Palladium-catalyzed salt-free double decarboxylative aryl allylation
Ryan A Daley1, Joseph J Topczewski
1Department of Chemistry, University of Minnesota, Minneapolis, MN 44544, USA. jtopczew@umn.edu.
Organic & Biomolecular Chemistry
|August 24, 2018
Summary
A new palladium-catalyzed reaction enables decarboxylative aryl allylation of benzoic acids with allylic carbonates. This efficient method yields up to 94% product without added salts, bases, or copper, offering a greener synthetic route.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Palladium-catalyzed cross-coupling reactions are vital in organic synthesis.
- Developing efficient methods for C-C bond formation is a continuous challenge.
- Decarboxylative strategies offer atom-economical pathways to functionalized molecules.
Purpose of the Study:
- To develop a novel palladium-catalyzed decarboxylative aryl allylation reaction.
- To utilize readily available unactivated benzoic acids and allylic carbonates.
- To establish a base- and salt-free coupling method.
Main Methods:
- Employing palladium catalysis with a suitable ligand system.
- Reacting unactivated benzoic acids with allylic carbonates.
- Optimizing reaction conditions including catalyst loading and temperature.
Main Results:
- Achieved successful decarboxylative aryl allylation between benzoic acids and allylic carbonates.
- Obtained good to excellent yields (up to 94%) for a range of substrates.
- Demonstrated a salt-free process requiring only 1 mol% palladium, without additional base, copper, or silver.
Conclusions:
- The developed palladium-catalyzed reaction provides an efficient and versatile route for aryl allylation.
- This method offers a sustainable alternative due to its mild conditions and minimal byproducts (CO2, tert-butanol).
- The reaction broadens the scope of decarboxylative coupling strategies in organic synthesis.
![Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F51444.jpg&w=3840&q=50)
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