Using CS(=O)(=O)OCCCCC(F)(F)C(F)(F)C(F)(F)C(F)(F)F, [I-] to produce FC(F)(F)C(F)(F)C(F)(F)C(F)(F)CCCCI, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.