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160 results about "Elimination reaction" patented technology

An elimination reaction is a type of organic reaction in which two substituents are removed from a molecule in either a one or two-step mechanism. The one-step mechanism is known as the E2 reaction, and the two-step mechanism is known as the E1 reaction. The numbers refer not to the number of steps in the mechanism, but rather to the kinetics of the reaction: E2 is bimolecular (second-order) while E1 is unimolecular (first-order). In cases where the molecule is able to stabilize an anion but possesses a poor leaving group, a third type of reaction, E1CB, exists. Finally, the pyrolysis of xanthate and acetate esters proceed through an "internal" elimination mechanism, the Eᵢ mechanism.

Alpha, omega-diiodo perfluoroalkane derivative, alpha, omega-diiodo ethyl perfluoroalkane derivative, and preparation method and application of alpha, omega-diiodo perfluoroalkane derivative

The invention discloses an alpha, omega-diiodo perfluoroalkane derivative, an alpha, omega-diiodo ethyl perfluoroalkane derivative as well as a preparation method and application of the alpha, omega-diiodo perfluoroalkane derivative and the alpha, omega-diiodo ethyl perfluoroalkane derivative. According to the method, alpha, omega-diiodo perfluoroalkane is taken as a raw material, and the alpha, omega-diiodo perfluoroalkane and ethylene are subjected to free radical addition reaction under the action of an initiator and a solvent to prepare the alpha, omega-diiodo ethyl perfluoroalkane. The alpha, omega-diiodoethyl perfluoroalkane and alkali are subjected to a one-molecule and / or two-molecule hydrogen iodide hydride elimination reaction, and alpha, omega-iodoethyl vinyl perfluoroalkane and / or alpha, omega-divinyl perfluoroalkane are / is generated. The method is simple and convenient to operate, the raw material utilization rate and the target product yield are high, the preparation cost is effectively reduced, and the industrial production requirement is met. The alpha, omega-diiodo perfluoroalkane derivative or alpha, omega-diiodo ethyl perfluoroalkane derivative prepared by the method disclosed by the invention can be used as a vulcanization point monomer for preparing peroxide vulcanized fluororubber, and compared with common rubber, the rubber has more excellent compression deformation performance, strength and medium resistance and has a wide application prospect.
Owner:JUHUA GROUP TECH CENT +1

Non-silicon defoaming agent, synthetic method and application in field of scandium extraction

The invention discloses a synthesis method of a non-silicon defoaming agent and application of the non-silicon defoaming agent in the field of scandium extraction in hydrometallurgy. The defoaming agent is synthesized by a component A, a component B and a component C through a two-step reaction, the synthesis method comprises the following specific synthesis steps: 1) carrying out esterification reaction on an amino acid substance A and a fatty alcohol substance B to generate an amino ester substance D; and 2) carrying out substitution reaction on the amino ester substance D and a triazine compound C to obtain the non-silicon defoaming agent. The defoaming agent disclosed by the invention is wide in application range, can be applied to links such as a laterite-nickel ore hydrometallurgy front-end scandium extraction method and an MHP hydrometallurgy scandium impurity removal process, is added as an auxiliary agent in the extraction process, and is used for reducing the surface tension of liquid, preventing the formation and enrichment of a third-phase substance and reducing the occurrence of an emulsification phenomenon; the process stability and the output quality are improved, and the method has important industrial application value.
Owner:WANHUA CHEM GRP CO LTD

Method for producing hexafluorobutadiene, continuous production system and application thereof

The invention relates to the technical field of organic chemical synthesis, and particularly discloses a method for producing hexafluorobutadiene, a continuous production system and application thereof. The method for producing hexafluorobutadiene comprises the following steps: (1) bromination reaction: reacting tetrafluoroethylene with liquid bromine to generate dibromotetrafluoroethane; (2) telomerization reaction: reacting the dibromo tetrafluoroethane with tetrafluoroethylene under the action of a catalyst to generate dibromo octafluorobutane; the catalyst is cuprous bromide; and (3) elimination reaction: reacting the dibromo octafluorobutane under the action of a Grignard reagent to generate hexafluorobutadiene. The method provided by the invention has the advantages of simple process, easily available raw materials, high production efficiency, continuous production, low production cost and industrial mass production value.
Owner:ZHONGHAO CHENGUANG RES INST OF CHEMICALINDUSTRY CO LTD

