32results about How to "Good reaction selectivity" patented technology

The invention relates to a preparation method of oxilafluorine, which comprises the following steps: by taking a fat alkane compound and a hydroxyethyl reagent as raw materials, carrying out tank closing reaction, then reacting under the action of an alkaline reagent, and finally salifying to obtain the target product oxilafluorine. According to the method, the tank closing reaction is directly carried out, other auxiliaries are not needed, the amino compound serves as a reaction raw material and also serves as an acid-binding agent, use of other organic reagents can be reduced, and the method is more environmentally friendly. Meanwhile, the synthesis method provided by the invention is novel, good in reaction selectivity, simple and convenient in route and high in yield.

The invention relates to a preparation process of high-performance green flame-retardant plywood, which comprises the following steps: synthesis of a cross-linking agent furandicarboxylic acid-NHS active ester (FDCA-NHS), preparation of a high-temperature meal adhesive, preparation of waterborne epoxy resin, preparation of an L-Trp-DOPO inorganic phosphorus-containing flame retardant, preparation of an epoxy resin flame-retardant material, preparation of the high-performance green flame-retardant plywood and the like. The preparation method creatively combines the esterification reaction, the phase inversion method, the chemical one-step method, the hot pressing method and other preparation methods, the prepared high-performance green flame-retardant plywood has the advantages of being good in mechanical property, excellent in flame retardance and the like, has the characteristics of being wide in raw material source, high in renewability, high in reaction activity and the like, conforms to the green and environment-friendly concept and has wide application prospects. The plywood is wide in application field and wide in application prospect.

The invention relates to a method for preparing a methyl propionate palladium complex through free coordination cage effect stabilization ethylene hydrogen esterification, which aims at the problem that central metal of the palladium complex for preparing methyl propionate through ethylene methyl esterification is easy to gather and inactivate, and utilizes the cage effect of a stabilizer to construct a cage network around the palladium complex; meanwhile, the free coordination effect is utilized to cooperate with a bidentate phosphine ligand, so that the formation of palladium black inactivation of an active component palladium is effectively slowed down, the stabilization time is maximally prolonged by 360 hours, the TOF value is as high as 20000 h <-1 >, and the selectivity is 100%. The hydrogen esterification reaction system comprises ethylene, CO, methanol, a stabilizer and a palladium complex catalyst; the palladium complex catalyst comprises palladium acetate, 1, 2-bis (di-tert-butylphosphinomethyl) benzene and an acid accelerant. According to the method, the stability of the palladium complex is greatly improved while high catalytic activity and selectivity of the reaction are guaranteed, the reaction condition is mild, the atom utilization rate is high, and the method has a good application prospect in the reaction for synthesizing methyl propionate through ethylene hydrogen esterification.

The invention relates to a catalyst for preparing anisole through phenol methanol etherification as well as a preparation method and application of the catalyst. The catalyst takes aluminum phosphate as a carrier and is doped with zirconium oxide; on the basis of the mole number of Al, the mole ratio of P to Al is (0.05-2): 1, and the mole ratio of Zr to Al is (0.08-0.20): 1. Dropwise adding the aluminum-zirconium mixed aqueous solution into the phosphorus source aqueous solution, stirring, standing and washing to obtain a solid sample; and drying and roasting the solid sample to obtain the aluminum phosphate catalyst. Under the action of the catalyst, phenol and methanol are catalyzed to generate anisole. Compared with the prior art, the phenol conversion rate is greater than or equal to 50%, the anisole selectivity is greater than or equal to 85%, highly toxic dimethyl sulfate and a large amount of alkali are not needed, the process is green, the cost is low, separation is simple, and the method is suitable for large-scale industrial production of anisole.

The invention discloses a preparation method of 5-(difluoromethoxy) pyrazine-2-amine. The 5-(difluoromethoxy) pyrazine-2-amine is used as a raw material. The preparation method comprises the following specific steps: (1) taking a compound 1 as an initial raw material, and carrying out difluoromethylation reaction to prepare a compound 2; and (2) carrying out Ullmann coupling reaction on the compound 2 to prepare a target product, namely the 5-(difluoromethoxy) pyrazine-2-amine. The preparation method provided by the invention is short in process route, convenient to operate, mild in reaction condition, easy to control, relatively low in cost, suitable for process amplification, easy in product purification and relatively high in yield.

