Synthesis, Structure, Thermal Decomposition and Computational Calculation of Heterodinuclear NiII - ZnII Complexes.

Mononuclear NiL complex was prepared by the use of bis-N,N'-salicylidene-1,3-propanediamine and Ni(II) salts. NiL was treated with ZnBr2 and pyrazole and 3,5-lutidine coligands in a dioxane medium to prepare the following diheteronuclear complexes: [NiL·ZnBr2·(pyrazole)2] and [NiL·ZnBr2·(3,5-lutidine)2]. The complexes were characterized by elemental analysis, TG, IR and mass spectrometry. The effects of heterocyclic one- and two- nitrogen atoms containing co-ligands were also examined. Theoretical formation enthalpies, dipole moments and the relative levels of HOMO and LUMO energies were determined by the use of Gaussian09 program. The occupancy levels of the atomic orbitals were determined by the NBO analysis of Gaussian09. The effect of pyrazole and lutidine upon the complex formation was evaluated by the use of X-ray diffraction, TG and theoretical calculations. NiL complex with lutidine forms a square pyramidal conformation since lutidine is a much stronger coligand than pyrazole.

Some Nitrogen Rich Energetic Material Synthesis by Nucleophilic Substitution Reaction from Polynitro Aromatic Compounds.

Three new nitrogen-rich energetic compounds, N-(5-chloro-2,4-dinitrophenyl)hydrazine (1), N-(5-chloro-2,4-dinitrophenyl)guanidine (2) and N-(5-chloro-2,4-dinitrophenyl)-4-aminopyrazole (3) prepared by the nucleophilic substitution reaction of 1,3-dichloro-4,6-dinitrobenzene with hydrazine, guanidinium carbonate and 4-aminopyrazole. The compounds were characterized by 1H NMR, 13C NMR, IR and mass spectroscopy. Only compound 2 could be prepared in a suitable crystal and molecular model was determined by X-ray analysis. Compounds were investigated by TG and DSC. Thermal degradation and thermokinetic behavior were investigated by Ozawa-Flynn-Wall and Kissinger-Akahira-Sunose techniques. Compounds were observed to be prone to exothermical thermal decomposition. HOMO and LUMO levels, theoretical formation enthalpy and electrostatic maps were calculated by Gaussian09. The detonation velocity and pressure were calculated by Kamlet-Jacobs equation. The compounds were assayed for antimicrobial properties.

Amperometric biogenic amine biosensors based on Prussian blue, indium tin oxide nanoparticles and diamine oxidase- or monoamine oxidase-modified electrodes.

Biogenic amine biosensors, based on screen-printed carbon electrodes (SPCE) modified with Prussian blue (PB) and indium tin oxide nanoparticles (ITONP), are reported. PB/ITONP-modified SPCE was further modified with diamine oxidase (DAO) or monoamine oxidase (MAO) enzymes to construct the biosensors. The morphology of the modified electrodes was studied by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and atomic force microscopy (AFM). Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to enlighten the electrochemical properties of the modified electrodes at each step of biosensor fabrication. Electrode surface composition and experimental conditions were optimized and analytical performance characteristics of the biosensors were studied. Several biogenic amines were tested and both biosensors responded to histamine, putrescine and cadaverine. DAO/ITONP/PB/SPCE biosensor exhibited the highest response to histamine 6.0 × 10-6-6.9 × 10-4 M with a sensitivity of 1.84 µA mM-1. On the other hand, the highest sensitivity was obtained for cadaverine with the MAO/ITONP/PB/SPCE biosensor. The analytical utility of the presented biosensors were illustrated by the determination of cadaverine and histamine in cheese sample.