151results about "Nitro compound preparation" patented technology

The invention discloses a synthesis method of 2, 4, 5-trifluorophenylacetic acid, which comprises the following steps: by taking cheap and easily available o-chloronitrobenzene as a raw material, reacting with sodium nitrate in a sulfuric acid and trifluoroacetic acid system, separating generated 2, 4-dinitrochlorobenzene through melt crystallization, and continuing to synthesize 2, 4-dinitrochlorobenzene in methyl chloroacetate to obtain 2, 4, 5-trifluorophenylacetic acid. The method comprises the following steps: carrying out indirect aromatic nucleophilic substitution reaction on 2, 4-dinitrophenylacetic acid under the condition of sodium hydride to generate 5-chloro-2, 4-dinitrophenylacetic acid methyl ester, separating, carrying out fluorination reaction on the 5-chloro-2, 4-dinitrophenylacetic acid methyl ester and potassium fluoride under the action of a phase transfer catalyst, carrying out rectification separation to obtain 2, 4, 5-trifluorophenylacetic acid, and carrying out hydrolytic acidification on the 2, 4, 5-trifluorophenylacetic acid in a sodium hydroxide aqueous solution to obtain 2, 4, 5-trifluorophenylacetic acid. And the process route is safer, more environment-friendly, more efficient and lower in cost.

The invention discloses a continuous kettle type nitromethane production process, and relates to the technical field of basic chemical raw material synthesis and flow chemical reaction process control, which comprises the following steps: quantitatively and continuously pumping a temperature-regulated sodium nitrite mixed solution into a raw material mixer in a closed-loop automatic control mode through a variable-frequency feeding pump matched with a mass flow meter; synchronously, quantitatively and continuously pumping dimethyl sulfate into the raw material mixer in a closed-loop automatic control manner by matching a feeding pump with a stop valve and a mass flow meter, and uniformly mixing the two raw materials in the raw material mixer according to the stoichiometric molar ratio of the dimethyl sulfate to the sodium nitrite, according to the tandem type segmented design, each reaction kettle can be subjected to customized temperature field control and heat transfer design specially aiming at the special thermodynamic and dynamic requirements of the reaction stage where the reaction kettle is located, the heat transfer efficiency of the whole system is greatly improved, and due to the fact that reaction heat is taken away timely and accurately, the heat transfer efficiency is greatly improved. And a by-product generation path induced by local abnormal high temperature is effectively restrained.

The utility model belongs to the technical field of nitration machines, and discloses a reactor internal structure for continuous nitration of dinitrotoluene, which comprises a heat exchange cylinder body which is a main body structure of a heat exchange device and is internally provided with a guide cylinder, and the guide cylinder is fixed between an upper tube plate and a lower tube plate and placed in the center of a stirring container. And the interior of the machine is divided into a stirring area with a stirrer and a circulating area which cannot be directly stirred by the stirrer. The baffle is arranged in the guide cylinder, so that the stirring strength can be increased by about 25%, and the reaction speed can be increased. The length of the baffle is consistent with that of the guide cylinder, but the baffle is not arranged at the stirring blade, a radial baffle is additionally arranged above the guide cylinder and below the liquid level, the radial baffle is connected with the machine wall to reduce the vortex of the liquid, and the baffle is welded with the baffle of the guide cylinder. The baffle plates are arranged in the heat exchange barrel and used for supporting the heat exchange tubes, relieving the stress condition of the heat exchange tubes, preventing fluid flowing from causing vibration of the heat exchange tubes, prolonging the length of a medium flow channel and improving the heat transfer efficiency.

The application provides a method for continuously preparing nitrobenzene by using benzene and NO2 as raw materials. The method is characterized in that: a solid catalyst capable of catalyzing the nitration of benzene by NO2 is filled in a pipe reactor, benzene, NO2 and O2 are continuously fed into the pipe reactor at a certain flow rate, and the reaction is carried out at a certain temperature to obtain nitrobenzene. This route is safe, green, economical and efficient, and is a safe, green, economical and efficient nitrobenzene synthesis route.