Ultrasonic activated azido precursor, prodrug and application

The invention provides an ultrasonic activated azido precursor, a prodrug and application. The precursor and an active drug react and are bonded to obtain the azido prodrug; the bonding group of the active medicine is amino, hydroxyl or sulfydryl; a bonding group of the ultrasonic activated azido precursor is an ester group. Novel ultrasonic activatable groups, namely p-azidobenzyloxycarbonyl and derivatives thereof, are adopted, hydrogen atoms on a benzene ring are substituted to different degrees, the reducing capacity of a precursor can be remarkably improved, azide is effectively reduced into amino through ultrasonic stimulation under the action of TBR and NADH, and then a self-elimination reaction is induced to release active drugs. The structure has the advantages that different types of active drugs (active pharmacodynamic groups can be amino, hydroxyl and sulfydryl) can be bonded through 4-nitrophenyl carbonate, high-selectivity reduction is performed under the triple action of ultrasound, TBR and NADH, active raw drugs are released according to needs, and toxicity reduction and synergism are achieved.
Owner:CHANGCHUN INSTITUTE OF APPLIED CHEMISTRY CHINESE ACADEMY OF SCIENCES

Preparation method for parylene-series product and parylene-series product

PCT designated stage expiredWO2025044634A1HydrocarbonsHydrocarbon preparationPolymer sciencePtru catalyst
A preparation method for a parylene-series product, and a parylene-series product. The preparation method for a parylene-series product comprises the following steps: S1, reacting a compound 1 and a compound 2 with N,N,N',N'-tetramethyldiaminomethane to obtain diquaternary ammonium salt; and S2, carrying out an elimination reaction on the diquaternary ammonium salt and a catalyst under an alkaline condition to obtain a parylene-series product as shown in general formula (I), wherein the structural formulas of the compound 1, the compound 2 and the diquaternary ammonium salt are as shown in general formulas (II), (III) and (IV), respectively. Various benzyl halides are reacted with N,N,N',N'-tetramethyldiaminomethane to obtain diquaternary ammonium salt having a linker arm, and a p-quinodimethane intermediate state is formed, so that the intermediate state is prevented from being linked end to end to generate a linear polymerization side reaction, and the parylene-series product can be efficiently prepared.
Owner:SUZHOU YACOO SCI CO LTD +1

Synthetic method of indaziflam intermediate 2, 6-dimethyl-indene amine

The invention discloses a synthesis method of an indaziflam intermediate 2, 6-dimethyl-indene amine. In the invention, indanone is reduced by using a cheap reducing reagent to prepare indanol, the indanol and sulfonyl chloride are subjected to an elimination reaction to prepare indene, and finally, the indene and an amination reagent are subjected to addition to prepare the 2, 6-dimethyl-indene amine. The route is good in reaction selectivity and few in side reaction, and the total yield of the 2, 6-dimethyl-indene amine can reach 70% or above. The method is mild in reaction condition, easy to control, less in three wastes, simple in whole process operation and easy to industrialize.
Owner:ANHUI RES INST OF CHEM IND

