Synthetic method of organic boron amine salt cocatalyst

Abstract

The invention is suitable for the technical field of chemical synthesis, and provides a synthesis method of an organic boron amine salt cocatalyst, which comprises the following steps: placing boron salt and organic amine in an organic solvent, controlling the reaction temperature, adding a halogenated silane compound under stirring operation, continuously stirring the obtained mixture, reacting, dropwise adding alcohol into the reaction liquid, and reacting to obtain the organic boron amine salt cocatalyst. Turbid liquid is obtained; controlling the temperature of the obtained turbid liquid to room temperature, continuously stirring, filtering to remove insoluble substances, and performing vacuum decompression to remove the solvent to obtain an organic boron amine salt cocatalyst; wherein the halogenated silane compound is one of trimethylchlorosilane, dimethyl chlorosilane, methyl trichlorosilane and silicon tetrachloride. According to the present invention, the alcohol and the halogenated silane are subjected to the in-situ reaction to generate the hydrogen chloride as the reaction reagent to react with the boron salt and the organic amine so as to directly obtain the water-free organic boron amine salt cocatalyst, such that the disadvantage that the large-scale production cannot be performed in the existing reaction can be effectively avoided, and the industrial large-scale production requirement can be easily achieved.

Description

Technical Field

[0001] This invention belongs to the field of chemical synthesis technology, and particularly relates to a method for synthesizing an organoboramine salt cocatalyst. Background Technology

[0002] Organoboron salts, especially some organoboronamine salts, are important cocatalysts widely used in metallocene olefin polymerization catalyst systems. The use of organoboron salt cocatalysts can significantly reduce the olefin polymerization industry's dependence on methylaluminoxanes and alkylaluminates. Common organoboronamine salts, such as N,N-dimethylaniline-tetra(pentafluorophenyl)borate, have excellent solubility in aromatic hydrocarbon solvents but very low solubility in aliphatic alkanes, which are primarily used as reaction solvents in industrial polymerization. The limited solubility of organoboronamine salts in alkanes restricts their industrial application.

[0003] Conventional organoboronamine salt cocatalysts are prepared using hydrochloric acid aqueous solution as a reagent, followed by drying to remove moisture that affects polymerization. However, due to the high viscosity of some organoboronamine salts, recrystallization purification is not possible, failing to remove residual moisture and resulting in low activity of the cocatalyst during use. Currently, dehydration methods for organoboronamine salts mainly include azeotropic methods and alkylaluminum dehydration methods, but these methods are very complex and not conducive to scale-up production. Existing technologies disclose the direct preparation of anhydrous soluble organoboronamine salt cocatalysts by ball milling boron salts and organic amine hydrochlorides. However, this method is time-consuming and produces a small amount of material, limiting the scale-up production of such cocatalysts. Furthermore, it requires the prior preparation of anhydrous amine hydrochlorides. Existing technologies also disclose the method of passing dry hydrogen halide gas into a mixture of organoboron salts and amines in a dry solvent to obtain organoboronamine salt cocatalysts. However, this process requires both dry solvents and dry hydrogen halide gas, which is not conducive to large-scale production.

[0004] In summary, from the perspective of large-scale industrial applications, there is a need to develop a simpler method to prepare anhydrous organoboramine salt cocatalysts. Summary of the Invention

[0005] The purpose of this invention is to provide a method for synthesizing organoboramine salt cocatalysts, aiming to solve the problems mentioned in the background art.

[0006] The present invention is implemented as follows: a method for synthesizing an organoboramine salt co-catalyst includes the following steps: Boron salt and organic amine were placed in an organic solvent, and the reaction temperature was controlled. A halosilane compound was added while stirring. The mixture was stirred and the reaction was carried out. An alcohol was added dropwise to the reaction solution to obtain a suspension. The obtained suspension was kept at room temperature and stirred. Then, the insoluble matter was removed by filtration and the solvent was removed by vacuum decompression to obtain the organoboramine salt co-catalyst. The halosilane compound is one of trimethylchlorosilane, dimethylchlorosilane, methyltrichlorosilane, and silicon tetrachloride.

