100 results about "Hydroboration" patented technology

The invention discloses a catalytic system for preparing amine compounds through nitro reduction and application of the catalytic system. The catalytic system comprises an alkaline aqueous solution, a reducing agent and a catalyst, the alkaline aqueous solution is an alkali metal hydroxide aqueous solution; the reducing agent is alkali metal hydroboron and / or alkaline earth metal hydroboron; the catalyst is copper salt lewis acid and / or other lewis acid; the other Lewis acid is selected from one or a combination of more of cobalt salt, ferric salt, zinc salt, manganese salt and palladium salt. When the catalytic system is used for reducing the aromatic nitro-compound, the using amount of a reducing agent is small, meanwhile, the using amount of an organic solvent is reduced, the reaction yield is high, the reaction is milder, and amplified production of the process is facilitated.

The present invention discloses a rapid detection method for sodium polydisulfide (PDPS). The method comprises preparing a buffer solution and an Elma color developer; preparing multiple sets of sodium polydisulfide (PDPS) solutions of different concentrations; pretreating the sodium polydisulfide (PDPS) solutions with an excess of a boron hydride compound as a reducing agent to reduce the sodium polydisulfide to a thiol-containing compound; and removing the excess reducing agent. An absorbance test is performed to establish a standard curve for the concentration and absorbance of the brightener, and the concentration of the sodium polydisulfide (PDPS) in the electrolyte to be tested is measured using the established standard curve. The method uses a boron hydride compound as a reducing agent and utilizes ultraviolet-visible spectroscopy to rapidly detect the content of the brightener, sodium polydisulfide (PDPS). The method is convenient and simple to operate, provides highly accurate test data, and is applicable to the detection of electroplating bath additives in various systems.

The application discloses a catalyst for isocyanate borohydration reaction and a preparation and application method thereof. When the catalyst is used for catalyzing the borohydration reaction of isocyanate and borane to synthesize borate, the catalyst has high catalytic activity, mild reaction conditions (the reaction can be carried out at room temperature), short reaction time, high product yield (≥99%), and the reaction is simple, controllable, and simple in post-treatment.

The present application relates to a kind of catalyst composition and its application in catalytic preparation optically active secondary alcohol, the catalyst composition includes chiral ionic bridged aryloxyalkane rare earth complex and additive, the additive is selected from one or more of pyrimidine, N,N-dicyclohexylmethylamine, 4,4'-dipyridyl.The above-mentioned catalyst composition can be used for synergistically catalyzing asymmetric borohydration of chalcone and its derivatives with pinacol borane, and show high catalytic activity and high enantioselectivity, product yield is as high as 99%, ee value can reach 84%, provide a reliable new way for the efficient, high selective synthesis of optically active secondary alcohol.

A full continuous-flow preparation method of (+)-biotin, including: subjecting a cyclic anhydride and a chiral biphenyl propylene glycol to asymmetric ring-opening reaction to produce a first intermediate, which undergoes selective reduction with a borohydride and cyclization with an inorganic mineral acid to produce (3aS, 6aR)-lactone; subjecting the (3aS, 6aR)-lactone and a sulfenylating reagent to sulfenylation to produce (3aS, 6aR)-thiolactone, which undergoes Fukuyama coupling with a zinc reagent in the presence of a palladium catalyst and elimination reaction in the presence of an inorganic mineral acid to produce an alkenyl valerate compound; subjecting the alkenyl valerate compound to reduction in the presence of a Pd / C catalyst to produce a valerate ester, which undergoes hydrolysis to produce a valeric acid salt; and subjecting the valeric acid salt to debenzylation in the presence of an inorganic mineral acid to produce the target product (+)-biotin.

The invention relates to the technical field of metal organic complexes, in particular to a fluorene-containing alkyl zinc complex and a preparation method and application thereof, and the preparation method comprises the following steps: adding fluorene, potassium tert-butoxide and sodium methoxide into a solvent, and reacting to obtain 9-fluorene formaldehyde; the preparation method comprises the following steps: dissolving 9-fluorene formaldehyde in a solvent, adding an amino compound and a catalyst, and reacting to obtain a formyl fluorene imine ligand; and reacting the formyl fluorene imine ligand with zinc alkyl to obtain the zinc alkyl complex. The invention provides a fluorenyl-containing zinc complex as well as a preparation method and application thereof. The fluorenyl-containing zinc complex is short in reaction route, simple and convenient to operate and capable of efficiently catalyzing an imine hydroboration reaction. Meanwhile, the fluorenyl-containing zinc complex disclosed by the invention is used as a catalyst, is small in usage amount, mild in reaction condition and high in yield, and can catalyze hydroboration reaction of various compounds.

