ee的英文名称就Enantionmeric excesses 对映体过量 ee=([R]-[S]/[R]+[S])*100%，通常用来表征单手性光学纯度的！
d.e.的英文名称是Diastereomeric excesses 非对映体过量，通常用来表征两个以上手性中心时的光学纯度，d.e.=([RR]-[SR]/[RR]+[SR])*100%！！

一篇专门介绍ee值和de值2006年JOC文献

J. Org. Chem. 2006, 71, 2411-2416

Do the Terms “% ee” and “% de” Make Sense as Expressions of
Stereoisomer Composition or Stereoselectivity?

Enantiomeric excess (ee) was originally defined as a term to describe enantiomeric composition and was equated with optical purity. More recently, ee and its cousin de (diastereomeric excess) have been used
(inappropriately) to quantitate stereoselectivity. The quantity ee has been used in equations describing processes such as kinetic resolutions, but these equations are unnecessarily complex because it is enantiomer ratio, not enantiomeric excess, that directly reflects relative rates. A historical summary of the development of ee as an expression of enantiomer composition and enantioselectivity is presented, along with new equations and figures defining and illustrating the stereoselectivity factor, s, kinetic resolutions versus % conversion, and linear correlations of enantiomer composition of catalysts and products. New figures illustrating nonlinear effects versus enaniomer composition are presented, and Kagan’s index of amplification for positive nonlinear effects is discussed and illustrated. A case is made for the
discontinuance of ee and de as descriptors of stereoisomer composition and stereoselectivity，

二楼给的那片文献非常全面系统的讲解了ee,de,er,dr等不对称合成里面经常用到的表征值。
对于具体到某一个不对称合成来说，如果产物只有一个手性中心，在用高效液相量化其对映选择性的时候，如果不是100％光学纯，则会出现两个对映异构体的峰，峰面积的比值是er,即 enantiomeric ratio. 两个峰面积的差值就是ee值，即enantiomeric excess.如果产物有两个或者两个以上的手性中心（一般是两个，再多就太复杂了），峰面积的比值是diastereomeric ratio,两个异构体的差值则是diastereomeric excess。
其实

哦。。。。原来如此
谢谢楼上的两位！

二楼的佩服亚！！！

dingding, good ,thanks

xiexie  2 3 lou