2-tert-Butyl-4,6-dimethylphenol

Uses

6-tert-Butyl-2,4-xylenol is an antioxidant found used in rocket and jet fuels.

Application

2-tert-Butyl-4,6-dimethylphenol has been the subject of extensive research due to its diverse biochemistry and organic synthesis applications. This compound serves as a reagent in organic synthesis, facilitating the production of heterocyclic compounds. Additionally, it acts as a catalyst in such syntheses. Its mechanism of action is not yet fully elucidated, but it is believed to involve the activation of diverse signaling pathways. It is used as an antioxidant, e.g., to prevent fuel gumming and as an ultraviolet stabilizer. It is used in jet fuels, gasoline, and avgas.

General Description

A yellow liquid with a phenolic odor. Insoluble in water and about the same density as water. Exposure to skin, eyes or mucous membranes may cause severe burns.

Air & Water Reactions

Insoluble in water.

Reactivity Profile

Phenols, such as 2-tert-Butyl-4,6-dimethylphenol, do not behave as organic alcohols, as one might guess from the presence of a hydroxyl (-OH) group in their structure. Instead, they react as weak organic acids. Phenols and cresols are much weaker as acids than common carboxylic acids (phenol has Ka = 1.3 x 10^[-10]). These materials are incompatible with strong reducing substances such as hydrides, nitrides, alkali metals, and sulfides. Flammable gas (H2) is often generated, and the heat of the reaction may ignite the gas. Heat is also generated by the acid-base reaction between phenols and bases. Such heating may initiate polymerization of the organic compound. Phenols are sulfonated very readily (for example, by concentrated sulfuric acid at room temperature). The reactions generate heat. Phenols are also nitrated very rapidly, even by dilute nitric acid. Nitrated phenols often explode when heated. Many of them form metal salts that tend toward detonation by rather mild shock.

Health Hazard

TOXIC; inhalation, ingestion or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.

Fire Hazard

Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated.

Synthesis

1. weigh 2,4-dimethylphenol (1500 g) and zinc pellets (100 g) in a 10 L round bottom flask. 2. The reaction mixture was heated to induce the reaction of zinc with 2,4-dimethylphenol with simultaneous release of hydrogen. 3. After complete reaction of the zinc spheres, the temperature of the reaction system was lowered to 70 °C. The temperature of the reaction system was then lowered to 70 °C. 4. slowly add isobutylene to the flask to start the alkylation reaction. 5. monitor the increase in volume of the reaction mixture during the reaction. When the volume expands to 5-8 times the initial volume, the reaction is stopped. 6. A sample was taken and analyzed by gas chromatography, which showed that the product composition was: 2-(tert-butyl)-4,6-dimethylphenol (96.1%), unreacted 2,4-dimethylphenol (2.4%), and ethyl ether alkanol (1.5%) as a by-product. 7. The calculated selectivity of 2-(tert-butyl)-4,6-dimethylphenol was 96.1% and the conversion of 2,4-dimethylphenol was 97.6%.

References

[1] Patent: CN106495992, 2017, A. Location in patent: Paragraph 0045; 0046; 0047; 0048
[2] Bulletin de la Societe Chimique de France, 1958, p. 856
[3] Industrial and Engineering Chemistry, 1943, vol. 35, p. 264,270
[4] Industrial and Engineering Chemistry, 1943, vol. 36, p. 655,659
[5] Patent: US4163008, 1979, A