(Norbornadiene)molybdenum tetracarbonyl is the organomolybdenum compound with the formula (C7H9)Mo(CO)4. Structurally, the compound consists of the norbornadiene bonded to a Mo(CO)4 fragment. The compound is a yellow, volatile solid. It is prepared by thermal or photochemical substitution of molybdenum hexacarbonyl. The compound was originally examined as a potential antiknock agent. (Norbornadiene)molybdenum tetracarbonyl is a precursor to other derivatives of the type L2Mo(CO)4. This conversion exploits the lability of the diene ligand: (C7H9)Mo(CO)4 + 2 L → C7H9 + L2Mo(CO)4