2,4-Dimethyl-6-tert-butylphenol

2,4-Dimethyl-6-tert-butylphenol is an alkylated phenol used industrially as an antioxidant, eg. to prevent gumming in fuels, and as an ultraviolet stabilizer. It is used in jet fuels, gasolines, and avgas. It is a clear liquid with melting point 21-23 °C and boiling point 248-249 °C. It is also used in printing industry. It is stable in acidic, neutral, and alkaline solutions, and is considered to not be readily biodegradable. It does not absorb UV light, therefore direct photodegradation is not suspected.

One of its trade names is Topanol A. It is found in antioxidant mixtures AO-30, AO-31, AO-32, IONOL K72, IONOL K78, IONOL K98, and others.

It is a suspected respiratory toxicant and is suspected to be neurotoxic.