In this work, we developed a novel method to synthesize 1,1,2-tribromoethyl arenes, which can be easily transformed to 1-bromoalkynes via base-mediated elimination reaction. The bromination reagent was in situ generated from the reaction of NaBr/NaBrO₃/H₂SO₄, resulting in high reactivity, excellent chemical selectivity and outstanding functional group tolerance. Moreover, 1,1,2-tribromoethyl arenes encounter a selectivity switch to afford α-bromoketones under strong acidic conditions.