A Barium Complex of the Silanide SiH3-: Hydride Surrogate and Source of Silicon.

Abstract

The silanide SiH3- is an archetypical anion. Its metathesis chemistry is, however, still underdeveloped. We have conveniently prepared the barium silanide complex [(dtbpCbz)BaSiH3]8 with a bulky carbazolide ligand by reaction of the corresponding barium amide with phenyl silane in a good yield. The silanide complex was then used in various metathesis reactions, displaying distinct reactivity toward different substrates. Toward organic substrates such as carbodiimide or benzophenone, the silanide acted as a hydride surrogate, and formamidinate or diphenylmethoxide ligands were formed. Toward the monocoordinated cation [(dtbpCbz)Ge]+, transfer of SiH3- was observed, and the decomposition of the silylgermylene [(dtbpCbz)GeSiH3] was studied. For the heavier, more easily reducible congeners [(dtbpCbz)Sn]+ and [(dtbpCbz)Pb]+ as substrates, [(dtbpCbz)SiH3] was obtained under elimination of elemental Sn and Pb, so that formally SiH3+ was transferred to the dtbpCbz- ligand.