Dynamic control over catalytic function using responsive bisthiourea catalysts
M Vlatković1, J Volarić, B S L Collins
1Stratingh Institute for Chemistry, University of Groningen Nijenborgh 4, 9747 AG, Groningen, The Netherlands. b.l.feringa@rug.nl.
Organic & Biomolecular Chemistry
|September 1, 2017
Summary
Novel bisthiourea molecular motors act as catalysts, dynamically controlling activity and stereoselectivity in the Henry reaction with heat and light. These stimuli-responsive organocatalysts achieve efficient dual stereocontrol without needing a basic functional group.
Area of Science:
- Organic Chemistry
- Catalysis
- Supramolecular Chemistry
Background:
- Molecular motors offer precise control over chemical processes.
- The Henry reaction is a crucial carbon-carbon bond-forming reaction.
- Stimuli-responsive catalysts can enhance reaction efficiency and selectivity.
Purpose of the Study:
- To design and investigate novel bisthiourea molecular motor-based catalysts.
- To explore the dynamic control of catalytic activity and stereoselectivity using external stimuli (heat and light).
- To demonstrate enantioselective organocatalysis without a basic functional group in the catalyst core.
Main Methods:
- Synthesis of two novel bisthiourea molecular motor-based catalysts.
- Investigation of the Henry reaction under varying thermal and light conditions.
- Analysis of catalytic activity, stereoselectivity, and enantioselectivity using advanced spectroscopic and chromatographic techniques.
Main Results:
- The designed bisthiourea molecular motors function as effective catalysts in the Henry reaction.
- Catalytic activity and stereoselectivity were successfully modulated by external stimuli (heat and light).
- Efficient dual stereocontrol was achieved, demonstrating the potential for precise catalytic manipulation.
Conclusions:
- Novel bisthiourea molecular motors represent a new class of stimuli-responsive organocatalysts.
- External stimuli like heat and light can dynamically control catalytic performance.
- The absence of a basic functional group for stereocontrol highlights an innovative approach in enantioselective organocatalysis.
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