16 results about "Methyl carbamate" patented technology

The invention belongs to the technical field of pharmaceutical analysis, and discloses a method for determining two potential genotoxic impurities in carbon [13C]-urea by gas chromatography. Comprising the following steps: (1) preparing a sample solution; (2) preparing a reference solution; (3) taking nitrogen as carrier gas, and detecting by adopting a medium-polarity or weak-polarity chromatographic column separation system; and (4) calculating by a peak area through an external standard method to obtain the accurate contents of methyl carbamate and ethyl carbamate in the carbon [13C]-urea. The method disclosed by the invention is simple to operate, good in specificity, linearity, precision and accuracy and high in sensitivity, and can realize accurate detection of residual potential genotoxic impurities, namely methyl carbamate and ethyl carbamate, in the carbon [13C]-urea.

The utility model mainly relates to the technical field of tail gas treatment, and provides a methyl carbamate ammonia-containing tail gas treatment device which structurally comprises an operation support, a Roots blower is fixedly arranged at the bottom of the operation support, material grooves are fixedly formed in the front side and the rear side of the right end of the operation support respectively, and transition pipes are fixedly arranged at the bottoms of the material grooves. The bottom of the transition pipe is fixedly connected with a feeding port in the right end of the auger conveyor, methyl carbamate powder in the trough and the transition pipe is conveyed into the collecting barrel through the auger conveyor, the powder is raised and scattered in the collecting barrel, and the powder is conveyed through the auger conveyor and scattered in the collecting barrel. At the moment, the Roots blower is matched with the exhaust pipe, air exhaust treatment is carried out in the collecting barrel through the filter cartridge and the dust filtering cloth bag, and air in the collecting barrel is pumped into the dilute acid spraying kettle to be treated.

This invention discloses a method for preparing albendazole, belonging to the field of pharmaceutical preparation technology. The method includes: (1) cyclization reaction: using methyl cyanocarbamate and 4-(propylthio)phenyl-1,2-diamine or their hydrochloride as raw materials, reacting in water, methanol, ethanol or a mixed solvent in the presence of an acidic catalyst or an alkaline buffer; (2) crystallization and separation of crude product: adjusting the pH of the reaction solution to 3-5, and separating the solid and liquid to obtain the crude product; (3) washing and purification: the crude product is washed successively with toluene, methanol and water, and dried to obtain the purified product; (4) refining and post-treatment: dissolving, decolorizing and recrystallizing with a formic acid-water mixed solvent, drying, pulverizing and sieving, and packaging to obtain the finished product. This invention uses a green and environmentally friendly solvent system, suppresses side reactions through precise pH control, optimizes the three-stage washing and recrystallization process, achieves a molar yield of over 88%, a purity of 99.85%, meets pharmaceutical standards, and is suitable for large-scale production.

Fungicidal compositions comprising strobilurins The present invention relates to fungicidal compositions comprising at least one compound selected from the group consisting of (I-1) methyl N-[[5-[1-(2,6-difluoro-4-isopropyl- phenyl)pyrazol-3-yl]-2-methyl-phenyl]methyl]carbamate, (I-2) methyl N-[[5-[1-(4-cyclopropyl-2,6- difluoro-phenyl)pyrazol-3-yl]-2-methyl-phenyl]methyl]carbamate, (I-3) methyl N-[[5-[1-(4-chloro- 2,6-difluoro-phenyl)pyrazol-3-yl]-2-methyl-phenyl]methyl]carbamate, (I-4) methyl N-[[5-[1-[2,6- difluoro-4-(trifluoromethyl)phenyl]pyrazol-3-yl]-2-methyl-phenyl]methyl]carbamate, and as active component 2) at least one compound selected from the group consisting of (II-1) metarylpicoxamid, (II-2) fluoxytioconazole, (II-3) bifemetstrobin, (II-4) cyclobutrifluram or an N- oxide, or an agriculturally useful salt thereof, wherein the weight ratio of compound I to compound II is from 10:1 to 1:10. The invention also relates to an agrochemical composition comprising the composition and a solvent of solid carrier. Further, the invention relates to a non- therapeutic use of the inventive compositions controlling phytopathogenic harmful fungi.

