42 results about "P-nitroanisole" patented technology

The invention relates to a preparation method for p-anisidine. In the presence of a ternary amorphous alloy catalyst being Ni-Mo-B or Ni-Co-P, liquid-phase p-nitroanisole is subjected to hydrogenation through intermittent hydrogenation, and therefore p-anisidine with a selectivity of more than 99.7% can be obtained. In the preparation method, reaction conditions are mild, the solvent and the catalyst can be recycled, and the preparation method is liable to industrial production.

The invention relates to a method for preparing m-nitrochlorobenzene, o-nitrochlorobenzene and p-nitrochlorobenzene by using nitrochlorobenzene meta-position oil. The method comprises the following steps of: separating the nitrochlorobenzene meta-position oil containing 20 to 45 percent of m-nitrochlorobenzene and produced in the conventional nitrochlorobenzene production process into an m-nitrochlorobenzene and p-nitrochlorobenzene mixture and an o-nitrochlorobenzene product by a rectification method, further converting the m-nitrochlorobenzene and p-nitrochlorobenzene mixture into an m-nitrochlorobenzene and p-nitroanisole mixture by methoxylation reaction, and performing rectification, separation and purification on the mixture to obtain m-nitrochlorobenzene and p-nitroanisole products. The method has the advantages of low energy consumption, short production period and capability of solving the atmospheric pollution problem of a burning treatment method for the nitrochlorobenzene meta-position oil.

The invention relates to a method for preparing o-nitroanisole and p-nitroanisole from mixed nitrochlorobenzene. According to the invention, mixed nitrochlorobenzene consisting of a product obtained after nitration of chlorobenzene, o-nitrochlorobenzene, m-nitrochlorobenzene and p-nitrochlorobenzene is used as a raw material, and in a methanol system, 30% of alkali lye and a phase-transfer catalyst are added for a reaction to prepare products of o-nitroanisole and p-nitroanisole, wherein m-nitrochlorobenzene does not participate in the reaction. The method provided by the invention overcomes the problems of great investment for rectifying tower equipment, great energy consumption in rectification, high cost, long process flow, harsh operation conditions, poor operational safety performances and generation of waste residues hardly to treat in rectification-crystallization separation of mixed nitrochlorobenzene in conventional production processes for o-nitroanisole and p-nitroanisole and overcomes the technical problems of generation of considerable alkaline waste water containing sodium hyposulfite and production of a poor-quality product in a sodium sulfide reduction process.

The invention relates to a method for synthesizing paranitroanisole. The raw materials used by the method are green chemicals dimethyl carbonate (DMC) and p-nitrophenol, and the catalyst is NaY molecular sieve, activated aluminum oxide or activated carbon which is impregnated by alkali metals or alkaline-earth metal compounds. Good conversion rate of the raw materials and good selectivity of target products can be obtained by using the method provided by the invention under the reaction conditions that: the temperature is between 90 and 200 DEG C, and the reaction time is between 1 and 5 hours; the mol ratio of the p-nitrophenol to the dimethyl carbonate of the raw materials is between 1 to 5 and 1 to 15, and the amount of the catalyst is 2 to 20 percent of the mass of the raw materials, wherein, the conversion rate of the p-nitrophenol can reach over 64 percent, and the selectivity of the paranitroanisole can reach 100 percent. The method takes the DMC as a methylated reagent to actually realize a green synthetic route, takes solid alkali as the catalyst, and is superior to the prior synthetic method of homogeneous catalysis or phase-transfer catalysis; and the catalyst is simple to separate and can be reused.

Provided is an electrochemical synthetic method of aminoanisole, belonging to the technical field of electrochemistry. The method needs to be accomplished in a two-chamber electrolysis bath which is separated by employing a cation-exchange membrane, a copper sheet is taken as a negative electrode, a ruthenium net is taken as a positive electrode, a saturated calomel electrode is taken as a reference electrode, the negative electrode and the reference electrode are installed inside a cathode chamber of the electrolysis bath, and the positive electrode is installed inside an anode chamber of the electrolysis bath. Methanol is taken as solvent, sulphuric acid is taken as supporting electrolyte, paranitroanisole is taken as electrolytic reaction substrate, the solvent and the solution of supporting electrolyte are injected into the cathode chamber and the anode chamber, and the electrolytic reaction substrate is injected into the cathode chamber. The electrolyzation is performed within a condition of normal temperature and pressure and a condition that the negative electrode is added with a certain constant voltage relative to the reference electrode, and the constant voltage is between -0.4 to -0.6 V. After the electrolyzation is finished, the electrolyte is post-processed to obtain the product of paraphenetidine with the production ratio between 24.5-63.3%. The method has the advantages of simple requirement, mild reaction conditions, easy preparation of the electrodes, low price, small pollution in the process of reaction and the like, and is a greening production line.

The invention provides a microminiature rapid charging special-purpose aluminium electrolytic capacitor which comprises a shell, a core bag and a rubber plug. The core bag is sealed in the shell through the rubber plug. The core bag contains electrolyte which comprises a solvent, an inorganic acid ammonium salt, an organic acid ammonium salt, and a hydrogen elimination agent. The inorganic acid ammonium salt is ammonium borate or ammonium pentaborate or the mixture of the ammonium borate or the ammonium pentaborate. The organic acid ammonium salt comprises one or more of ammonium sebacate, ammonium azelate, diammonium phthalate, and dodecyl ammonium carboxylate. The hydrogen elimination agent comprises one or more of a p-Nitrobenzyl alcohol, a p nitroanisole and p-nitrobenzoic acid. The conductivity of the electrolyte in the invention is between 2.4 ms/cm to 2.8ms/cm, the ESR value of a product can be effectively reduced, thus the ripple resistance and lightning strike resistance ability of the product are improved greatly, the flash fire voltage is above 490V, in a condition of high voltage, the breakdown of electrolytic paper caused by flash fire of the electrolyte does not appears, and thus the voltageproof performance of the product is ensured.

The invention provides a clean production method of paranitroanisole. The method comprises the step that sodium hydroxide, para-nitrochlorobenzene and methanol react to produce the paranitroanisole, and the reaction refers to that a sodium hydroxide methanol solution is added to a para-nitrochlorobenzene methanol solution in batches under gradient temperature rise. Besides, the clean production method further comprises the step of treatment of a reaction product mixture: the reaction product mixture is distilled, water is added to a reaction kettle after distillation for washing, standing and layering, and the paranitroanisole is obtained from an organic phase. With the adoption of the method, on the premises that side products are turned into wealth and TOC in wastewater is treated to be lower than 20, the yield of the paranitroanisole can be significantly increased and can be higher than 96% particularly.

The invention relates to a method of preparing o-anisidine and p-anisidine through hydrogenation reduction of a mixture of o-nitroanisole and p-nitroanisole. According to the method, o-nitroanisole and p-nitroanisole are used as raw materials, and o-anisidine and p-anisidine are prepared in a methanol system through hydrogenation reduction with Pt/C as a catalyst. With the method provided by the invention, the disadvantages of high energy consumption and high cost in conventional production process of o-anisidine and p-anisidine are overcome, and the technical problems of severe environmental pollution and loss of materials caused by considerable process waste water generated in the process of pretreatment in conventional production process are overcome; the method provided by the invention has the advantages of easiness, a high conversion rate, clean, green and environment-friendly process and a small amount of pollution by three wastes.

The invention relates a method for preparing p-anisidine through catalytic hydrogenation by an industrial-scale device. The method comprises the following steps: adding a raw material namely p-nitroanisole in an industrial-scale hydrogenation kettle in each production cycle in a continuous mode or an intermittent mode, and monitoring the concentrations of the raw material and impurities in the hydrogenation kettle in a reaction process in real time so as to obtain p-anisidine with the purity of 99.5% or above and yield of 100%. The purity of the p-anisidine product obtained through the method reaches 99.5% or above, so that p-anisidine can be directly used and sold; p-anisidine can further be subjected to rectification treatment to obtain a high-quality p-anisidine product with the purity of 99.9% or above which can be used in special fields.

The invention discloses a method for detecting the residual quantity of aminoanisole and paranitroanisole in soil and belongs to the field of analysis and detection. The method comprises the steps of sample preparation, thermal desorption-gas chromatograph-mass spectrometer measurement, and external standard method quantification. The method is suitable for measuring the residual quantity of aminoanisole and paranitroanisole in soil and is simple, convenient to use and environmentally friendly, detection limit is low, and accuracy is high.

The invention discloses a synthesis method of 2-amino-4-acetamino anisole. The synthesis method comprises the following steps: (1) carrying out a primary catalytic hydrogenation reduction reaction onp-nitroanisole and hydrogen in the presence of a catalyst A to obtain p-methoxyaniline; (2) carrying out an acetylation reaction on the p-methoxyaniline to obtain p-acetanisidine; (3) carrying out a nitration reaction on the p-acetanisidine to obtain 2-nitro-4-acetamino anisole; and (4) carrying out a secondary catalytic hydrogenation reduction reaction on the 2-nitro-4-acetamino anisole and hydrogen in the presence of a catalyst B to obtain 2-amino-4-acetamino anisole. 2-amino-4-acetamino anisole is synthesized by using a method sequentially comprising acylation, nitration and reduction, so that the problems that raw materials are easily oxidized, the amount of side reactions is large and a product is difficult to separate and low in purity in a traditional directional acylation process are avoided; and the purity of the product synthesized by using the method disclosed by the invention can reach 99.5%-99.8%.

The invention relates to a synthetic method of p-nitroanisole, which can effectively reduce the generation of by-products, avoid the refining process of the by-product p-nitrophenol and greatly improve the yield of p-nitroanisole; besides, a small amount of p-nitrophenol can be further reused in the synthetic steps of the invention in the subsequent wastewater treatment process. In addition, the p-nitroanisole obtained by the method disclosed by the invention has higher product quality.

