In summary, the high Lewis acidity of bis(1-methyl-orthocarboranyl)borane (HBo Me Cb2) is leveraged for the uncatalyzed dearomative C2-borylation of indoles. Borane screening revealed that both sterics and Lewis acidity are essential with HBo Me Cb2 performing better than fluoroaryl boranes. Despite the hydride on boron, no hydroboration reactivity was observed for any substrates. Substrate screening indicated that substitution on the 6-membered ring is well tolerated but bulky groups on nitrogen or a methyl on C3 position inhibit the reaction. The parent indole undergoes N-borylation rather than C2-borylation. In all reactions mild conditions are used and atom economy is preserved. This work demonstrates the potential of HBo Me Cb2 as a borylation reagent that will continue to be investigated.