44 results about "Fluroxene" patented technology

The invention discloses a method for synthesizing dendriform compound trifluoroacetate using cage-type octamer (gamma-aminopropyl)silsesquioxane as a core, which comprises the following steps: dissolving OAS hydrochloride and DIPEA (diisopropylethylamine) in DMF (N,N-dimethylformamide), dropwisely adding N,N'-di-tert-butoxycarbonyl-L-lysine N-succinimide ester or N,N'-di-tert-butoxycarbonyl-L-lysine penta-fluorophenol ester dissolved in DMF, and reacting for 10-14 hours; adding -2-2 DEG C acetonitrile, filtering, and drying for 20-24 hours to obtain tert-butoxycarbonyl-protected G1(OL); adding the G1(OL) into -2-2 DEG C trifluoroacetic acid to react for 3-5 hours, adding the reaction mixture into -2-5 DEG C aether, mixing, standing, filtering, and collecting the precipitate, thereby obtaining G1(OL) trifluoroacetate; and adjusting the proportion of the reaction materials, and repeating the rest of steps to obtain G3(OL) trifluoroacetate. The invention has the advantages of low pollution, short reaction time, simple after-treatment and high yield.

The invention provides a method for synthesizing 2,3,4,5,6-pentafluorophenol. The method comprises the steps of (a) carrying out Ullmann reaction on bromopentafluorobenzene as shown in a formula (I) and benzyl alcohol in an inert gas atmosphere under the action of a catalyst cuprous iodide, a ligand and an inorganic base at 100-120 DEG C, and then generating a compound (II), and (b) reacting the compound (II) in an alcoholic solvent in the presence of hydrogen under the action of a palladium carbon catalyst at 20-50 DEG C, and removing the benzyl group, thereby obtaining a compound (III), namely, the 2,3,4,5,6-pentafluorophenol. The method is simple, low in cost and high in yield, and applicable to industrial production. The synthetic route of the method is as shown in specification.

The invention relates to a method for analyzing and detecting trace harmful substances, in particular to a gas chromatography-chromatographic method for determining trace amounts of 3,5-difluorophenol, 5-chloro-2-fluorophenol and 5-bromo-2-fluorophenol in textiles Mass Spectrometry. The steps of the method include enriching the target compound in the textile with a novel adsorbent p-aminobenzenesulfonate-magnesium-aluminum hydrotalcite, using an acid-dissolved adsorbent to achieve complete elution of the target compound, and efficiently extracting the compound with a small dose of organic solvent. After derivatization, it is quickly analyzed and determined by gas chromatography-mass spectrometry. The new adsorbent adopted in this method adopts the method of dispersed solid phase extraction to realize fast and efficient adsorption of the target substance, which has the advantages of fast and high efficiency; the application of acid-dissolved adsorbent can realize the complete desorption of the target substance; only a small amount of organic solvent is used as The extraction solvent of the target object has the characteristics of simple operation steps compared with the conventional phase transfer derivatization method.

The invention relates to a preparation method for pentafluorophenol, and belongs to the technical field of the compound synthesis. The method comprises the following steps: adding Bromopentafluorobenzene to an organic solvent containing magnesium and iodine dropwise to obtain a Grignard reagent; adding the obtained Grignard reagent to the organic solvent solution of borate B(OR)3 in 20-30 DEG C dropwise, and performing the esterification reaction; enabling the obtained cyclopentyl methyl ether solution of the pentaflubenic acid to react with peroxide in 10-50 DEG C, wherein the organic solvent is the cyclopentyl methyl ether or the recycled cyclopentyl methyl ether. The preparation method is capable of using the cyclopentyl methyl ether or the recycled cyclopentyl methyl ether as the reactive solvent, and the solvent is good for the refined recycling. The provided method has the characteristics of easily obtained raw materials, stable technology, convenient operation and high product purity (greater than or equal to 99.5%).

The invention discloses a method for synthesizing 2,3,5,6-tetrafluorophenol, which belongs to the field of fine chemicals. The sterically hindered short-chain fatty acid sodium and pentafluorobenzoic acid are used for reflux reaction in a polar solvent; after the reaction is completed, the strong acid is hydrolyzed and decarboxylated and then steam distilled; the steam distillation product is rectified to obtain 2,3,5,6-tetrafluoroethylene Fluorophenol, the purity is over 99.8%, and the yield is over 88%. The process has the remarkable features of easy operation and little environmental pollution, and has good economic value in preparing 2,3,5,6-tetrafluorophenol products.

