RU2439045C1 - Method of producing highly branched propylene trimers - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing highly branched propylene trimers (2,6-dimethylheptene-3, 2,6-dimethylheptene-2, 4,6-dimethylheptene-3, 2-methyloctene-2, 7-methyloctene-3) in a heterogeneous catalyst system containing silicon oxides, characterised by that the catalyst used is bis-allyl nickel Ni(C₃H₅)₂, which is deposited on silicious leaves of diatomic algae with specific surface area ranging from 20 to 165 m²/g; catalytic trimerisation of propylene takes place in a toluene medium while actively stirring the catalyst suspension in toluene in a propylene atmosphere, wherein content of nickel in the catalyst is equal to 0.4-10.5 wt %; the reaction takes place at temperature 20-25°C and atmospheric pressure.

EFFECT: high output of the desired product with considerably affordable method of producing said product.

5 cl, 4 ex, 1 tbl

Description

The invention relates to a method for the catalytic trimerization of propylene into highly branched olefins (2,6-dimethylheptene-3, 2,6-dimethylheptene-2, 4,6-dimethylheptene-3, 2-methyloctene-2, 7-methyloctene-3), which are widely demanded in the production of polymers with desired properties as a copolymerizable monomer. These products can be used in the manufacture of plasticizers for plastics based on PVC, as reagents in the production of alkylated aromatic compounds used as high-temperature organic coolants [US Pat. RU 2101270 C1 Russian Federation, IPC. A method of producing alkylaromatic compounds / Margulis M.A., Vasilchenko S.V., Porollo V.A. Claim 04/11/1996. Publ. 01/10/1998.] [1], as well as in the production of fatty acids, which are in demand in the synthetic detergent industry, for the production of additives to high-quality motor oils. They are the starting materials in a number of fine organic syntheses in the pharmaceutical industry [David J. Cole-Hamilton. Catalyst Separation, Recovery, and Recycling. Science. - 2003. - V 299. - P.1702-1706] [2].

Demand for branched olefins is growing, especially with the development of the production of plastics with specific properties to meet the needs of such current technologies as prosthetics, metal substitution for plastic in the aviation, automotive and military industries. Analysis of the scientific and technical literature showed that today there are practically no available methods for the synthesis of branched C ₉ olefins.

Known methods for producing highly branched trimers of propylene (2,6-dimethylheptene-3, 2,6-dimethylheptene-2, 4,6-dimethylheptene-3, 2-methyl-octene-2, 7-methyl-octene-3) by various complex methods of classical chemistry, such as the restoration of acetals [Ehud Keinan, Noam Greenspoon. Highly Chemoselective Reductions with PMHS and Palladium (0) Catalyst // J. Org. Chem. - 1983 .-- V.48. P.3545-3548] [3].

A known method for the dehydrohalogenation of haloalkanes [Natitan Kornrlijrmo, Robert A. Smileyi, Herbert E. Ungnade, Alan M. Whitr, Bernard Taub, Stephean A. Herbert. The Reaction of Silver Nitrite with Secondary and Tertiary Alkyl Halides // J. Am. Chem. Soc. - 1955. - V.77. - P.5528-5533] [4].

