844 results about "Reaction step" patented technology

The invention discloses a synthetic method of a water soluble ultraviolet light absorber BP-9. The method mainly comprises the following process steps: (1) carrying out methylation on the main raw materials of 2, 2', 4, 4'-tetrahydroxyl benzophenone, a transition metal salt catalyst and a mixed solvent which is prepared from dichloroethane and anhydrous ethanol in equal parts by weight to obtain 2, 2'-dihydroxyl-4, 4'-dimethoxyl benzophenone; (2) carrying out sulfonation reaction on the main raw materials of methylate, sulfamic acid and C1-C3 halohydrocarbon to obtain 2, 2'-dihydroxyl-4, 4'-dimethoxyl benzophenone-5, 5'-disulfonic acid; and (3) carrying out neutral reaction on the main raw materials of sulfonated product, inorganic base and ethanol water to finally obtain the BP-9 product. The synthetic method disclosed by the invention is few in reaction step, low in cost, high in product purity and stable in quality, and raw materials are easily available.

The invention provides a method for preparing squaric acid and a method for preparing a lithium supplement agent of lithium squarate. The method for preparing squaric acid comprises the steps of preparing an intermediate I, preparing an intermediate II and preparing squaric acid. The method for preparing the squaric acid is a novel squaric acid synthesis route, and the squaric acid is obtained through cycloaddition / substitution reaction of perchloroprene serving as an initial raw material and morpholine, hydrolysis / rearrangement reaction in a buffer system and acid hydrolysis reaction in sequence. The method for preparing squaric acid has the advantages of simple reaction steps, mild reaction conditions, high yield, low cost and the like. The invention also provides a method for preparing the lithium squarate lithium supplement agent, and the prepared squaric acid and lithium-containing alkali are blended in a solvent for reaction to generate the lithium squarate. The method for preparing the lithium squarate lithium supplement has the advantages of simple reaction steps, mild reaction conditions, high yield, low cost and the like.

The invention belongs to the field of chemistry and chemical engineering, and discloses a method for preparing high-purity 1, 4-dioxane-2-ketone at low cost. A large amount of high-purity 1, 4-dioxane-2-ketone can be prepared at one time by taking a large amount of glycollic acid or glycollic acid derivatives and ethylene oxide as raw materials and adopting a one-step synthesis process route and a purification mode suitable for industrial production. According to the method, cheap bulk commodities are adopted as raw materials, and high-value conversion of low-value chemicals is achieved; according to the method disclosed by the invention, the 1, 4-dioxane-2-ketone is rapidly synthesized in one step under mild conditions without a catalyst or with a trace amount of a catalyst, so that the synthesis yield of a target product is improved, the reaction steps are greatly shortened, the energy consumption is greatly reduced, and the production cost is obviously reduced.

The synthesis method comprises the following steps: S1, adding furandicarboxylic acid into a reaction container, adding a certain amount of methanol, adding a double-acid-site strong acid solid catalyst, starting stirring, controlling the reaction temperature to carry out esterification reaction, and after the reaction is finished, filtering, washing and drying to obtain furandihydrazide; separating out the double-acid-site strong acid solid catalyst to obtain clear liquid, namely dimethyl furandicarboxylate; s2, transferring dimethyl furandicarboxylate serving as a raw material into another reaction container, adding a certain amount of sodium formate serving as a catalyst, then adding a proper amount of hydrazine hydrate, controlling the reaction temperature, keeping a reflux state, reacting for a period of time, cooling to room temperature after the reaction is finished, and performing centrifugal separation to obtain white solid furandihydrazide. The synthesis method has the advantages of simple reaction steps, no need of toxic and harmful catalysts, mild reaction conditions, high conversion rate and high yield, and can realize efficient, green and low-cost production of furandihydrazide.

