Effect of structure on the kinetics of the nucleophilic substitution of acylonium ions

A study was carried out on 67 reactions involving transfer of acyl groups from the corresponding N-, O-acylonium salts to pyridine N-oxides, highly basic pyridines, and N-methylimidazole in acetonitrile solution. PM3 calculations were carried out for the ionization potentials of the nucleophiles and electron affinities of the N-, O-acylonium cations. A multiparameter correlation was obtained predicting the rate of acyl group transfer.