[{"from": "human", "value": "From the provided chemical reaction, propose some possible reagents that could have been used. [Br][Br].[C][S][C][=C][C][=C][C][Branch1][C][Cl][=C][Ring1][#Branch1][C][#N]>>[C][S][C][=C][C][=C][Branch1][C][Br][C][Branch1][C][Cl][=C][Ring1][Branch2][C][#N]"}, {"from": "gpt", "value": "[Cl][C][Branch1][C][Cl][Branch1][C][Cl][Cl].[Cl][C][Cl].[I][I].[Fe]"}]