Evaluation of Electron-Donor Properties of Amides and Lactams by ~(13)C NMR Spectroscopy

摘要

The relative basicity of a series of amides and latams was evaluated in the ~(13)C NMR scale by the change in the chemical shift of the carbonyl carbon siganl on deuteronation .The effect of the electronic structure of substituents n the electron-donor properties of the carbonyl oxygen atom was analyzed. The sterically strained ring in lactams and hydrocarbon substituents at the nitrogen atom increase the coutribution oft the N-deuteronated form to the acid-base equilibrium