title: Highly homogeneous stereocontrolled construction of quaternary hydroxyesters by addition of dimethylzinc to α-ketoesters promoted by chiral perhydrobenzoxazines and B(OEt)3.
abstract: A highly efficient enantioselective addition of Me(2)Zn to α-ketoesters, assisted by a chiral perhydro-1,3-benzoxazine ligand, is described. This novel catalytic system offers homogeneous elevated enantioselectivities in the preparation of α-hydroxyesters that bear a quaternary stereocenter, with a minor dependence on electronic and steric effects when aromatic, heteroaromatic, or aliphatic α-ketoesters are employed. The catalyst can be recovered and reused without loss of activity.
authors.affiliation: Centro de Innovación en Química y Materiales Avanzados (CINQUIMA) and Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain.
authors.forename: Rebeca
authors.initials: R
authors.lastname: Infante
authors.forename: Javier
authors.initials: J
authors.lastname: Nieto
authors.forename: Celia
authors.initials: C
authors.lastname: Andrés