نتایج جستجو برای: acidic catalyst
تعداد نتایج: 77393 فیلتر نتایج به سال:
In this paper, the synthesis of various enaminones from the reaction of 3-aminocoumarin and ethyl-2,4-dioxo-4-arylbutanoate in the presence of p-toluene sulfonic acid is reported. The reaction was examined under different solvents and catalytic systems, which clearly proved the importance of acidic catalyst in this organic transformation. This work was also accompanied by density functional the...
Au nanoparticles supported on ZrO2 enhance its surface acidic/basic properties to produce a high yield of methanol via the hydrogenation CO2. Amorphous ZrO2-supported 0.5–1 wt.% catalysts were synthesized by two methods, namely deposition precipitation (DP) and impregnation (IMP), characterized variety techniques, evaluated in process CO2 methanol. The DP-method highly advantageous over IMP-met...
A series of 2-amino pyridine-3-carbinitrile derivatives incorporated coumarin moiety has developed via multicomponent condensation of 3-acetyl-2H-chromen-2-one, arylaldehydes, malononitrile and ammonium acetate utilizing Brønsted acidic ionic liquid, (4-sulfobutyl)tris(4-sulfophenyl)phosphonium hydrogen sulfate as catalyst under solvent-free conditions. Good yields, short reaction times, straig...
hydrogenation reaction with n-heptane on pt/al2o3 catalyst was investigated under the steady state condition in a fixed bed reactor. the catalyst was prepared under a variety of conditions, but the one chosen was non-acidic that is not considered a hydrocracking catalyst. the main objective was to vary the selectivity of n-heptane as a function of reaction variables especially the partial press...
in this work, the ionic liquid triethylamine-bonded sulfonic acid {[et3n–so3h]cl}, n,n-diethyl-n-sulfoethanammonium chloride was used as a green acidic homogeneous catalyst to synthesis of 3,4-dihydropyrimidin-2(1h)-ones and 3,4-dihydropyrimidin-2(1h)-thiones as two categories of heterocycles, from aldehyde, dicarbonyl compound and urea or thiourea throughout the one-pot three components cycloc...
A series of 2-amino pyridine-3-carbinitrile derivatives incorporated coumarin moiety has developed via multicomponent condensation of 3-acetyl-2H-chromen-2-one, arylaldehydes, malononitrile and ammonium acetate utilizing Brønsted acidic ionic liquid, (4-sulfobutyl)tris(4-sulfophenyl)phosphonium hydrogen sulfate as catalyst under solvent-free conditions. Good yields, short reaction times, straig...
iron is essential to erythrocyte oxygen transport and is a catalyst for oxidative metabolism in all cells. iron is absorbed by the duodenum and requires an acidic environment for optimal absorption. iron is found for 70% in erythrocytes, and 30% in storage, and a small amount in myoglobin and cytochromes. iron supplementation reduces anemia in breastfed infants and increases in significant dose...
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