Synthesis method of 3-oxo-1-cyclobutyl carboxylic acid

The invention discloses a novel method for synthesizing 3-oxo-1-cyclobutanecarboxylic acid, which comprises the following steps: taking dichloroacetyl chloride or trichloroacetyl chloride as a starting raw material, carrying out elimination reaction in a solvent under the catalytic action of alkali or Zn-Cu, and reacting the obtained dichloroketene intermediate with methyl acrylate in situ to generate 3-oxo-2, 2, 3-trimethyl-1-cyclobutanecarboxylic acid, thereby obtaining the 3-oxo-1-cyclobutanecarboxylic acid. The 3-oxo-1-cyclobutanecarboxylic acid is prepared by using 2, 2-dichloro-1-cyclobutanecarboxylic acid as a raw material, then dehalogenation and hydrolysis reactions are carried out to prepare the 3-oxo-1-cyclobutanecarboxylic acid, the 3-oxo-1-cyclobutanecarboxylic acid is a pure product with the content of 99% or above, and the total yield reaches 50% or above. The synthetic route has the advantages of mild conditions, few byproducts, high yield and environmental friendliness, and is suitable for industrial amplification.
Owner:DALIAN RES & DESIGN INST OF CHEM IND

Preparation method of 6-benzofuran phenol

The invention provides a preparation method of 6-benzofuran phenol, which comprises the following steps: step S1, 6-hydroxy-2H-benzofuran-3-ketone and a methylation reagent are subjected to a reaction to generate 6-hydroxymethyl-2H-benzofuran-3-ketone, and the methylation reagent is one or more of dimethyl sulfate, methyl iodide, dimethyl carbonate and the like; step S2, enabling the 6-hydroxymethyl-2H-benzofuran-3-ketone to react with a reducing agent, so as to generate 6-hydroxymethyl-2H-benzofuran-3-alcohol; s3, the 6-hydroxymethyl-2H-benzofuran-3-alcohol is subjected to a demethylation reaction and an elimination reaction, and the 6-benzofuran phenol is generated. According to the preparation method of the 6-benzofuran phenol, the phenolic hydroxyl group is protected by methyl, demethylation and alcohol elimination are completed by a one-pot method, and an intermediate product has few impurities and is simple to purify.
Owner:ANHUI HIGHFINE BIOTECH CO LTD

Synthesis method of glyphosate

The invention discloses a synthesis method of glyphosate. The synthesis method comprises the following steps: carrying out a depolymerization reaction on paraformaldehyde, formaldehyde and a catalyst in methanol to obtain a depolymerization solution; adding glycine, methanol and triethylamine into the depolymerization liquid for catalytic reaction to obtain addition liquid; dimethyl phosphite is added into the addition liquid, triethylamine is supplemented, and a condensation liquid is obtained through a reaction; adding the condensation liquid into a supercritical extraction kettle, and extracting methanol and triethylamine hydrochloride; and adding hydrochloric acid into the extracted condensation liquid for acidolysis to remove chloromethane, hydrogen chloride, water or other light components, adding alkali to adjust pH, crystallizing, filtering and drying to obtain glyphosate. According to the method, a typical glycine method production process is improved, methanol, triethylamine hydrochloride and water in condensation reaction liquid can be quickly removed at low temperature by adopting a supercritical extraction technology, acidolysis energy consumption and hydrochloric acid consumption are reduced, a removed triethylamine and methanol mixed solution is recycled, and the yield of the product is improved. And the effects of recycling resources and reducing energy consumption are achieved. Meanwhile, the catalyst B is added, so that free aldehyde in a reaction system can be eliminated, side reactions are reduced, and the quality of the glyphosate active compound is improved.
Owner:HUBEI TAISHENG CHEM

Dialkene fluorine-containing vulcanization point monomer as well as synthesis method and application thereof

The invention belongs to the technical field of fluorine chemical industry, and particularly relates to a diolefin fluorine-containing vulcanization point monomer and a synthesis method and application thereof, the diolefin fluorine-containing vulcanization point monomer has a structural general formula as shown in formula (I): # imgabs0 #, in the formula, n is a positive integer; the synthesis method comprises the following steps: step 1, in a solvent, mixing perfluorodiiodoalkane with a free radical initiator, then introducing ethylene, and carrying out an addition reaction to obtain an intermediate product; and 2, mixing the intermediate product obtained in the step 1 with an inorganic base, and carrying out an elimination reaction to obtain the diene fluorine-containing vulcanization point monomer. Compared with the prior art, the invention solves the problems of complexity and low efficiency of the synthesis method of the diolefin fluorine-containing vulcanization point monomer in the prior art, and realizes rapid and convenient synthesis of the diolefin fluorine-containing vulcanization point monomer.
Owner:SHANGHAI 3F NEW MATERIAL TECH CO LTD

