1,1-Diphenylethane is primarily used as an intermediate in organic synthesis, particularly in the production of pharmaceuticals and fine chemicals. It serves as a building block for creating more complex molecules, often in the development of active pharmaceutical ingredients (APIs). Additionally, it is utilized in the manufacture of dyes, pigments, and other specialty chemicals. Its stable aromatic structure makes it suitable for use in research and industrial processes where controlled reactions are required. In some cases, it is also employed as a solvent or additive in specific chemical formulations due to its non-reactive nature under standard conditions.