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50 results about "Ethenone" patented technology

Ethenone is the formal name for ketene, an organic compound with formula C₂H₂O or H₂C=C=O. It is the simplest member of the ketene class. It is a tautomer of the even less stable ethynol.

Synthesis method of felinone intermediate

The invention discloses a synthesis method of a felinone intermediate, and relates to the technical field of medicine synthesis. The synthesis method comprises the following steps: firstly, taking a 500ml four-neck flask, adding 200ml of dichloromethane, adding 40g of 3-hydroxypropionitrile, finally adding 5g of a DMAP solid material, and stirring for 1 hour; continuously dropwise adding 50 g of ketene dimer, and after temperature-controlled dropwise adding is completed, carrying out heat preservation reaction for 2 hours to obtain a reaction solution; and taking the reaction liquid, washing with 200ml of saturated saline solution, preserving heat, taking the lower-layer material, washing with 200ml of purified water, preserving heat, taking the lower-layer material, finally washing with 200ml of saturated saline solution, taking the lower-layer material, distilling, and desolventizing to obtain the target product. The preparation method comprises the following steps: putting 40g of a target product and 200ml of DMF (Dimethyl Formamide) into a 500ml four-mouth flask, stirring, then adding 50g of 4-cyano-2-methoxybenzaldehyde into a constant-pressure dropping funnel and the like; the synthesis method is stable in reaction, low in raw material price, reasonable in synthesis route, basically free of by-products in the synthesis process, and high in target product purity.
Owner:QINGDAO RUIFENGYUAN CHEM CO LTD

Hydrolysis-resistant acetoacetamido-modified polyvinyl alcohol and a method for preparing the same

The application discloses a kind of hydrolysis-resistant acetylacetamide modified polyvinyl alcohol and preparation method thereof, and the preparation method comprises the following steps: double vinyl ketone and first and alcohol amine compound are reacted to generate N-(hydroxyalkyl) acetylacetamide intermediate;Then trichloro cyanogen and N-(hydroxyalkyl) acetylacetamide intermediate are reacted to generate 3,5-bis[acetylacetamide alkoxyl] monochloro s-triazine;Finally, 3,5-bis[acetylacetamide alkoxyl] monochloro s-triazine is reacted with PVA in polar solvent to generate AAM-PVA.The AAM-PVA prepared in the application can be used as a protective colloid for polyvinyl acetate emulsion polymerization, and the prepared emulsion adhesive has obvious improvement in water resistance, tensile strength and stability;The raw materials of the application are cheap and easy to obtain, the preparation process is simple, the reaction conditions are mild, and there is no waste water and waste gas emission.
Owner:NANJING TECH UNIV

Preparation method of ethyl 4-chloroacetoacetate

The invention discloses a preparation method of ethyl 4-chloroacetoacetate, and belongs to the technical field of compound synthesis. The method comprises the following steps: by taking diketene as a raw material, adding a polymethylsilsesquioxane polymerization inhibitor into a dichloromethane solvent, introducing chlorine at low temperature, carrying out chlorination reaction to generate 4-chloroacetoacetic acid, then esterifying the 4-chloroacetoacetic acid with absolute ethyl alcohol to obtain a crude product, and finally distilling and purifying to obtain the product. The preparation method is characterized in that a polymethylsilsesquioxane polymerization inhibitor is added before chlorination reaction, the polymerization inhibitor is prepared by grafting a functional monomer containing a 3, 5-di-tert-butyl-4-hydroxycinnamic acid structure onto surface-ethenylated polymethylsilsesquioxane microspheres, and the polymethylsilsesquioxane polymerization inhibitor has both steric hindrance and free radical capture capability. The method can effectively inhibit the self-polymerization and copolymerization tendency of diketene, intermediates and products in a reaction system, obviously reduces the generation of by-products such as dichloro and polychloro, enables the product to be high in yield and good in purity, and meets the quality requirements of high-end medical intermediates.
Owner:INNER MONGOLIA HUAZHOU PHARM CO LTD

