Method for recovering 2,4-dinitrophenol hydrogenation reduction byproduct to prepare 2-amino-4-acetamidoanisole

Abstract

The invention discloses a method for recovering 2,4-dinitrophenol hydrogenation reduction byproduct to prepare 2-amino-4-acetamidoanisole. The method comprises the following steps: separating a 2-amino-4-nitrophenol and 2-nitro-4-aminophenol mixture to obtain a 2-nitro-4-aminophenol single component; mixing the 2-nitro-4-aminophenol with an alkylation reagent, and carrying out a phenolic hydroxyl group alkylation reaction and an amino group acylation reaction to obtain 2-nitro-4-acetamidoanisole; and carrying out nitro group reduction on the 2-nitro-4-acetamidoanisole to obtain the 2-amino-4-acetamidoanisole. The method provides a brand new method for the synthesis of the fine chemical engineering intermediate 2-amino-4-acetamidoanisole with important uses, reduces the content of organic matters in 2-amino-4-nitrophenol production wastewater, reduces the treatment difficulty of enterprises' industrial wastewater, converts wastewater components into the fine chemical engineering intermediate with important production uses, and increases the enterprises' economy income.

Description

technical field [0001] The invention relates to a method for preparing organic compounds, in particular to a method for recovering and preparing 2-amino-4-acetamidoanisole by utilizing 2,4-dinitrophenol hydrogenation reduction by-products. Background technique [0002] 2-Amino-4-acetylaminoanisole, commonly known as "reduced substance", is an important coupling component intermediate of disperse dyes, and is widely used in the synthesis of dyes, such as 291# blue, 79# blue, etc. [0003] The process for synthesizing 2-amino-4-acetamidoanisole mainly includes two routes: Route 1 [CN101880242B, CN106242990A], using p-aminoanisole as the main starting material, and obtaining p-acetamidobenzene through high-temperature acylation with acetic acid Methyl ether; p-acetamidoanisole reacts with mixed acid to obtain 2-nitro-4-acetamidoanisole; because the iron powder reduction process has been listed as a prohibited process by the Ministry of Environmental Protection, at present, seve...

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Problems solved by technology

Compared with the two processes, each has its own advantages and disadvantages. The product of route 1 has high quality, less impurities and has been circulated in the market for a long time. The downstream users understand its components. During the synthesis of dark blue esterification liquid or 291:1 coupling components No special process adjustment is allowed, but this process involves a large amount of dilute acid wastewater that is difficult to treat. Although sulfuric acid in dilute acid wastewater can be converted into ammonium sulfate, since this ammonium sulfate contains a large amount of organic residues, it can be used as a fertilizer Use will cause immeasurable pollution to farmland and water systems

Route 2 does not involve nitrification reaction, which effectively avoids the production of nitrification waste acid water. However, there are very few manufacturers using this process for large-scale production. The product quality is unstable and the amount of impurities is large. Unpredictable process problems and quality problems, therefore, the process described in Route 2 still needs to be continuously improved

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