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Updated: Oct 17, 2025
A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Metal-Catalyzed Haloalkynylation Reactions
Mathis Kreuzahler1, Gebhard Haberhauer1
1Institut für Organische Chemie, Universität Duisburg-Essen, Universitätsstraße 7, 45117, Essen, Germany.
Metal catalysis enables new synthetic chemistry, like haloalkynylation, which adds halogens and alkynes to unsaturated bonds. Recent gold catalysis advances rapidly drive this field, influencing reaction selectivity.
Area of Science:
- Synthetic organic chemistry
- Organometallic chemistry
Background:
- Metal catalysis has transformed synthetic chemistry, enabling efficient synthesis of complex molecules.
- Haloalkynylation is a key transformation, transferring both a halogen and an alkynyl group to unsaturated carbon-carbon bonds.
Purpose of the Study:
- To review the advancements in metal-catalyzed haloalkynylation reactions over the past decade.
- To summarize the reactivity of various unsaturated systems (arynes, alkenes, alkynes) in these reactions.
- To highlight the impact of gold catalysis on recent developments and selectivity.
Main Methods:
- Literature review of metal-catalyzed haloalkynylation reactions.
- Analysis of reaction mechanisms and outcomes for different unsaturated substrates.
- Discussion of catalyst influence on regio- and stereoselectivity.
Main Results:
- Significant progress in metal-catalyzed haloalkynylation since its inception approximately ten years ago.
- Diverse applications using arynes, alkenes, and alkynes as unsaturated systems.
- Rapid development in recent years, particularly driven by gold-catalyzed systems.
- Demonstrated influence of the catalytic system on the regio- and stereoselectivity of the addition.
Conclusions:
- Metal-catalyzed haloalkynylation is a powerful tool for constructing complex molecules.
- Gold catalysis has emerged as a highly effective system for these transformations.
- Understanding catalyst choice is crucial for controlling reaction selectivity.
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