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A new polyoxomolybdate, [(C6H12N4-CH3)2Na2(H2O)8](C6H12N4-CH3)2[(H0.5)N(CH2O)3FeMo6O18.5(OH)2.5]2·10H2O (1), was synthesized. The structure of the synthesized polyoxomolybdate was investigated by single-crystal X-ray diffraction analysis and several other identification techniques such as FTIR and EDX analysis. Each unit cell of 1 contains one cation [(C6H12N4-CH3)2Na2(H2O)8]4+ and two hexamethylenetetramine cations (C6H12N4-CH3)+, and two polyanions [(H0.5)N(CH2O)3FeMo6O18.5(OH)2.5]3– with ten water molecules in the crystal lattice. In the polyanion, molybdenum ions are bonded to two terminal oxygen atoms and two μ2- (Mo-Mo) and μ3- (Mo-Fe-Mo) bridging oxygen atoms. Iron in the center of the polyanion 1 is also surrounded by three deprotonated oxygens of trimethanolamine ligand and three μ3- (Mo-Fe-Mo) bridging oxygen atoms. This new polyoxomolybdate was used as an efficient catalyst in the azide–alkyne cycloaddition reaction to produce various 1,2,3-triazoles with high yields. Additional investigations reveal this catalytic system can be refreshed and utilized for up to six successive applications. [ABSTRACT FROM AUTHOR]

2-Aminoisoindoline-1,3-dione functionalized by Fe3O4@chloro-silane core-shell nanoparticles, then a green and convenient approach for the synthesis of a series of 4H-pyrans by the reaction of aryl aldehydes, malononitrile and methyl acetoacetate in ethanol/60 °C under by using magnetic nanoparticles (MNPs) of Fe3O4@SiO2-NH-isoindoline-1,3-dione is described. The characterization was performed by using a variety of conventional analytical instruments such as Fourier transform infrared spectra, field emission scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometer, thermal analysis. This method provides several advantages such as environmental friendliness, shorter time, excellent yields, easy separation of MNPs with using of external magnet and simple work-up procedure. [ABSTRACT FROM AUTHOR]

A novel oxo-diperoxo tungsten(VI) complex, [WO(O2)2(Hphox)], was prepared by reaction of WO3 in H2O2 with an oxazine-type ligand, 2-(2′-hydroxylphenyl)oxazine (Hphox). The complex was characterized by FTIR, 1H NMR and elemental analysis. The single-crystal X-ray diffraction studies revealed a seven-coordinate tungsten center with a distorted octahedral geometry. The [WO(O2)2(Hphox)] complex was applied as a catalyst in efficient and selective oxidation of sulfide to sulfoxide using 30% H2O2 or UHP (urea hydrogen peroxide) as oxidants. This catalyst showed excellent catalytic activities and high selectivities in producing a variety of aryl and alkyl sulfoxides under mild conditions. To get an insight into the mechanisms of oxidation of sulfides, the mechanistic studies were monitored by UV-Vis spectroscopy. [ABSTRACT FROM AUTHOR]

A new decavanadate polyoxovanadate nanocluster, [2-ampH]6[V10O28]∙2H2O (1), was synthesized through reaction between ammonium vanadate and 2-aminopyridine at pH = 2. Nanocluster 1 was characterized by IR, elemental analysis, and X-ray crystallography. 1 was found to adsorb and desorb dyes and may have widespread application in wastewater treatment. The utility of 1 for adsorption of methylene blue was studied. The adsorbed dyes can be easily desorbed, and 1 has full efficiency after five cycles. [ABSTRACT FROM AUTHOR]

Graphene oxide was an effective supporting material for immobilizing a dioxomolybdenum Schiff base complex via covalent interaction. The large surface of graphene oxide plays important roles to obtain a good degree of catalytic reaction. Catalytic capacity of the graphene-bound dioxomolybdenum Schiff base complex was investigated for the oxidation of various sulfides to sulfoxide compounds using hydrogen peroxide urea as an oxidant. The catalyst was characterized by various techniques including XRD, FTIR, TGA, SEM, UV–vis, and ICP-AES. The immobilized complex was very efficient with the extra benefits of easy recovery and recycling of the heterogeneous catalyst. The graphene oxide bound dioxomolybdenum Schiff base complex was reused for several runs without meaningful loss in catalytic activity. [ABSTRACT FROM PUBLISHER]

