Computational strategies to probe CH activation in dioxo-dicopper complexes.

Area of Science:

• Inorganic Chemistry
• Computational Chemistry
• Catalysis

Background:

• Dioxo-dicopper complexes are implicated in catalytic CH activation.
• Understanding the precise mechanism of CH activation is crucial for catalyst design.
• Two primary mechanistic pathways, oxo-insertion and radical recombination, have been proposed.

Purpose of the Study:

• To elucidate the CH activation mechanism in dioxo-dicopper complexes.
• To investigate the influence of ligand electrophilicity on reaction barriers.
• To determine the preferred catalytic pathway.

Main Methods:

• Density Functional Theory (DFT) calculations were employed.
• Energy Decomposition Analysis (EDA) was used to probe reaction pathways.
• Systematic variation of N-donor ligand electrophilicity coordinated to Copper (Cu).

Main Results:

• Electron-withdrawing ligands stabilize the oxo-insertion transition state through charge transfer.
• Lower activation barriers were observed for the oxo-insertion pathway with electron-withdrawing ligands.
• Barriers for the radical recombination mechanism showed minimal dependence on N-donor electrophilicity.

Conclusions:

• The oxo-insertion pathway is identified as the preferred mechanism for CH activation in dioxo-dicopper catalysts.
• Computational findings correlate well with experimental Hammett relationships.
• Ligand design can effectively tune catalytic activity by influencing the CH activation mechanism.