Diisopropylamine hydroiodide is primarily used in organic synthesis as a reagent or intermediate. It is particularly effective in the preparation of quaternary ammonium compounds, which are widely used in surfactants, disinfectants, and phase-transfer catalysts. The compound also finds application in the synthesis of pharmaceuticals, where it acts as a key building block for various active ingredients. Additionally, it is utilized in the production of agrochemicals, contributing to the development of herbicides and pesticides. Its role in facilitating specific chemical reactions, such as alkylation and acylation, makes it valuable in research and industrial processes.