摘要
采用色散校正密度泛函的ωB97X-D方法、微扰理论的MP2方法和自洽反应场的SMD模型方法,研究了Asp分子2种稳定构象(Asp_1和Asp_2)的标题反应。反应通道与势能面的研究发现:Asp分子经过氢氧根(水分子簇)和α-碳抽氢及α-羧羟基、β-羧羟基、β-羧基和R-基旋转的一系列过渡态,实现了手性对映体转变。氢氧根抽α-氢和α-碳抽水分子的氢致Asp_1和Asp_2旋光异构的决速步内禀能垒在27.0 kJ/mol左右;水分子辅助氢氧根离子抽α-氢和α-碳抽2个水分子簇的氢致Asp_1和Asp_2旋光异构的决速步内禀能垒分别是34.0和40.0 kJ/mol左右。质子攻击中间体碳负离子的α-碳会加快Asp手性转变的进程。
Using the dispersion correction density functionalωB97X-D method,the MP2 method of perturbation theory and the SMD model method of self-consistent reaction field,the title reaction of two stable conformations(Asp_1 and Asp_2)of Asp was investigated.The study of reaction channel and potential energy surface showed that the chiral enantiomer transition was realized by a series of Asp transition states of H-atom abstraction of hydroxyl ion(water clusters)andα-carbon,as well as the rotation ofα-carboxy hydroxyl,β-carboxy hydroxyl,β-carboxyl and R-group.The intrinsic energy barrier of the rate-determining step of optical isomerization of Asp_1 and Asp_2 induced byα-H abstraction of hydroxyl ion and H abstraction of water molecule ofα-carbon was about 27.0 kJ/mol,and the corresponding intrinsic energy barriers induced by H-atom abstraction of hydroxyl ion assisted with water molecule and H-atom abstraction of two water molecule ofα-carbon were about 34.0 and 40.0 kJ/mol,respectively.It could accelerate the process of Asp chiral transition that proton attacks theα-carbon of intermediate carbon anion.
作者
乔朝阳
闫红彦
孙永清
刘一司
吕路瑶
佟华
王佐成
QIAO Chaoyang;YAN Hongyan;SUN Yongqing;LIU Yisi;LV Luyao;TONG Hua;WANG Zuocheng(Computer Science College,Baicheng Normal University,Baicheng 137000,China;Department of Basic,Baicheng Technician Institute,Baicheng 137000,China;College of Physics,Baicheng Normal University,Baicheng 137000,China)
出处
《中山大学学报（自然科学版）》
CAS
CSCD
北大核心
2020年第1期144-153,共10页
Acta Scientiarum Naturalium Universitatis Sunyatseni
基金
吉林省科技发展计划自然科学基金(20130101308JC)
吉林省大学生创新项目(2019056)
关键词
手性对映体
天冬氨酸
氢氧根
水分子
密度泛函理论
微扰理论
SMD模型
能垒
chiral enantiomer
aspartic
hydroxyl
water molecule
density functional theory
perturbation theory
SMD model
energy barrier