The present invention discloses an octahedral BIF-29 catalytic material and a continuous preparation method and application thereof, which belong to the field of electrochemical catalysis. The octahedral BIF-29 catalytic material includes a metal copper salt and an organic ligand, wherein the organic ligand is tri(1H-imidazolyl) potassium borohydride; the metal copper salt is copper nitrate. The octahedral BIF-29 catalytic material is an M6L8 structure, that is, six metal copper sites are connected to eight organic ligands to form a cage structure, with six exposed mononuclear copper centers, which are connected to the ligands through copper-nitrogen bonds inside, and the micromorphology presents an octahedral morphology. The octahedral BIF-29 catalytic material only needs to be continuously synthesized at a lower temperature and can be used as an efficient electrocatalytic reduction of carbon dioxide catalyst without further treatment. The octahedral BIF-29 catalytic material in the present invention has an electrocatalytic carbon dioxide reduction conversion efficiency of up to 93.7% when participating in the electrocatalytic carbon dioxide reduction reaction.

The application is a kind of continuous preparation method and application of core-shell type reduced Cu-based catalyst. The method uses membrane dispersion micro-reactor technology, adopts liquid phase chemical reduction method with potassium borohydride-hydrazine hydrate as double reducing agent, continuously prepares reduced Cu-based nanoscale catalyst, does not need high temperature calcination and hydrogen reduction, can be directly used as active catalyst for catalytic reaction, and realizes green and efficient preparation. The catalyst prepared by the application is used in the reaction of preparing N-butyl-2,2,6,6-tetramethyl-4-piperidinamine from 2,2,6,6-tetramethyl-4-piperidinone and n-butylamine through reductive amination, and excellent catalytic activity and stability are shown.

The invention belongs to the technical field of hydrogen storage materials, and particularly relates to a metal borohydride composite material, a preparation method thereof and a hydrogen storage material. The preparation method comprises the following steps: activating the carbon-based carrier by adopting an alkaline substance; performing gas-phase fluorination treatment on the activated carbon-based carrier; the carbon fluoride-based carrier is mixed with a metal source, a boron source and a solvent, a solvothermal reaction is driven by hydrogen, metal borohydride is synthesized in situ on the surface of the carbon fluoride-based carrier, metal atoms in the generated metal borohydride react with F atoms in the carbon fluoride-based carrier to form a metal-F bridging phase, and meanwhile, the metal borohydride generates metal vacancies. The metal affinity of fluorine in the carbon fluoride-based carrier is utilized to induce nucleation loading of the metal borohydride in the synthesis process of the metal borohydride, and meanwhile, an interface chemical reaction is carried out to generate vacancies and bridging phases. Vacancies weaken B-H bonds, the hydrogen absorption and desorption heat / dynamics of the material are improved, and the bridging phase improves the structural stability and hydrogen absorption and desorption cycle performance of the material.

The invention discloses p-toluenesulfonic acid 8-tert-butyl diphenyl silyloxy-7-methyl octyl ester as well as a synthesis method and application thereof, and relates to the technical field of biopesticides. The preparation method comprises the following steps: taking 8-bromocaprylic acid as an initial raw material, and firstly reacting with t-BuOK and 18-crown ether-6; then reacting with pivaloyl chloride to generate acid anhydride, and then carrying out acylation reaction with 4-benzyl oxazolidine-2-ketone; then carrying out diastereoselective methylation; then, NaBH4 reduction is carried out; carrying out hydroxyl protection; then carrying out hydroboration oxidation reaction; and then carrying out TsCl sulfonylation, so as to synthesize the p-toluenesulfonic acid-8-tert-butyl diphenyl silyloxy 7-methyl octyl ester. The optical purity of the (S)-p-toluenesulfonic acid 8-tert-butyl diphenyl silyloxy-7-methyl octyl ester synthesized in the invention reaches 98%, and the optical purity of the (R)-p-toluenesulfonic acid 8-tert-butyl diphenyl silyloxy-7-methyl octyl ester synthesized in the invention also reaches 98%.

