The concept of boranes as ligands

摘要

The idea that electron deficient boranes can act as novel electron-donor ligands has proved to be remarkably productive in developing new and unusual aspects of the chemistry of the boron hydrides. Polyhedral boranes and their anions have fewer valence electrons than orbitals available for bonding and are, therefore, normally classified as electron deficient species. However, many can act as excellent polyhapto ligands to form a variety of coordination complexes that are often more stable than the parent boranes themselves. Indeed, many of the binary boranes and their anions can themselves usefully be regarded as coordination complexes of a borane donor and a borane acceptor, i.e. a borane-borane adduct.