Widely known methods for producing highly branched trimers of propylene from ketones [William D. Hinsberg III, Peter G. Schultz, Peter B. Dervan. Direct studies of 1,1-diazenes. Syntheses, infrared and electronic spectra, and kinetics of the thermal decomposition of N- (2,2,6,6-tetramethylpiperidyl) nitrene and N- (2,2,5,5-tetramethylpyrrolidyl) nitrene // J. Am. Chem. Soc. - 1982. - V.104. - P.766-773 [5]; J. A. Kampmeier, S. H. Harris, D. K. Wedegaertner. Tests for free-radical intermediates in the decarbonylation of aldehydes by tris (triphenylphosphine) chlororhodium (I) // J. Org. Chem. - 1980. - V.45. - P.315-318 [6]; B. Badet, M. Julia, J. M. Mallet, C. Schmitz. On the regioselectivity of elimination reactions in terpene derivatives // Tetrahedron. - 1988 .-- V.44. - P.2913-2924] [7], dehydration of alcohols [J. Edward Starr, Richard H. Eastman. Structural Features Facilitating the Photodecarbonylation of Cyclic Ketones 1, 2 // J. Org. Chem. - 1966. - V.31. - P.1393-1402.] [8], as well as by multistage sequential syntheses [Kenneth J. Kolonko, Robert H. Shapiro. Elimination of tertiary alpha-hydrogens from tosylhydrazones with lithium diisopropylamide: preparation of trisubstituted alkenes // J. Org. Chem. - 1978. - V.43. - P.1404-1408 [9]; Morris E. Lewellyn, D. Stanley Tarbell. Formation of a cyclohexane ring by condensation of a nitro ketone and an aldehyde // J. Org. Chem. - 1974. - V.39. - P.1407-1410.] [10].

The disadvantages of the known methods are the difficult process conditions, multi-stage, low yields and, as a consequence, insignificant profitability. Thus, all methods presented in the literature cannot be considered economically feasible for obtaining not only large-tonnage lots, but also laboratory quantities of branched propylene trimmers under consideration.

A known method for the catalytic preparation of the target product on a heterogeneous zeolite catalyst [Noel D. Lazo, James A. Speed. Reactions of propene on zeolite HY catalyst studied by in situ variable temperature solid-state nuclear magnetic resonance spectroscopy. // J. Am. Chem. Soc. - 1989. - V.111. - P.2052-2058] [11].

The method is of certain interest from the point of view of academic science in terms of studying the mechanisms of the reactions of olefin conversion, but it is not considered by the authors as a potential industrial method.

The above method is the closest known solution to the proposed method according to the technical nature. The method involves the catalytic trimerization of propylene into highly branched products in a heterogeneous catalytic system comprising silicon oxides [Noel D. Lazo, James A. Speed. Reactions of propene on zeolite HY catalyst studied by in situ variable temperature solid-state nuclear magnetic resonance spectroscopy. // J. Am. Chem. Soc. - 1989. - V.111. - P.2052-2058] [11].

The disadvantages of this catalytic system used in the method is its low activity and low yield of the target product.

The technical result of the proposed solution is to increase the yield of highly branched propylene trimers and reduce the complexity of the process for their preparation.

The technical result is achieved by obtaining highly branched trimers of propylene (2,6-dimethylheptene-3, 2,6-dimethylheptene-2, 4,6-dimethylheptene-3, 2-methyl-octene-2, 7-methyl-octene-3) in a heterogeneous catalytic system, including silicon oxides. The catalyst used is a nickel (II) complex - bis-allyl nickel Ni (C ₃ H ₅ ) ₂ , deposited on siliceous valves of diatoms with a specific surface area of 20 to 165 m ² / g.

First, the preliminary formation of the catalyst is carried out by vacuum condensation of the bis-allyl nickel complex Ni (C ₃ H ₅ ) ₂ on siliceous valves obtained from biomass of diatoms or on diatomite, which is a leaf of fossil diatoms. Next, catalytic trimerization of propylene in toluene is carried out with active stirring of a suspension of the catalyst in toluene in a propylene atmosphere, while the nickel content in the catalyst is 0.4-10.5% by weight, the reaction is carried out at a temperature of 20-25 ° C and atmospheric pressure. The reaction is monitored volumetrically. The reaction is terminated when propylene absorption ceases to separate the desired product by fractional distillation.

During the formation of the catalyst, a vacuum condensation reaction of bis-allyl nickel (Ni (C ₃ H ₅ ) ₂ on siliceous flaps of diatoms at the boiling point of liquid nitrogen is carried out. The resulting condensate is heated to a temperature of 1-2 ° C and kept at this temperature for 10 minutes, then vacuum and kept in vacuum at a pressure of 0.01-0.005 mm Hg and a temperature of 1-2 ° C for 30 minutes, then the temperature of the system is raised to 20-25 ° C.

