A hierarchical microporous-mesoporous metal-organic framework of HKUST-l（Cu）-encapsulated phosphotungstic acid （HPW） material, referred to as HPWs@Meso-HKUST-1, is prepared by a one-pot synthesis method using cety...A hierarchical microporous-mesoporous metal-organic framework of HKUST-l（Cu）-encapsulated phosphotungstic acid （HPW） material, referred to as HPWs@Meso-HKUST-1, is prepared by a one-pot synthesis method using cetyltrimethylammonium bromide as the supramolecular template. The addition of HPWs to the synthesis mixture of hierarchical porous HKUST-1 results in the direct encapsulation of HPWs inside the mesopores of the HKUST-1 structure, with a homogeneous distribution over the HKUST-1 crystals, which is confirmed by XRD, FT-IR, N2 adsorption, UV-Vis DRS, and TEM. FT-IR-CO adsorption experiments indicated that additional Lewis acid sites were present in the HPWs@Meso-HKUST-1 sample. The novel heterogeneous catalyst demonstrates excellent catalytic performance for the selective oxidation of cyclopentene （CPE） to glutaraldehyde CGA） using tert-butyl hydroperoxide and acetonitrile （MeCN） as the oxidant and solvent, respectively. The high activity of the catalyst is attributed to the mesostructure of the catalyst and the nature and appropriate abundance of the HPWs--being highly dispersed with the addition of Lewis sites. After a reaction for 36 h, the 30% wt% HPWs@Meso-HKUST-1 catalyst exhibits a CPE conversion of 92.5% and a high GA yield of 73%. Furthermore, the HPWs@Meso-HKUST-1 material is sufficiently stable to prevent the leaching of HPWs, and behaves as a true heterogeneous catalyst that can be repeatedly recycled without sustaining a loss of activity and selectivity in the selective oxidation of CPE.展开更多
The crystal structure of the title compound C16H18NO2+·C7H7SO3-·2H2O, (C23H29NSO7, Mr=463.53) has been determined by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system wi...The crystal structure of the title compound C16H18NO2+·C7H7SO3-·2H2O, (C23H29NSO7, Mr=463.53) has been determined by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system with space group P21/n, a=8.101(1), b=8.958(2), c=33.281(5)?,β= 94.910(1)(, V=2406.3(7)?3, Z=4, Dc=1.279g/cm3, μ=0.176mm-1, F(000)=984, final R=0.0409, and Rw=0.0860 for 4401 independent reflections. The result shows that in the crystal structure of the title compound the planar cations have two configurations with equal occupation ratio and are antiparally packed through π…π interactions. Similar packing energies in A and B are probably the main factor that leads to the disorder structure.展开更多
以亚硫酸氢钠-过硫酸铵为引发体系通过自由基聚合合成了丙烯酸(AA)/丙烯酰胺(AM)/(1-二甲氨基烯丙基)-膦酸(DMAAPA)/二乙基二烯丙基溴化铵(DDAB)四元共聚物。最佳反应条件为:m(AA)∶m(AM)∶m(DMAAPA)∶m(DDAB)=4.0∶6.0∶0.015∶0.020,w...以亚硫酸氢钠-过硫酸铵为引发体系通过自由基聚合合成了丙烯酸(AA)/丙烯酰胺(AM)/(1-二甲氨基烯丙基)-膦酸(DMAAPA)/二乙基二烯丙基溴化铵(DDAB)四元共聚物。最佳反应条件为:m(AA)∶m(AM)∶m(DMAAPA)∶m(DDAB)=4.0∶6.0∶0.015∶0.020,w(引发剂)=0.3%,pH=7,反应温度为40℃,单体总质量分数为20%。对AA/AM/DMAAPA/DDAB的分子结构进行了IR、1 H NMR表征。研究表明:该共聚物具有良好的耐温、耐盐、抗剪切性能;当该共聚物质量分数为1.0%时,对蒙脱土的防膨率达到84.05%,与质量分数1.0%的KCl复配后测得的防膨率达到95.04%。展开更多
基金supported by the Plan of Nature Science Fundamental Research in Henan University of Technology (2013JCYJ09)the Fundamental Research Funds for the Henan Provincial Colleges and Universities(2014YWQQ13)the National Natural Science Foundation of China (20903035,21373054)~~
文摘A hierarchical microporous-mesoporous metal-organic framework of HKUST-l（Cu）-encapsulated phosphotungstic acid （HPW） material, referred to as HPWs@Meso-HKUST-1, is prepared by a one-pot synthesis method using cetyltrimethylammonium bromide as the supramolecular template. The addition of HPWs to the synthesis mixture of hierarchical porous HKUST-1 results in the direct encapsulation of HPWs inside the mesopores of the HKUST-1 structure, with a homogeneous distribution over the HKUST-1 crystals, which is confirmed by XRD, FT-IR, N2 adsorption, UV-Vis DRS, and TEM. FT-IR-CO adsorption experiments indicated that additional Lewis acid sites were present in the HPWs@Meso-HKUST-1 sample. The novel heterogeneous catalyst demonstrates excellent catalytic performance for the selective oxidation of cyclopentene （CPE） to glutaraldehyde CGA） using tert-butyl hydroperoxide and acetonitrile （MeCN） as the oxidant and solvent, respectively. The high activity of the catalyst is attributed to the mesostructure of the catalyst and the nature and appropriate abundance of the HPWs--being highly dispersed with the addition of Lewis sites. After a reaction for 36 h, the 30% wt% HPWs@Meso-HKUST-1 catalyst exhibits a CPE conversion of 92.5% and a high GA yield of 73%. Furthermore, the HPWs@Meso-HKUST-1 material is sufficiently stable to prevent the leaching of HPWs, and behaves as a true heterogeneous catalyst that can be repeatedly recycled without sustaining a loss of activity and selectivity in the selective oxidation of CPE.
文摘The crystal structure of the title compound C16H18NO2+·C7H7SO3-·2H2O, (C23H29NSO7, Mr=463.53) has been determined by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system with space group P21/n, a=8.101(1), b=8.958(2), c=33.281(5)?,β= 94.910(1)(, V=2406.3(7)?3, Z=4, Dc=1.279g/cm3, μ=0.176mm-1, F(000)=984, final R=0.0409, and Rw=0.0860 for 4401 independent reflections. The result shows that in the crystal structure of the title compound the planar cations have two configurations with equal occupation ratio and are antiparally packed through π…π interactions. Similar packing energies in A and B are probably the main factor that leads to the disorder structure.
文摘以亚硫酸氢钠-过硫酸铵为引发体系通过自由基聚合合成了丙烯酸(AA)/丙烯酰胺(AM)/(1-二甲氨基烯丙基)-膦酸(DMAAPA)/二乙基二烯丙基溴化铵(DDAB)四元共聚物。最佳反应条件为:m(AA)∶m(AM)∶m(DMAAPA)∶m(DDAB)=4.0∶6.0∶0.015∶0.020,w(引发剂)=0.3%,pH=7,反应温度为40℃,单体总质量分数为20%。对AA/AM/DMAAPA/DDAB的分子结构进行了IR、1 H NMR表征。研究表明:该共聚物具有良好的耐温、耐盐、抗剪切性能;当该共聚物质量分数为1.0%时,对蒙脱土的防膨率达到84.05%,与质量分数1.0%的KCl复配后测得的防膨率达到95.04%。
