343 results about "Enantio selectivity" patented technology

The invention relates to the technical field of biochemical engineering, in particular to a method for preparing chiral alpha-trifluoromethyl alcohol by using imine reductase AtRedAm, trifluoromethyl ketone is reduced into corresponding chiral trifluoromethyl alcohol at an excellent conversion rate by using the imine reductase AtRedAm, and enantioselectivity is high. The reaction depends on an NADPH (Nicotinamide Adenine Dinucleotide Phosphate) coenzyme circulation system, 10% dimethyl sulfoxide is used as a reaction cosolvent, the reaction is carried out in a 100mM (pH = 7.5) phosphate buffer solution for 16 hours, the highest molar conversion rate reaches 99%, and the highest optical purity reaches 95%.

The invention provides a novel chiral ferrocene bridged binaphthyl skeleton phosphine ligand and application thereof. The ligand has the advantages of low cost, simplicity in synthesis, air stability and the like. The ligands have good catalytic activity and enantioselectivity in the asymmetric hydrogenation reaction of ketone, and have certain industrial application prospects in the synthesis of pharmaceutical molecules.

The invention discloses a p-nitrophenyl ethyl esterase mutant with high enantioselectivity as well as a construction method and application of the p-nitrophenyl ethyl esterase mutant. The p-nitrophenyl ethyl esterase mutant is obtained by mutating an amino acid sequence of wild p-nitrophenyl ethyl esterase pnbA as shown in SEQ ID NO.1 according to one or a combination of more of the following modes: leucine at the 273rd site is mutated into aspartic acid, phenylalanine at the 314th site is mutated into histidine, and leucine at the 362nd site is mutated into arginine. The mutant pnbA-L273D / F314H / L362R provided by the invention shows optimal catalytic performance (E = 47.16) for racemization-acetic acid pinyl hydrate, the enantiomeric excess value of the mutant is 95.13%, the conversion rate of 1S, 5R-acetic acid pinyl hydrate is 90.42%, the enantioselectivity of the mutant is obviously higher than that of a wild type, and the mutant has great application potential in biological catalytic synthesis of monocyclic monoterpenoid chiral alcohols.

The invention relates to a method for preparing a nerofloxacin chiral piperidylamine intermediate, which comprises the following steps of: carrying out condensation reaction on 5-hydroxy nicotinic acid which is simple and easy to obtain and is used as a raw material and different alcohols, screening through a series of asymmetric catalytic hydrogenation conditions to obtain optimal reaction conditions, and under the conditions, carrying out reaction on various 3, 3 '-dihydroxy nicotinic acid and 3, 3'-dihydroxy nicotinic acid to obtain the nerofloxacin chiral piperidylamine intermediate. The 2, 5-disubstituted pyridine quaternary ammonium salt is reduced into a tetrahydropyridine product, and the C5 site enantioselectivity of the product is excellent. The preparation method comprises the following steps: selecting methyl (R)-1-benzyl-5-hydroxy-1, 4, 5, 6-tetrahydropyridine-3-carboxylic acid methyl ester as a substrate, completely hydrogenating by using platinum dioxide hydrogen, and then carrying out methyl ester reduction, dehydroxylation, Mitsunobu reaction and protecting group removal to obtain a key chiral intermediate for industrial synthesis of a quinolone antibacterial drug nemonofloxacin with high enantioselectivity and high yield.

The present application belongs to the technical field of the synthesis of chiral boron compounds, and in particular relates to an MOF-Cu(II) / CMC composite material, and a preparation method therefor and the use thereof. The preparation method for an MOF-Cu(II) / CMC composite material of the present application comprises: dropwise adding an aqueous solution of sodium carboxymethyl cellulose to an aqueous solution of a bivalent copper salt, performing solid-liquid separation, mixing obtained composite microspheres with an organic solution of trimesic acid, heating the resulting mixture, and subjecting same to solid-liquid separation, so as to obtain an MOF-Cu(II) / CMC composite material. The MOF-Cu(II) / CMC composite material is used in an asymmetric chiral boron addition reaction. The reaction is performed at room temperature, involves mild conditions, is applicable to a wide range of substrates and has a high yield and enantioselectivity. Moreover, the method can achieve the synthesis of a chiral organic boride in a solvent having simple components, providing an efficient new method for the preparation of drug molecules and active intermediates, and also broadening the range of substrates used for the preparation of chiral organic borides.

