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Updated: Apr 28, 2026

Optimization of the Ugi Reaction Using Parallel Synthesis and Automated Liquid Handling
Published on: November 11, 2008
Predicting new Ugi-smiles couplings: a combined experimental and theoretical study.
Romain Ramozzi1, Nicolas Chéron, Laurent El Kaïm
1Laboratoire de Chimie, UMR 5182, Ecole Normale Supérieure de Lyon, Université de Lyon, 46 allée d'Italie F-69364 Lyon Cedex 07 (France); Laboratoire de Chimie et Procédés, DCSO, UMR 7652, Ecole Nationale Supérieure de Techniques Avancées ParisTech, 828, Boulevard des Maréchaux, F-91762 Palaiseau Cedex (France); Département de Chimie, UMR 8640, Ecole Normale Supérieure, 24 rue Lhomond, 75231 Paris Cedex 05 (France); Present address: Fukui Institute for Fundamental Chemistry, Kyoto University, Takano-Nishihiraki-cho 34-4, Sakyou-ku, Kyoto 606-8103 (Japan).
This study explores new substrates for Ugi-Smiles couplings using theoretical calculations. Experiments confirmed predictions, yielding aryl-imidates and providing a new route to benzimidazoles.
Area of Science:
- Organic Chemistry
- Computational Chemistry
Background:
- Previous mechanistic studies focused on multicomponent Ugi-type reactions.
- Ugi-Smiles couplings represent an extension of Ugi-type reactions.
Purpose of the Study:
- To predict the efficiency of novel substrates in Ugi-Smiles couplings through theoretical calculations.
- To experimentally validate computational predictions for new reaction pathways.
Main Methods:
- Utilized theoretical calculations to assess substrate suitability for Ugi-Smiles couplings.
- Conducted experimental reactions using predicted efficient substrates, including 2,4,6-trichlorophenol and nitrosophenols.
Main Results:
- Successfully predicted and experimentally confirmed the formation of aryl-imidates from 2,4,6-trichlorophenol.
- Validated theoretical predictions identifying nitrosophenols as effective acidic partners.
- Demonstrated a novel synthetic route to benzimidazoles via Ugi-Smiles coupling with nitrosophenols.
Conclusions:
- Theoretical calculations are effective in predicting substrate efficiency for Ugi-Smiles reactions.
- Nitrosophenols serve as valuable reagents in Ugi-Smiles couplings, enabling benzimidazole synthesis.
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