Bioinspired Tungsten Complexes Employing a Thioether Scorpionate Ligand

Area of Science:

• Organometallic Chemistry
• Coordination Chemistry
• Bioinorganic Chemistry

Background:

• Tungsten complexes are crucial in catalysis and materials science.
• Bioinspired ligands offer unique reactivity and properties.
• Sulfur-rich ligands are of interest for their coordination behavior.

Purpose of the Study:

• To synthesize and characterize novel tungsten complexes using the bioinspired, sulfur-rich scorpionate ligand [PhTt].
• To explore the coordination modes and reactivity of the [PhTt] ligand with tungsten.
• To investigate the formation of tungsten-alkyne complexes with this ligand.

Main Methods:

• Salt metathesis reactions using a tungsten precursor and Cs[PhTt].
• Ligand substitution reactions to introduce methimazole and alkyne functionalities.
• Characterization of synthesized complexes using single-crystal X-ray diffraction and NMR spectroscopy.

Main Results:

• Synthesis of five novel tungsten complexes (1-5) featuring the [PhTt] ligand.
• Discovery of unexpected reactivity leading to a bidentate (methylthio)methanide ligand in complex 2.
• Formation of tungsten-alkyne complexes where [PhTt] coordinates in a bidentate sulfur fashion.
• Identification of isomers in complex 4 due to ligand flexibility.

Conclusions:

• The [PhTt] ligand can be effectively incorporated into tungsten complexes, demonstrating its versatility.
• The sulfur-rich nature of the [PhTt] ligand influences the coordination chemistry and reactivity of tungsten.
• This work expands the library of tungsten complexes with bioinspired ligands, paving the way for new catalytic applications.