Copper-catalyzed trifluoromethylation of alkenes: synthesis of trifluoromethylated benzoxazines

A simple base and ligand free copper catalyzed method for the construction of trifluoromethylated benzoxazines has been developed by using Umemoto's reagent. It involves the oxidative difunctionalization of alkenes through tandem C-O and C-CF3 bond formations. Furthermore, synthesized benzoxazines were selectively converted into trifluoromethylated allylic and (E)-vinylic benzamides by the treatment of (KOBu)-Bu-t and CH3Li, respectively.