The invention relates to the field of chemical equipment, in particular to a 1-nitroanthraquinone continuous production process based on a dynamic liquid membrane continuous flow reactor, which comprises a solid feeding device, a homogeneous emulsifier, a quenching kettle, a solid-liquid separator, a centrifugal separator and a dynamic liquid membrane reactor, a sulfuric acid storage tank is divided into two branches through a sulfuric acid feeding pump, one branch is connected to the dynamic liquid membrane reactor, the other branch is connected to the dynamic liquid membrane reactor through a flow self-control valve, the quenching kettle is connected to a solid-liquid separator, the solid-liquid separator is divided into two branches, one branch is connected to an anthraquinone crude product storage tank, the other branch is connected to a centrifugal separator, and the other branch is connected to a gas-liquid separator. The centrifugal separator is divided into two branches, one branch is connected to the acid water storage tank, and the other branch is connected to the dichloroethane storage tank, so that the reaction selectivity of the anthraquinone nitration reaction can be effectively improved, high-viscosity solids are prevented from being blocked, and the conversion rate of raw materials in the continuous reaction of the anthraquinone nitration reaction is improved.

The invention discloses a method for preparing nitro-mesitylene through a micro-channel nitration reaction. The method comprises the following steps: respectively conveying mesitylene, fuming nitric acid and sulfuric acid to a micro-channel reaction module through a metering pump, and completing nitration reaction within a retention time of tens of seconds to several minutes. The introduction sequence of nitration reaction materials, the reaction retention time and the reaction temperature are cooperatively controlled, the nitration reaction is completed in the microchannel reactor in a continuous flow mode, operation is easy and convenient, safety is high, efficient continuous production can be achieved, meanwhile, emission of three wastes is reduced, and the industrial application advantages of being environmentally friendly and economical are achieved.

A green synthesis method of nitrobenzene compounds, in an organic solvent, using aromatic amine as raw material, using an oxidant and a catalyst to form a reaction system, selectively oxidizing aromatic amine into corresponding nitrobenzene compounds, the method selects an oxidant which is green, pollution-free, the catalyst is common, easy to obtain, low in price, and has significant catalytic effect, and the reaction conditions are mild, simple in operation, low in cost, fast in speed, high in selectivity and high in product yield, which is a novel, good scientific research value and industrialization potential synthesis method of nitrobenzene compounds.

The invention discloses a preparation method of Linzagolix, which comprises the following steps: taking 2, 3-difluoro-6-methoxybenzyl alcohol as a raw material, under the action of alkali and phosphine ligand, carrying out Mitsunobu reaction on 2, 3-difluoro-6-methoxybenzyl alcohol and 2-methoxy-4-fluorophenol to obtain a compound A, sequentially carrying out nitration reaction and reduction reaction on the compound A to obtain a compound C, and carrying out recrystallization on the compound C to obtain the Linzagolix. Under the alkaline condition and the action of triphosgene, the compound C and 4-aminothiophene-2, 3-dimethyl dicarboxylate hydrochloride are subjected to a one-pot condensation reaction to obtain a compound D, and the compound D reacts under the alkaline condition to generate Linzaolix. According to the invention, the synthesis process of Linazagolix is shortened to five steps, the reaction condition is mild, the operation is simpler and more convenient, and the method is suitable for industrial production.

The invention provides a production method and production equipment of an aromatic nitro compound, and the production method comprises the following steps: carrying out nitration reaction on fuming nitric acid, a sulfuric acid-nitric acid mixed solution and aromatic hydrocarbon to obtain a nitration product crude product and waste acid; performing first-stage pickling on the nitration product crude product by using first pickling water to obtain a first-stage pickled crude product and first-stage yellow water; performing second-stage pickling on the first-stage pickling crude product by adopting second pickling water to obtain a second-stage pickling crude product and second-stage yellow water; mixing the first-grade yellow water with a nitric acid replenishing solution to obtain a sulfuric acid-nitric acid mixed solution, and returning the sulfuric acid-nitric acid mixed solution to the nitration reaction as a raw material; the second pickling water is concentrated wastewater generated by concentrating a byproduct dilute sulfuric acid in the preparation process of fuming nitric acid to form concentrated sulfuric acid; the first pickling water is a mixed solution formed by mixing secondary yellow water and sulfuric acid. The production method is good in operation stability, simple in technological process and low in cost.