The invention provides a preparation method and application of an asymmetric dicyclopentadienyl dialkoxy zirconium compound, and the preparation method comprises the following steps: (1) mixing a solvent with ZrCl4 and sodium cyclopentadienyl CpNa, and carrying out a reaction to obtain CpZrCl3; (2) the CpZrCl3 obtained in the step (1) and R1 substituted sodium cyclopentadienyl R1CpNa are subjected to a mixed reaction, and (R1Cp) CpZrCl2 is obtained; and (3) mixing the (R1Cp) CpZrCl2 obtained in the step (2) with alkoxy sodium salt R2Na, and carrying out a reaction so as to obtain the asymmetric dicyclopentadiene dialkoxy zirconium compound. According to the method, the substitution reaction of three sodium salts is used for replacing the ligand replacement reaction in the prior art, so that the reaction steps are shortened, the use of unnecessary raw materials is avoided, the production cost is reduced, and the obtained target product is high in yield and high in purity.

The invention provides a continuous process for preparing aromatic hydrocarbon by supercritical carbon dioxide hydrogenation, which comprises the following steps: 1) adding a reaction liquid containing a solvent and a catalyst into a reaction kettle, spraying supercritical carbon dioxide and hydrogen into a reactor by adopting a Venturi ejector, and contacting with the catalyst in the reaction kettle to react; (2) after the reaction in the step (1), the gas in the reactor is sequentially subjected to primary condensation and secondary condensation to respectively condense the solvent and the water, the solvent of the primary condensation returns to the reaction kettle, the water of the secondary condensation is discharged, and the gas after the secondary condensation sequentially passes through an absorption tower and a desorption tower to capture non-aromatic hydrocarbon, the residual gas is used as recycle gas and returns to the Venturi ejector to enter the reaction kettle; and (3) pressurizing the reaction liquid discharged from the reaction kettle after the reaction in the step (1) through a circulating pump, feeding the reaction liquid into a heat exchanger to remove reaction heat, dividing the reaction liquid subjected to heat exchange into two streams through a cross-flow filter, feeding one stream of penetrating fluid into a rectification device, and feeding the other stream of concentrated liquid back to the reaction kettle for continuous reaction.

The invention discloses a method for preparing poly (butylene adipate-co-terephthalate) by a one-step method. The method comprises the steps of terephthalic acid esterification, adipic acid esterification, secondary esterification of terephthalic acid esterification liquid and adipic acid esterification liquid, and condensation polymerization, wherein terephthalic acid esterification and adipic acid esterification are synchronously carried out; in the terephthalic acid esterification process, a catalyst and a heat stabilizer are mixed and heated to obtain a mixed catalyst, and after terephthalic acid esterification reaction generates water, the mixed catalyst is added into a reaction system in a manner of feeding under the liquid level, so that on one hand, hydrolysis of the catalyst is reduced, and the catalytic efficiency of the catalyst is improved; on the other hand, the heat exchange efficiency is reduced and the energy consumption is increased due to the fact that a catalyst hydrolysis product covers a heat exchange pipeline; under the condition of not supplementing a catalyst, the synthesized product with qualified indexes such as PBAT melt index, color value, terminal carboxyl group and the like can be realized through subsequent secondary esterification and polycondensation.

The invention discloses a spherical Prussian blue material as well as a preparation method and application thereof. The preparation method comprises the following steps: enabling a mixed reaction system containing soluble transition metal hexacyanoid salt, soluble transition metal salt, a complexing agent, soluble sodium salt, a surfactant and a carbon sphere precursor to react, and then selectively performing or not performing aging treatment to prepare the spherical Prussian blue material. According to the preparation method provided by the invention, the spherical Prussian blue material is obtained by regulating and controlling the reaction raw materials and the reaction steps, so that the rate capability and the cycle stability of the Prussian blue material are improved, and the problem that the compaction density and the compaction density are reduced due to the fact that the rate capability of a Prussian blue cube is improved due to carbon coating is solved.

The invention relates to the technical field of sodium silicate production, and particularly discloses a method for preparing sodium silicate by dissolving fluorine-containing silicon dioxide with alkali lye, which comprises the following steps: step 1, adding fluorine-containing silicon dioxide, sodium carbonate and water into a reaction kettle with a stirrer and a heating device to obtain a mixed material; 2, fully and uniformly stirring the mixed material obtained in the step 1, heating the mixed material by using a reaction kettle, and controlling the reaction temperature and the reaction time for reaction; and 3, filtering and separating the reaction product obtained in the step 2 to obtain a sodium fluoride filter cake and a sodium silicate solution. Sodium carbonate and sodium bicarbonate are used for dissolving silicon dioxide in a liquid phase reaction to prepare sodium silicate, the process is green and environment-friendly, sodium carbonate in chemical production can be effectively utilized, energy is saved, consumption is reduced, and the environment is protected. The technical problems that in the prior art, the temperature is high in the reaction process, a large amount of heat needs to be consumed, and energy consumption is high are solved.

