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A Protocol for Safe Lithiation Reactions Using Organolithium Reagents
Published on: November 12, 2016
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Methyllithium "On-Water" Addition on Ketone: H-Bond Network and Mechanism.
1Département de Chimie Moléculaire, UMR CNRS 5250/Université Grenoble Alpes, Grenoble Cedex, France.
Journal of Computational Chemistry
|August 13, 2025
Summary
Organolithium compounds like methyllithium can react in water, contrary to common belief. Molecular dynamics simulations reveal hydrogen bonding stabilizes these reactive species, enabling synthesis.
Area of Science:
- Organic Chemistry
- Computational Chemistry
- Physical Chemistry
Background:
- Organolithium compounds are vital in organic synthesis but highly sensitive to moisture.
- Recent studies show water can facilitate some organolithium reactions, like tetrahydrofuran synthesis.
- The mechanisms and behavior of organolithium compounds in aqueous environments are not well understood.
Purpose of the Study:
- To investigate the reaction mechanisms of methyllithium (MeLi) in the presence of water.
- To understand how MeLi behaves in aqueous-ether environments during organic reactions.
- To elucidate the role of water in stabilizing organolithium species.
Main Methods:
- Hybrid quantum mechanics/molecular mechanics (QM/MM) molecular dynamics simulations.
- Well-tempered metadynamics bias.
- Simulations conducted within a water-ether droplet solvation model.
- Examination of both dimeric and tetrameric MeLi clusters.
Main Results:
- A stabilizing hydrogen-bond network involving partially hydrolyzed MeLi dimers (MeLi2OH) and water molecules was identified.
- This network prevents complete hydrolysis of organolithium species in the ether phase, allowing product formation.
- Partially hydrolyzed tetramer clusters (MeLi4(OH)3) also support reaction progression without decomposition.
Conclusions:
- Organolithium compounds can be stabilized in aqueous-ether mixtures via specific hydrogen-bonding interactions.
- These interactions are crucial for enabling reactions previously thought to require strictly anhydrous conditions.
- The findings provide mechanistic insights into "on-water" organolithium chemistry.
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