Unlocking a Ferrocenium Superoxidizer with the Perfluorinated Cp* Ligand.

Area of Science:

• Organometallic Chemistry
• Fluorine Chemistry
• Electrochemistry

Background:

• Ferrocene derivatives are versatile organometallic compounds with tunable electronic properties.
• Developing stronger oxidizers is crucial for advancing catalytic and synthetic methodologies.
• Highly fluorinated ligands can significantly alter the electronic characteristics of metal complexes.

Purpose of the Study:

• To synthesize a novel, highly fluorinated ferrocene derivative.
• To investigate the electrochemical properties and oxidizing strength of the new compound.
• To explore the potential applications of this potent organometallic oxidizer.

Main Methods:

• Photolytic arene displacement reaction to synthesize the ferrocene.
• Electrochemical analysis (cyclic voltammetry) to determine redox potentials.
• Reactions with known substrates to demonstrate oxidizing capabilities.

Main Results:

• Successful synthesis of the benchstable, highly fluorinated ferrocene [Fe(C5H5)(C5(CF3)5)].
• Achieved an unprecedented oxidation potential (E1/2 = 1.35 V vs. Fc/Fc+) for a ferrocene derivative.
• Generated the highly oxidizing ferrocenium salt [Fe(C5H5)(C5(CF3)5)][AsF6], the strongest known isolable organometallic oxidizer.
• Demonstrated its strength through double oxidation of [Fe(C5(CH3)5)2] and C-H activation of ortho-terphenyl.

Conclusions:

• The perfluorinated ligand imparts extreme electron-withdrawing properties, leading to exceptionally high oxidation potentials.
• This new ferrocene and its ferrocenium derivative expand the scope of strong oxidizers in organometallic chemistry.
• The compound's stability, solubility, and recyclability offer practical advantages for its use as a potent, selective oxidant.