α-C-H Bond Functionalization of Unprotected Alicyclic Amines: Lewis-Acid-Promoted Addition of Enolates to Transient Imines

Enolizable cyclic imines, obtained in situ from their corresponding lithium amides by oxidation with simple ketone oxidants, are readily alkylated with a range of enolates to provide mono- and polycyclic beta-aminoketones in a single operation, including the natural product (+/-)-myrtine. Nitrile anions also serve as competent nucleophiles in these transformations, which are promoted by BF3 etherate. beta-Aminoesters derived from ester enolates can be converted to the corresponding beta-lactams.

Automated summary

Enolizable cyclic imines obtained in situ from lithium amides by oxidation with simple ketone oxidants can be readily alkylated with a range of enolates to provide mono- and polycyclic beta-aminoketones in a single operation, including the natural product (+/-)-myrtine. Nitrile anions also serve as competent nucleophiles in these transformations promoted by BF3 etherate. Moreover, beta-aminoesters derived from ester enolates can be converted to the corresponding beta-lactams.