نتایج جستجو برای: solvent free condition

تعداد نتایج: 857817  

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

an efficient method for the friedel–crafts acylation of a wide range of aromatic compounds in good to excellent yields under solvent-free conditions, using iron zirconium phosphate (zpfe) was investigated. the catalyst is easy to prepare and shows interesting catalytic properties. the catalyst was characterized by some instrumental techniques such as xrd, icp-oes, sem and tem. a wide variety of...

Journal: :iranian journal of catalysis 2011
ahmad reza momeni somayeh bagheri

p2o5-sio2 (30% w/w) was found to be a useful catalyst for the synthesis of various 2-substituted aryl benzimidazoles under solvent-less and in solvent conditions from o-phenylenediamine and aldehydes. the products were directly recrystallized from methanol.

Journal: :iranian journal of catalysis 2014
abdol reza hajipour ghobad azizi

a variety of alcohols readily add to 3,4-dihydro-2h-pyran under solvent free conditions in the presence of catalytic amount of acidic ionic liquid [et3n(ch2)4so3h][ots] to afford the corresponding tetrahydropyranyl ethers in good to excellent yields at room temperature. the use of this procedure allows easy separation of the desired products from ionic liquid and recycling the ionic liquid. som...

Journal: :international journal of bio-inorganic hybrid nanomaterials 0

one of the most important goals in medicinal chemistry is the development of new techniques and new heterocyclic compounds with pharmaceutical activity. the present study aimed to use a method for the synthesis of some 1,2-dihydro-1-arylnaphtho [1,2-e] [1,3] oxazine-3-ones. the question this study tried to answer was this reaction can be performed in present of nano-fe2o3 as an acid catalyst an...

A simple, efficient, and cost-effective procedure for the N-tert-butoxycarbonylation and N-formylation of amines (primary, secondary) respectively, with di-tert-butyl dicarbonate and 85% aqueous formic acid under solvent-free condition using B(OSO3H)3/SiO2 (SBSA) as a heterogeneous and recyclable catalyst has been developed. We demonstrated that the resulting catalyst is applicable to various a...

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: :journal of sciences, islamic republic of iran 2014
b. pouramiri e. tavakolinejad kermany h. khajesamani h. khabazzadeh

an improved, simple, and facile synthesis of 3,4-dihydropyrimidin-2(1h)-ones by employing three-component, one-pot condensation reaction of β-keto ester, aromatic aldehydes, and urea or n-methylurea using lacl3/clch2cooh as an inexpensive and green chemistry catalyst system under solvent-free conditions described. compared with the classicalbiginelli reaction conditions, this method has the adv...

Journal: :iranian chemical communication 0
rahimeh hajinasiri department of chemistry, islamic azad university, qaemshahr branch, p.o. box 163, qaemshahr, iran sanaz baravardeh department of chemistry, qaemshahr branch, islamic azad university, p.o. box 163, qaemshahr, iran sobhan rezayati department of chemistry, payame noor university, po box 19395-4697, tehran, iran

derivatives of thiazolidinone ring systems are known to act as anti-hiv infections , analgesic, anti-bacterial, anti-convulsant, anti parasitic, potential anti-inflammatory and herbicidal agents. due biological activities of thiazolidinones ring, several methods for their synthesis have been illustrated in literature. imidazolidine-2-thiones were synthesized by the oxidative cyclization of 1-be...

Journal: :journal of particle science and technology 0
zinat gordi department of chemistry, payame noor university, tehran, iran. mohammad vazan department of chemistry, payame noor university, tehran, iran.

a series of tri- and tetra- substituted imidazoles were synthesized from benzyl, aldehyde and ammonium acetate in the presence of zeolite as an ecofriendly reusable catalyst under microwave irradiation in the absence of solvent. the yields are high to excellent and the use of microwave irradiation reduces reaction times to few minute.

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...

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