Synthesis method of N-phenyl-3(4-bromophenyl) carbazole

Abstract

The invention discloses a synthesis method of N-phenyl-3(4-bromophenyl) carbazole. The synthesis method is characterized in that carbazole is selected as a raw material and is subjected to Ullmann reaction with iodobenzene to prepare N-phenyl carbazole; N-phenyl-3-bromine carbazole is synthesized by NBS (N-bromosuccinimide) bromination; N-phenyl-3-boric acid base carbazole is prepared through Grignard coupling; and N-phenyl-3-boric acid base carbazole and p-bromoiodobenzene are subjected to cross coupling to obtain N-phenyl-3(4-bromophenyl) carbazole. The method provided by the invention has the characteristics of high yield, low production cost, less three-waste emission and high target compound selectivity and yield, a high-efficiency loaded catalyst is used, and isomer is reduced.

Description

Technical field [0001] The invention belongs to the field of fine chemicals, and particularly relates to a synthesis method of N-phenyl-3-(4-bromophenyl)carbazole. Background technique [0002] Since 2000, it has been known as a new flat display technology with fantastic display characteristics. Organic electroluminescence displays and their display devices have received great attention and have begun to enter the stage of industrialization; the research on organic electroluminescence materials and the product development of organic electroluminescence devices OELD have become the most competitive frontier in the world One of the scientific fields; the newly developed OLED is only tens of nanometers thick, and its application in organic thin-film electroluminescence displays can provide a display that is truly as thin as paper; organic electroluminescence is driven by an electric field through current-carrying The phenomenon of electron injection and recombination leads to the l...

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Problems solved by technology

[0016] In the above production method, reaction i uses low-activity copper powder as a catalyst, and uses a high-boiling point solvent decahydronaphthalene (boiling point 194.6 ° C), resulting in a long reaction time. After the reaction is completed, decahydronaphthalene is concentrated and a large amount of toluene is used many times. Product I is extracted from the copper sludge, and the copper sludge is difficult to remove from the reactor

Due to the characteristics of the above raw materials, the utilization rate of raw materials in production is low and copper powder is wasted; the low activity of copper powder leads to a long production cycle; toluene is toxic and easy to generate static electricity, which poses a great threat to the health of operators and production safety; decahydronaphthalene has a high boiling point , the risk factor of the reactor increases and the reactor is difficult to clean

[0017] Reaction ii In the bromination process, tetrabutylammonium tribromide prepared by reacting bromine with tetrabutylammonium bromide is used to react with product Ⅰ, and a considerable amount of multi-substituted substances are produced in the reaction product, about 15% , this part of the multi-substitution must be purified and removed, otherwise it will affect the hole transport ability of the product and affect the luminous efficiency and life of the device, and the utilization rate of the reaction raw material elements is low

[0018] Reaction Ⅲ is that product II reacts with butyllithium at ultra-low temperature to generate a lithium substitute, and then reacts with tributyl borate to obtain product III after acidification; base lithium, which can easily cause frostbite to operators and fire accidents caused by butyl lithium and water

[0019] In reaction ⅳ, expensive Pd(0) is used as a catalyst, and the catalyst is difficult to preserve in daily experiments and production environments, which is not conducive to the requirements of industrial production; and the yield of this coupling method is not very ideal , can only reach about 73%

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