Acetoacetate rectification method and rectification system

The invention discloses a rectification method and a rectification system for acetoacetic esters, and belongs to the technical field of chemical engineering. According to the method disclosed by the invention, a method of firstly removing high boilers and then removing low boilers is adopted, firstly, the high boilers in the crude ester are quickly removed at the initial stage of rectification, most high polymers such as tar are removed, side reactions caused by high polymer impurities in the subsequent rectification process are avoided, and then the low boilers are removed through rectification to obtain a finished product. According to the rectification mode, the residence time of the high-boiling residues is short, the treatment efficiency is higher, the yield and the purity of the acetoacetate crude ester prepared by taking the crude diketene as the raw material can be guaranteed or improved, the energy consumption is lower, the equipment is simpler, the occupied area is smaller, the investment is lower, and the method has the advantages that the materials are recycled, the energy consumption is saved and the production is safe; the method is suitable for industrial application.
Owner:NANTONG ACETIC ACID CHEM

A process for the preparation of 6-cyano-5-hydroxy-3-oxohexanoate

The present application relates to the technical field of pharmaceutical chemistry, and particularly to a preparation method of 6-cyano-5-hydroxy-3-oxohexanoate.The preparation method of 6-cyano-5-hydroxy-3-oxohexanoate comprises the following steps: carrying out a first reaction of cyanoacetaldehyde, divinyl ketone, alcohol and a catalyst in an organic solvent to obtain the 6-cyano-5-hydroxy-3-oxohexanoate.By adopting the reaction of cyanoacetaldehyde, divinyl ketone and alcohol, the 6-cyano-5-hydroxy-3-oxohexanoate is synthesized by one-step method, the process route is shortened, the steps are less, and the operation is simple;the use of toxic cyanide and alkali metal reagents is avoided, and the 6-cyano-5-hydroxy-3-oxohexanoate can be obtained at high yield and high purity.
Owner:ZHEJIANG CAIHE BIOTECHNOLOGY CO LTD

Filter media

A filter element is disclosed made from a gathered paper web that may be crimped, embossed, and / or corrugated. In accordance with the present disclosure, the paper web is treated with at least two different additives. The first additive comprises amphiphilic molecules, having hydrophilic and hydrophobic ends such as a ketene dimer that has one or more branching groups. The second additive, on the other hand, may comprise a polymer component such as a polyalkylene glycol. The filter element may also be treated with a polyamine or an amino acid or salt thereof. In one embodiment, the filter element may be incorporated into the filter of a smoking article. The two additives together may improve smoke taste, reduce some smoke phenols, and reduce some smoke carbonyls.
Owner:SWM LUXEMBOURG +1

A process for the preparation of 3-chloro-n-hydroxy-2-oxo-propionimidoyl chloride

PendingCN122102945APreparation from carboxylic acid halideOximes preparationOrganic synthesisWater chlorination
The present application relates to a kind of preparation methods of 3-chloro-N-hydroxy-2-oxo-propylimino chloride, belong to the technical field of organic synthesis.The synthetic route is as shown in the following:;Including the following steps: (1) with divinyl ketone as raw material, first with chlorine gas and 4-chloro-3-oxobutyryl chloride is obtained;Then hydrolysis obtains 4-chloro-3-oxobutyric acid;(2) by oximation and obtain 1-chloro-3-(hydroxy imino) acetone;(3) by chlorination and obtain 3-chloro-N-hydroxy-2-oxo-propylimino chloride.The present application uses divinyl ketone as raw material, through chlorination addition, hydrolysis, oximation and chloro step, and 3-chloro-N-hydroxy-2-oxo-propylimino chloride is prepared.By the preparation method of the present application, it solves the problems that raw material is not easy to obtain in original route, waste acid production is large, etc., is suitable for industrial production.
Owner:JINGBO AGROCHEM TECH CO LTD

A method for preparing methyl acetoacetate

ActiveCN116120176BTimely and effective dilutionStable and controllable temperatureOrganic compound preparationPreparation from ketenes/polyketenesPtru catalystAlcohol
The invention discloses a method for preparing methyl acetoacetate, and belongs to the field of chemical technology. The method of the invention comprises the following steps: firstly injecting methanol and a catalyst at a certain flow rate respectively, then using a pump to pump out the crude ester in a buffer tank at a certain flow rate, mixing it with an alcohol solution, and then injecting the diketene and alcohol ester mixed solution into a continuous flow reactor at a certain flow rate for reaction. The method of the invention circulates the crude ester during the continuous reaction process, which can timely and effectively dilute the heat generated by the reaction, and better solves the problem of heat accumulation in the reactor, inability to dissipate heat in time, and thus causing a rapid rise in temperature, reduces safety hazards, improves product quality and yield, and reduces the requirements for the temperature resistance of pipeline equipment.
Owner:NANTONG ACETIC ACID CHEM

