24results about "Nitro compound preparation" patented technology

The application discloses a preparation method of a modified mordenite catalyst, the catalyst prepared by the method, and application of the catalyst. The preparation method comprises the following steps: 1) adding mordenite into acid, soaking, and roasting to obtain acid-modified mordenite; 2) fully contacting the acid-modified mordenite with TiCl4 vapor to obtain Ti-modified titanium mordenite; 3) mixing the Ti-modified titanium mordenite with tungsten metal salt, zirconium metal salt and molybdenum metal salt in a solution, adding ammonia water to age, filtering out solid, and washing, drying and roasting the solid to obtain a supported catalyst; and 4) immersing the obtained supported catalyst in acid, filtering and roasting to obtain the modified mordenite catalyst. The modified mordenite catalyst has high catalytic activity for catalytic nitration of aromatic hydrocarbons, high product yield, reusability and long service life.

A process and a system to produce sustainable, especially renewable diisocyanates as well as downstream products 5 thereof are provided.

The invention relates to a process for producing nitrobenzene by an adiabatic nitration of benzene (2) and nitric acid (1) in the presence of sulfuric acid (7), the process comprising: (a) feeding benzene (2), nitric acid (1) and sulfuric acid (7) into a reaction zone (R); (b) producing a reaction mixture (4) comprising water, nitrobenzene and sulfuric acid by reaction of the benzene and the nitric acid in the presence of the sulfuric acid in the reaction zone (R); and (c) separating the reaction mixture into an aqueous phase (6) comprising water and sulfuric acid and an organic phase (5) comprising crude nitrobenzene by phase separation; wherein the concentration of titanium in the reaction mixture (4) is kept below 170 mg / kg.

A method of making 4-fluoro-3-methoxyaniline includes reducing 1-bromo-5-fluoro-4-methoxy-2-nitrobenzene using a catalyst, which produces an increased yield.

The application relates to the technical field of catalytic materials, and relates to an organic photocatalytic material and a preparation method thereof.1, comprising the following steps: mixing modified N-hydroxy phthalimide phenylacetate, an aliphatic nitroalkane, 2,6-dimethylpyridine, a photocatalyst and a solvent, then irradiating under visible light, placing in an inert atmosphere, stirring for 2-8 hours, and obtaining a product through post-treatment to obtain a final product; the mass ratio of the modified N-hydroxy phthalimide phenylacetate, the nitro compound, the 2,6-dimethylpyridine, the photocatalyst and the solvent is 2-5:1-2:1-3:1:8-11. The visible light catalysis method can be used to synthesize the nitro compound under mild conditions, and further provides a green and efficient new path for the preparation of a nitrogen-containing drug intermediate.

The application provides a preparation method of an exatecan intermediate and application thereof. Specifically, 3-fluoro-4-methyl-8-oxo-5,6,7,8-tetrahydronaphthalene acid solution is converted into 1-nitro-3-fluoro-4-methyl-8-oxo-5,6,7,8-tetrahydronaphthalene by a nitration reaction with mixed acid in a micro-channel reactor, the method has high reaction efficiency, less nitric acid consumption, reduces waste liquid discharge, and has short reaction time, and greatly improves reaction safety. The application also provides a preparation method of exatecan comprising the method. The method adopts a brand-new design route, starting materials are easier to obtain, and a reaction route is shorter, compared with the prior art, the total yield of exatecan is significantly improved.

The invention provides a deuterated methylamine hydrochloride green synthesis method based on a continuous flow technology, which seamlessly integrates photocatalytic nitrification, catalytic hydrogenation and online acidification salification into a continuous and compact technological process through the continuous flow technology. And one-stop continuous synthesis from a gaseous raw material to a high-purity product is realized under a mild condition. Inert C-D bonds in deuterated methane can be efficiently activated at near room temperature in the core photocatalytic nitration step, and compared with a traditional high-temperature and high-pressure process, energy consumption is greatly reduced; the deuterated methane is used as a raw material, the use of a highly toxic reagent is avoided from the source, a continuous flow reaction system is combined with integrated water electrolysis for hydrogen production, the liquid holdup is small, and the intrinsic safety is high; meanwhile, a new way is provided for high-value utilization of deuterated methane, and the iron-based photocatalyst is low in cost and environmentally friendly and has good recycling potential.

