= Solution
The activated aromatic pi system polarizes <bromine> and attacks its <electrophilic> end while Br–Br cleaves. This makes a C–Br bond at C1 or C3 and gives a <Wheland intermediate>. Donation from phenolic <oxygen> stabilizes contributors with positive charge at its attached ring <carbon>. <acetate> or <bromide> then removes the <proton> from the attacked <carbon>; the C–H bond <electrons> restore the aromatic pi system. Repetition at the other activated ortho site gives the dibrominated product.
\b[Each step replaces C–H by C–Br and restores <aromaticity>.] No <radical (chemistry)> initiator or benzylic abstraction is needed, and no <Lewis acid> <catalyst> should be invented for this already activated phenolic substrate. The overall substitution balance is $\mathrm{ArH_2+2Br_2\rightarrow ArBr_2+2HBr}$.
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