Method for synthesizing high purity high myrcene

ActiveCN119798023BCycloadditionEthenone
The application provides a synthesis method of high-purity high-myrcene, comprising the following steps: carrying out [2+2] cycloaddition reaction of 8-methyl-2,7-nonadiene-4-ketone and ethenone to obtain a beta-lactone intermediate, and carrying out retro-cycloaddition reaction of the beta-lactone intermediate to obtain high-purity high-myrcene product. The synthesis route of the application is novel and short, high-myrcene is prepared simply and efficiently by taking simple and easily obtained 8-methyl-2,7-nonadiene-4-ketone and ethenone as raw materials through two-step reaction of cycloaddition and ring-opening, the overall yield of the route is high, compared with the traditional process of Grignard addition-dehydration method, the content of the target isomer is significantly improved, and the development of high-myrcene downstream derivatives is facilitated.
Owner:WANHUA CHEM GRP CO LTD +1

A process for the one-step synthesis of (r)-(-)-1,3-butanediol from diacetylene

The application discloses a method for synthesizing (R)-( - )-1,3-butanediol by a one-step method of diketene, which uses a chiral ruthenium complex as a catalyst and a Bronsted acid as an assistant to make the diketene react by a one-step method under certain temperature and hydrogen pressure conditions to obtain (R)-( - )-1,3-butanediol. The method solves the problems of high cost, large catalyst consumption and difficult product separation in the prior art for preparing (R)-( - )-1,3-butanediol, and can asymmetrically hydrogenate the carbonyl group of the substrate diketene at low cost and with a small amount of catalyst, simultaneously reduces the ester group and opens the ring to obtain (R)-( - )-1,3-butanediol. The method has simple reaction operation and simple catalyst preparation, the yield of the target product and ee value are both above 98%, meanwhile, the catalyst can be repeatedly used, the cost is greatly reduced, and the method has the potential for industrial application.
Owner:WANHUA CHEM GRP CO LTD

Fungicidal compositions comprising oxathiapiprolin derivatives

PCT designated stageWO2025195884A1BiocideFungicidesOxathiapiprolinPhenyl group
The present invention relates to fungicidal compositions comprising at least one compound selected from the group consisting (I-1) 2-[3,5-bis(trifluoromethyl)pyrazol-1-yl]-1-[4-[4-[5-[2-[[dimethyl(oxo)-λ⁶-sulfanylidene]amino]-6-fluoro- phenyl]-4,5-dihydroisoxazol-3-yl]thiazol-2-yl]-1-piperidyl]ethenone, (I-2) 2-[3,5-bis(difluoromethyl)pyrazol-1-yl]-1-[4-[4- [5-[2-chloro-6-[(isopropyl-methyl-oxo-λ⁶-sulfanylidene)amino]phenyl]-4,5-dihydroisoxazol-3-yl]thiazol-2-yl]-1- piperidyl]ethenone, (I-3) 2-[3,5-bis(trifluoromethyl)pyrazol-1-yl]-1-[4-[4-[5-[2-fluoro-6-[(isopropyl-methyl-oxo-λ⁶- sulfanylidene)amino]phenyl]-4,5-dihydroisoxazol-3-yl]thiazol-2-yl]-1-piperidyl]ethenone, (I-4) 2-[3,5- bis(difluoromethyl)pyrazol-1-yl]-1-[4-[4-[5-[2-[[dimethyl(oxo)-λ⁶-sulfanylidene]amino]-6-(trifluoromethyl)phenyl]-4,5- dihydroisoxazol-3-yl]thiazol-2-yl]-1-piperidyl]ethenone, (I-5) 1-[4-[4-[5-[2-fluoro-6-[(isopropyl-methyl-oxo-λ⁶- sulfanylidene)amino]phenyl]-4,5-dihydroisoxazol-3-yl]thiazol-2-yl]-1-piperidyl]-2-[5-methyl-3-(trifluoromethyl)pyrazol-1-yl]ethenone and at least one active compounds II. The invention also relates to an agrochemical composition comprising the composition and a solvent of solid carrier. Further, the invention relates to a non-therapeutic use of the inventive compositions controlling phytopathogenic harmful fungi.
Owner:BASF SE

