A monophosphine polymer-embedded catalyst for olefin hydroformylation and its preparation method and application

Abstract

This invention discloses a monophosphine polymer-embedded catalyst for olefin hydroformylation, its preparation method, and its applications. This monophosphine polymer-embedded catalyst is obtained in one step via solvothermal polymerization of a vinyl-functionalized monophosphine ligand and an active metal precursor. The catalyst prepared by this invention is composed of an active metal and a monophosphine copolymer. This catalyst can both embed the active metal and achieve efficient and highly selective olefin hydroformylation reactions using CO as a carbonyl source under mild conditions. The catalyst of this invention retains the advantages of homogeneous catalysts, such as high catalytic activity and good chemoselectivity, and has a relatively simple synthesis route, relatively low production cost, and easy separation of the catalyst and product. It is suitable for olefin hydroformylation reactions, thus meeting the industrial application requirements of olefin hydroformylation reactions. Furthermore, it allows for the controllable synthesis of aldehydes or alcohols by controlling the temperature.

Description

Technical Field

[0001] This invention belongs to the field of catalytic materials, specifically relating to a single-phosphine polymer-encapsulated catalyst for olefin hydroformylation, its preparation method, and its application. Background Technology

[0002] Currently, the industrial production of alcohols is based on a multi-step process, including the hydroformylation of olefins to aldehydes, followed by the purification and hydrogenation of the aldehydes to obtain alcohols. One-pot hydroformylation, involving the reductive hydroformylation of readily available olefins and syngas, is a simple and atom-economical process for producing homologous alcohols. This process eliminates the need for energy-intensive aldehyde separation, simplifying the overall operation and reducing energy consumption, ultimately improving process economics and minimizing environmental impact.

[0003] The direct conversion of readily available olefins into high-value-added alcohols is an important yet challenging task in organic synthesis and industry. One-pot hydroformylation of olefins, achieved through temperature control, provides a simple and atom-economical method for synthesizing homologous alcohols and aldehydes. However, research on catalyzing this reaction using stable and efficient heterogeneous catalysts is still insufficient. Therefore, there is an urgent need to develop a novel, highly efficient porous organophosphorus ligand polymer catalytic material that can be effectively recycled while improving the activity and substrate versatility of the hydroformylation reaction, thereby enabling the controllable synthesis of alcohols or aldehydes from one-pot reductive hydroformylation of olefins.

[0004] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a single-phosphine polymer-encapsulated catalyst for the hydroformylation of olefins, its preparation method and application, which can realize the one-pot reductive hydroformylation reaction of olefins and controllably synthesize alcohols or aldehydes.

[0006] To achieve the above objectives, the present invention provides a monophosphine polymer-embedded catalyst for the hydroformylation of olefins. This catalyst is obtained in one step by solvothermal polymerization of a vinyl-functionalized monophosphine ligand and an active metal precursor; the active metal in the active metal precursor accounts for 0.1–10.0% of the total weight of the monophosphine polymer-embedded catalyst; wherein the structure of the vinyl-functionalized monophosphine ligand is selected from any one or more of the following:

[0007]

[0008] Preferably, the active metal precursor is any one or more of cobalt, ruthenium, or platinum.

[0009] A second objective of this invention is to provide a method for preparing the aforementioned monophosphine polymer-encapsulated catalyst, the method comprising:

[0010] (1) Under an inert gas protective atmosphere, the monophosphine ligand containing vinyl functional groups and the active metal precursor are co-dissolved in a first organic solvent at a molar ratio of 10 to 1000:1, and the reaction is stirred at 20 to 80°C for 1 to 4 hours to obtain the coordination product.

[0011] (2) Under an inert gas atmosphere, the coordination product and the free radical initiator are co-dissolved in a second organic solvent, and the polymerization reaction is carried out in a high-pressure reactor at 40-150°C for 20-25 hours. After washing, the organic solvent is removed under reduced pressure at 20-50°C to obtain a catalyst with a monophosphine ligand polymer embedded in it.

[0012] Preferably, the active metal precursor is selected from any one or more of cobalt acetate, cobalt nitrate, cobalt chloride, cobalt sulfate, cobalt acetylacetonate, cobalt oxalate, bis(pentamethylcyclopentadiene)cobalt, hexaamminecobalt trichloride, cobalt octacarbonyl, ruthenium trichloride, ruthenium acetate, bis(triphenylphosphine)dicarbonylruthenium(II) chloride, and platinum nitrate.

[0013] Preferably, the molar ratio of the vinyl-functionalized monophosphine ligand to the free radical initiator is (10-100):1.

[0014] Preferably, the free radical initiator is selected from any one of azobisisobutyronitrile, hydrogen peroxide, ammonium persulfate, potassium persulfate, benzoyl peroxide, and methyl ethyl ketone peroxide; or / and, the first organic solvent and the second organic solvent are each independently selected from any one or more of ethanol, 1,4-dioxane, tetrahydrofuran, ethylene glycol dimethyl ether, ethyl acetate, N,N-dimethylformamide, dimethyl sulfoxide, n-hexane, toluene, anisole, dichloromethane, and chloroform.

[0015] Preferably, for three identically substituted monophosphine ligands, the method for preparing the vinyl-functionalized monophosphine ligand comprises:

[0016] In an inert gas environment at -78°C, a hexane solution of n-butyllithium was added dropwise to an anhydrous tetrahydrofuran solution of bromovinylbenzene, the solution was stirred, and then an anhydrous tetrahydrofuran solution of phosphorus trichloride was added dropwise. The mixture was stirred at -78°C, and then the system was restored to room temperature and the reaction was allowed to proceed overnight to obtain a monophosphine ligand containing vinyl functionalized groups.

[0017] Alternatively, under an inert gas environment at -50°C, a hexane solution of n-butyllithium is added dropwise to an anhydrous tetrahydrofuran solution of methyltriphenylphosphine bromide, the solution is stirred, and then an anhydrous tetrahydrofuran solution of 3-bromo-4-substituted benzaldehyde is slowly added dropwise. The mixture is stirred at 0°C. After the reaction is complete, post-treatment is performed, the obtained product is dissolved in tetrahydrofuran, and the solution is added dropwise to magnesium shavings and reacted to obtain a monophosphine ligand containing vinyl functionalized groups.

[0018] More preferably, the 3-bromo-4-substituted benzaldehyde is selected from 3-bromo-4-fluorobenzaldehyde, 3-bromo-4-methylbenzaldehyde, or 3-bromo-4-methoxybenzaldehyde.

[0019] Preferably, for different substituted monophosphine ligands, the method for preparing the vinyl-functionalized monophosphine ligand includes:

[0020] In an inert gas environment at -78°C, a hexane solution of n-butyllithium was added dropwise to an anhydrous tetrahydrofuran solution of bromovinylbenzene, and the solution was stirred. Then, an anhydrous tetrahydrofuran solution of phosphorus trichloride was added dropwise. The mixture was stirred continuously at -78°C, and then the system was brought to room temperature and the reaction was allowed to proceed overnight. The hexane solution of n-butyllithium was then added dropwise to the above solution, and the solution was stirred. Then, an anhydrous tetrahydrofuran solution of bromobenzene was added dropwise. The mixture was stirred continuously at -78°C, and then the system was brought to room temperature and the reaction was allowed to proceed overnight to obtain vinyl-functionalized monophosphine ligands containing benzene ring-substituted groups.

[0021] A third objective of this invention is to provide the application of the aforementioned monophosphine polymer-embedded catalyst in the hydroformylation reaction of medium- and long-chain α-olefins to prepare higher alcohols and higher aldehydes, wherein the medium- and long-chain α-olefins are olefins with a total number of 5 or more carbon atoms.

[0022] Preferably, the medium-to-long-chain α-olefin is selected from olefins with a carbon chain length of 5 to 15 or olefins with five to eight-membered rings. Specifically, the olefin with a carbon chain length of 5 to 15 may be selected from 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tetracene, 1-tetradecene, or 1-pentadene.

[0023] Preferably, the olefin with a total of 5 or more carbon atoms contains an ester group or a silane group on its carbon chain.

[0024] Preferably, the reaction conditions for the hydroformylation reaction to prepare higher alcohols and higher aldehydes are as follows: in a batch reactor, the syngas volume ratio is CO:H2 = 1-3:1, the reaction pressure is 0.1-10.0 MPa, the reaction temperature is 40-200℃, and the reaction solvent is selected from any one or more of cyclohexane, toluene, 1,4-dioxane, tetrahydrofuran, or p-xylene. The olefin and syngas undergo hydroformylation under the catalysis of the monophosphine polymer-embedded catalyst to generate an aldehyde or alcohol with one more carbon atom than the medium- or long-chain α-olefin; when the reaction temperature is above 160℃, an alcohol with one more carbon atom than the medium- or long-chain α-olefin is generated; when the reaction temperature is below 160℃, an aldehyde with one more carbon atom than the medium- or long-chain α-olefin is generated.

[0025] More preferably, when the reaction temperature is between 160 and 200°C, an alcohol with one more carbon atom than a medium- or long-chain α-olefin is generated; when the reaction temperature is between 40 and 150°C, an aldehyde with one more carbon atom than a medium- or long-chain α-olefin is generated.

[0026] The monophosphine polymer-encapsulated catalyst for olefin hydroformylation of the present invention, its preparation method, and its application have the following advantages:

[0027] The catalyst prepared in this invention is composed of an active metal and a monophosphine copolymer. This catalyst can both encapsulate the active metal and achieve efficient and highly selective olefin hydroformylation reactions using CO as a carbonyl source under mild conditions. The active metal component forms chemical coordination bonds with phosphorus (P) in the polymer, resulting in a highly dispersed state of the active component, thus giving the catalyst high activity and high stability. This catalyst retains the advantages of homogeneous catalysts, such as high catalytic activity and good chemical selectivity, and has a relatively simple synthetic route, relatively low production cost, and easy separation of the catalyst and product. It is suitable for olefin hydroformylation reactions, thus meeting the industrial application requirements of olefin hydroformylation reactions. Furthermore, it allows for the controlled synthesis of aldehydes or alcohols by controlling the temperature.

[0028] The monophosphine copolymer of the present invention is generated by solvothermal polymerization of one or more vinyl-functionalized monophosphine ligand monomers through controlled input ratio, resulting in a large specific surface area (355.270 m²). 2 ·g -1 (and copolymers with various types and sizes of pore structures.) Attached Figure Description

[0029] Figure 1 The image shows the BET characterization of catalyst A in Example 1.

[0030] Figure 2 The image shows the TGA characterization of catalyst A in Example 1.

[0031] Figure 3The images show the HR-TEM characterization diagram (a) and EDX maps (b) of catalyst A in Example 1.

[0032] Figure 4 XRD characterization diagram of catalyst A in Example 1. Detailed Implementation

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] It should be noted that: for conditions not specifically specified in the examples, standard conditions or conditions recommended by the manufacturer should be followed. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0035] In this invention, all features defined by numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are used for simplicity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible secondary ranges and individual numerical values ​​(including integers and fractions) within those ranges.

[0036] The features mentioned in this invention can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification, provided that there is no contradiction in the combination of these features. Each feature disclosed in the specification can be replaced by any alternative feature that provides the same, equivalent, or similar purpose. Therefore, unless otherwise specified, the disclosed features are merely general examples of equivalent or similar features.

[0037] In this invention, unless otherwise stated, the term "medium- and long-chain α-olefin" refers to an olefin with a total number of 5 or more carbon atoms, preferably an olefin with a total number of 5 to 15 carbon atoms.

[0038] Example 1

[0039] A monophosphine polymer-encapsulated catalyst for olefin hydroformylation is prepared as follows:

[0040] A solution of n-butyllithium in n-hexane (2.5 M, 12.6 mL, 31.5 mmol) was added dropwise over 20 minutes to a solution of p-bromovinylbenzene (6.04 g, 33 mmol) in anhydrous tetrahydrofuran (40 mL). The solution was stirred for 1 hour, and then phosphorus trichloride (1.37 g, 10 mmol) dissolved in anhydrous tetrahydrofuran (5 mL) was added dropwise over 5 minutes. The mixture was stirred at -78 °C for another 1 hour, and then the system was allowed to return to room temperature and the reaction was allowed to proceed overnight.

[0041] After the reaction was complete, the mixture was quenched with 2M HCl solution. The mixture was extracted three times with ethyl acetate and water. The combined organic phases were dried over anhydrous Na2SO4 and concentrated under reduced pressure. The residue was purified by flash column chromatography on silica gel using an ethyl acetate-petroleum ether mixture as the eluent to obtain the desired monophosphine ligand L1 as a white solid.

[0042] Under an inert atmosphere, monophosphine ligand L1 (340.0 mg, 1 mmol) and octacarbonyl dicobalt (34.1 mg, 0.1 mmol) were dissolved in 10 mL of tetrahydrofuran (THF) and stirred at room temperature for 2 h to obtain the coordination product. Under an inert atmosphere, the coordination product and the free radical initiator azobisisobutyronitrile (16.4 mg, 0.1 mmol) were added to 10 mL of tetrahydrofuran. The resulting reaction solution was transferred to a hydrothermal reactor and stirred at room temperature for 0.5 h. Then, it was heated to 100 °C in a forced-air drying oven and allowed to stand for 24 h.

[0043] After the polymerization reaction was completed, the resulting brown solid was filtered, washed with tetrahydrofuran (20 mL × 3), and dried under vacuum at 60 °C for 12 h to obtain a cobalt-based catalyst material embedded with a monophosphine ligand polymer, denoted as catalyst A.

[0044]

[0045] Example 2

[0046] A monophosphine polymer-encapsulated catalyst for olefin hydroformylation differs from Example 1 only in that:

[0047] Weigh out 340 mg of monophosphine ligand L2 to replace 340 mg of L1, weigh out 3.41 mg of octacarbonyl dicobalt to replace 34.1 mg of octacarbonyl dicobalt, and weigh out 1.64 mg of azobisisobutyronitrile to replace 16.4 mg of azobisisobutyronitrile.

[0048] The rest is the same as in Example 1. The obtained monophosphine ligand polymer is used to embed cobalt-based catalytic material, which is referred to as catalyst B.

[0049]

[0050] The preparation method of monophosphine ligand L2 is basically the same as that of monophosphine ligand L1 in Example 1, except that:

[0051] m-bromovinylbenzene was used instead of p-bromovinylbenzene.

[0052] Example 3

[0053] A monophosphine polymer-encapsulated catalyst for olefin hydroformylation differs from Example 1 only in that:

[0054] Weigh 409 mg of monophosphine ligand L3 to replace 340 mg of L1, and the rest is the same as in Example 1. The resulting monophosphine ligand polymer is used to encapsulate cobalt-based catalytic material, which is denoted as catalyst C.

[0055]

[0056] The preparation method of monophosphine ligand L3 is as follows:

[0057] First, under an argon atmosphere at -50°C, a solution of n-butyllithium in hexane (2.5 M, 8.4 mL, 31.5 mmol) was added dropwise over 60 minutes to a solution of methyltriphenylphosphine bromide (4.06 g, 20 mmol) in anhydrous tetrahydrofuran (100 mL). The solution was stirred for 1 h, and then 3-bromo-4-fluorobenzaldehyde (4.06 g, 20 mmol) dissolved in anhydrous tetrahydrofuran (100 mL) was slowly added dropwise. The mixture was stirred at 0°C for another 1 h. After the reaction was complete, 50 mL of NH4Cl solution was added. The organic phase was extracted three times with ethyl acetate. The mixture was then filtered and purified by silica gel chromatography (eluent: petroleum ether).

[0058] The above product was dissolved in 60 mL of THF, and magnesium filings (0.51 g, 21 mmol) were added dropwise over 1 h, followed by a reaction time of 4 h. The residue was purified by flash column chromatography on silica gel using an ethyl acetate-petroleum ether mixture as the eluent to obtain the desired monophosphine ligand L3 as a white solid.

[0059] Example 4

[0060] A monophosphine polymer-encapsulated catalyst for olefin hydroformylation differs from Example 1 only in that:

[0061] Weigh out 51.8 mg (0.20 mmol) of cobalt acetylacetonate to replace 34.1 mg of cobalt octacarbonyl, and the rest is the same as in Example 1. The resulting monophosphine ligand polymer encapsulates the cobalt-based catalytic material, which is denoted as catalyst D.

[0062] Example 5

[0063] A monophosphine polymer-encapsulated catalyst for olefin hydroformylation differs from Example 1 only in that:

[0064] 113.7 mg of octacarbonyl dicobalt was weighed to replace 34.1 mg of octacarbonyl dicobalt. The polymerization temperature was 40 °C. The rest was the same as in Example 1. The resulting monophosphine ligand polymer encapsulated the cobalt-based catalyst material and was denoted as catalyst E.

[0065] Example 6

[0066] A monophosphine polymer-encapsulated catalyst for olefin hydroformylation differs from Example 1 only in that:

[0067] The coordination process was carried out at a stirring temperature of 80°C for 1 hour. The solvent N,N-dimethylformamide (DMF) was used instead of tetrahydrofuran. The rest was the same as in Example 1. The resulting monophosphine ligand polymer encapsulated the cobalt-based catalyst material, which was denoted as catalyst F.

[0068] Example 7

[0069] A monophosphine polymer-encapsulated catalyst for olefin hydroformylation differs from Example 1 only in that:

[0070] The stirring temperature during the coordination process was 20°C. During the polymerization process, the hydrothermal reactor was heated to 140°C in a forced-air drying oven and allowed to stand for 24 hours. The rest was the same as in Example 1. The obtained monophosphine ligand polymer encapsulated cobalt-based catalyst material and was denoted as catalyst G.

[0071] Example 8

[0072] A monophosphine polymer-encapsulated catalyst for olefin hydroformylation differs from Example 1 only in that:

[0073] Weigh out 26.0 mg of cobalt chloride to replace 34.1 mg of octacarbonyl dicobalt, select hydrogen peroxide to replace azobisisobutyronitrile as the free radical initiator, and the rest is the same as in Example 1. The resulting monophosphine ligand polymer encapsulates the cobalt-based catalytic material and is denoted as catalyst H.

[0074] Example 9

[0075] A monophosphine polymer-encapsulated catalyst for olefin hydroformylation differs from Example 1 only in that:

[0076] Weigh out 36.6 mg of cobalt nitrate instead of 34.1 mg of octacarbonyl dicobalt, and use ethanol as the solvent instead of tetrahydrofuran. The rest is the same as in Example 1. The resulting monophosphine ligand polymer encapsulates the cobalt-based catalytic material and is denoted as Catalyst I.

[0077] Example 10

[0078] Weigh 41.4 mg of ruthenium trichloride to replace 34.1 mg of cobalt octacarbonyl, and the rest is the same as in Example 1. The resulting monophosphine ligand polymer encapsulates the cobalt-based catalytic material, which is denoted as catalyst J.

[0079] Example 11

[0080] A monophosphine polymer-encapsulated catalyst for olefin hydroformylation differs from Example 1 only in that:

[0081] Weigh out 73.8 mg of platinum nitrate to replace 34.1 mg of cobalt octacarbonyl, and the rest is the same as in Example 1. The resulting monophosphine ligand polymer encapsulates the cobalt-based catalytic material, which is denoted as catalyst K.

[0082] Experimental Example 1: Structural Characterization

[0083] 1. BET representation

[0084] The structural characteristics of catalyst A in Example 1 were evaluated at 77 K using a nitrogen adsorption isotherm, which showed a reversible type IV adsorption isotherm and a mesoporous structure with pore sizes mainly distributed in the range of 3–10 nm.

[0085] 2. TGA characterization

[0086] TGA analysis curves show that catalyst A in Example 1 exhibits good thermal stability, with a weight loss of only 3.28% at a high temperature of 372°C.

[0087] 3. Characterization using HR-TEM and EDX maps

[0088] TEM revealed that catalyst A used in Example 1 was porous and amorphous, and no Co nanoparticles were detected in the HR-TEM images, indicating that Co species were highly dispersed in the polymer. Furthermore, EDX spectra showed that C, P, and Co elements were uniformly distributed in catalyst A used in Example 1, with the presence of Co indicating the formation of encapsulated, isolated Co species within the polymer.

[0089] 4. XRD characterization

[0090] XRD analysis showed that no characteristic peaks of Co were detected in the XRD image of catalyst A used in Example 1, indicating that Co species were highly dispersed in the polymer.

[0091] Performance Evaluation of Experiment Example 2

[0092] The catalysts A to K prepared in Examples 1 to 11 above, along with the hydroformylation reaction conditions, were used for the hydroformylation of medium- and long-chain α-olefins to illustrate the catalytic performance of different catalysts and reaction conditions in the hydroformylation of medium- and long-chain α-olefins to generate higher alcohols and higher aldehydes by temperature control.

[0093] 1. Catalytic performance

[0094] 1) Effects of different monophosphine ligands, metal precursors, and catalysts synthesized at different temperatures on the catalytic performance of hydroformylation to alcohol synthesis.

[0095] 50 mg of the catalyst (catalyst A to catalyst K) prepared in the embodiments of the present invention, 0.5 mmol of 1-octene, and 3 mL of tetrahydrofuran (THF) were placed in a 100 mL batch reactor. The gas in the reactor was replaced three times with 1 MPa of syngas (CO / H2 = 1:1), and then 4 MPa of syngas (CO / H2 = 1:1) was introduced. The reactor was stirred at 170 °C for 12 hours.

[0096] After the reaction was completed, the reaction vessel was cooled to room temperature, and biphenyl was added as an internal standard. The reaction solution was analyzed by gas chromatography using an HP-7890N equipped with an HP-5 capillary column and an FID detector. The results are shown in Table 1.

[0097] Table 1 shows the results of the catalyst used in the examples for the catalytic synthesis of 1-octene hydroformylation alcohol at 170°C.

[0098]

[0099] 2) The effect of different hydroformylation reaction conditions on the catalytic performance of hydroformylation to aldehyde synthesis is basically the same as that in 1) above, except that:

[0100] a) Hydroformylation of different catalysts A to I at different temperatures;

[0101] b) Hydroformylation of catalyst A in different solvents.

[0102] The test results are shown in Tables 2 and 3.

[0103] Table 2 Results of the catalytic synthesis of aldehydes via 1-octene hydroformylation under different temperatures and solvents.

[0104] catalyst reaction temperature reaction solvent Conversion rate (%) Aldehyde selectivity (%) Aldehyde yield (%) A 40℃ THF 15 89 13 A 150℃ THF 96 55 53 A 140℃ THF 91 79 72 A 140℃ Toluene 79 45 36 B 140℃ THF 93 77 72 C 140℃ THF 79 79 62 D 140℃ THF 13 5 7 E 140℃ THF 53 35 19 F 140℃ THF 69 66 46 G 140℃ THF 89 79 70 H 140℃ THF 59 73 43 I 140℃ THF 55 69 40 G 140℃ THF 90 78 70 K 140℃ THF 88 66 58

[0105] Table 3 Results of the catalytic synthesis of alcohols via 1-octene hydroformylation under different solvents and temperatures.

[0106] catalyst reaction temperature reaction solvent Conversion rate (%) Alcohol selectivity (%) Alcohol yield (%) A 160℃ THF 96 79 76 A 170℃ THF 98 91 89 A 170℃ Toluene 44 53 47 A 200℃ THF 99 85 84

[0107] As can be seen from Tables 1 to 3, the catalyst provided by the present invention exhibits good catalytic performance in controlling the hydroformylation of long-chain α-olefins to generate higher alcohols and higher aldehydes by changing the temperature.

