Used as a phase-transfer catalyst in organic synthesis, facilitating reactions between reagents in different phases by transferring ions into organic solvents. Commonly applied in nucleophilic substitutions, esterifications, and polymerizations where solubility of ionic reactants is limited. Also employed in electrochemistry as a supporting electrolyte due to its good ionic conductivity and stability in solution. Useful in analytical chemistry for ion-pairing applications and in the preparation of functionalized materials.