Alkylation of Arenes with Benzylic and Propargylic Alcohols – Classical versus Fancy Catalysts

Gold chloride and BF 3 ⋅etherate were tested as Friedel–Crafts catalysts in the propargylation of electron‐rich arenes: differences in reactivity of the catalysts can be used to achieve high selectivity either for monoalkylation or for multiple alkylation products. In the case of a macrocyclization towards a heterocalixarene, gold catalysts exhibited a pronounced selectivity, whereas p ‐toluenesulfonic acid as catalyst opened up a competing pathway to a structural isomer.