Used primarily as a key intermediate in organic synthesis, particularly in the preparation of functional materials for optoelectronic devices. It serves as a building block in the synthesis of carbazole-based polymers and small molecules used in organic light-emitting diodes (OLEDs) and organic photovoltaics (OPVs). Its reactive carbonyl chloride group allows for easy incorporation into larger conjugated systems, enabling the tuning of electronic and optical properties. Also employed in the development of photoconductors, hole-transport materials, and fluorescent dyes due to the inherent stability and electron-donating nature of the carbazole core. Additionally, it finds use in pharmaceutical research for constructing nitrogen-containing heterocyclic compounds with potential biological activity.