Polyoxomolybdate [Mo_(36)O_(110)(NO)_4(H_2 O)_(14)]·52 H_2 O was synthesized by a simple one-pot procedure through reducing an acidified mixture of Na_2 MoO_4·2 H_2 O and NH_2 OH·HCl. In order to create...Polyoxomolybdate [Mo_(36)O_(110)(NO)_4(H_2 O)_(14)]·52 H_2 O was synthesized by a simple one-pot procedure through reducing an acidified mixture of Na_2 MoO_4·2 H_2 O and NH_2 OH·HCl. In order to create a heterogeneous catalyst system, the polyoxomolybdate was pillared with MgAl-LDH-NO_3 by direct ion exchange. These novel materials were carefully analyzed by various chemico-physical methods. The catalytic degradation of methylene blue(MB) and rhodamine B(RB) as common dyes in the presence of MgAl-LDH-1 nanoparticles with aqueous hydrogen peroxide, H_2 O_2, as an oxidizing agent was studied in aqueous solution at room temperature. More importantly, the catalyst can be recovered and reused efficiently up to five consecutive cycles with negligible loss of catalytic activity.展开更多
Octavinyl polyhedral oligomeric silsesquioxane (POSS) was polymerized on the surface of Fe3O4 nanoparticles (NPs) and then the NPs were functionalized with carboxylic acid groups using thiol-ene click reactions with t...Octavinyl polyhedral oligomeric silsesquioxane (POSS) was polymerized on the surface of Fe3O4 nanoparticles (NPs) and then the NPs were functionalized with carboxylic acid groups using thiol-ene click reactions with thioglycolic acid.The as-prepared Fe3O4@POSS-COOH magnetic hybrid NPs had mesoporous structures with an average particle diameter of 15 nm and a relatively high specific surface area of 447 m^2· g^-1.Experimental results showed that 4 mg of Fe3O4@POSS-COOH NPs efficiently adsorbed and removed methylene blue from water at 5 min.This is due to the presence of both carboxylic acid and pendant vinyl groups on the Fe3O4@POSS-COOH NPs.These NPs could be easily withdrawn from water within a few seconds under moderate magnetic field and showed high stability in acid and alkaline aqueous mediums.展开更多
The system,Pd（OAc）_2/imidazolium salts（L_2）,was found as an efficient catalyst in the Heck coupling reaction of olefins with aryl halides and Suzuki reactions of various aryl halides with aryl boronic acids under ...The system,Pd（OAc）_2/imidazolium salts（L_2）,was found as an efficient catalyst in the Heck coupling reaction of olefins with aryl halides and Suzuki reactions of various aryl halides with aryl boronic acids under aerobic condition.This catalytic system demonstrates great tolerance to a wide range of groups on all substrates of aryl halides,alkenes and aryl boronic acids.展开更多
The phosphazane derivatives （L1-3） were readily obtained by reaction of different ratios of PCI3 and PhNH2. The L1_3 derivatives were found to be efficient ligands in the palladium-catalyzed Suzuki C-C coupling reac...The phosphazane derivatives （L1-3） were readily obtained by reaction of different ratios of PCI3 and PhNH2. The L1_3 derivatives were found to be efficient ligands in the palladium-catalyzed Suzuki C-C coupling reactions in water. It was determined that with the use of L1-3/Pd（OAc）2 system as a catalyst, aryl halides undergo Suzuki cross-couplings with arylboronic acids to give the desired products in moderate to excellent yields.展开更多
Cu2O nanocubes,octahedra,spheres and truncated rhombic dodecahedral were prepared and their structural,morphological,and electronic properties were investigated by X-ray diffraction analysis.X-ray absorption near edge...Cu2O nanocubes,octahedra,spheres and truncated rhombic dodecahedral were prepared and their structural,morphological,and electronic properties were investigated by X-ray diffraction analysis.X-ray absorption near edge structure,scanning electron microscope and transmission electron microscope and X-ray absorption near edge structure.Cu2O nanocrystals were successfully employed to catalyze the 1,3-dipolar cycloaddition reaction for the synthesis of 1,4-disubstituted triazoles.Cu2O nanocubes and octahedral showed the superior catalytic performance in the cycloaddition reaction.These results reveal that crystal-plane engineering of oxide catalysts is a useful strategy for developing efficient catalysts for organic reaction.展开更多
