3,4-Dihydropyrimidin-2-(1H)-ones were synthesized in high yields by a one-pot cyclocondensation of aldehyde,1,3-dicarbonyl compound,and urea or thiourea using copper o-toluenesulfonate as a catalyst under solvent-free...3,4-Dihydropyrimidin-2-(1H)-ones were synthesized in high yields by a one-pot cyclocondensation of aldehyde,1,3-dicarbonyl compound,and urea or thiourea using copper o-toluenesulfonate as a catalyst under solvent-free conditions at 90℃.Effects of molar ratio of reactants,amount of catalyst,and reaction temperature on the yields of 3,4-dihydropyrimidin-2-(1H)-ones were investigated.The results showed that at the condition of naldehyde∶n1,3-dicarbonyl compounds∶nurea(or thiourea)=1∶1.2∶1.5,1 mol% catalyst(molar percent of aldehyde),2.0 h at 90℃,the yields of products were 51-96%.After reaction,the catalyst could be reused for four times without distinct loss of catalytic activity.展开更多
The synergistic extraction of lanthanide ions(La3+,Pr3+,Nd3+,Gd3+,Dy3+)by Bis（1′-phenyl-3′-mcthyl-5′-pyrazolonc-4′-yl）Phthaldionc（H2BPMOPP or H2A）with 8-Hydroxyquinolinc（HOx）from nitric acid aolution was stu...The synergistic extraction of lanthanide ions(La3+,Pr3+,Nd3+,Gd3+,Dy3+)by Bis（1′-phenyl-3′-mcthyl-5′-pyrazolonc-4′-yl）Phthaldionc（H2BPMOPP or H2A）with 8-Hydroxyquinolinc（HOx）from nitric acid aolution was studied.The synergistic coefficient for La3+ was 8.1.The composition of the extracted compound was shown to be LaA·HA·HOx.The pH1/2 values for La3+,Pr3+,Nd3+,Gd3+ and Dy3+ were 4.20,3.73,3.49,3.30 and 3.01 respectively.The extraction equilibrium constants,enthalyp change and entropy change of the reaction also were calculated.展开更多
文摘3,4-Dihydropyrimidin-2-(1H)-ones were synthesized in high yields by a one-pot cyclocondensation of aldehyde,1,3-dicarbonyl compound,and urea or thiourea using copper o-toluenesulfonate as a catalyst under solvent-free conditions at 90℃.Effects of molar ratio of reactants,amount of catalyst,and reaction temperature on the yields of 3,4-dihydropyrimidin-2-(1H)-ones were investigated.The results showed that at the condition of naldehyde∶n1,3-dicarbonyl compounds∶nurea(or thiourea)=1∶1.2∶1.5,1 mol% catalyst(molar percent of aldehyde),2.0 h at 90℃,the yields of products were 51-96%.After reaction,the catalyst could be reused for four times without distinct loss of catalytic activity.
文摘The synergistic extraction of lanthanide ions(La3+,Pr3+,Nd3+,Gd3+,Dy3+)by Bis（1′-phenyl-3′-mcthyl-5′-pyrazolonc-4′-yl）Phthaldionc（H2BPMOPP or H2A）with 8-Hydroxyquinolinc（HOx）from nitric acid aolution was studied.The synergistic coefficient for La3+ was 8.1.The composition of the extracted compound was shown to be LaA·HA·HOx.The pH1/2 values for La3+,Pr3+,Nd3+,Gd3+ and Dy3+ were 4.20,3.73,3.49,3.30 and 3.01 respectively.The extraction equilibrium constants,enthalyp change and entropy change of the reaction also were calculated.
