Synthesis and activation potential of an open shell diphosphine

Area of Science:

• Organometallic Chemistry
• Coordination Chemistry
• Tungsten Chemistry

Background:

• Paramagnetic metal complexes offer unique electronic properties for catalysis and materials science.
• Tungsten alkyne complexes are of interest due to their diverse reactivity and potential applications.
• The controlled synthesis of open-shell metal complexes with specific functional groups remains a challenge.

Purpose of the Study:

• To synthesize a novel paramagnetic tungsten(III) alkyne complex with accessible phosphine groups.
• To investigate the reactivity of this complex, particularly its interaction with nitric oxide.
• To characterize the products of nitric oxide splitting and their structural features.

Main Methods:

• Stepwise template synthesis strategy was employed for complex preparation.
• Characterization of the resulting tungsten complex using spectroscopic and analytical techniques.
• Investigation of the reaction with nitric oxide and structural elucidation of the product.

Main Results:

• Successful synthesis of a paramagnetic W(III) alkyne complex with free terminal diphenylphosphino groups.
• Observation of an unprecedented spontaneous nitric oxide (NO) splitting reaction.
• Formation of a W(II)-η²-C₂{P(NH₂)Ph₂}{P(O)Ph₂}⁺ complex containing amino phosphonium and phosphine oxide moieties.

Conclusions:

• The synthesized tungsten alkyne complex exhibits unique reactivity, including spontaneous NO splitting.
• This reaction provides a novel route to functionalized tungsten complexes with phosphine oxide and amino phosphonium groups.
• The findings contribute to the understanding of open-shell metal complex chemistry and NO transformations.