Preparation method of cyclospice

The invention relates to a preparation method of cyclospice. According to the method, cyclooctene and ketene are taken as raw materials, acyl is introduced to the alpha position of double bonds under the illumination condition in the presence of a metal Ni catalyst and an organic phosphine ligand, and thus perfume molecules with a cyclooctene skeleton are synthesized. The perfume has native fragrance, natural fragrance, flower fragrance, green fragrance and costustoot, and can be applied to the field of high-end perfume and fragrance.
Owner:WANHUA CHEM GRP CO LTD +1

Continuous reaction research process for low-biphenylamine impurity 2, 4-dimethyl-bis-acetanilide

The invention discloses a continuous reaction research process of low-biphenylamine impurity 2, 4-dimethyl-bis-acetanilide, and belongs to the field of chemical synthesis. The invention aims to provide the continuous reaction research process for the low-bis-phenylamine impurity 2, 4-dimethyl-bis-acetanilide (2, 4-dimethyl-N-acetoacetanilide), the retention time of the 2, 4-dimethyl-N-acetoacetanilide raw material is shortened, the bis (2, 4-dimethyl phenyl) amine impurity is reduced, the yield of the 2, 4-dimethyl-N-acetoacetanilide is increased, and the production cost is reduced. Meanwhile, the auto-polymerization of the diketene is reduced, the consumption of the 2, 4-dimethylaniline is reduced, and the problems of high impurity content of the bis (2, 4-dimethylphenyl) amine in the existing 2, 4-dimethyl-N-acetoacetanilide and poor batch stability are solved.
Owner:NANTONG ACETIC ACID CHEM

Energy-saving diketene quencher

The invention discloses an energy-saving diketene quench cooler, which belongs to the technical field of quench coolers, and comprises a shell, the top and the bottom of the shell are respectively provided with a cooling liquid inlet and a cooling liquid outlet, and the left side and the right side of the shell are respectively provided with a material inlet and a material outlet; the fixing plates are fixed to the top and the bottom of the interior of the shell, heat exchange pipes penetrate through the interiors of the fixing plates at equal angles, a draught fan is installed on the outer wall of the shell, and the draught fan is connected with a cooling mechanism through the fixing pipes; and the adjusting mechanism is arranged in the heat exchange pipe, and the adjusting mechanism is used for adjusting the flow speed of the cooling liquid in the heat exchange pipe. According to the energy-saving diketene quench cooler, materials are cooled in the mode that cooling liquid and blowing are combined, the cooling efficiency can be improved, the cooling time can be shortened, and when the amount of the cooling liquid in the heat exchange pipes is the same, the flow speed of the cooling liquid can be adjusted according to the cooling requirement.
Owner:YANCHENG HUATI CHEM CO LTD

Method for preparing ketene by microwave-promoted acetic acid cracking dehydration

The invention discloses a method for preparing ketene by promoting cracking dehydration of acetic acid through microwaves. The method comprises the following steps: S1, mixing acetic acid and a polymerization inhibitor, and carrying out vaporization treatment to obtain raw material gas; s2, introducing the raw material gas into a microwave reaction device filled with a catalyst, and carrying out microwave cracking reaction to obtain ketene; wherein the time of the microwave cracking reaction is 5-20 seconds, and the microwave frequency of the microwave cracking reaction is 100-200 MHZ. The method provided by the invention has the characteristics of low energy consumption, high reaction speed, high selectivity, difficulty in side reaction, simple and convenient process flow and small occupied area of equipment when being used for preparing the key raw material ketene of sorbic acid.
Owner:GUANGDONG GUANGYI TECH IND

A process for the production of beta-butyrolactone by asymmetric hydrogenation of a diketene

The application provides a method for preparing beta-butyrolactone through asymmetric hydrogenation of diacetylene ketone, which is prepared through catalyzing asymmetric hydrogenation of diacetylene ketone under a hydrogen atmosphere by using a metal active component and a pyridine ring phosphine ligand as a catalyst. The method uses a hydroxyl-containing nitrogen heterocyclic phosphine ligand as a ligand, and a metal such as palladium, rhodium or ruthenium as an active metal, so that the conversion rate and selectivity of the reaction are improved, the stability of the catalyst is good, and the catalyst can be used multiple times. The synthesis route of the catalyst used in the method is short, the yield is high, the number of times of reusing is large, and the method has a good cost advantage.
Owner:WANHUA CHEM GRP CO LTD

