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A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Phase-vanishing halolactonization of neat substrates
Nicole Windmon1, Veljko Dragojlovic
1Department of Chemistry, Florida Atlantic University, 777 Glades Road, Boca Raton, Florida 33431, USA.
Beilstein Journal of Organic Chemistry
|October 23, 2008
Summary
Phase-vanishing reactions utilize perfluoroalkanes to separate reagents, enabling solvent-free halolactonization. This method efficiently produces lactones from various substrates, offering good to excellent yields.
Area of Science:
- Organic Chemistry
- Green Chemistry
Background:
- Phase-vanishing reactions are a novel approach in organic synthesis.
- They employ a perfluoroalkane phase screen to separate reactants without dissolution.
Purpose of the Study:
- To investigate the efficacy of phase-vanishing conditions for halolactonization reactions.
- To explore the use of this method for synthesizing lactones from neat substrates, avoiding solvents and basic conditions.
Main Methods:
- Utilizing triphasic reactions with a perfluoroalkane phase screen.
- Applying halolactonization to gamma,delta-alkenoic acids and their methyl esters.
- Employing bromine (Br(2)) and iodine monochloride (ICl) as electrophiles.
Main Results:
- Successful halolactonization of neat substrates under phase-vanishing conditions.
- Good to excellent yields obtained, especially for rigid bicyclic systems.
- Demonstrated suitability for both solid and liquid substrates.
Conclusions:
- Phase-vanishing halolactonization is an efficient, solvent-free method for lactone synthesis.
- This technique offers a greener alternative to traditional methods.
- Iodine monochloride is a superior electrophile for iodolactonization compared to iodine.
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