نتایج جستجو برای: catalyst-free

تعداد نتایج: 553796  

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه رازی - دانشکده علوم 1392

a novel acrylic acid-functionalized fe3o4 magnetic nanoparticle with a core-shell structure was developed for utilization as a heterogeneous organosuperacid in chemical transformations. the structural, surface, and magnetic characteristics of the nanosized catalyst were investigated by various techniques such as transmission electron microscopy (tem), thermogravimetric analysis (tga), and ft-ir...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه شیراز - دانشکده علوم 1391

in this thesis, we exploit a simple and suitable method for immobilization of copper(ii) complex of 4?-phenyl-terpyridine on activated multi-walled carbon nanotubes [amwcnts-o-cu(ii)-phtpy]. this nanostructure was characterized by various physico-chemical techniques. to ensure the efficiency and fidelity of copper species, the implementation of three-component strategies in click-chemistry all...

Journal: :physical chemistry and electrochemistry 0

2-amino-substituted ketones react with α-methylene ketones under solvent-free conditions at 90 °c in thepresence of a catalytic amount of zirconium dodecylphosphonate to create the corresponding quinolinesin excellent yields. this procedure recommends numerous advantages such as easy work-up, use of mild,reusable and safe catalyst, short reaction timeand high yields. the new compounds have been...

Journal: :international journal of nano dimension 0
a. yahyazadeh department of chemistry, university of guilan, p.o. box 41335-1914, rasht, iran. v. azimi department of chemistry, university of guilan, p.o. box 41335-1914, rasht, iran

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, 1hnmr and m...

Journal: :iranian chemical communication 2016
batol zakerinasab mohammad ali nasseri hassan hassani

cellulose bonded n-propyl diethylene tetra sulfamic acid (cbpdetsa) was successfully applied as a green and recyclable acidic catalyst for the synthesis of tetrahydrobenzo [a] xanthene-11-one as an important class of potentially bioactive compounds. the products are obtained by the coupling of 2-naphtol , cyclohexadione and aldehyde derivatives in good to high yields (70- 92%) under solvent-fre...

Journal: :iranian journal of science and technology (sciences) 2014
a. r. sardarian

dodecylbenzenesulfonic acid (dbsa) was used as an efficient, cheap and stable brønsted catalyst for acetylation of alcohols and phenols and formylation of alcohols under solvent-free conditions. various primary, secondary and tertiary alcohols were acetylated with acetic anhydride as an acetylating agent under solvent-free conditions in the presence of catalytic amount of dbsa at room temperatu...

Journal: :organic chemistry research 0
hossein eshghi department of chemistry, faculty of science, ferdowsi university of mashhad, mashhad m eftekhar department of chemistry, faculty of sciences, ferdowsi university of mashhad, mashhad 91775-1436, iran. m rahimizadeh department of chemistry, faculty of sciences, ferdowsi university of mashhad, mashhad 91775-1436, iran. m hassanpour department of chemistry, faculty of sciences, ferdowsi university of mashhad, mashhad 91775-1436, iran. m bakavoli department of chemistry, faculty of sciences, ferdowsi university of mashhad, mashhad 91775-1436, iran.

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...

Journal: :chemistry of solid materials 2015
khalil pourshamsian

a  convenient  and  efficient  one-pot  four-component  synthesis  of  1,  2,  4,  5-tetrasubstituted  imidazoles  using  nano  tio2  as  a  recyclable  catalyst  is  reported.  the results  show  that  the  methodology  has  several  advantages  such  as  low  loading  of catalyst,  excellent  yield,  short  reaction  time,  operational  simplicity  and  solvent-free conditions.

3-methyl-1-sulfonic acid imidazolium tetrachloroferrate {[Msim]FeCl4} as an efficient sulfur catalyst was prepared and applied, as an efficient catalyst, for the cross-aldol condensation reaction between cycloalkanones and arylaldehydes to give α,αʹ- bis(arylidene)cycloalkanones in high yields and short reaction times at 75 °C under solvent-free conditions. 3-methyl-1-sulfonic acid imidazolium...

Journal: :iranian chemical communication 0
hassan ghasemnejad-bosra islami azad university, babol-branch amin rostami department of chemistry, faculty of science, university of kurdistan, zip code 66177-15175, sanandaj, iran

n-propylsulfamic acid supported onto magnetic fe3o4 nanoparticles (mnps-psa) was investigated as an efficient and magnetically recoverable catalyst for the one-pot synthesis of substituted coumarins from the reaction of coumarin with variety aromatic aldehydes in high to excellent yield at room temperature under solvent-free conditions. the magnetic nanocatalyst can be readily recovered easily ...

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