The invention discloses a compound containing a bicyclic hemiketal structure and a preparation method thereof, alkynyl allyl carbonate is used as a raw material, in the presence of a nucleophilic catalyst, alkynyl allyl carbonate reacts with a benzoylacetonitrile derivative, ABB'multi-component reaction is carried out through a continuous [5 + 1] / addition / cyclization reaction sequence, and the compound containing the bicyclic hemiketal structure is obtained. Bicyclic hemiketal derivatives commonly seen in natural product structures are obtained with good to excellent diastereoselectivity. The method has the advantages of good diastereoselectivity products, excellent chemical selectivity, greenness, mild reaction conditions, convenience in operation, few byproducts and the like, the synthesis steps are good in economy, and four chemical bonds and three continuous chiral centers are simultaneously constructed through one-step operation. Meanwhile, the compound with the bicyclic hemiketal structure has important application value in multiple fields of medicinal chemistry, natural product chemistry, traditional Chinese medicine chemistry and the like, and an efficient preparation means and a series of candidate compounds are provided for development of functionality or biological activity of related compounds with the bicyclic hemiketal / hemiacetal structure.

The invention discloses a chiral alpha-amino acid with a C3 symmetric structure and a preparation method and application thereof, the chiral alpha-amino acid with the C3 symmetric structure provided by the invention is used as an ion pair catalyst, and the structure of the chiral alpha-amino acid with the C3 symmetric structure is more stable than that of other ion pair catalysts due to the C3 symmetric structure; and meanwhile, the chiral phosphamide compound is successfully constructed with relatively high yield (70-80%) and enantioselectivity (80-95%), so that the chiral phosphamide compound has excellent catalytic performance, and the problem that the chiral phosphamide compound is difficult to construct by a traditional ion pair catalyst is solved.

The application belongs to the field of organic synthesis and particularly relates to a synthesis method of polysubstituted indole propionate derivatives. Aryl acetate compounds and sulfonyl indole compounds are used as raw materials, and the reaction is carried out through an isothiourea organic small molecule catalyst. The reaction raw materials are simple and easy to obtain, the reaction conditions are mild, the operation is simple, the reaction time is short, the reaction has good diastereoselectivity and high yield, the synthesis method of the polysubstituted indole propionate derivatives overcomes the defects and deficiencies of the existing synthesis method, and has the characteristics of high efficiency, simplicity and wide universality.

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.

Catalytic systems capable of catalyzing enantioselective C-H functionalization reactions are described, and methods of use thereof are described. These catalytic systems contain an iron complex as a host catalyst, and a diammonium guest template as a co-catalyst. The iron-based main catalyst contains a crown ether phthalocyanine ligand. The diammonium guest template is a bidentate compound with chirality. The iron-based host catalyst and the bidentate ammonium guest template can provide a complex spatial environment for stereotactic and site-selective C-H functionalization, such as C-H amination. For example, enantioselective C-H amination reactions carried out using the disclosed methods can achieve high enantiomer ratios (i.e., at least 2: 1) and optionally high yields (i.e., at least 30%).

The application belongs to the field of organic synthesis, and discloses a method for preparing chiral 2-(1,3-diarylallyl)malonate by using a Pd / phosphine oxygen bidentate phosphine phenol ligand catalysis, which comprises the following steps: under a protective atmosphere, mixing P, O-bidentate phosphine phenol ligand, a palladium catalyst, N, O-bis(trimethylsilyl)acetamide, a malonate nucleophilic reagent and an allyl acetate electrophilic reagent in dichloromethane, and reacting to obtain chiral 2-(1,3-diarylallyl)malonate product. The system has the advantages of high enantioselectivity, high catalytic efficiency, wide substrate application range and mild conditions.

