Volume 94 Issue 45 | p. 10 | Concentrates
Issue Date: November 14, 2016

Sulfur hexafluoride is added to the fluorination tool box

Chemists introduce first practical method for using SF6 as a fluorinating reagent in organic synthesis
Department: Science & Technology
News Channels: Environmental SCENE, Organic SCENE
Keywords: reagents, fluorination, sulfur hexafluoride, deoxyfluorination, organic synthesis

In the ongoing quest for developing milder, safer, and more versatile fluorinating reagents, chemists at Massachusetts Institute of Technology have developed the first general strategy for using sulfur hexafluoride in organic synthesis (Angew. Chem. Int. Ed. 2016, DOI: 10.1002/anie.201608792). Sulfur hexafluoride, SF6, is a colorless, odorless, inert gas that is widely used as an insulator in electrical equipment such as high-voltage circuit breakers and as a tracer gas to check ventilation systems. But because SF6 has the highest known global warming potential for any compound, these applications are being phased out. The cheap gas could still be used to an advantage in large-scale syntheses in which SF6 is destroyed. MIT’s T. Andrew McTeague and Timothy F. Jamison may have found one option. The team created a process in which an iridium photocatalyst transfers an electron to SF6 to create a reactive radical species. The radical subsequently disintegrates, providing a source of nucleophilic fluorine. In a test reaction, the researchers used SF6 for the deoxyfluorination of allylic alcohols to form linear and branched fluorinated olefins. To improve upon the yield and product throughput, McTeague and Jamison further devised a continuous-flow process—a specialty of the Jamison lab—for the SF6 deoxyfluorinations. Overall, the results suggest that SF6 could replace some costly and/or hazardous fluorinating reagents.

[+]Enlarge
Chemists introduce first practical method for using SF6 as a fluorinating reagent in organic synthesis.
Reaction scheme shows deoxyfluorination of allylic alcohols using SF6 with a photocatalyst.
 
Chemists introduce first practical method for using SF6 as a fluorinating reagent in organic synthesis.
 
Chemical & Engineering News
ISSN 0009-2347
Copyright © American Chemical Society

Leave A Comment

*Required to comment