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A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
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Insights into plasmon induced keto-enol isomerization
Wei Zhang1, Jie Kong1, Huaxiang Chen2
1Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China. andong@iccas.ac.cn and University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
Nanoscale
|February 12, 2020
Summary
Plasmon-induced hot carriers offer catalytic alternatives for chemical reactions. This study reveals hot hole transfer from gold nanoparticles drives keto-enol isomerization in 2-mercapto-4(3H)-quinazolinone, offering insights into catalyzed reactions.
Area of Science:
- Catalysis
- Materials Science
- Physical Chemistry
Background:
- Plasmon-induced hot carriers are emerging as efficient catalysts, offering sustainable alternatives in chemical synthesis.
- Localized surface plasmon resonance (LSPR) in noble metal nanoparticles can generate energetic carriers for driving chemical transformations.
- Understanding reaction mechanisms at the nanoscale is crucial for designing advanced catalytic systems.
Purpose of the Study:
- To investigate the keto-enol isomerization of 2-mercapto-4(3H)-quinazolinone (MQ) driven by plasmon-induced hot carriers.
- To elucidate the role of hot hole transfer in the isomerization mechanism using surface-enhanced Raman scattering (SERS).
- To explore the potential of SERS and theoretical calculations in understanding hot carrier-mediated catalysis.
Main Methods:
- Time-dependent surface-enhanced Raman scattering (SERS) spectroscopy to monitor the keto-enol isomerization.
- Adsorption of 2-mercapto-4(3H)-quinazolinone (MQ) molecules onto gold nanoparticles (GNPs) via Au-S bonds.
- Theoretical calculations to support experimental observations and mechanistic insights.
Main Results:
- The keto-enol isomerization of MQ on GNPs was successfully monitored using time-dependent SERS.
- Experimental evidence indicated that the isomerization is initiated by hot hole transfer from GNPs to adsorbed MQ molecules.
- SERS spectra provided detailed information about the molecular changes during the isomerization process.
Conclusions:
- Hot hole transfer from gold nanoparticles is identified as the key mechanism driving the keto-enol isomerization of MQ.
- This study highlights the utility of SERS spectroscopy in probing nanoscale catalytic processes.
- The findings contribute to a deeper understanding of hot carrier-catalyzed chemical reactions and their potential applications.
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