97 results about "P-chloroaniline" patented technology

The invention relates to water-soluble, chlorhexidine-containing compositions having a long shelf life. The compositions are in the form of powder, granules or tablets and consist substantially of (i) a salt of chlorhexidine with 2 moles of a sugar acid and a microbicidally active quaternary ammonium bromide, or of (ii) chlorhexidine, a sugar acid or sugar lactone, with at least 2 moles of sugar acid or sugar lactone being present per mole of chlorhexidine, and a microbicidally active quaternary ammonium bromide. Peferred compositions consist substantially of chlorhexidine digluconate and N-cetyl-N,N,N-trimethylammonium bromide (cetrimide) in a weight ratio of 1:1 to 1:10. The solid compositions are stable, with little or no p-chloroaniline splitting off during storage.

The invention relates to a treatment method for acyl-chlorination reaction tail gas. The reaction tail gas successively enters a three-step series hydrogen chloride falling-film absorption tower and a two-step series ammonium hydroxide absorption tower; p-chloroaniline and recovered hydrochloric acid are taken as raw materials and subjected to diazotization reaction for generating a diazo salt; and an aqueous solution of ammonium sulfite is taken as a reducing agent, after the diazo salt is dropwise added at room temperature, the recovered hydrochloric acid is dropwise added for acidification hydrolysis and further for preparing p-chlorophenylhydrazine hydrochloride. By employing the method to treat the acyl-chlorination reaction tail gas, tedious technologies for discharging and drying solid materials and selecting low-temperature equipment for liquefying sulfur dioxide are avoided, and the production operation is safe and convenient; and the produced tail gas absorption solution can be used as a raw material for preparing organic chemical products, is environment-friendly and is capable of creating economic benefit.

The invention discloses a preparation method of P-chlorophenylhydrazine hydrochloride. The method comprises the following steps: diazotizing chloroaniline taken as a raw material so as to prepare a corresponding diazonium salt; mixing anhydrous sodium sulfite with sodium hydrogen sulfite in a stirring manner, maintaining a pH (Power Of Hydrogen) value within 6 to 7, controlling a temperature below 40 DEG C, slowly adding the diazonium salt below a liquid surface and reacting at the temperature of 60 DEG C to 90 DEG C according to the molar ratio of the p-chloroaniline to the sodium hydrogen sulfite being 1:(1-1):3; maintaining the unchanged pH value in the step 2, slowly adding hydrochloric acid so as to maintain the pH value within 1 to 3, reacting for 1 to 3 hours at the reaction temperature of 40 DEG C to 90 DEG C, cooling to a room temperature, filtering and drying so as to obtain a reddish P-chlorophenylhydrazine hydrochloride solid. The pH value of the reaction system is maintained within 6 to 7 by taking a mixture of the sodium sulfite and the sodium hydrogen sulfite as a reducing agent, so that the phenomenon that the pH value is always regulated by NAOH (sodium hydroxide) or HCL (hydrogen chloride) in a reaction process is avoided; and the repeated heating during the reaction process is not required, so that the temperature is convenient to control; and the adding amount of water is reduced, so that the discharge of wastewater is greatly reduced, namely, the wastewater treatment at a later period is avoided. As a result, the cost is lowered.

The invention provides a synthesis method of parachlorophenylhydrazine hydrochloride. The synthesis method comprises the following steps: 1. diazotization of parachloroaniline; 2. reduction; 3. acidification; and 4. after-treatment. The synthesis method has the advantages of environment-friendly raw materials, simple synthesis technique, environment friendliness, low cost, high product yield, energy saving and consumption reduction, effectively lowers the production cost, and can enhance the economic benefit of the enterprise.

The invention belongs to the technical field of organic synthesis and provides a method for performing catalytic hydrogenation on p-chloronitrobenzene with a modified Raney nickel catalyst and preparing p-chloroaniline. The method comprises the following steps: adding p-chloronitrobenzene, the modified Raney nickel catalyst with an additional metal material and a solvent in a high-pressure reaction kettle, wherein the weight ratio of p-chloronitrobenzene to the solvent is 1:2-1:5 and the weight ratio of p-chloronitrobenzene to the catalyst is 1:(0.02-0.06); performing nitrogen replacement, then performing hydrogen replacement, wherein the pressure of hydrogen is 1.0-3.5MPa and the reaction temperature is 60-100 DEG C; and stirring to react for 1-4 hours to obtain the product p-chloroaniline. The method has simple technology, low demand on equipment and low environmental pollution and is easy to realize industrialization; and the reaction conversion rate is 99.9%, the selectivity is not less than 98% and the yield is not less than 95%.