[0007] This invention provides a method for synthesizing an organoboramine salt cocatalyst. In a reaction system of boron salt and organic amine, a certain amount of a halosilane compound is first added. The halosilane compound hydrolyzes with water, releasing hydrogen halide gas, which then reacts with the boron salt and organic amine to obtain the organoboramine salt cocatalyst. No water is introduced during the entire reaction process; any water present in the system is decomposed and removed by the halosilane compound. After stirring for a certain period, an alcohol is added to the system to react with excess halosilane compound, releasing hydrogen chloride gas to participate in the reaction between the boron salt and organic amine, ensuring the reaction proceeds to completion. The organoboramine salt cocatalyst obtained in this invention has extremely low water content. This method is simple to operate, has low risk, and is highly suitable for industrial scale-up production. Attached Figure Description

[0008] Figure 1 The 1H NMR spectrum of the product provided in Example 1 of this invention; Figure 2 The NMR fluorine spectrum of the product provided in Example 1 of this invention; Figure 3 The boron NMR spectrum of the product provided in Example 1 of this invention; Figure 4 The 1H NMR spectrum of the product provided in Example 10 of this invention; Figure 5 The NMR fluorine spectrum of the product provided in Example 10 of this invention; Figure 6 The boron NMR spectrum of the product provided in Example 10 of this invention; Figure 7 The 1H NMR spectrum of the product provided in Example 12 of this invention; Figure 8 The NMR fluorine spectrum of the product provided in Example 12 of this invention; Figure 9 The boron NMR spectrum of the product provided in Example 12 of this invention. Detailed Implementation

[0009] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0010] The organic solvent described in the embodiments of the present invention can be a single organic solvent or a mixture of multiple organic solvents, and can be alkanes, haloalkanes, aromatics, haloaromatics, cycloalkanes, etc., wherein cycloalkanes and haloalkanes are preferred, and may contain one or more cycloalkanes and haloalkanes, and may also contain one or more other types of components under different conditions, such as alkanes and aromatics; preferably cyclohexane, methylcyclohexane, and dichloromethane; The alcohol can be methanol, ethanol, propanol, isopropanol, n-butanol, or a mixture of two of the above alcohols; preferably methanol. Unless otherwise specified, the boron salt can be understood as a tetraarylboron salt. The aryl group can be phenyl, naphthyl, or a polyfluoroaryl group with multiple fluorine atoms substituted. A polyfluoroaryl group refers to a fluorinated aryl group having at least two fluorine atoms or at least two perfluoroalkyl groups or at least one fluorine atom or at least one perfluoroalkyl group directly bonded to the aromatic ring. Preferably, at least two fluorine atoms or at least two perfluoroalkyl groups are directly bonded to the aromatic ring. Each position on the aromatic ring of the fluoroaryl group that is not a fluorine atom or a perfluoroalkyl group can be substituted by a hydrogen atom, a hydrocarbon group, or an alkoxy group. The aromatic ring of the fluoroaryl group includes, but is not limited to, benzene, naphthalene, anthracene, biphenyl, and phenanthrene, preferably benzene or naphthalene. The perfluoroalkyl group can be an alkyl or aryl perfluorinated compound, including but not limited to trifluoromethyl, pentafluoroethyl, pentafluorophenyl, and heptafluoronaphthyl. The hydrocarbon substituents of the aryl group are preferably C1 to C1. 24 Alkyl or C6 to C 30 Aryl or aryl groups, including but not limited to examples of methyl, ethyl, isopropyl, tert-butyl, cyclopentyl, methylcyclohexyl, decyl, phenyl, tolyl, xylyl, benzyl, and naphthyl, wherein the alkoxy group preferably has C1 to C2. 24 Examples of the alkyl moiety, including but not limited to alkoxy groups, include methoxy, ethoxy, isopropoxy, cyclohexyloxy, and methylcyclopentoxy; examples of fluoroaryl groups present on the borate moiety in the embodiments of the present invention include 3,5-bis(trifluoromethyl)phenyl, 2,4,6-tris(trifluoromethyl)-phenyl, and 4-[tris(isopropyl) [Silyl]-tetrafluorophenyl, 4-[dimethyl(tert-butyl)silyl]-tetrafluorophenyl, 4′-(methoxy)-octafluoro-1-biphenyl-4-yl, 2,3-bis(pentafluoroethyl)-naphthyl, 2-(isopropoxy)-hexafluoronaphthyl, 9,10-bis(heptafluoropropyl)-heptafluoroanthrayl, 9,10-bis(p-tolyl)-heptafluorophenanthryl; preferably, at most two substituents on the ring of the fluoroaryl group are hydrocarbon groups or perfluorohydrocarbon groups, while the remaining substituents are fluorine atoms; preferably, the fluoroaryl group is the choice in which all substituents are fluorine atoms, examples of such groups are pentafluorophenyl, nonafluoro-1-biphenyl-4-yl, nonafluoro-1-biphenyl-3-yl, 1-heptafluoronaphthyl, 2-heptafluoronaphthyl, 7-nonafluoroanthrayl, 9-nonafluorophenanthryl and similar groups, preferred perfluoroaryl groups include pentafluorophenyl and heptafluoronaphthyl; The organic amine refers to an organic amine containing a long organic chain, with the general molecular formula NR1R2R3, where R1, R2, and R3 can be the same or different, and can be alkyl or aromatic substituents containing C6-C30 chains, such as phenyl, o-methylphenyl, etc. The reaction temperature range in the embodiments of the present invention is -20°C to 50°C; preferably 0°C to 40°C.