Process for the one-pot preparation of sitagliptin intermediates

ActiveCN116947638BOrganic compound preparationPreparation from ketenes/polyketenesPhenylacetic acidThin layer chromatographic
The application belongs to the technical field of preparation of pharmaceutical intermediates, and particularly relates to a one-pot method for preparing a sitagliptin intermediate. The one-pot method for preparing the sitagliptin intermediate comprises the following steps: at room temperature, 2,4,5-trifluorophenylacetic acid is dissolved in an organic solvent A, the temperature is lowered to 0-5 DEG C, thionyl chloride is added dropwise, after the dropwise addition is completed, the temperature is raised to 25-30 DEG C, and reaction is carried out for 2 hours; thin layer chromatography analysis is used for monitoring; vacuum concentration is carried out; an intermediate oil is obtained; solvent B is added; ketene is charged; the temperature is lowered to -78 DEG C to room temperature; reaction is carried out for 3 hours; thin layer chromatography is used for monitoring; after the reaction is completed, the temperature is raised to room temperature; stirring is continuously carried out for 12 hours; water is added; the liquid is left to stand and is separated into layers; the organic phase is collected; extraction is carried out; rotary evaporation is carried out; and the sitagliptin intermediate II is obtained. The preparation method of the sitagliptin intermediate provided by the application has the advantages that raw materials are low in price and easy to obtain, reaction conditions are mild, industrial production can be easily realized, the prepared intermediate is high in purity and high in yield.
Owner:ZIBO FEIYUAN CHEM CO LTD

Continuous reaction research process for low-bis-phenylamine impurity-o-methoxy-bis-acetanilide

The invention discloses a continuous reaction research process of low-biphenylamine impurity o-methoxy-bis-acetanilide, and belongs to the field of chemical synthesis. Ethanol with a certain concentration is prepared in a condensation kettle for bottoming, o-methoxyaniline and diketene are controlled to be added into the kettle according to the equal molar ratio for rapid condensation reaction, liquid in the condensation kettle continuously overflows into a crystallization kettle for further reaction under the low-temperature condition, full reaction of raw materials is guaranteed, the product yield is increased, and the production cost is reduced. Conveying to a centrifugal machine by using a solid-liquid conveying pump for centrifugal washing, returning a centrifugal washing solution to the condensation kettle, and filtering and drying a wet product to obtain a finished product. According to the invention, through rapid reaction at a high temperature and quenching at a low temperature in the reaction kettle, the residence time of the o-methoxyaniline raw material is shortened, the bis (2-methoxyphenyl) amine impurity is reduced, the diketene auto-polymerization is reduced, and the consumption of o-methoxyaniline is reduced.
Owner:NANTONG ACETIC ACID CHEM

Synthesis method of high-purity homomyrcene

The invention provides a synthesis method of high-purity homomyrcene, which comprises the following steps: carrying out [2 + 2] cycloaddition reaction on 8-methyl-2, 7-nonadien-4-ketone and ketene to obtain a beta-lactone intermediate, and carrying out reverse cycloaddition reaction on the beta-lactone intermediate to obtain a high-purity homomyrcene product. According to the present invention, the synthesis route is novel and short, the simple and easily available 8-methyl-2, 7-nonadien-4-one and the ketene are adopted as the raw materials, the homomyrcene is simply, conveniently and efficiently prepared through the cycloaddition and ring opening two-step reaction, the overall yield of the route is high, and compared with the Grignard addition-dehydration method adopted by the traditional process, the content of the target isomer is significantly increased, and the yield of the homomyrcene is significantly improved; the development of high myrcene downstream derivatives is convenient.
Owner:WANHUA CHEM GRP CO LTD +1

An antioxidant polyvinyl alcohol derivative containing a 1,4-dihydropyridine structure, and a preparation method and applications thereof

The application provides an antioxidant polyvinyl alcohol derivative containing a 1,4-dihydropyridine structure and a preparation method and application thereof. The antioxidant polyvinyl alcohol derivative contains a 1,4-dihydropyridine structural unit, a vinyl alcohol structural unit and a vinyl acetate structural unit. The preparation method is as follows: polyvinyl alcohol is dissolved in anhydrous organic solvent, divinyl ketone is added for reaction to obtain a polyvinyl alcohol derivative containing a beta-diketone, in the presence of a catalyst, an aldehyde compound, an ammonia source compound and a 1,3-diketone compound are added into the obtained polyvinyl alcohol derivative containing a beta-diketone for Hantzsch reaction to obtain the antioxidant polyvinyl alcohol derivative containing the 1,4-dihydropyridine structure. The prepared polyvinyl alcohol derivative has excellent antioxidant performance and can be applied to the fields of food packaging, biological medicine, health care and the like.
Owner:CHINA PETROLEUM & CHEMICAL CORP +2

