Using Cc1ccc2c(Br)c(OS(=O)(=O)C(F)(F)F)c(C)cc2n1, C=C[Sn](CCCC)(CCCC)CCCC to produce C=Cc1c(C)cc2nc(C)ccc2c1Br, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.