[0011] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0012] Example 1: A method for synthesizing an organoboroamine salt cocatalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, add potassium borohydride K[B(C6F5)4] (7.18 g, 10 mmol) and an organic amine (C 18 H 37 )2NMe (5.36 g, 10 mmol) and 100 mL of dichloromethane were added, and the system temperature was stabilized at -20 °C. Trimethylchlorosilane (2.16 g, 20 mmol) was slowly added with stirring. The mixture was stirred for 1 hour, and methanol (0.64 g, 20 mmol) was slowly added dropwise to the reaction solution. The resulting suspension was heated to room temperature and stirred for 1 hour, then filtered. The resulting dichloromethane solution was dried under vacuum to obtain a pale yellow viscous liquid with a yield of 95%, yielding the product [(C 18 H 37 )2NHMe][(C6F5)4B].

[0013] The prepared product was analyzed, and the following NMR spectra were obtained: 1H NMR spectrum, fluorine NMR spectrum, and boron NMR spectrum. Figures 1 to 3 As shown.

[0014] Example 2: A method for synthesizing an organoboroamine salt co-catalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, add potassium borohydride K[B(C6F5)4] (7.18 g, 10 mmol) and an organic amine (C 18 H 37 )2NMe (5.36 g, 10 mmol) and 100 mL of dichloromethane were added, and the system temperature was stabilized at 0 °C. Trimethylchlorosilane (2.16 g, 20 mmol) was slowly added with stirring. The mixture was stirred for another hour, and methanol (0.64 g, 20 mmol) was slowly added dropwise to the reaction solution. The resulting suspension was heated to room temperature and stirred for another hour before being filtered. The resulting dichloromethane solution was dried under vacuum to obtain a pale yellow viscous liquid with a yield of 93%, yielding the product [(C 18 H 37The nuclear magnetic resonance characterization of [2NHMe][(C6F5)4B] was consistent with that of Example 1.

[0015] Example 3: A method for synthesizing an organoboramine salt co-catalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, add potassium borohydride K[B(C6F5)4] (7.18 g, 10 mmol) and an organic amine (C 18 H 37 2NMe (5.36 g, 10 mmol) and 100 mL of dichloromethane were added, and the system temperature was stabilized at 30 °C. Trimethylchlorosilane (2.16 g, 20 mmol) was slowly added with stirring. The mixture was stirred for another hour, and methanol (0.64 g, 20 mmol) was slowly added dropwise. The resulting suspension was heated to room temperature and stirred for 1 hour before filtration. The resulting dichloromethane solution was dried under vacuum to obtain a pale yellow viscous liquid. The yield was 90%, and the product [(C 18 H 37 [2NHMe][(C6F5)4B], whose NMR characterization was consistent with the results of Example 1.

