Cyclopentadienylmanganese tricarbonyl is primarily used as an antiknock additive in gasoline, enhancing engine performance by reducing knocking and improving fuel efficiency. It serves as an alternative to lead-based additives, offering a more environmentally friendly option for fuel formulation. Additionally, it is utilized in organic synthesis as a catalyst or reagent, particularly in reactions involving carbonylation or the formation of metal-carbon bonds. Its stability and reactivity make it valuable in research and industrial processes for producing specialized chemicals and materials.