A Fluorous Super Brønsted Acid Catalyst: Application to Fluorous Catalysis without Fluorous Solvents

Abstract

The preparation of a fluorous super Brønsted acid catalyst, 4-(1H,1H-perfluorotetradecanoxy)-2,3,5,6-tetrafluorophenylbis(trifluoromethanesulfonyl)methane (3d), is described. The fluorous catalyst 3d can be recycled by using liquid/solid phase separation without fluorous solvents. A perfluorocarbon solvent is not essential for fluorous biphasic catalysis.

Key words

Brønsted acid - fluorous catalyst - ponytail - fluorous biphasic catalysis - superacid

References

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7

In the case of the esterification, the resultant solution was concentrated under reduced pressure, and the crude compounds were diluted in hexane to precipitate 3d. Thus, 3d was recovered by filtration.