Using Cc1nnnn1-c1cc(CO)cc(C(F)(F)F)c1, O=C1CCC(=O)N1Br to produce Cc1nnnn1-c1cc(CBr)cc(C(F)(F)F)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.