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P,N-Chelated Gold(III) Complexes: Structure and Reactivity.
Ann Christin Reiersølmoen1, Stefano Battaglia2, Andreas Orthaber3
1Department of Chemistry, Norwegian University of Science and Technology, Høgskoleringen 5, 7491 Trondheim, Norway.
Inorganic Chemistry
|November 10, 2020
Summary
Researchers developed novel P,N-chelated gold(III) complexes, overcoming phosphorus oxidation challenges in gold catalysis. These versatile catalysts enable new synthetic transformations with controlled counterions, advancing homogeneous catalysis.
Area of Science:
- Organometallic Chemistry
- Homogeneous Catalysis
- Synthetic Chemistry
Background:
- Gold(III) complexes are potent catalysts for diverse synthetic transformations.
- Understanding the mechanisms of gold(III) catalysis, especially with phosphorus ligands, remains limited.
- Phosphorus ligand oxidation by gold(III) has historically impeded their application in gold(III) catalysis.
Purpose of the Study:
- To develop a method for generating P,N-chelated gold(III) complexes resistant to ligand oxidation.
- To investigate the catalytic mechanisms of these novel gold(III) complexes.
- To demonstrate their utility in key synthetic transformations.
Main Methods:
- Generation of P,N-chelated gold(III) complexes with controlled counterions.
- Characterization using NMR spectroscopy and X-ray crystallography.
- Mechanistic studies employing density functional theory (DFT) calculations.
Main Results:
- Successful synthesis of P,N-chelated gold(III) complexes, preventing AuCl4- formation.
- Elucidation of the active catalyst formation mechanism.
- Demonstration of catalytic activity in gold(III)-mediated styrene cyclopropanation and 1,6-enyne alkoxycyclization.
Conclusions:
- P,N-chelated gold(III) complexes are readily synthesized and catalytically active.
- These complexes overcome previous limitations associated with phosphorus ligand oxidation.
- They offer a versatile platform for complex molecule synthesis via novel catalytic pathways.
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