نتایج جستجو برای: solid phase and recyclable basic catalyst
تعداد نتایج: 16989339 فیلتر نتایج به سال:
An efficient, simple and convenient route is described for the synthesis of biscoumarin (3,3'-(arylmethylene) bis (4-hydroxy-2H-chromen-2-one)) by using of recyclable catalyst TiO2@KSF. In this Method, we synthesis biscoumarin derivatives via 3multi-component reactions (3MCRs) of two equivalent 4-hydroxycoumarin with one equivalent of aromatic aldehydes using 20 mg nano TiO2@KSF as homogeneous ...
silica-bonded n-propyldiethylenetriamine sulfamic acid (spdtsa) is employed as a recyclable heterogeneous solid acid catalyst for the synthesis of benzopyrano[2,3-d]pyrimidines through one-pot condensation reaction of salicylaldehydes, malononitrile and secondary amines at room temperature under solvent-free conditions. spdtsa showed much the same efficiency when used in consecutive reaction ...
the one-pot, multi-component synthesis of 4,4′-(arylmethylene)bis(1h-pyrazol-5-ols) by tandem knoevenagel-michael reaction of phenylhydrazine, ethyl acetoacetate and aldehydes in the presence of silica-bonded n-propylpiperazine sulfamic acid (sbppsa) as a recyclable solid acid catalyst was reported. sbppsa showed much the same efficiency when used in consecutive reaction runs.
An efficient and facile synthesis of fatty acid methyl esters (FAMEs) using sunflower oil and methanol has been carried out in the presence of a solid base Mg-Al-CO3 hydrotalcite heterogeneous catalyst. This protocol promotes the environment friendly conditions as the hydrotalcites are non toxic, recyclable, takes less reaction time and is easy to work up. The hydrotalcite showed high activity ...
silica-bonded n-propyldiethylenetriamine (7) is employed as a recyclable heterogeneous solid base catalyst for the synthesis of 2-amino-3,5-dicarbonitrile-6-thiopyridines through pseudo four-component condensation reaction between aromatic aldehydes, malononitrile, and 2-amino-thiophenol in refluxing ethanol. silica-bonded n-propyldiethylenetriamine showed much the same efficiency when used in ...
The one-pot, multi-component synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ols) by tandem Knoevenagel-Michael reaction of phenylhydrazine, ethyl acetoacetate and aldehydes in the presence of silica-bonded N-propylpiperazine sulfamic acid (SBPPSA) as a recyclable solid acid catalyst was reported. SBPPSA showed much the same efficiency when used in consecutive reaction runs.
A convenient and efficient methodology for the synthesis of densely substituted pyrrole-fused isocoumarins, which employs solid-supported silica sulfuric acid (SSA) as catalyst, has been developed. When the mixture of ninhydrin adducts of acetylacetone/ethyl acetoacetate and primary amines was heated on the solid surface of SSA under solvent-free conditions, the pyrrole-fused isocoumarins were ...
< p>Mg-Fe bi-metal oxide was prepared and utilized as a magnetized renewable solid base catalyst for formation of 2-aminothiophenes by means of Gewald’s reaction. The prepared heterogeneous basic solid catalyst can be separated by a magnet and reused without considerable wastage in this activity. The structure of the aforementioned magnetized basic nano-catalyst was studied by XRD (X-ray diffra...
The design and development of metal-cluster-based heterogeneous catalysts with high activity, selectivity, and stability under solution-phase reaction conditions will enable their applications as recyclable catalysts in large-scale fine chemicals production. To achieve these required catalytic properties, a heterogeneous catalyst must contain specific catalytically active species in high concen...
sulfonic acid-based precursors (sap) play an important role in tailoring mesoporous silica’s and convert them to a solid acid catalyst with a bronsted-type nature. these kinds of solid acids contribute to sustainable and green chemistry by their heterogeneous, recyclable, and high efficiency features. therefore, knowing the properties and reactivity of saps can guide us to manufacture a sulfona...
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