This invention relates to a method for preparing 3, 4, 4'-trichloro-Triclosan benzene and two urea as a antiseptic including two-step reaction method, the first one is to take chloraniline as the raw material and toluene as the solvent to be reacted with solid phosgene to remove un-reacted solid phosgene and generated HCl gas to be decolored and filter solid impurities to get chlorophenyl phenyl isocyanate-toluene mother liquid, the second step is to synthesize said mother liquid with the 3, 4-dichloroaniline directly then to be filtered, cleaned and dried to get 3, 4, 4'-trichloro-triclosan benzene and two urea and the solvent is distilled and washed by acid, alkali and water to be reused.

The invention provides a method for synthesizing N-(4-chlorphenyl)-1,2-phenylenediamine as a key clofazimine intermediate. The method specifically comprises the following steps: 1) by taking o-fluoronitrobenzene and p-chloroaniline as raw materials and utilizing organic base as a catalyst for condensation reaction, reacting in an organic solvent and performing conventional treatment after ending the reaction, thereby acquiring a condensation intermediate N-(4-chlorphenyl)-2-nitryl-1-aniline; 2) by utilizing metallic nickel as the catalyst, performing catalytic hydrogenation reaction on the acquired condensation intermediate in the organic solvent and performing conventional treatment after reducing, thereby acquiring a rough product of N-(4-chlorphenyl)-1,2-phenylenediamine; and 3) re-crystallizing the acquired rough product with the organic solvent, thereby acquiring the end product.

The invention discloses a preparation method of an efavirenz intermediate, relating to synthesis of an anti-virus medicine, namely an efavirenz key intermediate by adopting a green solvent, namely 2-methyltetrahydrofuran as a Grignard reaction solvent, and belonging to the technical field of organic synthesis. The preparation method comprises the following steps of: taking the 2-methyltetrahydrofuran as a solvent, enabling metal magnesium to react with ethyl bromide to obtain ethyl magnesium bromide, then dripping cyclopropylacetylene to generate cyclopropyne ethyl magnesium bromide, and finally performing addition reaction with 2-trifluoroacetyl p-chloroaniline to obtain 2-(2-amino-5-chlorophenyl)-4-cyclopropyl-1, 1, 1-trifluoro-3-butyn-2-ol. According to the method, the 2-(2-amino-5-chlorophenyl)-4-cyclopropyl-1, 1, 1-trifluoro-3-butyn-2-ol can be prepared with high selectivity and high yield, the product purity is more than 99.8%, and the yield can achieve 95.2-97.1%. Compared with traditional technologies, the preparation method disclosed by the invention has the following advantages: as the green solvent, namely the 2-methyltetrahydrofuran is adopted in Grignard reaction, the yield is high, the selectivity is good, the product is easy to separate, the reaction conditions are easy to control, the using quantity of the solvent is small, and the solvent is easy to recover, so that the preparation method is in line with a green chemical idea and is suitable for industrial production.

The invention provides a method for reduction preparation of p-chloroaniline by photocatalysis. The process comprises the following steps: solving p-chloronitrobenzene with organic solvent in photocatalysis reactor allowing over 300nm ultraviolet light to pass with the mass ratio of p-chloronitrobenzene to solvent between 1í†40 and 1í†225, adding hole scavenger and photocatalyst with the volume ratio of hole scavenger to organic solvent between 1í†3 and 1í†18 with the concentration of photocatalyst in organic solvent between 0.5g/L and 10g/L, adding nitrogen for removing oxygen, and irradiating for 3 hours to 6 hours by ultraviolet light at normal pressure. The reduction reaction can be carried out at normal temperature without high temperature energy consumption device, initiation light can be ultraviolet light or sunlight, and nano photocatalyst can be titanium dioxide or zinc oxide, etc. The invention has higher reduction conversion and yield.

The invention relates to a p-chloroaniline isocyanate preparation method comprising the following steps: (1) p-chloroaniline hydrochloride is synthesized, wherein p-chloroaniline is adopted as a raw material and is subjected to a reaction with hydrochloric acid in an organic solvent, such that p-chloroaniline hydrochloride is synthesized; (2) p-chloroaniline isocyanate is synthesized, wherein p-chloroaniline hydrochloride and triphosgene are adopted as raw material, and p-chloroaniline isocyanate is synthesized in an organic solvent. The method provided by the invention has the advantages of advanced process route, reasonable process conditions, and high reaction yield. The materials used in production are not highly excessive; solvent dose in each step is low; and the solvent can be directly used without treatment. An intermediate is not needed to be dried, and can be directly used in the next step of reaction. Three-waste amount is low, and the waste is easy to treat. Therefore, the method has good implementation value and social benefit.

