38 results about "Boron tribromide" patented technology

The invention discloses an antistatic fabric and a preparation method thereof, and relates to the technical field of fabrics. When the antistatic fabric is prepared, firstly, polyamide is grafted with 2-chloro-6-vinylpyridine under the action of an initiator, then the polyamide reacts with 2-amino-4-methoxypyrimidine-5-boronic acid pinacol ester, methoxyl is removed through boron tribromide, then the polyamide reacts with 2-diphenylphosphinobenzaldehyde, and modified polyamide is obtained; secondly, grafting tea polyphenol on the multi-walled carbon nanotube which is firstly treated by nitric acid and then treated by thionyl chloride, and then reacting with 4-[2, 2 ': 6', 2 ''-terpyridyl]-4 '-yl-thiophenol to obtain a modified multi-walled carbon nanotube; and finally, carrying out melt spinning on the modified polyamide, the modified multi-walled carbon nanotubes and the antibacterial agent to obtain antistatic fibers, and weaving the antistatic fibers to obtain the antistatic fabric. The antistatic fabric prepared by the invention has excellent flame retardance, electrical conductivity, ultraviolet resistance and oxidation resistance.

The invention relates to a preparation method of a polyester film based on full-hydroxyl column [5] arene. The polyester film with salt separation is prepared by taking full-hydroxyl column [5] arene as a water-phase monomer through an interfacial polymerization method. The method comprises the following steps: (1) synthesizing methoxy pillar [5] arene from 1, 4-dimethoxybenzene and paraformaldehyde under the catalysis of boron trifluoride diethyl etherate; (2) reacting the purified product with boron tribromide, and removing methyl groups to obtain full-hydroxyl column [5] arene; (3) dissolving the product in an aqueous solution containing triethylamine, and forming a two-phase solution of interfacial polymerization reaction with an n-hexane solution of trimesoyl chloride; and (4) sequentially coating the surface of the polyacrylonitrile ultrafiltration membrane with the aqueous phase solution and the organic phase solution, and carrying out interfacial polymerization reaction to obtain the polyester membrane. Based on the inherent cavity and polyhydroxy characteristics of the full-hydroxyl column [5] arene, compared with a traditional polyamide membrane, the obtained polyester membrane has high permeability and selectivity, can efficiently separate dye and inorganic salt, and is suitable for water treatment processes of printing and dyeing wastewater and the like.

The invention discloses a preparation method of water-soluble naphthyl nut arene and construction of a molecular beaker. The method comprises the following steps: reacting 2, 7-dibromonaphthalene (compound 1) with 2, 5-dimethoxyphenylboronic acid to generate a compound 2; demethylating through boron tribromide to obtain a compound 3; then reacting with dihaloalkane to generate a compound 4; then carrying out cyclization with methylal to obtain H1; then reacting with trimethylamine to obtain H2; then, H2 and sodium phytate are used for constructing a molecular beaker system; according to the method, a series of water-soluble naphthyl nut arenes with different alkane chain lengths and different halide ions are prepared, and an efficient molecular beaker system is constructed. The molecular beaker system has the advantages of being simple and convenient to synthesize, low in cost, adjustable in height, capable of effectively improving the binding capacity with specific guest molecules and the like.

The present application relates to the field of medicine synthesis, and discloses a preparation method and application of brominated piperonal carboxylic acid, wherein the brominated piperonal carboxylic acid compound is prepared from o-vanillin as a starting material through acetyl protection, bromination reaction, deprotection and demethylation reaction, cyclization reaction and Pinnick oxidation reaction.No longer through a brominated piperonal intermediate, and without using a live LDA reagent low-temperature lithiation reaction, the safety and stability are greatly improved.The deprotection and demethylation reaction is carried out in one pot, and the use of boron tribromide and other reagents is avoided;finally, the oxidation step from aldehyde to acid avoids using traditional silver oxide or potassium permanganate oxidation, and adopts Pinnick oxidation, which is economic, environmental protection and cost reduction, and greatly improves the yield.The whole has the advantages of easy-to-obtain raw materials, short steps, mild reaction conditions, low production cost, environmental protection, high yield and high purity, and can meet the high quality requirements of pharmaceutical products.