The invention discloses a method for catalytically synthesizing alpha-disubstituted ester, amide, malonic acid monoester or monoamide from disubstituted Meldrum's acid. By developing a new strategy for promoting the ring-opening reaction of the disubstituted Meldrum's acid by alkali, the disubstituted malonic acid monoester or monoamide can be efficiently prepared, and compared with the previous method, the strategy can obtain the target product at the room temperature at the yield of 99%. The method successfully breaks through the limitation of the existing disubstituted malonic acid monoester synthesis method, and enriches the types of target compounds. Besides, a series of novel disubstituted malonic acid monoesters are obtained, and simple chemical conversion is applied to obtain a series of disubstituted malonic acid derivatives with quaternary carbon centers. Then, under the action of a chiral organic catalyst, chiral disubstituted malonic acid monoester is obtained with high yield and high enantioselectivity. And a solid foundation is laid for subsequent application of the compounds in subjects of materials, medicines and the like.

The invention discloses a flaky supramolecular chiral copper catalyst based on molecular self-assembly and application thereof, and belongs to the technical field of asymmetric catalysis, the flaky supramolecular chiral copper catalyst is prepared by the following preparation method: dissolving L-ThrC10-20 in a solvent, and stirring to obtain a methanol solution of the L-ThrC10-20; adding ultrapure water into the system, and stirring to obtain a sheet-shaped supramolecular assembly body L-ThrC10-20-NS; and adding Cu < 2 + >, and stirring to obtain the flaky supramolecular chiral copper catalyst L-ThrC16-NS-Cu (II). According to the invention, the flaky supramolecular chiral copper catalyst L-ThrC10-20-NS-Cu (II) assembled on the basis of L-ThrC10-20 and Cu < 2 + > is successfully constructed for the first time, and the catalyst shows obvious enantioselectivity in a Diels-Alder reaction and can be used for efficiently catalyzing to generate an S-endo configuration product.

The invention relates to the technical field of synthesis of ambrota ethers, and discloses a synthesis method of ambrota ethers, the reaction is mainly carried out through a synergistic way, and in the presence of fluorinated alcohol, the strong acidic site of an imino diphosphoryl imide ester catalyst promotes protonation of a distal double bond of (3E, 7E)-homofarnesyl alcohol to form a cationic intermediate. Meanwhile, the imino diphosphoryl imide ester catalyst promotes the (3E, 7E)-homofarnesyl alcohol to be combined in an all-trans conformation manner, and guides carbocations and olefin to be subjected to stereotactic addition, so that a polyene cyclization reaction with high diastereoselectivity and enantioselectivity is realized, and the ambrota ether is finally generated. The fluorinated alcohol stabilizes the cation intermediate through a hydrogen bond, so that the activity and selectivity of the reaction are further improved. The synthesis method of ambrota ether is low in cost and efficient.

The invention discloses a method for preparing a chiral benzhydrol compound through asymmetric hydrogenation of o-amido benzophenone under catalysis of rhodium. The chiral rhodium catalyst is generated in situ from a metal rhodium salt and a chiral phosphine-phosphoramidite ligand in various solvents. Compared with other methods for synthesizing chiral benzhydrol, the method has the characteristics of cheap catalyst, easiness in preparation of chiral ligand, mild reaction conditions, simplicity and convenience in operation, high yield, high enantioselectivity and the like, and can be applied to large-scale preparation of chiral benzhydrol compounds. The method is also suitable for efficient preparation of the rice plant growth regulation inhibitor (S)-Inabenide, the yield can reach 92%, the enantioselectivity can reach 96%, and the method has good industrial application prospects.

