Syntheses and Crystal Structures of Heteroleptic Stannylenes and Germylenes

Abstract

Two novel, monomeric heteroleptic derivatives of divalent Sn [Sn(2-{(Me3Si)2C}-C5H4N)R] [R = Sn(SiMe3)3 (1) or Si(SiMe3)3 (2)] and divalent Ge [Ge(2-{(Me3Si)2C}-C5H4N)R] [R = Cl (3) or CH(PPh2)2 (4)] have been prepared and characterized, and their molecular structures were determined by single-crystal X-ray diffraction. The stannylenes 1 and 2 were prepared from the corresponding heteroleptic chloro-analogue, [Sn(2-{(Me3Si)2C}-C5H4N)Cl]; 1 is the first structurally characterized compound to contain a bond between divalent Sn and tetravalent Sn and 2 is only the second structurally characterized example of a silyl-substituted heteroleptic stannylene. The Ge analogue of [Sn(2-{(Me3Si)2C}-C5H4N)Cl] (3) has been prepared and its utility as a precursor to further examples of heteroleptic germylenes demonstrated by the preparation and characterization of [Ge(2-{(Me3Si)2C}-C5H4N)CH(PPh2)2] (4).