Using ClCc1ccc(Cl)c(Cl)c1, COC(=O)Cc1c(C(=O)OC)[nH]c2ccccc12 to produce COC(=O)Cc1c(C(=O)OC)n(Cc2ccc(Cl)c(Cl)c2)c2ccccc12, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.