Regio‐ and Stereoselective Copper‐Catalyzed Synthesis of Vicinal Haloamino Ketones from α,β‐Unsaturated Ketones

Abstract

Abstract The regio‐ and stereoselective aminochlorination of α,β‐unsaturated ketones has been developed. The reaction was conducted with N , N ‐dichloro‐ p ‐toluenesulfonamide (4‐TsNCl 2 ) as the nitrogen/halogen source and CuOTf as the catalyst, at 0 °C to room temperature. This method provides an easy access to vicinal haloamino ketones, with excellent regioselectivity and up to quantitative yields. Both aromatic and aliphatic enones react well with 4‐TsNCl 2 under the present system, but give opposite regioselectivity. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)