H. Higashimura, K. Fujisawa, Y. Moro-oka
Aug 1, 1998
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Influential Citations
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Journal
Journal of the American Chemical Society
Abstract
Abstract A highly regioselective oxidative coupling of 4-phenoxyphenol (PPL) catalyzed by tyrosinase model complexes, (hydrotris(3,5-diphenyl-l-pyrazolyl)borate) copper(II) chloride (Cu(tpzb)Cl) and (l,4,7-triisopropyl-l,4,7-triazacyclononane) copper(II) dichloride (Cu(tacn)Cl 2 ), is described. The polymerization of PPL oxidized by an equimolar of 2,2'-azobisisobutyronitrile in toluene, regarded as a model system of free phenoxy radical coupling, gave C-C coupling dimers besides C-0 coupling dimers at the initial polymerization stage and yielded the polymer having no melting point. However, the polymerization of PPL catalyzed by Cu(tpzb)Cl and Cu(tacn)Cl2 under dioxygen in toluene gave no C-C coupling dimers, and hence, yielded poly(l,4-phenylene oxide) showing crystallinity with melting points.