44 results about "Stereospecificity" patented technology

The present invention relates to a solid catalyst component for olefin polymerization, a catalyst for olefin polymerization, and a method for producing an olefin polymer. Provided are a method for producing a solid catalyst component for olefin polymerization, a method for producing a catalyst for olefin polymerization, and a method for producing an olefin polymer, which have excellent polymerization activity and can produce a polymer with excellent stereospecificity. Provided is a method for producing a solid catalyst component for olefin polymerization, the method comprising contacting a magnesium compound and a specific styrene-based compound with each other to obtain a pre-contact product, and then contacting the pre-contact product, a titanium halide compound, and an internal electron donor compound with each other to obtain a solid catalyst component for olefin polymerization; and a method for producing a catalyst for olefin polymerization and a method for producing an olefin polymer using the solid catalyst component for olefin polymerization obtained by this production method.

The invention discloses a solid catalyst for olefin polymerization, which comprises succinic acid ester with double bonds in a general formula (I) as an internal electron donor, and due to the unique space and electron effects, the catalyst containing the succinic acid ester has better activity, stereospecificity and hydrogen regulation sensitivity in propylene (co) polymerization, and the molecular weight distribution of a polymer is wide. And the method is suitable for development of polymer products with different marks. # imgabs0 #

A solid catalyst component for the polymerization of olefins comprising a magnesium halide, a titanium compound having at least a Ti-halogen bond and at least and at least two electron donor compounds one being selected from a specific class of 1,3-diethers and the other from diester organic compounds are endowed with high polymerization activity and stereospecificity even in the absence of external donors.

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.

The invention provides a propylene polymerization sphere-like catalyst component, a solid titanium main catalyst and a preparation method and application of the solid titanium main catalyst, the solid titanium main catalyst comprises titanium halide, magnesium halide and peroxidated benzoate internal electron donors, and under the action of an alkyl aluminum cocatalyst and an organosilicon compound external electron donor, the solid titanium main catalyst is prepared into the sphere-like catalyst component. The catalyst is used for propylene polymerization or copolymerization, shows very high polymerization activity, very good hydrogen regulation sensitivity and stereospecificity, can be used for preparing a green and environment-friendly propylene polymer with high polymer isotacticity, good particle morphology and less fine powder, and can be used for producing a polypropylene product with a high melt index.

The invention discloses a method for stereospecifically synthesizing a Tn antigen and a TF antigen, and belongs to the technical field of synthesis of the Tn antigen and the TF antigen, and the specific method comprises the following steps: taking 2-azido-2-deoxy-3-O-tertiary butyl dimethyl silyl-4, 6-di-O-benzoyl-galactosyl phenyl thioester as a donor, taking serine as a receptor, and carrying out a one-pot reaction to obtain the Tn antigen and the TF antigen. Adopting a remote adjacent group to participate in effect stereospecificity to synthesize a protected Tn antigen; selectively removing tert-butyldimethylsilyl of the Tn antigen to dissociate 3-site hydroxyl, and reacting with peracetylated galactosyl trichloroacetimidate to obtain a protected TF antigen; and finally, removing protecting groups for protecting the Tn antigen and the TF antigen to obtain the Tn antigen and the TF antigen. The synthesis method has the advantages of mild conditions, low cost, high yield and the like, and meanwhile, the remote participation effect can be enhanced, and the stereospecificity can be efficiently realized.

The invention provides a maleate compound and a preparation method and application thereof in olefin catalytic polymerization, an olefin polymerization catalytic component in the application comprises a magnesium source, a titanium source, halogen and an internal electron donor, and the internal electron donor is the maleate compound with a bicyclic structure as shown in a general formula I. Due to the unique space and electron effects of the maleate compound, the catalyst containing the maleate has better activity, stereospecificity and hydrogen regulation sensitivity in propylene (co) polymerization, and the molecular weight distribution of the polymer is wide. # imgabs0 #

A solid catalyst component for the polymerization of olefins comprising a magnesium halide, a titanium compound having at least a Ti-halogen bond and at least and at least two electron donor compounds one being selected from a specific class of 1,3-diethers and the other from diester organic compounds are endowed with high polymerization activity and stereospecificity even in the absence of external donors.

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.

The invention provides a catalyst component for olefin polymerization, a catalyst and application thereof, and belongs to the technical field of olefin polymerization. The catalyst component contains a product obtained by reaction of a magnesium source, a titanium source and an internal electron donor, and the internal electron donor contains a furan compound and a diether compound. The catalyst disclosed by the invention has high hydrogen regulation sensitivity and stereospecificity, the balance between the hydrogen regulation sensitivity and the stereospecificity is good, and the molecular weight distribution of the prepared low-melt-index polymer is wider than that of a high-melt-index polymer; the components of the catalyst provided by the invention do not contain phthalate compounds (plasticizers).