Evaporation and impurity removal equipment for acetic acid in diketene production

The invention relates to the technical field of impurity removal equipment, in particular to acetic acid evaporation impurity removal equipment in ketene dimer production, which comprises an impurity removal bin, a cover plate, a first flange, a second flange, an adjusting device, a connecting device and a supporting structure, four placing grooves are formed in the annular outer wall surface of the impurity removal bin at the same rotation angle, and the four placing grooves are arranged in the extending direction of the impurity removal bin. The four vent grooves correspond to and communicate with the four containing grooves respectively, the four cover plates are detachably installed on the annular outer wall of the impurity removal bin through bolts, the first flange is fixedly installed at the first end of the impurity removal bin, and the second flange is fixedly installed at the second end of the impurity removal bin. Gas passes through the two sections of gas grooves in a reciprocating manner within a fixed distance, so that the time and contact area of the gas passing through the filter element are increased, and the filtering effect is improved; different substances can be filtered by dismounting and mounting different filter elements and adjusting a gas flowing channel, so that the applicability and functionality of the equipment are improved.
Owner:YANCHENG HUATI CHEM CO LTD

Device and process method for recovering tail gas of diketene rectification vacuum pump

The invention belongs to the technical field of ketene dimer production, and particularly relates to a device and a process method for recovering tail gas of a ketene dimer rectification vacuum pump. According to the device, a rectifying still is connected with the top of a rectifying buffer tank through a pipeline, the rectifying buffer tank is connected with the top end of a rectifying oil tank through a pipeline, the rectifying oil tank is connected with a rectifying vacuum pump in series through a pipeline, the rectifying vacuum pump is connected with a rectifying activated carbon tank through a pipeline, and the rectifying activated carbon tank is connected with a rectifying bath tower through a pipeline. The rectification water scrubber is connected to a rectification water seal through a pipeline, and the rectification water seal is connected with the cracking furnace through a pipeline. The process method comprises the following steps: tail gas at an outlet in the operation process of a rectification vacuum pump sequentially enters a rectification activated carbon tank, a rectification water washing tower, a rectification water seal and a cracking furnace through pipelines for combustion and decomposition. The tail gas reaches the standard, meanwhile, fuel is saved, and finally energy conservation and emission reduction are achieved.
Owner:ANHUI JINHE INDUSTRIAL CO LTD

Method for preparing a polymer having ester functionality and said polymer prepared therefrom

PendingUS20250179252A1MethacrylatePolymer science
There is provided a method for preparing a polymer having ester functionality in the backbone of the polymer, the method comprising a step of reacting a mixture of monomers that comprises: (i) at least one first acrylate and / or methacrylate monomer; (ii) at least one cyclic ketene acetal monomer; and (iii) at least one additional monomer selected from the group consisting of a second acrylate and / or methacrylate monomer that is functionalized with hydrophilic groups, a vinylic monomer that is functionalized with hydrophilic groups, and combinations thereof in aqueous media to obtain the polymer. There is also provided a polymer having ester functionality in the backbone of the polymer obtained from said method.
Owner:AGENCY FOR SCI TECH & RES

A process for the preparation of a phenylacetyl acetic acid compound

The application discloses a preparation method of a phenylacetyl acetic acid compound, relates to the technical field of chemical synthesis, and the synthesis route of the phenylacetyl acetyl acid compound is as follows: an aniline compound connected with five groups of R1, R2, R3, R4 and R5 is used as a raw material, a diazotization reagent is added under acidic conditions to perform a diazotization reaction, a phase transfer catalyst, a copper catalyst and divinyl ketone are added to perform a reaction, and hydrolysis is performed under acidic conditions to obtain the phenylacetyl acetic acid compound; wherein R1, R2, R3, R4 and R5 are each independently selected from F, Cl, Br, -CH3, -OCH3, NO2, -C2H5, -C3H7, -CF3 or H, and are not H at the same time; when one or more of R1, R2, R3, R4 and R5 is F, the rest are not all H; and X is selected from Cl or Br. The raw material prepared by the application is easy to obtain, the operation is simple, the reaction condition is mild, the danger is low, the reaction step is short, the production cost and three waste emissions of enterprises are reduced, and large-scale industrial production can be easily realized.
Owner:TAIZHOU ABSOBIOTEC CO LTD

