Microporous heteropolyoxometalates Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 were synthesized by a sol\|gel technique and characterized by IR, UV\|Vis, BET adsorption/desorption isotherm. The structural fr...Microporous heteropolyoxometalates Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 were synthesized by a sol\|gel technique and characterized by IR, UV\|Vis, BET adsorption/desorption isotherm. The structural frameworks of Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\} are preserved within the silica networks. Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 are a kind of polyoxometalate\|silica gel hybrids with uniform micropores of ca. 0.65 nm. They show a high catalytic activity for oxidation reaction of benzyl alcohol by H\-2O\-2(30%) in liquid\|solid systems and product selectivity for benzaldehyde(>96%). The highest activity is observed at \%x\%=2.5 in Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 and little formation of benzoic acid and a more deeply oxidized product is observed.展开更多
An efficient and simple method for the synthesis of chalcones was reported.In the presence of sulfurous oxychloride,the cross-aldol condensation of acetone and benzaldehyde was catalyzed by the anhydrous ethanol with ...An efficient and simple method for the synthesis of chalcones was reported.In the presence of sulfurous oxychloride,the cross-aldol condensation of acetone and benzaldehyde was catalyzed by the anhydrous ethanol with good yields(60%-95%)under mild condition.The best reaction condition was studied.The reaction mechanism was also discussed.展开更多
文摘Microporous heteropolyoxometalates Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 were synthesized by a sol\|gel technique and characterized by IR, UV\|Vis, BET adsorption/desorption isotherm. The structural frameworks of Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\} are preserved within the silica networks. Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 are a kind of polyoxometalate\|silica gel hybrids with uniform micropores of ca. 0.65 nm. They show a high catalytic activity for oxidation reaction of benzyl alcohol by H\-2O\-2(30%) in liquid\|solid systems and product selectivity for benzaldehyde(>96%). The highest activity is observed at \%x\%=2.5 in Cs\-\%x\%H\-\{5-\%x\%\}PW\-\{10\}V\-2O\-\{40\}/SiO\-2 and little formation of benzoic acid and a more deeply oxidized product is observed.
文摘An efficient and simple method for the synthesis of chalcones was reported.In the presence of sulfurous oxychloride,the cross-aldol condensation of acetone and benzaldehyde was catalyzed by the anhydrous ethanol with good yields(60%-95%)under mild condition.The best reaction condition was studied.The reaction mechanism was also discussed.