28 results about "Grignard reagent" patented technology

This invention provides a method for preparing Centhaquine, a drug for treating hemorrhagic shock. Specifically, the preparation method provided by this invention includes the following steps: (S1) providing compound II and compound IV; wherein compound II is prepared by the following method, which includes the steps of: (A) reacting compound I with 1,2-dibromoethane in a first solvent in the presence of base 1 to obtain compound II; and compound IV is prepared by the following method, which includes the steps of: (B) reacting compound III with pinacol diborate in a second solvent in the presence of Grignard reagent to obtain compound IV; (S2) preparation of compound A; and reacting compound II and compound IV in a third solvent in the presence of a catalyst and base 2 to obtain Centhaquine. The preparation method of this invention has a simple and safe synthetic route and operation, readily available raw materials, simple post-processing, high yield, and is suitable for industrial production.

This invention relates to the field of organic synthesis technology, specifically to a highly efficient and stable Grignard preparation and its green preparation method. By weight, it comprises 8-18 parts of a magnesium source, 40-92 parts of a halogenated hydrocarbon, 150-200 parts of a green solvent, 15-20 parts of ethylene glycol dimethyl ether, and 2.3-3.2 parts of a synergistic stabilizer. The green solvent is 2-methyltetrahydrofuran, or a composite solvent with a weight ratio of 2-methyltetrahydrofuran:methyl tert-butyl ether of 150-160:40-50. The synergistic stabilizer is composed of 1.5-2.0 parts of N,N,N',N'-tetramethylethylenediamine and 0.8-1.2 parts of butylated hydroxytoluene, or composed of 1.5-2.0 parts of N,N,N',N'-tetramethylethylenediamine and 1.0 part of phenothiazine. This invention uses a green solvent system to replace traditional toxic and harmful solvents, and combines it with a solvent recovery process to achieve solvent recycling, which greatly reduces waste emissions and makes the production process safer and more environmentally friendly, in line with the development direction of green chemical industry.

Methods for forming a vapor deposition precursor are provided. The method comprises contacting an aluminum halide compound, an alkoxy aluminum compound, and a Grignard reagent to form the vapor deposition precursor. The vapor deposition precursor comprises an dialkyl aluminum alkoxide compound. The vapor deposition precursor is formed without use of a pyrophoric compound. Related compositions, related precursors, and related methods are also provided, among other things.

The application provides a preparation method of dihydroxy boron phenylalanine and intermediates thereof. The method comprises the following steps: mixing 4-halogen-Boc-L-phenylalanine of formula (II) with an alkyl borate, and adding a Grignard reagent to obtain an intermediate compound of formula (I): (I) (II).

This invention discloses a chiral monophosphine ligand, its preparation method, and its application in asymmetric synthesis. The ligand preparation method involves mixing an N,N',1,2-tetrasubstituted ethane-1,2-diamine compound, phosphorus trichloride, triethylamine, and solvent under a nitrogen or argon atmosphere at -80 to -70°C, and reacting at 60 to 80°C for 6 to 8 hours. The resulting reaction mixture is then cooled to room temperature, and an alcohol, phenol, or Grignard reagent is added dropwise, reacting at 60 to 80°C for 8 to 12 hours. The resulting mixture is then post-treated to obtain the chiral monophosphine ligand. The application involves stirring a nickel catalyst, a chiral monophosphine ligand, a solvent, a diene, and an aldehyde under an argon or nitrogen atmosphere at a specified temperature for 12 to 15 hours. The mixture is then post-treated to obtain the target product. This method utilizes widely available and inexpensive raw materials, and the operation is simple, achieving high stereoselectivity and enantioselectivity in the synthesis of alcohol compounds containing chiral conjugated dienes through a one-step reaction.

