Ring Expansion of Donor-Acceptor Cyclopropane via Substituent Controlled Selective N-Transfer of Oxaziridine: Synthetic and Mechanistic Insights

Abstract

A distinctive N -substituent controlled electrophilic N -transfer of oxaziridines with donor − acceptor cyclopropanes in the presence of MgI 2 is reported. Contrary to earlier reports, the oxaziridine having bulkier N - substituents can also give N -transferred product instead of the O -transferred one. Interestingly, the oxaziridines having α -H containing N -substituents lead to the pyrrolidine derivatives through [3 + 2] cycloaddition. A mechanistic reasoning for this divergent reactivity is depicted by density functional theory calculations and validated through energy decomposition analysis.