A copper-containing polyoxovanadate nanocluster, [(C2H5)4N]4[V8Cu2O24]∙2H2O (1), was synthesized through reaction between the Cu(NO3)2∙3H2O and [(C2H5)4N]4VO3in the molar ratio 1 : 4. Nanocluster1was characterized by IR, elemental analysis, XRD, SEM, TEM, and X-ray crystallography. The catalytic activity of1for the azide–alkyne cycloaddition of different terminal alkynes and organic azides generatedin situfrom sodium azide and different organic halides was tested. The protocol could afford the corresponding products in good to excellent yield at very low catalyst loadings (3.4 Mol%) under the optimized reaction conditions. [ABSTRACT FROM PUBLISHER]

Oxoperoxo tungsten(VI) complex immobilized on Schiff base-modified Fe3O4super paramagnetic nanoparticles were synthesized and appropriately characterized using FT-IR, XRD, SEM, TEM, EDX, BET, and VSM analysis. The synthesized nanoparticles efficiently catalyzed oxidation of benzylic alcohols with H2O2as oxidant in high yields, with high to excellent selectivity. The catalyst can be recovered using an external magnetic field and recycled for subsequent oxidation reactions without any appreciable loss of efficiency. The simple preparation, high activity, excellent selectivity, and simple recoverability of the catalyst are advantageous. [ABSTRACT FROM AUTHOR]

Reaction of the binucleating S-protected ligand precursors 2-(N,N-dimethylthiocarbamato)-5-methylisophthalaldehyde di-2′-hydroxy anil (I) and 2-(N,N-dimethylthiocarbamato)-5-methylisophthalaldehyde di-2′-hydroxy 5′-methyl anil (II) with nickel(II) acetate tetrahydrate in the presence of pyrazole afforded the binuclear nickel(II) complexes [LINi2(pz)] (1) and [LIINi2(pz)] (2), respectively. The complexes have been characterized by routine physicochemical studies as well as by X-ray single crystal structure analysis. In both complexes, Ni(II) ions are doubly bridged by the thiophenolic sulfur of the pentadentate Schiff base ligand and a pyrazolate group. Efficient protocols for the oxidation of sulfides to sulfoxides with high selectivities, catalyzed by binuclear μ-thiophenolato-μ-pyrazolatonickel(II) in the presence of urea hydrogen peroxide (UHP) were explored. We obtained predominantly the monooxygenated product. The resulting products are obtained in good to excellent yields within a reasonable time. [ABSTRACT FROM PUBLISHER]

Mn-doped ZnO nanoparticles, Zn1−xMnxO, were synthesised by a polyethylene glycol (PEG) sol–gel method and the physicochemical properties of compounds were characterised by atomic absorption spectroscopy (AAS), energy-dispersive X-ray analysis, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The catalytic degradation of an organic dye, methylene blue (MB), in the presence of Zn1−xMnxO as the catalyst and hydrogen peroxide (H2O2) as the oxidant at room temperature in water has been studied. Effects of oxidant, catalyst amount, catalyst composition, pH value of the solution and an OH-radical scavenging agent on the degree of the decomposition ofMBdye were also studied. [ABSTRACT FROM AUTHOR]

In this paper, we report that a known dinuclear Fe complex, [tpa(H2O)FeOFe(H2O)tpa](ClO4)4(tpa: tris(2-pyridylmethyl)amine), is an efficient catalyst toward organic sulfide oxidation in the presence of urea-hydrogen peroxide. [ABSTRACT FROM AUTHOR]

The reaction of a solution of MoO2(acac)2in CH3OH and salicylidene 2-picoloyl hydrazone as a tridentate ONO donor Schiff base (ONO) afford a six-coordinated Mo(VI) complex [MoO2(ONO)(CH3OH)], with a distorted octahedral configuration. [MoO2(ONO)(CH3OH)] was isolated as an air-stable crystalline solid and fully characterized by single-crystal X-ray structure analysis. [MoO2(ONO)(CH3OH)] shows reactivity in the oxidation of sulfides to their corresponding sulfoxides using urea hydrogen peroxide as the oxidant at room temperature under air. [ABSTRACT FROM PUBLISHER]

