取代苯甲酸、取代苯酚酸性PKa和取代苯胺碱性PKb的分子拓扑研究

基于元素的Pauling电负性,原子成σ键的电子数,原子直接键连的氢原子数目和原子形成离域键时所提供的PZ电子数,建立了一种分子连接性指数(4X),它与19种取代苯酚酸性Pka的线性方程为:Pka=14.1127-1.63754X,它与22种取代苯胺碱性Pkb的线性方程为:Pkb=4.5524 2.08464X.它与30种取代苯甲酸酸性Pka的线性方程为:Pka=7.1000-0.72034X.结果表明,4X具有良好的结构选择性和性质相关性,可用于预测其它取代苯甲酸、取代苯酚酸性Pka值和取代苯胺碱性Pkb值.

Molecular topological research on the PKa values for substituted benzene carbonic acids and substituted phenols, and the PKb values for substituted phenylamines

On the elemental electronegative,bondid electron number and PZ electron number of atoms,one new molecular topological index(4 X)is developed for research on the PKa values for 19 substituted phenols and 30 substitnted benzene carbonic acids,and the PKb values for 22 substituted phenylamines in this paper.With it,the linear relationship between the PKa values of substituted phenols and the molecular topological index(4 X)are obtained,ie.PKa=14.1127-1.6375 4 X,r=-0.9649;the linear relationship between the PKb values of substituted benzenne and the molecular topological index(4X) are obtained,i.e.PKb=4.5524 2.08464 X,r=0.9589.It is concluded that the indexes have good structure selectivity and property relativity.It can be extended to predict the PKa values of other substituted phenols and the PKb values of other substituted benzenne amines.