BiX₃‑Mediated Hydrohalogenations of HDDA Benzynes: An Approach to Polycyclic Aryl Halides

Here we demonstrate the hydrohalogenation reactions of HDDA benzynes promoted by BiX₃ reagents for the generation of complex aryl halides. All three bismuth(III) halides can act as the source for their respective halides, i.e., Cl^– or Br^– or I^–. The regiochemical preference for hydrohalogenation is dependent on the nature of the substituent present at the diyne terminus but neither on the linker nor on the BiX₃ reagent. The substrate scope for this transformation is broad in terms of the tethers A-B-C and the substituents R¹ and R².