The invention provides a preparation method of buracametacin hydrochloride and an intermediate compound shown as a formula II thereof. The preparation method of the compound as shown in the formula II comprises the following steps: in the presence of a reducing agent, a compound as shown in the formula I is subjected to a reduction reaction to generate the compound as shown in the formula II. The reducing agent is selected from sodium borohydride and / or lithium borohydride, lewis acid also exists in the reaction system, and the lewis acid is also selected from zinc bromide, zinc chloride, boron trifluoride, aluminum chloride, ferric chloride or a combination thereof. The preparation method disclosed by the invention is low in reducing agent price, mild in reaction, relatively high in product yield and purity, and suitable for industrial large-scale production. # imgabs0 #

The present invention provides a method for preparing an azo borate compound catalyzed by commercially available sodium hydride, belonging to the technical field of green preparation of borate compounds, and capable of solving the urgent problems to be solved in the preparation method of this ester compound. The method includes mixing an azo ester compound with a boron hydride compound, and then adding sodium hydride; the reaction system reacts at 20-80 °C for 6-12 h, and then is exposed to air to terminate the reaction, obtaining the borate compound. The azo ester compound is an aliphatic azo ester compound or an aromatic azo ester compound. The present invention solves the urgent problems such as the high price of the catalyst used in the preparation method of this azo ester compound, the large amount of catalyst used, and the harsh reaction conditions.

The present invention provides a method for preparing natural product dysoxylactam A and its analogues, which relates to the technical field of organic synthesis. The synthetic route starts from aldehydes with different substitutions, constructs four consecutive chiral centers through two aldol condensation reactions, and then through sulfonylation reaction, borohydride reduction, deprotection, protection of hydroxyl protecting groups, and esterification reaction with amino acids, all chiral centers of the target molecule are constructed. Finally, through amide reaction, ring-closing metathesis reaction and hydrogenation reduction reaction, natural product dysoxylactam A and its analogues are successfully obtained. This synthetic method has a high overall yield, simple steps, easy derivatization, low operation requirements, can be prepared in large quantities, and has broad application and development prospects.

The present invention provides a method for preparing an organoborate compound catalyzed by diethylzinc, belonging to the technical field of the preparation of borate compounds, and capable of solving the urgent problems to be solved in the preparation method of this ester compound. The method includes mixing an ester compound with a boron hydride under an inert atmosphere, and then adding diethylzinc; the reaction system reacts at 60-80 °C for 8-12 h, and then is exposed to air to terminate the reaction to obtain the borate compound. The inert atmosphere is nitrogen, and the ester compound is an aliphatic ester compound, an aromatic ester compound, or a cyclic ester compound. The present invention solves the urgent problems such as the complex preparation of the catalyst used in the preparation method of this ester compound, the large amount of the catalyst used, and the long reaction time.

The invention discloses a method for synthesizing alpha-alkenyl boron ester by Markov hydroboration of terminal alkyne, which comprises the following steps of: under the protection of inert gas, carrying out hydroboration reaction on a terminal alkyne compound shown as a formula I and pinacolborane which are used as raw materials and an amide oxazoline cobalt complex which is used as a catalyst in an organic solvent under the action of alkali; the alpha-alkenyl boron ester compound as shown in the formula II is prepared. The invention provides the cobalt complex catalyst with high efficiency, high selectivity and high substrate compatibility and the method, the reaction condition is mild, the operation is simple and convenient, the atom economy is high, and the product yield and the selectivity of the product are improved. When the catalyst is used for a gram-level amplification reaction, a crude product can be purified in a recrystallization or distillation manner, so that the purification step is greatly simplified, and the technical problems of difficulty in separation and low yield in a reaction amplification process of synthesizing alpha-alkenyl boron ester by Markov hydroboration of terminal alkyne in the prior art are solved; and the method has a relatively high industrial application value.