Siliceous diatoms are obtained by removing the organic components from the biomass of diatoms of the species Synedra acus, grown in a freshwater culture medium, or using sedimentary rock diatomite, consisting mainly of siliceous valves of fossil diatoms.

To implement the method, silicon flaps with a developed specific surface (not less than 165 m ² / g) obtained by modifying diatomite by applying a layer of highly porous silica are also used.

Modification of diatomite is carried out in order to increase its specific surface. To carry out the modification, siliceous diatomite flaps are impregnated with an ethanol solution of a mixture containing oligosilicates and an organic polymer, followed by drying of the product and its calcination.

The possibility of implementing the method of catalytic trimerization of propylene is illustrated by the following examples of its implementation in laboratory conditions.

Example 1

15 g of Synedra acus biomass containing 11% dry matter was placed in 28 ml of a 2% aqueous solution of sodium dodecyl sulfate and stirred with a mechanical stirrer in a round bottom flask while heating in a boiling water bath for one hour. After cooling to room temperature, the suspension is centrifuged at 4000 g for 2 minutes. Treatment with sodium dodecyl sulfate solution is repeated. Next, the biomass is washed by suspension in distilled water (5 × 26.7 ml) and centrifuged at 4000 g for 2 minutes. After washing with water, the resulting mass is washed twice with 20 ml of isopropyl alcohol and dried under reduced pressure (about 15 mmHg) and 100 ° C to constant weight. The yield of dry biomass was 1.283 g.

To completely remove the organic component, the resulting dry light green biomass in the amount of 1.283 g is poured into 55 ml of concentrated nitric acid in a liter glass beaker. After keeping at room temperature for one day, the mixture was diluted with distilled water in a quantitative ratio of 1: 2, respectively, then filtered on a Buchner funnel and washed with distilled water (5 × 20 ml). The filtered biomass is kept for one day in a mixture consisting of 6.7 ml of concentrated sulfuric acid and 6.7 ml of 30% hydrogen peroxide at room temperature. After that, the mixture is diluted in 27 ml of distilled water, filtered on a Buchner funnel, washed with 30 ml of 2.5% aqueous ammonia solution and then with distilled water to a neutral medium (300 ml of water up to 5 times). After drying in an oven at 150 ° C for three hours, the mass of the obtained silica (siliceous flaps) was 1.05 g, with a specific surface area determined by nitrogen sorption, S _beats = 20 m ² / g. This product is used to further prepare the catalyst.

The formation of the catalyst is carried out by condensation in vacuum of bis-allyl nickel (Ni (C ₃ H ₅ ) ₂ on siliceous flaps at the boiling point of liquid nitrogen. To do this, take 200 mg of Ni (C ₃ H ₅ ) ₂ per 200 mg of silica. The resulting condensate is heated to a temperature of 1-2 ° C and kept at this temperature for 10 minutes, then vacuum and kept in vacuum at a pressure of 0.01-0.005 mm Hg and a temperature of 1-2 ° C for 30 minutes. system to 20-25 ° C. Then the vessel with the obtained catalyst is filled with pure argon for storage I am a catalyst in an argon atmosphere.

Trimerization of propylene is as follows. 100 mg of the formed catalyst are placed under argon in a thermostatted glass vessel, which allows active mixing by shaking. 10 ml of toluene is added to the vessel, propylene is fed and the shaker is turned on. The trimerization process is 60 minutes. After completion of the reaction, the resulting mixture was treated with 100 ml of cold water and the organic layer was separated. The resulting mixture of organic substances containing toluene and olefins is subjected to fractional distillation at atmospheric pressure. Obtain about 2.2 g of olefins, among which, according to GC MASS and NMR 10.4% - 2,6-dimethylheptene-3; 13.4% - 2,6-dimethylheptene-2; 8.1% - 4,6-dimethylheptene-3, 3,7% - 2-methyl-octene-2, 3,6% - 7-methyl-octene-3. The rest is based on chromatography-mass spectrometry of olefins of composition C6. The data on the nickel content in the catalyst and the total activity of the catalyst for the conversion of propylene are shown in the table.