[0016] Example 4: A method for synthesizing an organoboronamine salt co-catalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, add potassium borohydride K[B(C6F5)4] (7.18 g, 10 mmol) and an organic amine (C 18 H 37 )2NMe (5.36 g, 10 mmol) and 100 mL of cyclohexane were added, and the system temperature was stabilized at 50 °C. Trimethylchlorosilane (2.16 g, 20 mmol) was slowly added with stirring. The resulting mixture was stirred for 1 hour, and methanol (0.64 g, 20 mmol) was slowly added dropwise to the reaction system. The resulting suspension was cooled to room temperature and stirred for 1 hour before being filtered. The resulting cyclohexane solution was dried under vacuum to obtain a pale yellow viscous liquid with a yield of 96%, yielding the product [(C 18 H 37 [2NHMe][(C6F5)4B], whose NMR characterization was consistent with the results of Example 1.

[0017] Example 5: A method for synthesizing an organoboroamine salt co-catalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, add potassium borohydride K[B(C6F5)4] (7.18 g, 10 mmol) and an organic amine (C 18 H 37)2NMe (5.36 g, 10 mmol) and 100 mL of methylcyclohexane were added, and the system temperature was stabilized at 20 °C. Trimethylchlorosilane (2.16 g, 20 mmol) was slowly added dropwise with stirring. The resulting mixture was reacted for another hour, and methanol (0.32 g, 10 mmol) was slowly added dropwise to the reaction system. The resulting suspension was stirred for another hour and then filtered. The resulting methylcyclohexane solution was dried under vacuum to obtain a pale yellow viscous liquid with a yield of 85%, yielding the product [(C 18 H 37 [2NHMe][(C6F5)4B], whose NMR characterization is consistent with that of Example 1.

[0018] Example 6: A method for synthesizing an organoboroamine salt co-catalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, add potassium borohydride K[B(C6F5)4] (7.18 g, 10 mmol) and an organic amine (C 18 H 37 )2NMe (5.36 g, 10 mmol) and 100 mL of dichloromethane were added, and the system temperature was stabilized at 20 °C. Trimethylchlorosilane (3.24 g, 30 mmol) was slowly added dropwise with stirring. The resulting mixture was reacted for another hour, and methanol (0.64 g, 20 mmol) was slowly added dropwise to the system. The resulting suspension was stirred for another hour and then filtered. The resulting dichloromethane solution was dried under vacuum to obtain a pale yellow viscous liquid with a yield of 92%, yielding the product [(C 18 H 37 [2NHMe][(C6F5)4B], whose NMR characterization is consistent with that of Example 1.

[0019] Example 7: A method for synthesizing an organoboroamine salt co-catalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, add potassium borohydride K[B(C6F5)4] (7.18 g, 10 mmol) and an organic amine (C 18 H 37 )2NMe (5.36 g, 10 mmol) and 100 mL of dichloromethane were added, and the system temperature was stabilized at 20 °C. Trimethylchlorosilane (2.16 g, 20 mmol) was slowly added dropwise with stirring. The resulting reaction solution was stirred for 2 hours, and ethanol (0.92 g, 20 mmol) was slowly added dropwise to the reaction system. The resulting suspension was stirred for 1 hour and then filtered. The resulting dichloromethane solution was dried under vacuum to obtain a light yellow viscous liquid with a yield of 93%, yielding the product [(C 18 H 37 [2NHMe][(C6F5)4B], whose NMR characterization is consistent with that of Example 1.