The invention provides a copper-based high-entropy alloy material and a preparation method and application thereof.The copper-based high-entropy alloy material comprises Cu, Lu, Yb, Tm, Er and Ho, CuLuYbTmErHo-LDHs (layered double hydroxides) are prepared from cheap metal nitrate and a sodium hydroxide solution through a coprecipitation method, the CuLuYbTmErHo-LDHs (layered double hydroxides) are dried and ground into powder, thermal reduction is conducted in the atmosphere of hydrogen and nitrogen, and the copper-based high-entropy alloy material is obtained. The copper-based high-entropy alloy material is obtained; the copper-based high-entropy alloy material provided by the invention is used as a catalyst for an alkyne hydroboration reaction, the catalytic reaction condition is mild, no additive is needed, the reaction universality is good, the reaction yield is relatively high, the atom economy is high, the substrate universality is wide, the catalyst is easy to recover, the activity is not obviously reduced after the catalyst is recycled for more than 6 times, and the method is suitable for industrial production. The method has a potential large-scale application prospect.

The invention belongs to the technical field of preparation of catalytic materials, and provides a high-density defective polyacid-based metal organic framework catalyst for hydroboration, a preparation method and application. According to the catalyst, a metal organic framework with defects is constructed by adopting a mixed ligand strategy, a polyacid cluster is introduced in situ on the basis of the metal organic framework, and through weak interaction between a cluster object and a subject framework, regulation and control of an oxidation state of a metal node and regulation and control of a supporting effect of an expanded pore space are realized at the same time; therefore, the problem of unstable structure caused by high defect content is overcome, the polyacid-based metal organic framework catalyst with high-density defects is successfully constructed, the catalyst solves the problems that the existing hydroboration reaction is high in temperature, the catalyst is difficult to recycle and the like, efficient conversion of the alkyne hydroboration reaction can be realized, and the yield of the alkyne hydroboration reaction is increased. Moreover, the structure is still stable after repeated cyclic utilization and use, and can be expanded to various alkyne substrates.

The invention discloses high-purity lithium borohydride and a preparation method thereof, and belongs to the technical field of inorganic synthesis.The preparation method comprises the steps that firstly, surface coordination activation is conducted on micron-sized lithium hydride through amino silane, and the reaction activity of the micron-sized lithium hydride is remarkably improved; and then, in a uniform ionic liquid organic solvent composite medium, efficiently synthesizing lithium borohydride with a purified borane complex at a mild temperature. For key impurity chloride ions, trimethylchlorosilane is innovatively introduced to carry out targeted precipitation conversion, and effective removal is carried out before crystallization. And finally, directly separating out a high-purity product from a reaction system through a directional crystallization technology. According to the high-purity lithium borohydride and the preparation method thereof disclosed by the invention, high-efficiency preparation of high-purity and low-chloride-ion lithium borohydride under a mild condition is realized, a key reagent can be recycled, and the problems of high energy consumption and insufficient purity in a traditional method are perfectly solved.

The invention discloses a heat-resistant bio-based degradable polyester material and a preparation method of the heat-resistant bio-based degradable polyester material, and belongs to the field of bio-based high polymer materials. Two brand-new bio-based modified compounds are introduced, wherein one compound is diol with a bicyclic structure prepared by reacting bio-based vanillin with epichlorohydrin and carrying out hydroboration-oxidation, and the other compound is binary acid with an imidazole ring generated by hydrogenating bio-based itaconic acid and condensing the hydrogenated bio-based itaconic acid with ethylenediamine. The preparation method comprises the following steps: melting and mixing 1, 4-butanediol, adipic acid and two modified compounds, adding a catalyst and a nucleating agent, carrying out condensation polymerization under a high-temperature vacuum condition, and drying to obtain the polyester material. According to the material, the heat resistance is synergistically improved through the rigidity of a double-ring structure and the polarity of an imidazole ring, and the material is clear in bio-based source, can be completely biodegraded and is suitable for the fields of high-temperature packaging, degradable meal boxes and the like.

The invention relates to a catalytic system based on at least one neodymocene borohydride, a co-catalyst which is a dialkylmagnesium compound of formula RB-Mg-RL, in which RB is a secondary alkyl of formula R2CH and RL is a primary alkyl of formula RCH2, the Rs, identical or different, being alkyls. The catalytic system addresses the objective of improved macrostructure control in a polymerization process of ethylene or a monomer mixture containing ethylene and a 1,3-diene.