The present invention discloses a continuous process for amination of aminopyridines. Particularly, the invention provides a two-step or multi-step process comprising a first continuous nitration step followed by a continuous hydrogenation step to introduce an amino group to an 2-aminopyridine in meta position. Such diaminopyridine compounds are valuable starting materials in the manufacture of active pharmaceutical ingredients.

This invention discloses a method for purifying toluene and its application. The method includes: catalytic conversion of toluene using a porous metal catalyst in an acidic environment below 60°C; and then mixing the converted liquid with an alkaline solution for separation to obtain purified toluene. This method converts non-aromatic hydrocarbons and C8 / C9 aromatic hydrocarbons in toluene into smaller molecules or acidic substances, which are then removed by alkaline washing. When toluene is used in nitration reactions, it reduces the content of fatty acids and benzoic acids during the nitration process, preventing non-aromatic hydrocarbons and C8 / C9 aromatic hydrocarbons from converting into carboxylic acid emulsion impurities during nitration, thus reducing the risk of emulsification in the nitration reaction.

The application discloses a kind of magnolol amide compounds and its preparation method and antibacterial application.The compound is with magnolol as parent nucleus, structure is modified by introducing different substituted amide side chain and is obtained, and its structure is as shown in general formula (I).The magnolol amide compound can be used to prepare antibacterial drugs, especially can be used to prepare anti-staphylococcus aureus, methicillin-resistant staphylococcus aureus, biofilm-related infection treatment drug and polymyxin antibiotic sensitizer.Therefore, the magnolol amide compound has good application prospect as antibacterial drug or antibacterial adjuvant further development, while yield is higher, synthesis method is simple, easy to obtain, suitable for amplification production, and is expected to be further developed as clinical natural product antibacterial drug.(I)

The present invention relates to a process for concentrating dilute sulfuric acid (10) which can contain at least one nitroaromatic compound and / or nitric acid as impurities, comprising: (a) feeding the dilute sulfuric acid (10) to a first stage (1) in which low boilers are removed by evaporation and / or stripping to obtain a first concentrated sulfuric acid (12); (b) optionally feeding the first concentrated sulfuric acid (12) to a second evaporation stage (2) to obtain a second concentrated sulfuric acid (14); (c) if step (b) is carried out, feeding the second concentrated sulfuric acid (14) to a third evaporation stage (3), or if step (b) is not carried out, feeding the first concentrated sulfuric acid (12) to a third evaporation stage (3) to obtain as product concentrated sulfuric acid (16), wherein an oxidizing agent (17) and / or a precursor of an oxidizing agent is fed to the third evaporation stage (3).

The application provides a deuterated nitromethane synthesis method based on a continuous flow photocatalysis technology. The method uses deuterated methane obtained in a Fischer-Tropsch synthesis or an electrocatalytic reduction of CO2 as a raw material, and realizes direct nitration in a continuous flow microreactor under the joint action of an iron-based photocatalyst and specific wavelength light. The reaction effectively inhibits side reactions such as over-nitration, so that the selectivity of the deuterated nitromethane reaches more than 90%, and the product has high purity. The method uses an iron-based photocatalytic system to realize direct nitration of deuterated methane under ultraviolet light and / or visible light irradiation, has the advantages of safe and reliable process, recyclable use and the like, and is suitable for industrial production.

This invention provides a reaction apparatus and a method for preparing 2,2-dinitropropanol. The preparation method includes the following steps: Nitroethane reacts with an alkaline solution in a series of sequential sub-static tubular reactors to obtain a dehydrogenation system; the dehydrogenation system reacts with an aqueous formaldehyde solution to obtain a hydroxymethylation intermediate system; the hydroxymethylation intermediate system reacts with a sodium nitrite solution to obtain a nitrosation intermediate system; the nitrosation intermediate system reacts with an aqueous sodium persulfate solution and an aqueous potassium ferricyanide solution to obtain a partially oxidized intermediate system; the partially oxidized intermediate system is then transferred to a dynamic tubular reactor for further oxidation to generate 2,2-dinitropropanol. This invention solves the problems of uncontrollable exothermic reactions, solid impurities causing pipeline blockage during oxidation, and high costs and environmental pollution due to excessive reliance on solvent dilution in existing 2,2-dinitropropanol preparation processes.

