A dinuclear nickel peroxycarbonate complex: CO₂ addition promotes H₂O₂ release

Area of Science:

• Bioinorganic chemistry
• Synthetic chemistry
• Coordination chemistry

Background:

• Nickel-oxygen bonds are crucial in bioinorganic and synthetic chemistry.
• Nickel complexes are implicated in organic oxidation, water oxidation, and oxygen reduction.

Purpose of the Study:

• To synthesize and characterize novel nickel coordination compounds.
• To investigate the formation and properties of nickel-bound peroxycarbonate intermediates.

Main Methods:

• Synthesis of well-defined dinuclear nickel complexes.
• Reaction of nickel complexes with carbon dioxide (CO2) and hydrogen peroxide (H2O2).
• Spectroscopic and structural analysis to characterize the nickel-bound peroxycarbonate.

Main Results:

• The first nickel-bound peroxycarbonate intermediate was successfully synthesized.
• This intermediate is stabilized by hydrogen bonding across the bimetallic nickel core.
• The nickel peroxycarbonate reversibly dissociates hydrogen peroxide, a reaction accelerated by CO2.

Conclusions:

• A novel nickel-oxygen intermediate, peroxycarbonate, has been identified.
• This discovery offers new insights into nickel's role in oxygen-related chemical transformations.
• The findings highlight the potential of nickel complexes in catalysis involving CO2 and H2O2.