An efficient synthesis of (E)-5-aryl(halo)methylenebicyclo[2.2.2]oct-2-enes is reported. Lewis acid-promoted carbohalogenation of 4-(3-arylprop-2-ynyl)-cyclohex-2-enols in dichloromethane proceeds rapidly to afford the exo-methylenebridged bicycles in good yields. This method also provides an easy access to (E)-5-aryl(halo)methyl-A C H T U N G T R E N N U N G enebicyclo[2.2.1]hept-2-enes from the five-membered ring 2,6-enynols. The reactions are procedurally simple and high yielding, producing the aryl(halo)methylene-bridged bicycles in minutes under air and mild conditions.

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