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2,6-Xylenol

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2,6-Xylenol[1]
2,6-Xylenol molecule
Names
Preferred IUPAC name
2,6-Dimethylphenol
Other names
2-Hydroxy-m-xylene
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.008.547 Edit this at Wikidata
UNII
  • InChI=1S/C8H10O/c1-6-4-3-5-7(2)8(6)9/h3-5,9H,1-2H3 ☒N
    Key: NXXYKOUNUYWIHA-UHFFFAOYSA-N ☒N
  • InChI=1/C8H10O/c1-6-4-3-5-7(2)8(6)9/h3-5,9H,1-2H3
    Key: NXXYKOUNUYWIHA-UHFFFAOYAM
  • CC1=C(C(=CC=C1)C)O
Properties
C8H10O
Molar mass 122.167 g·mol−1
Melting point 43 to 45 °C (109 to 113 °F; 316 to 318 K)
Boiling point 203 °C (397 °F; 476 K)
Hazards
Flash point 86 °C (187 °F; 359 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

2,6-Xylenol is a chemical compound which is one of the six isomers of xylenol. It is also commonly known as 2,6-dimethylphenol (DMP).

A known application of DMP is in the synthesis of Mexiletine.

Production

2,6-DMP can be produced by the direct methylation of phenol. This is carried out with gaseous phenol and methanol at elevated temperatures in the presence of a catalyst[2]

2,6-Xylenol is a monomer for poly(p-phenylene oxide) engineering resins through carbon - oxygen oxidative coupling. Carbon-to-carbon dimerization is also possible. In one study 2,6-xylenol is oxidized with iodosobenzene diacetate with a fivefold excess of the phenol.[3]

In the first step of the proposed reaction mechanism the acetyl groups in the iodine compound are replaced with the phenol. This complex dissociates into an aryl radical anion and a phenoxy residue. The two aryl radicals recombine forming a new carbon-carbon covalent bond and subsequently lose two protons in a rearomatization step. The immediate reaction product is a diphenoquinone as result of a one-step 4-electron oxidation. It is nevertheless possible to synthesize the biphenol compound via a comproportionation of the quinone with xylenol already present. In this reaction sequence the hypervalent iodine reagent is eventually reduced to phenyliodine.

synthesis of 3,5,3,5-tetramethyl-biphenyl-4,4-diol

References

  1. ^ 2,6-Xylenol at Sigma-Aldrich
  2. ^ Zukowski, W.; Berkowicz, G.; Baron, J.; Kandefer, S.; Jamanek, D.; Szarlik, S.; Wielgosz, Z.; Zielecka, M. (2014). "Selective phenol methylation to 2,6-dimethylphenol in a fluidized bed of iron-chromium mixed oxide catalyst with o-cresol circulation" (PDF). Chemistry Central Journal. 8 (1): 51. doi:10.1186/s13065-014-0051-6. PMC 4172955. PMID 25342964.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  3. ^ Selective oxidative para C–C dimerization of 2,6-dimethylphenol Christophe Boldron, Guillem Aromí, Ger Challa, Patrick Gamez and Jan Reedijk Chemical Communications, 2005, (46), 5808 - 5810 Abstract