The present invention discloses a 1,4,7,10-tetraazadodecane derivative, a preparation method, and its use in the synthesis of gadolinium complexes, belonging to the field of organic synthesis. The method uses compound 1 as a substrate and reacts it with lithium borohydride to produce compound 2. By utilizing a specific selective reduction reaction route and specific intermediates, this method eliminates the need for overprotection / deprotection steps, reduces reaction steps, and improves preparation efficiency.

The invention belongs to the technical field of organic synthesis, and particularly discloses a synthesis method of isopinopinone, which comprises the following steps: (1) by taking alpha-pinene as a raw material, hydroborating by using a borane tetrahydrofuran complex, and oxidizing the hydroboration product by using a sodium hydroxide solution and hydrogen peroxide to obtain isopinopinol; (2) performing high-temperature dehydrogenation on the isopinopinol by taking Cu / Ni-Al-SBA-15 as a catalyst to obtain a product, namely isopinopinone; the total loading capacity of Cu and Ni in the Cu / Ni-Al-SBA-15 is 9-12%, the molar ratio of Cu to Ni is (8-10): 1, and the molar ratio of Si to Al in the carrier Al-SBA-15 is (9-11): 1. The conversion rate and the yield of the two-step reaction are relatively high, the dehydrogenation catalyst in the second step can be recycled for more than three times through filtration, and compared with a traditional copper-silicon catalyst, the mesoporous weak-acid molecular sieve serving as a carrier can effectively improve the product selectivity. The purity of the isopinopinone obtained through filtration and rectification can reach 99% or above, the cost can be effectively reduced, and industrial production can be achieved.

The present invention discloses a fully continuous flow preparation method for (+)-biotin. The method comprises: performing an asymmetric ring-opening reaction on a cyclic anhydride and a biphenyl chiral propylene glycol, performing a selective reduction reaction on the product with a borohydride, and then performing a cyclization reaction with an inorganic mineral acid to obtain (3a S ,6a R ) lactone; (3a S ,6a R ) The lactone undergoes a thiolation reaction with a thio reagent, the product then undergoes a Fukuyama coupling reaction with a zinc reagent in the presence of a palladium catalyst, the product undergoes an elimination reaction in the presence of an inorganic mineral acid to obtain an alkenyl valerate compound; the alkenyl valerate compound is reduced in the presence of a palladium / carbon catalyst to obtain a valerate ester; a hydrolysis reaction is performed to obtain a valerate salt; and the valerate salt undergoes a debenzylation reaction in the presence of an inorganic mineral acid. The process of the present invention is carried out continuously, the total time is greatly shortened, the total yield is increased to 48.7%, the degree of automation is high, the time-space yield is high, and the method is suitable for industrial production.

The invention belongs to the technical field of organic synthesis, and particularly relates to a branched perfluoropolyether phosphate compound, a composition as well as a preparation method and application of the branched perfluoropolyether phosphate compound. According to the invention, perfluoropolyether alcohol is used as a raw material, and is subjected to substitution, hydroboration and other reactions to prepare the branched perfluoropolyether phosphate compound. The obtained compound has a multi-branched perfluoropolyether chain, after curing, the multi-branched perfluoropolyether group is dissociated on the surface of a metal base material to form a compact perfluoropolyether film layer, excellent hydrophobic and oleophobic properties and smoothness can be provided, in addition, the multi-branched perfluoropolyether is also beneficial to faster energy conversion or release when the compound is stressed, and the performance of the compound is improved. Further, the friction resistance of the coating is favorably improved. Lone pair electrons contained in phosphorus and oxygen heteroatoms in a phosphate group at the tail end of a molecule can be subjected to characteristic adsorption with empty orbits of atoms on the surface of a metal base material, meanwhile, hydroxyl at the tail end of the molecule can also be combined with hydroxyl on the surface of the base material to form hydrogen bonds to be firmly combined with the base material, a compact phosphate protective film is formed, and good protection performance is achieved.

