Flourination

Fluorination gets a good reaction

European chemists have found that using fluorinated solvents in olefin metathesis reactions substantially improves the product yields obtained.
The metathesis reactions of alkenes (olefins) form a vital part of the armoury of transformations available to synthetic organic chemists. They provide a way of breaking and remaking carbon-carbon double bonds - allowing the substituent groups to be swapped - and are usually catalysed by transition metal complexes.
Commercially available catalysts, such as Grubbs', remain popular among chemists but are often ineffective in more difficult reactions like the multi-step total synthesis of natural products and biologically active molecules.

Commercially available catalysts remain popular among chemists but are often ineffective in more difficult reactions

Karol Grela, Polish Academy of Science, Warsaw, Poland, and colleagues have found that the yields of reactions using these catalysts can be dramatically improved by using fluorinated aromatic hydrocarbon solvents.
In particular, he reports that it is 'possible to increase the metathesis reaction yield by up to 18-times, only by changing the solvent from 1,2-dichloroethane to perfluorotoluene.'
Jie Wu, professor of chemistry at Fudan University, Shanghai, China, adds: 'This is an excellent improvement in metathesis reactions, which will find applications in the synthesis of advanced natural and biologically active compounds.'
Grela says that uncovering the nature of this effect and improving the recycling efficiency of the valuable catalysts - to satisfy the guidelines of green chemistry - are the next steps in his work.
David Parker