Nucleophilic Reactivities of Schiff Bases

Dedicated to Professor Heinrich Nöth on the occasion of his 85th birthday The nucleophile-specific parameters N and sN, as defined by the linear free energy relationship log k = sN(N +E) (J. Am. Chem. Soc. 2001, 123, 9500 – 9512), were determined for five imines 1a–e by studying the kinetics of their reactions with benzhydrylium ions in dichloromethane solution at 20 ◦C. These parameters allowed us to include representative Schiff bases into our comprehensive nucleophilicity scale and compare their reactivities with those of other N-nucleophiles.