Using CCOC(=O)CC(=O)c1ccccc1, O=C(CBr)c1ccccc1 to produce CCOC(=O)C(CC(=O)c1ccccc1)C(=O)c1ccccc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.