Compounds of Germanium and Tin, 2l. A Tetraaryldigermene with a Short Germanium‐Germanium Double Bond and a Nearly Planar Environment of Both Germanium Atoms

Abstract

AbstractTreatment of GeCl2 · dioxane with the Grignard reagent RMgBr (R=2‐tBu‐4,5,6‐Me3C6H) furnishes the tetraaryldigermene R2GeGeR2 (8). X‐ray structure‐analysis of 8 reveals a short GeGe double bond, a nearly planar environment of both germanium atoms and extremely widened CGeC angles of 128°. In solution, 8 dissociates into two germylene molecules R2Ge, which can be trapped with oxygen or by [4+1] cycloaddition reactions with 1,4‐dihetero‐1,3‐dienes. A similar cycloadduct of a stannylene wa obtained by thermolysis of (R′2Sn)3 (R′=2,4,6‐iPr3C6H2), in the presence of a 1,4‐diazabutadiene and characterized by an X‐ray structure‐analysis.