The invention discloses a preparation method of protecting group cefdil side chain acid. The preparation method comprises the following reaction steps: step 1, performing oximation reaction on a compound IV to obtain a compound V; 2, cyclizing the compound V and thiourea to obtain a compound VI; 3, condensing the compound VI and tert-butyl alpha-bromoisobutyrate to obtain a compound VII; 4, the compound VII passes through a protective group to obtain a compound VIII; and 5, hydrolyzing the compound VIII to obtain the product protecting group cefdil side chain acid. The raw materials used in the method are simple and easy to obtain, expensive reagents and customized raw and auxiliary materials are not used, the process operation is simple, a major dangerous process is not involved, and the method has industrial advantages.

The method is for producing para-xylene using, as a main raw material, a mixed gas of carbon dioxide or carbon monoxide or both thereof and hydrogen. The method including: a reaction step of bringing a raw material mixed gas including the mixed gas into contact with a reaction catalyst under high temperature and high pressure to cause a reaction, to thereby obtain a product gas mixture containing para-xylene; a separation step of cooling the product gas mixture obtained in the reaction step to condense a high boiling point component, to thereby separate the product gas mixture into a water phase containing a water-soluble component, an oil phase containing a xylene mixture, and a gas phase containing an unreacted gas; and a circulation step of mixing at least part of the gas phase having been separated in the separation step into the raw material mixed gas.

To provide: a methane production device and a methane production method which, in production of methane gas by bio-methanation, enable supply of the methane gas at a proper concentration required on a use place where the methane gas is used; and a power generation system utilizing the methane production device.SOLUTION: A methane production method according to the present invention, which is for performing methane production based on bio-methanation, includes: a reaction step of performing a methanation reaction with hydrogen gas and biogas being supplied; and a control step of controlling the efficiency of the methanation reaction to obtain methane gas having any methane concentration. According to the methane production method, the methane gas can be supplied at a proper concentration adapted to a use place of the methane gas. A power generation system according to the present invention utilizes the methane gas obtained from a methane production device according to the present invention. The power generation system enables the methane production device to have a high efficiency without replacing an existing gas power generator.SELECTED DRAWING: Figure 1

Disclosed is a process for the synthesis of mono- and bis-nitrosylated propanediols, as well as compositions and pharmaceutical formulations that includes the compounds. The process proceeds by reacting a corresponding propanediol that is not nitrosylated with a source of nitrite, optionally in the presence of a suitable acid. When the source of nitrite is an organic nitrite, reacting step is performed in a suitable organic solvent, and when the source of nitrite is an inorganic nitrite, the reacting step is performed in a bi-phasic solvent mixture comprising an aqueous phase and a non-aqueous phase. Also disclosed are methods of treating a condition wherein administration of nitric oxide (NO) has a beneficial effect by administering said compounds, compositions or formulations.

The application provides a preparation method of finerenone and intermediates thereof. The application discloses a preparation method of a finerenone intermediate 5, which comprises the following steps: step 1: in an organic solvent, a resolution reaction is carried out between a finerenone intermediate 2 and D-tartaric acid diphenyl ester to obtain a resolution salt, then an acid-base reaction is carried out between the resolution salt and a base to obtain the finerenone intermediate 3; step 2: in an organic solvent, a nucleophilic substitution reaction is carried out between the finerenone intermediate 3 and triethyl orthoformate in the presence of an acid to obtain a finerenone intermediate 4; step 3: in a solvent, a hydrolysis reaction is carried out between the finerenone intermediate 4 to obtain the finerenone intermediate 5. The preparation method has the advantages of short reaction steps, high total reaction yield, simple and safe operation, simple post-treatment steps, high product purity, low production cost and suitability for industrial production.

