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Photochemical Macrolactonization of Hydroxyaldehydes via C-H Bromination
Sakura Kodaki1, Haru Ando1, Hiroyoshi Takamura1
1Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, 3-1-1 Tsushima-Naka, Kitaku, Okayama 700-8530, Japan.
Precision Chemistry
|December 26, 2025
Summary
A new photochemical method enables macrolactone synthesis from hydroxyaldehydes. This radical macrolactonization approach offers a novel route to valuable natural products.
Area of Science:
- Organic Chemistry
- Natural Product Synthesis
- Photochemistry
Background:
- Macrolactones are crucial structural units in numerous natural products.
- Conventional macrolactone synthesis relies on seco acids, leaving hydroxyaldehyde-based methods underexplored.
- Radical-mediated macrolactonization is an emerging field with limited examples, especially using hydroxyaldehydes.
Purpose of the Study:
- To develop a novel photochemical macrolactonization method utilizing hydroxyaldehydes.
- To explore radical processes for synthesizing macrolactones from previously underutilized substrates.
- To establish an efficient and versatile synthetic route for diverse macrolactone structures.
Main Methods:
- Development of a photochemical macrolactonization reaction.
- In situ generation of acyl bromide intermediates from hydroxyaldehydes.
- Utilizing radical processes for cyclization.
Main Results:
- Successful synthesis of macrolactones with ring sizes ranging from 7 to 21.
- Achieved good yields for the target macrolactone products.
- Demonstrated the feasibility of photochemical radical macrolactonization using hydroxyaldehydes.
Conclusions:
- The developed photochemical radical macrolactonization is a promising new synthetic tool.
- This method provides an efficient route to synthesize various macrolactones from hydroxyaldehydes.
- The approach holds potential for the synthesis of complex natural products.
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