98 results about "Dibromomethane" patented technology

An improved method of synthesizing a macrocyclic tetraamido compound includes protecting the amino portion of an amino carboxylic acid to form a protected amino carboxylic acid; exposing the protected amino carboxylic acid to a first solvent, preferably a hydrocarbon solvent, such as toluene or 1,2-dichloroethane, dichloromethane, dibromomethane and 1,2-dibromoethane. The carboxylic acid portion of the protected amino carboxylic acid is then converted to an activated carboxylic acid by one of esterification or acid halide formation, to form a protected amino activated carboxylic acid derivative. The protected amino activated carboxylic acid derivative is reacted with a diamine in the presence of a second solvent, such as THF or ,2-dichloroethane, dichloromethane, dibromomethane and 1,2-dibromoethane, to form a protected diamide diamine intermediate. Following deprotection, the diamide diamine intermediate is reacted with an activated diacid, such as an activated malonate, oxalate or succinate derivative to form the macrocyclic tetraamido compound. The macrocyclic tetraamido compound may further be complexed with a transition metal.

The invention relates to an aluminum alloy door and window protection coating layer material used for smart homes. The material comprises melamine copolycondensation resin, fluoroether rubber, modified phenolic resin, nanometer zinc oxide, potassium titanate whisker reinforcement, nanometer magnesium hydroxide, polyethylene wax, zinc pyrithione, 10,10'-oxybisphenoxarsine, carbendazim, tetramethylthiuram disulfide, dibromomethane, titanium nitride powder, zeolite powder, sodium dihydrogen phosphate, disodium hydrogen phosphate, barium sulfate powder, lead oxide powder, barite powder, molybdenum disulfide powder, sodium carbonate, lead iodate powder, diethylene glycol butyl ether, soybean oil, amyl acetate, petroleum sulfonate, vinyl benzene, cobalt isooctoate, sulfamic acid and isopropyl titanate. The material has superior flame, acid-alkali, mildew and bacterium resistance, and improved performances.

The invention discloses a method for preparing dibromomethane and bromochloromethane by a kettle method, which adopts the following processes: hydrogen bromide and dichloromethane react to obtain dibromomethane; methanol is reacted with water to obtain pure hydrogen; the hydrogen is then reacted with bromine to obtain hydrogen bromide gas; the hydrogen bromide gas is then purified until the purity is above 98 percent, thus ensuring that the side effect brought to the reaction by the hydrogen can be reduced to the lowest; the hydrogen bromide gas and the dibromomethane are added into a reaction kettle for reaction; after the operations of washing, distilling, and the like, the dibromomethane and bromochloromethane with high purity can be obtained from reactants; the dichloromethane is used for the combined production of dibromomethane and bromochloromethane, which is the most direct and economical way, and the method is characterized by no introduction of other impurities, no by-products, the high quality of products and no pollution of three-waste.

The invention discloses a process for producing thiabendazole. The process includes carrying out condensation reaction on lactic acid and o-phenylenediamine in acidic aqueous solution(with, but not limited to, hydrochloric acid); regulating pH (potential of hydrogen) values to obtain 2-alpha-hydroxyl ethyl benzimidazole; placing the 2-alpha-hydroxyl ethyl benzimidazole in a container with acetone and sulfuric acid (but not limited to sulfuric acid, or hydrochloric acid and other inorganic acid and strong acid and weak alkali salt) and carrying out oxidation reaction on the 2-alpha-hydroxyl ethyl benzimidazole and potassium permanganate (but not limited to potassium permanganate, or hydrogen peroxide and organic peroxide); carrying out extraction, desolvation and drying to obtain 2-acetyl benzimidazole; placing the 2-acetyl benzimidazole in a container with glacial acetic acid and carrying out halogenations reaction on the 2-acetyl benzimidazole and bromine (but not limited to, or chlorine and other halogens); drying filter cake to obtain 2-dibromomethane acetyl benzimidazole hydrobromide; carrying out reaction on formamide and phosphorus pentasulfide in a container with ethyl acetate to obtain thioformamide; removing phosphorus pentoxide by means of filter-press by the aid of nitrogen to obtain thioformamide/ethyl acetate solution and carrying out cyclization reaction on the thioformamide/ethyl acetate solution and 2-dibromomethane acetyl benzimidazole; purifying reaction products and regulating pH (potential of hydrogen) values to obtain the thiabendazole with the content higher than or equal to 99%. The acetone and the sulfuric acid in the corresponding container are used as solvents. The glacial acetic acid in the corresponding container is used as a solvent. The ethyl acetate in the corresponding container is used as a solvent. The process has the advantages that the cost can be lowered, risks in the aspects of safety and environmental protection can be reduced, environmental pollution can be abated, and the production efficiency can be improved; integral reaction procedures are carried out at the normal temperatures under the normal pressures, accordingly, reaction conditions are mild, the yield of the reaction at each step is quite stable, and the overall yield measured by the aid of the o-phenylenediamine can reach 75% at least.

