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Recent Advances in Enantioselective Pd-Catalyzed Allylic Substitution: From Design to Applications
Oscar Pàmies1, Jèssica Margalef1, Santiago Cañellas2
1Universitat Rovira i Virgili, Departament de Química Física i Inorgànica, C/Marcel·lí Domingo, 1, 43007 Tarragona, Spain.
Chemical Reviews
|March 19, 2021
Summary
This review details advances in palladium-catalyzed allylic substitutions, including enantioselective, decarboxylative, and oxidative reactions. It covers mechanistic insights and applications in synthesizing complex molecules.
Area of Science:
- Organic Chemistry
- Catalysis
- Asymmetric Synthesis
Background:
- Palladium-catalyzed allylic substitution is a cornerstone of modern organic synthesis.
- Understanding mechanistic pathways is crucial for developing selective catalytic systems.
Purpose of the Study:
- To review the evolution and mechanistic understanding of enantioselective, decarboxylative, and oxidative Pd-catalyzed allylic substitutions.
- To compile catalytic data and applications in complex molecule synthesis.
- To compare Pd catalysis with other metals, highlighting advantages and disadvantages.
Main Methods:
- Compilation of catalytic data and synthetic applications.
- Analysis of mechanistic aspects influencing selectivity.
- Grouped presentation of data by nucleophile type, ligand type, or reaction chronology.
Main Results:
- Detailed catalytic data for various Pd-catalyzed allylic substitution reactions.
- Examples of applications in synthesizing complex molecules.
- Discussion of key mechanistic factors for achieving high enantioselectivity.
Conclusions:
- Palladium catalysis offers versatile routes for allylic substitution with high selectivity.
- Chiral ligands play a critical role in achieving enantioselectivity.
- Further development in this field promises efficient synthesis of complex chiral molecules.
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