Conjugated imines and iminium salts as versatile acceptors of nucleophiles
作者:Makoto Shimizu、Iwao Hachiya、Isao Mizota
DOI:10.1039/b814930e
日期:——
development of synthetic methodologies where nucleophilicaddition reactions to imino carbons are utilized in crucial steps. This article summarizes double nucleophilicaddition reactions with alpha,beta-unsaturated aldimines, addition reactions using alkynyl imines, "umpoled" reactions of alpha-imino esters, and the use of iminium salts as reactive electrophiles.
A New Synthetic Method for α-Alkoxycarbonyl Iminium Salt and Its Reaction with Nucleophiles
作者:Makoto Shimizu、Hiroyuki Itou、Megumi Miura
DOI:10.1021/ja042330f
日期:2005.3.1
An iminium salt was easily prepared using the oxidation of amino ketene silyl acetal with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, and the subsequent nucleophilic addition to this iminium species proceeded efficiently to afford alpha-amino esters in good yields.
Role reversal: The title reaction has been developed to deliver α‐amino acids under very mild reaction conditions (see scheme; dpppen=1,5‐bis(diphenylphosphino)pentane). The catalysis provides a new CN bond‐forming approach for the synthesis of α‐amino acids by using an umpolung, electrophilic amination strategy.