RuBisCO-Inspired CO₂ Activation and Transformation by an Iridium(I) Complex

Area of Science:

• Organometallic Chemistry
• Catalysis
• Inorganic Chemistry

Background:

• Carbon dioxide (CO2) utilization remains a significant challenge in chemistry.
• Developing novel catalysts for CO2 activation and transformation is crucial for sustainable chemistry.
• Enamido ligands offer unique electronic and steric properties for metal complexation.

Purpose of the Study:

• To synthesize and characterize a new iridium(I) complex featuring an enamido phosphine anion.
• To investigate the reactivity of this complex with carbon dioxide (CO2).
• To explore the potential of this system in mimicking enzymatic CO2 fixation processes.

Main Methods:

• Synthesis of the iridium(I) complex with the enamido phosphine anion (dbuP-).
• Experimental investigation of the complex's reaction with two equivalents of CO2.
• Computational analysis to elucidate reaction mechanisms and intermediates.
• Spectroscopic confirmation of the proposed Ir-CO2 intermediate.

Main Results:

• Successful synthesis of the novel iridium(I) complex.
• The complex binds two equivalents of CO2, initiating a selective reaction cascade.
• Reversible cleavage of both CO2 and the enamido ligand was observed.
• Experimental and computational evidence confirmed a stable Ir-CO2 intermediate.

Conclusions:

• The synthesized iridium(I) complex exhibits unique reactivity towards CO2.
• The observed CO2 fixation and cleavage mechanism provides insights into catalytic cycles.
• The transformation bears resemblance to enzymatic CO2 fixation by RuBisCO, suggesting potential bio-inspired catalytic applications.