Iron-Catalyzed, Directed Benzylic Borylation

Herein, we describe an iron-catalyzed benzylic C–H borylation reaction. The reaction targets primary and secondary C(sp3)–H bonds to deliver high-value boronic esters under mild conditions with short (7–8 min) reaction times. Functional groups are well tolerated, and complete site selectivity is observed in the presence of multiple benzylic C–H bonds.