For carbon steel X70 in a 1 M hydrochloric acid solution, Scorzonera undulata acetate extract (SUAc) was investigated as an ecological corrosion inhibitor. The anti-corrosion effect of Scorzonera undulata extract is studied using potentiodynamic polarization analysis and electrochemical impedance spectroscopy (EIS). The polarization curves clearly show that the extract is an excellent mixed inhibitor.
View Article and Find Full Text PDFThe reaction between the 2-(1-(2,6-di(pyrazol-1-yl)-4-methylpyridyl)-4,5-(4,5-bis(propylthio)-tetrathiafulvalenyl)-1-benzimidazol-2-yl)-pyridine ligand (L), 1 equivalent of Ln(hfac)·2HO/Dy(tta)·2HO (hfac = 1,1,1,5,5,5-hexafluoroacetylacetonate, tta = 2-thenoyltrifluoroacetonate) and M(hfac)·2HO leads to the formation of heteroleptic 3d-4f dinuclear complexes of formula [MLn(hfac)(L)] (M(II) = Cd, Zn, Co, Mn, Ni and Ln(III) = Dy, Yb, Nd) and [ZnDy(tta)(hfac)(L)]·(CHCl). Their X-ray structures reveal that the two coordination sites are occupied by one Ln(III) ion and one M(II) transition metal respectively. The M(II) ions are coordinated to the benzoimidazolylpyridine (bzip) moiety in a NO coordination sphere, while the Ln(III) ions are coordinated to the 2,6-di(pyrazol-1-yl)-4-pyridine (dpp) moiety in a NO surrounding.
View Article and Find Full Text PDFForming complexes with cyclodextrins can protect nicotinic acid (vitamin B3) from premature metabolism and enhance the solubility and stability of this drug. In this work, the formation of the inclusion complex of the neutral form of nicotinic acid and β-cyclodextrin was achieved. The complex is modeled using PM3, PM6-D4H3, and PM7, by considering two orientations of the guest: A and B, one is from wide to narrow rim, and the second is from narrow to the wide rim, respectively.
View Article and Find Full Text PDFThe synthesis of new unsymmetrically benzene-fused bis (tetrathiafulvalene) has been carried out by a cross-coupling reaction of the respective 4,5-dialkyl-1,3-dithiole-2-selenone 6-9 with 2-(4-(p-nitrophenyl)-1,3-dithiole-2-ylidene)-1,3,5,7-tetrathia-s-indacene-6-one 5 prepared by olefination of 4-(p-nitrophenyl)-1,3-dithiole-2-selenone 3 and 1,3,5,7-tetrathia-s-indacene-2,6-dione 4. The conversion of the nitro moiety 10a-d to amino 11a-d then dibenzylamine 12a-d groups respectively used reduction and alkylation methods. The electron donor ability of these new compounds has been measured by cyclic voltammetry (CV) technique.
View Article and Find Full Text PDFThe synthesis and properties of a series of bis-tetrathiafulvalenes (bis-TTFs) containing nitrophenyl, aminophenyl or dimethylaminophenyl is reported. The synthesis was carried out by using routes involving Wittig-type, cross-coupling, reduction and alkylation reactions. The electron donor ability of these new compounds has been measured by cyclic voltammetry (CV).
View Article and Find Full Text PDFWe report the synthesis and properties of eight new tetrathiafulvalene (TTF) derivatives containing two different functionalities, prepared with the aim of obtaining stable organic materials. The four acetoxyphenyl- and four hydroxyphenyl TTFs were synthesized via Wittig-type condensations. The electrochemical properties of these redox-active molecules were studied by cyclic voltammetry.
View Article and Find Full Text PDFA new trimethyltetrathiafulvalene (Me3TTF) derivative Me3TTF-CH=CH-py bearing a pyridyl was synthesized and coordinated to a cobalt(II) benzoate dimer, having paddlewheel core structure, leading to a complex formulated as Co2(PhCOO)4(Me3TTF-CH=CH-py)2. Single-crystal X-ray diffraction studies of the complex performed at 293 and 100 K evidenced the existence of a weak metal-metal interaction. Magnetic studies revealed an antiferromagnetic behavior, which is explained as the result of the direct exchange between metal centers.
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