An Isolable Bis(Germylene)-Stabilized Plumbylone.

Area of Science:

• Organometallic Chemistry
• Main Group Chemistry
• Inorganic Synthesis

Background:

• Low-valent main group compounds are crucial for understanding bonding and reactivity.
• Stable, isolable compounds with low coordination numbers are of significant interest.
• Plumbylenes and related low-valent silicon, germanium, and tin species are challenging to synthesize and characterize.

Purpose of the Study:

• To synthesize and characterize a stable plumbylone.
• To investigate the structural, electronic, and thermal properties of the synthesized compound.
• To explore the reactivity and synthetic utility of the plumbylone.

Main Methods:

• Synthesis via reduction of a bromodigermylplumbylene using potassium graphite.
• Structural characterization using single-crystal X-ray diffraction.
• Computational studies (e.g., DFT) to determine electronic ground state and bonding.
• Reactivity studies including reactions with organic azides and germylenes.

Main Results:

• Successful synthesis of a stable plumbylone (3) from a bromodigermylplumbylene (2).
• X-ray diffraction revealed a two-coordinated Pb center with an acute Ge-Pb-Ge bond angle.
• Computational analysis indicated a singlet ground state with a Pb(0) center and suggested π-electron delocalization contributes to stability.
• The plumbylone demonstrated reactivity by delivering Pb(0) atoms and undergoing metathesis with GeCl2·dioxane.

Conclusions:

• A stable, two-coordinate plumbylone has been synthesized and structurally characterized.
• The compound exhibits high thermal stability attributed to electronic delocalization.
• The plumbylone serves as a useful synthetic precursor for other low-valent lead and germanium compounds.