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 new room-temperature molten salt was prepared based on LiTFSI[LiNC(SO 2CF 3) 2] with OZO(C 3H 5NO 2) which were not reported in literature. Its thermal and electrochemical properties were studied by differential s...The new room-temperature molten salt was prepared based on LiTFSI[LiNC(SO 2CF 3) 2] with OZO(C 3H 5NO 2) which were not reported in literature. Its thermal and electrochemical properties were studied by differential scanning calorimetry, ac impedance spectroscopy and cyclic voltammertry respectively. The results indicated that the structure symmetry of the molecule was depressed and the extent of charges delocalization was expanded, because of introducing oxygen atom of differential electronegativity in OZO molecule. DSC analysis showed that the LiTFSI-OZO molten salt has the excellent thermal stability and its eutectic temperature is below about 223.15 K. Meanwhile, the conductivity of LiTFSI-OZO molten salt at a molar ratio of 1∶4.5 is 0.75×10 -3 S/cm at 298.15 K and 3.50×10 -3 S/cm at 333.15 K. CV analysis showed that the electrochemical window of the sample is about 4 V.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 new room-temperature molten salt was prepared based on LiTFSI[LiNC(SO 2CF 3) 2] with OZO(C 3H 5NO 2) which were not reported in literature. Its thermal and electrochemical properties were studied by differential scanning calorimetry, ac impedance spectroscopy and cyclic voltammertry respectively. The results indicated that the structure symmetry of the molecule was depressed and the extent of charges delocalization was expanded, because of introducing oxygen atom of differential electronegativity in OZO molecule. DSC analysis showed that the LiTFSI-OZO molten salt has the excellent thermal stability and its eutectic temperature is below about 223.15 K. Meanwhile, the conductivity of LiTFSI-OZO molten salt at a molar ratio of 1∶4.5 is 0.75×10 -3 S/cm at 298.15 K and 3.50×10 -3 S/cm at 333.15 K. CV analysis showed that the electrochemical window of the sample is about 4 V.
