Using OB(O)c1cc(F)cc(F)c1F, Cc1c(Br)ccc(=O)n1CC(F)(F)F to produce Cc1c(-c2cc(F)cc(F)c2F)ccc(=O)n1CC(F)(F)F, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.