Example 2

The preparation of siliceous flaps and the formation of a catalyst is carried out similarly to the description described in Example 1. Next, after the Ni (C ₃ H ₅ ) ₂ complex is condensed on silica, the system is kept at a temperature of 1-2 ° C for 5 minutes. The nickel content in the catalyst was 5.8%.

The propylene trimerization process is carried out with vigorous stirring 100 mg of the formed catalyst in toluene medium with propylene being fed to it until the reaction of its absorption ceases. The resulting mixture was separated using cold water, adding it in an amount of 100 ml. Then a layer of organic substances is separated and subjected to fractional distillation.

According to GLC, MASS and NMR, the resulting products contain 17.2% - 2,6-dimethylheptene-3; 8.7% - 2,6-dimethylheptene-2; 16.7% - 4,6-dimethylheptene-3, 1.8% - 2-methyl-octene-2, 2.3% - 7-methyl-octene-3. The rest - according to chromatography-mass spectrometry - is made up of olefins of composition C6.

The nickel content in the catalyst and the total activity of the catalyst in the conversion of propylene are shown in the table.

Example 3

1.15 g of flint valves obtained from Synedra acus biomass as in Example 1 is placed in 120 g of a 3% solution of potassium hydroxide in 95% ethanol. The contents are stirred with a mechanical stirrer at room temperature for 47 minutes. Then the mixture is acidified with 26 ml of 10% hydrochloric acid, filtered on a Buchner funnel, washed with distilled water (5 times in 30 ml). Stirred in a glass with 50 ml of 2.5% aqueous ammonia solution, filtered on a Buchner funnel and washed with distilled water to a neutral pH value (5 times in 30 ml). The resulting precipitate is fractionated by precipitation of the suspension in a 1 L glass. The precipitate is placed in an ultrasonic bath for exposure to it with ultrasound for 20 minutes and dried for 2 hours at 150 ° C. A fraction of the flaps dropped in 30 minutes is taken. The output of silica was 0.4 g, its specific surface area S _beats = 135 m ² / g.

The formation of the catalyst is carried out on the obtained silicon flaps with an increased specific surface area similar to that described in example 1. The formed catalyst contains 0.46% nickel.

Trimerization of propylene is carried out in accordance with the description given in example 1. The amount of reacted propylene was determined volumetrically. The obtained target product contains olefins of the following composition: 12.7% - 2,6-dimethylheptene-3; 7.4% - 2,6-dimethylheptene-2; 12.6% - 4,6-dimethylheptene-3, 5,6% - 2-methyl-octene-2, 3,8% - 7-methyl-octene-3. The rest are olefins of composition C6. Data obtained by GLC MASS and NMR.

The nickel content in the catalyst and the total activity of the catalyst in the conversion of propylene are shown in the table.

Example 4

As siliceous flaps, diatomite modified by precipitation of oligosilicates is used to increase its specific surface.

Use diatomite brand Hyflo Super Cel company "Celite Corporation", S _beats <1 m ² / year A portion of polyethylene glycol in an amount of 1.3 g was dissolved in 20 g of ethanol (water content - 4%), 0.26 ml of 1 M hydrochloric acid and tetraethoxysilane in an amount of 3 g were added. The solution was shaken for 2 hours at room temperature and added with stirring 1 g of diatomite. The solvent is evaporated from the resulting suspension by shaking on a shaker at room temperature in air for 6 hours. The mixture is then blown with warm air (50-60 ° C) for 2 hours, while continuing to shake. The resulting powder was dried for 1 h at 100 ° C and kept in a muffle furnace at 550 ° C for 5 hours, obtaining a modified diatomite in the amount of 1.35 g. The specific surface area of the obtained diatomite S _beats = 165 m ² / g.

