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Updated: Jun 9, 2026
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A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Acceleration of nucleophilic CH activation by strongly basic solvents
Brian G Hashiguchi1, Kenneth J H Young, Muhammed Yousufuddin
1The Scripps Energy Laboratories, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458, USA.
Journal of the American Chemical Society
|August 26, 2010
Summary
A novel ruthenium catalyst (IPI)Ru(II)(OH)(n)(H2O)(m), 2, efficiently catalyzes H/D exchange in hydrocarbons. Reaction rates increase with solvent basicity, suggesting a base-modulated nucleophilic CH activation mechanism.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Organic Synthesis
Background:
- Hydrocarbon functionalization remains a significant challenge in chemistry.
- Ruthenium complexes are known catalysts for various transformations.
- Pincer ligands offer unique stability and reactivity to metal centers.
Purpose of the Study:
- To investigate the catalytic activity of a new ruthenium pincer complex, (IPI)Ru(II)(OH)(n)(H2O)(m) (2), where IPI is 2,6-diimidizoylpyridine.
- To explore the mechanism of H/D exchange reactions catalyzed by complex 2.
- To determine the effect of solvent basicity on the catalytic performance.
Main Methods:
- Synthesis and characterization of the ruthenium pincer complex (IPI)Ru(II)(OH)(n)(H2O)(m), 2.
- H/D exchange reactions between various hydrocarbons and basic solvents.
- Kinetic studies to analyze reaction rates and solvent effects.
Main Results:
- Complex 2 effectively catalyzes H/D exchange between hydrocarbons and basic solvents.
- Catalytic activity is higher compared to uncatalyzed reactions.
- Reaction rates are accelerated by increasing solvent basicity, contrary to typical observations.
Conclusions:
- The ruthenium pincer complex 2 is a potent catalyst for hydrocarbon H/D exchange.
- The observed rate acceleration with increasing solvent basicity supports a mechanism involving base-modulated nucleophilic CH activation.
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