Diphenylene dioxide

Swerev M (1988), Chemie und Analytik der Polychlordibenzodioxine und -dibenzofurane Muster und Quellen der PCDD und PCDFin Umweltproben . Dissertation, Universitat Ulm Tomita M, Ueda S, Narisada M (1959), Yagugaku Zasshi, Tokio 19 186-191. Studies on the dibenzo-p-dioxin (diphenylene dioxide) derivatives XXVII Synthesis of polyhalodibenzo-p-dioxins ... 

Petroleum ether is added to precipitate the sodium o-chlorophenate, which is filtered off and dried. The salt is placed in a Claisen flask with a wide side arm arranged for distillation under 4 mm. pressure. By gradual heating of the flask in a metal bath to a temperature of 250°, 31 g. (37%) of diphenylene dioxide is distilled from the flask. Crystallization of the distillate from ethanol gives 27 g. of pure product, m.p. 119°. 

First, the assumption was made that micranthine is unsubstituted at the 5-positions of the isoquinoline nuclei on the basis that no substituents are present in the 5-positions of all known bisbenzylisoquinoline alkaloids. Then, all the possible structures containing a diphenylene dioxide ring, one... 

Diphenylene dioxide Diphenyletha nedione cis-l,2-Diphenylethene tra s-l,2-Diphenylethene Diphenylethenone... 

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