Aliquat 336 (Starks' catalyst) is a

quaternary ammonium salt In chemistry, quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure , R being an alkyl group or an aryl group. Unlike the ammonium ion () and the primary, secondary, or tertiary ammonium cations ...

used as a

phase transfer catalyst In chemistry, a phase-transfer catalyst or PTC is a catalyst that facilitates the transition of a reactant from one phase into another phase where reaction occurs. Phase-transfer catalysis is a special form of heterogeneous catalysis. Ionic reac ...

and metal extraction reagent. It contains a mixture of C₈ (octyl) and C₁₀ (decyl) chains with C₈ predominating. It is an

ionic liquid An ionic liquid (IL) is a salt in the liquid state. In some contexts, the term has been restricted to salts whose melting point is below a specific temperature, such as . While ordinary liquids such as water and gasoline are predominantly made of ...

Applications

Organic Chemistry

Aliquat 336 is used as a phase transfer catalyst, including in the catalytic oxidation of

cyclohexene Cyclohexene is a hydrocarbon with the formula C6H10. This cycloalkene is a colorless liquid with a sharp smell. It is an intermediate in various industrial processes. Cyclohexene is not very stable upon long term storage with exposure to light an ...

to 1,6-hexanedioic acid. This reaction is more environmentally friendly. It is an example of

green chemistry Green chemistry, also called sustainable chemistry, is an area of chemistry and chemical engineering focused on the design of products and processes that minimize or eliminate the use and generation of hazardous substances. While environmental che ...

, compared with the traditional method of oxidizing

cyclohexanol Cyclohexanol is the organic compound with the formula HOCH(CH2)5. The molecule is related to cyclohexane by replacement of one hydrogen atom by a hydroxyl group. This compound exists as a deliquescent colorless solid with a camphor-like odor, whic ...

cyclohexanone Cyclohexanone is the organic compound with the formula (CH2)5CO. The molecule consists of six-carbon cyclic molecule with a ketone functional group. This colorless oily liquid has an odor reminiscent of acetone. Over time, samples of cyclohexan ...

with

nitric acid Nitric acid is the inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but older samples tend to be yellow cast due to decomposition into oxides of nitrogen. Most commercially available nitri ...

potassium permanganate Potassium permanganate is an inorganic compound with the chemical formula KMnO4. It is a purplish-black crystalline salt, that dissolves in water as K+ and , an intensely pink to purple solution. Potassium permanganate is widely used in the c ...

, which produce hazardous wastes. Aliquat 336 was used in the total synthesis of manzamine A by Darren Dixon in an early step to the electrophile.

Solvent extraction of metals

{{Main, Liquid–liquid extraction Aliquat 336 has been used for the extraction of metals, it does so by acting as a liquid

anion exchanger Ion exchange is a reversible interchange of one kind of ion present in an insoluble solid with another of like charge present in a solution surrounding the solid with the reaction being used especially for softening or making water demineralised, ...

. It is often used while diluted in hydrocarbon solvents such as aromatic

kerosene Kerosene, paraffin, or lamp oil is a combustible hydrocarbon liquid which is derived from petroleum. It is widely used as a fuel in aviation as well as households. Its name derives from el, κηρός (''keros'') meaning "wax", and was regi ...

. It is possible to use it in aliphatic kerosene but in such solvents often a phase modifier (typically a long chain alcohol) must be added to prevent the formation of third phase.

Waste treatment

Several applications have been successfully carried out with Aliquat 336, such as the recovery of acids or

acid salts In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a ...

, or the removal of certain metals from waste water. In addition, foaming has also been controlled by using this agent during the treatment of wastewater containing

anionic An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convent ...

surfactants

References

Quaternary ammonium compounds Chlorides Catalysts Ionic liquids