Oxidation of the tris(carbene)borate complex PhB(MeIm)3MnI(CO)3 to MnIV[PhB(MeIm)3]2(OTf)2.

Area of Science:

• Organometallic Chemistry
• Coordination Chemistry
• Ligand Design

Background:

• Tris(carbene)borate ligands are versatile in coordination chemistry.
• Manganese carbonyl complexes are important in catalysis and materials science.
• Understanding ligand electronic effects is crucial for tuning metal complex properties.

Purpose of the Study:

• To synthesize and characterize a novel manganese(I) tricarbonyl complex featuring a tris(carbene)borate ligand.
• To investigate the electronic properties and stability of the resulting complex.
• To evaluate the donating ability of the tris(carbene)borate ligand in manganese complexes.

Main Methods:

• Reaction of PhB(MeIm)3- with [Mn(CO)3(tBuCN)Br]2 to form the target complex.
• Infrared (IR) spectroscopy to analyze carbonyl stretching frequencies.
• Cyclic voltammetry to probe redox properties.

Main Results:

• Successful synthesis of the manganese(I) tricarbonyl complex, PhB(MeIm)3Mn(CO)3.
• The complex exhibits O2-sensitivity, undergoing conversion to a homoleptic MnIV complex.
• IR and cyclic voltammetry data indicate the exceptionally strong donating nature of the tris(carbene)borate ligand.

Conclusions:

• The tris(carbene)borate ligand is a powerful electron donor.
• The synthesized manganese complex's O2-sensitivity is linked to the strong donating ability of the ligand.
• This work provides insights into the reactivity and electronic structure of manganese complexes with strong donor ligands.