676 results about "Coupling reaction" patented technology

The invention discloses a method for simulating reaction migration of metal in a xanthate-loaded porous medium. On the basis of a coupling reaction mechanism of metal and an organic complexing agent (xanthogenate) in a porous medium, a multi-surface morphology complexing model (MSM) containing soil native components and xanthogenate is constructed and is combined with a reactive migration numerical model (a coupling water flow and solute migration equation); according to the method, through model calibration and experimental verification, the dynamic migration process of each metal component and the competitive retention distribution of the metal component on different solid-phase components can be accurately simulated and quantitatively analyzed under the complex condition that metal and xanthate coexist.

The invention provides a preparation method of a Joule heat-assisted super-wetting metal net, a metal net with super-hydrophilic performance and a metal net with super-hydrophobic performance. According to the material, carbon nanotubes are firmly adhered to the surface of a metal net through polydopamine mediation to construct a micro-nano coarse structure, a hydrophobic alkyl compound is grafted through a sulfenyl three-component coupling reaction to reduce surface energy, and a super-hydrophilic / underwater super-oleophobic metal net and a super-hydrophobic metal net are prepared respectively. The Joule heating effect of the material is remarkably enhanced by introducing the carbon nanotubes, so that the temperature of the material can be rapidly increased to 100 DEG C or above within 20 seconds under the ultralow voltage of 2.0 V. The characteristic can be effectively used for in-situ heating viscosity reduction of high-viscosity crude oil, continuous and efficient oil-water separation is achieved in a double-channel separation device, the crude oil flux reaches up to about 3985 L.m <-2 >. H <-1 >, and the separation efficiency exceeds 98.6%. The method is also suitable for stainless steel meshes with micron-sized apertures, and can realize efficient separation of various crude oil emulsions.

The invention discloses a method for preparing high-value chemicals through photocatalytic driving of beta-O-4 lignin depolymerization and coupling cascade reaction, and belongs to the technical field of photocatalytic biomass resource conversion. The method comprises the following steps: (1) dispersing a beta-O-4 lignin raw material into a solvent containing a photocatalyst; (2) introducing a normal-temperature chemically stable gas to replace air in a reaction system; and (3) carrying out a depolymerization reaction of beta-O-4 bonds and an in-situ C-C bond coupling reaction under an illumination condition to generate a target product. And (4) separating and purifying the product and recovering the catalyst. Through photocatalytic cascade reaction design, the defects of harsh reaction conditions and multi-step separation in a traditional method are avoided, the method has the advantages of mild reaction conditions, high atom utilization rate, high product selectivity and environmental friendliness, and a new way is provided for high-value utilization of lignin.

The invention discloses an oligonucleotide synthesis process of a sulfo-PMO structure. In the oligonucleotide synthesis process of the sulfo-PMO structure, the molecular structural formula of sulfo-PMO is shown in the specification. According to the invention, the molecular structure of thio-PMO is specifically limited, and the synthesis of nucleotide phosphate amide and (thio) phosphoric acid amide in the solid-phase synthesis oligonucleotide is carried out along the direction from 5'to 3 ', that is, in each cycle period, the O5'or O6' position of the nucleotide phosphate amide and (thio) phosphoric acid amide monomer is firstly subjected to coupling reaction, and then the protecting group is removed at the O3 'or N3' position, so that the oligonucleotide phosphate amide and (thio) phosphoric acid amide are obtained. And releasing active hydroxyl or amino / amido to enter the next cycle. The protecting group adopted by the sulfo-PMO molecule is consistent with the protecting groups of other nucleotides, so that the conversion rate of each step of coupling reaction can be conveniently detected on line.

