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Published on: January 16, 2016
Multicomponent reactions are accelerated in water
Michael C Pirrung1, Koushik Das Sarma
1Department of Chemistry, Levine Science Research Center, Duke University, Durham, North Carolina, 27708, USA. michael.pirrung@duke.edu
Journal of the American Chemical Society
|January 15, 2004
Summary
Water accelerates Ugi and Passerini reactions significantly, offering up to 300-fold rate enhancements. Products precipitate from aqueous solutions, simplifying isolation and enabling library synthesis.
Area of Science:
- Organic Chemistry
- Green Chemistry
Background:
- Ugi and Passerini reactions are powerful multicomponent reactions.
- Traditional organic solvents can pose environmental and isolation challenges.
Purpose of the Study:
- To investigate the acceleration of Ugi and Passerini reactions in aqueous solutions.
- To explore the benefits of using water as a reaction medium for these transformations.
Main Methods:
- Performing Ugi and Passerini reactions in aqueous solutions.
- Comparing reaction rates in water versus organic solvents.
- Utilizing product insolubility for isolation by precipitation.
Main Results:
- Significant rate enhancements observed in aqueous solutions, approaching 300-fold compared to organic solvents.
- Products of the reactions were often insoluble in water, facilitating direct isolation.
- The methodology was successfully applied to synthesize three small combinatorial libraries.
Conclusions:
- Aqueous solutions provide a green and efficient medium for Ugi and Passerini reactions.
- Water-based reactions offer advantages in both reaction speed and product isolation.
- This approach is suitable for the rapid preparation of chemical libraries.
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