[{"from": "human", "value": "Please suggest some possible reagents that could have been used in the following chemical reaction. [C][C][C][O][C][C][Branch1][C][O][C][Cl]>>[C][C][C][O][C][C][=Branch1][C][=O][C][Cl]"}, {"from": "gpt", "value": "[C][C][Branch1][C][C][=O].[O].[O][=S][=Branch1][C][=O][Branch1][C][O][O].[Cr+6].[Cr].[O-2].[O-2].[O-2]"}]