The invention discloses a 96-hole preassembled plate fat-soluble vitamin pretreatment kit, and belongs to the technical field of in-vitro diagnostic reagents. Comprising magnetic bead suspension liquid, equilibrium liquid, leacheate 1, leacheate 2 and eluent which are carried on a preassembled plate, and the magnetic bead suspension liquid comprises absolute ethyl alcohol and magnetic beads; the preparation process of the magnetic beads comprises the following steps: activating carboxyl of the carboxyl magnetic beads through EDC and NHS; then nitrochlorobenzene and triethylamine are added for a coupling reaction; mixing the coupling reaction product with pyrrolidone, ammonium persulfate and a pore-foaming agent to obtain target magnetic beads; the magnetic beads can be specifically combined with fat-soluble vitamins in human serum or plasma, efficient separation and release of an object to be detected are achieved through a magnetic separation technology, and the magnetic beads are suitable for follow-up mass spectrum quantitative analysis. The kit disclosed by the invention has the characteristics of simplicity and convenience in operation, high extraction efficiency and good stability, the pretreatment time can be remarkably shortened, the detection accuracy is improved, and an efficient solution is provided for clinical detection of fat-soluble vitamins.

The invention belongs to the technical field of material science, and relates to a preparation method and application of an unsaturated bond extended tetraphenyl ethylene siloxane compound. An unsaturated bond is introduced into a siloxane group, and the siloxane group containing the unsaturated bond and a tetraphenyl ethylene derivative are subjected to a coupling reaction. The coupling reaction is carried out in an inert atmosphere, the temperature is 90-150 DEG C, and the time is 6-24 hours. And purifying the product by silica gel column chromatography to obtain the target compound. Unsaturated bonds are introduced into a tetraphenyl ethylene structure, so that the adjustability of the photochromic wavelength is realized, the performance of the compound is remarkably improved, the application range of the compound is remarkably widened, and a new thought and a new method are provided for development of photochromic materials.

The application discloses a kind of high level dipole orientation tetraphenyl benzene derivatives and its preparation method and application, the tetraphenyl benzene derivative has structure shown in formula (I):In formula (I), any two of R1, R2, R3, R4 Four groups are each independently selected from N-containing electron-donating group, and the other two are each independently selected from electron-withdrawing group.The tetraphenyl benzene derivative is prepared using two-step suzuki coupling reaction.The tetraphenyl benzene derivative of the application has excellent solid-state light emitting efficiency and high molecular level dipole orientation, and can be used as non-doped light-emitting layer to prepare non-doped blue light organic electroluminescent device with high efficiency, low degree of efficiency roll-off, low start voltage, with maximum external quantum efficiency reaching 8.32%, which is greatly improved compared with prior art, and has wide application prospect in the field of organic optoelectronics.

The invention provides a hydrogen sensor as well as a preparation method and application thereof, and particularly relates to the technical field of sensors. The hydrogen sensor comprises a ceramic substrate electrode and a gas-sensitive layer, the gas-sensitive layer is arranged on the surface of the ceramic substrate electrode, the gas-sensitive layer comprises a composite material formed by doping a semiconductor material with precious metal, the surface of the composite material is coated with a hydrophobic membrane, and the surface of the hydrophobic membrane is coated with a metal layer. The hydrophobic membrane is formed by chemical coupling reaction of hydrophobic silane and hydroxyl groups. According to the hydrogen sensor, by adopting the specific semiconductor sensing material and the hydrophobic membrane, the adaptability and the stability of the hydrogen sensor in a high-temperature alkali liquor corrosion environment are greatly improved, the hydrogen sensor can reliably work for a long time in a severe environment, the replacement frequency of the sensor is reduced, and the use cost is reduced.

The invention belongs to the technical field of chemical synthesis, and particularly relates to a preparation method of 4, 4 '-[oxygen bis (methylene)] bis [5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl)-1H-pyrazole]. The invention provides a preparation method of 4, 4 '-(oxybis (methylene)) bis (5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl)-1H-pyrazole, which comprises the following steps: dissolving a compound shown in a formula IV and a compound shown in a formula V in a solvent, adding alkali, carrying out coupling reaction to obtain a reaction solution, and carrying out post-treatment to obtain a compound shown in a formula VI, namely 4, 4'-(oxybis (methylene)) bis (5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl)-1H-pyrazole. The compound is 4, 4 '-(oxybis (methylene)) bis (5-(difluoromethoxy)-1-methyl-3-(trifluoromethyl)-1H-pyrazole). The preparation method disclosed by the invention is simple and easy to implement, mild in condition, high in safety, suitable for preparing reference substances in laboratories, and beneficial to product quality control and production process development.

The invention discloses a system and a method for preparing adiponitrile by electrolyzing acrylonitrile, and relates to the technical field of chemical product preparation, reaction and separation are efficiently coupled through process innovation, so that an acrylonitrile recovery unit is omitted, the safety is improved, and a modularized external reaction area capable of being flexibly expanded is introduced into the design of a reactor. The design aims to fundamentally break through the physical limitation of traditional equipment on the electrode area, and a brand new technical path is provided for realizing high-efficiency and low-energy-consumption large-scale industrial production. Nearly complete conversion of acrylonitrile is realized through the rectifying tower, and a tower kettle product does not contain unreacted acrylonitrile, so that a complicated acrylonitrile recovery tower and a circulating system do not need to be arranged in a subsequent separation system, the process is remarkably shortened, and equipment investment and operation energy consumption are reduced.

The invention discloses an ordered ion channel polyamide nano composite membrane, a preparation method and application, relates to the field of lithium magnesium membrane separation, and aims to solve the problem of poor selectivity in the prior art. The technical scheme is as follows: amino benzo crown ether is covalently grafted on an ultrafiltration base membrane in situ through diazotization-coupling reaction; then, a polyamide compact layer is prepared on the crown ether nano layer subjected to in-situ self-assembly through interfacial polymerization, and the polyamide nano composite membrane with the ordered ion transmission channel is jointly constructed. The residual amino groups on the surface of the in-situ covalent grafted crown ether nano layer can also participate in interfacial polymerization reaction, so that the ordered ion channel crown ether macromolecular layer and the polyamide compact layer are connected through chemical bonds to jointly form the polyamide nano composite membrane with the ordered ion transmission channel. And the method is suitable for extracting lithium from the salt lake brine.

The application discloses a 5-position linked naphthalene diisocyanate, a halogenated naphthylamine or a phenolic hydroxyl naphthylamine, which is subjected to an acylation reaction, then subjected to an Ullmann coupling reaction in the presence of a ligand and an inorganic base and under the protection of an inert gas by using a metal or a salt thereof as a catalyst, subjected to amide hydrolysis, and then subjected to a carbonacylation reaction with a carbonacylation reagent to obtain the 5-position linked naphthalene diisocyanate. The application further provides a synthesis method of the 5-position linked naphthalene diisocyanate. The application further provides an application of the 5-position linked naphthalene diisocyanate in preparation of urethane rubber and elastomer, urethane fiber, cast urethane rubber, urethane emulsion and paint, urethane adhesive, shock-absorbing foam material, energy-absorbing foam material and damping foam material. The polylinked naphthalene urethane prepared by using the 5-position linked naphthalene diisocyanate has high cohesive energy and impact modulus, and can be widely applied to high dynamic load and heat-resistant occasions.

The invention discloses an acceptor material containing a part of fluorinated side chain aza fused ring as well as a preparation method and application of the acceptor material. The structural general formula of the acceptor material containing the part of fluorinated side chain aza fused ring is as shown in formula I, wherein R1 and R2 are selected from C1-C30 part of fluorinated alkyl; and EG1 and EG2 are any one of cyano indanone compounds. The preparation method comprises the following steps: carrying out Schpeller coupling reaction on a compound 1 and a compound 2 to obtain a coupling compound 3; the compound 3 and alkylamine R2NH2 are subjected to a Buchwald-Hartwig ring closing reaction, and a fused ring compound 4 is obtained; the compound 4 is subjected to a vilchmidt-hauck hydroformylation reaction to obtain a compound 5; the compound 5 and a terminal group EG are subjected to a Knoevenagel condensation reaction to obtain a final acceptor material. The acceptor material with the near-infrared absorption function is prepared, the spectrum capture range of an organic solar cell is widened, and the performance of a laminated device and a semitransparent device can be improved. Formula I.

The present invention relates to novel compounds of formula (I), optionally conjugated to peptide or protein molecules, and the synthesis thereof. The invention also relates to the use of the novel compounds for coupling reactions with linkers and other molecules. The invention also relates to the use of the novel compounds in bio-orthogonal strain promoted cycloaddition (copper-free), i.e. Click reaction. (I).

The invention relates to a method for synthesizing an iodo-pyridine compound from N-propargyl enaminone, which comprises the following steps: by taking N-propargyl enaminone as a raw material, DMF (Dimethyl Formamide) as a reaction solvent and copper acetate and N-iodosuccinimide as accelerators, carrying out intramolecular coupling reaction at 60 DEG C to synthesize the iodo-pyridine compound. The method for directly synthesizing the pyridine heterocyclic compound through the intramolecular coupling reaction of the N-propargyl enaminone under the non-alkaline condition is disclosed for the first time, reaction substrates are not limited to benzene rings on alkynyl, the application range of the reaction is greatly expanded, and the method has the advantages of being wide in substrate range, strong in functional group application range, mild in reaction condition, easy to operate, safe, high in yield and the like. And raw materials are cheap.

The invention discloses a hydrolysate deacidification-dehydration coupling process and a byproduct recovery method, and belongs to the technical field of hydrolysate treatment. The method comprises the following steps: pretreating a hydrolysate raw material through two-stage filtration; adding the pretreated hydrolysate, a deacidification agent and a dehydration auxiliary agent into a coupling reaction device, and synchronously carrying out deacidification-dehydration reaction under the conditions of 60-120 DEG C and 0.1-0.5 MPa; after the reaction, separating to obtain a deacidification and dehydration product and a mixed solid phase; and dissolving and crystallizing the mixed solid phase to recover high-purity byproducts. The deacidification and dehydration synergistic interaction is achieved, the acidity reduction rate is larger than or equal to 85%, the water content is smaller than or equal to 5%, and the process time consumption is shortened by 28.6%; the byproduct purity is not less than 90%, and the recovery rate is not less than 80 A tail gas treatment system is additionally arranged to ensure that environmental protection reaches the standard. The process is suitable for biomass, polysaccharide and protein hydrolysate treatment, has the advantages of high efficiency, good resource utilization rate and the like, and provides an efficient solution for hydrolysate industrial treatment.

A dichroic bis-azo biphenyl dye of the following formula:The substituents R1, R2, R3, R4 are alkyl (CnH2n+1) or alkenyl (CnH2n−1) groups with n=1-18. At least one substituent among R1R2R3R4 is different from the other substituents. A benzidine-free method of making a dichroic bis-azo biphenyl dye is provided in which the biphenyl portion of the dye is formed from different first and second mono-azo dyes by a cross-coupling reaction, which may be a Suzuki reaction. A polarizer is formed from a photoaligned layer of the bis-azo biphenyl dye on a substrate and exhibits a dichroic ratio of at least 40. Chemical modification of the photoaligned bis-azo biphenyl dye layer creates a broad-band thin film polarizer with low light scattering and high thermal and photo tolerances.

The invention relates to the technical field of biological medicine manufacturing, in particular to an environment-friendly and efficient Difelikefalin preparation method. According to the method, a solid-phase peptide synthesis technology is adopted, and the core is that a green mixed solvent system composed of 2-methyltetrahydrofuran and cyclopentyl methyl ether is used for comprehensively replacing traditional toxic solvents such as DMF and DCM. The method comprises the steps of resin swelling, Fmoc deprotection, amino acid coupling, peptide chain cutting, purification and freeze drying, a piperidine / 2-MeTHF solution is adopted in the deprotection, an optimized HATU / DIPEA activation system is adopted in the coupling reaction, a TFA / 2-MeTHF / water mixed solution is adopted in the cutting, and an ethanol-water chromatographic system is adopted in the purification. According to the invention, closed-loop circulation of the solvent is also realized, and 2-MeTHF and CPME are purified through rotary evaporation and reused in the synthesis process. According to the method, high purity and high yield of the product are guaranteed, production toxicity and environmental hazards are remarkably reduced, and the method has excellent industrial application prospects.

The invention discloses a polyol gradient synergetic depolymerization-esterification coupling reaction device for PETG chemical recovery, and belongs to the technical field of depolymerization-esterification coupling reaction devices, the polyol gradient synergetic depolymerization-esterification coupling reaction device comprises a main reaction kettle, the main reaction kettle is of a vertical cylindrical structure, the top of the main reaction kettle is fixedly connected with a sealing cover, the sealing cover is connected with a plurality of feeding ports, and the feeding ports are communicated with the main reaction kettle. A liquid collecting cavity is connected below the main reaction kettle, a return pipe is connected to the bottom of the liquid collecting cavity, a one-way valve is arranged on the return pipe, a multi-stage alcohol feeding system is arranged on one side of the main reaction kettle, a gradient temperature control jacket assembly is arranged on the other side of the main reaction kettle, and an in-situ esterification module is arranged on the inner side of the main reaction kettle. According to the method, multiple alcohol reagents are introduced according to the gradient synergistic effect, the breaking requirements of different types of ester bonds in PETG molecules are accurately matched, the depolymerization and esterification processes are coupled in situ, efficient, low-consumption and high-valued closed-loop recovery is achieved, and the defects that depolymerization is not thorough, products are complex, the technology is tedious and the like when PETG is treated in the prior art are effectively overcome.

The invention discloses a preparation method of rosmeltirol, and belongs to the technical field of chemical synthesis. The method comprises the following steps: taking a compound I as an initial raw material, generating a compound II through base catalysis, and performing bromination reaction to obtain a compound III; carrying out Suzuki coupling reaction on the compound III and isopropenyl boronic acid pinacol ester to obtain a compound IV; then reacting with 2, 6-dichloro-4-aminophenol to generate a key intermediate V; performing diazotization coupling reaction to obtain a compound VI, and performing ring closing reaction to form a compound VII; and finally, carrying out hydrogenation reduction to obtain the target product rosimeltirol. The conventional catalyst is adopted to replace a noble metal system, industrial easily-available raw materials are selected to avoid the use of a Grignard reagent, the yield of each step is up to 85% through optimization of reaction conditions, and the purity of a final product reaches 99.8% or above; meanwhile, the raw material cost is reduced, the emission of three wastes is reduced, the operation safety is improved, and a reliable technical scheme is provided for large-scale production of the rosmeltirol.

Vertical multi-stage disc countercurrent atmosphere pressure reaction system and reaction method thereof belong to the field of chemical process equipment. In view of the problems of uneven temperature distribution, uncontrollable material residence time and difficulty in realizing continuous operation in the existing equipment, a plurality of large discs and small discs arranged alternately are arranged in the vertical direction inside the cylinder body in sequence, each disc is connected with the central rotating shaft to form an integral rotating structure, a first type of discharging scraper for conveying material from the outer side to the inner side is arranged on the large disc, and a second type of discharging scraper for conveying material from the inner side to the outer side is arranged on the small disc, through the reverse pushing action of the two types of scrapers, the material forms an "outer-inner-outer" alternating migration path between the discs at each stage, thereby constructing a complex flow trajectory coupled with spiral motion and broken line motion in space. The invention realizes the transformation from traditional heat treatment to multi-field coupling reaction control, and has the advantages of high heat transfer efficiency, good reaction uniformity and high degree of continuous operation.

This application relates to a highly acid and alkali resistant pigment, Red 48:1, and its preparation process, belonging to the field of chemical pigment manufacturing technology. The pigment is prepared from 2B acid, sodium nitrite, 2,3 acid, a barium-lanthanum-calcium multimetallic salt component, aminotrimethylenephosphonic acid, zirconium salt, melamine-formaldehyde resin prepolymer, epoxy resin emulsion, silane coupling agent, and surfactant. The preparation process includes sequential diazotization and coupling reactions, followed by a co-lake reaction with the addition of multimetallic salts; then interfacial anchoring via aminotrimethylenephosphonic acid, and inorganic deposition hybridization via droplet addition of zirconium salt; finally, a staged crosslinking coating reaction is performed with the aforementioned resin and coupling agent. This invention constructs an inorganic-organic hybrid coating layer in situ on the pigment core surface of the multimetallic lake, physically blocking the penetration pathways of acid and alkali ions, thus improving the pigment's resistance to acid and alkali bleeding and its resistance to ultraviolet aging.

A method to produce a mixture comprising poacic acid (X) and poacidiene (Y) and the resulting product-by-process. The method includes the steps of subjecting a solution of ferulic acid to a free-radical coupling reaction to yield an intermediate mixture comprising ferulic acid dehydrodimers and decarboxylating the intermediate mixture to yield a product mixture containing poacic acid (X) and poacidiene (Y).

The invention relates to the technical field of preparation of rare earth functional materials, and particularly discloses a preparation method and device of a trinity coupling reinforced rare earth oxide. The preparation device comprises an ultrasonic-microwave composite resonant cavity, a micro-channel reaction unit, an ultrasonic unit, a microwave heating unit, a pulse synchronous triggering module and a multi-parameter linkage closed-loop control module, and in-situ synchronous coupling of a micro-channel, ultrasonic and microwave in the cavity can be achieved. The preparation method is implemented based on the device, sequentially comprises five steps of raw material preparation, parameter presetting, coupling reaction, closed-loop regulation and control and product collection, and can realize time-space synchronous propulsion of precursor nucleation, agglomeration inhibition and in-situ crystallization. According to the device and the preparation method, the mass transfer efficiency in the rare earth oxide preparation process can be effectively improved, product particle aggregation is inhibited, the stability and the production efficiency of continuous production are improved, and the large-scale preparation requirements of high-end rare earth oxides are met.

This invention discloses a migration C(sp²)-H / C(sp³)-H cross-coupling reaction achieved using metal / photoredox catalysis, belonging to the fields of organic chemistry and medicinal chemistry. Under the action of a nickel source, photocatalyst, ligands, base, and additives, this invention enables the reaction of alkanes with ortho-alkenyl-substituted aryl halides or ortho-pyridine-substituted aryl halides in an organic solvent under light irradiation, yielding a series of polysubstituted olefins or polysubstituted aromatic compounds with excellent regioselectivity, stereoselectivity, and good yields, which can serve as active pharmaceutical molecules. This invention uses inexpensive transition metal nickel as a catalyst, readily available alkanes and haloaromatics as raw materials, and features mild and simple conditions, good functional group compatibility, and easy operation.

This application discloses a negative curvature polycyclic aromatic hydrocarbon containing an eight-membered ring, its synthesis method, and its application, belonging to the field of organic synthesis. The synthesis method uses a haloacenaphthene derivative as a starting material. First, a tetrahalogenated key intermediate containing an eight-membered ring is constructed via a titanium tetrachloride-catalyzed cyclization tetramerization reaction. Subsequently, this intermediate undergoes a cyclization coupling reaction with an alkyne compound in the presence of a palladium catalyst, silver salt, and phosphine ligand to generate a negative curvature polycyclic aromatic hydrocarbon containing an eight-membered ring. The synthesis method of this application avoids multi-step precursor synthesis, resulting in a concise process. It allows for the flexible introduction of functional groups such as trifluoromethyl and silyl groups, improving the solubility and processability of the material. The obtained product exhibits a non-planar configuration, a narrow optical band gap, and excellent electron transport properties, making it suitable for applications... n Applications include semiconductors, chiral optoelectronic materials, and nano-carbon materials.

The invention discloses a synthesis method of 2, 4-dichloro-5-cyclopropylpyrimidine, which comprises the following steps: taking compounds 5-bromo-2, 4-dimethoxypyrimidine and cyclopropylboronic acid as raw materials, carrying out Suzuki-Miyaura coupling reaction to obtain an intermediate compound 5-cyclopropyl-2, 4-dimethoxypyrimidine, then taking phenylphosphonic dichloride as a chlorination reagent, and carrying out chlorination reaction to obtain the target compound 2, 4-dichloro-5-cyclopropylpyrimidine. The invention relates to 2, 4-dichloro-5-cyclopropyl pyrimidine. In the key steps, under the condition that phenylphosphonic dichloride is used as a chlorination reagent and a reaction solvent, through high-temperature reflux activation, methoxy as a leaving group is attacked by chlorine nucleophilic, methoxy (-OCH3) on a pyrimidine ring is substituted by a chlorine atom (-Cl), and the target product 2, 4-dichloro-5-cyclopropyl pyrimidine is generated. Finally, the target compound 2, 4-dichloro-5-cyclopropyl pyrimidine is obtained through short steps, simple and convenient operation, mild reaction conditions and ideal yield.

The invention belongs to the field of organic synthesis, and particularly relates to a synthetic method of a diaryl methane compound. A toluene derivative as shown in a formula 1, an aryl iodide as shown in a formula 2 and a styrene derivative as shown in a formula 3 are subjected to a reaction in the presence of a catalytic amount of PdCl2 (dppf) and 4, 6-di (diphenylphosphine) phenazine and an equivalent amount of LiN (SiMe3) 2 and CsF to synthesize the diaryl methane compound as shown in a formula 4. The coupling reaction of the toluene derivative, the aryl iodide and the styrene derivative is realized by adopting a catalytic amount of PdCl2 (dppf), and the palladium catalyst shows obvious catalytic performance.

This invention provides an intermediate impurity of roxadustat and a method for preparing the impurity. The method for preparing roxadustat impurity I includes: dissolving compounds II and III in an organic solvent, and conducting a coupling reaction under a nitrogen atmosphere and a reaction temperature of 40–60°C in the presence of a base to obtain roxadustat impurity I. This preparation method features mild reaction conditions, simple operation, low time cost, high yield, and high product purity. It can efficiently obtain sufficient quantities of high-purity impurity reference standards, playing a positive role in the quality control of roxadustat intermediates and roxadustat active pharmaceutical ingredients, and has good application prospects.

This invention discloses a method for preparing the DPP1 inhibitor bresocarte, belonging to the field of pharmaceutical synthesis. Specifically, the method includes the following steps: N-tert-butoxycarbonyl-L-4-bromophenylalanine reacts with methanesulfonyl chloride or 4-nitrobenzenesulfonyl chloride in the presence of a base, followed by amination substitution to obtain intermediate 1; then, it undergoes dehydration in the presence of trifluoroacetic anhydride to obtain intermediate 2; next, it undergoes a coupling reaction with pinacol diboronate to obtain intermediate 3; then, it undergoes a coupling reaction with bromide compound 4 to obtain intermediate 5; then, it undergoes cyclization with di-tert-butyl dicarbonate in the presence of sodium methoxide to obtain intermediate 6; then, it undergoes deprotection in the presence of hydrogen chloride to obtain intermediate 7; next, it undergoes condensation with compound 8 to obtain intermediate 9; finally, it undergoes deprotection in the presence of hydrogen chloride to obtain the inhibitor bresocarte. This method provides a new synthetic approach, with low overall cost, simple operation, high yield, and suitability for industrial production.