Catalytic Enantioselective Hosomi–Sakurai Reaction of α-Ketoesters Promoted by Chiral Copper(II) Complexes

Yutaro Niwa, Mayu Miyake, Ichiro Hayakawa, Akira Sakakura* 
Chem. Commun.2019, 55 (27), 3923–3926.  (Published online: March  5, 2019) 
DOI: 10.1039/C9CC01159E 

A catalytic enantioselective Hosomi–Sakurai reaction of α-ketoesters has been developed.  A copper(II) complex with a chiral bis(oxazoline) ligand bearing methanesulfonamide groups shows excellent catalytic activity to give α,α-disubstituted α-hydroxyesters in high yields with high enantioselectivities.  This is the first successful method for the catalytic enantioselective 1,2-addition of α-ketoesters with allylic silanes.