The invention discloses a preparation method of fluorine-containing soluble polyimide, and relates to the technical field of high polymer materials, and the preparation method comprises the following steps: S1, preparing a fluorine-containing diamine monomer; s2, carrying out segmented temperature control polymerization reaction; step S3, carrying out gradient heating imidization reaction; and S4, precipitating and purifying. The fluorine-containing soluble polyimide prepared by the preparation method of the fluorine-containing soluble polyimide is simple in process, mild in reaction condition and excellent in product performance.

The application relates to a preparation method of PdAg nanosponge and application of the PdAg nanosponge. A certain amount of ethylene glycol is configured into an ethylene glycol aqueous solution, a certain volume of the ethylene glycol aqueous solution is added into a reaction container, then a certain amount of a Pd precursor is quickly added into the ethylene glycol aqueous solution, a certain amount of an Ag precursor is further added, the reaction system is uniformly mixed through ultrasonic, and then the reaction system is statically reacted at 20-60 DEG C for 0.5-3.0 h. After the reaction is completed, the reaction product is centrifuged, the obtained precipitate after centrifugation is washed through ultrapure water, and the PdAg nanosponge is obtained after drying. The application does not need to use a surfactant and a template agent, does not need to additionally add a reducing agent, does not need high temperature, high pressure, stirring and other reaction conditions, and can be statically reacted at 20-60 DEG C, so that the reaction condition is mild and the reaction step is simple. The prepared PdAg nanosponge has a 3D sponge-like structure and is a self-supporting catalyst, the purity is high, and the PdAg nanosponge has excellent catalytic activity and selectivity for selective hydrogenation reaction of furfural.

The present disclosure relates to a method for producing a secondary amine or tertiary amine or mixture thereof in a single reaction step and the use of such amines in various applications including, but not limited to, polyurethane, oil & gas, metalworking, paints and other coatings applications.

The invention relates to the technical field of polyphenylene sulfide, in particular to low-molecular-weight polyphenylene sulfide low in chlorine and easy to purify and a preparation method thereof.The method comprises the steps that 1, sodium hydroxide, sodium acetate and sodium hydrosulfide with the required amount are sequentially put into a reaction kettle, then N-methyl pyrrolidone is added, and heating dehydration is conducted under nitrogen protection to obtain a mixed solution; step 2, adding preheated paradichlorobenzene into the mixed solution, adding a part of phase control agent at the required polymerization temperature and under the protection of nitrogen, and carrying out prepolymerization stage reaction; and step 3, after the prepolymerization stage is completed, carrying out segmented temperature control on the reaction system, adding the residual phase control agent, carrying out polymerization stage reaction, and after the reaction is completed, obtaining the low-molecular-weight polyphenylene sulfide which is low in chlorine and easy to purify. The low molecular weight polyphenylene sulfide with low chlorine radical residue and low ash content is prepared, the phase control agent is easy to prepare and low in price, and the preparation method is easy and convenient to operate and convenient to popularize and apply.

The present invention relates to a method for preparing a high-purity peramivir intermediate. The method comprises the following steps: Step 1: adding compound II to a reaction kettle, and dropwise adding a sodium borohydride methanol solution; after the dropwise addition is completed, the reaction is stirred at a controlled temperature; purified water and a sodium nitrite solution are added, and the reaction is stirred to prepare compound (III); Step 2: adding acetic anhydride dropwise to compound (III), and the reaction is stirred at a controlled temperature; Step 3: adding a sodium carbonate aqueous solution, stirring, separating the liquids, collecting the organic phase, concentrating under reduced pressure, adding a solvent, stirring and crystallizing, and centrifuging until no obvious liquid flows out; vacuum drying the filter cake to obtain an off-white crude peramivir acetylate (IV); Step 4: refining to obtain an off-white solid peramivir acetylate (IV). #imgabs0#

The invention belongs to the technical field of organic synthesis, and relates to a preparation method of bis (trimethylolpropane), which comprises the following steps: preparing 2, 2-bis (hydroxymethyl) butyraldehyde from trimethylolpropane under the action of an oxidant; then, trimethylolpropane and 2, 2-bis (hydroxymethyl) butyraldehyde are subjected to reductive etherification under the action of a reductive etherifying agent and a catalyst, and the target product bis (trihydroxymethyl) propane is obtained. The preparation method of bis (trihydroxymethyl) propane has the advantages of few reaction steps and mild conditions, can improve the reaction yield, and is beneficial to the realization of industrial application.

