[{"from": "human", "value": "What reagents could have been utilized in the following chemical reaction? [O][=C][C][=C][C][=C][Branch1][Ring1][C][=O][C][=C][Ring1][Branch2]>>[O][=C][C][=C][C][=C][Branch1][Ring1][C][O][C][=C][Ring1][Branch2]"}, {"from": "gpt", "value": "[C][C][O].[BH4-1].[Na+1]"}]