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Updated: Nov 1, 2025
08:12
A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
10.2K
A Giese reaction for electron-rich alkenes
Qi Huang1, Sankar Rao Suravarapu1, Philippe Renaud1
1Department of Chemistry and Biochemistry, University of Bern Freiestrasse 3 CH-3012 Bern Switzerland philippe.renaud@dcb.unibe.ch.
Chemical Science
|June 24, 2021
Summary
A new general method enables the hydroalkylation of electron-rich alkenes using air initiation and triethylborane. This process offers favorable polar effects and achieves good to excellent diastereocontrol in stereoselective reactions.
Area of Science:
- Organic Chemistry
- Synthetic Methodology
Background:
- Electron-rich alkenes are versatile synthetic intermediates.
- Developing efficient and selective methods for their functionalization is crucial in organic synthesis.
Purpose of the Study:
- To develop a general and efficient method for the hydroalkylation of electron-rich alkenes.
- To investigate the mechanism and stereoselectivity of the developed reaction.
Main Methods:
- Hydroalkylation reactions were performed at room temperature under air initiation.
- Triethylborane was used as a chain transfer reagent.
- 4-tert-butylcatechol (TBC) served as the hydrogen atom source.
Main Results:
- A general method for hydroalkylation of various electron-rich alkenes (enol esters, enol ethers, etc.) was established.
- Favorable polar effects were identified as key to the reaction's efficiency and minimization of side reactions.
- Stereoselective hydroalkylation of chiral N-(alk-1-en-1-yl)oxazolidin-2-ones proceeded with good to excellent diastereocontrol.
Conclusions:
- The developed hydroalkylation method is broadly applicable to electron-rich alkenes.
- The reaction mechanism is supported by favorable polar effects, leading to high efficiency.
- The method demonstrates excellent stereoselectivity for chiral substrates, making it valuable for asymmetric synthesis.
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