900results about How to "High enantioselectivity" patented technology

The present invention provides a method for manufacturing polycarbonate, which has a high conversion rate of a propylene oxide material into a polymer and can control stereoregularity of the macromolecular structure, and a catalytic compound for the manufacturing method.

The manufacturing method of the present invention is a method for manufacturing a polycarbonate copolymer by copolymerizing an epoxide compound as a monomer with carbon dioxide in the presence of a planar tetracoordinate-type cobalt-Schiff base complex, wherein a ligand of the Schiff base is N,N′-bis(2-hydroxybenzylidene)ethylenediamine, N,N′-bis(2-hydroxybenzylidene)phenylenediamine, or a derivative thereof, and a methyl group substituted with an amino group having an asymmetrical carbon atom or an asymmetrical axis is introduced to the 3- and/or 3′-position of the benzene ring derived from the salicyl group. In addition, the catalytic compound of the present invention is a cobalt-Schiff base complex, wherein a methyl group substituted with an amino group having an asymmetrical carbon atom or an asymmetrical axis is introduced to the 3- and/or 3′-position of the salicyl group.

The invention relates to a method for preparing (S)-(4-chlorphenyl)-(pyridine-2-yl)-methanol by utilizing microbial catalysis, and belongs to the technical field of biological catalysis. According to the method, 4-chlorphenyl-(pyridine-2-yl)-ketone is subjected to asymmetrical reduction by utilizing kluyveromycessp (CCTCCM 2011385) whole cells to synthesize the (S)-(4-chlorphenyl)-(pyridine-2-yl)-methanol. The method comprises the following steps of: sieving a microbe which has high-stereoselectivity carbonyl reductase activity on a prochiral ketone substrate, determining a series of conditions of asymmetrical reduction reaction, such as reaction temperature, pH, the concentration of cells, the concentration of the substrate and reaction time and additives (including various secondary solvents, polyethyleneglycol (PEG), phosphates and the like), wherein the enantiomer excess value and yield of the (S)-(4-chlorphenyl)-(pyridine-2-yl)-methanol serving as a product can reach 86.7 percent e.e and 92.1. The product is separated and extracted initially by silicagel column chromatography, so that the purity of the separated product is 99.2 percent, and the extraction yield is 56.7 percent.

The invention discloses a synthesis method of metaraminol bitartrate, and in particular provides a method for synthesizing metaraminol bitartrate by using a chiral catalysis method. The synthesis method comprises the steps: catalyzing a chiral addition reaction of hydroxybenzaldehyde and nitroethane by using a chiral catalyst system consisting of cinchona alkaloid, copper acetate hydrate and less imidazole to obtain an addition product with a dominant required spatial configuration, and then reducing nitro by using hydrogen in the presence of Pd-C to obtain amine to obtain aramine, and salifying the aramine with L(+)-tartaric acid to obtain a final product metaraminol bitartrate. According to the synthesis method, an enzyme catalyst is prevented from being used, a raw material of the synthesis reaction is easily available, the chiral catalyst is easily purchased or prepared self, the synthesis steps are relatively less, the chiral control efficiency is higher, the enantioselectivity is high, the yield is good, the reaction operation is easily controlled, and is safe and reliable, and the foundation is laid for the later industrialized amplification production.

The invention discloses a phosphine ligand and an enantiomer or a racemic body thereof and preparation methods and applications thereof. The structural formulae of the phosphine ligand and the enantiomer or the racemic body are shown in the specifications; a phosphine ligand compound has a novel framework; complete transfer of planar chirality to axial chirality in a synthesis process is realized through a desymmetrization reaction; a synthesis method is simple and economical; during preparation of a chiral ligand, common complex chiral splitting processes are avoided; and an obtained chiral ligand has the advantages of high reaction activity, high enantioselectivity and the like in a model reaction, can be applied to catalytic reactions of a plurality of metals such as palladium, rhodium, nickel, copper, iridium, ruthenium, iron, cobalt, gold, platinum and the like, and can have a very good catalytic effect.

[Problems] To provide an efficient process for producing an optically active epoxy compound.

[Means For Solving Problems] The process for producing an optically active epoxy compound comprises asymmetrically epoxidizing an unsaturated compound with an oxidizing agent in the presence of an optically active titanium-salen complex, an optically active titanium-salalen complex or an optically active titanium-salan complex, with addition of a buffering agent or a buffer solution. The process can inhibit catalyst degradation, reduce the amount of the catalyst used in the reaction, and inhibit a by-product, compared with the prior art, and can provide an optically active epoxy compound in high chemical yield and optical yield and with high quality, and therefore is an industrially useful process.

The present invention relates to a production method capable of producing an optically active α-hydroxyphosphonic acid and its derivatives with sufficiently high enantioselectivity not only for aromatic aldehydes but also for aliphatic aldehydes, and more specifically to a method of producing an optically active α-hydroxyphosphonic acid and its derivatives, characterized in that an optically active aluminum(salalen) complex represented by any one of the following formulae (I), (I′), (II) and (II′):

[wherein R¹s are each alkyl group or aryl group independently; R²s are each alkyl group or aryl group independently; R³s are each alkyl group or aryl group independently, and two R³s may bond with each other to form a ring; R⁴s are each hydrogen atom, halogen atom, alkyl group, alkoxy group, nitro group, or cyano group independently; R⁵ is alkyl group; and X¹ is halogen atom, alkyl group, alkoxy group, acetoxy group or toluenesulfonyloxy group] is used as a catalyst to asymmetrically hydrophosphonylate an aldehyde with phosphonic acid or its derivatives.

The invention discloses a chirality dihydrogen silane compound. The chirality dihydrogen silane compound is as shown in the formula IV. In the formula IV, X represents a chiral carbon atom. The invention further discloses a synthetic method for the chirality dihydrogen silane compound. The method comprises the following steps: using olefin shown in the formula I and silane shown in the formula II as raw materials, and using a chiral CoX2-OIP complex compound as a catalyst, in the existence of a reducing agent, reacting to obtain the chirality dihydrogen silane compound shown in the formula IV. The synthetic method is suitable for different types of the olefins, the reaction condition is moderate, the operation is simple and convenient, and the atomic economy is high. The reaction does not need to be added with any other toxic transition metal ions, the reaction yield is better and is 53%-97% generally, and the enantio-selectivity is higher and is 81%-99% and gt generally. The provided chirality dihydrogen silane compound shown in the formula IV can be used for synthesizing a chiral alcohol compound, a chiral silicon alcohol compound, a chiral polysubstituted silane compound and so on.

A catalysis system used by a method for synthesizing chiral cyclic amine through catalyzing asymmetric hydrogenation of quinolin-3-amine by iridium is a chiral diphosphine complex of iridium. A reaction is carried out under the following conditions: the temperature is 25-70DEG C; a solvent is a toluene/tetrahydrofuran mixed solvent (V/V=3:1); the pressure is 2-14atm; a ratio of a substrate to a catalyst is 25:1; and the catalyst is a (1,5-cyclooctadiene)iridium chloride dimer and chiral diphosphine ligand complex. A corresponding chiral cyclic amine derivative is prepared from quinolin-3-amine, and the enantiomeric excess value can reach 94%. The method has the advantages of simple and practical operation, easily available raw material, high enantioselectivity, good yield, and green, atom-economic and environmentally-friendly reaction.

The invention relates to a method for preparing a chiral alpha-hydroxy-beta-keto ester compound by the application of a zirconium catalyst with a chiral diaminocyclohexane derivative as a ligand. The method comprises the following process: in the presence of a zirconium complex with a diaminocyclohexane derivative as a ligand, a beta-keto ester compound and an oxidizing agent are contacted with each other in an inert solvent, wherein dosage of a catalyst is 0.5-50 mol% of dosage of the beta-keto ester compound; dosage of the oxidizing agent is 100-2000 mol% of dosage of the beta-keto ester compound; and reaction temperature is 0-100 DEG C. yield of the alpha-hydroxy-beta-keto ester compound reaches up to 99%, and ee value reaches up to 98%. According to the invention, the zirconium catalyst with the diaminocyclohexane derivative as a ligand that is easy to synthesize, is low-cost and has stable performance is used, and then the alpha-hydroxy-beta-keto ester compound can be effectively prepared. By the method, very high yield and good enantioselectivity can be gained. The method of the invention is simple to operate, is low-cost and is suitable for industrialization.

The invention provides a chiral pyrrolidine functionalized imidazolium salt, and a preparation method and an application thereof. The chiral pyrrolidine functionalized imidazolium salt is bromized 1-[2-(S)-(pyrrolidyl)methyl]-3-benzoyl methyl imidazole hydrobromide. The preparation method of the chiral pyrrolidine functionalized imidazolium salt comprises the following steps of: by taking natural amino acid L-proline as the starting raw material, obtaining the chiral pyrrolidine functionalized imidazolium salt through a plurality of conventional organic synthetic reactions such as Boc acylation, carboxylic acid reduction, hydroxyl sulfonylation, nucleophilic substitution of imidazole anions, quaternization of halohydrocarbon and de-Boc protection. The chiral pyrrolidine functionalized imidazolium salt provided by the invention is capable of catalyzing asymmetric Michael addition reaction of cyclohexanone and nitroolefin, and has extremely high diastereoselectivity and enantioselectivity.

