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Updated: Nov 1, 2025
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A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
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A platform for on-the-complex annulation reactions with transient aryne intermediates.
Jason V Chari1, Katie A Spence1, Robert B Susick1
1Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA.
Nature Communications
|June 18, 2021
Summary
Researchers developed a new method for modifying organometallic complexes directly on the metal center. This chemistry-on-the-complex approach uses transient aryne intermediates to create complex molecular structures efficiently.
Area of Science:
- Organometallic Chemistry
- Synthetic Organic Chemistry
- Catalysis
Background:
- Organometallic complexes are vital in chemistry and biology.
- Traditional synthesis relies on pre-formed ligands, limiting structural diversification.
- Direct modification of ligands on metal centers (chemistry-on-the-complex) is underdeveloped.
Purpose of the Study:
- To establish a versatile platform for on-the-complex annulation reactions.
- To utilize transient aryne intermediates for efficient diversification of organometallic complexes.
- To access novel metal-ligand scaffolds through innovative synthetic strategies.
Main Methods:
- Transition metal-catalyzed annulation of organometallic complexes with in situ generated arynes.
- Generation and cycloaddition interception of organometallic complexes bearing free arynes.
- Focus on polypyridyl metal complexes as privileged scaffolds.
Main Results:
- Development of a platform for on-the-complex annulation reactions.
- Formation of up to six new carbon-carbon bonds in one variant.
- Access to unique molecular scaffolds via cycloaddition reactions in another variant.
Conclusions:
- Demonstrated an effective strategy for annulating organometallic complexes.
- Expanded the synthetic utility of strained aryne intermediates.
- Enabled the creation of complex metal-ligand architectures through direct modification.
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