The invention belongs to the technical field of deuterated organic chemical synthesis, and particularly relates to a synthetic method of deuterated m-dibromobenzene-D4, which comprises the following steps: a, nitration reaction of deuterated benzene: enabling the deuterated benzene to react with mixed acid to generate deuterated nitrobenzene; b, performing bromination reaction on the deuterated nitrobenzene: reacting the deuterated nitrobenzene with liquid bromine by taking iron tribromide as a catalyst to generate deuterated m-bromo nitrobenzene; c, carrying out reduction reaction on the deuterated m-bromonitrobenzene: converting the deuterated m-bromonitrobenzene into deuterated m-bromoaniline by taking biboric acid as a reducing agent; and d, diazotization reaction of the deuterated m-bromoaniline: enabling the deuterated m-bromoaniline to react with cuprous bromide to generate the target product deuterated m-dibromobenzene. The deuterated m-dibromobenzene-D4 product with high purity and deuterated rate is prepared by the synthetic method, the process is simple, the raw materials are low in price and easy to obtain, and the application of the deuterated halogenated aromatic hydrocarbon serving as an intermediate in synthesis in the fields of organic photoelectricity and deuterated medicines is expanded.

The present application relates to a kind of raw material benzene p-nitrobenzene hydrogenation catalyst influence evaluation method, comprising the following steps: raw material benzene is purchased, and heavy component monitoring index is increased, and heavy component is directly used in nitration and hydrogenation process when lower than certain content;Heavy component is higher than certain content, and raw material benzene needs to be concentrated, and the influence on hydrogenation catalyst activity is evaluated, and raw material benzene use and processing scheme are formulated according to the evaluation result.The present application also relates to a kind of aniline production method.The present application can effectively prevent the material of entraining toxic catalyst in raw material benzene, along with nitrobenzene into hydrogenation reactor, effectively avoid catalyst activity reduction, cause hydrogenation reaction parameter to fluctuate sharply, and then lead to catalyst consumption sharp increase, when serious, can cause system catalyst overall deactivation, improve the stability of production process.

The present application relates to the technical field of chemical production, and discloses a method and device system for continuously producing nitrochlorobenzene and application thereof. In the method, mixing of reaction raw materials and reaction are completed in steps, so that the defect of too severe heat release, too high temperature, side reaction and safety problem caused by direct reaction is avoided. Meanwhile, by controlling the volume flow ratio of nitric acid and chlorobenzene feed, the raw material conversion rate and the yield of the target product are improved, and the proportion of p-nitrochlorobenzene in the product is also increased, so that the economic benefit is improved. In addition, the method provided by the present application does not need concentrated sulfuric acid as a catalyst, so that the problem of difficult treatment of waste sulfuric acid is solved, and the environmental protection of nitrochlorobenzene production is improved.

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.

This invention discloses a highly efficient synthesis method for the low-byproduct polymerization inhibitor DNBP, belonging to the field of polymerization inhibitor synthesis technology. The method first prepares PVP-PS / [BMIM]NO3 composite microspheres, then disperses o-sec-butylphenol and the composite microspheres in ethyl acetate, adds 40%~45% nitric acid (molar ratio 1:2.0~2.2), and reacts at 40℃ and 500~700 r / min for 5 h. After post-treatment and crystallization, the product is obtained. The composite microspheres achieve a synergistic effect through PS core thermal conduction temperature control, PVP shell directional enrichment, and [BMIM]NO3 regulating nitric acid release. This solves the problems of high byproducts and low nitric acid utilization in traditional processes, meeting the requirements of clean production.

