نتایج جستجو برای: condensation reaction

تعداد نتایج: 440835  

A series of arylidine barbituric acid derivatives was synthesized by Knoevenagel condensation reaction of aromatic aldehydes with barbituric acid or thiobarbituric acid using dodecylbenzenesulfonic acid as a Brønsted acid-surfactant catalyst in aqueous media. Regardless of the nature of the substitution (electron-donating and -withdrawing), all the reactions were completed within 15-65 min in w...

Journal: :iranian journal of chemistry and chemical engineering (ijcce) 2010
chen grang liu bin tang ying wu ya

5(6)-carboxy-rhodamine 110 isomers were rapidly synthesized by condensation of 3-aminophenol and trimellitic anhydride using microwave irradiation as heating method. after esterification of the two isomers, separation and hydrolyzation provided target products,5-carboxy-rhodamine 110 and 6-carboxy-rhodamine 110, in high yields. the results shows microwave irradiation can effectively reduce the ...

Journal: :iranian journal of chemistry and chemical engineering (ijcce) 2005
ahmad shaabani ayoob bazgir sakineh arab ameri masoumeh sharifi kiasaraie sima samadi

alkali and alkaline earth metals hydrogen sulfate catalyzed the one-pot three component condensation reactions of aldehydes, 1,3-dicarbonyl compounds and urea or thiourea under solvent-free conditions leading to 3,4-dihydropyrimidin-2(1h)-ones in high yields at 80 °c. our results showed that biginelli reaction not only is ph dependent, but the cation of catalyst plays an important role.

Journal: :iranian journal of chemistry and chemical engineering (ijcce) 2013
ahmad shaabani elham farhangi shabnam shaabani

benzazolo [2,1-b]quinazolinones and triazolo[2,1-b]quinazolinones were synthesized in high yields by the condensation reaction of an aldehyde and a cyclic  β-diketone with 2 - aminobenzimidazole, 2 - aminobenzothiazole or 1, 2, 4 - triazole derivatives in 1 - butyl - 3 -methylimidazolium bromide as an ionic liquid under classic heating conditions within 5-60 minutes.

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

1,3-dipolar cycloaddition reaction of 1 mol or 2 mol of dibenzalaceton with 1 mol of non-stabilized azomethinylides generated in situ by decarboxylative condensation of isatin and proline or sarcosine give the novel new spiro-oxindolo(pyrrolizidines/ pyrrolidines) instead of bis-spirooxindolo( pyrrolizidines/ pyrrolidines).

A practical and new method for the synthesis oxindole substituted pyrrolo[2,3-d]pyrimidines by the condensation of isatin, acetophenone and 6-amino-uracil under ultrasound irradiation conditions at 60 °C was described. The reaction was developed via a sequential tandem process to afford the oxindole substituted pyrrolo[2,3-d]pyrimidines in good to excellent yields. All reactions performed effic...

Journal: :Molecules 2009
Chen-Jiang Liu Ji-De Wang

A simple, efficient procedure for the one-pot Biginelli condensation reaction of aldehydes, beta-ketoesters and urea or thiourea employing copper(II) sulfamate as a novel catalyst is described. Compared to the classical Biginelli reaction conditions, the present method has the advantages of good yields, short reaction times and experimental simplicity.

Journal: :iranian chemical communication 0
seyyedeh cobra azimi university of guilan kurosh rad-moghadam university of guilan

a practical and new method for the synthesis oxindole substituted pyrrolo[2,3-d]pyrimidines by the condensation of isatin, acetophenone and 6-amino-uracil under ultrasound irradiation conditions at 60 °c was described. the reaction was developed via a sequential tandem process to afford the oxindole substituted pyrrolo[2,3-d]pyrimidines in good to excellent yields. all reactions performed effic...

Journal: :iranian chemical communication 2015
amit s. waghmare shivaji s. pandit

the three components one pot synthesis of 2-amino-4h-benzo-[b] -pyran derivatives were obtained in good to excellent yields within short reaction time by condensing dimedone, aldehydes and malanonitrile or ethylcyanoacetate using a catalytic amount of (diacetoxyiodo)benzene as hypervalent iodine in aqueous ethanol under reflux conditions have been discussed. this aqua mediated knoevenagel-cyclo...

Journal: :journal of nanostructures 2015
a. hashemzehi-goonaki j. saffari

in this work firstly fe2o3 nanoparticles were synthesized via a simple chemical method. properties of the product were examined by x-ray diffraction pattern (xrd), scanning electron microscope (sem) and fourier transform infrared (ft-ir) spectroscopy. vibrating sample magnetometer (vsm) shows nanoparticles exhibit ferromagnetic behavior. to continue some of the 2-naphthol condensed 1,3-oxazinon...

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