(Norbornadiene)molybdenum tetracarbonyl is the organomolybdenum compound with the formula (C<sub>7</sub>H<sub>9</sub>)Mo(CO)<sub>4</sub>. Structurally, the compound consists of the norbornadiene bonded to a Mo(CO)<sub>4</sub> 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 L<sub>2</sub>Mo(CO)<sub>4</sub>. This conversion exploits the lability of the diene ligand: