Selective hydrogenation via precise hydrogen bond interactions on catalytic scaffolds
Song Shi1,2, Piaoping Yang1, Chaochao Dun3
1Department of Chemical and Biomolecular Engineering and Catalysis Center for Energy Innovation (CCEI), University of Delaware, Newark, DE, 19716, USA.
Nature Communications
|January 26, 2023
Summary
Researchers developed new porous polymers with tailored active sites. These catalysts precisely control chemical reactions, enhancing hydrogenation rates and selectivity for specific substrates.
Area of Science:
- Materials Science
- Catalysis
- Polymer Chemistry
Background:
- Enzyme active sites influence catalyst performance via weak interactions.
- Precise synthetic control of enzyme-inspired heterogeneous catalysts is difficult.
Purpose of the Study:
- To synthesize and investigate hyper-crosslinked porous polymers (HCPs) with specific functional groups (-OH or -CH3) to tune active site environments.
- To explore the impact of these functional groups on catalytic activity and selectivity.
Main Methods:
- Synthesis of hyper-crosslinked porous polymers (HCPs) with -OH or -CH3 groups.
- Reaction rate measurements.
- Spectroscopic techniques.
- Density Functional Theory (DFT) calculations.
Main Results:
- HCP-OH catalysts significantly enhanced hydrogenation rates for H-acceptor substrates with carbonyl groups.
- Hydrophobic HCP-CH3 catalysts promoted non-H bond substrate activation.
- Functional groups partially activated the C=O bond and tuned catalytic sites.
- Selective hydrogenation of multifunctional substrates was achieved through preferential adsorption.
Conclusions:
- The functional groups on HCPs not only enhance substrate adsorption but also actively participate in bond activation and site tuning.
- This synthetic strategy provides a new class of porous polymers for selective catalysis.
- Precise control over active site environments in heterogeneous catalysts is achievable through polymer design.
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