A comparison between theoretical and experimental models of electrophilicity and nucleophilicity

Four different theoretical models of electrophilicity and nucleophilicity has been discussed in the light of experimental available evidence for a series of 20 benzhydrylium ions taken as reference electrophilic systems and 16 primary and secondary amines as nucleophilic systems. It is shown that the theoretical scales are linearly related to the well-known experimental ones based on the electrophilicity (E) and nucleophilicity (N and s) parameters derived by Mayr from the rate constants k20 °C associated to general electrophile-nucleophile combinations, log k20 °C = s(N + E).