Morpholine Ketene Aminal as Amide Enolate Surrogate in Iridium-Catalyzed Asymmetric Allylic Alkylation

摘要

Morpholine ketene aminal is employed in iridium-catalyzed asymmetric allylic alkylation reactions as a surrogate for amide enolates to prepare gamma,delta-unsaturated beta-substituted morpholine amides. Kinetic resolution or, alternatively, stereospecific substitution affords the corresponding products in high enantiomeric excess. The utility of the products generated by this method has been showcased by their further elaboration into amines, ketones, or acyl silanes. A putative catalytic intermediate (eta(3)-allyl)iridium(III) with achiral P,Olefin-ligand was synthetized and characterized for the first time.