نتایج جستجو برای: β cyclodextrain sulfonic acid

تعداد نتایج: 907842  

Ali Reza Badiei Ghodsi Mohammadi Ziarani, Mahbobeh Haddadpour Yeganeh Khaniania

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-P...

A. Badiei F. Aleali Gh. Mohammadi Ziarani, N. Lashgari

Knoevenagel condensation between barbituric acid and aldehyde was investigated in the presence of sulfonic acid functionalized nanoporous silica (SBA-Pr-SO3H) and resulted in the formation of arylidene and bis-arylidene barbiturates. Excellent yields and short reaction times are related to the high efficiency of SBA-Pr-SO3H that the reactions take place easily in its nano-pores. SBA-Pr-SO3H as ...

Abdolkarim Zare, Ahmad Reza Moosavi-Zare Alireza Hasaninejad Maria Merajoddin Masoud Kazem-Rostami Mohammad Mahdi Ahmad-Zadeh Roghayyeh Khanivar

Brønsted acidic ionic liquid triethylamine-bonded sulfonic acid {[Et3N-SO3H]Cl} efficiently catalyzes the one-pot multi-component condensation of 2-naphthol with arylaldehydes and dimedone (5,5-dimethylcyclohexane-1,3-dione) under solvent-free conditions to afford 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-ones in high yields and relatively short reaction times.

2015
A. Kowalczyk M. Ruszkiewicz I. Biskup

The total phenolic content and antioxidant capacity of three apple ciders produced in Poland were examined. The total phenolic content was determined by the Folin-Ciocalteau method and results were expressed in gallic acid equivalents with range from 0.21±0.003 to 0.30±0.004 mg/ml and Trolox equivalents ranging 0.88±0.012 to 1.24±0.015 mg/ml. The antioxidant activity was estimated by two method...

1-Methyl-3-(2-oxyethyl)-1H-Imidazol-3-ium-Borate Sulfonic Acid ([MOEI]-BSA) was easily prepared and used as a new and highly efficient solid acid catalyst for the synthesis of benzimidazole derivatives with high isolated yields. Various substituted benzimidazoles were synthesized by a combination of o-phenylenediamines and aldehydes in the presence of [MOEI]-BSA with excellent yields in water a...

2006
Lei Zhang Sanjeev Mukerjee

Nonfluorinated sulfonic acid membranes are a group of promising candidate materials for the commercialization of proton exchange membrane fuel cell PEMFC technology. However, one of the main obstacles is that the harsh fuel cell environment may originate different modes of degradation and aging processes that result in either chemical or morphological alteration in these membranes. The effect o...

2002
R. A. WEISS P. K. AGARWAL R. D. LUNDBERG

Polystyrenes containing up to about 20 mol % sulfonic acid are reproducibly and readily prepared by the sulfonation of polystyrene at 50°C with acetyl sulfate in 1,2-dichloroethane solution. The metal salts of sulfonated polystyrene possess extremely high melt viscosities and are soluble in single solvents such as toluene and THF only at very low sulfonate levels. Such properties are the result...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید