Dimere Alkalimetallbenzamidinate: Einfluß des Metallions auf die Struktur

The molecular structures of two N-silylated alkali metal benzamidinates, [MeC6H4C(NSiMe3)2-Li(THF)]2 1 and [PhC(NSiMe3)2Na(Et2O)]2·Et2O 2, have been determined by low temperature X-ray diffraction studies. Both compounds are dimeric in the solid state but the molecular structures are strongly influenced by the alkali metal used. The Na---Na distance in 2 is unusually short (274.1 pm). The preparation of K[PhC(NSiMe3)2] (3) is also described.