A new mononuclear molybdenum(VI)–oxodiperoxo complex [MoO(O2)2(phox)] with a simple bidentate ligand, 2-(2?-hydroxyphenyl)-5,6-dihydro-1,3-oxazine (Hphox), has been synthesized and characterized by X-ray structure analysis, elemental analysis, infrared, and1H NMR spectroscopy. A triclinic space groupP-1was determined by X-ray crystallography from single-crystal data of this complex. The resulting complex functioned as a facile sulfide oxidation catalyst with urea hydrogen peroxide as terminal oxidant at room temperature. The catalyst showed efficient reactivity in oxidation of sulfides giving high yield and selectivity. [ABSTRACT FROM AUTHOR]

Reactions of a solution of NH4VO3in H2O2and water and salicylidene benzoyl hydrazine as a tridentate Schiff base (ONO) afford a six-coordinate V(V) complex [VO(ONO)(OCH3)(CH3OH)] with a distorted octahedral configuration. The complexes [VO(ONO)(OCH3)(CH3OH)] were isolated as air-stable crystalline solids and fully characterized, including by single-crystal X-ray structure analysis. DFT calculations have been performed to understand the electronic structure of the complex. Vibrational frequencies and maximum absorption wavelengths of the complex theoretically calculated are in good agreement with experimental values. [VO(ONO)(OCH3)(CH3OH)] shows efficient oxidation of sulfides to their corresponding sulfoxides using urea hydrogen peroxide as the oxidant at room temperature under air. [ABSTRACT FROM PUBLISHER]

An oxido-peroxido tungsten(VI) complex [WO(O2)L(CH3OH)] using salicylidene benzoyl hydrazine as a tridentate ONO donor Schiff base (H2L) has been synthesized and characterized by elemental analysis, IR,1H NMR, molar conductance data, and single-crystal X-ray analysis. The complex was used as a catalyst for epoxidation of olefins and oxidation of sulfides. The results show that epoxides and sulfoxides were produced in high yield, turnover number, and selectivity. [ABSTRACT FROM AUTHOR]

A new manganese(III) complex [(N–O)2Mn(OAc)] was synthesized using 2-(2′-hydroxyphenyl)-5,6-dihydro-1,3-oxazine (N–O) as a bidentate O, N donor. The complex has been characterized by elemental analysis, IR, UV–vis spectroscopy, and X-ray structure analysis. Oxidation of sulfides and epoxidation of olefins, respectively, to their corresponding sulfoxides and epoxides were conducted by this catalyst using urea hydrogen peroxide as oxidant at room temperature under air. The catalyst is efficient in oxidation reactions giving high yields and selectivities. [ABSTRACT FROM AUTHOR]

The monoanionic bidentate Schiff base, N-(phenolyl)-benzaldimine (HL), has been employed to synthesize a new vanadium(IV) complex of general composition [VO(L)2] (where L = O, N donor of Schiff base). The ligand and complex have been fully characterized by elemental analyses, molar conductance data, FT-IR, 1H- and 13C-NMR, and UV-Vis spectroscopies. Oxidation of alcohols to their corresponding aldehydes and ketones was conducted by this complex catalyst using Oxone as oxidant under biphasic reaction conditions (CH2Cl2/H2O) and tetra-n-butylammonium bromide as phase transfer agent under air at room temperature. [ABSTRACT FROM AUTHOR]

Zeolitic Imidazole Frameworks (ZIFs) have recently appeared as a new class of nonporous materials featuring notable physicochemical properties. In particular, ZIFs with core-shell structures have drawn a great deal of attention from research communities owing to their unique features, including superior specific surface area, high porosity content, extraordinary thermal, chemical, and structural stability, feasible synthesis conditions in a mild reaction, and facile growth on external surfaces of core nanostructures. This growth facilitates the synthesis of core/shell hybrid materials, which contain both organic (2-MIM) and inorganic (metal nodes) groups. As a structural advantage, the core/shell configuration favorably promotes the potential implementation of ZIFs in various functional fields, e.g. catalysis, drug delivery, adsorption, separation, and purification applications. The current review investigates recent advances in synthesizing and applying ZIFs with core-shell structures. This research review is divided into four parts. The first part overviews synthesis methods for ZIFs and discusses these nanostructures’ structural and material characteristics. The second part summarizes recent achievements and findings on synthesizing different types of ZIFs featuring core-shell structures. In the third part, potential applications of these novel nanostructured materials are presented, and their features are summarized in the final part. [ABSTRACT FROM AUTHOR]