The invention discloses a method for olefin enantioselective carbon oxidation through photoelectric synergistic vanadium catalysis, and belongs to the technical field of photoelectric asymmetric catalysis. A bulk chemical organic solvent, an olefin substrate and an N-hydroxyimide substrate are used as raw materials, a vanadium catalyst, an electrolyte and a cathode hydrogen evolution reagent are added, and the enantiomerically enriched olefin carbon oxidation chiral product is prepared under the conditions of electrification and irradiation of an ultraviolet lamp. The method has the characteristics of simple and easily available raw materials, mild reaction conditions, simple and efficient reaction operation, simple and convenient reaction post-treatment, good functional group compatibility, large-scale preparation potential and the like.

The present invention discloses a chiral α -hydroxyamide derivative, and its synthesis method and application. The synthesis method includes: in the presence of a chiral thiourea catalyst, an aromatic amine and α -carbonyl acylsilane undergo a catalytic asymmetric nucleophilic addition reaction under light in a solvent to form a chiral α -hydroxyamide derivative. The reaction of the present invention uses light as the driving force to achieve green synthesis; secondly, the introduction of the chiral thiourea catalyst not only significantly improves the enantioselectivity but also avoids the use of metal catalysts, which conforms to the concept of green chemistry. In addition, the reaction substrates α -carbonyl acylsilane and aromatic amine are both inexpensive and easily accessible chemicals, thereby reducing the synthesis cost and improving the feasibility and practicality of the method.

The invention discloses a benzoxphosphine ligand and a complex and application thereof. The structure of the benzoxphosphine ligand is shown as a formula (I), in the formula (I), R1 is alkyl or aryl substituted oxazolidinyl or imidazoline, R2 is alkyl and / or aryl, and R3 is at least one of fluorine, carbazolyl and 2, 6-dimethoxyphenyl. According to the benzoxphosphine ligand disclosed by the invention, the metal iridium complex can be used as a catalyst to be applied to an asymmetric hydrogenation reaction of alpha-phenyl vinyl diethyl phosphate, and has excellent activity and relatively high enantioselectivity; moreover, the benzoxphosphine ligand disclosed by the invention can be directly synthesized from simple and easily available chiral aldehyde, and the preparation method is simple and easy to operate.

The invention discloses a biological catalytic synthesis method of chiral 2-amino-1-methylenepropanamide and an enzyme catalyst of the chiral 2-amino-1-methylenepropanamide. According to the present invention, one or more key amino acids in the amide hydrolase derived from Rhodococcus erythropolis AJ270 are subjected to mutation to obtain the mutant, the mutant has characteristics of high or reverse enantioselectivity when the hydrolysis reaction of the racemization 2-substituted-2-amino-1-methylene propanamide substrate is catalyzed, and the chiral compound is obtained with the high ee value; and an enantiomer of a wild type amide hydrolase catalytic product can be obtained. A method for preparing chiral 2-substituted-2-amino-1-methylene propanamide by using the mutant through biological catalysis has the characteristics of simplicity and convenience in operation, high reaction efficiency, mild reaction conditions, high enantioselectivity, easiness in product separation and high product purity, and has a very good application prospect.

This invention belongs to the field of organic synthesis technology and relates to a precursor of an obisec key intermediate and a method for preparing the key intermediate. The method involves a [4+2] cycloaddition reaction of 4-trifluoromethylaniline, propionaldehyde, and N-vinylformamide under the catalysis of chiral phosphoric acid, yielding the obisec key intermediate precursor with high enantioselectivity. N -((2) R 4 S )-2-ethyl-6-trifluoromethyl-1,2,3,4-tetrahydroquinoline-4-yl)formamide; subsequently, the key intermediate of obisetri can be obtained through a deprotection reaction under acidic conditions. The method provided by this invention uses a small amount of chiral catalyst and commercially available reagents to efficiently obtain the key intermediate of obisetri in just two steps. R 4 S )-2-ethyl-6-trifluoromethyl-1,2,3,4-tetrahydroquinoline-4-amine; under mild conditions without the need for chiral resolution, the utilization of starting materials is greatly improved, thereby significantly increasing the yield of the target product and the economic efficiency of the process.

