Metal-Deficient Supramolecule Based on a Fivefold-Symmetric Building Block

Area of Science:

• Supramolecular Chemistry
• Organometallic Chemistry
• Materials Science

Background:

• Pentaphosphaferrocene complexes are known building blocks for supramolecular assemblies.
• Metal-deficient supramolecules offer unique properties and potential for functionalization.
• Fullerene-like structures in inorganic chemistry are of significant interest.

Purpose of the Study:

• To synthesize and characterize a novel, metal-deficient cationic supramolecule with a fullerene topology.
• To investigate the structural and chemical properties of this unprecedented compound.
• To explore its potential as a precursor for further modifications.

Main Methods:

• Selective isolation of the cationic supramolecule as a salt with a weakly coordinating anion.
• Characterization using X-ray structure analysis, powder X-ray diffraction (PXRD), NMR spectroscopy, and mass spectrometry.

Main Results:

• Successful synthesis and characterization of the cationic supramolecule [(Cp''Fe(η⁵ -P₅))₁₂ {CuNCMe}₈]⁸⁺.
• The supramolecule exhibits a metal-deficient core with a fullerene topology, featuring 12 pentaphosphaferrocene units and a minimal number of copper atoms.
• It possesses 12 vacant metal sites, the highest number reported to date, and labile acetonitrile ligands.

Conclusions:

• The synthesized compound represents the simplest homologue in its family of metal-deficient pentaphosphaferrocene-based supramolecules.
• The numerous vacant metal sites and labile ligands make it a versatile precursor for inner/outer core modifications and functionalization.