Aminohalogenation of Electron-Deficient Olefins Promoted by Hypervalent Iodine Compounds

An efficient and practical procedure for the aminohalogenation of electron‐deficient olefins promoted by hypervalent iodine compounds has been demonstrated. The catalytic efficiency of various hypervalent iodine compounds with different carboxylic and sulfonic ligands has also been investigated and of these (diacetoxyiodo)benzene exhibited the highest activity. A series of substrates, including α,β‐unsaturated ketones, cinnamates, and cinnamides, were tolerable under the conditions employed and were aminochlorinated/‐brominated in good yields and with excellent diastereoselectivities.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) The aminochlorination and ‐bromination of electron‐deficient olefins in dichloromethane, mediated by hypervalent iodine compounds and utilizing Chloramine‐T trihydrate and a combination of TsNH2 and NBS as the nitrogen and bromine source, respectively, is reported.