The invention discloses a preparation method of a nucleotide monomer, which comprises the following steps: taking methyl-D-ribofuranoside as an initial raw material, and finally realizing the synthesis of a compound monomer as shown in a formula P through the steps of selective protection, selective deprotection, C-C bond construction, acylating chlorination reaction, basic group introduction through glycosylation, deprotection, hydroboration oxidation and ring closing in sequence. By providing a brand new synthesis method, the reaction yield is improved, the cost of the whole synthesis molecule is reduced, the binding affinity of the prepared target nucleoside monomer serving as a reported drug applied to HCV resistance to RNA can be improved so as to further improve nuclease resistance, and the method has great significance for subsequent nucleic acid drug research.

The invention belongs to the field of total synthesis of natural products, and relates to an asymmetric total synthesis method of a natural product (-)-Lucidutone. The total synthesis of the natural product takes known compounds S1 and S2 as synthesis starting points, and a basic skeleton of (-)-Lucidutone is constructed through key reactions such as key Lewis acid catalyzed intramolecular Diels-Alder, hydroboration oxidation, Suzuki coupling, acid catalyzed deprotection / Prins reaction / cyclic etherification series connection and the like. The asymmetric total synthesis method of the (-)-Lucidumone is successfully invented at a relatively high total yield by carrying out a series of functional group conversion such as Fleming-Tamao oxidation, Grieco elimination and Wacker oxidation on the (-)-Lucidumone and then carrying out a series of functional group conversion such as the Fleming-Tamao oxidation, the Grieco elimination and the Wacker oxidation. The synthesis method is relatively simple to operate, can be widely popularized and used, and lays a solid foundation # imgabs0 # for deeper pharmacological and physiological activity research of (-)-Lucidutone

The invention belongs to the technical field of molecular sieve preparation, and provides a boron-doped MFI type hierarchical pore molecular sieve and a preparation method thereof. The preparation method comprises the following steps: mixing an organic template agent solution, a silicon source and a boron source to obtain reaction precursor gel; and sequentially carrying out hydrothermal crystallization and roasting on the reaction precursor gel to obtain the boron-doped MFI type hierarchical pore molecular sieve, the boron source is hydroboron. According to the method, borate released by slow hydrolysis of hydroboron is used as a boron source, hydrogen released in the hydrolysis process is used as a soft template, modulation of the pore channel structure of the molecular sieve is realized, and the molecular sieve with a micro-mesoporous structure is constructed, so that the mass transfer efficiency of the MFI type molecular sieve is improved, and limitation of steric hindrance and diffusion resistance is reduced.

The invention discloses a mono-nickelocene complex containing dithioformate, and the mono-nickelocene complex containing dithioformate has a structure as shown in the following formula: in the formula, substituent groups R are N (C2H5) 2, NH (C6H11) and OC2H5. The invention discloses a preparation method of the mono-nickelocene complex containing dithioformate, which comprises the following steps: dissolving a disulfide ligand and [Ni2 (C5H5) 3] BF4 in dichloromethane and methanol, reacting in an inert atmosphere, and separating and purifying to obtain the mono-nickelocene complex containing dithioformate. The invention discloses application of the mono-metallocene nickel complex containing dithioformate in catalyzing hydroboration reduction of aldehyde compounds to obtain organic boric acid ester compounds. The mono-nickelocene complex containing dithioformate provided by the invention is novel in structure and simple in preparation process, can efficiently and selectively catalyze the hydroboration reduction reaction of an aldehyde compound under mild conditions to prepare an organic borate compound, and has wide application prospects.

The invention relates to the field of synthesis of organic compounds, in particular to a hydroboration reaction method for catalyzing ketone by a rare earth metal complex. The method for catalyzing the hydroboration reaction of the ketone by the rare earth metal complex comprises the following steps: mixing the rare earth metal complex, pinacolborane, the ketone and a solvent in an inert atmosphere, and reacting, the general chemical formula of the rare earth metal complex is RE (OTf) 3, and RE is a rare earth element. According to the method for catalyzing the hydroboration reaction of the ketone by using the trifluoromethanesulfonic acid rare earth metal (RE (OTf) 3), the catalyst is a commercial product and is low in price, simple and convenient to operate, high in reaction activity, wide in substrate range and high in yield.