Heterolytic Dihydrogen Activation by a Frustrated Carbene-Borane Lewis Pair

摘要

The Lewis acid-base concept is fundamental for the understanding and the prediction of chemical structure and reactivity. For instance, boranes (BR3) and phosphines (PR'3) represent prototypical Lewis acids and bases, respectively, and as such, they are prone to form stable donor-acceptor adducts in which the unshared pair of the base forms a covalent bond with the vacant orbital of the acid. Steric factors can suppress this inherent behavior, leading to so-called "frustrated Lewis pairs" (FLPs).