[0020] Example 8: A method for synthesizing an organoboramine salt co-catalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, add potassium borohydride K[B(C6F5)4] (7.18 g, 10 mmol) and an organic amine (C 18 H 37 )2NMe (5.36 g, 10 mmol) and 100 mL of dichloromethane were added, and the system temperature was stabilized at 20 °C. Trimethylchlorosilane (2.16 g, 20 mmol) was slowly added dropwise with stirring. The resulting reaction solution was stirred for 0.5 hours, and isopropanol (1.20 g, 20 mmol) was added dropwise to the reaction system. The resulting suspension was stirred for 2 hours and then filtered. The resulting dichloromethane solution was dried under vacuum to obtain a light yellow viscous liquid with a yield of 97%, yielding the product [(C 18 H 37 [2NHMe][(C6F5)4B], whose NMR characterization is consistent with that of Example 1.

[0021] Example 9: A method for synthesizing an organoboronamine salt co-catalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, add sodium borohydride Na[B(C6F5)4] (7.02 g, 10 mmol) and an organic amine (C 18 H 37 )2NMe (5.36 g, 10 mmol) and 100 mL of dichloromethane were added, and the system temperature was stabilized at 20 °C. Trimethylchlorosilane (2.16 g, 20 mmol) was slowly added dropwise with stirring. The resulting reaction solution was stirred for 2 hours, and methanol (0.64 g, 20 mmol) was slowly added dropwise to the reaction system. The resulting suspension was stirred for 1 hour and then filtered. The resulting dichloromethane solution was dried under vacuum to obtain a light yellow viscous liquid with a yield of 93%, yielding the product [(C 18 H 37 [2NHMe][(C6F5)4B], whose NMR characterization is consistent with that of Example 1.

[0022] Example 10: A method for synthesizing an organoboramine salt co-catalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, add potassium borohydride K[B(C6F5)4] (7.18 g, 10 mmol) and an organic amine (C 18 H 37)2NPh (5.98 g, 10 mmol) and 100 mL of dichloromethane were added, and the system temperature was stabilized at 20 °C. Trimethylchlorosilane (1.08 g, 10 mmol) was slowly added dropwise with stirring. The resulting reaction solution was stirred for 1 hour, and methanol (0.64 g, 20 mmol) was slowly added dropwise to the reaction system. The resulting suspension was stirred for 3 hours and then filtered. The resulting dichloromethane solution was dried under vacuum to obtain a light yellow viscous liquid with a yield of 95%, yielding the product [(C 18 H 37 )2NHPh][(C6F5)4B].

[0023] The prepared product was analyzed, and the following NMR spectra were obtained: 1H NMR spectrum, fluorine NMR spectrum, and boron NMR spectrum. Figures 4 to 6 As shown.

[0024] Example 11: A method for synthesizing an organoboramine salt co-catalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, add sodium borohydride Na[B((3,5-(CF3)2C6H3)4] (8.86 g, 10 mmol) and an organic amine (C 18 H 37 )2NMe (5.36 g, 10 mmol) and 100 mL of dichloromethane were added, and the system temperature was stabilized at 20 °C. Dimethylchlorosilane (1.29 g, 10 mmol) was slowly added dropwise with stirring. The resulting mixture was reacted for another hour, and methanol (0.64 g, 20 mmol) was slowly added dropwise to the reaction system. The resulting suspension was stirred for 2 hours and then filtered. The resulting dichloromethane solution was dried under vacuum to obtain a light yellow viscous liquid with a yield of 96%, yielding the product [(C 18 H 37 [2NHMe][(C6F5)4B], whose NMR characterization was consistent with the results of Example 1.

[0025] Example 12: A method for synthesizing an organoboramine salt co-catalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, potassium borohydride K[B(C6F5)4] (7.18 g, 10 mmol), organic amine Me2NPh (1.21 g, 10 mmol), and 100 mL of dichloromethane were added. The system temperature was stabilized at 20 °C, and methyltrichlorosilane (3.01 g, 20 mmol) was slowly added dropwise with stirring. The resulting mixture was allowed to react for 1 hour, and methanol (0.64 g, 20 mmol) was slowly added dropwise to the reaction system. The resulting suspension was stirred for 1 hour and then filtered. The resulting dichloromethane solution was dried under vacuum to obtain a white crystalline solid with a yield of 94%, yielding the product [Me2PhNH][(C6F5)4B].

