Reactivity Trends in Reactions between Nucleophiles and Electrophiles

4 Reactivity Trends in Reactions between Nucleophiles and Electrophiles 

As noted above, the mechanism of reactions between nucleophiles and electrophiles may be viewed as an electron transfer from the nucleophile to the electrophile, and a coupling of the supplementary electron of the electrophile to the remaining electron of the nucleophile. The corresponding promotion energy G is the vertical electron-transfer energy from the nucleophile to the electrophile (see, Eq. 6.8 and Section 6.4.2). 

FIGURE 6.9 The ground and vertical charge-transfer states in the VBSCD that describes a nucleophilic attack on a carbonyl group. 

FIGURE 6.10 A plot of the free energy of activation for nucleophilic cleavage of an ester versus the vertical ionization potential of the nucleophile. (Adapted with permission from Ref. 39.) 

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