• 研究论文 •

### 布洛芬分子手性转变裸反应机理及水分子的催化作用 ——基于羰基和苯环作H迁移桥梁

1. 1.白城师范学院物理学院，吉林 白城 137000；
2.白城师范学院计算机科学学院，吉林 白城 137000
• 收稿日期:2016-05-09 出版日期:2016-11-25 发布日期:2016-11-25
• 通讯作者: 通讯作者：王佐成;E-mail:wangzc188@163.com

### Bare reaction mechanism of chiral transition of ibuprofen molecules and the catalysis of water molecules using carbonyl and benzene ring as H transfer bridge

GAO Feng1, WANG Zuocheng1,YAN Hongyan2,YANG Xiaocui1, TONG Hua1

1. 1. The college of Physics, Baicheng Normal College, Baicheng 137000, China;
2.Computer Science Department, Baicheng Normal College, Baicheng 137000, China
• Received:2016-05-09 Online:2016-11-25 Published:2016-11-25

Abstract:

The bare reaction of chiral transition of ibuprofen molecules and the mechanism of waterassisted proton transfer from carbon to carbonyl were studied using the B3LYP method of density functional theory and the MP2 method of perturbation theory. The molecular structure analysis showed that the hydrogen bond angles corresponding to the eight membered ring transition state bTS2·2H2O, and the ten membered ring transition state bTS2·3H2O in the processes of water-assisted proton transfer from carbon to carbonyl were all much larger than that corresponding to the six membered ring transition state bTS2·1H2O. Moreover the eight membered ring structure of transition state bTS2·2H2O was almost coplanar, and the ten membered ring structure of transition state a_TS1·3H2O/bTS2·3H2O was obviously out of plane. The study on the reaction path showed that there were six paths in the title reaction, where respectively proton only using ketonic O or methyl C and carbonyl O or carbonyl and benzene ring as the transfer bridge from one side to the other of chiral C. Calculations of potential energy surface showed that the path using proton was the dominant reaction channel, and carbonyl and benzene ring as the transfer bridge was the dominant reaction path. The Gibbs free energy barrier of the rate-determining step of bare reaction was 287.1 kJ·mol-1, which would be reduced to 144.9 kJ·mol-1 because of the chains constituted by two water molecules. The results showed that the chiral transition of ibuprofen molecules could be realized in multiple paths and the water molecules had a better catalysis on H transfer heterogeneous reaction of ibuprofen molecules, as well as the presence of water molecules in the body of a life, temperature fluctuations, molecular frequent collisions and the action of some enzyme conditions were the cause of S-Ibu optical isomers.