4-Bromo-4'-fluorobiphenyl is an organic compound featuring a biphenyl core substituted with a bromine atom at the 4-position and a fluorine atom at the 4'-position. It is a white to off-white crystalline solid with a molecular formula of C12H8BrF. This compound is primarily utilized as a key synthetic intermediate in the production of advanced organic electronic materials. Its main application lies in the synthesis of organic light-emitting diode (OLED) materials, particularly as a precursor for constructing host materials, electron transport materials (ETMs), and other functional molecular frameworks. The biphenyl structure provides rigidity and planarity, while the halogen atoms (Br and F) serve as reactive handles for further cross-coupling reactions (e.g., Suzuki, Stille, or Buchwald-Hartwig couplings) to build larger, more complex π-conjugated systems essential for optoelectronic devices. As a versatile building block, it is also relevant in pharmaceutical and agrochemical research for constructing biaryl structures. It should be handled with care as an irritant and stored under inert conditions to prevent degradation.