Using O=C(O)c1cc(Cl)c(F)cc1F, OCC1(C(F)(F)F)CCCC1 to produce O=C(O)c1cc(Cl)c(OCC2(C(F)(F)F)CCCC2)cc1F, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.