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CN-121991138-A - Titanium metallocene compound with limited geometric configuration and preparation method and application thereof

CN121991138ACN 121991138 ACN121991138 ACN 121991138ACN-121991138-A

Abstract

The invention discloses a geometry-limiting titanium metallocene compound, a preparation method and application thereof, wherein the geometry-limiting titanium metallocene compound is a compound with a general formula (I): Wherein R 1 、R 2 、R 3 、R 4 are the same or different and are each independently selected from alkyl, R is selected from one of fluoro, methoxy, methyl, tertiary butyl and H, and n is 1 or 0. The geometry-limiting titanium metallocene compound has better catalytic activity, and the prepared polypropylene has high melt index and good fluidity. The constrained geometry titanocene compound of the invention is synthesized by different amine groups, completes the optimization of the whole synthesis route, comprises the problem of monosubstituted in the silicon bridging reaction, and has higher yield in the whole process. The invention has the advantages of easily available raw materials, low cost and easy realization of technological production.

Inventors

  • LEI JUNYU
  • LIN LONG
  • WANG KEFENG
  • XU QIANG
  • YANG TONG
  • ZHANG WEI
  • CHEN SHANGTAO
  • HAO HAIJUN
  • JIA YUSEN

Assignees

  • 中国石油天然气股份有限公司

Dates

Publication Date
20260508
Application Date
20241107

Claims (11)

  1. 1. A constrained geometry titanocene compound characterized by the fact that it is a compound having the general formula (I): Wherein, the R 1 、R 2 、R 3 、R 4 , which are identical or different, are each independently selected from alkyl; r is selected from one of fluoro, methoxy, methyl, tertiary butyl and H; n is 1 or 0.
  2. 2. A method for preparing a constrained geometry titanocene compound comprising: (1) Adding a compound shown in a general formula (VII) under a nitrogen atmosphere, adding n-butyllithium, adding a compound shown in a general formula (VIII), stirring, and reacting to obtain a ligand precursor shown in a general formula (IX); Wherein, the R is selected from one of fluoro, methoxy, methyl, tertiary butyl and H, R 1 、R 2 、R 3 、R 4 are the same or different and are each independently selected from alkyl, n is 1 or 0; (2) Adding a ligand precursor shown in a general formula (IX) into a solvent according to a fifth formula, adding n-butyllithium under the conditions of an alcohol liquid nitrogen bath and nitrogen protection, adding a titanium tetrachloride complex under the condition of low temperature, and reacting to obtain a compound shown in the general formula (I); Wherein, the R is selected from one of fluoro, methoxy, methyl, tertiary butyl and H, R 1 、R 2 、R 3 、R 4 is the same or different and is independently selected from alkyl, and n is 1 or 0.
  3. 3. The constrained geometry metallocene compound of claim 1 or the method of preparation of claim 2, wherein the alkyl is selected from C1-C12 linear or branched alkyl.
  4. 4. The production method according to claim 2, wherein when n is 1 in the compound represented by the general formula (VIII), the production method of the compound represented by the general formula (VIII) comprises the steps of: (1-1-1) reacting a ketone compound represented by the general formula (II) with a formative reagent according to the formula I to obtain a compound represented by the general formula (III); Wherein, the R is one of fluoro, methoxy, methyl, tertiary butyl and H; R' is methyl or methoxy; X is halogen; (1-1-2) mixing acetonitrile with a compound shown in a general formula (III) according to a second formula, dropwise adding concentrated sulfuric acid, and reacting to obtain a compound shown in a general formula (IV); wherein R is one of fluoro, methoxy, methyl, tert-butyl and H; (1-1-3) reacting a compound represented by the general formula (IV) to obtain a compound represented by the general formula (VIII).
  5. 5. The method according to claim 4, wherein the reaction temperature is 0 to 20℃and the reaction time is 3 to 8 hours in (1-1-1), and the formative reagent is at least one selected from the group consisting of methyl magnesium chloride and methyl magnesium bromide.
  6. 6. The production method according to claim 2, wherein when n is 0 in the compound represented by the general formula (VIII), the compound represented by the general formula (VIII) is a compound represented by the general formula (VI), the production method of the compound represented by the general formula (VIII) comprises the steps of: (1-2) dissolving a compound shown in a general formula (V) in a polar solvent according to a third formula, adding anhydrous cerium chloride and methyl lithium diethyl ether solution, and reacting to obtain a compound shown in a general formula (VI); wherein R is one of fluoro, methoxy, methyl, tert-butyl and H.
  7. 7. The process according to claim 6, wherein in (1-2), the reaction is carried out at a temperature of-80 to 60℃for a period of 10 to 15 hours, the pH is adjusted by using an alkali metal hydroxide, the polar solvent is an ether solvent, and the reaction is quenched with concentrated aqueous ammonia.
  8. 8. The method according to claim 2, wherein in (2), the solvent is at least one of an anhydrous diethyl ether solution, n-hexane, toluene, and tetrahydrofuran, the reaction temperature is-40 to 0 ℃, and the reaction time is 20 to 40 hours.
  9. 9. Use of a constrained geometry titanocene compound of claim 1 or obtained by the method of preparation of any one of claims 2 to 8 as a propylene polymerization catalyst.
  10. 10. A propylene polymerization catalyst comprising the constrained geometry titanocene compound of claim 1 or the constrained geometry titanocene compound obtained by the process of any one of claims 2-8.
  11. 11. A polypropylene catalyzed polymerization reaction characterized in that the reaction employs the constrained geometry titanocene compound of claim 1 or the constrained geometry titanocene compound obtained by the method of preparation of any one of claims 2-8 as a propylene polymerization catalyst.