The present invention aims to provide a highly reliable aluminum electrolytic capacitor which has no flash points and shows little change or degradation in external appearance and properties. The electrolytic capacitor of the invention comprises a capacitor as an electrode using an aluminum foil, a driving electrolyte having a water content of 20-90wt%, a bottom barrel type house of the capacitor receiving the driving electrolyte, and a sealing material which seals an opening part of the house. The driving electrolyte contains one or more nitro compound of 0.01% by weight selected from p-nitrophenol, m-nitrophenol, o-nitrophenol, p-nitrobenzoic acid, m-nitrobenzoic acid, o-nitrobenzoic acid, p-nitroanisole, m-dinitroanisole, p-dinitroanisole. The freezing point of the electrolytic solution is under -10 DEG C, the chlorine content of the sealing material is less than 300ppm to the weight of the sealing material.

A crystallizing process for separation of nitro phenylmether mixture includes such steps as thermal dissolving of said mixture in methanol, decoloring, removing impurities, filtering to obtain refined liquid, cooling step by step for crystallizing, filtering to obtain p-nitro phenylmether and o-nitro phenylmether, respectively recrystallizing in methol, separation and refining to obtain refined two products.

The invention discloses a method for preparing p-aminoanisole by catalytic hydrogenation, and belongs to the technical field of catalytic hydrogenation. A p-nitroanisole solution is taken as a raw material, catalytic hydrogenation reaction is carried out in a trickle bed reactor by using a supported metallic nickel catalyst under a hydrogen atmosphere of 313-343 K and 1.0-2.0 MPa, on-line operation lasts for more than 4500 h, the conversion rate of the p-nitroanisole is greater than 99%, and the selectivity of the p-aminoanisole is greater than 99%.

The invention discloses a preparation method of an Iguratimod intermediate, which comprises the following steps: by taking p-nitroanisole as a raw material, carrying out substitution nucleophilic substitution (VNS) on p-nitroanisole and methoxyamine hydrochloride in the presence of a copper salt catalyst and an acid-binding agent to generate 5-methoxy-2-nitroaniline (compound II); the synthesis method comprises the following steps: carrying out a nucleophilic substitution reaction on 5-methoxy-2-nitroaniline (compound II) and methanesulfonyl chloride to generate a compound III, etherifying the compound III and phenol under the catalysis of a copper salt to generate N-(5-methoxy-2-phenoxy phenyl) methane sulfonamide (compound IV), and reagents used in the synthesis process are non-highly toxic products and are easy to obtain; no iron powder is used in the reaction process, so that iron mud which is harmful to the environment is not generated, and the environmental protection property is high; the reaction operation difficulty is small, the safety is high, and a foundation is laid for industrial preparation of Iguratimod drugs.

The invention provides a preparation method of 4-(trifluoromethylthio)nitrobenzene, which is implemented by reacting paranitroanisole with trifluoro-methanthiol at a temperature of 60-150 DEG C, so that 4-(trifluoromethylthio)nitrobenzene is obtained. According to the invention, products are prepared by adopting a new synthetic method, especially by taking new raw materials through a one-step process, the whole production process is normally operated, reaction conditions are mild, and the utilization of anhydrous hydrogen fluoride with large toxicity and corrosivity is effectively avoided, therefore, the method has a broad application prospect.

The invention discloses a preparation method of P-aminoanisole. The p-aminoanisole is obtained through performing continuous catalytic hydrogenation on paranitroanisole and then sedimentation and membrane filtration. The preparation method disclosed by the invention can achieve the effects of high production efficiency, high product quality, low labor intensity, environmental friendliness, high catalyst utilization rate and beneficial industrialization.

The invention provides a preparation method of N-methyl-4-methoxyaniline. The method comprises the following steps: mixing p-nitroanisole, paraformaldehyde and a catalyst, and carrying out a reductionreaction in a hydrogen atmosphere to obtain the N-methyl- 4-methoxyaniline. The preparation method provided by the invention is few in steps, simple to operate, mild in conditions, stable in catalystperformance and low in cost. No solvent is required, and the separation difficulty of a product is reduced. According to the description of embodiments, the product yield of the preparation method is86% or more than 86 %.

The invention provides a preparation method of p-anisidine, and belongs to the technical field of chemical synthesis. The method comprises the following steps: firstly, adding a predetermined amount of methanol and a catalyst into a hydrogenation kettle, replacing, removing oxygen and activating the catalyst, and dropwise adding a raw material p-nitroanisole into the hydrogenation kettle at a predetermined hydrogen pressure and a predetermined reaction temperature to carry out a hydrogenation reaction. According to the method, in the process of reducing the use amount of methanol and dropwise adding p-nitroanisole for hydrogenation reaction, the concentration of p-nitroanisole in a hydrogenation kettle is always kept at a lower level, the solvent and the catalyst are sufficient, p-aminoanisole which is continuously generated is utilized to play a role of the solvent, the substrate reaction is more thorough, the reaction time is greatly shortened, and the generation amount of byproducts is reduced. Experiments show that the single-kettle hydrogenation reaction time is shortened by 30%-47%, the single-kettle productivity can be improved by 33%-97%, meanwhile, the single-kettle reaction time is shortened, the daily productivity can be improved by 77%-125%, and the purity of p-anisidine in the product reaches 99.3%-99.7%.