2,4-Di-tert-butylphenol (2,4-DTBP) is a white solid with a phenolic odour.

It is primarily used as a raw material for the production of several commercially important antioxidants and phenolic benzotriazole-type UV absorbers.

The butylation of phenol is typically achieved by a Friedel-Crafts alkylation with isobutylene catalysed by a strong acid.

The isobutylene can be generated in situ by the dehydration of tert-butyl alcohol or methyl tert-butyl ether, which being liquids are simpler to handle than the highly flammable isobutylene gas.

[2] 2,4-DTBP is used in the production of antioxidants like tris(2,4-di-tert-butylphenyl)phosphite.