Unexpected solid-solid reaction upon preparation of KBr pellets and its exploitation in supramolecular cation...

Area of Science:

• Coordination Chemistry
• Supramolecular Chemistry
• Solid-State Chemistry

Background:

• Cobalt(III) complexes with carboxylate ligands are of interest for their structural diversity.
• Supramolecular chemistry explores the assembly of molecules into larger networks.
• Solid-state reactions offer alternative pathways for complex synthesis.

Purpose of the Study:

• To investigate the solid-state reactivity of [CoIII(eta 5-C5H4COOH)(eta 5-C5H4COO)] with alkali metal salts.
• To explore the formation of supramolecular complexes via solid-solid interactions.
• To compare solid-state synthesis with solution crystallization.

Main Methods:

• Infrared (IR) spectroscopy for sample characterization.
• Solid-state grinding (pressing) of cobalt(III) complex with KBr.
• Solution crystallization.
• Analysis of supramolecular complex formation.

Main Results:

• Pressing [CoIII(eta 5-C5H4COOH)(eta 5-C5H4COO)] with KBr resulted in the formation of the supramolecular complex [CoIII(eta 5-C5H4COOH)(eta 5-C5H4COO)]2.K+Br-.
• The same complex was obtained through solution crystallization.
• Similar solid-solid supramolecular complexation was observed with K[PF6] and [NH4][PF6].

Conclusions:

• Solid-state pressing is an effective method for inducing supramolecular complex formation in cobalt(III) systems.
• This approach provides a novel route for synthesizing supramolecular coordination compounds.
• The observed reactivity highlights the potential of solid-state reactions in coordination chemistry.