The present invention relates to a method for the asymmetric deuterium functionalization of alkenes promoted by chiral thiols and deuterated water. Specifically, the present invention provides a method for synthesizing compounds with high deuteration rates and high optical activity through visible light-catalyzed deuterium functionalization of alkenes, using inexpensive deuterated water as a deuterium source and a peptide- or sugar-derived thiol as a chiral source. The method has the advantages of a short synthetic route, simple operation, readily available deuterium sources, no metal requirements, broad substrate applicability, high deuteration rates and overall yields, and high enantioselectivity.

The application belongs to the technical field of chiral catalysis and medicine, and particularly relates to a dendritic chiral phase transfer catalyst, a structural formula of which is shown as formula (I) or formula (II). A series of chiral phase transfer catalysts based on soluble dendritic macromolecules are synthesized by changing the number of repeated carbon chains on the core molecular structure, and it is found through catalyzing asymmetric alkylation of amino acid derivatives that the dendritic chiral phase transfer catalysts provided by the application have excellent yield and enantioselectivity in catalyzing preparation of chiral amino acid derivatives.

The invention discloses a photosensitive manganese catalyst and preparation and application thereof, the structure of the catalyst is as shown in formula I or formula II: # imgabs0 # general formula I or formula II, X is selected from one of-OTf and-OAc. According to the structure of the catalyst disclosed by the invention, an anthraquinone group is introduced to a proper position of a non-heme N4 ligand, so that a novel compound with a photosensitive function is coordinated with metal manganese to form the photosensitive manganese catalyst shown as a formula I or a formula II. The catalyst is bifunctional, realizes concerted catalysis of metal and light, and is high in catalytic activity and excellent in enantioselectivity (ee value can reach 98%). The catalyst takes O2 as an oxygen source, can be applied to asymmetric epoxidation of olefin, asymmetric oxidation of thioimine and other reactions, conforms to the green chemistry concept, and has a very good application prospect.

The application discloses a kind of solid supported manganese catalyst and its preparation method and application, the preparation process of the catalyst includes complexing organic ligand with metal manganese salt, forms catalytic active unit, and then polymerizes with comonomer, obtains the solid supported manganese catalyst as shown in formula I or II.The solid supported manganese catalyst belongs to heterogeneous chiral catalyst, with higher catalytic activity and excellent enantioselectivity (ee value is as high as 98.3%), because it is insoluble in reaction solvent, easy to separate and recover with reaction system, with good stability.And it can be combined with continuous flow catalysis, maintain high catalytic activity for a long time, can be applied in the asymmetric epoxidation reaction of alpha, beta-unsaturated carbonyl compound.

The application belongs to the technical field of organic chemical synthesis, and particularly relates to a nitrogen center chiral base derivative, a preparation method and application thereof. The preparation method of the nitrogen center chiral base derivative provided by the application can effectively synthesize a base with only a nitrogen chiral center by using a tetrahydrodibenzo-diazocine compound as a raw material and through chiral phosphoric acid catalyzed amination reaction. Moreover, the synthesis method provided by the application has the advantages of high efficiency, simple steps and strong enantioselectivity, is suitable for industrialized production of chiral bases and derivatives thereof, and provides a new approach for research and application of chiral compounds. Meanwhile, the base derivative prepared by the application is a base molecule with a nitrogen center chirality, and has wide application prospects in the fields of molecular recognition, DNA binding, supramolecular chemistry, material science, asymmetric catalysis and drug development.

