Synthesis and Structure of Hypervalent Diacetoxybromobenzene and Aziridination of Olefins with Imino-λ3-bromane Generated in Situ under Metal-Free Conditions

Ligand exchange of p-CF3C6H4BrF2 with acetoxy groups using AcOH and Ac2O affords (diacetoxybromo)benzene in a high yield, which undergoes aziridination of alkenes in the presence of TfNH2 and sulfamate esters in one pot under mild conditions. The aziridination with TfNH2 proceeds stereospecifically with retention of stereochemistry of olefins at room temperature using limiting amounts of olefins under transition-metal-free conditions. The one-pot aziridination procedure using sulfamate esters can be applied to the intramolecular versions.