25 results about "Stereospecificity" patented technology

The present invention relates to a catalyst for propylene polymerization, a catalyst system for propylene polymerization and preparation and use thereof. The catalyst for propylene polymerization comprises: an activated magnesium halide, a titanium compound supported on the activated magnesium halide containing at least one Ti-halogen bond, and an internal electron donor compound selected from one or more of compounds having a structure of below Formula (1), wherein R1 and R6 are each independently selected from a C1-C12 straight or branched alkyl, a C3-C15 cycloalkyl or aryl, and R′ is H, a C1-C5 straight or branched alkyl, or phenyl; R2, R3, R4, and R5 are each independently selected from H, halogen, a C1-C12 straight or branched alkyl, a C3-C8 cycloalkyl, a C6-C15 aryl, or arylalkyl. The present invention can provide a catalyst showing high polymerization reaction activity and excellent stereospecificity, by applying a novel type of internal electron donor.

A solid catalyst component for the polymerization of olefins comprises Mg, Ti and an electron donor of formula (I) wherein R1 and R9 groups, equal to or different from each other, are selected from C1-C15 hydrocarbyl groups, R2 groups are selected from hydrogen or C1-C10 hydrocarbyl groups, R3 to R8 groups are independently selected from hydrogen or C1-C15 hydrocarbyl groups, which groups can be fused together to form one or more rings. A catalyst system based on the solid catalyst component has high activity and stereospecificity.

A solid catalyst component for olefin polymerization comprises magnesium halide, a titanium compound having at least a Ti-halogen bond, and at least two electron donor compounds, one of which is selected from a specific class of 1,3-diethers, and the other of which is selected from diether organic compounds. The solid catalyst component exhibits high polymerization activity and stereospecificity even in the absence of an external donor.

The invention relates to the field of chemical synthesis, and discloses a method for constructing a full-alkyl quaternary carbon stereocenter through stereospecific conversion of chiral tertiary alcohol. The method successfully solves the industrial problem that the peralkyl quaternary carbon center is difficult to construct with high stereoselectivity due to huge steric hindrance and lack of electron difference, the process shows excellent stereospecificity and chemical selectivity, the ee value of the product is as high as 98%, the dr value is superior to 20: 1, and meanwhile, the excellent yield of 90% or above is kept; besides, according to the scheme, the substrate is wide in universality and can be compatible with various chemical small molecule substrates of different structures, the used reagents such as triethyl aluminum and KHMDS are cheap and easy to obtain, operation is easy and convenient, and a simple and efficient stereospecific conversion strategy with industrial application potential is provided for synthesis of complex drug intermediates.

A solid catalyst component for the polymerization of olefins, which comprises a magnesium halide, a titanium compound having at least Ti-halogen bonds and at least two electron donor compounds, one electron donor compound being selected from a specific class of 1,3-diethers and the other electron donor compound being selected from diether organic compounds, the solid catalyst component having high polymerization activity and stereospecificity even in the absence of an external donor.

The invention relates to the technical field of preparation of circularly polarized light-emitting materials, in particular to a spiral chiral four-tooth ring metal platinum (II) and / or palladium (II) complex circularly polarized light-emitting material and application. According to the formation of the spiral chiral metal complex molecule, the whole tetradentate ligand can be autonomously induced to coordinate with metal ions in a small steric hindrance mode through a central chiral fragment in the ligand, an optically pure spiral chiral metal complex circularly polarized light luminescent material is formed, and the induced reaction has stereospecificity; the spiral chiral metal complex does not need chiral resolution. The spiral chiral metal complex has important application in circular polarization light-emitting elements and related fields.

