The hydroarylation of olefins is a synthetic method for the generation of C–C bonds, opening routes for the synthesis of aromatic molecules such as ethylbenzene and cumene. The acids HF, H₂SO₄, and AlCl₃ are examples of suitable catalysts for the production of these chemicals. However, the need for more selective, safe, environmentally friendly, and sustainable processes has caused a search for alternative catalysts.

Thomas Braun, Erhard Kemnitz, and colleagues, Humboldt University of Berlin, Germany, have investigated the use of aluminium chlorofluoride (ACF, AlCl_xF_3-x, x = 0.05–0.25) for hydroarylation reactions. The extraordinary Lewis acid strength of ACF, a heterogeneous nanoscopic catalyst, promotes the formation of carbocationic-like species from fluorinated and non-fluorinated alkenes. This enhances the electrophilic character of the alkenes and allows the hydroarylation of a variety of alkenes under mild conditions, even at room temperature.

The results demonstrate the potential of ACF as a heterogeneous catalyst for the synthesis of fluorinated chemical building blocks, which are important in the pharmaceutical, agrochemical, and materials sciences.

• Heterogeneous Catalytic Hydroarylation of Olefins at a Nanoscopic Aluminum Chlorofluoride ,
  Beatriz Calvo, Jan Wuttke, Thomas Braun, Erhard Kemnitz,
  ChemCatChem 2016.
  DOI: 10.1002/cctc.201600257