A rigid redox-active-ligand-supported bis(germylene) as a two-centre six-electron donor.

A naphthyridine diimine (NDI) supported bis(germylene) NDI-Ge containing two dicoordinate, coplanar Ge(II) atoms has been synthesised. Computational investigations on NDI-Ge indicated the two Ge(II) atoms are nearly independent. The EDA-NOCV analysis of the [NDI-Ge][Fe(CO)] complex revealed the six-electron donor behavior of NDI-Ge, the first example for group-14-element-based bidentate ligands.