Tetrabutylammonium chloride is widely used as a phase transfer catalyst in organic synthesis. It facilitates the transfer of reactants between immiscible phases, enhancing reaction rates and yields. In the pharmaceutical industry, it is employed in the synthesis of various drugs, particularly in alkylation and esterification reactions. Additionally, TBAC is utilized in the preparation of ionic liquids, which are valuable in green chemistry for their low volatility and recyclability. It also finds application in electrochemical studies as a supporting electrolyte due to its ability to stabilize ions in solution. In polymer chemistry, TBAC is used to modify the properties of polymers, improving their solubility and processability.