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

The research aims to optimize the synthesis process of oxyfluorfen, improve the product yield and purity, and turn byproducts into wealth. According to an original process route, resorcinol is used as a starting raw material, and oxyfluorfen is synthesized through double etherification, nitration and ether exchange. After optimization, the total yield reaches 94.1%, and the purity reaches 98.4%. In order to improve the utilization rate of the raw materials, an acidic water phase obtained after quenching of an oxyfluorfen reaction solution is subjected to reduced pressure distillation, the byproduct 3-chloro-4-hydroxy-trifluorotoluene is recovered, and the yield can reach 93.7%. Further serving as a raw material of a new process, and synthesizing a target product through nucleophilic substitution. In the route, 2, 4-dichloronitrobenzene with moderate reaction activity and better selectivity is innovatively used for replacing 2, 4-difluoronitrobenzene, so that side reaction is effectively inhibited, and a target product with the content of 98.7% is obtained at the total yield of 94.8%. According to the new and old combination strategy, through integration of two process routes, high-valued conversion of by-products is realized, limitation of a traditional synthesis method is broken through, and atom economy is remarkably improved.

The application discloses a preparation method of nitrophenol, which comprises the following steps: taking a nitrous acid compound as a nitro source, and reacting the nitrous acid compound with a phenol compound in a solvent under the catalysis of an acyl chloride or an anhydride catalyst to generate the nitrophenol. The application has the advantages of wide application range of substrates, mild reaction condition, short reaction time, simple operation, no use of strong acid and metal catalyst, environmental friendliness, excellent yield, and the like, and the yield can reach 95%.

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.

The invention provides a nitration device and a nitration process of methyl benzoic acid, the nitration device comprises a first spiral reactor, a static tubular mixer and a second spiral reactor which are communicated with one another, a lower discharge port of the second spiral reactor is communicated with a reaction slurry inlet of the first spiral reactor through a circulation pipeline; when the nitration device provided by the invention is used for nitration of methyl benzoic acid, nitration reaction liquid flowing out of the lower discharge hole of the second spiral reactor is pumped into the first spiral reactor through the circulating pump to form forced circulation, and methyl benzoic acid solid powder added by the spiral feeder is quickly dispersed by the circulating nitration reaction liquid; the blockage is avoided, the mass and heat transfer efficiency is improved, the generation of byproducts is reduced, and the continuous, safe and stable production is ensured.

The invention discloses a method for preparing nitroisopropylbenzene through a micro-channel nitration reaction. The method comprises the following steps: diluting isopropylbenzene with an organic solvent to obtain a mixed solution with the mass concentration of isopropylbenzene being 25-38%, respectively conveying the mixed solution and fuming nitric acid as reaction materials into a microchannel reactor through a metering pump, carrying out a mixed reaction, and completing a nitration reaction to prepare the nitroisopropylbenzene. The method is easy and convenient to operate and high in safety, efficient and continuous production can be achieved, only fuming nitric acid is adopted, nitric acid / concentrated sulfuric acid is not needed, generation of waste acid is reduced, the selectivity of the product is obviously improved, the total yield of nitroisopropylbenzene is 87.7%-95%, and the method has the industrial application advantages of being environmentally friendly and economical.

The invention discloses a preparation method of a nitrated beta-diketone extraction agent applied to extraction of lithium from brine with a high sodium-lithium ratio, and relates to a preparation method of a beta-diketone extraction agent applied to extraction of lithium from a system with a high sodium-lithium ratio. The invention aims to solve the technical problems that the existing beta-diketone extraction agent for lithium ions is low in extraction capacity, high in alkali consumption and easy to cause an emulsification phenomenon. According to the method, the beta-diketone extraction agent is obtained through the reaction of the 3-amyl octane-1-alcohol and the diketene, the beta-diketone extraction agent is used for the reaction of the beta-diketone extraction agent and the nitric acid, and the beta-diketone extraction agent is modified to obtain the nitrated beta-diketone extraction agent, so that the chemical stability is remarkably improved, the decomposition resistance and the emulsification resistance are high, and the yield is high. And the lithium ion extraction rate is kept at 90% or above, the solution loss is low, and the operation cost is greatly reduced. The method is particularly suitable for efficiently and selectively recovering lithium from lithium-containing wastewater with complex components, especially high-sodium background, and solves the problem of low product purity in a traditional method.