The invention discloses a preparation method of a cyanoborate lithium salt derivative, which comprises the following steps: 1, mixing an alcohol compound, a lithium source compound, a boron source compound and trimethylsilyl cyanide in a polar organic solvent, and filtering after complete reaction to obtain a cyanoborate crude product filtrate; the alcohol compound is selected from one of 2, 2, 2-trifluoroethanol, 2, 2-difluoroethanol, 2-fluoroethanol, 3-hydroxypropionitrile, allyl alcohol and propargyl alcohol; the lithium source compound is selected from one of lithium carbonate and lithium hydroxide; the boron source compound is selected from one of boric acid, diboron trioxide and boron tribromide; the reaction temperature is controlled to be 0-120 DEG C; and 2, adding an inert organic solvent into the cyanoborate crude product filtrate for crystallization, and performing vacuum drying to obtain a finished product of the cyanoborate lithium salt. The method has the advantages of high yield and purity, simple process, convenience in operation and low cost, and is extremely suitable for industrial production.

The invention belongs to the field of superoxide anion free radical detection, and particularly relates to a reversible fluorescent probe for detecting superoxide anion free radicals as well as a synthesis method and application of the reversible fluorescent probe. The fluorescent reversible probe is 3-(benzothiazole-2-yl)-[1, 1 '-biphenyl]-2, 3', 4 '-triphenol. The preparation method comprises the following steps: dissolving 3-bromo-2-hydroxybenzaldehyde in absolute ethyl alcohol, adding sodium hydrogen sulfite and o-aminothiophenol, and carrying out heating reflux reaction; dissolving a reaction product and 3, 4-dimethoxyphenylboronic acid in tetrahydrofuran, adding a potassium carbonate solution and tetrakis (triphenylphosphine) palladium, and carrying out heating reflux reaction; and dissolving the product obtained by the reaction in dichloromethane to completely dissolve the solid, adding boron tribromide, and reacting under the ice salt bath condition to obtain the target probe. The fluorescent reversible probe can be used for superoxide anion free radical detection, and the detection method is simple, convenient to operate, good in selectivity, high in sensitivity, long in emission wavelength, large in Stokes shift and high in signal-to-noise ratio.

The invention provides a novel method for preparing an intermediate compound of aromatic sesquiterpenes Commiphoranes C-D. The method comprises the following steps: substituting the ortho-position of a compound 1 with iodine through n-butyllithium and diiodoethane to obtain a compound 2; removing methoxyl by using boron tribromide to obtain a compound 3; performing nucleophilic substitution on 3-allyl bromide and potassium carbonate to synthesize a compound 4; carrying out Grignard reaction to obtain a compound 5; oxidizing into a compound 6 through a Dess-Martin oxidizing agent; finally, (CH3Si) 3SiH and triethyl boron are subjected to intramolecular free radical series cyclization, so that synthesis of an aromatic sesquiterpene Commiphoranes C-D intermediate compound is successfully completed, sufficient preparation is made for follow-up total synthesis of the natural product, key intramolecular free radical series cyclization has the capacity of efficiently constructing a polycyclic system, and the synthesis process is simple and convenient. According to the preparation method, the defects of expensive reagents, long 14-step linear synthesis route, low yield and the like in the existing synthesis route are overcome; the popularization potential is high.

The present invention provides a preparation method of (2-fluoro-6-hydroxyphenyl) potassium trifluoroborate. The preparation method comprises the following steps: (1) reacting 3-fluorophenol and chloromethyl ether to obtain a compound shown in Formula I; (2) in the presence of a lithium reagent, reacting the compound shown in Formula I obtained in step (1) with isopropyl alcohol pinacol borate to obtain a compound shown in Formula II; (3) in the presence of an acid, reacting the compound shown in Formula II obtained in step (2) with potassium fluoride to obtain (2-fluoro-6-hydroxyphenyl) potassium trifluoroborate. The preparation process of the present invention does not require the use of a hazardous reagent, boron tribromide, and the yield is also greatly improved, the process is simple, convenient to operate, and is easy to industrialize.