The manufacturing method of the light-transmitting waterproof glue of the present invention includes: providing raw materials: acrylate, methyl carbamate, crosslinking agent, ultraviolet absorber, antioxidant and plasticizer; mixing the above raw materials evenly in proportion to form a viscous solution; and stirring, adjusting, extruding and roll-pressing the viscous solution to form the light-transmitting waterproof glue. This method is simple and low-cost, and the prepared glue has improved high light transmittance, excellent waterproof performance and strong adhesive force.

This invention relates to a method for the efficient preparation of methyl cyanurate, belonging to the technical field of pharmaceutical intermediate synthesis. The method includes the following steps: mixing 1-hydroxyethyl-3-methylimidazolium acetate with a 28-32% potassium phosphate aqueous solution at a mass ratio of (2.8-3.2):1, followed by allowing the mixture to stand and separate into upper and lower phases; adding a cyanamide aqueous solution to the lower phase; and continuously adding methyl cyanurate to the upper phase; stirring the reaction at 40-50°C for 1.5-2.5 hours; allowing the mixture to stand and separate into upper organic and lower brine phases; diluting the upper organic phase with 1.8-2.2 times its volume of deionized water, precipitating a solid, followed by filtration; collecting the filter cake and filtrate; washing and drying the filter cake to obtain methyl cyanurate. This invention achieves directional distribution of reactants, precise suppression of side reactions, and efficient separation of products by constructing a two-phase aqueous system.

This invention relates to a method for preparing compound (I) or a pharmaceutically acceptable salt or solvate thereof. In particular, such a method comprises the dehydration cyclization of a 1,2-diacylhydrazine intermediate to form the corresponding 1,3,4-oxadiazole, wherein the dehydration cyclizing agent may be N,N-dimethylaminosulfonyl chloride, N-(triethylammonium sulfonyl)carbamate, phosphorus trichloride, or phosphorus pentachloride, resulting in increased product yield and purity compared to known methods. Compound (I) and pharmaceutical compositions thereof can be used as respiratory syncytial virus (RSV) inhibitors.

The invention relates to a method for synthesizing 1, 5-naphthalene dicarbamate under the catalysis of cerium oxide. The method comprises the following steps: adding 1, 5-naphthalene diamine, dimethyl carbonate and a catalyst into a reactor, and carrying out stirring reaction for 5-10 hours in a nitrogen atmosphere at 150-180 DEG C under normal pressure to obtain 1, 5-naphthalene dicarbamate; wherein the catalyst is cerium oxide, and the addition amount of the catalyst is 40-80% of the mass of the 1, 5-naphthalene diamine; the molar ratio of the dimethyl carbonate to the 1, 5-naphthalene diamine is (30-68): 1. The method reduces the cost loss, is environment-friendly, does not generate toxic gas, chlorine-containing waste or catalyst waste liquid, is simple and convenient in operation process, and can recycle the catalyst for multiple times.

The invention belongs to the technical field of organic chemical synthesis, and provides a cyclohexyl isocyanate synthesis process, which comprises: 1, adding cyclohexylamine and a catalyst A into a solvent, controlling the temperature at 0-5 DEG C, slowly dropwise adding dimethyl carbonate, maintaining the temperature at less than 10 DEG C, removing the ice bath after completing the dropwise adding, slowly heating to a room temperature, continuously stirring for 14-20 h, and cooling to a room temperature to obtain a reaction product; adjusting the pH value to be neutral, then separating an organic phase, extracting a water phase by using an organic solvent, combining the organic phases, drying, filtering, and carrying out reduced pressure distillation to obtain N-cyclohexylmethyl carbamate; and step 2, carrying out thermal cracking reaction on the N-cyclohexylmethyl carbamate and a catalyst B, collecting, rectifying and purifying to obtain the cyclohexyl isocyanate. According to the method disclosed by the invention, the cyclohexyl isocyanate is synthesized by adopting a carbamate method, so that environmental hazards caused by phosgene are effectively avoided, and the cyclohexyl isocyanate with high yield and high purity is obtained.

