23 results about "Boron trifluoride" patented technology

This invention relates to the field of butadiene polymerization technology, and particularly to a butadiene polymerization catalytic system, preparation method, and butadiene polymerization method. The butadiene polymerization catalytic system includes component A, component B, component C, and component D. Component B is an alkylaluminum compound, component C is a boron trifluoride complex, and component D is a homogenizing agent. Component A consists of two parts: component A1 and component A2, wherein component A1 is nickel organophosphate, and component A2 is alkyl nickel acid with a cyclic structure. The preparation process of the catalyst of this invention is simpler, and the product has higher purity, a more defined composition, and a wider and more abundant supply of raw materials, thereby achieving the goals of reducing costs and stabilizing the production process and product quality. Using the technical solution provided by this invention for the production of nickel-based cis-butadiene rubber results in a high polymerization conversion rate of butadiene monomer, good physical and mechanical properties of the product, and low gel content.

This invention relates to an alkyl sulfonyl fluoride resin, its preparation method, and its applications. The structural formula of the alkyl sulfonyl fluoride resin is shown below: where n1 is 1~10000; n2 = 0~2. The preparation method includes: mixing compound 1 as shown in Formula I with a nitrite reagent and boron trifluoride diethyl ether and performing a diazotization reaction to obtain compound 2 as shown in Formula II; and then performing a fluorination reaction of compound 2 with a sulfur source, a fluorine source or a fluorosulfonylating reagent and an acid under the action of a catalyst to obtain the resin. Compared with the prior art, the preparation method of this invention is simple, the raw materials are readily available, and the prepared sulfonyl fluoride resin has high reactivity and good stability, and can be used as a high-efficiency matrix resin for the preparation of novel functional resins.

A collision-resistant pressure vessel steel for storing and transporting boron trifluoride, comprising the following components (wt%): C: 0.10–0.20%, Si: 0.20–0.40%, Mn: 1.25–1.70%, Al: 0.025–0.045%, P≤0.015%, S≤0.005%, V: 0.010–0.025%, Nb: 0.014–0.035%. The process involves: smelting, casting into a billet, heating the billet, rough rolling, finish rolling, cooling, normalizing, and stress relief. The static yield strength Rel of this invention is 350–430 MPa, and the dynamic yield strength Re is 470–675 MPa; the tensile strength is 510–580 MPa; the yield-to-tensile ratio is ≤0.85; and the static elongation after fracture A is 25–41% and the dynamic elongation after fracture A... d The strength-ductility product is 15950–22320 MPa·% at 30–39.1%; the drop hammer tear (DWTT) energy is 17–20 kJ; when the impact velocity is 5–50 m / s and the impact displacement is 1.5 m, the steel plate absorbs 2.70–3.20 kJ of energy, and the ferrite grain size does not exceed 0.029 μm.

The present application belongs to the field of boron trifluoride production, and relates to a method for preparing boron trifluoride and its complex by continuous flow reaction. The method comprises the following steps: uniformly mixing boric acid with concentrated sulfuric acid, then adding oleum or continuously introducing sulfur trioxide gas to obtain an oleum solution of boric acid; introducing the obtained solution and anhydrous hydrogen fluoride gas into a continuous flow reactor at a uniform speed to obtain boron trifluoride gas; purifying and removing impurities from the boron trifluoride gas generated in the reaction; continuously introducing the purified boron trifluoride gas into a complexing solvent for a complexing reaction to obtain a boron trifluoride complex. The method uses a continuous flow reactor to react anhydrous hydrogen fluoride with the oleum solution of boric acid, so that the raw materials can be continuously and uniformly mixed, the reaction is rapid and complete, the process conditions are simplified, the sulfuric acid waste liquid can be recycled after treatment, and the method has economic advantages and process innovation, and is suitable for industrial production.

This invention provides a method for synthesizing 4-methoxypyrrole derivatives, relating to the field of organic chemical intermediate synthesis technology. The 4-methoxypyrrole derivative is prepared by first reacting m-difluorobenzene as a starting material with oxaloyl chloride monoester under Lewis acid catalysis. The reaction product then undergoes cyclization with aminopropionitrile under alkaline conditions. The subsequent product reacts with methanol in a boron trifluoride complex, followed by methylation with a methylating agent under alkaline conditions. This invention overcomes the shortcomings of existing technologies, providing a simple, low-cost, and easily industrialized method for preparing 4-methoxypyrrole derivatives. It offers advantages such as readily available raw materials, high yield, good quality, simple operation, and suitability for industrial production.