The present invention relates to a method for preparing 3-methylphenethyl ether, the method comprising the following steps: under the action of a catalyst, catalyzing m-methylphenol and ethanol to generate 3-methylphenethyl ether, wherein the catalyst is a silver-tin-zinc composite nitrogen silicon compound. The yield of the present invention is as high as more than 90%, and can be continuously and stably operated for 3000h. The process has high carbon atom utilization rate, adopts a continuous fixed bed process, has high reaction efficiency, does not need to use other solvents, and has low separation cost. And ethanol cost is low, and the overall process cost is greatly reduced. In addition, the reaction steps are simple, synthesis is achieved in one step, has good reactivity and selectivity, can achieve long-term stable operation, and is an ideal process for industrial production.

The invention provides a hydrocracking catalyst, which is characterized in that a catalyst I is formed by mixing a Y molecular sieve, alumina and an adhesive to serve as a carrier and is loaded with nickel and tungsten, a catalyst II is formed by mixing a ZSM-5 molecular sieve, alumina and an adhesive to serve as a carrier and is loaded with cobalt and tungsten, and the catalyst I and the catalyst II are mixed to obtain the hydrocracking catalyst. Cobalt and tungsten are loaded on the ZSM-5 molecular sieve, so that the influence of aromatic hydrocarbon on alkane adsorption reaction is reduced, bond breaking and isomerization reaction of alkane are enhanced, the pour point of the transformer oil is remarkably reduced, and the yield of the transformer oil is increased; nickel and tungsten are loaded on the Y molecular sieve, so that the ring-opening cracking reaction of aromatic hydrocarbon is enhanced, the aromatic hydrocarbon content in the transformer oil can be remarkably reduced, and the stability and chromaticity of the transformer oil are improved. The composite catalyst gives consideration to indexes of the aromatic hydrocarbon content and the pour point of the transformer oil, can realize partitioned reinforcement of an aromatic hydrocarbon ring-opening reaction and a paraffin bond-breaking isomerization reaction, and can directly produce a qualified transformer oil product.

The application discloses a pyridine-yne-benzene-yne diaromatic yne precursor, which is the first aromatic yne precursor capable of continuously generating pyridine-yne-benzene-yne. The diaromatic yne precursor can be compatible with multiple substituted alkyl, aryl, silicon, alkoxy, halogen and other functional groups. The diaromatic yne precursor can have a high-selectivity nucleophilic reaction with oxygen, nitrogen, sulfur and other nucleophilic reagents to quickly construct carbon-heteroatom bonds, and can have a [4+2] cycloaddition reaction with diene to quickly construct double carbon-carbon bonds, so that the diaromatic yne precursor can be used for efficiently and quickly preparing multiple substituted pyridine, benzene ring and other derivatives, and has a wide application prospect.

This invention discloses a phosphonothiolated binaphthol derivative and its synthetic method. Using readily available binaphthioonium salts as starting materials, secondary phosphine oxides as coupling agents, and a base as a promoter, a series of phosphonothiolated binaphthol derivatives are generated. This invention features simple raw material preparation, very mild synthetic reaction conditions, convenient experimental operation, high reaction efficiency, and diverse functional groups.

The invention provides a preparation method of a cyclopentylpyridine derivative. The cyclopentylpyridine derivative is prepared through Hofmann alkylation reaction, ester hydrolysis, rearrangement reaction, reduction reaction and condensation reaction. The route is high in yield, simple in post-treatment and suitable for industrial production.

The application belongs to the field of pharmaceutical chemical industry, and particularly relates to a liquid-phase preparation method of a side chain of somatuline. The preparation method of the application is that Fmoc-His(Trt)-OH reacts with H-Aib-OtBu under the action of a condensing agent T3P to obtain Fmoc-His-Aib-OH. The preparation method provided by the application simplifies operation steps, can control monomer impurities below 0.05%, can control inferior isomer impurities below 0.01%, is short in a synthesis period, is low in cost, has few by-products, and is suitable for industrial production.

The invention discloses a preparation method of irisone, which comprises the following steps of: performing condensation reaction on citral (compound II) serving as a raw material and acetone to obtain pseudoionone (compound III); the preparation method comprises the following steps: carrying out a cyclopropanation reaction with diethyl zinc and diiodomethane under the action of a catalyst to obtain a compound IV, carrying out an intramolecular cyclization reaction on the compound IV under the action of the catalyst, and carrying out post-treatment to obtain a compound I. The route is mild in reaction condition, simple and convenient to operate, stable in process and good in reaction selectivity; the proportion of alpha-irisone in the crude product of the compound I is high, the total yield can reach 78%, and the method is suitable for large-scale industrial production.

