121509-79-3Relevant articles and documents
Cocatalyst-Free Reduction of 4,4′-Dinitrodiphenyl Ether to 4,4′-Diaminodiphenyl Ether Over Twin-Crystal ZnxCd1?xS under Visible Light
Hu, Yujia,Yu, Guiyang,Xing, Chuanwang,Liu, Shanshan,Wei, Chuangyu,Liu, Heyuan,Jiang, Jianzhuang,Li, Xiyou
, p. 4591 - 4601 (2021/09/02)
Semiconductor-based photocatalytic conversion of solar energy is a promising method for the synthesis of high value-added chemicals. In this paper, a cocatalyst-free nano-twin crystal ZnxCd1?xS (T?ZnxCd1?xS) semiconductor was employed to achieve almost complete conversion of DNDPE and the yield of ODA product achieves >99 % in 40 min reaction time without additional hydrogen source. As far as we know, this is the first time to apply the photocatalytic technology for reducing DNDPE to ODA, and the photocatalytic efficiency has greatly exceeded the result of traditional catalytic method. Theoretical calculation and isotope labeling in situ HPLC-MS analysis demonstrates that the reduction mechanism of DNDPE is two nitro groups of DNDPE are separately instead of simultaneously reduced, following the process of DNDPE→NO2?C6H4?O?C6H4?NO→NO2?C6H4?O?C6H4?NHOH→NO2?C6H4?O?C6H4?NH2→NO?C6H4?O?C6H4?NH2→NH2?C6H4?O?C6H4?NHOH→ODA. Hydrogen protons of water, instead of ethanol, provide the hydrogen source for the photocatalytic reduction of DNDPE to ODA.
Mass production method of 4,4'-oxydianiline from 1,4-diiodobenzene
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Paragraph 0024; 0026-0037, (2020/07/02)
The present invention relates to a method for producing 4,4andprime;-oxydianiline using 1,4-diiodobenzene. After 4,4andprime;-oxybis (iodobenzene) is produced by using a Cu catalyst and 1,4-diiodobenzene in a polar solvent mixed with water, 4,4andprime;-oxydianiline can be produced through amination with ammonia introduced without a separate purification process. Therefore, compared to the conventional invention, there is an advantage in that 4,4andprime;-oxydianiline can be directly produced through amination without an intermediate purification process. In addition, expensive iodine used in the reaction is recovered as ammonium iodide and can be used again to produce 1,4-diiodobenzene, so the process efficiency is high.COPYRIGHT KIPO 2020
Preparation method of 4, 4'-diaminodiphenyl ether
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Paragraph 0012-0017, (2018/07/30)
The invention relates to a preparation method of 4, 4'-diaminodiphenyl ether. The preparation method comprises following steps: direct hydrogenation reduction of 4, 4'-dinitrodiphenyl ether with hydrogen is carried out at 135 to 145 DEG C in the presence of a palladium/carbon catalyst containing 5wt% of palladium is carried out, wherein the using amount of the palladium/carbon catalyst is controlled to be 0.6% of the amount of 4, 4'-dinitrodiphenyl ether, hydrogenation pressure is maintained to be 0.2 to 1.0MPa, and hydrogenation is carried out for 4 to 5h until the content of 4, 4'-diaminodiphenyl ether is 99.9wt% or higher, and then hydrogenation reaction is stopped; when the temperature is reduced to 70 DEG C, an obtained reaction liquid is pumped into a crystallization kettle with nitrogen, xylene and water are added, stirring is carried out for 5 to 8h at 30 to 50rpm, recrystallization is carried out, an obtained recrystallization product is subjected to centrifugation, is washedwith methanol, and is dried so as to obtain 4, 4'-diaminodiphenyl ether. The melting point ranges from 186 to 187 DEG C, the yield is 99% or higher, the preparation method is simple, the catalyst active service life is long, product purity is high, and the obtained 4, 4'-diaminodiphenyl ether can be directly adopted in synthesis of polyimides.
