A facile approach for the first synthesis of ocimarin, naturally occurring coumarins, was developed by employing a cerium (III) chloride heptahydrate-catalyzed Pechmann condensation of phenols and β-keto esters in ...A facile approach for the first synthesis of ocimarin, naturally occurring coumarins, was developed by employing a cerium (III) chloride heptahydrate-catalyzed Pechmann condensation of phenols and β-keto esters in a solvent-free system as key step, by which ocimarin was achieved by three steps starting from acetylacetic ether and resorcinol with total yield 23.2%. All structures of new compounds were confirmed by IR, ^1H NMR and MS.展开更多
The equilibrium solubility of CsCl CeCl 3 HCl(11%) H 2O quaternary system at 25 ℃ has been determined by the physic chemical analysis method, and the phase diagram was plotted. Two new double salts 3CsCl·C...The equilibrium solubility of CsCl CeCl 3 HCl(11%) H 2O quaternary system at 25 ℃ has been determined by the physic chemical analysis method, and the phase diagram was plotted. Two new double salts 3CsCl·CeCl 3·3H 2O and CsCl·CeCl 3·4H 2O obtained from the complicated system were identified and characterized by XRD, TG DTA, DSC, UV and fluorescence spectroscopy. Studies on the fluorescence excitation and emission show that 3CsCl·CeCl 3·3H 2O and CsCl·CeCl 3·4H 2O have upconversion luminescence of infrared visible range, and the upconversion emission intensity increases with the increase of ratio of CeCl 3 in CsCl.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos. 0562010,20962016)Ministry of National Education(No.203143)Program for New Century Excellent Talents in University
文摘A facile approach for the first synthesis of ocimarin, naturally occurring coumarins, was developed by employing a cerium (III) chloride heptahydrate-catalyzed Pechmann condensation of phenols and β-keto esters in a solvent-free system as key step, by which ocimarin was achieved by three steps starting from acetylacetic ether and resorcinol with total yield 23.2%. All structures of new compounds were confirmed by IR, ^1H NMR and MS.
基金supported by the National Natural Science Foundation of China(No.30873140)the Program for Excellent Talents of Beijing City(No.20071D0501600227)the Beijing Municipal Commission of Education(No.KM201010028011)~~
文摘The equilibrium solubility of CsCl CeCl 3 HCl(11%) H 2O quaternary system at 25 ℃ has been determined by the physic chemical analysis method, and the phase diagram was plotted. Two new double salts 3CsCl·CeCl 3·3H 2O and CsCl·CeCl 3·4H 2O obtained from the complicated system were identified and characterized by XRD, TG DTA, DSC, UV and fluorescence spectroscopy. Studies on the fluorescence excitation and emission show that 3CsCl·CeCl 3·3H 2O and CsCl·CeCl 3·4H 2O have upconversion luminescence of infrared visible range, and the upconversion emission intensity increases with the increase of ratio of CeCl 3 in CsCl.