- An unusual photo-oxidation pathway for a poly(2,6-dimethyl-1,4-phenylene oxide) model compound
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The long wavelength UV photochemistry was investigated of a model compound for poly(2,6-dimethyl-1,4-phenylene oxide). Irradiation of the phenyl-capped dimer of 2,6-dimethyl phenol at wavelengths >290 nm with UVA-340 fluorescent lamps in the absence of oxygen gave no detectable products after 27 days. Very low conversion to oxidation products was found in the presence of oxygen, but about 20% conversion to products in which solvent had added to the benzylic methyl groups occurred under aerobic conditions when the solvents had readily abstractable hydrogen atoms. A mechanism is proposed involving the facile, reversible abstraction of a benzylic hydrogen by oxygen as a first step in the oxidation. The hydroperoxyl radical that is formed can abstract hydrogen atoms from 2° and 3° carbons of the solvent, and these radicals can combine with the benzylic radicals to give the solvent adducts.
- Pickett, James E.
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- Preparation method of diphenyl ether structural compound (by machine translation)
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The invention discloses a preparation method of a diphenyl ether structural compound, and belongs to the technical field of chemical engineering. The synthesis conditions are mild, water is used as a solvent, a one-pot method is used for synthesizing a target product, and the yield is high. Compared with the traditional Ullmann reaction, the method has the advantages of wide raw material source, low reaction temperature, pure product and high yield, and can be used as a preferred method for synthesizing important medicines and pesticide products or organic intermediates. (by machine translation)
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Paragraph 0015
(2020/06/05)
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- Selective oxidative para C-C dimerization of 2,6-dimethylphenol
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Mechanistic investigations on the oxidative coupling of 2,6-dimethylphenol have led to the development of a selective and efficient procedure to prepare 3,5,3′,5′-tetramethyl-biphenyl-4,4′-diol, via a C-C coupling, mediated by a hypervalent form of iodine, i.e. (diacetoxyiodo)benzene and for which a mechanism is proposed. The Royal Society of Chemistry 2005.
- Boldron, Christophe,Aromi, Guillem,Challa, Ger,Gamez, Patrick,Reedijk, Jan
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p. 5808 - 5810
(2008/02/02)
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