2-Hydroxycarbazole is an organic heterocyclic compound featuring a carbazole core with a hydroxyl substituent at the 2-position. This structure imparts unique photophysical and electronic properties, making it a valuable building block in advanced materials science. Its primary and most significant application is as a key precursor or core unit in the synthesis of organic light-emitting diodes (OLEDs) and other organic electronic materials. The carbazole moiety is renowned for its excellent hole-transporting ability, high thermal stability, and good photoluminescence quantum yield. The hydroxyl group provides a versatile handle for further functionalization, such as etherification or coupling reactions, to create more complex molecules like host materials, emitters, or charge-transport layers for OLED devices. Beyond its role in optoelectronics, 2-hydroxycarbazole serves as a versatile synthetic intermediate in organic chemistry. It is used to construct more complex heterocyclic systems and functional molecules due to its reactive phenolic and aromatic amine sites.