Hypoiodite-Mediated Metal^Free Catalytic Aziridination of Alkenes

摘要

Aziridination of alkenes is an important chemical transformation and is a convenient method for accessing various nitrogen-containing products and synthetic intermediates. Particularly useful aziridinating reagents are N-tosyliminoio-danes (ArlNTs), which are important representatives of the rapidly growing field of hypervalent-iodine reagents. Numerous synthetically useful aziridination methods are based on the use of metal salts or complexes as catalysts (for example, derivatives of Cu, Mn, Fe, and Rh) and ArlNTs as nitrenium precursors.However, from both environmental and economical viewpoints, avoiding toxic metals and performing reactions under metal-free conditions, is critically important in the development of "green" synthetic methodologies. Recently, the research groups of Che and Yudin reported metal-free conditions for aziridination using (diacetoxyiodo)benzene and N-aminoheterocycles. Che and co-workers have also reported aziridination using in situ generated hypervalent-iodine reactive species, However the attempted realization of the catalytic version of aziridination was not successful. Likewise, Wirth and co-workers were unsuccessful in their broad search for reaction conditions to effect organocatalytic alkene aziridination using N-aminophthalimide (PhthNH2) as the nitrenium source.To the best of our knowledge, the organocatalytic aziridination of alkenes using PhthNH2 as the nitrenium precursor has not yet been developed.