Using CS(=O)(=O)c1ccc(C2=C(Br)C(=O)CC2)cc1, C[Sn](C)(C)c1ccc(Br)cn1 to produce CS(=O)(=O)c1ccc(C2=C(c3ccc(Br)cn3)C(=O)CC2)cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.