This invention relates to a preparation of methylene diphosphonate tetro-ethyl ester. Dibromomethane and triethyl phosphate are mixed according to gram-molecule ratio 1:2-1:3,then first progress low temperature reaction at 85-100 C degree about 30-40 minutes, and it is reheated to 175-190 C degree to progress hyperthermic response about 18-24 hours, condensed to prepare methylene diphosphonate tetro-ethyl ester.

The invention discloses a synthetic method of strigolactone (+/-)-GR24 and 4-substituted (+/-)-GR24. The method comprises the following steps: benzoic acid which is used as a raw material reacts with dibromomethane to obtain an intermediate as shown in the formula I; the intermediate I undergoes diisobutylaluminium hydride reduction to obtain an intermediate as shown in the formula II; the intermediate II and (2-carboxyethyl)triphenylphosphonium bromide undergo coupling under the action of alkali so as to obtain an intermediate as shown in the formula III; the intermediate III reacts with Dess-Martin periodinane to obtain an intermediate as shown in the formula IV; the intermediate IV undergoes cyclization under the action of an acid catalyst or reacts with a nucleophilic reagent so as to obtain ABC tricyclic lactone, namely an intermediate as shown in the formula V; the intermediate V and ethyl formate undergo a formylation reaction to obtain an intermediate VI; and the intermediate VI and bromobutenolide undergo coupling so as to obtain (+/-)-GR24 and 4-substituted (+/-)-GR24. The raw materials used in the synthetic method are cheap and easily available; the operation is simple; reaction conditions are mild; safety is high; the catalyst used in the invention is environment-friendly; tricyclic lactone can be constructed by one-step tandem cyclizaiton reaction; the reaction route is short; and overall yield is high. Thus, total cost is greatly reduced. The synthetic method meets requirements of mass synthesis.

The invention discloses a method for synthesizing fludioxonil intermediate 4-aldehyde-2,2-difluorobenzodioxole. The method comprises the following steps of: performing o-orientating formylation on o-cresol serving as an initiative raw material to obtain 3-methylsalicylaldehyde, converting the 3-methylsalicylaldehyde into 3-mehtylpyrocatechol through Dakin reaction, directly reacting the 3-mehtylpyrocatechol with dichloromethane or dibromomethane to generate 4-methylbenzodioxole without separation and purification, and performing three-step reaction of chlorination, fluoro and oxidation on the 4-methylbenzodioxole to generate a product. The cheap o-cresol is used as the initiative raw material, and the obtained 3-mehtylpyrocatechol directly enters the next reaction without separation, so the production cost is greatly reduced; phosphorus pentachloride is used as a chlorination reagent in the chlorination link so as to avoid the use of chlorine and reduce the risk of causing environmental pollution; and the methyl is converted into aldehyde group through the oxidation reaction so as to avoid a route of chlorination hydrolysis, simplify the operation, reduce the environment-friendly pressure and gain higher economic value and social meaning.

