N-Aryl/Heteroaryl Oxaziridines: From Photochemical Synthesis to Reactivity Investigation in Heteroatom Transfer Reactions

The reactivity of oxaziridines is significantly influenced by the substituents on the nitrogen atom. Despite extensive studies since their discovery by Emmons in 1956, research on the reactivity of N-aryl/heteroaryl oxaziridines remains limited. This limitation is likely due to the lack of efficient synthetic methods. In this study, a visible -light-induced photochemical strategy was developed to address this challenge. First, a series of stable biaryl-substituted N-heteroaryl oxaziridines were synthesized and isolated via the photochemical reaction of aryl/aryl diazoalkanes with nitrosoarenes. Further studies showed that some unstable N-aryl/heteroaryl oxaziridines, generated in-situ from the photochemical rearrangement of nitrones, show remarkable heteroatom transfer reactivities. These oxaziridines can act as both oxygen and nitrogen atom transfer reagents, depending on the nucleophiles involved. Moreover, the synthetic potential of this method was further highlighted through the successful modification of complex natural products and pharmaceutical derivatives. This study provides valuable insights into the synthesis and application of N-aryl/heteroaryl oxaziridines, thereby enhancing their utility in synthetic chemistry.