Highly efficient catalytic chloroamination reaction of alpha,beta-unsaturated gamma-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 gamma-carbonyl-beta-chloro-alpha-amino acid derivatives and alpha-chloro-beta-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.