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Updated: Jan 6, 2026
Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Intermolecular Radical Addition to Ketoacids Enabled by Boron Activation
Shasha Xie1, Defang Li1,2, Hanchu Huang1
1State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis , Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road , Shanghai 200032 , China.
Researchers developed a new method for radical addition to carbonyls using visible light and boron activation. This approach efficiently synthesizes diverse lactates and pharmaceutical precursors under mild, metal-free conditions.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Photochemistry
Background:
- Intermolecular radical addition to carbonyls is challenging due to alkoxyl radical fragmentation.
- Constructing quaternary carbon centers via radical addition to ketones remains a synthetic hurdle.
Purpose of the Study:
- To develop a novel visible-light-induced method for intermolecular radical addition to α-ketoacids.
- To enable the synthesis of diverse lactates and pharmaceutical precursors.
Main Methods:
- Visible-light photoredox catalysis combined with Lewis acid activation.
- Utilizing alkyl boronic acids as radical precursors.
- In situ boron complex formation to stabilize intermediates.
Main Results:
- Successful intermolecular alkyl boronic acid addition to α-ketoacids under visible light.
- Synthesis of diversely substituted lactates at room temperature.
- Demonstrated scalability of pharmaceutical precursor synthesis under metal-free flow conditions.
Conclusions:
- The boron activation strategy overcomes challenges in radical addition to carbonyls.
- This method provides a mild, efficient, and scalable route to valuable organic compounds.
- The approach is versatile, applicable to various alkyl radical precursors.
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