![Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F51444.jpg&w=3840&q=50)
Computational perspective on Pd-catalyzed C-C cross-coupling reaction mechanisms
Max García-Melchor1, Ataualpa A C Braga, Agustí Lledós
1Departament de Química, Edifici C.n, Universitat Autònoma de Barcelona , 08193 Cerdanyola del Vallès, Catalonia, Spain.
Accounts of Chemical Research
|July 16, 2013
Summary
Computational chemistry, particularly density functional theory (DFT), is crucial for understanding complex palladium-catalyzed C-C cross-coupling reactions. This work elucidates reaction mechanisms, aiding in developing new substrates and improving selectivity.
Area of Science:
- Organic Chemistry
- Computational Chemistry
- Catalysis
Background:
- Palladium-catalyzed C-C cross-coupling reactions are vital in organic synthesis.
- Reaction mechanisms are complex due to multiple steps and competing pathways.
- Short-lived intermediates hinder experimental mechanistic elucidation.
Purpose of the Study:
- To summarize computational studies, primarily DFT, on palladium-catalyzed C-C cross-coupling mechanisms.
- To elucidate the mechanistic complexity and clarify specific reaction steps.
- To provide insights for expanding reaction scope and refining selectivity.
Main Methods:
- Application of computational chemistry, predominantly Density Functional Theory (DFT).
- Analysis of key catalytic steps: oxidative addition, transmetalation, and reductive elimination.
- Investigation of related processes like direct arylation.
Main Results:
- Clarified the role of coordination number in oxidative addition selectivity.
- Enhanced understanding of transmetalation in Suzuki-Miyaura, Stille, Negishi, and Sonogashira reactions.
- Rationalized the effect of ligand substitution on reductive elimination and the role of bases in direct arylation.
Conclusions:
- Computational chemistry significantly improves the understanding of palladium-catalyzed cross-coupling reactions.
- Mechanistic complexity has been identified, and mechanisms clarified in specific cases.
- Modern computational tools are capable of handling complex systems and solving specific mechanistic problems.
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