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