Aziridination of alkenes proceeds successfully using Chloramine-T (N-chloro-N-sodio-p-toluenesulfonamide). When anhydrous Chloramine-T was added to an acetonitrile solution of alkenes in the presence of various CuCl catalysts and MS-5A, the corresponding aziridines were obtained in moderate to good yields. (C) 1997 Elsevier Science Ltd. All rights reserved.