The application provides a method for preparing a compound shown in formula I. The method comprises the following steps: contacting a compound shown in formula (II) with a first fluorinating agent to obtain the compound shown in formula (I). The method has low safety risk and low synthesis cost, and is suitable for industrial production. Wherein R1 is F, Cl, Br or I, and the first fluorinating agent is selected from one or more of hydrogen fluoride pyridine, boron trifluoride ether and fluoroboric acid.

The application belongs to the technical field of polymer medical materials, and particularly relates to a four-arm PEG and a preparation method thereof. Specifically, the preparation method comprises the following steps: reacting monomethoxy PEG with bromo-pentaerythritol in an alkaline solvent to form four-arm PEG tetramethyl ether; and then removing the methyl groups from the four-arm PEG tetramethyl ether under the conditions of thiol, boron trifluoride ether and the like for a certain time to generate four-arm PEG. The application can effectively overcome the defects in the existing four-arm PEG preparation method, such as high safety risk and high cost caused by the use of ethylene oxide, and crosslinking products caused by the use of double-end PEG raw materials. The method should use safe and easily available raw materials, and the reaction conditions are mild and controllable, so that the directional high-yield synthesis of four-arm PEG is realized, and therefore the method has good practical application value.

This invention relates to the field of organic synthesis technology, and particularly to a dual-fluorescent probe for Bodipy and NBD, its synthesis method, and its application. The method includes: first, synthesizing NBD coumarin compound 6; then, using nitrobenzaldehyde f and dimethylpyrrole as starting materials, undergoing a four-step one-pot cascade reaction with catalytic amounts of trifluoroacetic acid, DDQ oxidation, and excess triethylamine and Lewis acid boron trifluoride diethyl ether to obtain the fluorescent compound Bodipy h; finally, subjecting the fluorescent compound Bodipy h to reduction and acylation to obtain Bodipy fluorescent probe 8; and finally, after lithium hydroxide demethylation of Bodipy fluorescent probe 8 to obtain a carboxylic acid, which is then amidated with the deBoc-protected NBD compound 6 by trifluoroacetic acid to obtain the target product, dual-fluorescent probe 9. This invention anticipates that the fluorescence of coumarin and naphthalimide, through this dual quenching process, can efficiently achieve the quenching strategy, and can be applied to the simultaneous detection of H2S and hNQO1 in vivo or in vitro.

Disclosed herein are methods for preparing tertiary alcohols from optionally substituted phenyl ketones or optionally substituted pyridyl ketones, the methods comprising the use of chiral ligands and boron trifluoride etherate. The tertiary alcohols can be used to prepare synthetic forms of natural products and / or drugs.

The application discloses an industrialized preparation method of high-purity low-colority boron trifluoride triethanolamine complex and belongs to the technical field of organic boron complex preparation. The application takes triethanolamine and boron trifluoride gas as raw materials, feeds according to a molar ratio of 1:1.02-1.04, and prepares products in a reaction kettle through nitrogen replacement, precooling, three-stage step-by-step aeration complexing, gradient temperature rising degassing and temperature reduction discharging. Through the combined process of sectional temperature control, sectional aeration and gradient degassing, the application solves the problems of local overheating, high colority and high free BF3 content in traditional large-kettle production, and the product has a purity of greater than or equal to 99.0%, a colority of less than or equal to 80 Hazen and free boron trifluoride of less than or equal to 0.2%, and the process is stable and suitable for industrialized large-scale production.

The present application relates to the chemical industry field, specifically to a method for preparing boron trifluoride and its complex from dilute fluorosilicic acid and boric acid. The method comprises the following steps: (1) under heating condition, the dilute fluorosilicic acid reacts with the boric acid to obtain a water solution containing fluoroboric acid and silicon dioxide; (2) the reaction solution of step (1) is cooled, and after cooling, the fluoroboric acid filtrate is collected and the silicon dioxide filter cake is dried; (3) the fluoroboric acid filtrate is extracted with an extractant, the fluoroboric acid enters the oil phase, and the water phase returns to the phosphorite decomposition tail gas absorption system for fluorine absorption; (4) the fluoroboric acid oil phase is distilled under reduced pressure to remove residual water; (5) the fluoroboric acid oil phase from which water is removed is heated, and the fluoroboric acid is decomposed to generate a mixed gas containing boron trifluoride and hydrogen fluoride gas. The method has the advantages of cheap and easily available raw materials, simple process conditions, recyclable extractant, economic advantages and suitability for industrial production.

