Regio‐ and Stereoselective Synthesis of anti‐1,3‐Diaryl‐3‐chloro‐ 2‐(o‐nitrophenylsulfonylamino)‐3‐propan‐1‐ones through Catalytic Aminohalogenation Reaction of α,β‐Unsaturated Ketones

The synthesis of anti‐1,3‐diaryl‐3‐chloro‐2‐(2‐nitrophenylsulfonylamino)‐3‐propan‐1‐ones has been achieved. The aminohalogenation of α,β‐unsaturated ketones resulted in the vicinal haloamine products in high regio‐ and stereoselectivity and modest to good chemical yields. The reaction can be conducted under convenient conditions by using the combination of 2‐NsNCl2/2‐NsNHNa (2‐Ns = 2‐nosyl = 2‐nitrophenylsulfonyl) as the nitrogen/chlorine source and by using copper(I) triflate as the catalyst. An N‐(2‐nosyl)‐N‐H‐aziridinium intermediate was proposed to exist in the aminohalogenation process. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)