Imidazolium-coated periodic mesoporous organosilicas for selective synthesis of electron-deficient 2-arylbenzo[d]oxazoles

【作者】 崔荷珍； 侯秀峰；

【Author】 He-Zhen Cui;Xiu-Feng Hou;Department of Chemistry, Fudan University;

【机构】 复旦大学化学系；

【摘要】 Support materials apply to the changeover of catalytic performance for reaction sites is still far-reaching.^1-3 Based on our previous work, ^4-6 we prepared and confirmed series of hydrophobic ethyl bridges（contents range from 5 % to 35 %） modulated periodic mesoporous organosilica（PMO） fixed with 1-methyl-3-butyl-1 H-imidazol-3-iumiodide（MBIm）. Here, MBIm-PMO-15 displayed the best performance for most of benzaldehyde with strong electrondeficient groups to 2-arylbenzoxazole giving > 90 % conversion, while was poor in electron-donating process. After coating in mesoporous support, activity of MBIm was total reversal in the same reaction system. Further, FT-IR adsorption and UV-vis detection tests reveal that mesoporous silica interfacial prefer adsorbing electron-deficient substrates to electron-donating ones. Importantly, such special supports surface driven substrate-catalyst selective adsorption, could act as effective means to get special target product.更多还原

【Abstract】 Support materials apply to the changeover of catalytic performance for reaction sites is still far-reaching.^1-3 Based on our previous work, ^4-6 we prepared and confirmed series of hydrophobic ethyl bridges（contents range from 5 % to 35 %） modulated periodic mesoporous organosilica（PMO） fixed with 1-methyl-3-butyl-1 H-imidazol-3-iumiodide（MBIm）. Here, MBIm-PMO-15 displayed the best performance for most of benzaldehyde with strong electrondeficient groups to 2-arylbenzoxazole giving > 90 % conversion, while was poor in electron-donating process. After coating in mesoporous support, activity of MBIm was total reversal in the same reaction system. Further, FT-IR adsorption and UV-vis detection tests reveal that mesoporous silica interfacial prefer adsorbing electron-deficient substrates to electron-donating ones. Importantly, such special supports surface driven substrate-catalyst selective adsorption, could act as effective means to get special target product.更多还原