341-58-2Relevant articles and documents
Homocoupling of a Grignard Reagent toward the Synthesis of 2,2′-Bis(trifluoromethyl)-4,4′-diaminobiphenyl
Nakatani, Jiro,Nozoe, Tatsuhiro
supporting information, p. 2442 - 2446 (2021/11/13)
A new process for the synthesis of 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl (TFMB) comprising three steps has been industrially developed. The first step is the homocoupling of the Grignard reagent derived from 1-chloro-2-(trifluoromethyl)benzene with iron chloride(III) in the presence of an oxidizing agent to afford 2,2′-bis(trifluoromethyl)biphenyl. The second step is the nitration of this biphenyl to 2,2′-bis(trifluoromethyl)-4,4′-dinitrobiphenyl, and the third step is the reduction of this dinitrobiphenyl using hydrogen over Pd/C to afford TFMB. This process has been demonstrated on an industrial scale.
Synthesis method of 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl
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, (2021/06/13)
The invention discloses a synthesis method of 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl. The method comprises the following steps: subjecting 2-chloro-5-aminobenzotrifluoride serving as a starting raw material and acyclic anhydride in a formula I to amidation to obtain an intermediate II, then carrying out reductive coupling reaction on the intermediate II to obtain an intermediate III, and finally carrying out deamidation reaction on the intermediate III to obtain the 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, wherein the cyclic anhydride in the formula I is succinic anhydride, glutaric anhydride, adipic anhydride or maleic anhydride. The starting material 2-chloro-5-aminobenzotrifluoride is an important farm chemical and medical intermediate, and is low in price, convenient and easy to obtain; the synthesis route is short, the reaction condition is mild, and the method is environment-friendly; the total yield of the synthetic route can reach 60-80%, and compared with the prior art, the synthetic route has obvious advantages and is suitable for industrial mass production.
Preparation Method for 2,2'-Bis(Trifluoromethyl)-4,4'-Diaminobiphenyl
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Paragraph 0026-0037, (2021/07/20)
The present invention relates to a method for producing 3,3 '- bis 2,2 - diaminobiphenyl by a benzidine rearrangement reaction from' -4 bis hydrazinobenzene in high yield, and more specifically, to dissolve 4 3,3 '-' - bis hydrazinobenzene in (A) organic solvent. (B) The solution prepared in (A) is added dropwise to an inorganic acid solution while maintaining a temperature below 0 °C.30°C. When the (C) titration is completed, less than 0 °C -30°C or less is reacted. 2,2 '- Bis -4, 4' - diaminobiphenyl, which is characterized in that it comprises.