to SudanI linearly (0.5 -560 μM) with a low limit of detection (LOD) of 0.1 μM. Additionally, the applicability and effectiveness of our proposed method in sensing Sudan I present in food samples was confirmed by acceptable recovery rate (96.0-103.6%)

Synthesis, characterization and X-ray structure of an oxazine derivative

The 5,6-dihydro-6-methyl-2,3-diphenyl-2H-1,4-oxazine-2-ol compound (2) was prepared unambiguously by condensation of 1,2-diphenylethanone with 1-amino-2-propanol in the presence of glacial acetic acid. The product was characterized by FT-IR, 1HNMR, UV-Vis spectroscopy and X-ray crystallography. Quantum chemical calculations are used to the proposed mechanism.  KEY WORDS: 1,2-Diphenylethanone, 1-Amino-2-propanol, Oxazine  Bull. Chem. Soc. Ethiop. 2010, 24(2), 283-287

Methanol{2-meth­oxy-6-[(2-oxidoprop­yl)imino­meth­yl]phenolato}dioxidomolyb­denum(VI)

In the structure of the title compound, [Mo(C11H13NO3)O2(CH3OH)], the MoVI ion is octahedrally coordinated by two oxide O atoms, the N atom and two deprotonated OH groups of the tridentate Schiff base ligand 2-meth­oxy-6-[(2-oxidoprop­yl)imino­meth­yl]phenolate and by a methanol O atom. In the crystal structure, two complexes are linked via O—H⋯O hydrogen bonds, yielding a centrosymmetric arrangement involving the methanol hydr­oxy group and one of the ligand O atoms coordinated to the MoVI ion

(E)-2-(5,5-Dimethyl­hexa­hydro­pyrimidin-2-yl)-4-(phenyl­diazen­yl)phenol

In the title Schiff base, C18H22N4O, the hexa­hydro­pyrimidinyl ring adopts a chair conformation. The dihedral angle between the aromatic rings of the 4-(2-phenyl­diazen­yl)phenol unit is 15.7 (1)°. There is an intra­molecular O—H⋯N hydrogen bond between the hydroxyl group and an N atom of the hexa­hydro­pyimidinyl unit. Inter­molecular N—H⋯O and N—H⋯N hydrogen bonds give rise to a layer structure

A new MoVI Schiff base complex: methanol[N′-(3-meth­oxy-2-oxidobenzyl­idene)benzohydrazidato]dioxido­molybdenum(VI)

In the title benzil­idene Schiff base molybdenum(VI) complex, [Mo(C15H12N2O3)O2(CH3OH)], the MoVI ion is coordinated by two oxide O atoms and by two O atoms and one N atom of the tridentate N′-(3-meth­oxy-2-oxidobenzyl­idene)benzo­hydrazidate (L) Schiff base ligand. The methanol O atom completes the distorted octa­hedral configuration of the MoVI atom. Strong O—H⋯N hydrogen bonds form a C(5) chain around a 21 screw axis. Weak C—H—O hydrogen bonds are also present

Methano­ldioxido{1-[(2RS)-(2-oxidoprop­yl)iminometh­yl]-2-naphtholato}molybdenium(VI)

Crystals of the title compound, [Mo(C14H13NO2)O2(CH4O)], were obtained by recrystallization from methanol. The MoVI atom is coordinated by two oxide O atoms and by two O atoms and one N atom of the tridentate 1-[(2-oxidoprop­yl)iminometh­yl]-2-naphtholate Schiff base ligand. The coordination sphere is completed by the O atom of a methanol mol­ecule, yielding a distorted octa­hedron. O—H⋯O hydrogen bonding yields centrosymmetric dimers

{1,1′-[(2,2-Dimethyl­propane-1,3-di­yl)bis­(nitrilo­methyl­idyne)]di-2-naphthol­ato}dioxidomolybdenum(VI) dichloro­methane 1.75-solvate

In the crystal structure of the title compound, [Mo(C27H24N2O2)O2]·1.75CH2Cl2, the MoVI ion is coordinated by two oxide O atoms and by two O and two N atoms of the tetra­dentate 1,1′-[(2,2-dimethyl­propane-1,3-di­yl)bis­(nitrilo­methyl­idyne)]di-2-naphtholate Schiff base ligand in a distorted octa­hedral configuration. The compound crystallizes with 1.75 mol­ecules of dichloro­methane per complex mol­ecule. In the crystal, symmetry-related mol­ecules are linked by a number of C—H⋯O inter­actions involving both the Schiff base ligand and the partly disordered dichloro­methane solvent mol­ecules, leading to the formation of a two-dimensional network extending parallel to (101)

Cis-Dioxido-molybdenum(VI) complexes of tridentate ONO hydrazone Schiff base: Synthesis, characterization, X-ray crystal structure, DFT calculation and catalytic activity

Two new cis-MoO₂ [MoO₂(L)(EtOH)] (1), [MoO₂(L) (Py)] (2) [L: (3-methoxy-2oxidobenzylidene)benzohydrazidato], complexes have been synthesized and fully characterized on the basis of elemental analysis, FT-IR, molar conductivity, ¹H NMR, ¹³C NMR and electronic spectra. The structure of complexes has been accomplished by single crystal X-ray diffraction. All experimental results confirmed that both complexes have an octahedral geometry around the Mo(VI) central atom, which is coordinated by the donor atoms of the dianionic hydrazone ligand, two oxido groups and oxygen/nitrogen atoms of solvent molecules. Computational studies were also performed using DFT calculations at B3LYP/DGDZVP level of theory. Furthermore, their catalytic activities were investigated on the electrophilic reaction of indole with aldehydes in molten tetrabutyl ammonium bromide (TBAB) to obtain bis(indolyl)methane derivatives

Synthesis, X-ray structure and DFT calculation of oxido-vanadium(V) complex with a tridentate Schiff base ligand

Reaction of 4-bromo-2-(((5-chloro-2-hydroxyphenyl) imino)methyl)phenol (H₂L) with VOSO₄·XH₂O generates the oxido-vanadium(V) complex [VOL(OCH₃)(OHCH₃)], that characterized by FT-IR, UV–Vis, and elemental analysis. The complex was also characterized by single crystal X-ray diffraction crystallography. A DFT calculation was carried out on the complex using the B3LYP/6-31+G(d,p) method. The agreement between the theoretical and experimental data is good. NBO data shows that the donation from donor atoms to the metal center is greater than back bonding

Dioxidobis{2-[(E)-p-tolyl­imino­meth­yl]phenolato}molybdenum(VI)

The asymmetric unit of the title compound, [Mo(C14H12NO)2O2], comprises half of the complex with the full mol­ecule generated by the application of twofold symmetry. The MoVI atom is surrounded by two oxide O atoms and the two sets of N,O-donor atoms of the bidentate Schiff base ligands. The resulting N2O4 donor set defines a distorted octa­hedral coordination geometry. Inter­molecular C—H⋯O contacts link mol­ecules into chains along the b axis. The crystal structure is further stabilized by inter­molecular π–π inter­actions [ring centroid–centroid distance = 3.724 (6) Å]