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Structure-Reactivity Relationships in Borane-Based FLP-Catalyzed Hydrogenations, Dehydrogenations, and
1Chemistry Department, Paderborn University, Warburger Strasse 100, 33098 Paderborn, Germany.
Accounts of Chemical Research
|March 13, 2023
Summary
Frustrated Lewis pairs (FLPs) offer metal-free hydrogenation alternatives. Understanding the structure-reactivity relationship is key to advancing FLP chemistry for diverse catalytic applications.
Area of Science:
- Organometallic chemistry
- Catalysis
- Main-group chemistry
Background:
- Frustrated Lewis pairs (FLPs) are emerging as powerful metal-free catalysts for hydrogenation reactions.
- Their development offers an alternative to traditional transition metal catalysis.
- A deeper understanding of the structure-reactivity relationship in FLPs is crucial for their advancement.
Purpose of the Study:
- To provide detailed insights into the correlation between Lewis acidity/basicity and reactivity in FLPs.
- To systematically discuss FLP reactivity in various selected reactions.
- To elucidate the influence of electronic modifications on hydrogen activation and C(sp³)-H activation.
Main Methods:
- Development of a qualitative and quantitative structure-reactivity relationship for metal-free imine hydrogenation.
- Kinetic studies to determine activation parameters for FLP-mediated hydrogen activation.
- Systematic modification of Lewis acid and base components to tune reactivity for different substrates.
Main Results:
- Established structure-reactivity relationships for FLP-catalyzed hydrogenation of imines, nitroolefins, acrylates, and malonates.
- Demonstrated tunable hydrogen activation by adjusting Lewis acid and base strengths.
- Achieved C(sp³)-H activations for dehydrocouplings and dehydrogenations, as well as cycloisomerizations.
- Developed FLP systems for reductive deoxygenation of phosphine oxides and amides.
Conclusions:
- The study provides a comprehensive understanding of structure-reactivity relationships in FLP chemistry.
- This knowledge enables the rational design of FLPs for specific catalytic transformations.
- FLPs are versatile catalysts for a wide range of metal-free reactions, including hydrogenation, C-H activation, and deoxygenation.
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