This invention discloses a centimeter-scale and thermodynamically stable FAPbI3 single crystal, its preparation method, and a pre-derivatization method for molecular-level recognition of the chemical environment of the mother liquor solution. The preparation method includes: uniformly mixing formamidinium hydroiodate, lead iodide, and a single solvent containing a macrocyclic lactone structure compound to form a precursor liquid; forming crystal nuclei in the precursor liquid at a first temperature, and uniformly heating to a second temperature to maintain the cyclic structure of the macrocyclic lactone compound, resulting in centimeter-scale FAPbI3 single crystals; and isothermal treatment at the second temperature to promote ring-opening of the macrocyclic lactone compound to generate long-chain hydroxy acid molecules, resulting in centimeter-scale and stable FAPbI3 single crystals. This invention also provides a pre-derivatization method, using boron trifluoride methanol to perform methyl esterification derivatization on the target molecule, or silanized acetamide derivatization on the target molecule, followed by gas chromatography-mass spectrometry analysis, thereby achieving non-destructive recognition of the target molecule in the mother liquor solution chemistry.

The application discloses a preparation method and application of an aflatoxin M1 hapten and a whole antigen, wherein the hapten contains two complete active carboxyl groups and can be firmly combined with more carrier proteins. The aflatoxin M1 hapten is obtained by addition of aflatoxin M1 and dimercaptosuccinic acid under catalysis of boron trifluoride ether; the whole antigen is a covalent combination of the hapten and BSA, is prepared by using an EDC / NHS carboxyl coupling method, and can be used for antibody preparation and AFM1 detection.

This invention relates to a photocurable composition comprising: cyanoacrylate A selected from the group consisting of n-hexyl cyanoacrylate, n-heptyl cyanoacrylate, n-octyl cyanoacrylate, and mixtures thereof; a free radical photoinitiator; a metallocene compound; compound B selected from the group consisting of boron trifluoride, boron trifluoride diethyl ether, boron trifluoride dihydrate, boron trifluoride ethanol, boron trifluoride methanol, boron trifluoride acetic acid, boron trifluoride butyl ether, boron trifluoride butanol, boron trifluoride propanol, boron trifluoride dimethyl sulfide, boron trifluoride acetonitrile, boron trifluoride tetrahydrofuran, and boron trifluoride isopropanol; and optionally a free radical polymerization inhibitor, provided that when the photocurable composition contains a free radical polymerization inhibitor, its weight content is 0.04 wt.% or less; wherein the molar content of compound B is greater than or equal to 0.141 mmol per 1 kg of composition; and wherein the molar ratio of metallocene compound / compound B ranges from 2 to 8.

This invention discloses a 2-hydroxy-3-pinene-difluoroborane complex-based fluorescent probe for detecting H2S, its preparation method, and its application. The invention uses 2-hydroxy-3-pinene as a raw material and reacts it with 6-hydroxy-2-naphthaldehyde via an aldol condensation reaction to obtain compound DQ; compound DQ undergoes a complexation reaction with boron trifluoride-diethyl ether to obtain compound DQTY; compound DQTY undergoes a substitution reaction with 2,4-dinitrofluorobenzene to obtain the fluorescent probe DQTY-HS. Probe DQTY-HS specifically recognizes H2S. Upon addition of H2S to a DMSO / PBS (1:9, v / v) solution of DQTY-HS, the fluorescence color of the solution changes from colorless to yellow under 365 nm ultraviolet light irradiation, with a response time of 30 s and a detection limit of 50 nM. This probe has many advantages, such as simple synthesis, good selectivity, high sensitivity, good biocompatibility, and low toxicity, and has good application prospects in environmental analysis and food fields.

This invention discloses a method for preparing aflatoxin M1 hapten and full antigen, and their applications. The hapten contains two intact active carboxyl groups, which can firmly bind to more carrier proteins. The aflatoxin M1 hapten is obtained by the addition reaction of aflatoxin M1 with dimercaptosuccinic acid under the catalysis of boron trifluoride diethyl ether. The full antigen is a covalent conjugate of the hapten and BSA, prepared by the EDC / NHS activated carboxyl coupling method, and can be used for antibody preparation and AFM1 detection.