Synthesis of Unprecedented 4d/4f-Polypnictogens

Area of Science:

• Organometallic Chemistry
• Inorganic Chemistry
• Materials Science

Background:

• Molybdenum pnictide complexes serve as versatile precursors.
• Divalent samarocenes offer unique reductive capabilities.
• Exploration of novel polyarsenide and polystibine structures is ongoing.

Purpose of the Study:

• To synthesize and characterize new 4d/4f-polyarsenides and -polystibines.
• To investigate the reactivity of Mo-pnictide complexes with samarocenes.
• To discover unprecedented ligand architectures in organometallic chemistry.

Main Methods:

• Reductive conversion of Mo-pnictide precursor complexes.
• Utilizing two different divalent samarocenes: [Cp*₂ Sm] and [(Cp^Me4nPr )₂ Sm].
• Isolation and characterization of resulting polyarsenide and polystibine compounds.

Main Results:

• Isolation of a planar tetrastibacyclobutadiene ligand from Mo-stibide reduction.
• Isolation of a tetraarsacyclobutadiene and a side-on coordinated As₂ ^2- anion from Mo-arsenide reduction.
• The As₂ ^2- species is proposed as an intermediate in tetraarsacyclobutadiene formation.

Conclusions:

• Successful synthesis of novel 4d/4f-polyarsenides and -polystibines.
• Discovery of unprecedented tetrastibacyclobutadiene and tetraarsacyclobutadiene ligands.
• Elucidation of reaction pathways involving pnictide anions and organometallic complexes.