The invention discloses a powder catalyst, composed of GdSnWSbO9 and having a particle size of 0.15-0.30 mu m. The powder catalyst is capable of optically catalytically degrading organic pollutants inwater, such as p-chloroaniline, methyl orange and decabromodiphenyl ether. Also disclosed is a preparation method of the powder catalyst, comprising high-temperature solid sintering process, direct deposition process and chemical vapor condensation deposition process. The invention also discloses a preparation method of a composite nano catalytic material; GdSnWSbO9-Na-montmorillonite composite nano catalytic material prepared by the using the preparation method is applicable to removing the organic pollutants in water, such as p-chloroaniline, methyl orange and decabromodiphenyl ether, by photocatalysis.

The invention relates to the technical field of compound synthesis, in particular to a preparation method for high-purity pyraclostrobin. The pyraclostrobin is synthesized from p-chloroaniline and o-nitrosotoluene as initial raw materials through the steps of diazotizing, cyclizing, oxidizing, bromizing, condensating, reducing, acylating, methylating and the like. According to the preparation method, the problem that the purity of the pyraclostrobin in the prior art is low is solved; and the preparation method for the pyraclostrobin has the advantages of high yield, high purity and high material utilization rate.

The invention provides a p-chloroaniline hydrochloride preparation method, which comprises: in the presence of an organic solvent azeotropic with water, using p-chloronitrobenzene as a starting raw material, adding anti-dehalogenation agent and an acid binding agent, sealing, introducing hydrogen gas, carrying out a hydrogenation reaction under the catalysis of a platinum-carbon catalyst at a hightemperature under a high pressure, cooling, filtering to remove the catalyst, collecting the filtrate, adding concentrated hydrochloric acid to the filtrate, carrying out thermal insulation for 0.5-2h at a temperature of 80-95 DEG C, continuously heating to achieve a boiling state, refluxing by a water separator until no water is separated, filtering, and drying to obtain p-chloroaniline hydrochloride. According to the present invention, the preparation method has characteristics of mild and controllable reaction conditions, simple operation and low cost, performs the two steps through the one-pot method, and provides the advanced preparation method for industrial production.

The invention discloses a preparation method of tolvaptan key intermediate 7-chloro-5-oxo-1,2,3,4-tetrahydro-benzazepine. The preparation method comprises the steps of condensing parachloroaniline, which is taken as a starting raw material, with 4-chlorobutyric acid methyl ester, carrying out hydrolysis de-esterification and acylating chlorination, and carrying out ring closure under an acidic condition, so as to obtain a target product, wherein the total yield of the target product can reach above 80%, and the HPLC (High Performance Liquid Chromatography) purity reaches above 99.5%.

The invention relates to a method for producing o-nitro-p-chloroaniline by using chloridized aromatic hydrocarbon waste as a raw material. The method comprises the following three parts of: processing the chloridized aromatic hydrocarbon waste by utilizing a physical synthesis technology; separating high-content p-dichlorobenzene from the chloridized aromatic hydrocarbon waste by using a separated integration technology; and obtaining the o-nitro-p-chloroaniline as a target product by utilizing nitrification and ammonification technologies. The method provided by the invention has the advantages of effectively utilizing the waste and reducing the environmental pollution. In addition, by adopting the process provided by the invention, the problems described in the specification are effectively solved, and the process is simple and convenient for control and large-scale production.

A synthetic method of an Oxazolam drug intermediate 2-amino-5-chlorobenzophenone comprises the following steps: adding 3.51-3.55mol of benzamide into a reaction container provided with a stirrer, a thermometer and a reflux condenser, rising the temperature of a solution to 120-123 DEG C, dropwise adding 1.41mol of p-chloroaniline, after adding, slowly rising the temperature to 190-195 DEG C, adding 5.5-5.9 mol of stannous chloride, rising the temperature of a solution to 240-250 DEG C, reacting for 3-4h at the temperature until no gas is generated, reducing the temperature of a solution to 90-95 DEG C, adding 500ml of a potassium chloride solution, rising the temperature of a solution to 130 DEG C, performing backflow, pouring out a water layer after 3-4h, cooling a solution, then separating out a dark suspended matter, adding the suspended matter into 2.5L of a phosphoric acid solution, performing backflow for 20-23h, cooling, then pouring a solution into 1200ml of a sodium nitrate solution, reducing the temperature of a solution to 5-8 DEG C, adding cyclohexane for extraction, adding 300ml of a sodium sulfite solution in a cyclohexane layer, performing reduced pressure distillation, adding acetonitrile and extracting for 5-7 times, separating out a solid, filtering, and dehydrating by a dehydrating agent, thus obtaining the yellow crystal 2-amino-5-chlorobenzophenone.

