Using BrBr, COc1ccc(O)c(C[P+](c2ccccc2)(c2ccccc2)c2ccccc2)c1 to produce COc1cc(Br)c(O)c(C[P+](c2ccccc2)(c2ccccc2)c2ccccc2)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.