Coupling of arylboronic acids with benzyl halides or mesylates without adding transition metal catalysts

We report herein a transition-metal-free coupling reaction of arylboronic acids with benzyl halides and mesylates for the construction of C(sp2)C(sp3) bonds. A unique feature of this coupling reaction is the formation regioisomers in some cases. Mechanistic studies suggest that this reaction may proceed via an unprecedented Friedel-Crafts-type reaction pathway under base conditions with the assistance of boronic acid moiety.