The invention belongs to the technical field of organic synthesis, and particularly discloses a metal phthalocyanine polymer catalyst and a preparation method and application thereof.The preparation method comprises the steps that a proper amount of metal phthalocyanine, a phenyl skeleton and a cross-linking agent are mixed in a solvent and stirred to be uniform, then a Lewis acid catalyst is added, heating and stirring are conducted, the temperature is increased to reflux for a reaction, and the metal phthalocyanine polymer catalyst is obtained; after the reaction is finished, filtering, washing and drying in vacuum to obtain a metal phthalocyanine polymer catalyst marked as POL-MPc; the POL-MPc prepared by the invention is used for catalyzing the hydration of methoxy dihydromyrcene to obtain sandalwood ether, and the reaction has high stereospecificity; and the catalyst is easy to separate and recover, can be recycled for multiple times, has no obvious loss of catalytic activity, and has industrial value.

The application provides a base-promoted system for synthesizing alkenyl borate from propargyl alcohol compounds, which comprises propargyl alcohol compounds, a diboron reagent, a base and a solvent. The application also provides an application of the base-promoted system, which is used for synthesizing alkenyl borate from propargyl alcohol compounds through a borohydride reaction. The method is as follows: under the action of a base and a solvent, a borohydride reaction of propargyl alcohol compounds is promoted by using a diboron reagent as a boron source, so as to synthesize alkenyl borate in a trans stereospecific and beta-regioselective manner. In the reaction system, the trans stereospecific and beta-regioselectivity of the borohydride addition of propargyl alcohol compounds are realized, and a transition metal catalyst is not needed, and the system has the advantages of wide substrate application range, high conversion rate and mild reaction conditions.

The application belongs to the field of catalysts, and discloses a catalyst component for olefin polymerization, a catalyst for olefin polymerization and application of the catalyst. The synthesis raw material of the catalyst carrier for olefin polymerization in the catalyst component for olefin polymerization comprises elemental sulfur, a bismuth source compound, a magnesium halide with a general formula of MgXY, a compound with a general formula of ROH and an oxirane compound; in the general formula MgXY, X is halogen, Y is halogen, C1-C 14 alkyl, C1-C 14 alkoxy, C6-C 14 aryl or C6-C 14 aryloxy; in the general formula ROH, R is C1-C8 linear alkyl, C3-C8 branched alkyl or C3-C8 cycloalkyl; the structure of the oxirane compound is shown in formula (II): wherein R5 and R6 are each independently hydrogen, C1-C5 linear alkyl or C3-C5 branched alkyl, wherein the hydrogen in the alkyl is optionally substituted by a halogen atom; when the catalyst component for olefin polymerization prepared by the application is used for propylene polymerization, the stereospecificity of the catalyst is better, and the catalyst has great industrial application prospect.

The invention discloses an internal electron donor compound which has a structure as shown in a formula I. A catalyst containing the internal electron donor compound can be used for preparing a catalyst with high polymerization reaction activity and excellent stereospecificity. Compared with diacetic acid-1, 8-naphthol ester prepared from naphthalene diphenol, the compound prepared from naphthalene dimethanol is more stable in structure, high in polymerization activity and higher in polymer isotacticity.

The application provides a spherical catalyst component for olefin polymerization and a preparation method, a catalyst system and application thereof, and belongs to the technical field of olefin polymerization.The spherical catalyst component comprises a spherical solid and a long-chain alpha-olefin compound shown as CH2=CHR a wherein R a is selected from linear or branched alkyl with 14-30 carbon atoms, and cycloalkyl with 14-30 carbon atoms; and the spherical solid comprises magnesium elements, titanium elements, halogen and an internal electron donor compound.The application uses the long-chain alpha-olefin compound to treat the spherical solid, so that the catalyst component has higher activity and stereospecificity, the obtained polymer powder has higher sphericity and bulk density, the powder D 10 is larger, the fine particles are reduced, the particle size distribution is narrower, and the phenomenon of cracking, breaking and opening is almost eliminated, and the application is suitable for industrial device operation.