Preparation method of chloromethyl styrene

The invention provides a method for preparing p-chloromethyl styrene, which comprises the following steps: (1) in the presence of a catalyst and an assistant, carrying out reaction on paraformaldehyde and hydrogen chloride to obtain a chloromethylation reagent; (2) reacting beta-halogenated ethyl benzene with the chloromethylation reagent obtained in the step (1) to obtain chloromethyl halogenated ethyl benzene; (3) adding an extracting agent into the chloromethyl halogenated ethylbenzene reaction liquid obtained in the step (2) for extraction to obtain an oil layer containing chloromethyl halogenated ethylbenzene and a water-containing acid layer, and crystallizing the oil layer to obtain purified p-chloromethyl halogenated ethylbenzene; and (4) in the presence of a solvent, carrying out elimination reaction on the purified p-chloromethyl halogenated ethyl benzene and alkali to obtain p-chloromethyl styrene.
Owner:JIANGSU YANGNONG CHEMICAL GROUP CO LTD

Preparation method of 11 beta, 17 alpha-dihydroxy-6 alpha-methylpregna-4-ene-3, 20-diketone

The invention relates to the technical field of pharmaceutical chemicals, in particular to a preparation method of 11beta, 17alpha-dyhydroxyl-6 alpha-methylpregna-4-ene-3, 20-diketone, and discloses a preparation method of 11beta, 17alpha-dyhydroxyl-6 alpha-methylpregna-4-ene-3, 20-diketone. The method comprises the following steps: S1, adding a 11beta, 17alpha-dyhydroxyl-6 alpha-methylpregna-4-ene-3, 20-diketone crude product into a mixed solution of a solvent A and a solvent B, heating to 25-35 DEG C, and stirring for dissolving until the solution is clear, so as to obtain a 11beta, 17alpha-dyhydroxyl-6 alpha-methylpregna-4-ene-3, 20-diketone crude product; s2, carrying out transposition elimination reaction; s3, carrying out acidification deprotection reaction; s4, adjusting the pH value; s5, standing and layering; s6, decoloring; s7, performing concentration; s8, cooling and crystallizing; s9, carrying out solid-liquid separation; and S10, carrying out vacuum drying, so as to obtain a finished product of the 11beta, 17alpha-dyhydroxyl-6 alpha-methyl pregna-4-ene-3, 20-diketone. The method has the characteristics of high yield and good product quality, is stable and is easy to realize industrial production.
Owner:SHANDONG SIRUI BIOPHARMACEUTICAL CO LTD +1

Synthesis method of alfasalone intermediate and synthesis method of alfasalone

The invention discloses a synthetic method of an alfasalone intermediate and a synthetic method of alfasalone, the synthetic method of the alfasalone intermediate comprises the following steps: carrying out hydrogenation reaction on a compound IN-2 to obtain a compound I, the hydrogenation condition is that a solvent ethanol or acetic acid and palladium on carbon are added, and the addition volume of the ethanol or acetic acid is 10-80 times of the weight of the IN-2; the synthesis method of the alfasalone comprises the following steps: carrying out elimination reaction on a compound SM to obtain an intermediate IN-1; performing ketal protection reaction on the intermediate IN-1 to obtain an intermediate IN-2; carrying out hydrogenation reaction on the intermediate IN-2 to obtain a compound I; carrying out ketal removal protection reaction on the compound I to obtain an intermediate IN-3; the intermediate IN-3 is subjected to carbonyl reduction through an enzyme method to obtain alfasalone; by exploring the reaction raw materials, the reaction solvent, the solvent addition amount, the reaction time and the like in the synthesis process of the alfasalone, the obtained product is high in yield and purity, and the industrial production of the alfasalone is realized.
Owner:HUNAN KYF PHARM CO LTD