The invention belongs to the technical field of zinc ion batteries, and particularly relates to a hexahydroxy truxene organic positive electrode material for an aqueous zinc ion battery, a preparation method and application. According to the method, 5, 6-dimethoxy indanone is taken as a raw material, p-toluenesulfonic acid is taken as a catalyst, ethylene glycol is taken as a cocatalyst, 2, 3, 7, 8, 12, 13-hexamethoxy truxene is efficiently synthesized through a water diversion reflux reaction, and then a target product 2, 3, 7, 8, 12, 13-hexahydroxy truxene is obtained through a boron tribromide demethylation reaction. According to the method, the defect that a traditional polyphosphate (PPE) catalyst synthesis process is tedious is overcome, meanwhile, the technical problem that a trimerization product cannot be prepared by replacing an acid catalyst is solved, and the prepared hexahydroxy truxene material is of a nanorod-shaped structure, has excellent cycling stability and high specific capacity when serving as an aqueous zinc ion battery positive electrode material and is suitable for being used as a water-based zinc ion battery positive electrode material. The material can adapt to high-rate charge and discharge, and the overall electrochemical performance is excellent.

The invention relates to a compound MDMB-BUTINACA-D3 as well as preparation and application thereof, and the structural formula of the compound MDMB-BUTINACA-D3 is as follows: 2-(1H-indazole-3-formamido)-3, 3, 4-triazole-3-carboxylic acid is obtained through condensation reaction of indazole-3-carboxylic acid and tert-leucine methyl ester hydrochloride; the preparation method comprises the following steps: adding 2-(1H-indazole-3-formamido)-3, 3-dimethyl butyric acid methyl ester into 2-(1H-indazole-3-formamido)-3, 3-dimethyl butyric acid methyl ester, adding 3-phenoxybromopropane into a Grignard reagent, carrying out a substitution reaction to obtain butoxybenzene-D4, further adding a brominating agent boron tribromide, carrying out a bromination reaction to obtain bromobutane-D3, and finally carrying out a substitution reaction on 2-(1H-indazole-3-formamido)-3, 3-dimethyl butyric acid methyl ester and bromobutane-D3 again to obtain MDMB-BUTINACA-D3. According to the method, the matrix effect can be well avoided, meanwhile, mass spectrum cross signal overlapping caused by natural isotopes can be avoided, and the mass spectrum quantitative analysis precision can be remarkably improved when the method is used as an internal standard substance for MS quantitative determination.

The invention relates to the technical field of conductive coatings, in particular to an aircraft fairing surface conductive coating and a preparation method thereof. The conductive coating is prepared from the following raw materials: conductive phthalonitrile, N, N-dimethylformamide, a dispersing agent BYK-110, 3-aminopropyltriethoxysilane, a flatting agent BYK-333 and a de-foaming agent BYK-066N; wherein the conductive phthalonitrile is prepared by the following steps: removing methoxyl by boron tribromide to prepare a hydroxyl thienopyrroledione intermediate, then reacting 5-bromo-2-fluoroaniline with 4, 4-dihydroxyl stilbene to obtain a monomer A, and subsequently reacting with hydroxyl thienopyrroledione and 4-nitro-2-trifluoromethyl-phthalonitrile to purify, thereby obtaining the conductive phthalonitrile. After the paint is prepared, a coating is formed through stepped heating curing and three-time spraying. The conductive coating achieves accurate balance of static dissipation and radar permeability, is compact in structure and high in adhesive force, can resist high and low temperature circulation and salt spray corrosion, and has excellent performance and engineering practicability.

The invention discloses an alkyl-substituted free radical polymer based on 3, 4-dimethoxythiophene and a preparation method of the alkyl-substituted free radical polymer. The preparation method comprises the following steps: dissolving 3, 4-dimethoxythiophene in an organic solvent A, adding an aldehyde substance and boron trifluoride diethyl etherate, heating to 50-120 DEG C, and reacting for 2-20 hours; after the reaction is finished, quenching, extracting with an organic solvent B which is immiscible with water, collecting an organic phase, concentrating, purifying, and filtering, washing and drying the obtained product to obtain a polymer intermediate; dissolving the polymer intermediate in an organic solvent E, stirring at normal temperature, adding boron tribromide, and reacting for 0.5-12 hours; and after the reaction, quenching, filtering, washing and drying. The polymer disclosed by the invention has a strong free radical effect, is beneficial to improving the ionic conductivity and mobility, and can be applied to the fields of coating layers of organic photoelectric devices and lithium ion battery positive electrode materials and the like.

