[{"from": "human", "value": "Use the given information to create a molecule that fulfills the desired purpose. The molecule is an acyl chloride obtained by substitution of both hydrogens of formaldehyde by chlorine. It is functionally related to a formaldehyde."}, {"from": "gpt", "value": "[C][=Branch1][C][=O][Branch1][C][Cl][Cl]"}]