Chloromethylation catalyst, preparation method and method for preparing high-purity ortho-position, meta-position and para-position chloromethyl styrene by using chloromethylation catalyst

The invention relates to the technical field of catalytic synthesis, in particular to a chloromethylation catalyst, a preparation method of the chloromethylation catalyst and a method for preparing high-purity ortho-position, meta-position and para-position chloromethyl styrene through the chloromethylation catalyst, and the chloromethylation catalyst is prepared by loading sulfonic acid compounds and (or) pyridine compounds and (or) copper salt on a molecular sieve. The method can improve the localization selectivity of chloromethylation. The method for preparing high-purity ortho-position, meta-position and para-position chloromethyl styrene comprises the following steps of: reacting beta-bromophenylethane, paraformaldehyde and lewis acid in the presence of the chloromethylation catalyst to generate chloromethyl beta-bromophenylethane, and then performing elimination reaction under an alkaline condition to generate a chloromethyl styrene crude product; the high-purity ortho-position, meta-position and para-position chloromethyl styrene is obtained after the crude product is rectified, the brand-new catalyst is adopted in the method, the reaction selectivity is enhanced, the process is simple, and industrial production is facilitated.
Owner:NANJING MAIN LIFE TECH CO LTD

Synthesis method of piperonone

The invention discloses a synthesis method of piperonone, and relates to the technical field of flavors, fragrances and chemical engineering, and the synthesis method comprises the following steps: taking acrylate as a raw material, and carrying out Michael addition reaction with isobutene under the action of Lewis acid to obtain 5-methyl-5-hexenoic acid ethyl ester; the preparation method comprises the following steps: carrying out nucleophilic substitution reaction on ethyl 5-methyl-5-hexenoate and bromoisopropane under the action of a basic catalyst to obtain ethyl 5-methyl-2-isopropyl-5-hexenoate; carrying out self Friedel-Crafts acylation reaction on the 5-methyl-2-isopropyl-5-hexenoic acid ethyl ester under the action of Lewis acid, so as to obtain 5-methyl-2-isopropyl-5-chloro cyclohexanone; and carrying out elimination reaction on the 5-methyl-2-isopropyl-5-chlorocyclohexanone under the action of alkali to obtain the product piperonone. According to the synthetic route, conventional chemical reagents are used as raw materials, reaction conditions are mild, emission of three wastes is reduced to a great extent, and the synthetic route is more environmentally friendly and suitable for continuous industrial production.
Owner:SICHUAN BOYUEHUI BIOTECHNOLOGY CO LTD

Preparation method of high-purity pyromellitic dianhydride

The application provides a preparation method of high-purity pyromellitic dianhydride, which is prepared from 2,3-dichloromaleic anhydride as raw material, and sequentially subjected to Diels-Alder cycloaddition reaction, elimination reaction and oxidation reaction to obtain high-purity pyromellitic acid, and then subjected to dehydration treatment to obtain high-purity pyromellitic dianhydride. In the preparation method, pyromellitic acid is used as a dehydration raw material to prepare anhydride, so that intermediate acid by-products are not easy to be generated, and the product purity is improved; the dehydration reaction is promoted by adopting azeotropic distillation and separation coupling, so that the reaction yield is improved; the preparation steps are few, the reaction process is simple, the reaction condition is mild, the raw materials are economically inexpensive and easy to obtain; the catalyst or the aid used in each step does not generate harmful substances, and is green and environment-friendly.
Owner:YINGKOU XINGFU CHEM CO LTD

Preparation method of rocuronium bromide intermediate 5 alpha-androstane-2-ene-17 ketone

The invention relates to an industrial preparation method of an intermediate 5alpha-androstane-2-ene-17 ketone, the intermediate is a rocuronium bromide intermediate, and the method comprises the following steps: taking epiandrosterone as a starting material, and reacting with paratoluensulfonyl chloride to obtain a compound I; and carrying out elimination reaction on the compound I in organic alkali or a DBU catalyst to obtain the compound 5 alpha-androstane-2-ene-17 ketone. The method is good in elimination reaction selectivity, high in yield, good in quality, low in cost, mild in reaction condition, short in production period, recyclable in reaction solvent and green and environment-friendly in production process, and a single impurity of the product is less than 0.3%.
Owner:重庆凯林制药有限公司 +1