The novel vaporization kettle for boron tribromide processing comprises a kettle body, a protective shell is arranged on the outer side of the kettle body, supporting legs are connected to the two sides of the bottom of the protective shell, and a heat preservation plate is laid on the inner side wall of the protective shell; the two sides of the bottom of the kettle body are connected with the inner bottom of the protective shell through a base, the left upper end of the kettle body is connected with a gas exhaust pipeline, a feeding pipeline is inserted into the right upper end of the kettle body, and the upper end of the gas exhaust pipeline sequentially penetrates through a heat preservation plate and the protective shell from bottom to top and extends upwards; the upper end of the feeding pipeline sequentially penetrates through the heat preservation plate and the protective shell from bottom to top and extends upwards. According to the vaporization kettle, the heat preservation plate, the protective shell and the supporting legs are arranged and are matched with one another, so that the heat preservation and heat insulation performance of the vaporization kettle is improved, heat dissipation is slow, and the energy-saving effect is achieved.

The invention discloses a novel synthetic method of naphthazarin, which comprises the following steps of: 1, reacting 1, 4, 5, 8-tetramethoxynaphthalene with boron tribromide or aluminum trichloride, crystallizing to obtain a high-purity product, and distilling a solvent under reduced pressure to obtain 5, 8-dihydroxy-2, 3-dihydronaphthalene-1, 4-diketone; 2, 5, 8-dihydroxy-2, 3-dihydronaphthalene-1, 4-diketone is added into another reaction kettle, an alkali solution is added, an oxygen micro-positive pressure (0.01-0.03 MPa) is performed for a reaction, and after the reaction is finished, high-purity 5, 8-dihydroxy-2, 3-dihydronaphthalene-1, 4-diketone salt is obtained through ethanol crystallization and filtration; and adding the salt of the 5, 8-dihydroxy-2, 3-dihydronaphthalene-1, 4-diketone into another reaction kettle, adding a hydrochloric acid ethyl acetate solution, heating and reacting, and then filtering and pulping to obtain a final product. The total preparation yield gt of naphthazarin; the HPLC purity is gt; the yield is 99.6%. The route is simple and convenient to operate and easy to implement, raw materials are cheap and easy to obtain, reaction conditions are mild, high-temperature and high-pressure reaction is not needed, and requirements on equipment are reduced. The whole route is safer to the environment, and green and pollution-free production can be realized.

The invention relates to the technical field of organic synthesis, and discloses a synthesis method of 2-cyano-5-fluorobenzyl bromide, which comprises the following steps: mixing a compound I with sulfuric acid, adding potassium bromate, reacting, adding water, layering, distilling and purifying to obtain a compound II; mixing the compound II, cuprous cyanide and DMF, carrying out reflux reaction under stirring, cooling, adding water, extracting and filtering with ethyl acetate, layering, washing with water, desolventizing, and recrystallizing and purifying with methanol to obtain a compound III; mixing the compound III, tetrahydrofuran, water and methanol, dropwise adding a mixed solution of potassium borohydride, water and methanol while stirring, adding water, layering, extracting, desolventizing, cooling to separate out a solid, and filtering to obtain a compound IV; and mixing the compound IV, DCM and DMF, dropwise adding boron tribromide in batches while stirring, adding water, layering, desolventizing, cooling to separate out a solid, and filtering to obtain the 2-cyano-5-fluorobenzyl bromide. The method is reasonable in design route, short in synthesis route, high in safety coefficient and suitable for industrial production.

The invention relates to a piperidine functionalized ring-containing polyfluorene ether ketone anion exchange membrane and a preparation method thereof. The preparation method comprises the following steps: reacting tetramethyl bisphenol fluorene with excessive 4, 4 '-difluorobenzophenone to generate an ABA type compound containing four methyl groups, performing cyclization reaction on the ABA type compound and tetramethyl dimethoxy bisphenol fluorene in a dilute solution to obtain a dimethoxy group-containing cyclic compound, reacting the dimethoxy group-containing cyclic compound with boron tribromide to prepare a cyclic monomer containing two phenolic hydroxyl groups, and reacting the cyclic monomer with 4, 4'-difluorobenzophenone to obtain a dimethoxy group-containing cyclic monomer. The preparation method comprises the following steps: carrying out polycondensation on 4, 4 '-difluorobenzophenone and bisphenol fluorene at a high temperature to prepare a ring-containing polyfluorene ether ketone compound, brominating methyl in the ring-containing polyfluorene ether ketone compound by utilizing bromination reaction, reacting with N-methylpiperidine to prepare a piperidine functionalized ring-containing polyfluorene ether ketone compound, and carrying out solution casting to obtain the anion exchange membrane. The obtained anion exchange membrane has the advantages of high ion conductivity, low vanadium ion permeability, high mechanical strength and the like.

