Used primarily as a key intermediate in the synthesis of pharmaceuticals, especially in the production of certain antidepressants and antipsychotic drugs. Its structure allows for selective functionalization, making it valuable in constructing complex organic molecules. It is also employed in research settings for developing new bioactive compounds and in the preparation of fluorescent probes due to its favorable photophysical properties. Commonly utilized in multi-step organic syntheses where a substituted isobenzofuranone scaffold is required.