The disclosure relates to a plasma etch chemistry which allows a near perfectly anisotropic etch of silicon. A Cl-based plasma etch such as SiCl₄+Cl₂ has CH₂Br₂ added thereto, readily allowing the anisotropic etching of silicon. The silicon surface facing the discharge is subjected to ion bombardment, allowing the volatilization (etching) of silicon as a Si—Cl—Br compound. The Br which adsorbs on the sidewalls of the etched silicon passivates them from the etching. This new plasma etch chemistry yields a very smooth etched surface, and the etch rate is relatively insensitive to the electrical conductivity of the silicon. The use of dibromomethane is an improvement over the prior art which typically used HBr; a poisonous and ozone depleting gas. Dibromomethane is a relatively safe gas and not ozone depleting, yet giving substantially similar results in plasma etching of silicon, silicon nitride, and other materials.

The invention belongs to the field of the synthesis of anti-hepatitis C virus medicines by using medical intermediates, and particularly relates to an asymmetric synthesis method of a medical intermediate 2-azabicyclo [3. 1. 0] hexane-2, 3-tert-butyl dicarbonate. The asymmetric synthesis method is mainly characterized in that (2R) or (2S)-1, 2-tert-butyl dicarbonate-2, 3-pyrrole alkene is used as a raw material, methylbenzene, benzene or trihalomethylbenzene is used as a solvent, diiodomethane, chlorobromomethane, dibromomethane or diethylzinc is used as a cyclopropanation reagent, and after reaction, the compound 2-azabicyclo [3. 1. 0] hexane-2, 3-tert-butyl dicarbonate is obtained. The asymmetric synthesis method has the advantages that synthesis steps are simple, the yield is high, the cost is low, the cyclopropanation reagent is wide in selectivity, the synthesis process is simple, convenient and practical, and the like.

The invention discloses a hardware stamped part. The hardware stamped part is coated with a protection coating. The protection coating comprises, by weight, 23 parts of polyester resin with active methyl groups, 4 to 5 parts of dibromomethane, 2 to 3 parts of precipitate barium sulfate, 5 to 6 parts of dibutyltin dilaurate, 1 to 2 parts of titanium dioxide and 3 to 4 parts of bentonite. The hardware stamped part provided by the invention has the advantages of high strength, wear resistance and corrosion resistance.

The invention discloses waterproof paint not liable to peel off. The paint is prepared from following raw materials by weight: 2.5-3.8 parts of dibromomethane, 3.5-3.7 parts of tetrahydrofuran, 3.5-4.7 parts of nonylphenol polyoxyethylene ether, 3-7 parts of kaolin, 1.2-1.7 parts of phenylethyl naphthol polyoxyethylene ether, 2.5-5 parts of octadecanol polyoxyethylene ether, 1.2-2.2 parts of N-methyl-alkylamido taurine salt and 1.8-3.6 parts of a sorbitol-fatty acid ester. Compared with waterproof paint at present, the paint provided by the invention has high water resistance, high water proofness and high tensile strength and is healthy and environmental friendly; environment pollution is reduced and wall peeling off caused by rain wash after longtime use is avoided; the paint provided by the invention can prevent being washed by acid rain; and the paint film wound not peel off after rain wash, thus reducing the probability that rain permeates into the wall and corrodes the wall to cause losses.

The invention belongs to an olefinic polymerization catalyst technical field, especially an olefinic polymerization catalyst of carbene nickel series containing sulfur family element and preparation method thereof and application. The catalyst is represented by formular: [L-NiBr2], wherein L represents double teeth ligand containing substituent sulfur or selenium carbene type which can coordinate with metal. Dibromomethane or dibromoethane and substituent imidazole are used as start material, and the double teeth ligand containing substituent sulfur or selenium carbene type is obtained after a series of reaction steps/ The ligand is respectively reacted with di(triphenyl phosphor) nickel dibromide of one molar mass, and then subjected to filtering, cleaning, and vacuum pumping and drying to finally obtain the corresponding nickel catalyst. The catalyst is coordinated with co-catalyst MAO or MMAO and used for catalysing the addition polymerization of norborene, with high catalytic activity. The invention has features of simplicity, good stability. The obtained polynorbornene product has high molecule weight, high glass-transition temperature and fine solubleness.

