Multi-active Site Dynamics on a Molecular Cr/Co/Se Cluster Catalyst

Area of Science:

• Inorganic Chemistry
• Nanomaterials Science
• Catalysis

Background:

• Atomically precise nanoclusters offer unique catalytic properties due to their defined structures.
• Understanding the interplay between multiple active sites is crucial for designing efficient catalysts.

Purpose of the Study:

• To investigate the interconnected reactivity of the three active sites in the Cr3(py)3Co6Se8L6 nanocluster (1(py)3).
• To elucidate the mechanism of tosyl azide activation and carbodiimide formation catalyzed by this nanocluster.

Main Methods:

• Catalytic and stoichiometric studies were employed to examine tosyl azide activation.
• Isolation and crystallographic characterization of key metal-imido intermediates were performed.
• Comparative structural analysis and substrate binding studies were utilized.

Main Results:

• Key catalytically competent intermediates, including tris(imido) and mono(imido) clusters, were isolated and characterized.
• Nitrene transfer occurs via a stepwise mechanism involving sequential engagement of the three active sites.
• The chemical state of neighboring sites influences substrate affinity at individual Cr-imido sites.

Conclusions:

• The study demonstrates the interconnected reactivity of multiple active sites in a nanocluster catalyst.
• A detailed mechanistic understanding of carbodiimide formation was achieved.
• The findings provide insights into substrate binding regulation by neighboring active sites in nanocluster catalysis.