Ge(0) Compound Stabilized by a Diimino-Carbene Ligand: Synthesis and Ambiphilic Reactivity

Area of Science:

• Organometallic Chemistry
• Inorganic Chemistry
• Carbene Chemistry

Background:

• N-heterocyclic carbenes (NHCs) are versatile ligands in organometallic chemistry.
• Germanium-based compounds are less explored compared to other group 14 elements.

Purpose of the Study:

• To synthesize and characterize a novel germylone featuring a diimino N-heterocyclic carbene ligand.
• To investigate the reactivity and structural properties of the synthesized germylone.

Main Methods:

• Synthesis via reduction of a germanium cation using KC8.
• Structural characterization using NMR spectroscopy and single-crystal X-ray diffraction.
• Reactivity studies involving oxidative addition and cycloaddition reactions.

Main Results:

• Successful preparation and structural confirmation of the germylone dimNHCGe.
• Observed unusual migration of substituents (H, Me, Ph, C5F5N) from germanium to the carbene ligand upon oxidative addition.
• Formation of a Ge(IV) adduct via cycloaddition with tetrachloro-o-benzoquinone.

Conclusions:

• The synthesized germylone displays unique reactivity patterns, including ligand migration, which are not typical for germanium compounds.
• This study expands the known chemistry of germanium-NHC complexes and highlights novel reaction pathways.