2,6-Di-tert-butylphenol

{{DISPLAYTITLE:2,6-Di-tert-butylphenol}}

{{Chembox

| Verifiedfields = changed

| Watchedfields = changed

| verifiedrevid = 477211972

| Name = 2,6-Di-tert-butylphenol

| ImageFile = 2,6-di-tert-butylphenol.svg

| ImageSize = 190

| ImageAlt = Structural formula of 2,6-di-tert-butylphenol

| ImageFile1 = 2,6-Di-tert-butylphenol 3D ball.png

| ImageSize1 = 210

| ImageAlt1 = Ball-and-stick model of the 2,6-di-tert-butylphenol molecule

| PIN = 2,6-Di-tert-butylphenol

| OtherNames = 2,6-Bis(1,1-dimethylethyl)phenol
Dibutylphenol
2,6-Bis(tert-butyl)phenol
2,6-Di(1,1-dimethylethyl)phenol
2,6-DTBP
Ethanox 701
Ethyl 701
Ethyl AN 701
Irganox L 140
Isonox 103
TK 12891

|Section1={{Chembox Identifiers

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| ChemSpiderID = 29135

| ChEBI_Ref = {{ebicite|changed|EBI}}

| ChEBI = 131421

| InChI = 1/C14H22O/c1-13(2,3)10-8-7-9-11(12(10)15)14(4,5)6/h7-9,15H,1-6H3

| InChIKey = DKCPKDPYUFEZCP-UHFFFAOYAK

| ChEMBL_Ref = {{ebicite|correct|EBI}}

| ChEMBL = 281071

| StdInChI_Ref = {{stdinchicite|correct|chemspider}}

| StdInChI = 1S/C14H22O/c1-13(2,3)10-8-7-9-11(12(10)15)14(4,5)6/h7-9,15H,1-6H3

| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

| StdInChIKey = DKCPKDPYUFEZCP-UHFFFAOYSA-N

| CASNo_Ref = {{cascite|correct|CAS}}

| CASNo = 128-39-2

| PubChem = 31405

| EC_number = 204-884-0

| RTECS = SK8265000

| UNNumber = 2430, 3077

| UNII = 21294V58PF

| SMILES = Oc1c(cccc1C(C)(C)C)C(C)(C)C

}}

|Section2={{Chembox Properties

| C =14 | H=22 | O=1

| Formula =

| MolarMass =

| Appearance = Low-melting colourless solid

| Density =

| MeltingPtC = 34 to 37

| MeltingPt_notes =

| BoilingPtC = 253

| BoilingPt_notes =

| Solubility =

}}

|Section7={{Chembox Hazards

| MainHazards =

| FlashPtC =118

| AutoignitionPt =

| GHSPictograms = {{GHS07}}{{GHS09}}

| GHSSignalWord = Warning

| HPhrases = {{H-phrases|315|319|410}}

| PPhrases = {{P-phrases|264|273|280|302+352|305+351+338|321|332+313|337+313|362|391|501}}

}}

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2,6-Di-tert-butylphenol is an organic compound with the structural formula 2,6-((CH3)3C)2C6H3OH. This colorless solid alkylated phenol and its derivatives are used industrially as UV stabilizers and antioxidants for hydrocarbon-based products ranging from petrochemicals to plastics.{{Ullmann|title=Antioxidants|author=Peter P. Klemchuk|year=2005|doi=10.1002/14356007.a03_091}} Illustrative of its usefulness, it prevents gumming in aviation fuels.

Production

2,6-Di-tert-butylphenol is prepared industrially via the Friedel–Crafts alkylation of phenol with isobutene catalyzed by aluminium phenoxide:

:C6H5OH + 2 CH2=C(CH3)2 → ((CH3)3C)2C6H3OH

In this way, approximately 2.5M kg/y are produced.{{Ullmann|author=Helmut Fiege|author2=Heinz-Werner Voges|author3=Toshikazu Hamamoto|author4=Sumio Umemura|author5=Tadao Iwata|author6=Hisaya Miki|author7=Yasuhiro Fujita|author8=Hans-Josef Buysch|author9=Dorothea Garbe|author10=Wilfried Paulus|title=Phenol Derivatives|year=2002|doi=10.1002/14356007.a19_313}} Alkylation of phenol usually favours the para-position, and a strong lewis acid such as the Al3+ ion is necessary to give selective ortho‑alkylation.{{cite journal |last1=Kolka |first1=Alfred J. |last2=Napolitano |first2=John P. |last3=Filbey |first3=Allen H. |last4=Ecke |first4=George G. |title=The ortho-Alkylation of Phenols 1 |journal=The Journal of Organic Chemistry |date=June 1957 |volume=22 |issue=6 |pages=642–646 |doi=10.1021/jo01357a014}}{{cite journal |last1=Küpper |first1=Friedrich-Wilhelm |title=A new mechanism — key for an improved synthesis of 2,6-di-tert-butylphenol |journal=Applied Catalysis A: General |date=June 2004 |volume=264 |issue=2 |pages=253–262 |doi=10.1016/j.apcata.2003.12.043|bibcode=2004AppCA.264..253K }} 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.{{cite journal |last1=Zhao |first1=F |last2=Wang |first2=P |last3=Lucardi |first3=RD |last4=Su |first4=Z |last5=Li |first5=S |title=Natural Sources and Bioactivities of 2,4-Di-Tert-Butylphenol and Its Analogs. |journal=Toxins |date=6 January 2020 |volume=12 |issue=1 |page=35 |doi=10.3390/toxins12010035 |doi-access=free |pmid=31935944|pmc=7020479 }}

Applications

Its dominant use is as an antioxidant.

2,6-Di-tert-butylphenol is used in the synthesis of 4,4′-biphenol. The process involves oxidative coupling of followed by removal of the tert-butyl groups.{{cite encyclopedia|author1=Helmut Fiege |author2=Heinz-Werner Voges |author3=Toshikazu Hamamoto |author4=Sumio Umemura |author5=Tadao Iwata |author6=Hisaya Miki |author7=Yasuhiro Fujita |author8=Hans-Josef Buysch |author9=Dorothea Garbe |author10=Wilfried Paulus |display-authors=3 |title=Phenol Derivatives|encyclopedia =Ullmann's Encyclopedia of Industrial Chemistry|year=2002|publisher=Wiley-VCH|location=Weinheim|doi=10.1002/14356007.a19_313|isbn=3527306730 }}

2,6-di-tert-butylphenol is a precursor to antioxidants and light-protection agents for the stabilization for polymers. One such case 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 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 {{LD50}} 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.

See also

References

{{Motor fuel}}

{{Antioxidants}}

{{DEFAULTSORT:Di-tert-butylphenol, 2,6-}}

Category:Antioxidants

Category:Alkylphenols

Category:Fuel antioxidants

Category:Tert-butyl compounds