Using Br, OCCCCCCCCC(F)(F)C(F)(F)C(F)(F)C(F)(F)F to produce FC(F)(F)C(F)(F)C(F)(F)C(F)(F)CCCCCCCCBr, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.