Density Functional Theory Studies on the Mechanisms of Regioselective Allylic and cis-Vinylic Deprotonation of Allyl Amides and Allylamines

A density functional theory (B3LYP/6-31+G*) study was undertaken in an effort to learn more about the mechanisms controlling the regioselective deprotonations of the synthetically versatile N-lithio-N-(tert-butyl)allylamide 1 and N-lithio-N-(trimethylsilyl)allylamine 2 compounds. The calculations suggest that deprotonation of 1 occurs exclusively at the allylic position. This agrees with experimental results. The calculations also suggest that deprotonation of allylamine 2 exclusively at the cis-vinylic position is due to kinetic control.