A Non-innocent Ligand Supported Germylene and Its Diverse Reactions

Abstract

To expand the reactivity scope of divalent germanium, an α-iminopyridine supported dicoordinate germanium complex (2) was prepared from deamination of the corresponding pyridine-coordinated diamido germylene (1). The non-innocent ligand supported germanium compound can be viewed as a benzo-fused N-heterocyclic germylene or a neutral α-iminopyridine-coordinated germylone. While the Ge-ligand cooperation observed in the reaction of 2 with HCl and BCl3 confirms the presence of a vacant p orbital at the Ge(II) atom, the readily transferring of a ligand from 2 to MCl2 (M = Ge, Sn) with the extrusion of metallic germanium reflects the electron richness of the central Ge(0) atom. The germylone character of 2 was further verified via four-electron oxidation with 2 equiv of tetra-chloro-o-benzoquinone to give the corresponding six-coordinated germanium(IV) adduct.