(Ferrocenylmethyl)trimethylammonium bromide is an organic compound containing ammonium and bromide ions. It is commonly used as a phase-transfer catalyst in organic synthesis, particularly in the production of pharmaceuticals and agrochemicals. This compound displays strong basicity, facilitating the transfer of reactants between immiscible solvents to enable more efficient chemical reactions. Additionally, it serves as an intermediate in the synthesis of other organic compounds.