The invention relates to a process for obtaining isobutene from an isobutene containing C4-hydrocarbon mixture (1) in a plant comprising an etherification unit (3), a first distillation unit (5), an ether cleavage unit (10) and a second distillation unit (12), the process comprising: (a) contacting the C4-hydrocarbon mixture (1) with a primary alcohol (2) and reacting the mixture with the primary alcohol in the presence of an acidic catalyst to form the corresponding alkyl tert-butyl ether in the etherification unit (3); (b) distilling the reaction mixture (4) from the etherification unit (3) in the first distillation unit (5), a C4-hydrocarbon raffinate being withdrawn as the overhead product (6), and the alkyl tert-butyl ether being withdrawn as the bottom product (7); (c) vaporizing the bottom product from the first distillation unit (5) in an evaporator (8) obtaining a vapor stream (9); (d) reacting the vapor stream (9) of step (c) in the presence of an acidic catalyst obtaining isobutene and the primary alcohol as reaction products in the ether cleavage unit (10); (e) distilling the reaction mixture (11) from the ether cleavage unit (10) in the second distillation unit (12), isobutene being withdrawn as the overhead product (13), the primary alcohol and diisobutene being withdrawn as the bottom product (14) and being recycled to the etherification unit (3); wherein a purge stream (15) containing high boiling components with a normal boiling point higher than that of the alkyl tert-butyl ether is withdrawn from the evaporator (8) in step (c).

To provide: a production method for powder having reduced specific surface area which enables the powder having reduced specific surface area to be easily produced; and a powder production device.SOLUTION: A production method for powder having reduced specific surface area includes: a reaction step of supplying gas G containing carbon dioxide to a solution 3 containing a metal ion to react the metal ion and a carbonate ion to produce an intermediate 7; and a separation step of separating the intermediate 7 from the solution 3 to produce carbonate mineral powder 2 which is powdered. During the reaction step, a surfactant S for reducing specific surface area of the intermediate 7 is added to the solution 3.SELECTED DRAWING: Figure 1

The present application relates to a kind of phenol and methanol directly prepared (methyl) anisole mode, the method includes the following steps: under the action of composite catalyst, phenol and methanol are catalytically generated methyl anisole, the composite catalyst is Ho / β molecular sieve catalyst and Ti / UiO-66 with mass ratio Ho / β:Ti / UiO-66 0.3-0.6:1 Mixed composite catalyst.The process reaction step is simple, and synthesis is realized in one step, and the total selectivity of methyl anisole is as high as 76% or more, and can be continuously and stably operated for 3000h.

The application discloses a preparation method of a key intermediate of dapagliflozin, and belongs to the technical field of preparation of medical intermediates. The preparation method of the key intermediate of dapagliflozin comprises the following steps: 1, 1-ethoxy-4-methylbenzene is prepared by using p-cresol, sodium hydroxide and diethyl sulfate; 2, (4-ethoxybenzyl) phenyl sulfide is prepared by using 1-ethoxy-4-methylbenzene, thiophenol, a palladium catalyst, an alkali and an oxidant; 3, 1-benzyl-4-ethoxybenzene is prepared by using (4-ethoxybenzyl) phenyl sulfide under a hydrogen atmosphere; 4, 4-ethoxy-2'-chlorobenzhydrol is prepared by carrying out chlorination reaction on 1-benzyl-4-ethoxybenzene; and 5, 5-bromo-2-chloro-4'-ethoxybenzhydrol is prepared by carrying out bromination reaction on 4-ethoxy-2'-chlorobenzhydrol. The yield and purity of 5-bromo-2-chloro-4'-ethoxybenzhydrol prepared by the method are higher, the process is safer, and the production cost is reduced.

The invention discloses a method for synthesizing a sulfur-containing compound by using an amino sulfur trifluoride compound, which comprises the following two steps: S1, by taking the amino sulfur trifluoride compound and a compound A as reactants, stirring and reacting for 8-15 minutes or 10-15 hours at normal temperature in an organic solvent under an alkaline condition; the compound A is any one of an amide compound or a sulfanilamide compound, or water; and S2, adding a nucleophilic reagent into the solution after the reaction in the step S1, stirring at normal temperature to react for 8-15 minutes or 5-8 hours, and then purifying through a rapid chromatography to obtain a final product, namely, all-heteroatom substituted thioimine or all-heteroatom substituted sulfoxide, the nucleophilic reagent is an alcohol or an amine. According to the method disclosed by the invention, the amido sulfur trifluoride compound is used for synthesizing the asymmetric full heteroatom substituted thioimine and sulfoxide compound for the first time, the reaction steps are simple, the reaction conditions are mild, and expensive reagents are not needed.

