Terminal Cyanate in Stabilizing Mononuclear Cu(III) Complex: Room Temperature Preparation, Characterization, and...

Area of Science:

• Coordination Chemistry
• Organometallic Chemistry
• Catalysis

Background:

• Late transition metal oxidants are crucial for C─H bond functionalization via proton coupled electron transfer (PCET).
• Tuning terminal ligands is a key strategy for developing new metal oxidants.

Purpose of the Study:

• To develop a unique high-valent metal-cyanate oxidant.
• To investigate its reactivity in C─H and O─H bond activation and functionalization.

Main Methods:

• Synthesis and characterization of high-valent metal-cyanate complexes using X-ray crystallography, spectroscopy (UV-vis, NMR, Raman, FT-IR, EPR), and mass spectrometry.
• Kinetic studies, product analysis, and computational methods to elucidate reaction mechanisms.

Main Results:

• A novel high-valent copper-cyanate complex, [(L)Cu^III(NCO)], was synthesized and characterized.
• The complex activates C─H and O─H bonds via a hydrogen atom transfer mechanism with rates comparable to known oxidants.
• Direct C─N bond formation was achieved through C─H activation and cyanate group transfer.
• Solvent-dependent reactivity was observed.

Conclusions:

• High-valent metal-cyanates represent a new class of oxidants for strong C─H bond functionalization.
• The electronic and structural properties of the cyanate ligand suggest potential for novel coordination and bioinspired oxidation chemistry.