On May 18, 2017, Yasuda, Takuma; Park, In Seob; Yang, Yu Seok; Sumiya, Hiroshi; Fukushima, Yukio published a patent.Category: pyrazines The title of the patent was Dicyanopyrazine compound, luminescent material for light transmitter, and preparation method for 2,5-dicyano-3,6-dihalogenopyrazine. And the patent contained the following:
Dicyanopyrazine compound I [R3 = electron-donating group; R4 = H, (un)substituted aryl or electron-donating group; L3 = (un)substituted heteroarylene or (un)substituted arylene; L4 = single bond, (un)substituted heteroarylene or (un)substituted arylene; L3 and L4, together with carbon atoms to which each is attached, may combine to form a ring] and II [R5 = electron-donating group; R6 = H, (un)substituted aryl or electron-donating group; L5 = (un)substituted heteroarylene or (un)substituted arylene; L6 = single bond, (un)substituted heteroarylene or (un)substituted arylene] were provided. Organic electroluminescent device comprising an invention compound, e.g., III, showed maximum external quantum efficiency of higher than 5%. Further disclosed is a preparation method of 2,5-dicyano-3,6-dihalogenopyrazine. For example, treatment of 2,3-diamino-3-(phenylthio)acerylonitrile with citric acid-sodium citrate buffer (pH = 3.0) [1,2-dimethoxyethane, water, room temperature, 5 h, 45%] and halogenation [CuBr2, tert-Bu nitrite, acetonitrile, 70°, 5 h] afforded 2,5-dicyano-3,6-dibromopyrazine (67.0% yield). Of note, 2,5-dicyano-3,6-dihalogenopyrazine is a useful synthetic intermediate for dicyanopyrazine compound The experimental process involved the reaction of 3,6-Dibromopyrazine-2,5-dicarbonitrile(cas: 1391026-27-9).Category: pyrazines
The Article related to dicyanopyrazine light transmitter material, dicyanodihalogenopyrazine preparation cyclization halogenation, Optical, Electron, and Mass Spectroscopy and Other Related Properties: Luminescence and other aspects.Category: pyrazines