Transition-metal-free C-H oxidative activation: persulfate-promoted selective benzylic mono- and difluorination

An operationally simple and selective method for the direct conversion of benzylic C-H to C-F to obtain mono-and difluoromethylated arenes using Selectfluor (TM) as a fluorine source is developed. Persulfate can be used to selectively activate benzylic hydrogen atoms toward C-F bond formation without the aid of transition metal catalysts.