Gold Difluorocarbenoid Complexes: Spectroscopic and Chemical Profiling

Area of Science:

• Organometallic Chemistry
• Carbene Complexes
• Gold Chemistry

Background:

• Gold carbenes ([LAu=CR2]+) require stabilizing substituents for spectroscopic analysis.
• The [LAu]+ fragment offers limited stabilization to the carbene center.
• Electron-donating substituents are typically needed to stabilize carbene complexes.

Purpose of the Study:

• To investigate the stability and reactivity of gold difluorocarbene complexes.
• To understand the electronic properties and bonding in [LAu=CF2]+ systems.
• To explore the behavior of electron-deficient gold carbenes with model substrates.

Main Methods:

• Synthesis and spectroscopic characterization of gold difluorocarbene complexes.
• Reactions with weakly coordinating anions (triflate, triflimide).
• Reactions with stilbene as a model substrate to probe carbenium ion chemistry.

Main Results:

• Difluorocarbene complexes ([LAu=CF2]+) are highly electron-deficient.
• These complexes strongly sequester weakly coordinating anions.
• Reactions with stilbene demonstrate characteristic carbenium ion chemistry.

Conclusions:

• Fluorine substituents provide insufficient π-donation for stabilizing gold carbenes.
• The electron deficiency drives unusual anion binding and reactivity patterns.
• Gold difluorocarbene complexes serve as valuable models for carbenium ion chemistry.