The invention discloses a synthetic method of (R)-glabridin with high optical purity, and belongs to the technical field of organic synthesis. The synthesis method provided by the invention comprises the following steps: dissolving methyl-protected isoflavone in a solvent, and adding boron tribromide to carry out a protecting group removal reaction; then carrying out asymmetric hydrogen transfer reaction on a reaction product in an acid-base mixed solution under the action of a chiral ruthenium catalyst; and finally, in the presence of acid, carrying out dehydroxylation reaction on the reaction product and a silane reagent in a solvent to obtain the (R)-glabridin. The (R)-glabridin is efficiently synthesized with high selectivity through a simple three-step reaction, the total yield is high, the optical purity is excellent, the conditions are mild, the post-treatment method is simple, and the method is suitable for large-scale production.

The invention relates to the technical field of coatings, and discloses a method for preparing a modified phenolic resin coating, wherein the amino group in 3,3-dimethoxy-4,4-diaminobiphenyl reacts with CH3(CH2) n The carboxyl group in COOH undergoes an amidation reaction to obtain 3,3-dimethoxy-4,4-dialkylamide biphenyl, and the obtained product is demethoxylated under the catalysis of boron tribromide to obtain 4,4-dialkylamide biphenyl diphenol. Polyformaldehyde, phenol, 4,4-dialkylamide biphenyl diphenol, etc. are polymerized under alkaline conditions to obtain a modified phenolic resin. Finally, a leveling agent, hydroxyethyl cellulose, an emulsifier, etc. are added to the modified phenolic resin for high-speed dispersion to obtain a modified phenolic resin coating. The phenolic resin coating prepared by the present invention has excellent mechanical properties.

The invention discloses a synthetic method of bisabolane sesquiterpenes and derivatives thereof, and belongs to the technical field of chemical synthesis. The preparation method comprises the following steps: carrying out MOM protection on a phenolic hydroxyl group by using a cheap and easily available compound 1, carrying out benzyl bromination, sodium acetate hydrolysis, benzyl alcohol MOM protection, Grignard reagent addition and Burge reagent elimination, and removing an MOM protecting group under an HCl condition to obtain the natural product Aspergillus A. The method comprises the following steps: carrying out Wolff-Kishner-Huang reduction on a cheap and easily available compound 10, removing a methyl protecting group by using boron tribromide, and carrying out MOM protection on a phenolic hydroxyl group to obtain a compound 13; the preparation method comprises the following steps: carrying out benzyl bromination on a compound 6, carrying out Negishi coupling reaction on the compound 6 and a compound 13, carrying out 1, 2 addition and Burge reagent elimination, and simultaneously removing an MOM protecting group to obtain the natural product YHB-17. Similarly, the natural product YHB-14 is obtained by using the method. A brand new synthesis strategy is used, reaction repeatability is high, operability is good, and the requirement of large-scale industrial production can be met.

This invention relates to the field of selective hydroxylation technology for aromatic compounds, specifically to a boron-mediated hydroxylation method for 1-phenylpyrazole compounds, comprising the following steps: under the action of boron trihalide, a base, and an oxidizing agent, the 1-phenylpyrazole compound represented by formula (I) undergoes a C-H bond borination reaction with boron trihalide, followed by an oxidation reaction to obtain the compound represented by formula (II); wherein, R 1 and R 2 Individually selected from hydrogen, C1-C6 alkyl groups, phenoxy groups, N,N-dimethyl groups, halogens, thiophene groups, and C6-C6 groups respectively. 14 Any of the aryl groups. This invention does not use any metal catalysis. By coordinating boron tribromide with the directing group pyrazole, the 1-phenylpyrazole substrate first undergoes a C-H bond borylation reaction, and then, under the action of an oxidant, a series of 1-(2-hydroxy)-1H-pyrazole compounds are obtained. This method is efficient, low-cost, and environmentally friendly.