[0026] The prepared product was analyzed, and the following NMR spectra were obtained: 1H NMR spectrum, fluorine NMR spectrum, and boron NMR spectrum. Figures 7 to 9 As shown.

[0027] Example 13: A method for synthesizing an organoboramine salt co-catalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, add potassium borohydride K[B(C6F5)4] (7.18 g, 10 mmol) and an organic amine (C 18 H 37 )2NMe (5.36 g, 10 mmol) and 100 mL of dichloromethane were added, and the system temperature was stabilized at 20 °C. Silicon tetrachloride (1.70 g, 10 mmol) was slowly added dropwise with stirring. The resulting reaction solution was stirred for 1 hour, and methanol (0.64 g, 20 mmol) was slowly added dropwise. The resulting suspension was stirred for 2 hours and then filtered. The resulting dichloromethane solution was dried under vacuum to obtain a pale yellow viscous liquid with a yield of 95%, yielding the product [(C 18 H 37 [2NHMe][(C6F5)4B], whose NMR characterization was consistent with the results of Example 1.

[0028] Example 14: A method for synthesizing an organoboramine salt co-catalyst, comprising the following steps: In a three-necked flask equipped with a mechanical stirrer, add lithium boron salt Li[B(C6F5)4] (6.86 g, 10 mmol) and organic amine (C 18 H 37 )2NMe (5.36 g, 10 mmol) and 100 mL of dichloromethane were added, and the system temperature was stabilized at 20 °C. Trimethylchlorosilane (1.08 g, 10 mmol) was slowly added dropwise with stirring. The resulting reaction solution was stirred for 1 hour, and methanol (0.64 g, 20 mmol) was slowly added dropwise to the reaction system. The resulting suspension was stirred for 1 hour and then filtered. The resulting dichloromethane solution was dried under vacuum to obtain a light yellow viscous liquid with a yield of 95%, yielding the product [(C 18 H 37 [2NHMe][(C6F5)4B], whose NMR characterization was consistent with the results of Example 1.

[0029] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for synthesizing an organoboroamine salt co-catalyst, characterized in that, Includes the following steps: Boron salt and organic amine were placed in an organic solvent, and the reaction temperature was controlled. A halosilane compound was added while stirring. The mixture was stirred and the reaction was carried out. An alcohol was added dropwise to the reaction solution to obtain a suspension. The obtained suspension was kept at room temperature and stirred. Then, the insoluble matter was removed by filtration and the solvent was removed by vacuum decompression to obtain the organoboramine salt co-catalyst. The halosilane compound is one of trimethylchlorosilane, dimethylchlorosilane, methyltrichlorosilane, and silicon tetrachloride.

2. The method for synthesizing the organoboronamine salt cocatalyst according to claim 1, characterized in that, The molar ratio of the boron salt, organic amine, halosilane compound and alcohol is 1:1-1.2:1-3:1-2.

3. The method for synthesizing the organoboronamine salt co-catalyst according to claim 1, characterized in that, The boron salt is a phenylboron salt or a perfluoroarylboron salt.

4. The method for synthesizing the organoboronamine salt cocatalyst according to claim 1, characterized in that, The general chemical formula of the organic amine is NR1R2R3, where R1, R2, and R3 are one of alkyl or aromatic substituents containing C6-C30 chains.

5. The method for synthesizing the organoboronamine salt co-catalyst according to claim 1, characterized in that, The organic solvent is one or more of cycloalkanes and haloalkanes.

6. The method for synthesizing the organoboronamine salt cocatalyst according to claim 1, characterized in that, The alcohol is one or more of methanol, ethanol, propanol, isopropanol, and n-butanol.

7. The method for synthesizing the organoboronamine salt cocatalyst according to claim 1, characterized in that, In the step of controlling the reaction temperature, the temperature is -20℃ to 50℃.

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