Disclosed is a method for producing light aromatic hydrocarbons from C9+ aromatic hydrocarbons, comprising a step of contacting a C9+ aromatic hydrocarbon with a dealkylation catalyst comprising a KL zeolite, and platinum and a modifying metal supported thereon in the presence of hydrogen, to obtain a light aromatic hydrocarbon, wherein the modifying metal is selected from the group consisting of Group IIA metals and rare earth metals. By using a Pt / KL catalyst comprising a specific modifying metal in the dealkylation reaction of C9+ aromatic hydrocarbons for producing light aromatic hydrocarbons, the method shows the advantages of high conversion rate of feedstock, high yield of light aromatic hydrocarbons, good reaction selectivity and the like.

The invention discloses a preparation method and application of a zinc monatomic doped oxygen material, and relates to the technical field of catalytic materials.The preparation method comprises the steps that zinc salt and 2-methylimidazole react in an organic solvent, and a zeolite imidazate framework material is obtained through ultrasonic treatment, self-assembly, centrifugal washing and drying; performing primary pyrolysis on the framework material in an inert atmosphere, and performing acid pickling, washing and drying to obtain a zinc monatomic material; and performing alkali treatment on the zinc monatomic material and an alkaline substance, performing secondary pyrolysis in an inert atmosphere after drying, and performing acid pickling, washing and drying again to obtain the zinc monatomic doped oxygen material. The zinc monatomic doped oxygen material comprises a carbon carrier and zinc monatomic active sites dispersed on the carbon carrier. The material can be used for electrocatalytic preparation of hydrogen peroxide in a two-electron oxygen reduction reaction, and has a good application prospect.

The invention discloses a preparation method of 4 '; the novel preparation process comprises the following steps: under the protection of inert gas, dissolving a chiral ligand and a metal salt in an organic solvent, stirring the mixture for 30 minutes to 1 hour at room temperature, adding a solution of a compound II into a catalyst solution, stirring for 15-30 minutes at a low temperature of-40 DEG C, adding a compound I, an activating agent and an alkali reagent, stirring for 15-30 minutes at a low temperature of-40 DEG C, and reacting for 1-2 hours to obtain a compound I; and continuously stirring at-40 DEG C to react for 6-8 hours, monitoring the proceeding of the reaction by HPLC (High Performance Liquid Chromatography), and separating a product after the reaction is completed to obtain a compound III. The method has the beneficial effects that the operation is simple, the reaction steps can be effectively reduced, the reaction route is short, the raw materials are easy to obtain, the reaction time is short, and the production cost and the labor cost can be effectively reduced; the product yield is high, the reaction selectivity is good, the product purity is high, the reaction product yield is high, the selectivity is good, the target product can be obtained at a high yield, and meanwhile, the post-treatment difficulty of the product is reduced.

The invention belongs to the field of drug synthesis, and specifically relates to a synthesis method of tetrahydrocarbazolone, an intermediate of ondansetron, wherein 2-bromo-2-cyclohexene-1-one and 2-nitrobenzeneboric acid are used as raw materials, tetrakis(triphenylphosphine)palladium is used as a catalyst, a coupling reaction is performed to generate a compound shown in formula III, and then iron powder is used to reduce the compound shown in formula II, and then anhydrous phosphoric acid cyclization reaction is performed to obtain the compound. The method has high conversion rate, saves reaction time, avoids the use of ionic liquid catalysts while ensuring yield, and does not need to increase subsequent three waste treatment steps.

The invention belongs to the technical field of chemical synthesis, and discloses a preparation method of deuterated vitamin A. According to the method, glycolic acid is taken as a raw material, an isotope labeled methyl Grignard reagent is added to synthesize a deuterated intermediate based on a series of reactions such as an HWE reaction, reduction and oxidation, and the deuterated intermediate and BETA-cyclocitral are subjected to a series of reactions to synthesize the deuterated vitamin A, specifically VA-D6. The deuterated vitamin A prepared by the method is relatively high in deuteration rate, and the deuteration rate of the deuterated vitamin A is higher than 99%. The invention provides a synthetic method which is relatively high in deuteration rate, good in reaction selectivity, relatively high in yield, simple and convenient to operate and safe for preparation of deuterated vitamin A.

The application belongs to the technical field of medicine, chemical industry and related chemistry, and discloses a preparation method of difluoromethyl arene compound based on palladium catalytic decarbonylation coupling. The method uses aryl boronic acid as a raw material, uses N, N-disubstituted difluoroacetamide compound as a difluoromethylation reagent, and prepares difluoromethyl arene compound under the catalysis of palladium, so that the green and efficient synthesis is realized. The method has the advantages of easy preparation and storage of the difluoromethylation reagent, high reaction selectivity, good functional group compatibility, wide substrate application range, environmental friendliness and the like. Since the difluoromethyl arene compound is an important functional molecular skeleton structure, the compound has very wide application in the fields of fine chemical industry and pharmacy, so that the application has great application value and social and economic benefits.

