Friedel–Crafts benzylation of arenes with benzyl fluorides using 9-borabicyclo[3.3.l]nonane (9-BBN) as a mediator has been developed. This provides a simple and cheap route to the activation of C–F bonds to synthesize 1,1-diarylmethanes in good to excellent yields (up to 98%) under mild conditions. Functional group tolerance and the mechanism are considered.