Description
Methyltrioctylammonium chloride is a water insoluble quaternary ammonium salt, which is widely used as a counter ion in solvent extraction of anionic metal complexes. It is widely used as a phase transfer catalyst for the catalytic oxidation of cyclohexene to 1,6-hexanedioic acid. In comparison to traditional method of oxidizing cyclohexanol or cyclohexanone with nitric acid or potassium permanganate, the usage of methyltrioctylammonium chloride is a more environmentally friendly reaction.
Reference
N. Pourreza, H. Zavvar Mousavi, Determination of cadmium by flame atomic absorption spectrometry after preconcentration on naphthalene– methyltrioctylammonium chloride adsorbent as tetraiodocadmate (II) ions, Analytica Chimica Acta, 2004, vol. 503, pp. 279-282
Chemical Properties
viscous colourless to pale orange liquid
Uses
Mixture of C
8 and C
10 chains with C
8 predominating. Used as a metal extraction reagent and a phase-transfer catalyst.
Uses
Methyltrioctylammonium chloride can be used:
- As a catalyst in the synthesis of acridine dione derivatives from aromatic aldehyde, dimedone and amines under ultrasonic irradiations.
- As a catalyst in the synthesis of extended π-systems using aromatic aldehydes and methyldiazines.
- As a component of a catalytic system used in the Suzuki-Miyaura cross-coupling reaction of a variety of aryl and heteroaryl chlorides in H2O.
Definition
ChEBI: An organic chloride salt having methyltrioctylammonium as the cation.
Flammability and Explosibility
Not classified
Safety Profile
Poison by ingestion and
intraperitoneal routes. When heated to
decomposition it emits very toxic fumes of
NOx, NH3, and Cl-.
Synthesis
Weigh 1000g of trioctylamine in a beaker, add concentrated hydrochloric acid drop by drop (HCl added about 103g), magnetic stirring, neutralization reaction after the end of a constant temperature water bath evaporation to remove about 80% of the water, and then vacuum drying to get the product of trioctylammonium chloride; were weighed 1,000g of trioctylammonium chloride and 235g of dimethyl carbonate, in turn, added to the 10L kettle, nitrogen purge to drive away the air inside the kettle, the reaction temperature 170 , the reaction time of 8 hours; the end of the reaction to produce methyl trioctylammonium chloride of about 1026g. After purging with nitrogen to drive out the air inside the kettle, the reaction was carried out in closed condition at a reaction temperature of 170 , and the stirring was started after the reaction temperature reached 170 , and the reaction time was 8 hours; at the end of the reaction, about 1026g of methyltrioctylammonium chloride was produced.
Purification Methods
A 30% (v/v) of Aliquat 336 solution in *benzene is washed twice with an equal volume of 1.5M HBr. [Petrow & Allen, Anal Chem 33 1303 1961.] It is purified by dissolving 50g in CHCl3 (100mL) and shaking with 20% NaOH solution (200mL) for 10minutes, and followed by 20% NaCl (200mL) for 10minutes. It is then washed with a small volume of H2O and filtered through a dry filter paper [Adam & Pribil Talanta 18 733 1971]. n-Alkylammonium chloride n=2,4,6. Recrystallise them from EtOH or an EtOH/Et2O mixture. [Hashimoto & Thomas J Am Chem Soc 107 4655 1985, Chu & Thomas J Am Chem Soc 108 6270 1986.] n-Alkyltrimethylammonium bromide n=10,12,16. Recrystallise them from an EtOH/Et2O mixture. [Hashimoto & Thomas J Am Chem Soc 107 4655 1985.]