The invention relates to the field of fluorescent carbon nanomaterials, in particular to a high-quantum-yield narrow-band green delayed fluorescence carbon quantum framework and a preparation method and application thereof. The method comprises the following steps: by taking 1-bromo-3-fluorobenzene and boron tribromide as carbon source precursors, adding a reaction catalyst into a carbon source precursor solution, heating a mixed solution, and reacting at 120-150 DEG C for 18-24 hours to obtain a carbon quantum framework solution. The narrow-band delayed fluorescence carbon quantum framework prepared by the invention is formed by bonding four dibenzo [fg, op] tetraene units through a symmetric boron bridge, and has a rigid non-planar conjugated framework structure. The narrow-band delayed fluorescence carbon quantum framework with the quantum yield of 98% prepared by the invention has a wide application prospect in the field of electroluminescence. The compound is applied to an electroluminescent diode, has the advantages of high external quantum efficiency, low efficiency roll-off and the like, and is expected to be used as a low-cost and environment-friendly novel luminescent material to be applied to the field of next-generation display.

This invention relates to a method for preparing a polyester membrane based on perhydroxyl column[5] aromatics. A polyester membrane for dye-salt separation is prepared by interfacial polymerization using perhydroxyl column[5] aromatics as the aqueous monomer. The steps include: (1) synthesizing methoxyl column[5] aromatics from 1,4-dimethoxybenzene and paraformaldehyde under the catalysis of boron trifluoride ether; (2) reacting the purified product with boron tribromide to remove methyl groups and obtain perhydroxyl column[5] aromatics; (3) dissolving the product in an aqueous solution containing triethylamine, and forming a two-phase solution for interfacial polymerization with a hexane solution of trimesoyl chloride; (4) sequentially coating the aqueous solution and organic solution onto the surface of a polyacrylonitrile ultrafiltration membrane, and obtaining the polyester membrane through interfacial polymerization. Based on the inherent cavity and polyhydroxyl characteristics of perhydroxyl column[5] aromatics, compared with traditional polyamide membranes, the obtained polyester membrane has both high permeability and selectivity, and can efficiently separate dyes and inorganic salts, making it suitable for water treatment processes such as dyeing and printing wastewater.

Disclosed is a process for, starting from melatonin, the synthesis of 2-(5-methoxy-lH-indol-3-yl)-N,Ndimethylethan-l-amine (MeO-DMT) or a bufotenin salt, said process involving nucleophilic de-acetylation, contacting the resulting 2-(5-methoxy-lH-indol-3-yl)ethan-l-amine with an aryloxy or alkoxy-carbonylation reagent to form a first carbamate, reducing the carbamate, adding a second aryloxy or alkoxy carbonylation reagent to form a second carbamate and reducing said second carbamate to form MeO-DMT followed by the addition of boron tribromide to MeO-DMT in dichloromethane to form bufotenin hydrobromide.

The invention discloses a kind of two-component aerosol spray paint and preparation method thereof, relate to the field of spray paint.The two-component aerosol spray paint prepared by the present invention, including component A and component B, component A includes modified acrylate copolymer, modified multi-walled carbon nanotube, environmentally friendly solvent, rheological additive, leveling agent, propellant, hydroxy acrylic resin, and component B includes isocyanate curing agent, solvent;Wherein modified acrylate copolymer is by methyl methacrylate, n-butyl acrylate, dimethylallylamine under initiator initiation, obtain acrylate copolymer, then react with chloromethyl (methyl) phosphinoyl chloride, then react with 5-amino-2-chloropyrimidine, then react with 3-methoxy-2-(tributyltin alkyl) pyridine, finally obtained by demethylation of boron tribromide;Modified multi-walled carbon nanotube is by chlorinated multi-walled carbon nanotube grafted chitosan, after sodium periodate oxidation and 2-amino-4,6-di-tert-butylphenol reaction.

The utility model discloses a condensing device which comprises a cooling piece, an air inlet pipe and an air outlet pipe. The cooling piece is provided with a cooling cavity and a liquid collecting cavity, and the cooling cavity and the liquid collecting cavity are independent of each other. The air inlet pipe is partially located in the cooling cavity, the air inlet end of the air inlet pipe is located on the outer side of the cooling piece, and the air outlet end of the air inlet pipe communicates with the liquid collecting cavity. The air outlet pipe is partially located in the cooling cavity, the air inlet end of the air outlet pipe communicates with the liquid collecting cavity, and the air outlet end of the air outlet pipe is located outside the cooling piece. By adopting the condensing device, boron tribromide which is not completely condensed and boron tribromide volatilized in the liquid collecting cavity enter the air outlet pipe, and when the boron tribromide passes through the part, located in the cooling cavity, of the air outlet pipe, the boron tribromide is condensed into liquid and flows back into the liquid collecting cavity. Therefore, volatilization and overflow of boron tribromide can be effectively avoided, and the recovery rate of boron tribromide is improved. The utility model further discloses a high-purity boron preparation system.

