Hydrocarbon Activation with Metal Halides: Catalysis of the Jacobsen Rearrangement by (ZrCl4)n in the Presence of Aromatic Hydrocarbons


  • This work was supported by the Fonds National Suisse de la Recherche Scientifique (grant no. 20-40268.94) and by Ciba-Geigy SA (Basel, Switzerland).


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Extremely mild conditions suffice for the ZrCl4-mediated rearrangement of permethylated arenes at room temperature in halogenated solvents. This reaction, better known as the Jacobsen reaction, was previously observed only in concentrated sulfuric acid. In the presence of durene, (ZrCl4)n is surprisingly soluble. The active species in the reaction of C6Me6 is shown on the right.