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Very Effective Catalyst (very + effective_catalyst)
Selected AbstractsAn Environmentally Benign, Highly Efficient Catalytic Reduction of p -Nitrophenol using a Nano-Sized Nickel Catalyst Supported on Silica-AluminaADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7 2010Islam Hamdy Abd El Maksod Abstract A green and effective method is reported for the reduction of p -nitrophenol to p -aminophenol using a nano-sized nickel catalyst supported on silica-alumina in the presence of hydrazine hydrate as an alternative source of hydrogen. It was found that nickel loaded on a silica-alumina support is a very effective catalyst in the hydrogenation of p -nitrophenol to p -aminophenol. Thus it attained 100% conversion in only 69 seconds instead of 260 seconds for commercial Raney nickel. In addition, the possibility to reuse it more than one time with great efficiency gives it another advantage over commercial Rainey nickel which cannot be used more than once. This economical and environmentally friendly method provides a potentially new approach for the synthesis of the intermediate product of paracetamol in industry, which overcomes the drawbacks of the known reduction methods. The prepared catalysts were fully characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and electron spin resonance (ESR) tehniques. [source] Hydrogen-Bonding Catalysis: Mild and Highly Chemoselective Oxidation of SulfidesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2009Alessio Russo Abstract N,N, -Bis[3,5-bis(trifluoromethyl)phenyl]thiourea, employed at only 1,mol% loading, was found to be a very effective catalyst for the oxidation of sulfides with tert -butyl hydroperoxide (TBHP), affording the sulfoxides in high yield, excellent chemoselectivity, fairly good diastereoselectivity. [source] Creation of a Monomeric Ruthenium Species on the Surface of Micro-Size Copper Hydrogen Phosphate: An Active Heterogeneous Catalyst for Selective Aerobic Oxidation of AlcoholsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 16 2007Junhua Liu Abstract A new micro-size copper hydrogen phosphate (CHP) synthesized by the emulsion method combined with a monomeric ruthenium species was found to be a very effective catalyst for the selective oxidation of alcohols. Several kinds of alcohols were transformed into the corresponding aldehydes or ketones over the RuCHP catalyst by oxygen under very mild conditions. The results showed that the CHP material was perfect as a catalyst support due to its high ion-exchange ability and adsorption capacity. [source] Iron-catalyzed efficient three-component allylation of imine in aqueous mediaAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 12 2009Yu Yuan Abstract Iron trichloride hexahydrate has proved to be a very effective catalyst for the three-component condensation of aromatic aldehydes, amines and allyltributylstannane, which produces high yields of homoallylic amines in water in the presence of surfactant SDS. Copyright © 2009 John Wiley & Sons, Ltd. [source] Homo-coupling of Aryl Iodide and Bromide Catalyzed by Immobilized Palladium with a Bidentate Nitrogen LigandCHINESE JOURNAL OF CHEMISTRY, Issue 10 2009Xiaofang Chen Abstract The immobilized palladium onto organic-inorganic hybrid material, which contains bidentate nitrogen ligands, was a very effective catalyst for homo-coupling of aryl iodide and bromide. The protocol involved the use of N,N -dimethylacetamide as a solvent, and n -tributylamine as a base. The reaction generated the corresponding homo-coupling products in good to excellent yields at low catalyst loading (0.20 mol%). Furthermore, the silica-supported palladium catalyst could be recovered and recycled by a simple filtration of the reaction solution and used for five consecutive trials without loss of its activity. [source] | ||||||||||