Amino-functionalized SBA-15(SBA-Pr-NH2) has been used as a new basic nanocatalyst in the one-pot synthesis of spirooxindole derivatives via the three-component condensation reaction of isatins,activated methylene reag...Amino-functionalized SBA-15(SBA-Pr-NH2) has been used as a new basic nanocatalyst in the one-pot synthesis of spirooxindole derivatives via the three-component condensation reaction of isatins,activated methylene reagents,and dimedone in an aqueous medium.SBA-Pr-NH2 has been established as an efficient heterogeneous nanoporous solid basic catalyst(pore size of 6 nm) that can be easily handled and removed from the reaction mixture by simple filtration,and also recovered and reused without noticeable loss of reactivity.展开更多
A Cr/SBA-16 catalyst was prepared using Cr（NO3）3 as a precursor and mesoporous silica SBA-16 as a support via a simple impregnation method. The catalyst was characterized using wide-angle X-ray diffraction （XRD）, ...A Cr/SBA-16 catalyst was prepared using Cr（NO3）3 as a precursor and mesoporous silica SBA-16 as a support via a simple impregnation method. The catalyst was characterized using wide-angle X-ray diffraction （XRD）, low-angle XRD, N2 adsorption-desorption, transmission electron microscopy, and ultraviolet-visible spectroscopy. The catalyst activity was investigated in the direct bydroxylation of benzene to phenol using H2O2 as the oxidant. Various operating variables, namely reaction temperature, reaction time, amount of H2O2, and catalyst dosage, were optimized using central composite design combined with response surface methodology （RSM）. The results showed that the correla- tion between the independent parameters and phenol yield was represented by a second-order polynomial model. The high correlation coefficient （R2）, i.e., 0.985, showed that the data predicted using RSM were in good agreement with the experimental results. The optimization results also showed that high selectivity for phenol was achieved at the optimized values of the operating variables： reaction temperature 324 K, reaction time 8 h, H2O2 content 3.28 mL, and catalyst dosage 0.09 g. This study showed that RSM was a reliable method for optimizing process variables for benzene hydroxylation to phenol.展开更多
基金supported by the Research Councils at Alzahra University and university of Tehran
文摘Amino-functionalized SBA-15(SBA-Pr-NH2) has been used as a new basic nanocatalyst in the one-pot synthesis of spirooxindole derivatives via the three-component condensation reaction of isatins,activated methylene reagents,and dimedone in an aqueous medium.SBA-Pr-NH2 has been established as an efficient heterogeneous nanoporous solid basic catalyst(pore size of 6 nm) that can be easily handled and removed from the reaction mixture by simple filtration,and also recovered and reused without noticeable loss of reactivity.
基金the University of Tehran for financial support of this work
文摘A Cr/SBA-16 catalyst was prepared using Cr（NO3）3 as a precursor and mesoporous silica SBA-16 as a support via a simple impregnation method. The catalyst was characterized using wide-angle X-ray diffraction （XRD）, low-angle XRD, N2 adsorption-desorption, transmission electron microscopy, and ultraviolet-visible spectroscopy. The catalyst activity was investigated in the direct bydroxylation of benzene to phenol using H2O2 as the oxidant. Various operating variables, namely reaction temperature, reaction time, amount of H2O2, and catalyst dosage, were optimized using central composite design combined with response surface methodology （RSM）. The results showed that the correla- tion between the independent parameters and phenol yield was represented by a second-order polynomial model. The high correlation coefficient （R2）, i.e., 0.985, showed that the data predicted using RSM were in good agreement with the experimental results. The optimization results also showed that high selectivity for phenol was achieved at the optimized values of the operating variables： reaction temperature 324 K, reaction time 8 h, H2O2 content 3.28 mL, and catalyst dosage 0.09 g. This study showed that RSM was a reliable method for optimizing process variables for benzene hydroxylation to phenol.