The invention discloses quinoxyfen and a synthesis method thereof. The quinoxyfen is prepared from the following raw materials: water, ethyl acrylate, zinc chloride, glacial acetic acid, 3, 5-dichloroaniline, ethanol, sodium hydroxide, toluene, polyphosphoric acid, n-octane, a Pd / C catalyst, dichloroethane, phosphorus oxychloride, p-fluorophenol and N, N-dimethylformamide. The content of the obtained quinoxyfen is greater than 98.0%, and the yield of the obtained quinoxyfen is 50% or above; the production cost is low; in a synthesis process of the quinoxyfen, the processes such as hydrolysis and high-temperature decarboxylation are not needed, so that the operation steps are fewer; the synthesis method is mild in reaction conditions, low in requirements for equipment, better in quality ofproduced products and suitable for large-scale production of enterprises.

The invention discloses a synthesis method of 3,5-difluorophenol, which belongs to the technical field of chemical synthesis. 2,4,6-trifluorobenzoic acid in a solvent, under the action of alkali, obtains 3,5-difluorophenolate through one-pot reaction, and obtains 3,5-difluorophenol after adjusting the acid for free. This method has raw materials It has the advantages of cheap and easy to obtain, short synthesis steps, simple operation, mild reaction conditions, high synthesis yield, good product quality, and suitable for industrial production. 2,4,6-trifluorobenzoic acid uses cheap and easy-to-obtain pentachlorobenzonitrile as a raw material, first undergoes fluorination reaction to obtain 2,4,6-trifluoro-3,5-dichlorobenzonitrile, and then undergoes hydrolysis The reaction obtains 2,4,6-trifluoro-3,5-dichlorobenzoic acid, which is finally synthesized by selective dechlorination reaction, realizing the simple, cheap and efficient preparation of raw material 2,4,6-trifluorobenzoic acid, Improve the industrial application value of the synthesis process.

The invention provides a pentafluorophenol preparation method, which comprises: using hexafluorobenzene and potassium hydroxide as raw materials, adding an appropriate amount of tetrabutylammonium hydrogen sulfate, N-sulfopropyl-3-methylpyridine triflate, N-methyl-2-[(2-methylphenoxy)acetyl]hydrazinium methylthioamide and 2,2,6,6-tetramethylpiperidine-oxynitride to a tert-butyl alcohol aqueous solution with a mass fraction of 80-85%, heating to achieve a slight boiling state, carrying out a reflux reaction for 2-3 h, adding an appropriate amount of water, distilling to recover the tert-butyl alcohol solvent, adjusting the PH value of the remaining aqueous solution by using refined hydrochloric acid to 9-10, adsorbing with a functionalized D101 macroporous adsorption resin, acidifying with refined hydrochloric acid to achieve the PH value of 1-2, layering, distilling the upper layer water phase until no oily substance exists, collecting the distilled product, combining the collected product and the lower layer oil phase, rectifying, collecting the distillate at the temperature of 142-144 DEG C, and cooling to a room temperature to obtain the colorless and transparent crystal pentafluorophenol. According to the present invention, the preparation method has advantages of simple and reasonable process, less side reactions, high reaction yield and high product purity, and can meet the quality requirements for the preparation of the high-quality liquid crystal materials and drugs.

The invention relates to the field of organic synthesis and especially relates to a preparation method for pentafluorophenol. The preparation method comprises the steps of: 1) a Hoffmann rearrangement reaction: performing the rearrangement reaction to the compound (II) in the presence of alkali and a halogenation reagent to prepare the compound (III); 2) a diazo-hydrolysis reaction: performing a diazotization reaction to the compound (III) with a nitroso compound and performing a hydrolysis reaction in the presence of a catalyst to prepare the compound (I). The raw materials in the method are easy to obtain. The preparation method is short in synthesis route and is mild in reaction conditions, is simple in purification of the product, has high product purity and stable product quality, is low in cost of the whole synthesis route and is suitable for industrial large-scale promotion and application.