[{"from": "human", "value": "Generate a molecule based on this description. The molecule appears as a clear colorless liquid. Flash point 140 \u00b0F. Less dense than water and insoluble in water. Vapors heavier than air."}, {"from": "gpt", "value": "[C][C][Branch1][C][C][C][C][=Branch1][C][=O][C][C][Branch1][C][C][C]"}]