2,6-Di-''tert''-butylphenol is an

organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...

with the structural formula 2,6-((CH₃)₃C)₂C₆H₃OH. This colorless solid

alkyl In organic chemistry, an alkyl group is an alkane missing one hydrogen. The term ''alkyl'' is intentionally unspecific to include many possible substitutions. An acyclic alkyl has the general formula of . A cycloalkyl group is derived from a cy ...

ated

phenol Phenol (also known as carbolic acid, phenolic acid, or benzenol) is an aromatic organic compound with the molecular formula . It is a white crystalline solid that is volatile and can catch fire. The molecule consists of a phenyl group () ...

and its derivatives are used industrially as UV stabilizers and

antioxidant Antioxidants are Chemical compound, compounds that inhibit Redox, oxidation, a chemical reaction that can produce Radical (chemistry), free radicals. Autoxidation leads to degradation of organic compounds, including living matter. Antioxidants ...

s for

hydrocarbon In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and Hydrophobe, hydrophobic; their odor is usually fain ...

-based products ranging from petrochemicals to plastics. Illustrative of its usefulness, it prevents gumming in

aviation fuel Aviation fuels are either petroleum-based or blends of petroleum and synthetic fuels, used to power aircraft. They have more stringent requirements than fuels used for ground applications, such as heating and road transport, and they contain add ...

Production

2,6-Di-''tert''-butylphenol is prepared industrially via the Friedel–Crafts alkylation of phenol with

isobutene Isobutylene (or 2-methylpropene) is a hydrocarbon with the chemical formula . It is a four-carbon branched alkene (olefin), one of the four isomers of butylene. It is a colorless flammable gas, and is of considerable industrial value. Productio ...

catalyzed by aluminium phenoxide: :C₆H₅OH + 2 CH₂=C(CH₃)₂ → ((CH₃)₃C)₂C₆H₃OH In this way, approximately 2.5M kg/y are produced. Alkylation of phenol usually favours the para-position, and a strong

lewis acid A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any ...

such as the Al³⁺ ion is necessary to give selective ortho‑alkylation. If a conventional brønsted acid is used then 2,4-di-tert-butylphenol will be produced instead.

Natural occurrence

Two species of plants, '' Jastropa curcas'' and '' Metaplexis japonica'', contain 2,6-DTBP in seeds.

Applications

Its dominant use is as an antioxidant. 2,6-di-''tert''-butylphenol is a precursor to more complex compounds used as antioxidants and light-protection agents for the stabilization for polymers. Of particular note is methyl-3-(3,5-di-''tert''-butyl-4-hydroxyphenyl)-propionate (CAS# 6386-38-5), which is formed by the Michael addition of methyl acrylate. This compound is used as a feedstock in the synthesis of more complex antioxidants such as Irganox 1098. 2,6-Di-''tert''-butylphenol is also used in the synthesis of CGP-7930, probucol, and nicanartine.

Safety and regulation

The is 9200 mg/kg, indicating a low toxicity. 2,6-Di-tert-butylphenol is covered by the U.S. Department of Transportation Code of Federal Regulations 49 CFR 172.101, Appendix B (20 Dec 2004). This substance is designated by the U.S. Department of Transportation (DOT) as a marine pollutant.

References

{{DEFAULTSORT:Di-tert-butylphenol, 2,6- Antioxidants Alkylphenols Fuel antioxidants Tert-butyl compounds

Production

Natural occurrence

Applications

Safety and regulation

See also

References