Di-tert-butyltetrahydrodinaphthophosphine is a sterically hindered, electron-rich phosphine ligand. Its structure features a rigid, chiral tetrahydrodinaphthyl backbone with two bulky tert-butyl substituents on the phosphorus atom, which significantly enhances its air stability compared to many other phosphines. This ligand is primarily employed in the field of materials chemistry, specifically in the synthesis of organic light-emitting diodes (OLEDs) and other organic electronic materials. It serves as a crucial component in the preparation of organometallic complexes, particularly iridium(III) and platinum(II) complexes, which are widely used as highly efficient phosphorescent emitters in OLED devices. The ligand's steric bulk and electronic properties are key to tuning the photophysical properties (such as emission color and quantum yield) and stability of these metal complexes. Beyond its role in materials science, it is also a valuable ligand in synthetic chemistry for transition metal-catalyzed cross-coupling reactions, such as Suzuki-Miyaura couplings, where it can improve catalyst activity and selectivity.