Density functional theory studies on the mechanism of the synthesis propylene carbonate by CO2 catalyzed proline ionic liquids
XU Lian-cai
ZHANG Zhi-qiang
PENG Qiong-yang
MAO Ming
SHAO Chen
JIANG Ling
WANG Guo-qing
Abstract：The possible reaction paths of synthesis of propylene carbonate catalyzed by proline ionic liquid were studied by density functional theory (DFT).The geometries of reactants,transition states and products were optimized at M06 /6-31 +G(d)theoretical level.All stationary point and transition states were verified accord-ing to the number of imaginary frequency through harmonic vibrational analysis,transition states were also con-firmed by intrinsic reaction coordinate analysis.Single point energy for each species was recalculated at M06 /6-311 ++G(2d,p)theoretical level.The results indicated that 2,4-pentanedione was activated by proline an-ion through a proton transfer reaction to yield 2,4-pentanedione anion which contained a carbon anion.The synthesis of propylene carbonate was catalyzed by the 2,4-pentanedione anion.Alternatively,the 2,4-pentane-dione anion was able to be carboxylated by CO2 .The carboxylated 2,4-pentanedione anion showed a higher catalytic activity,however,the carboxylation reaction was a thermodynamic unfavorable process.
Keywords：density functional theo-ryproline ionic liq-uidsCO2 catalyticpro-pylene carbonate
Publication Date：2016-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 89-95 )