The application discloses a flocculant for concrete mixture water-washed sand and a preparation method thereof. The flocculant is in a spherical configuration and is composed of a polystyrene inner core and a large number of polyacrylamide coating layers grafted on the surface of the polystyrene inner core. The preparation method comprises the following steps: firstly, preparing a styrene / hydroxyethyl acrylate / methoxy-terminated polyethylene glycol alkene copolymer P through free radical polymerization; then, performing ring-opening polymerization on the copolymer P by taking alpha-halogen-gamma-lactone as a polymerization monomer under the action of an organic metal catalyst to obtain a grafted poly(alpha-halogen-gamma-lactone) polymer S; then, adding magnesium powder to prepare a Grignard reagent polymer S-Mg-X; then, introducing carbon dioxide and hydrogen to prepare a carboxylic acid polymer S-COOH; then, filtering and removing magnesium carbonate precipitate; and finally, adding ammonia to perform amidation reaction to prepare the flocculant. The machine-made sand prepared by using the flocculant for concrete mixture water-washed sand has excellent initial plasticizing performance and good plasticizing retention capacity.

This invention discloses a method for preparing tetraenestrol, comprising the following steps: S1. Etherification reaction: In a solvent and in the presence of a catalyst, compound I is etherified with methanol to generate compound II, yielding a solution of compound II; S2. Grignard reaction: The solution of compound II obtained in S1 is reacted with a Grignard reagent to generate compound III, yielding a solution of compound III; S3. Hydrolysis reaction: In the presence of an acid, the solution of compound III obtained in S2 is hydrolyzed to generate compound IV, yielding a solution of compound IV; S4. Dehydrogenation reaction: In the presence of a dehydrogenation reagent, the solution of compound IV obtained in S3 is dehydrogenated to generate compound V, yielding tetraenestrol. This preparation route features simple reaction operation, high overall yield, and high product purity, reducing the overall production cost.

This disclosure provides a process for preparing α-hydroxy esters by adding a vinyl Grignard reagent to an oxalate ester and then thiolated the resulting double bond. It also provides α-hydroxy esters and synthetic intermediates prepared according to the process disclosed herein, as well as compositions comprising said α-hydroxy esters.

The application discloses an olefin-based tertiary amine monomer for a crosslinked anion exchange membrane and a preparation method and application thereof. The monomer structure is shown in a general formula: (R a)(R b)N-R c, wherein R a and R b are each independently selected from an alkyl group, an aryl group, a heterocyclic group or an alkenyl group, R c is a group containing at least one alkenyl group, and at least two groups of R a, R b and R c each contain at least one alkenyl group. The preparation method comprises the following steps: halogenating a tertiary alcohol amine to obtain a halogenated tertiary amine, and then reacting the halogenated tertiary amine with a Grignard reagent prepared from a halogenated olefin to obtain the target monomer. The monomer contains multiple alkenyl groups and tertiary amine groups in the molecule, can be used as a precursor with polymerizable and ionizable functions, and is used for preparing an anion exchange membrane with a three-dimensional network crosslinked structure. The raw material is easy to obtain, the synthesis route is simple, the product structure is adjustable, the prepared anion exchange membrane has high ionic conductivity, excellent dimensional stability and alkali resistance, and is suitable for alkaline fuel cells, water electrolysis hydrogen production and other electrochemical devices.

Methods for forming a vapor deposition precursor are provided. The method comprises contacting an aluminum halide compound, an alkoxy aluminum compound, and a Grignard reagent to form the vapor deposition precursor. The vapor deposition precursor comprises an dialkyl aluminum alkoxide compound. The vapor deposition precursor is formed without use of a pyrophoric compound. Related compositions, related precursors, and related methods are also provided, among other things.