The invention discloses tetraacetyl dicyclopropyl hexaazaisowurtzitane, a preparation method thereof and a synthesis method of HNIW, and belongs to the technical field of chemical synthesis. The tetraacetyl dicyclopropyl hexaazaisowurtzitane disclosed by the invention is a novel hexaazaisowurtzitane derivative, and the preparation method of the tetraacetyl dicyclopropyl hexaazaisowurtzitane has the advantages of short reaction steps, simplicity in operation, easily available raw materials and industrial application potential. The tetraacetyl dicyclopropyl hexaazaisowurtzitane disclosed by the invention can be used for synthesizing hexanitrohexaazaisowurtzitane (HNIW) in one step through nitration, so that the synthesis process is simplified, and the production cost is reduced; the specific gravity of the leaving group cyclopropyl in the cyclopropylamine raw material is small, the atom economy is good, the utilization rate of the raw material is high, waste discharge is reduced, and the method conforms to the environmental protection concept of green economy.

A preparation method of N '-((2S, 3S)-2-(benzyloxy) pent-3-yl) formylhydrazine oxalate enzyme belongs to the field of medical intermediates, and comprises the following steps: step 1, preparing a buffer solution of a compound enzyme preparation; step 2, adding (2S)-2-benzyloxy-3-pentanone into a solvent A, and then adding a buffer solution of the compound enzyme preparation for reaction; 3, filtering, and carrying out an activation reaction on the filtrate; 4, filtering, removing the solvent, adding the obtained solid into a solvent B, and then adding formylhydrazine for reaction; 5, filtering, removing the solvent, adding the obtained solid into a solvent C, and then adding oxalic acid for reaction; and 6, drying the solid obtained by filtering to obtain the N '-((2S, 3S)-2-(benzyloxy) pent-3-yl) formylhydrazine oxalate. According to the method, the yield of the N '-((2S, 3S)-2-(benzyloxy) pent-3-yl) formylhydrazine oxalate can be increased, and the production cost is effectively reduced.

1,2-propanediol is prepared by a process comprising the steps of: step a) reacting propene with hydrogen peroxide in the presence of a catalyst mixture comprising a phase transfer catalyst and a polytungstophosphate at 50-110°C in a liquid reaction mixture comprising an aqueous phase having a maximum apparent pH of 6 and an organic phase; step b) separating the reaction mixture into an aqueous phase (P a ) and an organic phase (P o ) comprising 1,2-propanediol; step c) recycling at least a portion of the separated organic phase (P o ) to step a); step d) recovering 1,2-propanediol from the aqueous phase (P a ); and step e) reacting a tungstate with hydrogen peroxide and phosphoric acid in the presence of a phase transfer catalyst in a liquid mixture comprising an aqueous phase and an organic phase at 5-40°C, followed by passing at least a portion of the resulting organic phase comprising polytungstophosphate and phase transfer catalyst to reaction step a).

The invention discloses a black phosphorus-methylene blue nano composition for improving blood brain permeability and a synthesis method thereof. The synthesis method comprises the following steps: step 1, mixing black phosphorus nanosheets with polyethylene glycol for reaction; step 2, carrying out centrifugal cleaning on the reaction liquid in the step 1, and collecting a lower-layer reactant; step 3, adding aminated superparamagnetic nanoparticles and methylene blue into the lower reactant obtained in the step 2 for reaction; and 4, carrying out centrifugal cleaning on the reaction liquid obtained in the step 3, and collecting a lower-layer reactant. The invention also discloses the black phosphorus-methylene blue nano composition synthesized by the synthesis method, the drug loading rate of methylene blue in the composition exceeds 60%, and the composition has good biological safety, is non-toxic to cells and mice, is very simple and convenient in preparation process, and has a wide application prospect in the aspect of improving the blood-brain barrier permeability.