1687 results about "Enantio selectivity" patented technology

The present invention provides compositions comprising metal complexes, and related methods. In some embodiments, metal complexes of the invention may be useful as catalysts for chemical reactions, including metathesis reactions, wherein the catalysts exhibit enhanced activity and stereoselectivity. In some embodiments, the invention may advantageously provide metal complexes comprising a stereogenic metal atom. Such metal complexes may be useful in enantioselective catalysis.

The present invention is directed to enantioselective polyelectrolyte complex films. Further, said films may be free or isolated membranes, or coatings on substrates such a porous substrates, capillary tubes, chromatographic packing material, and monolithic stationary phases and used to separate chiral compounds. The present invention is also directed to a method for forming such enantioselective polyelectrolyte complex films.

The tetracycline class of antibiotics has played a major role in the treatment of infectious diseases for the past 50 years. However, the increased use of the tetracyclines in human and veterinary medicine has led to resistance among many organisms previously susceptible to tetracycline antibiotics. The modular synthesis of tetracyclines and tetracycline analogs described provides an efficient and enantioselective route to a variety of tetracycline analogs and polycyclines previously inaccessible via earlier tetracycline syntheses and semi-synthetic methods. These analogs may be used as anti-microbial agents or anti-proliferative agents in the treatment of diseases of humans or other animals.

The invention relates to a chiral spiro aminophosphine ligand compound and a synthesis method as well as an application thereof. The chiral spiro aminophosphine compound contains a compound with a structure shown in I, or a racemic body or an optical isomer thereof, or a catalyzed acceptable salt thereof, wherein the main structure characteristic is with a chiral spirobiindane matrix. The chiral spiro aminophosphine compound can be synthesized by taking 7-diaryl/phosphito-7'-carboxy-1, 1'-spirobiindane or substituted 7-diaryl/phosphito-7'-carboxy-1, 1'-spirobiindane as chiral starting materials, which has optical activity and spiro matrix. The chiral spiro aminophosphine compound can be used as a chiral ligand for an asymmetrically catalyzed hydrogenation of an iridium catalyzed carboxy compound and achieves high yield and enantioselectivity (97%ee). The reactive activity is also high and the consumption of the catalyst can be reduced to 0.01% molar.

A method for preparing an enantiomeric chromane, by asymmetrically hydrogenating a chromene compound in the presence of an Ir catalyst having a chiral ligand. The method includes the enantioselective preparation of enantiomeric equol. A preferred Ir catalyst has a chiral phosphineoxazoline ligand. Enantiomeric chromanes of high stereoselective purity can be obtained.

The invention discloses an enzyme-chemocatalysis racemization removing preparation method for L-glufosinate-ammonium. According to the method, a one-pot reaction manner is adopted, under the molecular oxygen, immobilization D-amino acid oxidase catalyzes D-enantiomer in an enantioselectivity mode into 2-imino-4-(hydroxy methyl phosphonyl) butyric acid in a dehydrogenation mode, and palladium-ammonium formate catalyzes 2-imino -4-(hydroxy methyl phosphonyl) butyric acid into DL-glufosinate-ammonium in an in-situ reduction mode. Hydrogen peroxide produced in the process is efficiently decomposed into water and oxygen through catalase. Complete reacemization removing of DL-glufosinate-ammonium and efficient preparing of L-glufosinate-ammonium are achieved through biological oxidation-chemical reduction circulation. The method has the advantages that the process is simple, cost is low, environmental friendliness is achieved, and energy is saved. High-concentration DL-glufosinate-ammonium can be converted into L-glufosinate-ammonium. The yield is 90%, the optical purity of the product is 99%, and the method is suitable for industrial production of L-glufosinate-ammonium.