The utility model mainly relates to the field of filtering equipment, and provides material filtering equipment for processing methyl carbamate, which structurally comprises a kettle body, an annular seat is fixedly connected to the top of the inner wall of the kettle body through bolts, and a conical filtering sleeve is fixedly arranged at the bottom of the annular seat. An auxiliary conical sleeve is fixedly connected to the middle of the top end of the conical filter sleeve through a bolt, and a connecting pipe is inserted into the top of the auxiliary conical sleeve; a material pumping pipe is fixedly arranged at the input end of the material pumping pump, an extension pipe is fixedly arranged at one end of the material pumping pipe, a solid-liquid mixture enters the auxiliary conical sleeve, and a solid catalyst at the bottom of the auxiliary conical sleeve is squeezed into a filtering area between the conical filtering sleeve and the auxiliary conical sleeve to be continuously filtered due to the accumulation weight of materials in the auxiliary conical sleeve; at the moment, the solid catalyst pushed to be close to the upper part of the conical filtering sleeve is basically filtered, and is pumped out through equipment such as a material pump, so that dynamic continuous filtering operation of the solid catalyst by the equipment is realized.

The application discloses a zinc-aluminum composite oxide catalyst and a preparation method and application thereof, and belongs to the technical field of catalytic materials and non-phosgene isocyanate preparation. The application solves the problems of high reaction temperature, low raw material concentration, many side reactions and insufficient catalyst stability in the process of preparing isocyanate by pyrolysis of carbamic acid ester. The zinc-aluminum composite oxide catalyst comprises a composite oxide of zinc and aluminum, and has a dual-phase heterogeneous structure of ZnO and ZnAl2O4 spinel. When the catalyst is applied to the preparation of 4-(4'-phenylaminomethylcarbamate) diphenyl methane isocyanate (MMI) and diphenyl methane diisocyanate (MDI) by vacuum thermal decomposition of diphenyl methane diamino methylcarbamate (MDC), the self-polymerization and condensation side reactions in the reaction process can be effectively inhibited by the synergistic effect of the ZnO phase and the spinel phase, the selectivity and yield of the target product are improved, and the catalyst has good mechanical stability and is easy to recycle and cyclically used.

The present invention relates to fungicidal compositions comprising at least one compound selected from the group consisting (I-1) methyl N-[[5-[1-(2,6-difluoro-4-isopropyl-phenyl)pyrazol- 3-yl]-2-methyl-phenyl]methyl]carbamate, (I-2) methyl N-[[5-[1-(4-cyclopropyl-2,6-difluoro- phenyl)pyrazol-3-yl]-2-methyl-phenyl]methyl]carbamate, (I-3) methyl N-[[5-[1-(4-chloro-2,6- difluoro-phenyl)pyrazol-3-yl]-2-methyl-phenyl]methyl]carbamate, (I-4) methyl N-[[5-[1-[2,6- difluoro-4-(trifluoromethyl)phenyl]pyrazol-3-yl]-2-methyl-phenyl]methyl]carbamate, and as active component 2) at least one compound, or an N-oxide, or an agriculturally useful salt thereof, selected from the group consisting of (II-1) 2-fluoro-4-[5-(trifluoromethyl)-1,2,4-oxadiazol-3- yl]benzanilide, (II-2) N-methoxy-N-[[4-[5-(trifluoromethyl)-1,2,4-oxadiazol-3- yl]phenyl]methyl]cyclopropanecarboxamide, (II-3) N,2-dimethoxy-N-[[4-[5-(trifluoromethyl)-1,2,4- oxadiazol-3-yl]phenyl]methyl]propenamide wherein the weight ratio of compound I to compound II is from 10:1 to 1:10. The invention also relates to an agrochemical composition comprising the composition and a solvent of solid carrier. Further, the invention relates to a non-therapeutic use of the inventive compositions controlling phytopathogenic harmful fungi.

