Phenethyl p-Toluenesulfonate is primarily used as an intermediate in organic synthesis, particularly in the production of various pharmaceuticals and fine chemicals. It serves as a key reagent in the formation of phenethyl derivatives, which are valuable in the development of active pharmaceutical ingredients (APIs). Additionally, it is employed in the synthesis of complex organic molecules, including those used in agrochemicals and specialty chemicals. Its role as a sulfonate ester makes it useful in alkylation and acylation reactions, contributing to the creation of compounds with specific functional properties.