Using CCOC(=O)C(Oc1ccc(Cl)cc1)(C(F)(F)F)C(F)(F)F to produce O=C(O)C(Oc1ccc(Cl)cc1)(C(F)(F)F)C(F)(F)F, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.