Bis(1‐Methyl‐ortho‐Carboranyl)Borane

Abstract The Lewis superacid, bis(1‐methyl‐ ortho ‐carboranyl)borane, is rapidly accessed in two steps. It is a very effective hydroboration reagent capable of B−H addition to alkenes, alkynes, and cyclopropanes. To date, this is the first identified Lewis superacidic secondary borane and most reactive neutral hydroboration reagent.