[γ-1,2-H2SiV2W10O40] Immobilized on Surface-Modified SiO2 as a Heterogeneous Catalyst for Liquid-Phase Oxidation with H2O2
作者:Jun Kasai、Yoshinao Nakagawa、Sayaka Uchida、Kazuya Yamaguchi、Noritaka Mizuno
DOI:10.1002/chem.200501414
日期:2006.5.15
with TBA-I. The oxidation can be stopped immediately by removal of the solid catalyst, and vanadium and tungsten species can hardly be found in the filtrate after removal of the catalyst. These results rule out any contribution to the observed catalysis from vanadium and tungsten species that leach into the reaction solution, which means that the observed catalysis is truly heterogeneous in nature. In
通过将N-辛基二氢咪唑鎓阳离子片段共价锚定在SiO2(表示为1-SiO2)上,可以合成有机-无机杂化载体。该改性的载体通过固态13C,29Si和31P NMR光谱,IR光谱和元素分析进行表征。结果表明,二氢咪唑骨架的结构保留在SiO2的表面上。改性的载体可以充当良好的阴离子交换剂,使催化活性的多金属氧酸盐阴离子[γ-1,2-H2SiV2W10O40] 4-(I)通过化学计量的阴离子交换(表示为I / 1- SiO2)。红外交换和51V NMR光谱证实,阴离子交换后阴离子I的结构得以保留。烯烃和硫化物氧化的催化性能,用I / 1-SiO2研究了用过氧化氢(相对于底物仅一个当量)作为唯一氧化剂的方法。这种负载型催化剂显示出高的立体定向性,非对映选择性,区域选择性和高效率的过氧化氢用于各种烯烃和硫化物的氧化,而不会损失相应的I均相类似物(即四-n -I的丁基丁基铵盐,TBA-1),尽管该比率