This invention discloses a silicon-containing monophosphine ligand, its preparation method, catalytic composition, and applications, belonging to the field of organic synthesis and catalysis technology. Addressing the problems of existing cobalt-based olefin hydroformylation systems, such as difficulty in effectively controlling the ratio of n-alcohol to iso-alcohol in the products, limited freedom in ligand structure design, and insufficient system stability and scale-up applicability, the silicon-containing monophosphine ligand of this invention can be prepared by coupling a Grignard reagent with a phosphine chloride. Furthermore, the cobalt-phosphine catalytic system composed of the silicon-containing monophosphine ligand and a cobalt precursor can achieve the direct conversion of various olefins to their corresponding alcohols under a CO / H2 atmosphere. By adjusting the structural parameters of the ligand, the ratio of n-alcohol to iso-alcohol in the products can be effectively controlled. This catalytic system exhibits good thermal stability and applicability during the reaction process, making it suitable for the industrial application of one-step preparation of higher alcohols from various olefins.

This invention belongs to the field of organic synthesis technology, specifically relating to a method for preparing racemic nicotine and a method for resolving levorotatory nicotine. The method for preparing racemic nicotine includes the following steps: First, a Grignard reagent is prepared using 3-bromopyridine and magnesium as raw materials; then, N-methylpyrrolidone is added to the Grignard reagent for a condensation reaction. After the reaction, an enamine intermediate is obtained, followed by the addition of an acid to obtain an ammonium salt; finally, the obtained ammonium salt is reacted under the action of a reducing agent to prepare racemic nicotine. Levorotatory nicotine is obtained by resolving and recrystallizing racemic nicotine with L-(-)-dibenzoyl tartaric acid in a mixed solvent of methanol and isopropanol through two stages. The method for preparing racemic nicotine using this invention uses inexpensive starting materials, has mild reaction conditions, and yields a high product yield. Furthermore, the method for resolving levorotatory nicotine in this invention involves fewer chiral resolution steps, achieves good resolution, and is suitable for industrial-scale production.

This invention discloses a silicon carbide fiber precursor polycarbosilane and its preparation method, belonging to the field of polycarbosilane preparation technology. The preparation method of the silicon carbide fiber precursor polycarbosilane includes the following steps: Step 1: Preparing a Grignard reagent; Step 2: Adding an organic alkane to tetrahydrofuran, stirring and mixing, then slowly adding it to the Grignard reagent, stirring and reacting; after the reaction is complete, heating to room temperature, adding a composite organic auxiliary agent, stirring and reacting; after the reaction is complete, quenching the reaction, separating the liquids, washing, and drying to obtain a prepolymer; Step 3: After vacuum distillation of the prepolymer, transferring it to a reaction vessel, heating and polymerizing it under argon atmosphere; after the reaction is complete, adding it to toluene, dissolving, filtering, precipitating, and drying to obtain the silicon carbide fiber precursor polycarbosilane. The polycarbosilane prepared by the above method has excellent thermal stability and high-temperature mechanical properties.

The application discloses a method for preparing L-selenium-methyl selenocysteine by organic phosphine reduction, which is prepared by one-pot method under the reduction of organic phosphine, taking L-serine or L-serine derivative as raw material and dimethyl diselenide as selenium source. Compared with the conventional chemical synthesis method, the method for preparing L-selenium-methyl selenocysteine by organic phosphine reduction can efficiently synthesize L-selenium-methyl selenocysteine and its derivative under the reduction of organic phosphine, can obtain L-selenium-methyl selenocysteine with high yield and high purity, has the advantages of simple synthesis route, no need to use boron hydride reducing agent or Grignard reagent with explosion hazard, mild reaction condition, safe and reliable process, cheap and easily available raw material, high product yield, high purity and the like, and has important promoting effect on realizing large-scale industrial application of L-selenium-methyl selenocysteine.