Preparation method of nickel-based catalyst and chiral beta-butyrolactone

The invention provides a method for synthesizing chiral beta-butyrolactone. The method comprises the step of catalyzing asymmetric hydrogenation of diketene by using a catalyst prepared from a diphosphine ligand and a nickel metal precursor in situ in the presence of a weakly alkaline additive to prepare the chiral beta-butyrolactone. The method solves the problem of low catalyst activity caused by byproducts of diketene asymmetric hydrogenation reaction, and is relatively mild in reaction condition, simple to operate, low in catalyst cost, wide in substrate application range and high in enantioselectivity.
Owner:WANHUA CHEM GRP CO LTD

Synthesis method and synthesis system of epsilon-caprolactone

The invention discloses a synthesis method and a synthesis system of epsilon-caprolactone, and belongs to the technical field of chemical engineering. According to the synthesis method disclosed by the invention, tetrahydrofuran and ketene are taken as raw materials and are subjected to nucleophilic addition reaction under the action of a basic catalyst to generate epsilon-caprolactone. The synthesis system comprises a ketene reactor, a recovery tower and a lactone refining tower which are connected in sequence, the ketene reactor is connected with a raw material gas mixture conveying pipe, and the lactone refining tower is connected with an epsilon-caprolactone product output pipe; and a catalyst bed layer is arranged in the ketene reactor. According to the method, the energy consumption of the device and the cost of raw materials are reduced, the yield of byproducts is reduced, the treatment difficulty of three wastes is reduced, and the safety risk problem of peroxide decomposition in the production process of a traditional process is solved.
Owner:CHINA CHENGDA ENG

Low-temperature preparation method of ketene

PendingCN121226142AKetenes preparationNitrogen oxidesEthylic acid
The invention relates to the technical field of chemical production, and provides a low-temperature preparation method of ketene. According to the method, the high-activity auxiliary is added in the acetic acid cracking process to initiate the acetic acid cracking reaction, so that the cracking temperature is reduced, the side reaction is reduced, the selectivity of ketene is improved, and the energy consumption is reduced; meanwhile, nitrogen oxide and the like generated after the aid is decomposed at high temperature have polymerization inhibition effect, so that the auto-polymerization of the gas-phase ketene can be prevented, the problem that the ketene is difficult to store is solved, and the effect of'one agent with double effects' is realized.
Owner:HANGZHOU WEIYING NEW MATERIALS CO LTD

Cooling device for acetic anhydride production

This invention provides a cooling device for acetic anhydride production, including a cooling cylinder. The lower end of the cooling cylinder has a gas inlet pipe and a support, while the upper end has a gas outlet pipe. Inside the cooling cylinder, along its axis, are a primary spiral coil and a secondary spiral coil. Both the primary and secondary spiral coils have water inlets at one end and water outlets at the other. The lower end of the primary spiral coil has a primary swirl vane, and a secondary swirl vane is located between the primary and secondary spiral coils. This invention utilizes gradient cooling through two stages of variable-diameter spiral coils, combined with two stages of swirl vanes to enhance the turbulence of high-temperature ketene gas, significantly improving the cooling efficiency of ketene gas and reducing energy consumption, making it suitable for continuous industrial production.
Owner:MENGZHOU DINGXING CHEM CO LTD

A process for the preparation of 6-ethylthio-3-hepten-2-one

The present application relates to the technical field of chemical synthesis, especially to IPC C07C323, more particularly to a method for preparing 6-ethylsulfanyl-3-heptene-2-ketone, which comprises the following steps: mixing 3-ethylsulfanyl butyraldehyde, water and a catalyst, adding dropwise divinyl ketone at 25-35 DEG C, keeping warm for 7-10 hours, adding acid to dehydrate, washing with alkali after the reaction is completed, and vacuum desolventizing to obtain 6-ethylsulfanyl-3-heptene-2-ketone. The present application uses 3-ethylsulfanyl butyraldehyde, divinyl ketone, a catalyst and water as raw materials, has low energy consumption, and will not produce wastewater containing sodium acetate, methanol and acetone.
Owner:SHOUJIAN TECH CO LTD