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