The invention relates to an asymmetric synthesis method for botanical pesticide nicotine and anabasine. The low-cost and easily acquired 2,5-dibromopyridine is taken as an initial raw material and is processed in two steps, so that the hydrogenation precursor annular imine is acquired; under the induction of the chiral catalyst, iridium-phosphine oxazoline, an important hydrogenated product intermediate is acquired through high enantioselectivity; the intermediate is processed in two steps, so that L-nicotine is acquired; the intermediate is converted into L-anabasine in one step. The asymmetric hydrogenation of the annular imine containing pyridine gene is taken as the key step of the method. According to the invention, the chiral catalyst, iridium-phosphine oxazoline, is used for catalyzing the asymmetric hydrogenation and the key intermediate with ultrahigh ee value is acquired, and then the methylation and reduction bromine-removing two-step reaction is performed for converting, so that the target products, natural nicotine and anabasine, are acquired. According to the invention, the operation is stable, the purity is high and the cost is low.

The invention relates to an enzymatic method for the enantioselective reduction of organic keto compounds to the corresponding chiral hydroxy compounds, an alcohol dehydrogenase from Lactobacillus minor and a method for the enantioselective production of (S)-hydroxy compounds from a racemate.

The invention provides a novel method for preparing optically pure substituted [(pyridyl methylene) sulfinyl]-1H-benzimidazole sulphoxide compound by enantioselective synthesis. The method requiring protection is to directly and asymmetrically oxidize prochiral thioether into a corresponding optically pure sulphoxide compound or a sulphoxide compound rich in single enantiomer by a mild and cheap oxidizing agent in the presence of a complex compound catalyst formed by an accessible and stable (+)- or (-)- tartaric acid diamide ligand shown in a general formula and titanium. Therefore, optically pure omeprazole, lansoprazole and pantoprazole can be obtained, wherein R8, R9, R10 and R11 are the same or different, and are selected from hydrogen, alkyl, aralkyl, aryl, organic polymers or a silica loading body.

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 simple stereoselective synthesis method of sex pheromones of hyphantria cunea, which relates to epoxypropane compounds. The sex pheromones of hyphantria cunea III[(9S,10R)-9,10-epoxy-(3Z,6Z)-3,6-heneicosenediene] and IV[(9S,10R)-9,10-epoxy-(3Z,6Z)-3,6-heneicosenetriene] are prepared from cheap and readily available 2-propargyl alcohol serving as raw materials by eight steps with high efficiency, high enantioselectivity and high yield, wherein the total yield of (9S,10R)-III is 36 percent; the total yield of (9S,10R)-IV is 33 percent; and enantiomer excess e is more than 99 percent. The method has the advantages that: the operation and separation of each step are simple; the yield is high; all the adopted reagents are common reagents which are cheap and readily available; and the production line is short. The method is suitable for industrial production.

The invention discloses a method for preparing cis-pinane by asymmetric catalytic hydrogenation of alpha-pinene, and belongs to the chemical engineering field. The method comprises the process steps: in a nitrogen atmosphere, heating RhCl3.3H2O to dissolve in an ethanol solution, and forming a solution A; dissolving newly recrystallized PPh3 in a deoxygenated ethanol, and forming a solution B; adding the solution B into the solution A, refluxing for a certain period of time, filtering under reduced pressure while being hot, washing with deoxygenated ether, carrying out vacuum drying to obtain a rhodium phosphine complex RhCl(PPh3)3; and adding the prepared rhodium phosphine complex RhCl(PPh3)3, an ionic liquid and alpha-pinene into a high-pressure reaction kettle according to a certain proportion, putting a cover and sealing, respectively replacing with nitrogen gas and hydrogen gas, carrying out pressure maintaining and leakage detection, and carrying out a reaction under certain conditions to prepare cis-pinane. The method has the advantages of mild reaction conditions, high conversion rate of alpha-pinene and high enantioselectivity of cis-pinane; the ionic liquid catalyst system is easily separated from the product and can be recycled; and the process flow is simple, and the energy consumption is low.

