Mild complexation protocol for chiral Cp^xRh and Ir complexes suitable for in situ catalysis

Area of Science:

• Organometallic Chemistry
• Asymmetric Catalysis

Background:

• Chiral cyclopentadienyl (Cp^x) ligands are crucial in asymmetric catalysis.
• Existing complexation methods can be complex and require stringent conditions.

Purpose of the Study:

• To develop a practical and user-friendly complexation method for chiral Cp^x iridium and rhodium complexes.
• To enhance the applicability of Cp^x ligands in asymmetric catalysis through improved complexation.

Main Methods:

• Utilizing free Cp^xH with stable, commercially available rhodium(I) and iridium(I) salts.
• Employing mild reaction conditions that do not require exclusion of air and moisture.
• Performing Density Functional Theory (DFT) calculations to elucidate reaction mechanisms.

Main Results:

• A straightforward complexation procedure was established, suitable for *in situ* applications.
• DFT calculations confirmed an intramolecular proton abstraction pathway.
• Development of novel TMS-containing trisubstituted Cp^x ligands leading to enhanced enantioselectivities.

Conclusions:

• The developed method offers a practical and user-friendly approach to Cp^x metal complex synthesis.
• The *in situ* complexation capability significantly boosts the utility of Cp^x ligands in asymmetric catalysis.
• The new ligands show promise for improved enantioselective synthesis of valuable compounds like dihydroisoquinolones.