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121.
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Sulfonic acid groups were grafted onto three different types of synthesized magnetic nanoparticles, namely Fe3O4, Fe3O4@SiO2, and Fe3O4@MCM‐48. The sulfonic acid‐functionalized nanoparticles were evalu...  相似文献   
123.
Molecular Diversity - In an attempt to obtain the modified and novel insecticides with low human toxicity, a series of novel mono-, bis-, and tetraphosphonic acid derivatives were designed and...  相似文献   
124.
Two carboxamide ligands, H2bqbenzo {3,4-bis(2-quinolinecarboxamido)benzophenone} and H2bqb {N,N′-bis[(2-quinolinecarboxamide)-1,2-benzene]}, have been prepared using tetrabutylammonium bromide as an environmentally benign reaction medium. Two new Pd(II) complexes, [PdII(bqbenzo)] (1) and [PdII(bqb)] (2), have been synthesized, characterized, and their structures determined by single crystal X-ray diffraction. The di-anionic ligands, bqbenzo2? and bqb2?, are coordinated via two Namide atoms and the nitrogens of the two quinoline rings, with Pd?Namide < Pd–Nquinoline bond lengths. The geometry around palladium(II) in both complexes is distorted square planar. The electrochemical behaviors of the ligands and their Pd(II) complexes have been investigated by cyclic voltammetry in DMF. An irreversible PdII/I reduction is observed at ?1.06 V for 1 and at ?1.177 V for 2, indicating the influence of the R substituent on the central phenyl ring of carboxamide ligands on the PdII/I reduction potential. The ligands and palladium complexes were also screened for in vitro antibacterial activity. The Pd(II) complexes show strong biological activity against S.typhi and E.coli as Gram ?ve and B.cereus and S.aureus as Gram +ve bacteria comparable to the antibiotic penicillin. The antibacterial results also reveal that coordination of Pd(II) significantly improves the activity.  相似文献   
125.
In this paper, we present an efficient and practical method for oxidation of alcohols to their corresponding carbonyl compounds catalyzed by [Mn(salophen)@nSTD]. This catalyst was synthesized, and characterized by FT-IR, UV–Vis, TGA, SEM and TEM. The results of experiments proved that this catalyst has excellent selectivity and high activity in the oxidation of different primary and secondary alcohols to their corresponding aldehyde and ketone at room temperature. The effects of important factors in the oxidation of alcohols such as kind of oxidant, solvent and amount of catalyst were investigated in the oxidation of 4-chlorobenzyl alcohol. This catalyst shows high stability and reusability after six catalytic runs.  相似文献   
126.
Asymmetric bidentate Schiff base ligand (HL) and its cobalt(III), nickel(II), and copper(II) complexes have been synthesized (where L = 2-[(4-methoxy-2-nitrophenyl)iminomethyl]phenol). The ligand and its metal complexes have been characterized by elemental analyses (CHN) and FTIR spectroscopy. Thermogravimetric analyses of the compounds reveal their thermal stabilities along with their thermal decomposition pattern. In addition, the complexes have been used for the preparation of corresponding metal oxide nanoparticles by controlled aerobic thermal decomposed at 500 °C. The FTIR pattern of the obtained solids receals the formation of the metal oxides nanoparticles.  相似文献   
127.
An efficient and green method for the synthesis of phthalide [isobenzofuran-1(3H)-one] fused pyrazoles via the catalyst-free condensation reaction of 2-formylbenzoic acid, hydrazine hydrate, and acetylenic esters in water is reported. Reaction of 2-formylbenzoic acid with 6-amino-uracils or cyclic 1,3-diketones resulted in the formation of phthalide-fused pyrimidine or cyclic 1,3-diketone derivatives.  相似文献   
128.
Molecular Diversity - A series of ethyl 2-amino-4H-benzo[h]chromene-3-carboxylate derivatives, having phenyl ring with diverse substituents at C4 position of 4H-benzochromene nucleus, were...  相似文献   
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A one-step green-chemistry method was applied to prepare sulfur/reduced graphene oxide (S/RGO). The synthesized S/RGO was modified by 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (TCPP) and Fe3O4 nanoparticles to form TCPP–Fe3O4@S/RGO. The prepared composites were investigated by X-ray diffraction (XRD) analysis, Fourier-transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray (EDX) mapping, and transmission electron microscopy (TEM) and scanning electron microscopy (SEM) imaging. Diffuse reflectance spectroscopy (DRS) was used to determine the photocatalytic ability of S/RGO and TCPP–Fe3O4@S/RGO. In addition, photocatalytic degradation of a hazardous dye (methylene blue) by the TCPP–Fe3O4@S/RGO composite under visible-light irradiation is reported. The results demonstrate synthesis of TCPP–Fe3O4@S/RGO by an environmentally friendly method with excellent degradation effect.  相似文献   
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