Using CCC(C)(C)c1cc(C(=O)CBr)cc(C(C)(C)CC)c1O, [I-] to produce CCC(C)(C)c1cc(C(=O)CI)cc(C(C)(C)CC)c1O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.