Cobalt‐Catalyzed Asymmetric Aza‐Nozaki–Hiyama–Kishi (NHK) Reaction of α‐Imino Esters with Alkenyl Halides

Abstract

AbstractChromium‐catalyzed enantioselective Nozaki–Hiyama–Kishi (NHK) reaction represents one of the most powerful approaches for the formation of chiral carbon‐heteroatom bond. However, the construction of sterically encumbered tetrasubstituted stereocenter through NHK reaction still posts a significant challenge. Herein, we disclose a cobalt‐catalyzed aza‐NHK reaction of ketimine with alkenyl halide to provide a convenient synthetic approach for the manufacture of enantioenriched tetrasubstituted α‐vinylic amino acid. This protocol exhibits excellent functional group tolerance with excellent 99 % ee in most cases. Additionally, this asymmetric reductive method is also applicable to the aldimine to access the trisubstituted stereogenic centers.