The invention belongs to the field of organic chemical synthesis, and particularly relates to a preparation method of imino aryl compounds and intermediates. The preparation method of the intermediate comprises the following steps: carrying out selective dechlorination reaction on a compound III to obtain a compound IV, wherein the reaction formula is shown in the specification; and carrying out subsequent reaction on the intermediate compound IV to obtain the imino aryl compound. The preparation method disclosed by the invention has the advantages of high yield, high product purity and easiness in industrial production.

The invention belongs to the technical field of organic synthesis and fine chemical engineering, and particularly relates to a method for continuously synthesizing 2, 5-dimethoxy-4-nitrochlorobenzene. A continuous flow reaction system is adopted, 2, 5-dimethoxychlorobenzene and 75%-78% nitric acid are pumped into the system respectively, mixed and then enter a silicon carbide microchannel reactor, an initial reaction is carried out at the temperature of 40-60 DEG C, then the mixture enters a coil delay microreactor at the temperature of 50-70 DEG C to complete nitration, and the total retention time is 20-80 seconds. According to the method disclosed by the invention, accurate temperature control on the strong exothermic nitration reaction is realized through enhanced mixing and heat transfer of the microreactor, concentrated sulfuric acid does not need to be added, the reaction can be completed within tens of seconds, the raw material conversion rate is high (the residue is less than or equal to 0.13%), the product selectivity is good (the content is more than or equal to 98.33%), and the production efficiency and the process safety are remarkably improved; the method is suitable for green, efficient and continuous production of the intermediate, realizes accurate monitoring, and is suitable for large-scale safe production.

The present invention relates to a process for providing halogenated 5,6-difluoro-2- methoxybenzenamine and 4,5,6-trifluoro-2-methoxybenzenamine. Further it relates to a process for converting it to substituted azine compounds with herbicidal activity.

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 invention relates to the technical field of chemical synthesis of medicines, and particularly discloses a production and preparation method of an erlotinib intermediate. The method comprises the following steps: taking 3, 4-dihydroxy benzaldehyde as an initial raw material, sequentially carrying out etherification, oxidation and nitration reactions to prepare 2-nitro-4, 5-bis (2-methoxyethoxy) benzoic acid, finally dissolving the 2-nitro-4, 5-bis (2-methoxyethoxy) benzoic acid, formamide, formic acid and triethylamine in gamma-valerolactone to form two material flows, and carrying out heat treatment to obtain the 2-nitro-4, 5-bis (2-methoxyethoxy) benzoic acid. And carrying out continuous cyclization reaction in a fixed bed reactor filled with a specific composite catalyst, and carrying out post-treatment to obtain the target product 6, 7-bis (2-methoxyethoxy)-4-quinazolinone. According to the method, the raw materials are easy to obtain, the reaction efficiency and the product purity are remarkably improved by optimizing the synthesis route and the reaction conditions, and a novel efficient, environment-friendly and stable method is provided for large-scale production of the erlotinib key intermediate.

The invention discloses a nitrification method of trifluoromethoxybenzene based on a supercritical / subcritical technology. The disclosed scheme is as follows: trifluoromethoxybenzene and a nitrating agent are subjected to a nitration reaction under a supercritical fluid or subcritical fluid condition to prepare trifluoromethoxynitrobenzene. According to the method disclosed by the invention, the nitrification process is enhanced by utilizing the supercritical / subcritical fluid, so that the mass transfer and heat transfer efficiency is high, the raw material trifluoromethoxybenzene is nearly completely converted, the selectivity of the product trifluoromethoxynitrobenzene is high, meanwhile, the acid consumption in the nitrification process is greatly reduced, and the technological process is greener and more efficient.

Processes and facilities for producing several types of recycled content organic chemical compounds from waste plastic. Processing schemes are described herein for converting waste plastic (or hydrocarbon having recycled content derived from waste plastic) into useful intermediate chemicals and final products. In some aspects, recycled content aromatics (r-aromatics) can be processed to provide recycled content benzene (r-benzene) and / or recycled content toluene (r-toluene), which can be further processed to form a variety of intermediate and final organic chemical compounds including, but not limited to, recycled content nylons, recycled content polystyrene. recycled content benzoic acid, and recycled content phenol.