The present invention relates to fungicidal compositions comprising at least one compound selected from the group consisting (I-1) methyl N-[[5-[1-(2,6-difluoro-4-isopropyl-phenyl)pyrazol- 3-yl]-2-methyl-phenyl]methyl]carbamate, (I-2) methyl N-[[5-[1-(4-cyclopropyl-2,6-difluoro- phenyl)pyrazol-3-yl]-2-methyl-phenyl]methyl]carbamate, (I-3) methyl N-[[5-[1-(4-chloro-2,6- difluoro-phenyl)pyrazol-3-yl]-2-methyl-phenyl]methyl]carbamate, (I-4) methyl N-[[5-[1-[2,6- difluoro-4-(trifluoromethyl)phenyl]pyrazol-3-yl]-2-methyl-phenyl]methyl]carbamate, and as active component 2) at least one compound, or an N-oxide, or an agriculturally useful salt thereof, selected from the group consisting of (II-1) flumetylsulfurim, (II-2) feneptamidoquin, (II-3) 3-[3-(3- chloro-2-fluoro-phenoxy)-6-methyl-pyridazin-4-yl]-5-[(2-chloro-4-methyl-phenyl)methyl]-5,6- dihydro-4H-1,2,4-oxadiazine, wherein the weight ratio of compound I to compound II is from 10:1 to 1:10. The invention also relates to an agrochemical composition comprising the composition and a solvent of solid carrier. Further, the invention relates to a non-therapeutic use of the inventive compositions controlling phytopathogenic harmful fungi.

The present application relates to a kind of fast curing two-component condensation dealcoholization type silicone glue and preparation method, raw material includes A component: hydroxyl silicone oil or alkoxy silicone oil, filler A, crosslinking agent, coupling agent, catalyst;B component: inert silicone oil, Burgess reagent (N- (triethylammonium sulfuryl) methyl carbamate), filler B.The adhesive curing process organosilicon condensation dealcoholization vulcanization and the effect of synergistic catalysis can be achieved by the reaction of alcohol dehydration into alkene with Burgess reagent as dehydrating agent for alcohol dehydration, ultimately realizes the room temperature fast deep layer curing of dealcoholization type organosilicon adhesive, can realize 4h glue layer curing depth ≥20mm;The adhesive is suitable for the application scene requiring room temperature fast curing or deep layer potting etc., can significantly improve production efficiency.

The invention discloses a plastic packaging material for food and a preparation method of the plastic packaging material. On one hand, the invention provides the plastic packaging material for the food, and the plastic packaging material is prepared from the following raw material components in parts by mass: 60 parts of HDPE (High-Density Polyethylene) resin, 40 to 50 parts of EVOH (Ethylene Vinyl Alcohol) resin, 24 to 32 parts of non-isocyanate polyurethane prepolymer and 6 to 10 parts of cinnamyl aldehyde grafted nano titanium dioxide; the non-isocyanate polyurethane prepolymer is prepared from the following raw material components in parts by mass: 60 to 68 parts of methyl 1, 6-hexamethylene dicarbamate, 6 to 8 parts of bio-based polyol, 10 to 16 parts of eugenol, 1 to 3 parts of ferric oxide and 2 to 4 parts of zinc acetate. On the other hand, the invention provides a preparation method of the plastic packaging material for food. The packaging material disclosed by the invention is excellent in high and low temperature resistance, excellent in solvent resistance and moisture resistance, excellent in oxygen barrier property, free of harmful substance precipitation and relatively excellent in antibacterial property.