نتایج جستجو برای: solvent free condition

تعداد نتایج: 857817  

The acetylation of various alcohols and phenols was performed successfully using acetic anhydride in the presence of Citric acid coated magnetite nanoparticles as catalyst under solvent-free condition and at 45 °C. The catalyst showed high thermal stability and was recovered and reused at least 5 times without any considerable loss of activity. The present process is environmentally benign and ...

Trimethylsilylation of alcohols and phenols were carried out under solvent-free conditions with hexamethyldisilazane (HMDS) using LaCoO3 perovskite. LaCoO3 as an efficient catalyst accelerated this reaction under milder condition. The advantages of this method are evident regarding, easy separation, low cost and low catalyst loading, lack of pollution, easy work-up, and selective protection of ...

A. Yahyazadeh, V. Azimi

Copper (II) phthalocyanine and 2,9,16,23 tetrakis nitro copper (II) phthalocyaninehas been synthesized respectively from phthalonitrile and 4-nitro phthalonitrile under solvent-free condition using two different catalystsovernanodimensionalzeolites. 4-Nitro phthalonitrile synthesized from phthalimide in three steps. The newly prepared compounds have been characterized by IR, UV-Vis, 1</sup...

Abdul Hossein Abdul Hossein Dabbagh Nader Noroozi Pesyan,

Oxidation of some benzoins to benziles is reported by using p-toluenesulfonic acid as aselective oxidation catalyst under solvent-free condition in high yield. The adjacent carbonylgroup is necessary for the oxidation of hydroxyl group in these compounds. The reaction iscarried out in a sand-bath at 100 °C with minimum by-products.

Journal: :journal of sciences islamic republic of iran 0

in an environmentally benign solventless system, aldehydes and ketones were readily converted to their corresponding azines with hydrazine sulfate, sodium hydroxide and alumina in high yield.

Biginelli-type reaction was developed by means of a three-component condensation of analdehyde, ethyl acetoacetate, urea or thiourea and nano alumina sulfonic acid (Al2O3-SO3H)(NASA) as catalyzed. It is carried out under different conditions. In all conditions, the desiredproducts are obtained in high yields after relatively short reaction times. Nevertheless, thereactions proceeded faster and ...

Abbas Ali Jafari Abdolhamid Bamoniri, BiBi Fatemeh Mirjalili, Fatemeh Abasaltian

Silica supported phosphorus pentoxide (P2O5·SiO2) is an efficient catalyst for synthesis of 1,3,5-substituted pyrazoles via the condensation of 1,3-diketones and hydrazines. Simplicity of procedure, mild condition, being solvent-free, high yields, and easy workup are some advantages of this protocol.

Journal: :iranian journal of catalysis 2015
saeid azimi mohammad ali zolfigol ahmad reza moosavi-zare

friedel–crafts synthesis of triarylmethanes over 3-methyl-1-sulfonicacid imidazolium tetrachloroaluminate under green conditions:in this work, friedel–crafts (fc) alkylation of various arenes with aromatic aldehydes catalyzed by 3-methyl-1-sulfonic acid imidazoliumtetrachloroaluminate {[msim]alcl4}, as a green catalyst, to prepare triarylmethanes (tams) has been carried out. some aromatic aldeh...

Journal: :international journal of nano dimension 0
masoud mohammadi zeydi department of organic chemistry, university of guilan, rasht, iran. nosratollah mahmoodi department of organic chemistry, faculty of sciences, university of guilan, rasht, iran.

an efficient, simple and convenient route is described for the synthesis of biscoumarin (3,3&apos;-(arylmethylene) bis (4-hydroxy-2h-chromen-2-one)) by using of recyclable catalyst tio2@ksf. in this method, we synthesis biscoumarin derivatives via 3multi-component reactions (3mcrs) of two equivalent 4-hydroxycoumarin with one equivalent of aromatic aldehydes using 20 mg nano tio2@ksf as homogen...

Journal: :iranian chemical communication 2015
bagher mohammadi mansoor shafieey hamed kazemi

this work described an efficient pseudo four-component synthesis of (10e)-n-benzylidene-2-phenylh-imidazo[1,2-a]pyridin-3-amine derivatives from 2-aminopyridin, malononitrile and arylaldehydes in the presence of naoh under solvent-free and conventional heating condition in good to excellent yields. a wide range of aromatic aldehydes would easily undergo condensations with 2-aminopyridin and mal...

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