The application belongs to the technical field of organic synthesis chemistry, and particularly relates to a fluorine-containing hydroxybenzoic acid compound and a preparation method. The application provides a novel synthesis path, which takes 4-fluoro-3-methoxybenzonitrile as a starting material, firstly performs specific demethylation reaction in benzene or toluene solvent through anhydrous aluminum chloride catalysis to obtain an intermediate 4-fluoro-3-hydroxybenzonitrile; then performs acid hydrolysis reaction on the intermediate in a mixed medium of concentrated sulfuric acid and water to convert the cyano group into a carboxyl group, and obtains 3-hydroxy-4-fluorobenzoic acid crude product; finally, high-purity product is obtained through directional recrystallization of an ethanol-water mixed solvent. The application fundamentally avoids competitive bromination and Grignard reagent application of a traditional route, and has the remarkable advantages of simple route, mild condition, safe operation, high selectivity, environmental friendliness and easy industrial implementation.

The present application relates to a kind of heat-insulating materials and its application in intermediate synthesis finished product crystallization reactor, belong to heat-insulating material technical field;The present application is obtained 4-chloro-1-butene-3-al by the ring opening of ethylene oxide with dilute hydrochloric acid, then with p-toluenesulfonyl chloride to obtain sulfonate derivative, then with magnesium scrap to generate grignard reagent, then with tetraethyl orthosilicate to obtain sulfonate silane;Then sulfonate silane and sodium azide carry out azide reaction to obtain azidosilane, and azidosilane and triphenylphosphine are reacted to obtain amino co precursor;Amino co precursor is mixed with tetraethyl orthosilicate, anhydrous ethanol and deionized water, and hydrophobic aminosilica aerogel is prepared by aging and drying;Finally, with polyether polyol as base material, add hydrophobic aminosilica aerogel, then with diphenylmethane diisocyanate to obtain heat-insulating material.

This invention discloses a method for preparing asymmetric diphenyl sulfide compounds. Disubstituted phenyl disulfide and lithium chloride-containing substituted phenyl magnesium halide (Knochel-type Grignard reagent) are dissolved in an organic solvent, and the reaction is stirred at room temperature while the reaction progress is monitored using gas chromatography. After approximately 2 hours, the reaction proceeds completely. The reaction solution is extracted with ethyl acetate, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to obtain a crude product. Subsequently, the crude product is purified by column chromatography to obtain the desired asymmetric diphenyl sulfide compounds. This method uses disubstituted phenyl disulfide and lithium chloride-containing substituted phenyl magnesium halide (Knochel-type Grignard reagent) as starting materials to synthesize asymmetric diphenyl sulfide compounds. The synthetic route is simple, requires no external transition metal catalyst, exhibits good functional group tolerance, can be scaled up, and is easy for industrial production.

This utility model discloses a metering and feeding device for anhydrous and oxygen-free reactions in industrial scale-up production, relating to the technical field of chemical reaction apparatus for industrial scale-up production. The device includes a reaction vessel unit, comprising a vessel body and a thermometer and pressure gauge mounted on the vessel body; a condensation and reflux unit connected to the vessel body for condensing and refluxing steam within the vessel body; a material feeding unit connected to the vessel body for adding materials into the vessel body; and a gas drying unit, whose inlet is connected to a gas source and whose outlet is connected to both the material feeding unit and the vessel body, wherein the gas source is nitrogen or an inert gas. The device provided by this utility model is easy to connect and maintain, and has good sealing performance; the entire system ensures that the reaction takes place in an anhydrous and oxygen-free environment, and is suitable for feeding reactions of Grignard reagents, LDA, and the active metal compound n-butyllithium in scale-up production.

The present invention relates to a method for preparing an organometallic compound for a vapor deposition precursor with high yield, the method comprising the steps of: reacting a compound containing a halogen element with a Grignard reagent; and reacting a substituted or unsubstituted aromatic ring.

