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1.
Synthesis,Electrochemical and Luminescence Studies of Nickel and Vanadium Complexes Containing Tetradentate Schiff Base Ligand with N2O2 Donor Atoms 下载免费PDF全文
A symmetrical tetradentate Schiff base ligand was derived by the condensation of ortho‐vanillin and thiourea in 2:1 molar ratio and adjusted pH. Nickel and vanadyl complexes were obtained using the template method by the reaction of ortho‐vanillin and thiourea with Ni(OAc)2. 4H2O and VO(acac)2 (2:1:1 molar ratio) in absolute ethanol and adjusted pH. The Schiff base ligand and its complexes have been characterized by FT‐IR, 1H NMR, UV/Vis, elemental analysis and conductometry measurements. In nickel and also vanadyl complexes the ligands were coordinated to the metals via the imine N and enolic O atoms. The complexes have been found to possess 1:1 metal to ligand stoichiometry and the molar conductance data revealed that the metal complexes were non‐electrolytes. The nickel and vanadyl complexes exhibited tetrahedral and square pyramidal coordination geometry, respectively. The emission spectra of the ligand and its complexes were studied in DMSO. Electrochemical properties of the ligand and its complexes were also investigated in the DMF solvent at the 150 mVs‐1 scan rate. The ligand and its complexes showed irreversible processes at this scan rate. 相似文献
2.
Khodabakhsh Niknam Dariush Saberi Mojtaba Baghernejad 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):875-882
Silica bonded S-sulfonic acid (SBSSA) was prepared by the reaction of 3-mercaptopropylsilica (MPS) and chlorosulfonic acid in chloroform. Silica-bonded S-sulfonic acid, as a reusable solid acid catalyst, was used for the condensation reactions of indole with carbonyl compounds at ambient temperature. Tetra-(indolyl)methanes were also obtained by the condensation reaction of indole with dialdehyde compounds. Silica bonded S-sulfonic acid was recovered and reused. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
3.
A three-component domino reaction between a 3-formylchromone, an isocyanide, and 1,3-dimethylalloxan which affords novel 5-(furo[3,4-b]chromenyl)-5-hydroxybarbiturate derivatives is reported. The reaction sequence consists of an initial [4+1] cycloaddition followed by an activated electrophilic heteroaromatic substitution on the furan ring to afford the products. This novel cascade reaction sequence represents an atom-economic route to biologically interesting molecules. 相似文献
4.
Substituent effect on the structure and electronic properties of H2Si=SiHAr (Ar = p-C6H4X; X = NH2, OH, Me, H, F, Cl, CHO, COOH, CN, NO2) molecules are studied at the CAM-B3LYP/6-311G(d,p) level of theory. Energy decomposition analysis (EDA) is used as a useful tool for illustrating the interaction between H2Si and SiHAr fragments in HArSi=SiH2 molecules. Energetic analysis reveals that the singlet state of the fragments is more stable than triplet state. Also, interactions are stronger in the presence of electron-withdrawing groups (EWGs) in comparison to electron donating groups (EDGs). EDG and EDG effects are investigated on the stability of fragments, frontier orbital energy, distortion, HOMO–LUMO gap, electron-donating (ω−) and electron-accepting (ω+) powers of the studied molecules. Then, the correlations between these calculated parameters with the Hammett and Brown constants (σp and σp+, respectively) are provided. Also, time-dependent density functional theory method (TD-DFT) is employed for the determination of the strongest absorption band values (λmax,el) of these molecules. This absorption band is attributed to the HOMO →LUMO transition. 相似文献
5.
Majid M. Heravi Hamideh Alinejhad Fatemeh Derikvand Hossein A. Oskooie Bita Baghernejad Fatemeh F. Bamoharram 《合成通讯》2013,43(14):2033-2039
We report here two simple methods for the synthesis of benzo[c]acridine derivatives from three-component, one-pot condensation of 1-naphthylamine, dimedone, and a variety of substituted aldehydes in the presence of a catalytic amount of NH2SO3H or H6P2W18O62 · 18H2O under solvent-free conditions at 120 °C or in refluxing ethanol. 相似文献
6.
Tamoradi Taiebeh Mehraban-Esfandiari Bita Ghadermazi Mohammad Ghorbani-Choghamarani Arash 《Research on Chemical Intermediates》2018,44(2):1363-1380
Research on Chemical Intermediates - In the present research, a magnetically recoverable catalyst was easily prepared by anchoring nickel onto the surface of organically modified magnetite... 相似文献
7.
3,4,6‐Trisubstituted 2‐pyridone derivatives have been synthesized in good to excellent yields through a condensation reaction of various 1,3‐diketones with amides in the presence of 1,4‐Diaza‐bicyclo[2,2,2]octane (DABCO) at reflux temperature. 相似文献
8.
Alcohols and phenols were efficiently acylated with acetic anhydride in the presence of vanadyl sulfate (VOSO4.3H2O) at room temperature in high yields. 相似文献
9.
Shrinkage microporosity in cast aluminum was characterized utilizing the frequency dependence of ultrasonic attenuation caused by scattering from the pores. Measurements were made with the plate specimen immersed in water, and, by using a focused transducer, spatial resolution of about 2 mm was obtained. An accurate measure of attenuation was obtained by comparing the specimen’s ultrasonic signal with that from a pore-free reference specimen. Although the attenuation could be fitted using a single spherical pore size, better fits were obtained by assuming a lognormal distribution of spheres. Pore volume fraction inferred from the lognormal fits overestimates the actual volume fraction, determined from density measurements, by the same factor for all volume fractions. The actual volume fraction is overestimated by more than 100%, due to the complicated, nonspherical pore shapes, and must be taken into account to obtain accurate values of porosity. The strong correlation (r2=0.97) between ultrasonic and density-derived volume fractions permits reliable, nondestructive laboratory measurements of porosity. 相似文献
10.
Marjaneh Jafari Fesharaki Gholamreza Nabiyouni Bita Shahdoost Seyed Farshad Akhtarianfar 《Journal of Cluster Science》2016,27(3):1005-1015
NiFe2?x Bi x O4 (x = 0, 0.1, 0.2, 0.3) nanoparticles with various grain sizes were synthesized via annealing treatment followed by ball milling of its bulk component materials. Commercially available bismuth, nickel and iron oxide powders were first mixed and then annealed at 1200 °C in an oxygen environment furnace for 4 h. The samples were then milled for 2 h by high-energy ball milling. X-ray diffraction (XRD) pattern indicated that in this stage the samples are single phase. The microstructure investigation was carried out by a scanning electron microscope with maximum magnification of 30,000. The average grain size for different samples was estimated by XRD technique and transmission electron microscopy. Magnetic behavior of the samples at room temperature was studied using an alternating gradient force magnetometry. The Néel temperature of the powders was measured by a Faraday balance. Based on magnetic studies, increase in bismuth content leads to a decrease in the saturation magnetization, coercive field and Néel temperature. This can be attributed to the substitution of Bi3+ ion in the ferrite system as a nonmagnetic cation. 相似文献