(PNSiMe3)4(NMe)6: A robust tetravalent phosphaza-adamantane scaffold for molecular and macromolecular chemistry

Tetraarylmethanes and adamantanes are very rare examples of rigid, four-way, anionic connectors that play a scaffolding role in multiple areas of molecular and materials chemistry. We report the synthesis of a tetravalent phosphaza-adamantane cage, (PNSiMe3)4(NMe)6 (2), that shows unusually high ambient, thermal, and redox stability due to its unique geometry. It nevertheless participates in four-fold functionalization reactions on its periphery. The combination of a robust core but a reactive corona makes 2 a convenient inorganic scaffold upon which tetrahedral molecular and macromolecular chemistry can be reliably constructed. This potential is exemplified by the unprecedented synthesis of a tetracationic tetraphosphinimine (3) and the first porous all-P/N polyphosphazene network (5).