Diphenylene Dioxide誘導体の合成研究 (第21報)

Diphenylene Dioxideの合成

抄録

Examinations were made on the synthesis of diphenylene dioxide by the thermal condensation of the potassium salt of o-bromo-, o-chloro-, and o-iodophenol with copper catalyst. It was thereby clarified that, as in the case of the Ullmann reaction, the reaction proceeded most smoothly when the halogen in halophenols was bromine, unless there was an atomic group, such as the nitro radical, that activated the nuclear chlorine atom, and that the yield is the best when metallic potassium was used, rather than potassium hydroxide, in the preparation of the potassium salt, apart from the economic question. The corresponding iodo compound was found to be impracticable since the liberation of iodine occurred at below the reaction temperature.