title: Catalytic, asymmetric Mannich-type reactions of alpha-imino esters bearing readily removable substituents on nitrogen.
abstract: [reaction: see text] Catalytic, enantioselective Mannich-type reactions of alpha-imino esters bearing readily removable substituents on nitrogen are described. Several N-carbamate-protected alpha-imino esters, which are readily prepared from 2-bromoglycine esters using a polymer-supported amine, reacted with silicon enolates to afford the desired adducts in high yields with high enantioselectivity using a copper(II)-diamine complex. Easy deprotection of the product amine and transformation to free alpha-amino acid derivatives have also been demonstrated.
authors.affiliation: Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Matsubara
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kiyohara
authors.forename: Shū
authors.initials: S
authors.lastname: Kobayashi