Used in organic synthesis as a key building block for creating light-emitting materials in OLED (organic light-emitting diode) devices. Its rigid spirobifluorene core enhances thermal stability and prevents crystallization in thin films, making it ideal for blue-emitting layers. Commonly employed in Suzuki-Miyaura cross-coupling reactions to construct conjugated polymers and small molecules for optoelectronic applications. Also explored in host materials for phosphorescent OLEDs due to its high triplet energy level.