4-Chlorobutyronitrile is primarily used as an intermediate in organic synthesis, particularly in the production of pharmaceuticals and agrochemicals. It serves as a key building block for the synthesis of various compounds, including active pharmaceutical ingredients (APIs) and fine chemicals. Its reactivity allows for the introduction of functional groups, making it valuable in the development of complex molecules. Additionally, it is employed in the manufacture of specialty chemicals used in research and industrial applications. Its role in facilitating chemical transformations underscores its importance in synthetic chemistry.