The invention discloses a high-conversion-rate process and system for continuously synthesizing bis (diethylamino) silane by a gas phase method, and belongs to the technical field of fine chemical engineering and advanced material preparation. The process takes dichlorosilane and diethylamine as raw materials, and comprises the following steps: carrying out system inerting pretreatment; accurately metering the raw materials according to a specific molar ratio of (1: (4.0-5.0)), gasifying and mixing; the mixed gas is subjected to a continuous gas-phase reaction at 60-70 DEG C (preferably 65 DEG C), and solid byproducts are suspended through enhanced heat transfer and stirring; continuously discharging the reaction slurry through liquid level control, and removing solids through two-stage online filtration (containing nanoscale fine filtration); and finally, continuously rectifying the filtrate under reduced pressure to obtain a high-purity product. According to the method, solvent pollution is thoroughly eliminated, the bottlenecks of easy blockage and difficult continuity of a gas phase method are overcome through precise temperature control and an online solid removal technology, and the conversion rate gt of dichlorosilane is realized; the product purity is gt; 99.9% stable continuous production is achieved, and the high-end semiconductor process requirements are met.

The invention provides a composite hydrocracking catalyst, which is prepared by mixing a ZSM-5 molecular sieve and alumina-loaded nickel and molybdenum as a catalyst I and a Beta molecular sieve and alumina-loaded cobalt and molybdenum as a catalyst II. According to the present invention, the indexes of the aromatic hydrocarbon content and the pour point of the transformer oil can be considered, and the aromatic hydrocarbon ring-opening reaction and the alkane bond-breaking isomerization reaction can be subjected to the partition strengthening so as to reduce the aromatic hydrocarbon content and the pour point in the hydrocracking diesel oil, such that the qualified transformer oil product can be directly produced by using the conventional hydrocracking means.

The present invention relates to a preparation method of triacetaldehyde, using ionic liquid 1-ethyl-3-butylsulfonic acid imidazole p-toluenesulfonate as a catalyst, no other solvent is required during the reaction process, cost is saved, and it is more environmentally friendly. In addition, the method of the present invention not only greatly improves the conversion rate of acetaldehyde, but also has good reaction selectivity, improves the utilization rate of raw materials, and has more atomic economy. Furthermore, the post-processing of the present invention is simple, and the product can be separated by a simple vacuum distillation operation, and the ionic liquid catalyst can be reused, which is more environmentally friendly.

The invention discloses a biosynthesis method of an ezetimibe intermediate, which comprises the following steps of: adding a compound I into a reaction bottle, adding a solvent for dissolving to obtain a solution of the compound I, dissolving carbonyl reductase, coenzyme and coenzyme circulating enzyme into a buffer solution to obtain a buffer solution of enzyme, adding the buffer solution of enzyme into the solution of the compound I, and reacting to obtain the ezetimibe intermediate. And carrying out heat preservation reaction until the reaction is finished, and separating a product to obtain a compound II, namely the ezetimibe intermediate compound ZT-5. The method has the beneficial effects that the biosynthesis method adopted by the invention effectively solves the problems that in the prior art, a large amount of chemical catalyst is used for the ezetimibe intermediate, the synthesis process is complex and the like; by adopting the biosynthesis method, the use of chemical catalysts can be reduced, so that the production cost is reduced, the pollution caused by chemical reagents is reduced, the reaction selectivity is good, the product yield is high, the product purity is high, the raw materials are cheap and easy to obtain, and the method is suitable for large-scale production.

The invention provides a modified ZSM-5 molecular sieve and a preparation method thereof. The preparation method comprises the following steps: step 1, forming gel from a silicon source, an alkali source, a metal salt solution and cardanol polyoxyethylene ether sulfonate; and step 2, adding a ZSM-5 seed crystal into the gel, and then crystallizing, drying and roasting to obtain the modified ZSM-5 molecular sieve. The molecular sieve prepared by the method does not use a template agent, the synthesis method is simple, the crystallinity is high, and when the molecular sieve is used for catalytic cracking / cracking reaction, the yield of low-carbon olefins in a target product can be improved.

The invention discloses a novel method for preparing nicosulfuron, which comprises the following steps: taking pyrilamine and phenyl ester as substrates, sequentially adding a solvent and a small molecular auxiliary agent, stirring and reacting in the solvent at 0-100 DEG C for 10 minutes, desolventizing and separating to obtain nicosulfuron wet powder, and drying to obtain a finished product. According to the preparation method disclosed by the invention, the problem of long six-step condensation time of traditional nicosulfuron is solved by optimizing the whole flow of a key preparation process and parameter conditions (including the ratio and the adding sequence of reaction raw materials, a catalyst, reaction temperature and time and the like) of a synthesis process and particularly innovatively adding a small-molecule auxiliary agent; and the productivity and the equipment utilization rate are improved.

