18959-31-4Relevant articles and documents
Preparation method of 4, 5-difluorophthalic acid
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, (2021/04/28)
The invention discloses a preparation method of 4, 5-difluorophthalic acid. The specific method comprises the following steps: S1: synthesis of 4, 5-difluoro-1, 2-phthalonitrile: adding 4, 5-difluoro-1, 2-dihalobenzene and polymethylhydrosiloxane into a reaction container, stirring and dissolving with N, N-dimethylacetamide, carrying out reaction, cooling after the reaction is finished, adding tri(dibenzylideneacetone)dipalladium and 1, 1 '-bis (diphenylphosphine) ferrocene under the protection of nitrogen, slowly adding zinc cyanide for reaction, cooling after the reaction is finished, adding water, adjusting the pH to 8 by using a sodium bicarbonate solution under vigorous stirring, stirring for 2 hours, standing, filtering, washing, and eluting and purifying by using an ethyl acetate mixed solvent of petroleum ether to obtain an off-white solid intermediate 4, 5-difluoro-1, 2-dicyanobenzene; and S2, synthesis of 4, 5-difluoro-1, 2phthalic acid. The process is safe, efficient, easy to operate, low in equipment requirement, low in raw material cost and easy for industrial production.
Process for the preparation of eight fluorine substituted phthalocyanine
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, (2017/04/07)
The invention relates to a method for preparing octafluoro-substituted phthalocyanine. According to the method, easily available 4,5-dichlorophthalic acid serving as a raw material is subjected to five-step reactions, namely acetic anhydride dehydration, aniline imidization, potassium fluoride fluorination, hydrolysis and one-step condensation to obtain a target product, namely an octafluoro-substituted phthalocyanine compound. The method has the advantages of low raw material cost, mild reaction condition, safe experiment operation, simple post-treatment, relatively high target product yield, high purity and the like. A novel method is provided to preparation for synthesizing octafluoro-substituted phthalocyanine compounds, synthesis researches of octafluoro-substituted phthalocyanine compounds are promoted, and more possibility is provided to application of the octafluoro-substituted phthalocyanine compounds serving as semiconductor materials in researches of dye-sensitized solar cells, organic thin-film transistors and other aspects. The method can be easily industrialized, and the obtained product has high purity and stable quality.
Intermediates in the preparation of 4,5-difluoroanthranillic acid
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, (2008/06/13)
Compounds of the formula STR1 which are intermediates in the preparation of 4,5-difluoroanthranilic acid, an intermediate itself in the synthesis of quinolone antibacterials, and methods of preparing these intermediates.