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Updated: Dec 29, 2025
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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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Keteniminium-Driven Umpolung Difunctionalization of Ynamides
Shubham Dutta1, Shengwen Yang2,3, Rajeshwer Vanjari1
1School of Chemistry, University of Hyderabad, Hyderabad, India.
Angewandte Chemie (International Ed. in English)
|February 9, 2020
Summary
This study introduces a novel palladium-catalyzed reaction for synthesizing triaryl-substituted enamides from ynamides, aryl diazonium salts, and aryl boronic acids. The method achieves unprecedented regioselective unsymmetrical diarylation of ynamides, yielding a single isomer.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Ynamides are versatile synthetic intermediates.
- Palladium-catalyzed cross-coupling reactions are crucial in organic synthesis.
- Developing regioselective methods for constructing tetrasubstituted olefins remains a challenge.
Purpose of the Study:
- To develop a novel three-component coupling reaction for synthesizing triaryl-substituted enamides.
- To achieve regioselective unsymmetrical 1,2-diarylation of ynamides.
- To explore the scope, functional-group tolerance, and synthetic utility of the developed method.
Main Methods:
- A three-component palladium-catalyzed coupling reaction involving ynamides, aryl diazonium salts, and aryl boronic acids.
- Utilized DFT calculations to elucidate the reaction mechanism and regioselectivity.
- Investigated the chemoselectivity and synthetic potential of the enamide products.
Main Results:
- Successfully synthesized novel triaryl-substituted enamides.
- Achieved the first example of umpolung regioselective unsymmetrical syn-1,2-diarylation/aryl-olefination of ynamides.
- Demonstrated broad scope with 68 examples and excellent functional-group tolerance.
- Confirmed regioselectivity and mechanistic pathway through DFT calculations.
Conclusions:
- The developed three-component coupling reaction provides an efficient and regioselective route to N-bearing tetrasubstituted olefins.
- The methodology offers broad applicability and high functional-group tolerance.
- The study expands the synthetic utility of ynamides in palladium-catalyzed transformations.
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