Using Brc1cncc(C[PH](c2ccccc2)(c2ccccc2)c2ccccc2)c1, CC(=O)c1cc(F)ccc1F to produce C/C(=C/c1cncc(Br)c1)c1cc(F)ccc1F, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.