The invention discloses a method for performing the asymmetric catalytic hydrogenation of ketone-derived N-alkylimine. In the method disclosed by the invention, the catalytic hydrogenation of the ketone-derived N-alkylimine is performed in the presence of a chiral catalyst formed by a chiral diamine ligand and a transitional metal to obtain a chiral amine product with high yield and high enantioselectivity. The enantiomeric excess of a chiral amine product formed by the hydrogenation of an acyclic N-alkylimine substrate may reach 98 percent ee; and the enantiomeric excess of a chiral amine product formed by the hydrogenation of an exocyclic N-alkylimine substrate may reach over 99 percent ee. The method disclosed by the invention realizes the asymmetric catalytic hydrogenation of ketone-derived N-alkylimine with high enantioselectivity, and the obtained chiral amine product is an important medicinal and material intermediate and has a bright actual application prospect.

The invention discloses a method for synthesizing a chiraltetrahydro naphthalenederivate through asymmetric hydrogenation on isoquinoline by means of an iridium catalyst. A catalysis system applied in the method is a chiral bi-phosphine complex of metal iridium. The reaction is carried out under the conditions that the temperature is 25-60 DEG C; the volume ratio of tetrahydrofuran to dichloromethane in a solvent, namely a mixed solvent of tetrahydrofuran and dichloromethane is 1:1; the pressure is 13-50 Mpa; the ratio of a substrate to a catalyst is 50:1; the catalyst is a coordination compound of a (1,5-cyclooctadiene) iridium chloridedipolymer and a chiral bi-phosphine ligand. The corresponding chiral 1-position or 3-position substituted tetrahydro naphthalenederivate through hydrogenation on isoquinoline, and the enantiomeric excess of the derivate can reach 96%. The method is simple and practical in operation, raw materials are easy to obtain, the enantioselectivity is high, the yield is high, the reaction has atom economy, and the environment is friendly.

The invention provides a method for synthesizing 1,6-eneyne compounds. The method is an effective method which synthesizes the optically active 1,6-eneyne compounds with high regioselectivity and enantioselectivity by using iridium complex as a catalyst as well as allyl carbonate compounds and a propargyl nucleophilic reagent as raw materials. The method has the advantages of readily available catalyst, high catalytic activity, mild reaction temperature, wide substrate application range and high product regioselectivity and enantioselectivity.

The invention relates to the technical field of biology, and relates to a lipase mutant and uses thereof. The mutant is obtained from wild type candida antarctica lipase B (CALB) through mutation. The invention particularly relates to the lipase mutant, a preparing method thereof, and a method of preparing S-configuration ibuprofen type compounds with optical activity through catalysis of hydrolysis of ester derivatives of the ibuprofen type compounds by utilization of the lipase mutant and through kinetic resolution. The wild type candida antarctica lipase B is subjected to mutation to obtain the modified lipase. The lipase is expressed in pichia pastoris engineering bacteria. The lipase comprises an amino acid sequence having at least 85% of identity with the SEQ ID NO.02. The 189 site residue corresponding to the SEQ ID NO.02 of the lipase is an aromatic amino acid residue and the 190 site residue corresponding to the SEQ ID NO.02 of the lipase is a nonpolar amino acid residue. By subjecting the wild type candida antarctica lipase B to mutation, the enantioselectivity of the lipase to the ibuprofen type compounds is improved.

The invention relates to chirality phosphine ligand metal complex catalyse system, which is composed by complex formed by ligand and metal Rh, Ru, Ir, Pt or Pd or ligand and metal precursor in of 1-2 mol ratio. The phosphine ligand is a kind of effective chirality phosphate ligand composed by D-mannitol or L-mannitol after reaction. The catalyst composed by the chirality ligand and rhodium metallic compound in asymmetry hydrogenation reaction can work in room temperature. With a wide applied range, catalyst's activation and stereoselectivity is not influenced from normal pressure to high pressure. Reaction time is 1-24 hours. Mol ratio of ligand and metal rhodium compound is 1:1-2:1. Ratio of reactant and catalyst is 100-10,000.

The invention discloses nanogel modified by ionic liquid and loaded with a chiral catalyst and a preparing method and application thereof. The nanogel is characterized in that polymerization of functional monomers, a crosslinking agent, sodium dodecyl sulfate, chiral monomers and the imidazolium ionic liquid is initiated by initiator ammonium persulfate in solvent water to form a crosslinking copolymer, and the nanogel modified by the ionic liquid and loaded with the chiral catalyst is obtained through dialysis. The invention further discloses the preparing method of the nanogel modified by the ionic liquid and loaded with the chiral catalyst and application of the nanogel to an asymmetric Aldol reaction. The ionic liquid is introduced into preparation of chiral nanometer hydrogel, and a simple and effective path is provided for preparing a novel chiral catalyst which is high in catalytic activity and selectiveness, easy to separate, capable of being used repeatedly in an aqueous solution.

beta-keto esters are prepared by way of a lipase-catalyzed transesterification. The synthetic methodology provides a simple scheme for the synthesis of optically active beta-keto esters that are useful building blocks and starting materials for natural product synthesis. Moreover, the methodology employs mild, solvent-free conditions. The methodology may also be employed for resolving racemic alcohols.