نتایج جستجو برای: nanomagnetic heterogeneous catalyst
تعداد نتایج: 166813 فیلتر نتایج به سال:
In this study, Mn (III) salen complex was synthesized and immobilized onto the graphene oxide, which is modified by 3-chloropropyltrimethoxy silane. Heterogeneous catalyst was characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, fourier transform infrared spectra, nitrogen adsorption−desorption isotherm and atomic absorption spectroscopy. The catalyt...
cobalt hydrogensulfate is an efficient catalyst for the condensation of β-naphthol, aromatic aldehydes and 5,5-dimethyl-1,3-cyclohexanedione at 120 °c to afford 9,9-dimethyl-12-phenyl-8,10,11,12-tetrahydro-9-h-benzo[a]xanthen-11-one derivatives in high yields. also, polycondensation reactions of phenols with phthalic anhydride were carried out in the presence of cobalt hydrogensulphate under so...
silica sulfuric acid as an efficient and reusable heterogeneous catalyst has been used for the preparation of amidines 2 from formimidate 1 by reaction with aromatic amines at room temperature in good to excellent yields. imidate was prepared by treatment of equimolar quantities of triethyl orthoformate and diaminomaleonitrile in refluxing dioxane. all the compounds were characterized fully by ...
the aryl-(z)-n-[2-amino-1,2-dicyanovinyl]formamidine 2 cyclize in solvent-free conditions and in the presence of a base to give a 5-amino-1-aryl-4-cyanoimidazoles 3. silica sulfuric acid as an efficient and reusable heterogeneous catalyst has been used for the preparation of amidines 2 from formimidate 1 through reaction with aromatic amines at room temperature and in good to excellent yields. ...
simple, cheap and green protocol for effective conversion of alcohols to corresponding carbonyl compounds in the presence of h14[nap5w30o110] and ammonium nitrate is reported. the products were characterized by ft-ir and comparison of their physical properties with those reported in the literatures. the progress of the reaction was monitored by thin layer chromatography (tlc) technique. the ali...
An efficient and eco-friendly method for the one-pot synthesis of 14-aryl-14H-dibenzo [a,i]xanthene-8,13-dione derivatives has been developed in the presence of Fe3O4@SiO2 core-shell nanoparticles. The multi-component reactions of 2-hydroxy-1,4-naphthoquinone, β-naphthol and aldehydes were efficiently catalyzed using novel nano-scale materials under reflux conditions. The present method offers ...
SnCl4/nano-sawdust was prepared as a carbohydrate-based catalyst containing of tin bearing cellulose units. The catalyst was characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDS). The catalyst was applied successfully as a readily available, inexpensive, biodeg...
a green, efficient and selective approach for the oxidation of sulfides to sulfoxides and sulfones with uhp at room temperature is reported. the reaction is performed in the presence of vanadia catalyst supported on mesocellular silica foam (mcf) with a v content ranging from 2% to 10% as heterogeneous and reusable catalyst. the structural and textural characterization of this catalyst were don...
this work described one pot syntheses of polysubstituted 2,6- dicyanoaniline and 2-(3-oxo-1,3-diarylpropyl) malononitrile derivatives in the presence of mgo nanoparticles (nps) under grinding conditions and microwave irradiation, respectively. the simple experimental procedure includes shorter reaction times, higher yields, lower cost and environmental friendliness. other remarkable features ar...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید