Composite catalyst, its preparation method and application

Abstract

The application discloses a composite catalyst and a preparation method and application thereof. The composite catalyst comprises iridium and a nitrogen-containing porous organic polymer. The iridium is loaded in the nitrogen-containing porous organic polymer. The nitrogen-containing porous organic polymer is a random copolymer, and a general structure formula is shown as formula I: wherein m and n represent molar amounts of monomers, a molar ratio of m and n is 1:(0-100); R 1 and R 2 are each independently selected from hydrogen, halogen, cyano, amino, C 2～6 alkenyl, C 2～6 alkynyl, C 1～14 alkyl, C 1～6 alkoxy, C 6～14 aryl, C 3～10 heteroaryl containing 1-3 heteroatoms selected from N, O and S. The composite catalyst provided by the application has a large specific surface area, contains a multi-stage pore structure, can efficiently catalyze a silicon-hydrogen addition, has good cyclic catalytic performance, and exhibits excellent activity and regioselectivity, and a reaction yield is high.

Description

Technical Field

[0001] This invention relates to the field of catalyst technology, and in particular to a composite catalyst, its preparation method, and its application. Background Technology

[0002] In organosilicon chemistry, hydrosilylation reactions are crucial for constructing carbon-silicon and oxygen-silicon bonds. The construction of carbon-silicon bonds utilizes abundant silicon, opening up numerous possibilities for the synthesis and application of silicon products. This type of reaction offers significant advantages, such as simple reaction conditions, high operability, few side reactions, and high yields. Hydrosilylation reactions typically require a catalyst, usually a platinum catalyst. However, due to the wide range of applications for organosilicon materials, the demand is increasing, consuming large quantities of platinum metal annually. Typically, this type of platinum catalyst is non-recyclable and lacks selectivity.

[0003] Therefore, it is necessary to develop a new composite catalyst. Summary of the Invention

[0004] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, the first aspect of the present invention proposes a composite catalyst that has cyclic catalytic capability, can efficiently realize hydrosilylation reactions, and exhibits excellent activity and site selectivity in hydrogenation reactions, with high reaction yield.

[0005] A second aspect of the present invention also provides a method for preparing a composite catalyst.

[0006] A third aspect of the present invention also provides an application of the composite catalyst.

[0007] A composite catalyst according to a first aspect of the present invention comprises iridium and a nitrogen-containing porous organic polymer; wherein the iridium is supported in the nitrogen-containing porous organic polymer.

[0008] The nitrogen-containing porous organic polymer is a random copolymer, and its general structural formula is shown in Formula I:

[0009]

[0010] Where m and n represent the molar amounts of the monomers, and the molar ratio of m to n is 1:(0~100);

[0011] R 1 and R 2 Each is independently selected from hydrogen, halogen, cyano, amino, C 2～6 alkenyl, C 2～6 alkynyl group, C 1～14 alkyl, C 1～6 alkoxy, C 6～14aryl group, C containing 1 to 3 heteroatoms selected from N, O and S. 3～10 heteroaryl groups;

[0012] R is selected from one of the following structural formulas:

[0013] The asterisk (*) indicates the location of the aggregated link.

[0014] The composite catalyst according to embodiments of the present invention has at least the following beneficial effects:

[0015] The composite catalyst provided by this invention has a large specific surface area and a hierarchical porous structure, enabling it to efficiently catalyze the direct addition of silylis and hydrosilylation. Furthermore, the composite catalyst of this invention can be recycled and reused, exhibiting excellent cyclic catalytic performance and significantly reducing production costs. In addition, the composite catalyst of this invention demonstrates excellent activity and site selectivity in the silylis and hydrosilylation reaction, resulting in high reaction yields, thus laying the foundation for the industrialization of silylis and hydrosilylation.

[0016] In addition, the nitrogen-containing porous organic polymer of the present invention is used as a support and also as a ligand for the transition metal iridium. The nitrogen in the polymer coordinates with the transition metal iridium, anchoring the transition metal iridium to the solid support. This not only makes it more secure and reduces the loss of iridium, but the nitrogen ligand can also donate electrons to the transition metal iridium, thereby enhancing the catalytic activity of the transition metal iridium.

[0017] On the other hand, compared with traditional supports, the nitrogen-containing organic porous polymer provided by this invention has the following advantages as a catalyst support: (1) higher specific surface area, which is conducive to the high dispersion and exposure of metal active centers; (2) rich multi-level porous structure, which is conducive to the contact between reactants and catalytic active sites and the diffusion and transfer of products, thereby improving catalytic activity; (3) it can act as a "solid" ligand, playing a role similar to "host-guest chemistry". The nitrogen-containing ligand units "built in" in the polymer ("host") provide "anchoring" sites for the metal active centers ("guests") and coordinate to form a catalyst of "quasi-homogeneous metal complex", which is conducive to stabilizing the metal centers and preventing aggregation and loss; (4) the structure of the "built in" nitrogen ligands in the polymer has strong modulatory properties and can be designed and synthesized according to the reaction characteristics and needs. Therefore, the choice of support is crucial to the activity and selectivity of the nitrogen-containing porous organic polymer-supported iridium catalyst of this invention.

[0018] According to some embodiments of the present invention, the iridium content accounts for 0.1% to 10% of the total mass of the composite catalyst. If the loading is too low, it will lead to the waste of a large number of active sites in the solid ligand, and more catalyst will be used in the catalytic process, which is inconvenient to operate; if the loading is too high, there will be relatively fewer active sites, iridium will be easily lost, and the catalyst stability will be poor. Experiments have shown that an iridium loading mass fraction between 0.1% and 10% is more ideal.

[0019] According to some embodiments of the present invention, the iridium content accounts for 1% to 10% of the total mass of the composite catalyst.

[0020] According to some embodiments of the present invention, m represents the molar amount of nitrogen-containing polymeric monomers and n represents the molar amount of comonomer R. The subscripts m and n do not indicate the linking order of the monomers. The linking order of the monomers may not be fixed and is a random polymer.

[0021] According to some embodiments of the present invention, the molar ratio of m to n is 1:(5-20).

[0022] According to some embodiments of the present invention, R 1 and R 2 Independently selected from hydrogen, C 1～10 alkyl, C 1～14 alkoxy, C 6～10 aryl group, C containing one or two heteroatoms selected from N and O 5～10 Mixed aromatic compounds.

[0023] According to some embodiments of the present invention, R1 and R2 are independently selected from at least one of hydrogen, fluorine, chlorine, bromine, vinyl, ethynyl, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, tert-butoxy, cyclopentyl, cyclohexyl, 1-adamantyl, phenyl, 1-naphthyl, 2-furanyl, 2-pyrroleyl, pyranyl or pyridyl.

[0024] The method for preparing the composite catalyst described above according to a second aspect embodiment of the present invention includes the following steps:

[0025] The iridium precursor was prepared by mixing with a nitrogen-containing porous organic polymer and then using an impregnation method.

[0026] According to some embodiments of the present invention, the iridium precursor is selected from at least one of acetylacetone dicarbonyl iridium (I), acetylacetone bis(ethylene) iridium (I), tri(triphenylphosphine) iridium, chlorobisethylene iridium, carbonyl di(triphenylphosphine) iridium chloride (I), bis(4,6-difluorophenylpyridine-N,C2)pyridinecarboxylic acid iridium (III), tri(norbornene)(acetylacetone) iridium (III), 1,5-cyclooctadiene iridium chloride dimer, acetylacetone iridium (I) dimer, (acetylacetone)(1,5-cyclooctadiene) iridium (I), dichloro(pentamethylcyclopentadienyl) iridium (III) dimer, tricarbonyl iridium chloride, and carbonyl dihydrotri(triphenylphosphine) iridium (I).

[0027] According to some embodiments of the present invention, the steps of the impregnation method are as follows:

[0028] Under inert gas protection, the iridium precursor, nitrogen-containing porous organic polymer, and solvent are mixed, heated, and stirred until the solvent is removed to obtain the final product.

[0029] According to some embodiments of the present invention, the solvent is selected from at least one of n-hexane, dichloromethane, ethyl acetate, dimethylformamide, tetrahydrofuran, benzene, ethanol, methanol, or toluene.

[0030] According to some embodiments of the present invention, the heating temperature is 20 to 100°C.

[0031] According to some embodiments of the present invention, the heating temperature is 30–80°C.

[0032] According to some embodiments of the present invention, the stirring time is 2 to 48 hours.

[0033] According to some embodiments of the present invention, the stirring time is 12 to 36 hours.

[0034] According to some embodiments of the present invention, the inert gas includes argon and / or nitrogen.

[0035] According to some embodiments of the present invention, the nitrogen-containing porous organic polymer is prepared by the following method:

[0036] The compound of formula II, comonomer R, organic solvent and initiator are subjected to a polymerization reaction;

[0037] The structural formula of compound II is as follows:

[0038]

[0039] Wherein substituents R, R 1 R 2 The definition of R is the same as that of R mentioned above. 1 R 2The definitions are the same.

[0040] According to some embodiments of the present invention, the polymerization reaction takes 24 to 48 hours.

[0041] According to some embodiments of the present invention, the molar ratio of the compound of formula II to the comonomer R is 1:(0 to 100).

[0042] According to some embodiments of the present invention, the molar ratio of the compound of formula II to the comonomer R is 1:(5-20).

[0043] According to some embodiments of the present invention, the amount of the initiator is 0.1% to 5% of the molar amount of the compound of formula II.

[0044] According to some embodiments of the present invention, the polymerization reaction is carried out at a temperature of 60–150°C.

[0045] According to some embodiments of the present invention, the polymerization reaction is carried out at a temperature of 80–100°C.

[0046] According to some embodiments of the present invention, the compound of formula II is prepared by the following method, with the reaction equation as follows:

[0047]

[0048] Step 1: Add compound 1, potassium vinyltrifluoroborate, bis(triphenylphosphine)palladium dichloride and cesium carbonate to the reactor, dissolve in tetrahydrofuran, carry out the reaction, remove the solvent under reduced pressure, and separate by column chromatography to obtain compound 2;

[0049] Step 2: Compound 2, Compound 3, sodium tert-butoxide and ethanol were mixed and reacted, cooled, quenched with water, extracted with ethyl acetate, and purified by column chromatography to obtain compound II.

[0050] A third aspect of the present invention provides the application of the composite catalyst described above in the catalytic hydrosilylation reaction.

[0051] Definitions and general terms

[0052] “C 1～14 "alkyl" refers to an alkyl group with a total number of carbon atoms of 1-14, including C14 and C24. 1-14 straight-chain alkyl, C 1-14 Branched alkyl groups and C 3-14The cycloalkyl group can be, for example, a straight-chain alkyl group with a total number of carbon atoms of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, or 14; a branched-chain alkyl group with a total number of carbon atoms of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, or 14; or a cycloalkyl group with a total number of carbon atoms of 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, or 14, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, cyclopropyl, methylcyclopropyl, ethylcyclopropyl, cyclopentyl, methylcyclopentyl, cyclohexyl, etc. Regarding "C 1-10 "alkyl" has a similar interpretation, except that the number of carbon atoms is different.

[0053] “C 1-6 "alkoxy group" refers to an alkoxy group with a total number of 1-6 carbon atoms, including C64 and C64. 1-6 straight-chain alkoxy, C 1-6 Branched alkoxy groups and C 2-6 The cycloalkoxy group can be, for example, a straight-chain alkoxy group with a total of 1, 2, 3, 4, 5, or 6 carbon atoms; a branched-chain alkoxy group with a total of 1, 2, 3, 4, 5, or 6 carbon atoms; or a cycloalkoxy group with a total of 2, 3, 4, 5, or 6 carbon atoms, such as methoxy, ethoxy, n-propoxy, isopropoxy, etc. Regarding "C 1-4 The "alkoxy group" has a similar explanation, except that the number of carbon atoms is different.

[0054] “C 2～6 "Alkenyl" refers to a straight-chain or branched hydrocarbon group having one or more double bonds, and the total number of carbon atoms in the alkenyl group is 2-6, and the double bonds in the group can be in any position.

[0055] “C 2～6 "Alkyne" refers to a straight-chain or branched hydrocarbon group with one or more triple bonds, and the total number of carbon atoms in the alkynyl group is 2-6. The triple bonds in the group can be in any position.

[0056] "Halogen" includes any one or more of fluorine, chlorine, bromine, and iodine.

[0057] “C 6～14 "Aryl" indicates an all-carbon monocyclic or fused polycyclic group with a fully conjugated π-electron system and a total number of carbon atoms ranging from 6 to 14. 6～10 "Aryl" has a similar definition.

[0058] "C containing 1 to 3 heteroatoms selected from N, O, and S" 3～10 "Heteroaryl" means that the total number of carbon atoms in the heteroaryl group is 3 to 10, and the number of heteroatoms is 1 to 3, and the heteroatoms are selected from at least one of N, O and S.

[0059] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0060] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0061] Figure 1 The 1H NMR spectrum of compound II-1 from Example 1 of this invention;

[0062] Figure 2 This is the carbon NMR spectrum of compound II-1 from Example 1 of this invention;

[0063] Figure 3 BET spectra of nitrogen-containing porous organic polymer L3 and the composite catalyst Ir@L3-3 prepared in the examples;

[0064] Figure 4 XPS spectra of nitrogen-containing porous organic polymer L3 and composite catalyst Ir@L3-3 prepared in the examples;

[0065] Figure 5 HR-TEM images of nitrogen-containing porous organic polymer L3 and the composite catalyst Ir@L3-3 prepared in the examples;

[0066] Figure 6 HADDF images of nitrogen-containing porous organic polymer L3 and the composite catalyst Ir@L3-3 prepared in the examples;

[0067] Figure 7 EDS elemental images of nitrogen-containing porous organic polymer L3 and the composite catalyst Ir@L3-3 prepared in the examples;

[0068] Figure 8 The catalytic cycle count of the composite catalyst Ir@L3-3 prepared for the example is shown in the figure. Detailed Implementation

[0069] The following are specific embodiments of the present invention, and the technical solutions of the present invention will be further described in conjunction with the embodiments, but the present invention is not limited to these embodiments.

[0070] Unless otherwise specified, the reagents, methods and equipment used in this invention are all conventional reagents, methods and equipment in this technical field.

[0071] Specific surface area and pore structure were measured using a Mack ASAP 2460 physical adsorption analyzer (USA); surface morphology was observed using a Hitachi S-4800 cold field emission scanning electron microscope (Japan). Proton and carbon NMR spectra were measured using a BRUCKER 500MHz NMR analyzer (Germany).

[0072] Preparation of compound II-1:

[0073] Step 1: Preparation of compound 2a

[0074]

[0075] 1 mmol of compound 1a, 1.5 mmol of potassium vinyltrifluoroborate, 0.015 mmol of palladium bis(triphenylphosphine)dichloride, and 0.3 mmol of cesium carbonate were added to a Schlenk tube, dissolved in 3 mL of tetrahydrofuran, and reacted at 70 °C for 8 hours with stirring. The solvent was removed under reduced pressure, and compound 2a was obtained by column chromatography. The NMR data are as follows: 1 H NMR (500MHz, CDCl3) δ8.55(d,J=1.4Hz,1H),7.97(d,J=7.5Hz,1H),7.84(dd,J=7.6,1.5Hz,1H), 6.70(t,J=13.4Hz,1H),5.69(dd,J=13.4,2.6Hz,1H),5.43(dd,J=13.5,2.6Hz,1H),2.60(s,3H).

[0076] Step 2: Preparation of compound II-1

[0077]

[0078] 1 mmol of compound 2a, 1 mmol of 2-amino-3-pyridinecarboxaldehyde compound 3a, and 0.4 mmol of sodium tert-butoxide were added to a Schlenk tube, dissolved in ethanol, and reacted at 60 °C for 3 hours. The mixture was then cooled, quenched with water, extracted with ethyl acetate, and purified by column chromatography to obtain compound II-1. The proton and carbon spectra of the obtained product are shown below. Figure 1 and Figure 2 As shown, the structural characterization data are as follows:

[0079] 1 H NMR(400MHz,Chloroform-d)δ9.06(s,1H),8.77(s,1H),8.63(s,2H),8.20(s,1H ),8.10(s,1H),7.87(s,1H),7.39(s,1H),6.69(s,1H),5.88(s,1H),5.38(s,1H).

[0080] 13 C NMR(101MHz,Chloroform-d)δ158.93,155.76,154.46,153.72,147.61,137.7 1,136.89,133.90,133.54,133.16,122.81,122.30,122.05,119.98,117.00.

[0081] Example 1

[0082] This example provides a composite catalyst, the preparation steps of which are as follows:

[0083] Preparation of nitrogen-containing porous organic polymer L1 (m:n = 1:5); the reaction equation is as follows, and the specific steps are as follows:

[0084]

[0085] Under argon protection, 1 mmol of the prepared compound II-1, 5 mmol of divinylbenzene, and 0.1 mmol of azobisisobutyronitrile (AIBN) were added to a reaction flask, dissolved in 30 mL of THF, and stirred at room temperature for half an hour. The mixture was then transferred to a hydrothermal reactor and reacted at 100 °C for 24 h. After cooling to room temperature, methanol was added for dispersion, followed by centrifugation, washing three times with methanol, and vacuum drying to obtain 0.88 g of nitrogen-containing porous organic polymer L1. The BET specific surface area of ​​this polymer is 350 m² / g. 2 / g, mainly exists in the form of micropores and mesopores.

[0086] Preparation of composite catalysts:

[0087] Under argon protection, 400 mg of nitrogen-containing porous organic polymer L1 was dispersed in 30 mL of methanol, and 67.2 mg of 1,5-cyclooctadiene iridium chloride dimer was added. The mixture was stirred at room temperature for 24 h, centrifuged, washed three times with methanol, and dried under vacuum to obtain 450 mg of the composite catalyst (named Ir@L1, with an iridium content of 5.1 wt%). The BET specific surface area of ​​this composite catalyst is 330 m² / g. 2 / g, mainly exists in the form of micropores and mesopores.

[0088] Example 2

[0089] This example provides a composite catalyst, which includes the following steps:

[0090] Preparation of nitrogen-containing porous organic polymer L2 (m:n = 1:10)

[0091] Under argon protection, 1 mmol of the prepared compound II-1, 10 mmol of divinylbenzene, and 0.2 mmol of azobisisobutyronitrile (AIBN) were added to a reaction flask, dissolved in 50 mL of THF, and stirred at room temperature for half an hour. The mixture was then transferred to a hydrothermal reactor and reacted at 100 °C for 24 h. After cooling to room temperature, methanol was added for dispersion, followed by centrifugation, washing three times with methanol, and vacuum drying to obtain 1.5 g of nitrogen-containing porous organic polymer L2. The BET specific surface area of ​​this polymer is 480 m². 2 / g, mainly exists in the form of micropores and mesopores.

[0092] Preparation of composite catalysts:

[0093] Under argon protection, 400 mg of nitrogen-containing porous organic polymer L2 was dispersed in 30 mL of methanol, and 67.2 mg of 1,5-cyclooctadiene iridium chloride dimer was added. The mixture was stirred at room temperature for 24 h, centrifuged, washed three times with methanol, and dried under vacuum to obtain 450 mg of the composite catalyst (named Ir@L2, with an iridium content of 5.1 wt%). The BET specific surface area of ​​this composite catalyst is 470 m². 2 / g, mainly exists in the form of micropores and mesopores.

[0094] Example 3

[0095] This example provides a composite catalyst, which includes the following steps:

[0096] Preparation of nitrogen-containing porous organic polymer L3 (m:n = 1:20)

[0097] Under argon protection, 1 mmol of the prepared compound II-1, 20 mmol of divinylbenzene, and 0.4 mmol of azobisisobutyronitrile (AIBN) were added to a reaction flask, dissolved in 80 mL of THF, stirred at room temperature for half an hour, transferred to a hydrothermal reactor, and reacted at 100 °C for 24 h. After cooling to room temperature, methanol was added for dispersion, centrifuged, washed three times with methanol, and dried under vacuum to obtain 2.6 g of nitrogen-containing porous organic polymer L3.

[0098] Preparation of composite catalysts:

[0099] Under argon protection, 400 mg of nitrogen-containing porous organic polymer L3 was dispersed in 30 mL of methanol, and 67.2 mg of 1,5-cyclooctadiene iridium chloride dimer was added. The mixture was stirred at room temperature for 24 h, centrifuged, washed three times with methanol, and dried under vacuum to obtain 450 mg of the composite catalyst (named Ir@L3-1, with an iridium content of 4.9 wt%). The BET specific surface area of ​​this composite catalyst is 720 m². 2 / g, mainly exists in the form of micropores and mesopores.

[0100] Example 4

[0101] This example provides a composite catalyst, and the steps are as follows:

[0102] Under argon protection, 400 mg of the nitrogen-containing porous organic polymer L3 prepared above was dispersed in 30 mL of methanol, and 33.6 mg of dichloro(pentamethylcyclopentadienyl)iridium dimer was added. The mixture was stirred at room temperature for 24 h, centrifuged, washed three times with methanol, and dried under vacuum to obtain 420 mg of the composite catalyst (named Ir@L3-2, with an iridium content of 4.1 wt%). The BET specific surface area of ​​this composite catalyst is 750 m² / g. 2 / g, mainly exists in the form of micropores and mesopores.

[0103] Example 5

[0104] This example provides a composite catalyst, and the steps are as follows:

[0105] Under argon protection, 400 mg of the nitrogen-containing porous organic polymer L3 prepared above was dispersed in 30 mL of methanol, 35 mg of tris(triphenylphosphine)iridium was added, stirred at room temperature for 24 h, centrifuged, washed three times with methanol, and dried under vacuum to obtain 410 mg of composite catalyst (named: Ir@L3-3, in which the iridium content is 3.8 wt%).

[0106] BET tests were performed on the nitrogen-containing porous organic polymer L3 and the prepared composite catalyst Ir@L3-3, and the results are as follows: Figure 3 As shown, the BET specific surface area of ​​polymer L3 is 760 m². 2 The catalyst exists primarily in microporous and mesoporous forms, with a BET specific surface area of ​​760 m² / g. 2 / g, mainly exists in the form of micropores and mesopores.

[0107] Figure 4 The XRD pattern of the composite catalyst Ir@L3-3 shows that no obvious peaks were observed belonging to the iridium species, indicating that the iridium in the composite catalyst is highly dispersed or amorphous.

[0108] Figure 5 and Figure 6 The images show the HR-TEM and HAADF-STEM images of the composite catalyst Ir@L3-3, respectively. Electron microscopy reveals that the catalyst does not exhibit aggregation of large iridium particles, indicating that iridium is highly dispersed in the composite catalyst.

[0109] Figure 7 Energy dispersive spectroscopy analysis of each element shows the presence of elements such as iridium, nitrogen, and carbon, which are complexed with each other.

[0110] Application Test Case 1

[0111] The composite catalyst prepared above was subjected to a hydrosilylation reaction, as follows:

[0112] 15 mg of the composite catalyst (Ir@L3-1) was added to a Schlenk tube. Under argon protection, 0.5 mmol of styrene, 0.7 mmol of dimethylphenylsilane, and 2 mL of toluene were added. The mixture was stirred at 100 °C for 12 hours, then cooled to room temperature and purified by column chromatography. Dimethyl(phenyl)(styrene)silane with a molecular weight of 238 was obtained, and the yield was 78% according to gas chromatography analysis.

[0113] Application Test Example 2

[0114] 15 mg of the composite catalyst (Ir@L3-2) was added to a Schlenk tube. Under argon protection, 0.5 mmol of styrene, 0.7 mmol of dimethylphenylsilane, and 2 mL of toluene were added. The mixture was stirred at 100 °C for 12 hours, then cooled to room temperature and purified by column chromatography. Dimethyl(phenyl)(styrene)silane with a molecular weight of 238 was obtained, and the yield was 81% according to gas chromatography analysis.

[0115] Application Test Example 3

[0116] 15 mg of the composite catalyst (Ir@L3-3) was added to a Schlenk tube. Under argon protection, 0.5 mmol of styrene, 0.7 mmol of dimethylphenylsilane, and 2 mL of toluene were added. The mixture was stirred at 100 °C for 12 hours, then cooled to room temperature and purified by column chromatography. Dimethyl(phenyl)(styrene)silane with a molecular weight of 238 was obtained, and the yield was 84% ​​according to gas chromatography analysis.

[0117] Application Test Example 4

[0118] 15 mg of the composite catalyst (Ir@L1) was added to a Schlenk tube. Under argon protection, 0.5 mmol of styrene, 0.7 mmol of dimethylphenylsilane, and 2 mL of toluene were added. The mixture was stirred at 100 °C for 12 hours, then cooled to room temperature and purified by column chromatography. Dimethyl(phenyl)(styrene)silane with a molecular weight of 238 was obtained, and the yield was 67% according to gas chromatography analysis.

[0119] Cyclic test performance

[0120] The composite catalyst (Ir@L3-3) prepared in Example 5 was subjected to a cyclic catalytic experiment. The specific experimental steps are as follows:

[0121] 15 mg of the composite catalyst (Ir@L3-3) was added to a Schlenk tube. Under argon protection, 0.5 mmol of styrene, 0.7 mmol of dimethylphenylsilane, and 2 mL of toluene were added. The mixture was stirred at 100 °C for 12 hours and then cooled to room temperature. 20 mg of n-hexadecane was added to the solution, and the yield was determined by gas chromatography-mass spectrometry. The catalyst was separated by centrifugation, washed three times with water and ethanol, and then dried under vacuum at 65 °C for 4 hours for use in the next catalytic cycle.

[0122] The results are as follows Figure 8 As shown, the composite catalyst (Ir@L3-3) of the present invention can be recycled more than 8 times in the olefin hydrosilylation reaction, and still maintains high product activity and the yield does not decrease significantly.

[0123] Selective experiment

[0124] 15 mg of the composite catalyst (Ir@L3-3) was added to a Schlenk tube. Under argon protection, 0.5 mmol of styrene, 0.7 mmol of dimethylphenylsilane, and 2 mL of toluene were added. The mixture was stirred at 100 °C for 12 hours. The yield was determined by gas chromatography-mass spectrometry. The yield of the dehydrosilylated product 3 was 87%, while the proportion of the completely hydrogenated product 3' was less than 5%.

[0125]

[0126] In summary, the composite catalyst provided by this invention has a large specific surface area and a hierarchical porous structure, enabling efficient catalysis of direct hydrosilylation. Furthermore, the composite catalyst can be recycled and reused, exhibiting excellent cyclic catalytic performance and significantly reducing production costs. In addition, the composite catalyst of this invention demonstrates excellent activity and regioselectivity in the hydrosilylation reaction, resulting in high reaction yields. Other substituent-substituted composite catalysts of this invention also exhibit similar effects; however, to avoid redundancy, they will not be elaborated upon further.

[0127] The present invention has been described in detail above with reference to the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. The application of a composite catalyst in the catalytic hydrosilylation reaction, characterized in that, The composite catalyst comprises iridium and a nitrogen-containing porous organic polymer; the iridium is supported in the nitrogen-containing porous organic polymer. The nitrogen-containing porous organic polymer is a random copolymer, and its general structural formula is shown in Formula I: ； Where m and n represent the molar amounts of the monomers, and the molar ratio of m to n is 1:(5~100). R 1 and R 2 are each independently selected from the group consisting of hydrogen, halogen, cyano, amino, C 2~6 alkenyl, C 2~6 alkynyl, C 1~14 alkyl, C 1~6 alkoxy, C 6~14 aryl, C 3~10 heteroaryl containing 1 to 3 heteroatoms selected from the group consisting of N, O and S; R is selected from one of the following structural formulas: 。 2. The application according to claim 1, characterized in that, The iridium content is 0.1% to 10% of the total mass of the composite catalyst.

3. The application according to claim 1, characterized in that, The molar ratio of m to n is 1:(5~20).

4. The application according to claim 1, characterized in that, R 1 and R 2 are independently selected from the group consisting of hydrogen, C 1~10 alkyl, C 1~4 alkoxy, C 6~10 aryl, C 5~10 heteroaryl containing 1 or 2 heteroatoms selected from the group consisting of N and O.

5. The application according to claim 1, characterized in that, R 1 and R 2 are independently selected from at least one of hydrogen, fluorine, chlorine, bromine, vinyl, ethynyl, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl, methoxy, ethoxy, n-propyloxy, i-propyloxy, n-butyloxy, i-butyloxy, t-butyloxy, cyclopentyl, cyclohexyl, 1-adamantyl, phenyl, 1-naphthyl, 2-furyl, 2-pyrrolyl, pyranyl or pyridyl.

6. The application according to any one of claims 1 to 5, characterized in that, The composite catalyst is prepared by the following method: The iridium precursor was prepared by mixing with a nitrogen-containing porous organic polymer and then using an impregnation method.

7. The application according to claim 6, characterized in that, The iridium precursor is selected from acetylacetone dicarbonyl iridium (I), acetylacetone bis(ethylene) iridium (I), tri(triphenylphosphine) iridium, bis(ethylene) iridium chloride, carbonyl di(triphenylphosphine) iridium chloride (I), and bis(4,6-difluorophenylpyridine-N,C 2 At least one of the following: iridium(III) pyridinecarboxylate, tri(norbornene)(acetylacetone)iridium(III), 1,5-cyclooctadiene iridium chloride dimer, bis(ethylene)iridium(I) chloride dimer, (acetylacetone)(1,5-cyclooctadiene)iridium(I), dichloro(pentamethylcyclopentadienyl)iridium(III) dimer, and tricarbonyl iridium chloride, carbonyl dihydrotri(triphenylphosphine)iridium(I).

8. The application according to claim 6, characterized in that, The steps of the impregnation method are as follows: Under inert gas protection, the iridium precursor, nitrogen-containing porous organic polymer, and solvent are mixed, heated, and stirred until the solvent is removed to obtain the final product.

9. The application according to claim 6, characterized in that, The nitrogen-containing porous organic polymer is prepared by the following method: The compound of formula II, comonomer R, organic solvent and initiator are subjected to a polymerization reaction; The structural formula of compound II is as follows: 。

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