[{"from": "human", "value": "From the provided chemical reaction, propose some possible reagents that could have been used. [C][C][O][C][=Branch1][C][=O][N][C][C][N][C][C][Ring1][=Branch1].[O][C][C][C][Br]>>[C][C][O][C][=Branch1][C][=O][N][C][C][N][Branch1][Branch1][C][C][C][O][C][C][Ring1][#Branch2]"}, {"from": "gpt", "value": "[C][C][#N].[O][=C][Branch1][C][O-1][O-1].[K+1].[K+1]"}]