Using CCCc1cc(C(OCOC)(C(F)(F)F)C(F)(F)F)ccc1O, BrCCCCBr to produce CCCc1cc(C(OCOC)(C(F)(F)F)C(F)(F)F)ccc1OCCCCBr, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.