Two Different Pathways of Stereoinformation Transfer: Asymmetric Substitutions in the (−)-Sparteine Mediated Reactions of Laterally Lithiated N,N - Diisopropyl- o -ethylbenzamide and N -Pivaloyl- o -ethylaniline

Highly enantioenriched substitution products can be obtained by the (−)-sparteine mediated lithiation−substitution reactions of the laterally lithiated intermediates 3·1 and 14·1 derived from the amides 2 and 13 . Either enantiomer of the products can be obtained with high enantioenrichment using (−)-sparteine as the ligand by appropriate choice of the protocol. The enantiodetermining step in both sequences occurs after deprotonation. Enantioenrichment in the sequence with 3·1 arises from a dynamic kinetic resolution, whereas enantioenrichment in the sequence with 14·1 arises from a dynamic thermodynamic resolution.