The invention relates to a preparation method of a nysted reagent. The preparation method comprises the following steps of: (1) adding zinc powder to a methanol solvent under the protection of nitrogen, dropwise adding alcohol solution of hydrogen chloride under the condition of stirring for reacting at the reflux temperature to activate the zinc powder, cooling to be at the room temperature to separate clear liquid with solid, heating the solid, reducing pressure and evaporating the solid to be dry through a water pump to prepare the activated zinc powder; (2) adding the activated zinc powder and a copper catalyzer to the organic solvent, dropwise adding dibromomethane slowly for reacting at the reflux temperature, cooling to be at the room temperature, dropwise adding the dibromomethane for the second time, and stirring at the room temperature until the zinc powder is reacted completely to obtain milky turbid liquid, namely the nysted reagent. According to the preparation method, the activated zinc powder is synthetized to the nysted reagent on the premise of existence of the catalyzer, the method is simple and practical and is easy to operate, the cost of raw materials is low, the economic benefit is good, the pollution to the environment is low, the yield is improved due to the use of the catalyzer, and the final yield achieves more than 90%. The preparation method is suitable for mass industrial production.

An unwanted tungsten film deposit on a Chemical Vapor Deposition chamber is cleaned by adding a mixture of at least two cleaning gases into the chamber at a predetermined temperature and pressure and in contact with said chamber walls for a sufficient length of time. The cleaning gases and reacted tungsten species are removed from the chamber by vacuum, and unreacted cleaning gases are removed by purging the chamber with an inert gas. At least one cleaning gas is selected from the group consisting of bromomethane, dibromomethane, bromoform and mixtures thereof. The temperature of the chamber is preferably at least about 300 degrees Celsius. The cleaning gases in the chamber are at a pressure in the range from about 100 to 200 Torr and the chamber is purged at a pressure in the range from about 200 to 500 Torr.

The invention relates to a multifunctional cable for municipal ecological garden construction. The multifunctional cable comprises a plurality of copper alloy wires and protecting covers, the copper alloy wires are arranged in parallel, and the outer layers of all the copper alloy wires are covered with the protecting covers. The protecting covers are prepared from p-tert-octyl phenolformaldehyde resin, fluorosilicon resin, fluororubber, pure acrylic emulsion, butyl acetate, lauryl alcohol phosphate acid ester, spindle oil, dipropylene glycol methyl ether, sodium monofluorophosphate, ethyl p-hydroxybenzoate, didecyl dimethyl ammonium chloride, dibromomethane, corn starch, sodium phosphate, calcium sulphate dehydrate, glass fiber powder, aluminium nitride powder, sodium tetraborate decahydrate, quartz powder, magnesium sulfate, polyethylene wax, trioctyl phosphate, polychlorinated biphenyl, ammonium polyphosphate, sodium ricinoleate, butyraldehyde, polyethylene polyamine, nickel dibutyldithiocarbamate, chlorothalonil and lead sulfate tribasic. By means of the multifunctional cable for municipal ecological garden construction, the using performance of the product is improved.

The invention discloses novel anticorrosive paint. The novel anticorrosive paint is prepared from 18-20 parts of silver powder, 10-18 parts of copper powder, 15-18 parts of iron powder, 20-28 parts of glass powder, 10-15 parts of magnesium powder, 20-25 parts of microcrystalline silicon powder, 15-18 parts of nano carbon particles, 5-6 parts of dibromomethane, 3-5 parts of sodium bicarbonate, 30-45 parts of crylic acid emulsion, 30-35 parts of organic silicone oil, 12-15 parts of iron boride, 20-25 parts of dolomite powder, 15-20 parts of kaolin, 18-20 parts of bentonite, 8-10 parts of alumina silicate fibers, 8-10 parts of glass beads, 10-12 parts of polyvinyl alcohol, 6-8 parts of hydroxyethyl cellulose, 6-8 parts of aluminum-magnesium silicate and 120-150 parts of deionized water. According to the novel anticorrosive paint, the abrasion resistance and corrosion resistance of a coating are improved, the advantages of being high in strength, large in specific area, high in chemical reaction activity and high in fillibility are achieved, the coating and a bottom material are in contact more tightly, the lubricating effect is good, and the abrasion resistance of the coating can be improved. The novel anticorrosive paint has electrochemical inertness, is attached to the surface of a zinc sheet and the surface of an aluminum sheet, therefore, the novel anticorrosive paint is beneficial for a zinc-aluminum cathodic protection reaction, and the anti-corrosion time can be prolonged.

