[{"from": "human", "value": "Synthesize a molecule that matches the given characteristics. The molecule is the enal that is (E)-hex-2-enal substituted with an oxo group at C-4. It is an enal and an enone."}, {"from": "gpt", "value": "[C][C][C][=Branch1][C][=O][/C][=C][/C][=O]"}]