Full continuous-flow preparation method of (+)-biotin

A full continuous-flow preparation method of (+)-biotin, including: subjecting a cyclic anhydride and a chiral biphenyl propylene glycol to asymmetric ring-opening reaction to produce a first intermediate, which undergoes selective reduction with a borohydride and cyclization with an inorganic mineral acid to produce (3aS, 6aR)-lactone; subjecting the (3aS, 6aR)-lactone and a sulfenylating reagent to sulfenylation to produce (3aS, 6aR)-thiolactone, which undergoes Fukuyama coupling with a zinc reagent in the presence of a palladium catalyst and elimination reaction in the presence of an inorganic mineral acid to produce an alkenyl valerate compound; subjecting the alkenyl valerate compound to reduction in the presence of a Pd / C catalyst to produce a valerate ester, which undergoes hydrolysis to produce a valeric acid salt; and subjecting the valeric acid salt to debenzylation in the presence of an inorganic mineral acid to produce the target product (+)-biotin.
Owner:FUDAN UNIVERSITY

Isatin hydrazone-pyrazole Schiff base dual-response fluorescent probe and preparation method thereof

The invention discloses a preparation method of a dual-response fluorescent probe based on an isatin hydrazone-pyrazole Schiff base structure, the dual-response fluorescent probe is synthesized by carrying out nucleophilic addition-elimination reaction on amino-functionalized isatin hydrazone and aldehyde group modified pyrazole, and the chemical structural formula of the dual-response fluorescent probe is as follows: # imgabs0 #. The probe disclosed by the invention has high specific recognition capability on Cu < 2 + > and CN <->. The probe shows fluorescence quenching response to Cu < 2 + >, the response time is short, and the anti-interference capability is strong. The probe realizes selective recognition of CN <-> in a fluorescence'opening 'mode, and shows a dual recognition signal of CN <-> along with obvious solution color change.
Owner:HENAN UNIVERSITY

Method for preparing halogenated fluorine-containing olefin with high yield and product and application thereof

The invention discloses a method for preparing halogenated fluorine-containing olefin with high yield as well as a product and application of the halogenated fluorine-containing olefin, dihalogenated perfluoroethane (ICF2CF2I or BrCF2CF2Br) and ethylene are taken as raw materials, under the action of a peroxide initiator TAPP (tert-amyl peroxypivalate, the addition amount of which is 0.2%-0.3% of the weight of the perfluorinated halogenated ethane), the ethylene is continuously introduced to maintain the reaction pressure of 0-5 kg, and the halogenated fluorine-containing olefin with high yield is prepared. Carrying out addition reaction to generate a dihalogenated fluorine-containing alkane intermediate; and heating toluene and sodium hydroxide / potassium hydroxide to 60-80 DEG C in a three-neck flask, superposing the intermediate to carry out elimination reaction, and continuously collecting the generated olefin through a distillation head to finally obtain ICF2CF2CH = CH2 or BrCF2CF2CH = CH2. The method is strong in process controllability, high in ethylene utilization rate and high in product separation efficiency, and adapts to iodination and bromination double-system production.
Owner:FUJIAN KERUN CENTURY HYDROGEN ENERGY MATERIAL CO LTD

A method for synthesizing a carboxyl-unprotected dihydrogibberellin plant growth regulator

The application discloses a new method for synthesizing dihydrogibberellin without protecting carboxyl. The application provides a new method for synthesizing dihydrogibberellin without protecting carboxyl, which comprises the following steps: 1) mixing a compound shown in formula II with a catalyst A in an organic solvent B, and carrying out a hydrogen reduction reaction under a hydrogen atmosphere to obtain a compound shown in formula III; 2) mixing the compound shown in formula III with a saturated aqueous solution of a base in an organic solvent C, and carrying out a selective deacetylation reaction to obtain a compound shown in formula IV; and 3) mixing the compound shown in formula IV with triphenyl phosphine and an elimination reagent in an organic solvent D, and carrying out a dehydration elimination reaction to obtain dihydrogibberellin shown in formula V. The application can simplify the synthesis method of dihydrogibberellin and is more beneficial to large-scale production and synthesis.
Owner:CHINA AGRI UNIV

