Synthesis and spectroscopic characterizations of manganese(II), iron(III), copper(II) and zinc(II) hydrazine complexes as catalytic activity agents

ABSTRACT. This article deals with the preparation and coordination of NH2—NH2 hydrazine molecule compounds. The hydrazine sulfate complexes of Mn(II), Fe(III), Cu(II), and Zn(II) were prepared. These complexes were characterized by elemental, infrared, conduction, electron absorption spectroscopy, magnetic susceptibility, thermogravimetric analyses, X-ray powder diffraction (XRD) patterns and atomic force microscopy (AFM) studies. The magnetic measurements were confirmed that the Mn(II), Fe(III), Cu(II), and Zn(II) hydrazine complexes have an octahedral geometric structure. Thermogravimetric and its differential thermogravimetric analysis referred that all complexes passed through two-to-three thermal degradation steps with solid metal sulfate as a residual product. The infrared spectra inferred that the NH2—NH2 ligand forms complexes through nitrogen atoms of the—NH2 moiety, while the elemental analysis indicates [M(NH2—NH2)3]SO4 (where M = Mn(II), Cu(II), and Zn(II)) while the iron(III) complexes have the [Fe2(NH2—NH2)4(SO4)2]SO4 formula of coordination compounds, NH2—NH2 acts as a double bond. Both XRD and AFM analysis deduced that the synthesized hydrazine metal complexes were found to be in nano scale range 10—30 nm.                 KEY WORDS: Hydrazine, FTIR, AFM, XRD, Transition metals Bull. Chem. Soc. Ethiop. 2022, 36(1), 33-44.                                                                    DOI:   https://dx.doi.org/10.4314/bcse.v36i1.4                                                    &nbsp

A new simple route for synthesis of cadmium(II), zinc(II), cobalt(II), and manganese(II) carbonates using urea as a cheap precursor and theoretical investigation

ABSTRACT. The MnCO3.H2O, CoCO3.4H2O, ZnCO3, and CdCO3, respectively, were synthesized through a new precise, easy pathway for the reaction of MnI2, CoI2, ZnI2, or CdI2 aqueous solutions with a cheap precursor-urea for 10 h at ~ 70 oC. The IR spectra of reaction products designate the presence of characteristic bands of ionic carbonate, CO32– and absence of the individual bands of urea. The (CO3)2- ion is planar and therefore, it belongs to the D3h symmetry. It is expected to display four modes of vibrations. The stretching vibrations of the type; n(C-O) is observed in the range of (1376-1503) cm-1 while another stretching vibration n(C-O) is observed in the region 1060-1079 cm-1. The out of plane of vibration d(OCO) is observed in the range of (833-866) cm-1 while, the angle deformation bending vibration d(OCO) appear in the range of (708-732) cm-1. The infrared spectra of metal carbonate, show that, this product clearly has an uncoordinated water. The band related to the stretching vibration n(O-H) of uncoordinated H2O is observed as expected in the range of ~ 3000 cm-1. A general mechanism explaining the synthesis of carbonate compounds of cadmium(II), zinc(II), cobalt(II), and manganese(II), are described. Moreover, the DFT outcomes using B3LYP/LanL2DZ (basis set) agree with the experimental results.                 KEY WORDS: Carbonate, CoI2, Infrared spectra, Urea, DFT   Bull. Chem. Soc. Ethiop. 2022, 36(2), 363-372.                                                                DOI: https://dx.doi.org/10.4314/bcse.v36i2.10                                                     &nbsp

Thermal atomic layer deposition of aluminum oxide, nitride, and oxynitride: A mechanistic investigation

Atomic layer deposition (ALD) has been proven to be a versatile method for the deposition of thin films of various materials. It yields films with exceptional conformality and allows tunable film compositions with control of film thickness at the atomic level. Thin films of Al oxide, nitride, and oxynitride are deposited via ALD using Al(CH3)3 (TMA)/AlCl3 with H2O/NH3. Herein, surface chemical reactions are examined using density functional theory calculations to elucidate the adsorption, oxidation, and nitridation of precursors [TMA and AlCl3] as well as the mechanism controlling the composition of Al oxynitride thin films obtained through ALD. The hydrogen-terminated substrate surface is transformed into a CH3/Cl-terminated surface after the reaction with the TMA/AlCl3 precursors. The molecular adsorption of TMA occurs through a spontaneous reaction, whereas that of AlCl3 requires a slight energy input. Although the adsorption energy of AlCl3 is higher than that of TMA, the activation energy and energy change of AlCl3 adsorption are higher and lower than those of TMA, respectively; furthermore, the use of AlCl3 results in the generation of a corrosive by-product (HCl). A similar tendency is observed in the second ALD half reaction, which is oxidation. Nitride formation is endothermic for molecularly adsorbed AlCl3 but exothermic for TMA. Furthermore, the investigation of the exchange reactions between surface moieties and excess gaseous reactants reveals a preference for the substitution of N by O, which is attributed to differences in bond energies between the surface moieties and the surface metal atom, as well as between H2O and NH3

Exploring the effectiveness of flavone derivatives for treating liver diseases: Utilizing DFT, molecular docking, and molecular dynamics techniques

In exploring nature's potential in addressing liver-related conditions, this study investigates the therapeutic capabilities of flavonoids. Utilizing in silico methodologies, we focus on flavone and its analogs (1–14) to assess their therapeutic potential in treating liver diseases. Molecular change calculations using density functional theory (DFT) were conducted on these compounds, accompanied by an evaluation of each analog's physiochemical and biochemical properties. The study further assesses these flavonoids' binding effectiveness and locations through molecular docking studies against six target proteins associated with human cancer. Tropoflavin and taxifolin served as reference drugs. The structurally modified flavone analogs (1–14) displayed a broad range of binding affinities, ranging from -7.0 to -9.4 kcal mol⁻¹, surpassing the reference drugs. Notably, flavonoid (7) exhibited significantly higher binding affinities with proteins Nrf2 (PDB:1 × 2 J) and DCK (PDB:1 × 2 J) (-9.4 and -8.1 kcal mol⁻¹) compared to tropoflavin (-9.3 and -8.0 kcal mol⁻¹) and taxifolin (-9.4 and -7.1 kcal mol⁻¹), respectively. Molecular dynamics (MD) simulations revealed that the docked complexes had a root mean square deviation (RMSD) value ranging from 0.05 to 0.2 nm and a root mean square fluctuation (RMSF) value between 0.35 and 1.3 nm during perturbation. The study concludes that 5,7-dihydroxyflavone (7) shows substantial promise as a potential therapeutic agent for liver-related conditions. However, further validation through in vitro and in vivo studies is necessary.Key insights from this study include: • Screening of flavanols and their derivatives to determine pharmacological and bioactive properties using ADMET, molinspiration, and pass prediction analysis. • Docking of shortlisted flavone derivatives with proteins having essential functions. • Analysis of the best protein-flavonoid docked complexes using molecular dynamics simulation to determine the flavonoid's efficiency and stability within a system