Using CC(C)(C)OC(=O)N1CCC(O)(C(=O)c2cc(Br)ccc2F)CC1 to produce CC(C)(C)OC(=O)N1CCC2(CC1)Oc1ccc(Br)cc1C2=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.