Process for preparing benzoic acid esters and their intermediates

The present invention relates to a compound of formula (I), a pharmaceutically or cosmetically acceptable salt thereof, or any stereoisomer thereof, wherein R’ is selected from the group consisting of H, (C1-C6)-alkyl, and (C3-C6)-cycloalkyl; R1, R2, R4, R5, R6, R7, R9, and R 10 are independently radicals selected from the group consisting of H, hydroxy, amino, (C1-C6)-alkyl, (C1-C6)-alkoxy, (C1-C6)-alkylamino, and (C1-C6)-dialkylamino; R3 and R8 are independently selected from the group consisting of (C1-C6)-alkyl, (C1-C6)-alkoxy, hydroxy, amino, (C1-C6)-alkylamino, and (C1-C6)-dialkylamino), and relates to a process for preparing the same, which process comprises a beta-elimination reaction of the corresponding alkyl halide precursor in the presence of DBU and a suitable solvent. The present invention also relates to intermediates useful in such a preparation process. [Chemical 1] TIFF2025522152000022.tif95160
Owner:ロカフラダダエスエル

Preparation method of intermediate of macloxvir

The invention discloses a preparation method of an intermediate of macloxvir. The preparation method comprises the following steps: step 1, carrying out halogenation reaction; step 2, elimination reaction; step 3, addition reaction; step 4, ring closing reaction; the starting raw materials, the solvent and the catalyst selected in the invention are industrial-grade cheap and easily available products, have the advantage of low production raw material cost, and provide economic feasibility support for industrial large-scale production; reaction conditions of each step in the reaction process are mild, byproducts are few, the yield is high, and a target product can be prepared more efficiently; meanwhile, the synthesis route is high in atom utilization rate and excellent in atom economy, the used solvent and reagent are high in stability and easy to recycle and reuse, generation and emission of industrial three wastes are greatly reduced, the environment-friendly treatment cost is reduced, and the concept of green chemistry and sustainable development is met; the method gives consideration to economy, high efficiency and environmental friendliness, and solves the problems of low yield, violent reaction conditions and high cost of raw materials and auxiliary materials in the existing method.
Owner:SHANGHAI WOYING BIOTECHNOLOGY CO LTD

Synthesis method of atavapam

The invention provides a synthesis method of atavapam, which comprises the following steps: carrying out nucleophilic addition-elimination reaction on commercially available raw materials and 4-methyl-3-trifluoromethylaniline under alkaline conditions, carrying out Suzuki coupling reaction under the action of a catalyst, carrying out pressurized hydrogenation, and carrying out chiral resolution, thereby obtaining the atavapam. And condensing with 2-fluoro-6-methyl benzoyl chloride under an alkaline condition, and further removing a Boc protecting group under an acidic condition to finish synthesis of the atavapam. According to the invention, a convergent synthesis process is adopted, tedious synthesis steps in the original process are shortened, and post-treatment is simpler and more controllable.
Owner:HANGZHOU NUOAO BIOMEDICAL TECH CO LTD

Process for the preparation of dydrogesterone

ActiveCN117645644BBenzoic acidPtru catalyst
The application provides a preparation method of dydrogesterone, which comprises the following steps: performing a selective epoxidation reaction on a compound I in a first solution containing meta-chloroperoxybenzoic acid and hydrogen peroxide to obtain a compound II; the content of the meta-chloroperoxybenzoic acid in the first solution is more than 1 times of the amount of substance of the compound I; performing a reduction reaction on the compound II under the action of hydrogen and a catalyst to obtain a compound III; performing a hydrolysis reaction on the compound III in a dilute acid solution, and then performing a hydroxyl elimination reaction on the compound III in a second solution to obtain the dydrogesterone; the structural formulae of the compound I, the compound II, the compound III and the dydrogesterone are as follows:; and. The preparation method has less by-products and a higher reaction yield.
Owner:HUNAN KYF PHARM CO LTD