The invention discloses a preparation method and an application for phosphine-oxazoline ligand, and ionic metal complex, enantiomer or racemate thereof. The ligand and the ionic metal complex thereof have the following structural formulas. The phosphine ligand related by the invention employs biphenyl as a skeleton, and realizes completely transmission from planar chirality to axial chirality through an asymmetric desymmerization. The synthetic method is simple and economic, omits a common and complex chiral separation process in the preparation of the chiral ligand. The obtained chiral ligand has the advantages of high reactive activity, good enantiomorphous selectivity and the like in a model reaction.

The invention belongs to the technical field of asymmetric catalysis and specifically relates to a chiral nitrogen nitrogen phosphine tridentate ligand based on a ferrocene skeleton and an applicationthereof. A coordination compound is obtained by the disclosed chiral nitrogen nitrogen phosphine tridentate ligand base on the ferrocene skeleton complexed with a transition metal precursor, the complex is used as a precious metal catalyst, and is successfully applied to high efficiency asymmetric hydrogenation of aromatic ketone. Compared with other tridentate ligands, the ligand is simple to synthetize, is stable to water and air, and easy to prepare on a large scale, shows high activity and high enantioselectivity on carbon and oxygen double bond, and has greater implementation value and social and economic benefits.

The invention discloses a 6-hydroxyl quinine quaternary ammonium salt asymmetric phase transfer catalyst, a preparation method and application of the 6-hydroxyl quinine quaternary ammonium salt asymmetry phase transfer catalyst and belongs to the field of organic synthesis. In a two-phase system of an oxidizing agent, an alkaline solution and an inert solvent, the 6-hydroxyl quinine quaternary ammonium salt asymmetric phase transfer catalyst converts a beta-dicarbonyl compound into a chiral alpha-hydroxyl-beta-dicarbonyl compound; the usage quantity of the chiral 6-hydroxyl quinine quaternary ammonium salt asymmetric phase transfer catalyst is 0.5-50 mol% of the beta-dicarbonyl compound, and under the mild condition that reaction temperature is -15 DEG C-65 DEG C, the yield of the chiral alpha-hydroxyl-beta-dicarbonyl compound is larger than or equal to 90%, and the enantioselectivity is higher than or equal to 70% ee. The method is mild in reaction condition, environmentally friendly, high in reaction efficiency and suitable for large-scale production and preparation.

Disclosed herein are mixed metal-organic frameworks, Zn₃(BDC)₃[Cu(SalPycy)] and Zn₃(CDC)₃[Cu(SalPycy)], wherein BDC is 1,4-benzenedicarboxylate, CDC is 1,4-cyclohexanedicarboxylate, and SalPyCy is a ligand of the formula:

These are useful for applications such as selective gas storage, selective molecular separations, and selective detection of molecules, including enantioselective applications thereof.

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 present invention relates to a continuous process for the enantioselective catalytic hydrogenation of β-ketoesters comprising providing a catalytic hydrogenation zone and maintaining it under conditions of temperature and pressure effective for the catalytic hydrogenation of β-ketoesters; continuously supplying to the catalytic hydrogenation zone a substrate comprising a β-ketoester to be hydrogenated, a catalyst effective for enantioselective hydrogenation of the β-ketoester and hydrogen; contacting the substrate, the catalyst and the hydrogen in the hydrogenation zone for a residence time effective for at least partial enantioselective catalytic hydrogenation of the β-ketoester; (d) continuously withdrawing from the hydrogenation zone a reaction product mixture comprising enantioselectively hydrogenated β-ketoester, unreacted β-ketoester, catalyst and hydrogen; (e) supplying the reaction product mixture to a separation zone and separating at least some of the enantioselectively hydrogenated β-ketoester from the reaction product mixture; (f) withdrawing the separated enantioselectively hydrogenated β-ketoester as product; and (g) optionally supplying at least part of the remaining material from the separation zone to the hydrogenation zone.