نتایج جستجو برای: acid base catalyst

تعداد نتایج: 1012226  

Journal: :iranian journal of chemistry and chemical engineering (ijcce) 2010
ghodsi mohammadi ziarani ali reza badiei yeganeh khaniania mahbobeh haddadpour

sulfonic acid functionalized sba-15 (sba-pr-so3h) as a new nanoporous acid catalyst was used in the one-pot synthesis of polyhydroquinolines derivatives via the hantzsch four component condensation reaction of aldehydes, b-ketoesters, dimedone and ammonium acetate under solvent free conditions with short reaction time in excellent yields. sba-pr-so3h was proved to be an efficient heterogeneous ...

Journal: :Journal of environmental sciences 2013
Ben Li Cuiping Wang Guang Chen Zhiqiang Zhang

Highly active, air-stable and water-soluble palladium-phosphinous acid complexes have been applied to Suzuki cross-coupling reaction of heteroaryl bromides under mild conditions in water/alcoholic solvents. Suzuki cross-coupling reaction of heteroaryl bromides with phenylboronic acid occurred efficiently using palladium phosphinous acid complexes (POPd) and phase transfer catalyst (tetrabutylam...

Journal: :Catalysis Today 2021

Ce oxide-based catalysts with different molar ratio of Co/Ce (denoted as CoCe-x, x represents the Co to ratio) were examined catalyst 5-hydroxymethylfurfural (5-HMF) oxidation 2,5-furandicarboxylic acid (FDCA). The ratio, amount and reaction temperature all have remarkable effects on yield selectivity. Complete conversion 5-HMF 86.3 % selectivity FDCA has been achieved over CoCe-0.15 at 130 °C ...

2014
Arpita Kulshreshtha C. P. Shinde

Esters of pentavalent phosphorus acids are the most important class of organophosphorus (OP) compounds. They are derivatives of the following three parent acids, viz. phosphinic acid, phosphonic acid and phosphoric acid. Phosphorus compounds may be classified as anhydride, aliphatic, aromatic, and heterocyclic. The majority of OP insecticides are derivatives of phosphoric acid. Triesters of pho...

Journal: :iranian journal of catalysis 2014
sami sami maryam norollahi sara miri

easily synthesized1-methyl-3-(2-oxyethyl)-1h-imidazol-3-ium-borate sulfonic acid {[moei]-bsa} as a novel catalyst efficiently promoted the synthesis of quinoxaline derivatives via condensation of various diamines with 1,2-dicarbonyl compounds at room temperature conditions in ethanol. this research provides a new method for the synthesis of quinoxalines in good to excellent yields with little c...

Nano silica sulfuric acid as a solid acid, was described to be an effective catalyst for one-pot three-component reaction of kojic acid, aryl aldehydes and indoles for the preparation of 2-substituted aryl (indolyl) kojic acid derivatives. The catalyst was prepared by combination of chlorosulfonic acid to nano silica gel. The size of nanoparticles were observed with SEM.All prepared compounds w...

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: :organic chemistry research 0
habib ollah foroughi department of scince, islamic azad university, fasa branch ali khalafi-nezhad department of chemistry, shiraz university, shiraz,71454, i.r.iran

the silica boron sulfuric acid nanoparticles (sbsans) as an efficient heterogeneous solid acid catalyst with both brønsted and lewis acidic sites catalyzed the preparation of bis-4-hydroxycoumarin derivatives using reaction of aldehydes and 4-hydroxycoumarin under mild and solvent-free condition at room temperature. this new and efficient methodology has advantages in comparison with currently ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید