14 results about "Diethyl oxalate" patented technology

This invention provides an amino-modified copper-silicon catalyst, its preparation method, and its application, belonging to the field of catalyst technology. The copper oxide particles in the copper-silicon catalyst provided by this invention have a small particle size and high dispersibility on the silica surface, which can significantly improve the catalytic activity of the copper-silicon catalyst, thereby improving the selectivity of ethanol in the hydrogenation of diethyl oxalate. Example results show that, at 180℃ and a hydrogen-to-ester ratio of 25, the copper-silicon catalyst provided by this invention achieves a diethyl oxalate conversion rate of 96.66% and an ethanol selectivity of 84.72% for diethyl oxalate. Furthermore, after 270 hours of stable reaction, the diethyl oxalate conversion rate still reaches 94.7%, and the ethanol selectivity still reaches 66.29%, indicating that the copper-silicon catalyst does not show significant deactivation.

The application discloses a method for preparing N-ethoxyl oxalyl alanine ester by using a dynamic tubular reactor, which comprises the following steps: (1) reacting L-alanine, diethyl oxalate and 4-dimethylaminopyridine in the dynamic tubular reactor; (2) removing light components from the reaction solution; (3) reacting the reaction solution after removing the light components and ethanol in the dynamic tubular reactor; and (4) obtaining N-ethoxyl oxalyl alanine ester after removing the light components. Compared with traditional kettle reactors and tubular reactors, the method adopts the dynamic tubular reactor to prepare N-ethoxyl oxalyl alanine ester, and through the regulation of reaction parameters, the selectivity of key by-products N-oxamide and double N-oxamide can be effectively controlled below 2%. The process has the advantages of high reaction yield, high degree of continuous operation, significantly shortened reaction time and no use of high-toxicity materials such as benzene.

The invention discloses a synthesis method of a bithiophene polymer containing a methylthio group and application of the bithiophene polymer containing the methylthio group in a photoelectric device, and the synthesis method comprises the following steps: S1, mixing a monomer A (x mmol) containing thiophene, a monomer B (y mmol) containing the methylthio group and thiophene and a ligand in a nitrogen atmosphere, and then adding iron triacetylacetonate (0.067 M) dissolved in THF to obtain a solution; s2, slowly dropwise adding a toluene solution (1.6 M) of trimethylaluminum into the solution, and finally adding an oxidizing agent diethyl oxalate to obtain a mixed solution; s3, heating and stirring the mixed solution at 70 DEG C, dropwise adding methanol into the reaction solution after 22 hours to stop the reaction, and finally, repeatedly cleaning the reaction solution with various solvents to obtain a solid, namely the polytriarylamine bithiophene polymer containing the methylthio group, the invention relates to the technical field of bithiophene polymer synthesis, and due to the strong combination effect of the methylthio group and a metal interface, the polytriarylamine bithiophene polymer containing the methylthio group can be used for preparing the polytriarylamine bithiophene polymer containing the methylthio group. The polymer introduced with the methylthio substituent shows an excellent passivation effect, so that the energy conversion efficiency and the device stability are greatly improved.

The application provides a production process of a vitamin B6 intermediate N-ethoxyoxalyl-L-alanine ethyl ester and belongs to the technical field of compound synthesis. Alanine 1 and oxalic acid diethyl ester 2 are stirred under heating at 110 DEG C for 15-20 hours, and the reaction solution is completely dissolved. 80% of product 4 is generated, and 20% of intermediate product 3 is generated. The intermediate product 3 is subjected to hydroxyl esterification by adding a catalyst (concentrated phosphoric acid) and anhydrous ethanol to generate the product 4. The route generates most of the product through acylation reaction, and a small amount of intermediate is subjected to esterification reaction to generate the product. The application has the advantages of short reaction time, high production efficiency and the like, and does not need harmful benzene as a solvent.

The invention discloses a wear-resistant liquid crystal polyarylate fiber and a preparation method thereof, and the method comprises the following steps: S1, dopamine deposition polymerization: sequentially dissolving dopamine hydrochloride and hydrogen peroxide in a Tris buffer solution to obtain a mixed solution, rapidly immersing a liquid crystal polyarylate fiber in the mixed solution, and oscillating at the ambient temperature of 25 DEG C for 10-60 minutes to obtain a deposited fiber; s2, chain extension / cross-linking: wiping the deposited fibers, immersing the deposited fibers in a diethyl oxalate solution, and oscillating at 25 DEG C for 5-30 minutes to obtain the wear-resistant liquid crystal polyarylate fibers. According to the wear-resistant liquid crystal polyarylester fiber and the preparation method thereof provided by the invention, the dopamine is subjected to chain extension and cross-linking through the oxalate according to the characteristic that the amino can be quickly condensed with the oxalate, so that a thin layer of firm and smooth coating is formed on the liquid crystal polyarylester fiber, and the wear resistance of the liquid crystal polyarylester fiber is effectively improved.

The utility model discloses a diethyl oxalate feeding and mixing device, and belongs to the technical field of chemical raw material preparation. The diethyl oxalate feeding and mixing device comprises a mixing tank which is fixedly connected with a feeding pipe, and further comprises a connecting pipe which is fixedly connected with the feeding pipe; the mixing part is fixedly connected to the connecting pipe; the first conveying pipe is fixedly connected to the bottom of the mixing part; the second conveying pipe is fixedly connected to the first conveying pipe; the driving rod is rotationally connected to the mixing tank; the stirring blade is fixedly connected to the driving rod; two materials are premixed through the mixing part in the device before mixing, the mixing effect of follow-up mixing can be effectively improved, meanwhile, the materials in the tank are continuously extracted through the driving cylinder arranged in the device, the extracted materials are sprayed out to disturb the raw materials in the tank, the raw materials in the tank can be effectively turned over, and the mixing effect of the raw materials in the tank is effectively improved. Furthermore, the mixing effect of the raw materials is effectively improved.

This invention belongs to the fields of medicinal chemistry and organic synthesis, specifically relating to a stable 3-aminocyclobutane-1,1-dicarboxylic acid diethyl oxalate and its application in the preparation of 3-(cholate-valerate)cyclobutane-1,1-dicarboxylic acid. This invention effectively solves the technical bottlenecks of poor stability, difficulty in purification, and storage by converting unstable free 3-aminocyclobutane-1,1-dicarboxylic acid diethyl oxalate into a specific organic acid salt form. More importantly, this invention discovers that this organic acid salt can be directly used as a reaction intermediate, and can be used efficiently in subsequent amide condensation reactions with cholic acid or its active derivatives without the separation of free amines. This method significantly improves the purity and yield of the key intermediate and its downstream product 3-(cholate-valerate)cyclobutane-1,1-dicarboxylic acid. The process is stable and simple to operate, providing a stable, controllable, and economical preparation route for the industrial production of 3-(cholate-valerate)cyclobutane-1,1-dicarboxylic acid, a key active pharmaceutical ingredient in the liver cancer prodrug LLC-202.

The application relates to the technical field of medicines, and particularly discloses 13C2-alpha-ketoisocaproic acid and a sodium salt thereof, which is prepared by adopting oxalyl dichloride-13C2 as an isotope-labeled raw material, and through three core reactions of low-temperature nucleophilic addition, room-temperature hydrolysis into a salt and acidification refining, and combining with a recrystallization and reduced-pressure distillation purification process to obtain high-purity 13C2-alpha-ketoisocaproic acid sodium salt and 13C2-alpha-ketoisocaproic acid. The synthesis route is short, the reaction condition is mild and controllable, general industrial raw materials are adopted, and large-scale industrial production can be realized; meanwhile, the 13C2 labeling site is introduced, the isotope atom utilization rate is high, the isotope synthesis cost is effectively reduced, high-purity and high-yield products are finally prepared, the batch stability is excellent, the high-end reagent use demand of clinical 13C breath test for evaluating liver mitochondrial function can be completely met, and the application has a wide application prospect.

The invention discloses bi-component foaming printing water-based ink-jet ink, a foaming printing process and fabric, the ink comprises ink 1 and ink 2, an alkaline foaming agent in the ink 1 reacts with an acid-releasing agent in the ink 2, and foaming printing is realized after generated gas overflows. The food-grade sodium bicarbonate in the ink 1 and the diethyl oxalate in the ink 2 are matched for reaction, after carbon dioxide gas is generated and overflows, foaming printing is achieved, the product is non-toxic and harmless, and the problems of toxicity and pollution of a traditional foaming agent are thoroughly solved. The foaming printing process is rapid and uniform in chemical reaction at high temperature, strong in foaming stereoscopic impression, controllable in height and fine and uniform in foam hole, is applied to environment-friendly digital foaming printing, has the characteristics of environment friendliness, high efficiency and high quality, and has huge market application prospect and industrial popularization value.

