Phenylselenocyanate is primarily used in organic synthesis as a versatile reagent. It plays a significant role in the formation of carbon-selenium bonds, which are useful in creating selenides and other organoselenium compounds. These compounds are often employed in the synthesis of pharmaceuticals and agrochemicals due to their unique biological activities. Additionally, phenylselenocyanate is utilized in the preparation of selenium-containing heterocycles, which are important intermediates in medicinal chemistry. Its ability to act as a selenium donor makes it valuable in various catalytic processes and in the development of new synthetic methodologies.