3,3 ,5,5 -Tetramethyl-4,4 -diphenoquinone,

The bifunctional polymer 2 (2) that is formed when oligomers of J. are heated with 3,3 , 5,5 -tetramethyl-4,4 -diphenoquinone (a byproduct of the synthesis of 1) reacts with a bifunctional coupling reagent to produce a coupled product... 

Dimethyl-4-oxo-2,5-cyclohexadien-l-ylidene)-2,6-dimethyl-2,5-cyclohexadien-l-one, 9CI. 3,3, 5,5 -Tetramethyl-4,4 -diphenoquinone [4906-22-3]... 

White (86) has extended the work of Cooper on equilibration of monomer with polymer and used it for the preparative synthesis of low molecular weight oligomers. From the reaction of 1000 g of polymer with 1000 g of 2.6-xylenol using tetramethyl diphenoquinone as initiator, he obtained... 

Equimolar amounts of 2,6-di-fert-butyl-4-methylphenol and 3,3, 5,5 -tetramethyl-diphenoquinone heated 2 hrs. at 80° in benzene under Ng 3,3, 5,5 -tetra-ferf-butylstilbenequinone and 4,4 -dihydroxy-3,3, 5,5 -tetramethylbiphenyl. Y both ca. 80%. R. G. R. Bacon and O. J. Stewart, Ghem. Gommun. 1967, 977. 

Poly(2,6-dimethyl-l,4-oxyphenylene) (poly(phenylene oxide), PPG) is a material widely used as high-performance engineering plastics, thanks to its excellent chemical and physical properties, e.g., a high 7 (ca. 210°C) and mechanically tough property. PPO was first prepared from 2,6-dimethylphenol monomer using a copper/amine catalyst system. 2,6-Dimethylphenol was also polymerized via HRP catalysis to give a polymer exclusively consisting of 1,4-oxyphenylene unit, while small amounts of Mannich-base and 3,5,3, 5 -tetramethyl-4,4 -diphenoquinone units are always contained in the chemically prepared PPO. 

The telechelica,(i -bis(2,6-dimethylphenol)-poly(2,6-dimethylphenyl-ene oxide) (PP0-20H) [174-182] is of interest as a precursor in the synthesis of block copolymers [175] and thermally reactive oligomers [179]. The synthesis has been accomplished by five methods. The first synthetic method was the reaction of a low molecular weight PPO with one phenol chain end with 3,3, 5,5 -tetramethyl-l,4-diphenoquinone. This reaction occurred by a radical mechanism [174]. The second method was the electrophilic condensation of the phenyl chain ends of two PPO-OH molecules with formaldehyde [177,178], The third method consists of the oxidative copolymerization of 2,6-dimethylphenol with 2,2 -di(4-hydroxy-3,5-di-methylphenyl)propane [176-178]. This reaction proceeds by a radical mechanism. A fourth method was the phase transfer-catalyzed polymerization of 4-bromo-2,6-dimethylphenol in the presence of 2,2-di(4-hy-droxy-3,5-dimethylphenyl)propane [181]. This reaction proceeded by a radical-anion mechanism. The fifth method developed was the oxidative coupling polymerization of 2,6-dimethylphenol (DMP) in the presence of tetramethyl bisphenol-A (TMBPA) [Eq. (57)] [182],... 

A reaction in which perchloryl fluoride functions as an ambident electrophile, somewhat analogous to Neeman s oxofluorination, was discovered by Kende and MacGregor on passing FCIOj into a suspension of sodium 2,6-dimethylphenoxide in pentane or toluene at 0°. Workup and chromatography gave 2,6-dimethylphenol, 2,6-dimethylbenzoquinone, 2,2, 6,6 -tetramethyl-4,4 -diphenoquinone and, in about 20% yield, a new compound characterized as the dimer (3) of 6-fluoro-2,6-dimethyl-... 

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