The present invention relates to stereoisomeric phosphatidyl oligoglycerols having a predetermined configuration in at least three stereocenters, in particular to phosphatidyl oligoglycerols as a single stereoisomer. The present invention also relates to a stereospecific method for providing a stereospecific phosphatidyl oligoglycerol having a predetermined configuration in at least three stereocenters, in particular for providing a phosphatidyl oligoglycerol as a single stereoisomer, and to a liposome comprising the novel stereoisomeric phosphatidyl oligoglycerol, in particular, liposomes comprising novel stereoisomeric phosphatidyl oligoglycerols as a single stereoisomer.

The application belongs to the technical field of compound preparation, and particularly relates to an alpha-alkylidene lactone compound and a method for preparing the alpha-alkylidene lactone compound from a cyclopropenone derivative. The method comprises the following steps: first, synthesizing a substrate cyclopropenone derivative; then, stirring the cyclopropenone derivative, AgBF4 and ethylene glycol dimethyl ether in a Shrek bottle at 80 DEG C; and finally, concentrating and purifying the mixture by column chromatography to obtain the alpha-alkylidene lactone compound. The previous synthesis method can only be applied to the synthesis of one or several types of alpha-alkylidene lactone compounds, while the method can realize the synthesis of alpha-alkylidene-beta-lactone, alpha-alkylidene-gamma-lactone, alpha-alkylidene-delta-lactone and alpha-alkylidene-epsilon-lactone compounds, and has good universality. The method has stereo-specificity in the synthesis of alpha-alkylidene lactone compounds. The method uses a cheap catalyst, has high reaction yield, and is convenient to prepare the substrate, and has good applicability.

This invention belongs to the field of olefin polymerization technology, and relates to a solid catalyst component for olefin polymerization, its preparation method, the catalyst, and its application. The catalyst component comprises the reaction products of the following components: a magnesium source, a titanium source, and an internal electron donor; the internal electron donor comprises succinic acid monoester compounds, glycol ester compounds, and diether compounds. The preparation method includes the following steps: contacting a magnesium source with a titanium source, adding an internal electron donor before, during, and after the contacting reaction, then treating with the titanium source once or multiple times, and finally washing with an inert solvent to obtain the solid catalyst component. This invention uses an internal electron donor comprising succinic acid monoester compounds, glycol ester compounds, and diether compounds; the catalyst is a non-plasticizing catalyst; and it features stable release of polymerization activity, high stereospecificity, and high activity.

This paper discloses a method for preparing α‑ Chiral amidine method. Through the in situ preparation of chiral allylamine and alkenylimine, the asymmetric N‑ The heterogeneous Claisen rearrangement method was successfully constructed α‑ Chiral amidine. The reaction has the following advantages: (1) The reaction conditions are very mild, the reaction can be carried out at room temperature, and no equivalent strong base is required, which is more environmentally friendly. (2) The one-pot two-step method can eliminate the intermediate processing steps for making chiral substrates, saving manpower and material resources and reducing consumption. (3) It can simultaneously construct the chiral center and the amidine functional group, with atom economy and step economy. (4) The reaction yield is high, and the template product can be obtained with a total yield of 94% in two steps. The chirality of allylamine can also be stereospecifically transferred to the amidine, and the template product has 95% of (5) The substrate universality and functional group tolerance are good, such as cyano, tert-butyl, ester, methoxy, nitro, and trifluoromethyl groups can all react, both ortho- and di-substitutions are active, and heteroaromatic compounds can also obtain the target product.

Provided are a spiro chiral tetradentate cyclometalated platinum (II) and / or palladium (II) complex circularly polarized luminescence material and the use thereof. For the formation of the spiro chiral metal complex molecule, a central chiral fragment in a ligand can autonomously induce the coordination of the entire tetradentate ligand with metal ions in a small steric hindrance manner, so as to form an optically-pure spiro chiral metal complex circularly polarized luminescence material. The induced reaction has stereospecificity, such that the spiro chiral metal complex does not require chiral resolution. The spiro chiral metal complex has significant application value in circularly polarized luminescence elements and related fields.

