Aromatization via a Dibromination-Double Dehydrobromination Sequence: A Facile and Convenient Synthetic Route to 2,6-Bis(trifluoroacetyl)phenols

Dmitri V. Sevenard; Olesya Kazakova; Ralf-Matthias Schoth; Enno Lork; Dmitri L. Chizhov; Jörn Poveleit; Gerd-Volker Röschenthaler

doi:10.1055/s-2008-1067080

PAPER

Aromatization via a Dibromination-Double Dehydrobromination Sequence: A Facile and Convenient Synthetic Route to 2,6-Bis(trifluoroacetyl)phenols [1]

Dmitri V. Sevenard*^a,2, Olesya Kazakova^a, Ralf-Matthias Schoth^a, Enno Lork^a, Dmitri L. Chizhov^b, Jörn Poveleit^a, Gerd-Volker Röschenthaler*^a
^a Institute of Inorganic & Physical Chemistry, University of Bremen, Leobener Str., 28334 Bremen, Germany
Fax: +49(421)2208409; e-Mail: sevenard@hfc-chemicals.com; Fax: +49(421)2184267; e-Mail: gvr@chemie.uni-bremen.de;
^b Institute of Organic Synthesis, Russian Academy of Sciences Ural Branch , S. Kovalevskoy Str. 22, GSP-147, 620041 Ekaterinburg, Russian Federation

Abstract

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Abstract

An efficient and reliable method to synthesize 2,6-bis(trifluoroacetyl)phenols bearing various substituents in the 4-position was developed. These valuable fluorinated building blocks were obtained from the corresponding cyclohexanones in a facile and convenient procedure, demonstrated to be superior to the traditional approaches. The application of this methodology to cyclohexane-1,4-dione opened access to 2,5-bis(polyfluoroacyl)-1,4-hydroquinones. Structural peculiarities of the obtained phenols as well as their 1,3-dicarbonyl or 1,3,5-tricarbonyl precursors are discussed on the basis of multinuclear NMR spectroscopy.

Key words

fluorinated compounds - arenes - ketones - aromatization - phenols

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Referenzen

References

This work was presented in part at the 18th International Symposium on Fluorine Chemistry, Bremen, Germany, 30 July-4 August 2006.

Present address: Hansa Fine Chemicals GmbH, BITZ, Fahrenheit Str. 1, 28359 Bremen, Germany.

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