title: Catalytic asymmetric chloroamination reaction of α,β-unsaturated γ-keto esters and chalcones.
abstract: Highly efficient catalytic chloroamination reaction of α,β-unsaturated γ-keto esters and chalcones has been developed via a chloronium-based mechanism to deliver anti-regioselective vicinal chloroamines instead of the aziridinium intermediates delivered aminochlorides. The combination of TsNCl(2) and TsNH(2) as reagents made the transformation highly efficient, delivering the γ-carbonyl-β-chloro-α-amino acid derivatives and α-chloro-β-amino-ketone derivatives in nearly quantitative yields with up to 99% ee and 99:1 dr under 0.05-0.5 mol % catalyst loading. TsNHCl was demonstrated to act as the key reactive species to form a bridged chloronium ion intermediate in the presence of a chiral scandium complex. The method might provide useful information for further realization of other haloamination reactions.
authors: Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, PR China.
authors: Yunfei
authors: Y
authors: Cai
authors: Xiaohua
authors: X
authors: Liu
authors: Jun
authors: J
authors: Jiang
authors: Weiliang
authors: W
authors: Chen
authors: Lili
authors: L
authors: Lin
authors: Xiaoming
authors: X
authors: Feng