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Three aromatic imines derived from ortho-amino and para-amino benzaldehyde with suitable primary amine were synthesized by standard methods. These resulted to the formation of one oxime compound and two Schiff bases which were named Syn-ortho-aminobenzaldoxime, ortho-aminobenzylidinaniline and para-aminobenzylidin-para-chloroaniline respectively. The structures of these imines were certain by physical methods as outlined in another paper under publication. The main aim of project was the determination of ionization constants pKa for acid conjugate bases of imines under stud by potentiometric titration method using 0.1 M HCl as a titrant. These allowed the determination of ionization constant at range of temperatures (288-328) K, Hence the thermodynamic parameters of ionization, processes namely ΔG, ΔH and ΔS were evaluated and discussed. All the experimental results were complemented with theoretical calculations using density functional theory (DFT), various types of descriptors as parameters were based on quantum mechanical handlings. The parameters tested which have the capability to represent the changes observed in the experimental pKa(s) are atomic and structural properties included Molecular properties like energies of HOMO and LUMO, hardness(η), chemical potential(µ), ΔHf, , dipole of molecule(DM), and electrophilicity index(ω). The pKa investigated had a relation with the values of each parameter of the studied compounds. Depending on these relations, three sets of parameters were originated for comparison between the AM1, PM3, and HF6-311G methods. They were derived by employing semi-empirical calculation exemplified with AM1 and the PM3 model, and an Abinitio method expressed by Hartree-Fock (HF) model performed at the 6-311 G(d, p) level of theory. [ABSTRACT FROM AUTHOR]

Several Imines (Schiff bases) have been reported for their significant biological activity. In this work, an imine, (E)-1-(3-bromobenzylidene)-2-phenylhydrazine has been synthesized under microwave irradiation and evaluated for its antioxidant activity by DPPH assay. The structure of synthesized compound was confirmed based on the spectroscopic data included UV-Vis, FT-IR, MS, 1D and 2D NMR. Based on the DPPH assay, the synthesized compound possessed a strong antioxidant activity with IC50 value of 62 μg/ml. [ABSTRACT FROM AUTHOR]

Corrosion is inherent for mild steel and it can be retarded through many approaches including electrodeposition of inert inhibitors in the form of organic molecules. Salicylideneaniline (L1) and 4-hydroxybenzalaniline (L2) were electrodeposited on mild steel using cyclic voltammetry (CV) using 0.1 M inhibitor concentration in 0.3 M NaOH. The scanning potential range for coating via CV was set from 0 - 2 V and back to 0 V for five cycles. A yellow film was observed covering the surface of the mild steel. The corrosion behavior of coated and uncoated mild steel was studied using Linear Polarization Resistance (LPR) in 0.5 M NaCl. Both coated mild steel specimens showed better corrosion resistance than the uncoated, with L1 providing a better inhibition protection with the inhibition efficiency of 80.51%. [ABSTRACT FROM AUTHOR]

The Zn(II), Cd(II), Hg(II) complexes bearing diimine and one-dimensional (1D) push-pull NLO-phores with π-conjugation between ligands and metal have been synthesized for two-dimensional (2D) nonlinear optical response. The third-order nonlinear optical properties of complexes were studied using Z-scan technique at 532 nm with nanosecond laser pulses. The complexes show optical limiting behavior. The values of the effective two-photon absorption (2PA) coefficients (β), third-order nonlinear susceptibilities (χ((3)) and large two-photon absorption cross sections (σ2) are calculated. Z-scan results show that complexes are suitable materials for optical limiting as well as optical switching applications. [ABSTRACT FROM AUTHOR]