CuCl‐Catalyzed Regio‐ and Stereoselective Aminohalogenation of α,β‐Unsaturated Nitriles
α,β-Unsaturated nitriles were found to be suitable substrates for aminochlorination with N,N-dichloro-p-toluenesulfonamide (4-TsNCl2) in the presence of CuCl as the catalyst (10 mol-%) and 4 A molecular sieves. The reaction is very convenient to carry out at room temperature without the protection of inert gases, and this method provides an easy route to vicinal haloamino nitriles with excellent regio- and stereoselectivities and in good chemical yields. The stereochemistry has been unambiguously confirmed by X-ray structural analysis. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)