基金Supported by the Iranian National Science Foundation(INSF)and University of Maragheh
文摘Polyoxomolybdate [Mo_(36)O_(110)(NO)_4(H_2 O)_(14)]·52 H_2 O was synthesized by a simple one-pot procedure through reducing an acidified mixture of Na_2 MoO_4·2 H_2 O and NH_2 OH·HCl. In order to create a heterogeneous catalyst system, the polyoxomolybdate was pillared with MgAl-LDH-NO_3 by direct ion exchange. These novel materials were carefully analyzed by various chemico-physical methods. The catalytic degradation of methylene blue(MB) and rhodamine B(RB) as common dyes in the presence of MgAl-LDH-1 nanoparticles with aqueous hydrogen peroxide, H_2 O_2, as an oxidizing agent was studied in aqueous solution at room temperature. More importantly, the catalyst can be recovered and reused efficiently up to five consecutive cycles with negligible loss of catalytic activity.
文摘Octavinyl polyhedral oligomeric silsesquioxane (POSS) was polymerized on the surface of Fe3O4 nanoparticles (NPs) and then the NPs were functionalized with carboxylic acid groups using thiol-ene click reactions with thioglycolic acid.The as-prepared Fe3O4@POSS-COOH magnetic hybrid NPs had mesoporous structures with an average particle diameter of 15 nm and a relatively high specific surface area of 447 m^2· g^-1.Experimental results showed that 4 mg of Fe3O4@POSS-COOH NPs efficiently adsorbed and removed methylene blue from water at 5 min.This is due to the presence of both carboxylic acid and pendant vinyl groups on the Fe3O4@POSS-COOH NPs.These NPs could be easily withdrawn from water within a few seconds under moderate magnetic field and showed high stability in acid and alkaline aqueous mediums.
基金the Research Council of University of Maragheh for financially support of this workM.B.thanks the Sharif University of Technology for funding of this work
文摘The system,Pd（OAc）_2/imidazolium salts（L_2）,was found as an efficient catalyst in the Heck coupling reaction of olefins with aryl halides and Suzuki reactions of various aryl halides with aryl boronic acids under aerobic condition.This catalytic system demonstrates great tolerance to a wide range of groups on all substrates of aryl halides,alkenes and aryl boronic acids.
基金the Research Council of University of Maragheh and Shahid Chamran University for funding of this work
文摘The phosphazane derivatives （L1-3） were readily obtained by reaction of different ratios of PCI3 and PhNH2. The L1_3 derivatives were found to be efficient ligands in the palladium-catalyzed Suzuki C-C coupling reactions in water. It was determined that with the use of L1-3/Pd（OAc）2 system as a catalyst, aryl halides undergo Suzuki cross-couplings with arylboronic acids to give the desired products in moderate to excellent yields.
基金the Iranian National Science Foundation(INSF)Sharif University of Technology and University of Maragheh for financial supports of this work
文摘Cu2O nanocubes,octahedra,spheres and truncated rhombic dodecahedral were prepared and their structural,morphological,and electronic properties were investigated by X-ray diffraction analysis.X-ray absorption near edge structure,scanning electron microscope and transmission electron microscope and X-ray absorption near edge structure.Cu2O nanocrystals were successfully employed to catalyze the 1,3-dipolar cycloaddition reaction for the synthesis of 1,4-disubstituted triazoles.Cu2O nanocubes and octahedral showed the superior catalytic performance in the cycloaddition reaction.These results reveal that crystal-plane engineering of oxide catalysts is a useful strategy for developing efficient catalysts for organic reaction.