This invention belongs to the fields of chemical material synthesis and biomedicine, and provides a method for synthesizing α-ketovaline calcium. This method uses environmentally friendly and low-cost diethyl oxalate as a raw material. The pKa value is precisely controlled through a mixed alkali system to suppress the self-condensation side reaction of isobutyraldehyde. After the condensation reaction at 55-60℃, formic acid is generated through alkaline degradation. Byproducts are completely removed using a 1:1 redox reaction of 30% hydrogen peroxide and formic acid, replacing the traditional high-energy-consuming distillation process. The product yield reaches 78.1%, and the purity is ≥99.8%, demonstrating significant advantages in terms of economy, environmental friendliness, and industrial feasibility.

The application discloses a method for synthesizing an efficient catalyst for alkyl oxalate, and relates to a method for synthesizing a catalyst, which comprises the following steps: firstly, raw materials dimethyl oxalate and ethanol are subjected to an ester exchange reaction in a fixed bed or a slurry bed pre-reactor; liquid mixture generated in the pre-reactor is further subjected to reaction and separation in a reaction rectifying tower to separate by-product methanol; material in the reaction rectifying tower is subjected to pressure reduction in a catalyst recovery tower to separate excessive ethanol and triethylamine catalyst, and the catalyst is returned to the pre-reactor after dehydration; material in the catalyst recovery tower is subjected to pressure reduction in a product rectifying tower to separate product methyl ethyl oxalate and diethyl oxalate. The purity of the methyl ethyl oxalate and diethyl oxalate products produced by the process method is close to 99.99% or above, and the purity of the by-product methanol reaches 99.9% or above. The weak alkaline triethylamine catalyst has high catalytic efficiency, is easy to recover, has good stability, has a simple process route, has low requirements on the material selection of equipment and pipelines, has low energy consumption, and has good economic benefits.

The application relates to the technical field of organic synthesis, and particularly discloses a high-efficiency synthesis method of indole-2-carboxylic acid, which comprises the following steps: preparing a high-activity catalyst; preparing a solution containing ethyl nitrophenyl pyruvate by taking o-nitrotoluene and diethyl oxalate as starting materials; adding the solution containing ethyl nitrophenyl pyruvate into a high-pressure kettle, adding the high-activity catalyst, replacing air in the high-pressure kettle with nitrogen, then performing a catalytic hydrogenation reaction, cooling to room temperature after the reaction is completed, filtering the reaction liquid after pressure relief, removing the solvent from the filtrate, and recrystallizing the solid with ethanol to obtain indole-2-carboxylic acid. The application takes o-nitrotoluene and diethyl oxalate as starting materials, synthesizes the target product through two-step reactions, the above conditions are mild and low in cost, the catalyst used in the reaction process is high in catalytic activity, good in cycle stability and easy to recycle.

The application discloses a synthesis method of indole-2-carboxylic acid, which is suitable for industrial production and comprises the following steps: (1) condensation: mixing o-nitrotoluene, diethyl oxalate and sodium ethoxide ethanol solution, raising to 75-85 DEG C and reacting for 1.5-3 hours, adding into water, stirring for 0.5-1.5 hours, removing ethanol, decoloring, filtering, adjusting the pH of the filtrate to 1-2, and obtaining an intermediate; (2) reduction: adding methanol to the intermediate, adding Raney nickel, raising to 55-65 DEG C, adding hydrogen and reacting, lowering to room temperature, filtering, removing methanol, lowering to 0-5 DEG C and preserving for 1-2 hours, and filtering to obtain a crude product; and (3) purification: adding water to the crude product, adjusting the pH to 8-9, decoloring, filtering, adjusting the pH to 2-3, precipitating a solid, filtering, and drying the filter cake.

This invention relates to the field of organic synthesis, and particularly to a method for synthesizing ethyl 2,4-dioxohexanoate. The steps are as follows: a mixture of diethyl oxalate and butanone is added dropwise to an organic solvent containing an alkali at 0-10°C; after the addition is complete, the temperature is raised to 35-45°C, and the reaction is carried out under essentially static or weakly stirred conditions for 6-16 hours; post-treatment yields the target product. This method, through the synergistic effect of "low-temperature dropwise addition" and "high-temperature static reaction," unexpectedly achieves effective suppression of regiomeric impurities, with the isomer content in the product being less than 0.5%. Simultaneously, since the purity of the crude product already meets the requirements of downstream reactions, the traditionally necessary vacuum distillation step can be omitted. This invention offers high yield, process safety, simple operation, and good reproducibility, possessing significant industrial application value.