The present application belongs to the technical field of olefin polymerization catalysts, and relates to an olefin polymerization method. The olefin polymerization method comprises the following steps: allowing a mixture of an olefin and an alcohol compound to react with a catalyst system; wherein the catalyst system comprises the reaction product of the following components: (1) a solid catalyst component comprising titanium, magnesium, halogen and an internal electron donor compound; the magnesium compound is a dialkoxymagnesium; (2) an alkyl aluminum compound; and (3) an external electron donor compound. The alcohol compound introduced by the catalyst system in the polymerization process improves the stereospecificity of the catalyst, and the polymerization activity and hydrogen sensitivity are basically unchanged, which is beneficial to the production of high-performance polymer products while maintaining good comprehensive performance of the catalyst.

The application discloses a short-chain dehydrogenase, an engineering bacterium and application of the short-chain dehydrogenase in asymmetric reduction of a latent chiral carbonyl compound. The application screens a short-chain dehydrogenase with high activity and strong stereospecificity, has a wide substrate spectrum, is easy to operate and has mild reaction conditions. The produced chiral alcohol has a good application prospect in chiral drug intermediates and creation of a high-selectivity catalyst, and solves the problems of low conversion rate, low yield, low e.e. value, complex reaction process and many by-products in traditional chemical methods. The short-chain dehydrogenase has good tolerance to isopropyl alcohol, can realize coenzyme circulation by taking isopropyl alcohol as a hydrogen source, and can directly utilize intracellular coenzyme when adopting whole cells as a catalyst, so that zero addition of coenzyme is realized. In addition, the by-product acetone produced in the enzyme catalysis reaction and the residual isopropyl alcohol can be separated and recovered through conventional technical means, so that the production cost is greatly reduced.

The invention discloses a method for coupling polypeptide or protein and oligonucleotide promoted by visible light, which comprises the following steps: taking polypeptide or protein at least containing one free and solvent-exposed cysteine as a raw material, and oligonucleotide or 6-aza-uracil derivative containing 6-aza-uracil nucleoside as another raw material; a pyridinium salt is used as an activating reagent, a buffer solution is used as a reaction solvent, and polypeptide or protein and oligonucleotide are coupled to form a stereoscopically retained stable C-C bond under the participation of an additive and the irradiation of visible light. The configuration of the conjugate obtained by the invention at a modification site is maintained. Meanwhile, the method has excellent site selectivity, accurate modification of polypeptide or protein can be realized, the reaction is carried out under a biocompatible condition, a catalyst or a reducing agent does not need to be added, the reaction efficiency is high, biocompatibility is realized, and disulfide bonds in the polypeptide or the protein can be compatible.

The invention relates to the technical field of medical chemical medicines, in particular to a novel synthesis method of cis-chiral alpha-hydroxy-beta-amino acid hydrochloride. The preparation method comprises the following steps: taking cheap and easily available natural alpha-amino acid as a starting raw material, firstly, preparing N-Boc protected amino aldehyde 2 from the natural alpha-amino acid as the starting raw material, then carrying out Grignard reaction on the N-Boc protected amino aldehyde 2 and vinyl magnesium bromide at low temperature to obtain corresponding o-amino alcohol, then reacting the o-amino alcohol with 2, 2-dimethoxypropane at 0 DEG C under the catalytic action of p-toluenesulfonic acid, and finally obtaining the N-Boc protected amino aldehyde 2. And performing stereospecific ring closing to obtain trans-oxazolidine 3. The compound 3 is subjected to Upjohn dihydroxylation reaction and sodium periodate oxidation to obtain corresponding aldehyde, and then the aldehyde is oxidized by potassium permanganate under a weak acidic condition to obtain corresponding carboxylic acid 4. And finally, carrying out reflux deprotection by using 6N hydrochloric acid to obtain the cis-chiral alpha-hydroxyl-beta-amino acid hydrochloride. The synthetic route is convenient to operate, the total yield is high, and large-scale preparation can be achieved.

