Using [Br-], CC(=O)c1ccc(NC(=O)C(F)(F)F)c(Br)c1 to produce O=C(CBr)c1ccc(NC(=O)C(F)(F)F)c(Br)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.