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.