The invention discloses a preparation method of methane disulfonic acid. The preparation method comprises following steps: in the presence of a composite phase transfer catalyst, reacting sulfites with dibromomethane in water to obtain methane disulfonate; and carrying out acidification to obtain methane disulfonic acid; wherein the composite phase transfer catalyst comprises polyethylene glycol and other phase transfer catalysts other than polyethylene glycol; and other phase transfer catalysts are one or more of tetramethyl ammonium bromide, tetramethyl ammonium chloride, tetraethyl ammoniumbromide, tetraethyl ammonium chloride, tetrabutyl ammonium bromide, tetrabutyl ammonium chloride, benzyl triethyl ammonium chloride, cetyl trimethyl ammonium bromide, 18-crown-6, 15-crown-5, cyclodextrin, pyridine, and triethylamine. The preparation method can be performed at a low temperature under a normal pressure, is more environmentally-friendly, reduces energy consumption, and has the advantages of simple operation, safety, and ideal yield.

The invention discloses a method for preparing clodronate disodium. The method comprises the following steps of: performing methylenation, chlorination, acid hydrolysis and salification on triethyl phosphate and dibromomethane which serve as raw materials to obtain the clodronate disodium. According to the method, the clodronate disodium is produced by taking triethyl phosphite is used as the raw materials, so that the cost of the raw materials is reduced substantially, the method is easy to operate, and industrial production is easy to implement; derosination reaction of an intermediate II is performed by an acid hydrolysis method, the reaction condition is mild, the reaction time is shortened to 1 to 3 hours from 10 hours, and the production efficiency is improved greatly; the purity of the product and the clarity of a solution are high, so the clodronate disodium can be used for preparing high-quality clodronate disodium injections and clodronate disodium capsules, and the risk of clinical medication is reduced; and hydrochloric acid and other organic solvents which are used in the process can be recycled, so the method is environment-friendly.

The invention relates to a preparation method of a special gas, in particular to a preparation method of an electric light source gas containing dibromomethane. A gravimetric method is adopted for preparation, a dibromomethane liquid sample is weighed quantitatively at room temperature, the temperature is increased to 70-80 DEG C and kept constant for 8-12 min, after the liquid sample is completely evaporated, balance gas is used for performing voltage transformation purging on the dibromomethane gas to a product steel cylinder, finally the steel cylinder is filled with the balance gas to the product pressure being P, mixing is performed, the actual concentration of the product is obtained through calculation, preparation is completed, and the balance gas is xenon or krypton. The method can solve the problem that the concentration of the electric light source gas does not reach the standard due to the fact that dibromomethane is easily stuck to a vessel wall, and remarkably improve the yield and product concentration uniformity of the electric light source gas containing dibromomethane.

The invention discloses a method for synthesizing diphenoxyl methane, comprising the following steps of: adding and strongly stirring potassium hydroxide to fused phenol, then slowly dropwise adding dibromomethane after stirring for ten minutes, stirring and making the mixture react for 2-5 h at 80-100 DEG C, extracting a reactant by using diethyl ether, and distilling to obtain a residual oily liquid which is the diphenoxyl methane. The method for synthesizing diphenoxyl methane is carried out at low temperature and normal pressure and has simple and easy operation and 100% of selection, andthe synthesized diphenoxyl methane has high purity and stable performance; and the invention provides a new approach for converting the diphenoxyl methane.