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 belongs to the field of organic synthesis, and relates to a polysubstituted cyclobutanol compound as well as preparation and application thereof. In a dry Schracker reaction tube, 2-alkynyl benzaldoxime and bicyclo [1.1. 0] butane are used as raw materials and react in a catalyst and a solvent to synthesize the compound. A silver (I) catalysis method is creatively applied, and the advantages are remarkable. The method has the advantages of mild reaction conditions, cheap catalyst, low energy consumption, small pollution and good functional group compatibility. The method provides an efficient and mild path for complex cyclobutanol synthesis, the substrate application is wide, the stereospecificity is high, and the tolerance to various functional groups is good. The product can also participate in the synthesis of other compounds, and the high efficiency and amplification experiment in reactants containing bioactive groups fully shows the wide application potential in the fields of synthetic chemistry and medicinal chemistry.

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.

This present invention relates to a method for using halogenation agents to react with magnesium precursor or with magnesium complexes to form catalyst components without using internal electron donors. The catalyst components are used to produce polypropylene with good productivity and high stereospecificity. This method offers a wide range of catalyst component preparations and selections to enhance the catalyst component applications regarding activity, stereospecificity, hydrogen response, molecular weight, and distributions.

A solid catalyst component for olefin polymerization includes a magnesium halide, a titanium compound having at least one Ti-halogen bond, and at least one 1, 3-diether of a specific formula, the solid catalyst component having high polymerization activity and stereospecificity even in the absence of an external donor.

The invention relates to a catalyst for olefin polymerization, which specifically comprises the following components in percentage by weight: (a) a catalytic component containing 10-25% of magnesium, 1-10% of titanium, 40-60% of halogen and 1-30% of at least one heteroatom-containing ortho-ester selected from a general formula (I); (b) an aluminum alkyl compound; (c) optionally, an external electron donor; as a compound with a special electronic structure is adopted as an internal electron donor, the synthesized Ziegler-Natta catalyst shows very high catalytic activity in propylene (co) polymerization, and the obtained polymer has high stereospecificity. # imgabs0 #

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 invention relates to a solid Ziegler-Natta catalyst which specifically comprises the following components in percentage by weight: (a) a catalytic component containing 10-25% of magnesium, 1-10% of titanium, 40-60% of halogen and 1-30% of at least one maleate selected from a general formula (I); (b) an aluminum alkyl compound; (c) optionally, an external electron donor; as the compound which has a special structure and contains a thiophene structure is used as an internal electron donor, the synthesized Ziegler-Natta catalyst shows very high catalytic activity in propylene (co) polymerization, and the obtained polymer has high stereospecificity. # imgabs0 #

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 invention belongs to the technical field of olefin polymerization, and relates to a solid catalyst component for olefin polymerization, and a preparation method, a catalyst and application thereof. The catalyst component comprises reaction products of the following components: a magnesium source, a titanium source and an internal electron donor, wherein the internal electron donor comprises a succinic acid monoester compound. The preparation method comprises the following steps: carrying out a contact reaction on a magnesium source and a titanium source, adding an internal electron donor in one or more time periods before, during and after the contact reaction of the magnesium source and the titanium source, then carrying out one or more times of treatment by adopting the titanium source, and then washing by using an inert solvent to obtain the solid catalyst component. According to the invention, the succinic acid monoester compound is used as an internal electron donor, and the catalyst has significantly low stereospecificity, good hydrogen regulation sensitivity and polymerization activity, and can be used for preparing low-isotacticity polypropylene.

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.

The invention discloses short-chain dehydrogenase, engineering bacteria and application of the short-chain dehydrogenase in asymmetric reduction of prochiral carbonyl compounds, the short-chain dehydrogenase with high activity and strong stereospecificity is obtained through screening, and the short-chain dehydrogenase has the advantages of wide substrate spectrum, mild reaction conditions, simplicity and convenience in operation, high yield and high yield. The produced chiral alcohol has a good application prospect in the creation of chiral drug intermediates and high-selectivity catalysts, and solves the problems of low conversion rate, low yield, low e.e. Value, complex reaction process, many byproducts and the like in the traditional chemical method. The short-chain dehydrogenase provided by the invention has good tolerance to isopropanol, can realize circulation of coenzyme by taking isopropanol as a hydrogen source, and can directly utilize intracellular coenzyme when whole cells are taken as a catalyst, thereby realizing zero addition of coenzyme. In addition, a by-product acetone generated by the enzyme catalytic reaction and isopropanol remaining in the reaction can be separated and recycled through a conventional technical means, so that the production cost is greatly reduced.

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.