PROCESS FOR PREPARING beta-FARNESENES AND 2-(3-ALKENYL)-1,3-BUTADIENE COMPOUND HAVING RELATED STRUCTURE, AND SYNTHETIC INTERMEDIATE COMPOUND THEREOF

The present invention provides a process for preparing a 2-(3-alkenyl)-1,3-butadiene compound of the following general formula (A), wherein R1 and R2 represent, independently of each other, a hydrogen atom or a linear, branched, or cyclic hydrocarbon group having 1 to 20 carbon atoms and optionally having an unsaturated bond(s), the process comprising the step of subjecting a secondary allylsulfone compound of the following general formula (G), wherein R1 and R2 represent, independently of each other, a hydrogen atom or a linear, branched, or cyclic hydrocarbon group having 1 to 20 carbon atoms and optionally having an unsaturated bond(s), W represents an arenesulfonyl group, and Z represents a halogen atom, to a reductive removal of an arenesulfonyl group, W, at an allyl position, and then subjecting the secondary allylsulfone compound (G) to an elimination reaction of a hydrogen halide, HZ, in this order or in reverse order, to form the 2-(3-alkenyl)-1,3-butadiene compound (A).
Owner:SHIN ETSU CHEMICAL CO LTD

Pyrazolo [5, 1-a] isoindole derivative as well as synthesis method and application thereof

The invention discloses a pyrazolo [5, 1-a] isoindole derivative as well as a synthesis method and application thereof, and belongs to the technical field of organic chemical synthesis. The invention solves the problems of harsh reaction conditions, limited substrate range and the like of continuous multi-step synthesis of a precursor in the existing pyrazolo [5, 1-a] isoindole compound synthesis process. According to the invention, a polarity reversal strategy is adopted, a cyano group is introduced into 1, 5-enyne to change the electronic characteristics of 1, 5-enyne, diazo, olefin and ethynyl benzene are reacted under mild conditions, two rings and three new chemical bonds are constructed through a series of intermolecular [3 + 2] cycloaddition, intramolecular cycloaddition and elimination reactions, and pyrazolo [5, 5-a]-1, 5-a-phenanthrene is efficiently synthesized. According to the present invention, the 1, 1-a] isoindole derivative has characteristics of good synthesis yield, simple operation of the synthesis method, easily available raw materials, good substrate universality and step economy, and provides the effective strategy for the drug design synthesis.
Owner:LIAONING UNIVERSITY OF PETROLEUM AND CHEMICAL TECHNOLOGY

A method for preparing a chiral intermediate of a drug for treating ocular hypertension

The invention discloses a preparation method of a chiral intermediate (S)-3-methyl-1-tert-butoxycarbonyl-1,4-diazepane for treating ocular hypertension, relating to the technical field of pharmaceutical chemicals. The invention comprises the following steps: using 1-benzyl-3-methylpiperidin-4-one as a starting raw material, performing chiral resolution to obtain an intermediate 1, performing an addition-elimination reaction on the intermediate 1 and hydroxylamine hydrochloride to obtain an intermediate 2, performing a Beckmann rearrangement reaction on the intermediate 2 to obtain an intermediate 3, performing an amino deprotection reaction on the intermediate 3 to obtain an intermediate 4, performing an amino protection reaction on the intermediate 4 and di-tert-butyl dicarbonate to obtain an intermediate 5, and performing a decarbonylation reaction on the intermediate 5 to obtain the (S)-3-methyl-1-tert-butoxycarbonyl-1,4-diazepane. The preparation method has the characteristics of readily available raw materials, a simple process and a high product yield, and is suitable for the industrial production of the (S)-3-methyl-1-tert-butoxycarbonyl-1,4-diazepane.
Owner:ANHUI HERYI CHEM