18-Crown-6 is used as an efficient phase transfer catalyst and as a complexing agent with a variety of small cation. It is involved in the synthesis of diaryl ethers, diaryl thioethers, and diarylamines mediated by potassium fluoride-alumina and 18-crown-6. It facilitates the solubility of potassium permanganate in benzene, which is used for oxidizing the organic compounds. It is used to accelerate various substitution reactions as well as enhances the power of nucleophiles such as potassium acetate. It is utilized in the alkylation reactions in the presence of potassium carbonate, N-alkylation of glutarimide and succinimide with dimethylcarbonate. The complex formed by its reaction with potassium cyanide acts as a catalyst in the cyanosilylation of aldehydes, ketones and quinines with trimethylsilyl cyanide (TMSCN).
