2,6-Dimethylphenol

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).
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 an 5 fold excess of the phenol.
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.