Activation of pentafluoropropane isomers at a nanoscopic aluminum chlorofluoride: hydrodefluorination versus dehydrofluorination

Maëva-Charlotte Kervarec; Thomas Braun; Mike Ahrens; Erhard Kemnitz

doi:10.3762/bjoc.16.213

Activation of pentafluoropropane isomers at a nanoscopic aluminum chlorofluoride: hydrodefluorination versus dehydrofluorination

Beilstein J Org Chem. 2020 Oct 23:16:2623-2635. doi: 10.3762/bjoc.16.213. eCollection 2020.

Authors

Maëva-Charlotte Kervarec¹, Thomas Braun¹, Mike Ahrens¹, Erhard Kemnitz¹

Affiliation

¹ Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany.

Abstract

The hydrofluorocarbon 245 isomers, 1,1,1,3,3-pentafluoropropane, 1,1,1,2,2- pentafluoropropane, and 1,1,1,2,3-pentafluoropropane (HFC-245fa, HFC-245cb, and HFC-245eb) were activated through C-F bond activations using aluminium chlorofluoride (ACF) as a catalyst. The addition of the hydrogen source Et₃SiH is necessary for the activation of the secondary and tertiary C-F bonds. Multiple C-F bond activations such as hydrodefluorinations and dehydrofluorinations were observed, followed by hydroarylation and Friedel-Crafts-type reactions under mild conditions.

Keywords: C–F bond activation; aluminum fluoride; dehydrofluorination; hydrodefluorination; hydrofluorocarbons.

Grants and funding

Financial support by the CRC 1349 “Fluorine-Specific Interactions” funded by the Deutsche Forschungsgemeinschaft (gefördert durch die Deutsche Forschungsgemeinschaft (DFG)–Projektnummer 387284271–SFB 1349) is gratefully acknowledged.