Description

Titanium metallocene compound with limited geometric configuration and preparation method and application thereof Technical Field The invention belongs to the technical field of olefin polymerization, and relates to a titanium metallocene compound with limited geometric configuration, a preparation method and application thereof. Background The polypropylene material is a material with excellent performance, is widely applied to the aspects of clothing, daily necessities, medical and health, food industry and the like, and along with the continuous improvement of the processing technology, the catalyst required for producing polypropylene is also more and more severely required. At the beginning of the eighties of the twentieth century, sinn (Angew.chem.int.ed.Engl., 1980,92,396) and Kaminsky (macromol.chem., rapid Commun.,1983,4,417) et al have found that a homogeneous catalytic olefin polymerization system composed of a metallocene complex and MAO can catalyze olefin polymerization with high activity. The discovery of methylaluminoxane has prompted rapid advances in this area. Metallocene and other transition metal complexes activated by methylaluminoxane are more than 10 times more active than Ziegler-Natta catalysts and have the feature of a polymer molecular weight distribution and a polymer tacticity that is adjustable (chem. Rev.,2000, 100:1253). The limited geometry catalyst (C 5Me4SiMe2NtBu)TiCl2 (CGC catalyst) is one of the few metallocene catalysts which are industrially applied and can catalyze ethylene/alpha-olefin to obtain a high-end polyolefin product POE elastomer, the POE brand in the market of China is the same as that of foreign catalyst companies, and the POE elastomer is seriously dependent on foreign import. Nabika EP0908435 Al 12.10.1998 was synthesized from tert-butylamine without modification of the amine groups. Stevens J C EP416815A2[ P ] 1991-03-13, sodium hydride is used, and ether solvent is diethyl ether. However, the technology has the defects of (1) high risk coefficient, increased risk hidden trouble existing in the amplifying production process, and (2) increased production cost due to the fact that 3 times of dimethyl chlorosilane and tert-butylamine are used for sodium hydride. Disclosure of Invention The invention aims to provide a novel constrained geometry titanocene compound, and a preparation method and application thereof. To achieve the above object, the present invention provides a constrained geometry titanocene compound which is a compound having the general formula (I): Wherein, the R 1、R2、R3、R4, which are identical or different, are each independently selected from alkyl; r is selected from one of fluoro, methoxy, methyl, tertiary butyl and H; n is 1 or 0. In at least one possible embodiment, the alkyl group is selected from C1-C12 straight or branched alkyl groups. The invention also provides a preparation method of the geometry-limiting metallocene compound, which comprises the following steps: (1) Adding a compound shown in a general formula (VII) under a nitrogen atmosphere, adding n-butyllithium, adding a compound shown in a general formula (VIII), stirring, and reacting to obtain a ligand precursor shown in a general formula (IX); Wherein, the R is selected from one of fluoro, methoxy, methyl, tertiary butyl and H, R 1、R2、R3、R4 are the same or different and are each independently selected from alkyl, n is 1 or 0; (2) Adding a ligand precursor shown in a general formula (IX) into a solvent according to a fifth formula, adding n-butyllithium under the conditions of an alcohol liquid nitrogen bath and nitrogen protection, adding a titanium tetrachloride complex under the condition of low temperature, and reacting to obtain a compound shown in the general formula (I); Wherein, the R is selected from one of fluoro, methoxy, methyl, tertiary butyl and H, R 1、R2、R3、R4 is the same or different and is independently selected from alkyl, and n is 1 or 0. In at least one possible embodiment, the alkyl group is selected from C1-C12 straight or branched alkyl groups. In at least one possible embodiment, when n=1 in the compound represented by the general formula (VIII), the method for preparing the compound represented by the general formula (VIII) includes the steps of: (1-1-1) reacting a ketone compound represented by the general formula (II) with a formative reagent according to the formula I to obtain a compound represented by the general formula (III); Wherein, the R is one of fluoro, methoxy, methyl, tertiary butyl and H; R' is methyl or methoxy; X is halogen; (1-1-2) mixing acetonitrile with a compound shown in a general formula (III) according to a second formula, dropwise adding concentrated sulfuric acid, and reacting to obtain a compound shown in a general formula (IV); wherein R is one of fluoro, methoxy, methyl, tert-butyl and H; (1-1-3) reacting a compound represented by the general formula (IV) to obtain a compound represented by the general formula (