The application discloses a preparation method of 1,2,3-trichloro-4,6-dinitrobenzene, which comprises the following steps: (1) sulfuric acid and 1,2,3-trichlorobenzene are sequentially added into a batching kettle, mixed uniformly and heated to 60-75 DEG C to obtain a mixture A; (2) nitric acid and sulfuric acid are sequentially added into another batching kettle and mixed uniformly to obtain a nitrosulfur mixed acid; (3) two feed modes are adopted, the mixture A obtained in the step (1) and the nitrosulfur mixed acid obtained in the step (2) are pumped into a two-stage tubular reactor with a diameter of 10 mm respectively to carry out nitration reaction; (4) after the nitration reaction is completed, the reaction liquid obtained in the two-stage tubular reactor is transported into a receiving tank, waste acid and an organic phase are separated, the residual waste acid in the organic phase is neutralized and washed to neutral to obtain 1,2,3-trichloro-4,6-dinitrobenzene. According to the application, the conversion rate of the 1,2,3-trichlorobenzene is greater than 99%, the yield of the obtained product 1,2,3-trichloro-4,6-dinitrobenzene is greater than 98%, and the purity is greater than 99.5%.

The application provides a continuous flow synthesis method of 4,6-diaminoresorcinol salt and belongs to the technical field of chemical synthesis. The continuous flow synthesis route of acetyl-protected phenolic hydroxyl-nitration-nitro reduction and simultaneous deacetylation-acidification is used to synthesize 4,6-diaminoresorcinol salt through automatic control. The whole reaction process is carried out in a closed environment, and the reaction safety and the reaction efficiency are improved. The application controls the dosage, the pumping speed, the reaction time and the reaction temperature and other conditions of each reactant, so that the synthesized 4,6-diaminoresorcinol salt has high purity and high yield. The purity and the yield of the product can reach 99.9% and 85.0% respectively, and the application has a wide application prospect in continuous flow industrial production.

Processes and systems for producing isomeric mixtures of aromatic amine monomers from aromatic feeds. An example process for producing isomeric mixtures of aromatic amine monomers from aromatic feeds may include nitrating at least a portion of an aromatic feed to produce a mixture of nitrated aromatic compounds. The example process may further include hydrogenating at least a portion of the nitrated aromatic compounds to produce an isomeric mixture of aromatic amine monomers. The example process may further include processing the isomeric mixture of aromatic amine monomers to form a product selected from an aromatic compound with a different functional group than the aromatic amine monomers, a polymerized product, or a reaction product of the aromatic amine monomers and H2S.

This invention provides a green synthesis method for methane to methylamine hydrochloride based on continuous flow technology. Using methane as a raw material, this method integrates photocatalytic nitration, catalytic hydrogenation, and online salt formation in a continuous flow reaction system. Through the pathway of "methane → nitromethane → methylamine hydrochloride," high-purity methylamine hydrochloride is continuously prepared from gaseous feedstock. In this invention, the photocatalytic nitration step uses an iron-based photocatalyst, which can efficiently activate the C-H bonds of methane under mild conditions. This method has advantages such as mild conditions, low energy consumption, high selectivity, intrinsic safety, and low catalyst cost, providing a new green pathway for the high-value utilization of methane.

The application discloses a preparation method of p-nitrotoluene and relates to the technical field of organic synthesis, and comprises the following steps: S1, liquid CO2 is filled into a high-pressure reaction kettle, and then toluene, mixed acid and a solid acid catalyst are sequentially added to perform a nitration reaction; wherein the mixed acid is prepared from nitric acid and concentrated sulfuric acid; S2, organic phase after the nitration reaction is separated; S3, the organic phase is sequentially washed and dried to obtain a high-selectivity p-nitrotoluene product. The preparation method of the p-nitrotoluene uses liquid CO2 as a reaction medium, and toluene is subjected to a nitration reaction with the mixed acid as a nitration agent under the action of a solid acid catalyst, and the para-position selectivity of the reaction can be improved by controlling the reaction conditions.