This invention discloses a triarylborane, its preparation method, and its applications. The triarylborane of this invention has the structural formula shown in Formula II. The preparation method of the compound shown in Formula II includes the following steps: In an inert atmosphere, a solution of bromoaromatic or iodoaromatic hydrocarbons in diethyl ether is stirred and a solution of isopropyl magnesium chloride in diethyl ether is added dropwise; after the addition is complete, the reaction is continued with stirring to obtain a mixed solution; in an inert atmosphere, the mixed solution is mixed and reacted with a suspension of the compound shown in Formula I of claim 1 in diethyl ether; the solvent is removed from the mixture, the residue is dissolved in toluene, and trimethylchlorosilane is added and the reaction is stirred to obtain the compound shown in Formula II, which is the triarylborane. This invention uses Grignard reagents prepared in situ from different diaryl difluoroborate potassium and haloaromatic hydrocarbons to flexibly synthesize a series of triarylboranes with different functional groups, characterized by the fact that the three aryl substituents are all different.

This invention discloses a method for synthesizing chiral δ-caprolactam compounds. Using N-Boc-L-pyroglutamate as a starting material, intermediate II is obtained through nucleophilic ring-opening with a Grignard reagent. This intermediate is then subjected to enamidation of a ketone and cyclization with a lactam to form intermediate III. Halogenation of intermediate III yields intermediate IV, which is then coupled with a metal-catalyzed reaction to obtain intermediate V. By controlling the chirality at the C-3 position of intermediate V and catalytically reducing the C5-C6 carbon-carbon double bond, chiral intermediate VI is obtained. Intermediate VI undergoes trifluoroethylation and crystallization-induced diastereomeric transformation to prepare the key aminolactam intermediate A for the drug ubrogepant. This invention avoids the chiral resolution by high-performance liquid chromatography, the high technical barriers of transaminase catalysis, and the cumbersome salt-forming resolution process, thus improving the synthetic efficiency of chiral δ-caprolactam compounds and possessing significant industrial application value.

The application discloses a synthesis method of quinolinic acid, which comprises the following steps: (1) using a halogenated pyridine derivative as raw material, performing a Grignard reaction with a Grignard reagent solution to generate a first intermediate; (2) performing a carbonylation reaction on the first intermediate with carbon dioxide to obtain a second intermediate; and (3) performing an oxidation reaction on the second intermediate with an oxidizing agent to obtain a product quinolinic acid, and the specific reaction is shown in the following formula, wherein X is halogen, R is C 1‑3 alkyl or cyano, and R1 is C 2‑4 alkyl. The application provides a new method for preparing 2,3-pyridinedicarboxylic acid (quinolinic acid), which uses a halogenated and alkyl-substituted or cyano-substituted pyridine derivative as raw material, performs a Grignard reaction with a Grignard reagent, then performs a carbonylation reaction with carbon dioxide, and finally performs hydrolysis to obtain the product 2,3-pyridinedicarboxylic acid (quinolinic acid). The synthesis route has the advantages of mild reaction, easy operation, safety and environmental protection, and convenience for large-scale production.

This invention discloses a method for preparing 4,4'-bis[cyclo[4.2.0]octyl-1(6),2,4-trien-3-ylmethyl]-1,1'-biphenyl, belonging to the field of chemical synthesis. The method uses 4-bromobenzocyclobutene and 4,4'-biphenyldicarboxaldehyde as raw materials, and completes the process in five steps: Grignardization, coupling, solvent replacement quenching with glacial acetic acid, reduction, and purification. The Grignardization reaction uses a cyclic ether as a solvent and is carried out at 45-60℃ to prepare an aryl Grignard reagent; the coupling reaction is carried out at ≤35℃ to achieve nucleophilic addition of the aryl group to the aldehyde group; after quenching with glacial acetic acid and removing the low-boiling solvent, reduction is completed with iodine granules and hypophosphite at 55-62℃; finally, the target product is obtained by dry loading with silica gel at ≤40℃ and column chromatography in a weakly polar system. The process of this invention is simple and mild, with a completely anhydrous and oxygen-free controllable process. The product has a purity of ≥99%, excellent yield, and is suitable for large-scale production. The obtained product can be used as a monomer for photoelectric anti-corrosion dry film polymer.