Using CC(C)(C)OC(=O)C=[N+]=[N-], COC(=O)Cc1ccc(C=O)c(Cl)c1 to produce COC(=O)Cc1ccc(C(=O)CC(=O)OC(C)(C)C)c(Cl)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.