The present invention provides a synthesis method of asulfentrazone intermediate. The methodcomprises: S1) carrying out a nitration reaction on chlorobenzene in a nitration reagent to obtain a mixture of o-chloronitrobenzene and p-chloronitrobenzene, wherein the product does not need to be separated; s2) performing catalytic hydrogenation reaction on the mixture of o-chloronitrobenzene and p-chloronitrobenzene to obtain a mixture of o-chloroaniline and p-chloroaniline, wherein the product does not need to be separated; s3) making the mixture of o-chloroaniline and p-chloroaniline subjected to a diazotization reaction to obtain a mixture of o-chlorophenylhydrazine and p-chlorophenylhydrazine, wherein the product does not need to be separated; s4) performing condensation reaction on the mixture of the o-chlorophenylhydrazine and the p-chlorophenylhydrazine and aldehyde to obtain triazole ring mixtures as shown in a formula I-a and a formula I-b; and S5) carrying out chlorination reaction on the triazole ring mixtures to obtain the sulfentrazone intermediate shown in the formula I. According to the method, 2, 4-dichloroaniline is not used as a raw material, so that the production cost of sulfentrazone is reduced, and the limitation of raw material supply is avoided.

The invention relates to an application of an antioxidant in distillation reaction of 2, 5-dichloroaniline. The process comprises the following steps: simultaneously adding a generated crude product, namely the 2, 5-dichloroaniline and the antioxidant into a distillation kettle after the reaction of 2, 5-dichloronitrobenzene and hydrogen is completed and reacting during the distillation process to get a final product, namely p-chloroaniline. The antioxidant comprises the component of sodium sulfide, and the concentration is 0.1%. The temperature of the distillation reaction is 130 DEG C, and the pH value during the reaction process is 10-11. The application disclosed by the invention has the advantages that compared with other antioxidants, the application of the antioxidant has better stability, good heat resistance and good oxidation resistance, and can keep the color and the appearance of the material for a long time. The application disclosed by the invention further has the advantages of simple process, low production cost, low toxicity and good oxidation resistance of the product, and is suitable for green industrial production.

The invention provides an application of a supported porous nano platinum-ruthenium alloy catalyst in preparation of o-(m-, p-) chloroaniline by hydrogenation of o-(m-, p-) chloronitrobenzene. The catalyst takes a metal oxide or a carbon material as a carrier and a porous nano platinum-ruthenium alloy as an active component, and the porous nano platinum-ruthenium alloy is formed by mutually connecting platinum-ruthenium alloy particles; in the porous nano platinum-ruthenium alloy, ruthenium is enriched on the outer layer of the porous nano platinum-ruthenium alloy. The preparation process of the catalyst comprises the following steps: (1) preparing the porous nano platinum-ruthenium alloy; (2) loading the porous nano platinum ruthenium alloy; and (3) post-treating the catalyst. The optimized catalyst is obtained by optimizing the preparation conditions of the porous nano platinum-ruthenium alloy, screening the carrier and optimizing the operation method of post-treatment. The catalyst prepared by the invention can catalyze the hydrogenation of ortho (m, p) chloronitrobenzene to prepare ortho (m, p) chloroaniline with high conversion rate and high selectivity under the reaction conditions of no use of a dechlorination inhibitor and wide range.

The invention discloses a salicylic acid modified styrene polymer and a method for adsorbing and recovering aniline components in industrial waste water by using the salicylic acid modified styrene polymer. According to the method, the synthesized salicylic acid modified styrene polymer serves as an adsorbing material to adsorb the aniline components such as aniline, p-aminotoluene, p-chloroaniline and para aminobenzoic acid in the waste water, and the maximal adsorption capacity can reach to 132, 155, 229 and 113 mg/g respectively. Experimental results show that the adsorption capacity is obviously higher than the maximal adsorption capacity, on the aniline compounds, of the adsorbing materials such as active carbon, coal ash and modified zeolite. The method provided by the invention hasthe advantages of simple material preparation process, reusability, mild adsorption condition, energy conservation, environmental friendliness, low cost and the like.

The invention relates to a process for reducing the residual amount of p-chloroaniline in chlorhexidine. Also, the invention relates to a process for preparing chlorhexidine, or a pharmaceutically acceptable salt thereof, which is free of potential genotoxicity. In addition, the invention refers to the said chlorhexidine, or a pharmaceutically acceptable salt thereof, which is free of potential genotoxicity. Further, the invention relates to an analytical HPLC method for the determination of potentially genotoxic impurities in samples of chlorhexidine, or of a pharmaceutically acceptable salt thereof. The invention also relates to stabilized chlorhexidine digluconate salt free of potential genotoxicity in aqueous solution, and to a method for stabilizing chlorhexidine digluconate salt free of potential genotoxicity in aqueous solution.