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A tridentate Schiff base ligand HL(ATS), N-[2-acetylthiophene]salicylideneimine was derived from the 1 : 1 condensation of 2-acetyl thiophene and 2-aminophenol was prepared and characterized by elemental analysis, FT-IR, Mass, 1 H-NMR, UV-VIS, thermogravimetric analysis and fluorescence spectra. Cobalt(II) complex was obtained by the reaction of the Schiff base ligand (HL) with cobalt(II) hexahydrate in 1 : 1 molar ratio. The cobalt (II) complex have been characterized by elemental analysis, FT-IR, 1 H-NMR, Ms, UV-VIS, magnetic moment, molar conductance, thermogravimetric analysis (TGA) and fluorescence spectra. Elemental analysis (CHNS) data proved 1 : 1 (M : L) stoichiometry for the reported cobalt (II) complex. IR spectra showed that cobalt (II) complex was coordinated in metal ions via the imine N, O and S atoms. Magnetic and UV-VIS spectra, showed that the geometrical structure of cobalt(II) complex is an octahedral. The molar conductance data revealed that the cobalt(II) complex is non-electrolyte. Thermogravimetric analysis (TGA) revealed the high thermal stabilities.

Syntheses and physicochemical studies of Mn(II), Co(II), Ni(II) and Cu(II) complexes with tridentate Schiff base ligand (E)-2-((1-(thiophen-2-yl)ethylidene)amino)phenol (HL) (ATS) were characterized by elemental analysis, FT-IR, Mass, 1 H NMR, UV-Vis, magnetic moment, thermal analysis (TG and DTG) techniques, molar conductance and fluorescence spectra. The IR spectra showed that complexes were coordinated in metal ions via the imine N, O and S atoms. Magnetic and UV-Vis spectra, indicated that the geometrical structure of Mn(II), Co(II) and Ni(II) complexes are an octahedral while Cu(II) is a tetrahedral. The kinetic thermodynamic parameters such as E*, H*, S* and G* were determined for each thermal degradation stage of TG curves of the metal(II) complexes using Coat-Redfern method. Fluorescence studies indicated that the Schiff base ligand HL (ATS), and its metal(II) complexes can serve as potential photoactive materials as indicated from their characteristic fluorescence properties and study the effect of solvent and pH on it. The catalytic activities of metal(II) complexes were studied using H2O2 solution. KEYWORDSONS donor sites Catalytic activity Thermal analysis Schiff base ligand Metals complexes Fluorescence spectra 2-((1-(Thiophen-2-yl)ethylidene)amino)phenol Cite this: Eur.

A novel highly-selective potentiometric sensor based on aquadichloro(E)-2-((1-(thiophen-2-yl)ethylidene)-amino)phenol manganese(II)trihydrate as an anion carrier was developed. The thiocayanate electrode displayed a very high selectivity compared with others inorganic anions. Different sensors with plasticized PVC membranes have been investigated. The sensor's construction contains different amounts of ionophore with and without additives. The pH over 3.56.5 range has been studied. The optimized membrane electrode included 66 mg PVC, 132 mg o-nitrophenyloctylether, 10 mol % tetrakis(trifluoromethyl)phenyl borate, and 2% [Mn(C12H11NOS)(Cl2)(H2O)]. 3H2O. The optimized sensors exhibited Nernstian response for thiocyanate through a linear concentration ranging from (5  10-8 to 9.06  10-3 M) with a detection limit of 3 ×10-8 M and a slope of -57.7 mV/decade, the measurement carried out in acetate buffer pH 4.7. The response time of the electrode was 10 s and the life time of the sensor was more than six weeks. The proposed electrode was effectively utilized for estimation of thiocyanate in saliva samples; the results revealed a valid agreement with reference colorimetric method.