Dynamic kinetic asymmetric transformations of β-halo-α-keto esters by N,N′-dioxide/Ni(ii)-catalyzed carbonyl-ene reaction

Abstract

Dynamic kinetic asymmetric transformations of racemic β-halo-α-keto esters through carbonyl-ene reaction were realized using a chiral N,N′-dioxide-nickel(II) complex, giving the corresponding β-halo-α-hydroxy esters containing two vicinal chiral tri- and tetrasubstituted carbon centers in good yields and dr with excellent ee values without the use of extra bases. Meanwhile, a proposed reaction mechanism was presented according to the configuration of the product.