Using COC(=O)CC1CC(c2cccc(C(=O)C(=O)c3ccc(OC(F)F)cc3)c2)C1 to produce COC(=O)C=C1CC(c2cccc(C(=O)C(=O)c3ccc(OC(F)F)cc3)c2)C1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.