The formation of the catalyst and catalytic trimerization of propylene is carried out similarly to the description given in example 1. The nickel content in the catalyst was 2.1%. The total activity of the catalyst for the conversion of propylene is given in the table.

The obtained product according to GLC MASS and NMR contains 8.2% - 2,6-dimethylheptene-3; 10.4% - 2,6-dimethylheptene-2; 6.2% - 4,6-dimethylheptene-3, 8.1% - 2-methyl-octene-2, 7.2% - 7-methyl-octene-3. The rest - according to chromatography-mass spectrometry - olefins composition C6.

Examples 2 and 3 demonstrate the influence of the methods of formation and the specific surface area of the carrier on the nickel content in the catalyst, as well as on the activity of the catalyst. Example 4 traces the effect of the nature of the starting silica matrix.

As a result of the method, it becomes possible to obtain valuable branched trimers of propylene. The advantage of the method is the use of cheap raw materials (propylene) and a highly active heterogeneous catalyst obtained from affordable and inexpensive reagents - silica valves of diatoms and nickel salts.

Table The method of obtaining highly branched propylene trimmers Example No. Nickel content,% Activity, mol C ₃ H _{6 /} g.cat.*h Activity, mol С ₃ Н ₆ / molNi * h one 10.4 21.9 12500 2 5.8 17.9 18300 3 0.46 1.8 23600 four 2.1 5.2 14400

Claims (5)

1. The method of obtaining highly branched trimers of propylene (2,6-dimethylheptene-3, 2,6-dimethylheptene-2, 4,6-dimethylheptene-3, 2-methyl-octene-2, 7-methyl-octene-3) in a heterogeneous catalytic system, including silicon oxides, characterized in that the catalyst used is bis-allyl nickel Ni (C ₃ H ₅ ) ₂ deposited on siliceous flaps of diatoms with a specific surface area of 20 to 165 m ² / g, the catalytic trimerization of propylene is carried out in toluene at actively stirring a suspension of the catalyst in toluene in an atmosphere of prop ilene, while the nickel content in the catalyst is 0.4-10.5% by weight, the reaction is carried out at a temperature of 20-25 ° C and atmospheric pressure. 2. The method for producing highly branched propylene trimers according to claim 1, characterized in that the catalyst is preliminarily formed by vacuum condensation of Ni (C ₃ H ₅ ) ₂ on siliceous flaps obtained from biomass of diatoms, or on diatomite, and then catalytic trimerization is carried out propylene in toluene medium, the progress of the reaction is controlled by volumetric measurements, the reaction is terminated when propylene absorption ceases to separate the target product by fractional distillation. 3. A method of producing highly branched propylene trimers according to any one of claims 1 or 2, characterized in that during the formation of the catalyst, a vacuum condensation reaction of nickel bis-allyl Ni (C ₃ H ₅ ) ₂ is carried out on siliceous valves of diatoms at a boiling point of liquid nitrogen , the resulting condensate is heated to a temperature of 1-2 ° C and maintained at this temperature for 10 minutes, after which it is vacuumized and kept in a vacuum at a pressure of 0.01-0.005 mm Hg. and a temperature of 1-2 ° C for 30 minutes, then the temperature of the system is adjusted to 20-25 ° C. 4. The method for producing highly branched propylene trimers according to claim 1, characterized in that siliceous flaps of diatoms obtained by removing organic components from biomass of diatoms of the species Synedra acus grown in a freshwater culture medium are used. 5. The method for producing highly branched propylene trimmers according to claim 1, characterized in that siliceous flaps of diatoms with a developed specific surface are used, obtained by modifying diatomite by applying a layer of highly porous silica.