The invention relates to the technical field of polymer synthesis, and discloses a chiral zinc-based catalyst and a preparation method and application thereof.The preparation method comprises the steps that a phenylenediamine derivative and a halogenated carboxylic acid compound are taken to react, and a halogenated benzimidazole derivative is obtained; carrying out nucleophilic substitution reaction on the halogenated benzimidazole derivative and an aminophenol compound in an organic solvent to obtain a tridentate ligand; the tridentate ligand and a zinc source compound are subjected to a complexation reaction in an organic solvent to obtain the chiral zinc-based catalyst. The chiral zinc-based catalyst has a tridentate chiral active center with an adjustable coordination environment, and can induce the monomer to be inserted in a specific stereoregularity mode in the ring-opening polymerization process of the lactone monomer, so that the stereoregularity of the polyhydroxyalkanoate is improved; according to the invention, on the premise of ensuring high monomer conversion rate, collaborative regulation of polymer molecular weight and molecular weight distribution is realized, and preparation of polyhydroxyalkanoate with high molecular weight, narrow molecular weight distribution and high stereoregularity is facilitated.

The application provides a propylene polymerization spherical catalyst component, a solid titanium main catalyst and a preparation method and application thereof. The solid titanium main catalyst comprises titanium halide, magnesium halide and peroxobenzoic acid ester internal electron donor. Under the action of an alkyl aluminum cocatalyst and an organic silicon compound external electron donor, the catalyst is used for propylene polymerization or copolymerization, shows very high polymerization activity, very good hydrogen regulation sensitivity and stereospecificity, can manufacture green and environment-friendly propylene polymers with high isotacticity, good particle morphology and few fine powders, and can be used for producing high melt index polypropylene products.

The invention relates to the technical field of chemical raw material medicine manufacturing, in particular to a phosphonamide compound with a pentavalent phosphorus chiral center and a one-pot synthesis method of the phosphonamide compound. The structural formula of the compound is shown as (V). The synthesis method comprises the following steps: by taking chiral bicyclic imidazole as a catalyst, carrying out enantioselective amino substitution reaction on a phosphonic dichloride raw material (I) and a secondary amine reactant (II) to obtain a chiral aminophosphoryl chloride intermediate (III), and carrying out stereospecific nucleophilic substitution on the chiral aminophosphoryl chloride intermediate (III) and a nucleophilic reagent (IV) to obtain a chiral phosphoramide product (V). By adopting the method, the substrate adaptability is wide, the enantioselectivity is excellent, the product derivatization is strong, and a universal platform is provided for efficient synthesis of phosphorus chiral bioactive molecules.

A solid catalyst component for olefin polymerization, comprising Mg, Ti, and an electron donor of formula (I): 【Chemical 1】 JPEG2026513612000006.jpg3837 (I) In the formula, R 1 and R 5 groups are either equal to or different from each other and are selected from C1-C 15 hydrocarbon groups, R 2 group is selected from C2-C 10 hydrocarbon groups, R 3 is hydrogen or a C1-C 20 hydrocarbon group, and R 4 is selected from C7-C 20 halogen-substituted aryl groups. The catalyst system based on the solid catalyst component has high activity and stereospecificity.

The application provides a non-classical C-glycoside and a stereospecific synthesis method and application thereof, and the synthesis method comprises the following steps: taking a non-classical sugar-based stannane as a nucleophilic reagent, taking a halogenated hydrocarbon as an electrophilic reagent, and performing a Stille cross-coupling reaction to obtain the non-classical C-glycoside. The non-classical C-glycoside and the stereospecific synthesis method and application thereof provided by the application have the advantages that the synthesis method is simple in process, convenient in operation, high in yield, good in functional group tolerance, strong in stereospecificity, wide in sugar substrate range, and compatible with unprotected sugar and an aqueous phase system; furthermore, the obtained non-classical C-glycoside not only has better antibacterial activity, but also can be used as an active pharmaceutical material, and promotes the technological progress of the pharmaceutical synthesis industry and the pharmaceutical industry.