The invention relates to the technical field of catalysts, in particular to a chiral diphosphine ligand modification-based ruthenium-carbon hydrogenation catalyst as well as a preparation method and application thereof. The method comprises the following steps: preparing a nitrogen-containing defect carbon carrier; loading ruthenium and reducing; pre-coating the confinement by using an ionic liquid A; introducing a chloride ion template microenvironment; carrying out coordination with a chiral diphosphine ligand; weak coordination anion sizing is realized through the treatment of bis (trifluoromethanesulfonyl) imide silver; and finally introducing chiral ionic liquid B to construct an outer network. The catalyst realizes high enantioselective conversion of a prochiral substrate while maintaining high hydrogenation activity through a multi-layer chiral microenvironment synergistic effect, is excellent in cycling stability, and solves the technical problem that the activity and selectivity of a heterogeneous chiral catalyst are difficult to consider at the same time.

This invention discloses an axially chiral 1,4'-biquinolinone and its derivatives, and a synthetic method thereof. The method uses MBH carbonate and quinoline-2(1 H Using β-ketones as raw materials, (DHQD)₂PYR as catalyst, and DME as solvent, a centrally chiral β-substituted allyl intermediate was synthesized; then, using iron powder as a reducing agent and acetic acid as solvent, enantiomeric enriched centrally chiral γ-lactam compounds were obtained; finally, using DBN as a base and DME as solvent, enantiomeric enriched compounds were obtained. (S) -Axial chiral 1,4'-biquinolinone or its derivatives. The method of this invention has mild reaction conditions, readily available raw materials, high enantioselectivity of the product, and excellent yield. The synthesized 1,4'-biquinolinone or its derivatives can be further used to synthesize novel substituted quinolinone phosphonate compounds, and to synthesize drugs with antibacterial, antimalarial, anticancer, antitumor, or herbicidal activities, showing broad application prospects.

The present invention relates to a process for the enantioselective preparation of chiral 4-substituted 2-oxazolidinones of formula (la) or (lb) via asymmetric hydrogenation of the corresponding 4-substitued 2-oxazolones of formula (II) using a combination of palladium or nickel and a chiral bidentate P-ligand as catalyst. The oxazolidinones can then be converted to important chiral building blocks such as enantiopure chiral aminoalcohols and haloamines via decarboxylative ring opening reaction.

The application discloses a rhodium-catalyzed desymmetrization hydroformylation method for constructing polychiral center carbon ring nucleosides. The method for constructing polychiral center carbon ring nucleosides comprises the following steps: under the condition of an inert atmosphere, an acetylacetone dicarbonyl rhodium metal precursor and a chiral ligand are added into an organic solvent to prepare a catalyst solution, the catalyst solution is mixed with a substrate, and a reaction is carried out under the condition of a hydrogen atmosphere and a carbon monoxide atmosphere; after the reaction is completed, filtration and purification are carried out, and polychiral center cycloalkyl aldehyde is obtained; and the aldehyde group is converted to obtain the polychiral center carbon ring nucleosides. The method for constructing polychiral center carbon ring nucleosides has the advantages of high selectivity, wide substrate compatibility, high reaction efficiency, easy conversion of products, and the like. The whole reaction process can obtain polychiral center cycloalkyl aldehyde in one step with extremely high enantioselectivity and diastereoselectivity, the aldehyde group is converted, polychiral center carbon rings can be obtained with high yield, high dr value and high ee value, and the method is simple and easy to operate.

The application discloses a preparation method of 3,4-dihydropyran derivatives, and a reaction formula is as follows: the unactivated propenal and the weak polar olefin which are simple in structure and low in material cost are used as starting materials, the unactivated propenal and the weak polar olefin which are weak in reactivity can participate in [4+2] cycloaddition, and the 3,4-dihydropyran derivatives with high purity can be prepared; the preparation process is simple in operation, high in yield and excellent in diastereoselectivity, can effectively convert low-cost raw materials into high-value-added compounds, and provides an economic and efficient synthesis strategy for related industries.