Editing Butylated hydroxytoluene (section)

===Industrial production===
The [[chemical synthesis]] of BHT in industry has involved the reaction of [[p-Cresol|''p''-cresol]] (4-methylphenol) with [[isobutylene]] (2-methylpropene), catalyzed by [[sulfuric acid]]:
<ref name=Ullmann>Helmut Fiege, Heinz-Werner Voges, Toshikazu Hamamoto, Sumio Umemura, Tadao Iwata, Hisaya Miki, Yasuhiro Fujita, Hans-Josef Buysch, Dorothea Garbe, Wilfried Paulus "Phenol Derivatives" in ''Ullmann's Encyclopedia of Industrial Chemistry'', Wiley-VCH, Weinheim, 2002. {{doi|10.1002/14356007.a19_313}}
Article Online Posting Date: June 15, 2000.</ref>
:CH<sub>3</sub>(C<sub>6</sub>H<sub>4</sub>)OH  +  2 CH<sub>2</sub>=C(CH<sub>3</sub>)<sub>2</sub>  →  ((CH<sub>3</sub>)<sub>3</sub>C)<sub>2</sub>CH<sub>3</sub>C<sub>6</sub>H<sub>2</sub>OH
Alternatively, BHT has been prepared from [[2,6-Di-tert-butylphenol|2,6-di-''tert''-butylphenol]] by hydroxymethylation or aminomethylation followed by [[hydrogenolysis]].{{citation needed|date = March 2020}}