نتایج جستجو برای: heterogeneous and reusable catalyst

تعداد نتایج: 16853269  

Journal: :Chemical communications 2008
Anna Komáromi Zoltán Novák

Palladium on charcoal serves as an efficient and reusable solid supported catalyst for the Sonogashira coupling of aryl chlorides with terminal acetylenes in the presence of a bulky, electron-rich biphenyl type ligand (XPhos), without copper co-catalyst.

Ali Ramazani, Fariba Sadri, Hamideh Ahankar, Mehdi Khoobi, Nahid Dayyani, Pegah Azimzadeh Asiabi Saeid Taghavi Fardood Sang Woo Joo

Nanomagnetic MgFe2O4 is an active, stable, and reusable catalyst for the oxidation of alcohols. The oxidation of various primary and secondary alcohols has been examined and related corresponding products were obtained in good yields. The reactions were carried out in the presence of water as solvent and oxone (at room temperature) or H2O2 (at 60 ºC) as an oxidant. The catalyst was investigated...

An  efficient  three-component  one-pot  synthesis  of 1-amidoalkyl-2-naphthols  from  2-naphthol, aldehydes, and acetamide using nano-SnO2as catalyst is described. The reactions were carried out at 80oC under water-solvent media. The structures of the compounds were characterized by IR, 1HNMR, 13C-NMR,  and  Mass  spectra  and  by  elemental  analysis.  The  advantages  of  the  effective meth...

Journal: :journal of the iranian chemical research 0
hossein behmadi department of chemistry, faculty of basic sciences, islamic azad university , mashhad branch, mashhad 91735-413, iran seyed mahdi saadati young researchers club, islamic azad university, mashhad branch, mashhad, iran mina roshani department of chemistry, faculty of basic sciences, islamic azad university , mashhad branch, mashhad 91735-413, iran hasan mohammadi department of chemistry, faculty of basic sciences, islamic azad university , mashhad branch, mashhad 91735-413, iran abbas razavi department of chemistry, faculty of basic sciences, islamic azad university , mashhad branch, mashhad 91735-413, iran marjan ramezani department of chemistry, faculty of basic sciences, islamic azad university , mashhad branch, mashhad 91735-413, iran

a new, convenient, efficient, and cost-effective one-pot synthesis of 1hphenanthro[9,10]imidazol-2-yl from phenanthraquinone and aldehydes, using sulfuric acidimmobilized on silica as catalyst is described. the present methodology offers severaladvantages such as excellent yields, simple procedure, shorter reaction times, the use ofinexpensive reagents, easy recovery and eco-friendly. in additi...

Journal: :nanochemistry research 1999
eshagh rezaee nezhad ezatallah pourmalekshahi

an efficient and simple method for the preparation of si-imidazole-hso4 functionalized magnetic fe3o4 nanoparticles (si-im-hso4 mnps) and used as an efficient and reusable magnetic catalysts for the regioselective ring opening of epoxides under green conditions in water. this catalyst was used for the ring opening of epoxide corresponding to the thiocyanohydrins and azidohydrines. compared to t...

Abdolhossain Massoudi Ali Ramazani Fariba Sadri Leila Dolatyari Mehdi Khoobi Sang Woo Joo Vahid Azizkhani

Nanomagnetic NiFe2O4 was used as the efficient, stable, reusable catalyst for selective oxidation of alcohols to their corresponding carbonyl compounds using oxone (potassium hydrogen monopersulfate) as oxidant in the presence of water as solvent at room temperature. The oxidation of various primary and secondary alcohols has been examined and related corresponding products were obtained wi...

Journal: :iranian journal of catalysis 2014
javad safari zohre zarnegar simin naseh zahra akbari

a simple highly versatile and efficient sonochemical synthesis of 1,2,4,5-tetrasubstituted and 2,4,5-trisubstituted imidazoles is achieved by condensation of 1,2-dicarbonyl compound, aldehyde, ammonium acetate and primary amine using antimony trichloride immobilized on silica gel (sio2-osbcl2) as a catalyst in ethanol at moderate temperature. operational simplicity, practicability and applicabi...

2001
G. Romanelli H. Thomas

Deprotection of various phenols from their respective methoxymethyl ethers using an heteropolyacid catalyst was studied. The catalyst was the Wells-Dawson heteropolyacid, used both in bulk or supported on silica. Yields were high to quantitative after less than one hour reaction time and the catalyst was easily recoverable and reusable.

Journal: :iranian journal of catalysis 2012
ahmad reza massah roozbeh javad kalbasi mitra toghyani

sulfonated polystyrene/montmorillonite nanocomposite (ommt/ps-so3h) was prepared and used as a novel, efficient and inexpensive heterogeneous acid catalyst in the one-pot reaction three-component mannich reaction of ketones, aromatic aldehydes and amines under solvent-free conditions. the catalyst was characterized by xrd, sem, tg, bet and ft-ir techniques. this method has advantages of high yi...

Abdol Hajipour Fatemeh Rafiee

A simple and mild method for tetrahydropyranylation of alcohols is reported at room temperature using a catalytic amount of 3-methylimidazolinium hydrogensulfate([Hmim]HSO4) as a green, efficient and reusable catalyst. Using solvent-free conditions, non-toxic and inexpensive materials, modest and clean work-up, short reaction times and high yields of the products are the advantages o...

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