The invention discloses two-component aerosol spray paint and a preparation method thereof, and relates to the field of spray paint. The prepared two-component aerosol spray paint comprises a component A and a component B. The component A comprises a modified acrylate copolymer, modified multi-walled carbon nanotubes, an environment-friendly solvent, a rheological additive, a leveling agent, a propellant and hydroxy acrylic resin, and the component B comprises an isocyanate curing agent and a solvent. Wherein the modified acrylate copolymer is prepared by the following steps: initiating methyl methacrylate, n-butyl acrylate and dimethylallylamine by an initiator to obtain an acrylate copolymer, reacting with chloromethyl (methyl) phosphoryl chloride, reacting with 5-amino-2-chloropyrimidine, reacting with 3-methoxy-2-(tributyltin alkyl) pyridine, reacting with 2-chloro-3-(tributyltin alkyl) pyridine, and reacting with 2-chloro-3-(tributyltin alkyl) pyridine to obtain the modified acrylate copolymer. And finally, demethylating through boron tribromide to obtain the product. The modified multi-walled carbon nanotubes are obtained by grafting acylating chlorination multi-walled carbon nanotubes with chitosan, oxidizing the acylating chlorination multi-walled carbon nanotubes with sodium periodate and then reacting the oxidized acylating chlorination multi-walled carbon nanotubes with 2-amino-4, 6-di-tert-butylphenol.

The present invention discloses a method for preparing a water-soluble fluorescent naphthyl[3]arene and its application. The method comprises the following steps: demethylating the naphthyl[3]arene with boron tribromide to obtain a fully hydroxy-substituted naphthyl[3]arene (compound 2); subsequently reacting the compound with tert-butyl bromoalkyl acid to obtain a fully ester-substituted naphthyl[3]arene (compound 3); subsequently hydrolyzing compound 3 with trifluoroacetic acid to obtain a fully carboxylic acid-substituted naphthyl[3]arene; and finally, dissolving the fully sodium carboxylate-substituted naphthyl[3]arene by adjusting the pH. The method prepares a fully sodium carboxylate-substituted naphthyl[3]arene and its application in detecting paraquat. As a supramolecular macrocyclic aromatic hydrocarbon fluorescent probe, the compound has the advantages of simple synthesis, low cost, good selectivity, high sensitivity, and can be used for rapid detection of paraquat and its derivatives in water.

The invention belongs to the technical field of organic compound preparation, and particularly relates to a preparation method of halogenated dibenzofuran. According to the preparation method provided by the invention, methoxy hydroxylation and ring closing steps are completed in one step, the synthetic route of halogenated dibenzofuran is shortened, the method is green and environment-friendly, the synthetic route of direct ring closing of methoxy is widened, the product yield is increased and is 70% or above, generation of impurities is reduced, the purity is 99.96% or above, and the production cost is reduced. According to the method, harmful reagents such as boron tribromide and dichloromethane are not used, three wastes are greatly reduced, and the process safety is improved. The preparation method provided by the invention has good ecological benefits, social benefits and economic benefits, has conditions for industrial large-scale application, and has a wide development prospect.

The invention belongs to the technical field of organic synthesis, and discloses a preparation method and application of a metal-free 1-hydroxycarbazole derivative. The preparation method of the 1-hydroxycarbazole derivative comprises the following steps: (1) mixing a compound I and an organic solvent I, adding sodium hydride under an ice bath condition, heating and mixing, then adding R1COCl, and mixing to obtain a mixture a; (2) removing the organic solvent I in the mixture a, adding an organic solvent II and a dichloromethane solution of boron tribromide into the mixture a in a protective gas atmosphere, and reacting to obtain a mixture b; and (3) removing the organic solvent II in the mixture b, adding sodium perborate tetrahydrate and a potassium carbonate solution into the mixture b, mixing, extracting, drying and concentrating to obtain the 1-hydroxy carbazole derivative. The structural formula of the compound I is shown in the specification; the preparation method is free of transition metal catalysis and low in cost, and the yield of the obtained 1-hydroxycarbazole derivative is high.