Cationic Functionalisation by Phosphenium Ion Insertion.

Area of Science:

• Organometallic Chemistry
• Inorganic Chemistry
• Materials Science

Background:

• The synthesis of novel phosphorus-containing compounds is crucial for advancing materials science and catalysis.
• Nickel complexes with phosphorus ligands offer unique electronic and structural properties.
• Understanding the reactivity of low-valent phosphorus species is key to developing new synthetic methodologies.

Purpose of the Study:

• To synthesize and characterize unprecedented polyphosphorus cations incorporating a nickel center.
• To investigate the reactivity of a nickel-phosphorus precursor with phosphenium ions.
• To explore the formation of dinuclear nickel-phosphorus complexes and their structural features.

Main Methods:

• Reaction of [Cp'''Ni(η³-P₃)] with in situ generated phosphenium ions.
• Isolation and characterization of novel polyphosphorus cations and dinuclear complexes.
• Density Functional Theory (DFT) calculations to elucidate reaction pathways and bonding.

Main Results:

• Synthesis of unprecedented polyphosphorus cations [Cp'''Ni(η³-P₄R₂)][X] and [Cp'''Ni(η³-P₄RCl)][TEF].
• Formation of unexpected dinuclear complexes [{Cp'''Ni}₂(μ,η³:η¹:η¹-P₄Br₃)][TEF] and [{Cp'''Ni}₂(μ,η³:η¹:η¹-P₄(2,2'-biphen)Cl)][GaCl₄].
• Structural analysis revealed "butterfly-like" P₄ rings in mononuclear complexes and distorted P₄ chains in dinuclear complexes.

Conclusions:

• The reaction provides a versatile route to novel nickel-stabilized polyphosphorus compounds.
• The study highlights the formation of unique P₄ ring and chain structures coordinated to nickel.
• DFT calculations offer insights into the mechanistic pathways and electronic structures of the synthesized complexes.