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Abstract We report the oxidative dimerization reaction of siloxydienes derived from simple enones that creates a new gamma‐gamma (γ‐γ) C−C bond using catalytic iron and benzoyl peroxide as the terminal oxidant in acetonitrile solvent at ambient temperature. The reaction shows a broad substrate scope including cyclic and acyclic siloxydienes derived from ketones, aldehydes, and esters, which are converted to 1,8‐dicarbonyl compounds under mild catalytic reaction conditions in 19–89 % yield across 30 examples. The method is suitable for the coupling of sterically demanding carbon centers, including the formation of vicinal quaternary centers. Conceptually, the dienol ether serves as a precursor to a conjugated radical cation, which undergoes highly site selective γ‐dimerization reactions. The γ‐γ dimerization strategy is applied to the synthesis of a bioactive analogue of honokiol.
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Single-Step Synthesis of γ-Ketoacids through a Photoredox-Catalyzed Dual Decarboxylative Coupling of α-Oxo Acids and Maleic Anhydrides
A photocatalytic methodology for the single step synthesis of γ-ketoacids from α-ketoacids has been developed. This method employs maleic anhydrides as traceless synthetic equivalents of acrylic acids, achieving a selective cross-coupling via a dual decarboxylative strategy, where molecular CO2 is released as the only waste byproduct. The method has also been expanded to incorporate a highly regioselective, 3-component coupling with various alcohols to access functionalized γ-ketoesters.
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- PAR ID:
- 10481214
- Publisher / Repository:
- ACS Publications
- Date Published:
- Journal Name:
- Organic Letters
- Volume:
- 25
- Issue:
- 48
- ISSN:
- 1523-7060
- Page Range / eLocation ID:
- 8634 to 8639
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acs.orglett.3c03258
