Related Experiment Video
Updated: Aug 16, 2026
![[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
09:12
[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Copper-Mediated Selective Cyanofluoroolefination of Diazo Compounds with TMSCF2CN
Lu Yang1,2, Kaidi Zhu2, Rumin Huang2
1Henan Institute of Advanced Technology, Zhengzhou University, 97 Wenhua Road, Zhengzhou, Henan450003, China.
Organic Letters
|August 14, 2026
Summary
Researchers developed a new method for creating fluorinated alkenes, important for pharmaceuticals and agrochemicals. This copper-catalyzed reaction efficiently produces cyanofluoroalkenes with high selectivity and allows for late-stage functionalization.
Area of Science:
- Organic Chemistry
- Fluorine Chemistry
- Medicinal Chemistry
Background:
- Fluorinated alkenes are crucial building blocks in drug discovery and crop protection.
- Developing efficient synthetic routes to functionalized fluoroalkenes is an ongoing challenge.
Purpose of the Study:
- To establish a mild and efficient method for synthesizing cyanofluoroalkenes.
- To explore the utility of this method for late-stage functionalization of complex molecules.
Main Methods:
- Copper-mediated defluorinative coupling reaction.
- Utilized (trifluoromethyl)trimethylsilane (TMSCF2CN) and diazo compounds.
- Employed mild reaction conditions.
Main Results:
- Achieved straightforward access to highly E/Z-selective cyanofluoroalkenes.
- Demonstrated broad functional group compatibility.
- Showcased applicability in late-stage functionalization of complex molecules.
- Highlighted the cyano group as a versatile handle for further derivatization.
Conclusions:
- The developed method provides a facile route to valuable cyanofluoroalkene intermediates.
- This approach enhances the synthetic toolkit for medicinal and agrochemical research.
- The reaction's versatility supports the development of novel fluorinated compounds.
Related Concept Videos
01:20Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. For instance, arenediazonium salts react with copper(I) salts of chloride, bromide, or cyanide to form corresponding aryl chlorides, bromides, and nitriles. These reactions are named Sandmeyer reactions. Although the mechanism of this reaction is complicated, as illustrated in Figure 1, they are believed to progress via an aryl copper...
01:13Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
Bromination and chlorination of aromatic rings by electrophilic aromatic substitution reactions are easily achieved, but fluorination and iodination are difficult to achieve. Fluorine is so reactive that its reaction with benzene is difficult to control, resulting in poor yields of monofluoroaromatic products. To address this, Selectfluor reagent is used as a fluorine source in which a fluorine atom is bonded to a positively charged nitrogen.
01:11Aryldiazonium Salts to Azo Dyes: Diazo Coupling
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para position.
01:14Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1
Treating arylamines with nitrous acid gives aryldiazonium salts that are effective substrates in nucleophilic aromatic substitution reactions. The diazonio group in these salts can be easily displaced by different nucleophiles, yielding a wide variety of substituted benzenes. The leaving group departs as nitrogen gas, and this easy elimination is the driving force for the substitution reaction.
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo, or cyano...
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo, or cyano...
01:19Diazonium Group Substitution: –OH and –H
Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.
02:26Preparation and Reactions of Sulfides
Sulfides are the sulfur analog of ethers, just as thiols are the sulfur analog of alcohol. Like ethers, sulfides also consist of two hydrocarbon groups bonded to the central sulfur atom. Depending upon the type of groups present, sulfides can be symmetrical or asymmetrical. Symmetrical sulfides can be prepared via an SN2 reaction between 2 equivalents of an alkyl halide and one equivalent of sodium sulfide.