The application belongs to the field of organic chemical synthesis, and particularly relates to a preparation method of imino aryl compounds and intermediates. The preparation of the intermediate IX comprises the following steps: obtaining compound IX through a reduction reaction of compound VIII, and the reaction formula is as follows: the imino aryl compound is obtained through subsequent reactions of the intermediate compound IX. The preparation method has the advantages of high yield, high product purity and easy industrial production.

The utility model discloses a p - nitrochlorobenzene nitration reactor, specifically relates to the technical field of nitration reactor, including the reaction kettle shell, the bottom fixedly connected with support leg of reaction kettle shell, the bottom fixedly connected with the bottom plate of support leg, the top fixedly connected with the cover of reaction kettle shell, the top of cover is provided with the feeding opening, the inside of reaction kettle shell is provided with the inner bag, the inside of inner bag is provided with the stirring rod, and the top of cover is installed the motor of drive stirring rod rotation. The utility model discloses through setting up the multilayer type shock pad of assemblable clamping structure, can effectively when the reactor use to the vibration that produces plays good shock attenuation effect, reduces the vibration influence to the placement surface, and convenient in use to the heat release of p - nitrochlorobenzene nitration reaction process carries out the circulating heat exchange cooling treatment, avoids the problem that the air pressure change caused by the big temperature difference inside and outside causes the inner bag or the reaction kettle shell to take place the bulge of the air pressure change.

The application belongs to the field of synthesis of organic high-energy compounds, and particularly relates to two novel polynitro-pyrene energetic compounds and a synthesis method and application thereof. The two novel polynitro-pyrene energetic compounds are 1,2,3,6,8-pentanitro-pyrene (PNP) and 1,2,3,6,7,8-hexanitro-pyrene (HNP) respectively. The synthesis method is to use pyrene as a starting material, and to react with a nitration reagent under heating conditions to efficiently synthesize PNP and HNP in one step. PNP and HNP have significant application potential as high-energy explosives or energetic components. In addition, the polynitro-pyrene energetic molecules can also be applied to lithium primary batteries as positive active materials. The theoretical specific capacity of PNP and HNP is up to 1883 mAh g ‑1 and 2044 mAh g ‑1 , which is the highest level of all reported primary battery positive materials.

The application discloses a kind of organic total synthesis methods of nimesulide derivatives, it is obtained by the reaction of phenol derivative and nitration test, first intermediate;First intermediate and esterification reagent are esterified, and second intermediate is obtained;Second intermediate and nucleophilic reagent are substituted, and third intermediate is obtained;Third intermediate and phenol derivative are coupled, and fourth intermediate is obtained;Fourth intermediate and reducing agent are reduced, and fifth intermediate is obtained;Fifth intermediate and sulfonylation reagent are sulfonylated, and sixth intermediate is obtained;Sixth intermediate and nitration reagent are nitrified, and nimesulide derivative is obtained.The application selects more easily preserved, cheap and easily obtained and higher safety substrate and reagent, process is simple, reaction condition requirement is low, green environmental protection, safety performance is good, product yield is high, easy to scale production.

The present application relates to a kind of preparation method of fluorine-containing nitro aromatic ether, specifically to a kind of preparation method of 1,2-difluoro-4-methoxy-5-nitrobenzene, belong to fluorine-containing fine chemical intermediates preparation technical field.The present application is 3,4-difluorophenol as raw material, under the action of Lewis acid catalyst, with iron nitrate nonahydrate reaction, 4,5-difluoro-2-nitrophenol is generated;Subsequently again with dimethyl sulfate is methylated, and 1,2-difluoro-4-methoxy-5-nitrobenzene is obtained.The nitration system of tri (pentafluorophenyl) boron and iron nitrate nonahydrate is used in the present application, can greatly improve the position selectivity of nitration reaction (preferentially attack 6-position), significantly inhibit nitration side reaction, easy to operate safely, reaction condition is mild, without low temperature or strong corrosive environment, easy to industrialization scale production.