Direct and Stereospecific Synthesis of N-H and N-Alkyl Aziridines from Unactivated Olefins Using Hydroxylamine-O-Sulfonic Acids

A Rh^II-catalyzed direct and stereospecific N-H- and N-alkyl aziridination of olefins is reported that uses hydroxylamine-O-sulfonic acids as inexpensive, readily available, and nitro group-free aminating reagents. Unactivated olefins, featuring a wide range of functional groups, are converted into the corresponding N-H or N-alkyl aziridines in good to excellent yields. This operationally simple, scalable transformation proceeds efficiently at ambient temperature and is tolerant towards oxygen and trace moisture.