Using COC(=O)/C=C/C=C/c1ccc(C(=O)OC(C)(C)C)cc1C to produce COC(=O)CCCCc1ccc(C(=O)OC(C)(C)C)cc1C, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.