The present application relates to a kind of 2-chloro-4-fluoro-5-nitrobenzoic acid synthesis method, belong to the technical field of organic chemistry.The synthesis method uses 2-chloro-4-fluorobenzoic acid as raw material, and reacts with concentrated nitric acid acetic anhydride solution;After reaction, the reaction liquid is divided, and the organic phase is concentrated to obtain 2-chloro-4-fluoro-5-nitrobenzoic acid.The acid anhydride is used as reaction solvent in the present application, compared with the concentrated sulfuric acid solvent system used in prior art, not only greatly reduces the consumption of acid raw materials, but also because of the mild reaction environment of acid anhydride solvent system, the reaction selectivity is excellent, the reaction conversion can be accurately oriented, the amount of isomer in product is significantly reduced, the impurities are effectively reduced, and the purity and synthesis yield of target product are greatly improved.

The invention provides a polyene rigid spiro compound as well as a preparation method and application thereof. The preparation method comprises the following steps: dispersing an androstenedione dipolymer in ethanol, firstly adding sodium borohydride to carry out a regioselective reduction reaction, then adding water to carry out quenching after the reaction is finished, then adding diluted hydrochloric acid to carry out an elimination reaction, and finally carrying out concentration, extraction and organic phase merging, and concentration and purification again to obtain the polyene rigid spiro compound. A novel conjugated diene structure is successfully introduced by carrying out selective reduction and acid-promoted specific elimination on specific keto-carbonyl groups of the conjugated diene, and the conjugated diene shows remarkable proliferation inhibition activity on colorectal cancer, cervical cancer, liver cancer and breast cancer cell strains.

The invention belongs to the technical field of chemical synthesis, and discloses a preparation method of vitamin A. According to the method, BETA-cyclocitral and a prepared intermediate phosphate ester are taken as key raw materials, and based on a Horner-Wadsworth-Emmons reaction, the vitamin A is synthesized through a series of reactions such as reduction, oxidation and the like. The invention provides a synthesis method which is good in reaction selectivity, relatively good in reproducibility, relatively high in yield, simple and convenient to operate and safe for vitamin A preparation.

The invention belongs to the technical field of chemical synthesis, and particularly relates to a preparation method, a detection method and application of a maxacalcitol 24-hydroxyl isomer impurity. The impurity is a maxacalcitol impurity C. The preparation method comprises the following steps: by taking (5E, 7E)-(1S, 3R, 20S)-1, 3-bis (tert-butyldimethylsiloxy)-9, 10-open-loop pregna-5, 7, 10 (19)-triene-20-ol (a compound shown as a formula 1) as a raw material, carrying out three-step chemical reaction of condensation, TBS protection removal and illumination overturning, and carrying out two-step purification of DAC preparation and column chromatography to obtain the maxacalcitol impurity C. The invention further discloses a preparation method of the maxacalcitol impurity C. The preparation method comprises the following steps: preparing the maxacalcitol impurity C. The preparation method is simple in process, low in equipment requirement and good in reaction selectivity, and has instructive significance on quality control of maxacalcitol bulk drugs.

The invention aims to solve the technical problems of low yield, complex operation, cumbersome purification and the like of the upatinib intermediate in the prior art, and provides a synthesis method of the upatinib intermediate. The method comprises a step of carrying out a reaction on a compound A1 and a compound A2 in the presence of an alkaline substance, and compared with a method in the prior art, the method for synthesizing the upatinib intermediate provided by the invention has the advantages that the cost is remarkably reduced and the quality of a final product can be improved on the premise of ensuring the yield.

The present invention relates to a CO 2 A catalytic conversion catalyst and a preparation method and application thereof. The preparation method of the catalyst comprises the following steps: firstly weighing a silicon source, an aluminum source and an inorganic acid aqueous solution to form a white sol, then centrifuging, washing and drying to obtain a white silicon-aluminum composite oxide powder, then adding a binder, rolling and forming a ball to obtain a silicon-aluminum composite oxide carrier precursor; then weighing a first active component precursor, a second active component precursor and an auxiliary component precursor, and loading them on the silicon-aluminum composite oxide carrier precursor by impregnation, drying and calcining to obtain a CO 2 Catalytic conversion catalyst. Compared with the prior art, the catalyst of the present invention has a 2 It has the advantages of high activity, high selectivity and high stability in the reverse water-gas shift reaction.