[0108] 2. Cyclic stability

[0109] Taking catalyst A prepared in Example 1 as an example, the reusability of the cobalt-based catalyst embedded with a single phosphine ligand polymer in the catalytic hydroformylation reaction of 1-octene is illustrated.

[0110] Similar to the hydroformylation reaction in 1) above, the reaction data for catalyst reuse are shown in Table 4.

[0111] Table 4. Reusability of Catalyst A in Example 1

[0112] Number of times to reuse Conversion rate (%) Alcohol yield (%) first 98 87 The second 97 85 The third 99 83 Fourth 99 85

[0113] As can be seen from Table 4, the catalyst prepared by this invention can be reused at least four times, and its catalytic activity can still be maintained at a high level.

[0114] 3. Substrate adaptability

[0115] Taking catalyst A prepared in Example 1 as an example, the catalytic performance of cobalt-based catalysts embedded with monophosphine ligand polymers in catalyzing the hydroformylation reactions of different olefins is illustrated.

[0116] The reaction is essentially the same as the hydroformylation reaction in 1) above. The only difference is that 0.5 mmol of 1-octene is replaced by 0.5 mmol of a different olefin substrate; otherwise, the reaction is identical to that of 1-octene. The structures are shown in Tables 5 and 6 below.

[0117] Table 5 Catalytic performance of catalyst A in the hydroformylation of different olefins to alcohols at 170℃

[0118]

[0119] Note: l / b in the table represents the positive and negative ratio of the generated product, and the same applies to the following tables.

[0120] Table 6. Catalytic performance of catalyst A in the hydroformylation of different olefins to aldehydes at 140℃

[0121]

[0122] As can be seen from Tables 5 and 6, the catalytic materials prepared in this invention exhibit excellent catalytic activity and good applicability when applied to the hydroformylation reactions of different aliphatic olefins.

[0123] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A method for preparing a single-phosphine polymer-encapsulated catalyst, characterized in that, The method includes: (1) Under an inert gas atmosphere, a monophosphine ligand containing vinyl functionalization and an active metal precursor are co-dissolved in a first organic solvent at a molar ratio of 10~100:1 and stirred at 20~80℃ for 1~4 h to obtain a coordination product. (2) Under an inert gas atmosphere, the coordination product and the free radical initiator are co-dissolved in a second organic solvent, and the polymerization reaction is carried out in a high-pressure reactor at 40~150℃ for 20~25 h. After washing, the organic solvent is removed under reduced pressure at 20~50℃ to obtain a catalyst embedded with a monophosphine ligand polymer. The structure of the vinyl-functionalized monophosphine ligand is selected from any one or more of the following: , , ; The active metal precursor is any one or more of cobalt, ruthenium, or platinum.

2. The preparation method according to claim 1, characterized in that, The active metal precursor is selected from any one or more of cobalt acetate, cobalt nitrate, cobalt chloride, cobalt sulfate, cobalt acetylacetone, cobalt oxalate, bis(pentamethylcyclopentadiene)cobalt, hexaamminecobalt trichloride, cobalt octacarbonyl, ruthenium trichloride, ruthenium acetate, bis(triphenylphosphine)dicarbonylruthenium(II) chloride, and platinum nitrate.

3. The preparation method according to claim 1, characterized in that, The molar ratio of the vinyl-functionalized monophosphine ligand to the free radical initiator is (10~100):

1.

4. The preparation method according to claim 1, characterized in that, The free radical initiator is selected from any one of azobisisobutyronitrile, ammonium persulfate, potassium persulfate, benzoyl peroxide, and methyl ethyl ketone peroxide; Or / and, the first organic solvent and the second organic solvent are each independently selected from any one or more of ethanol, 1,4-dioxane, tetrahydrofuran, ethylene glycol dimethyl ether, ethyl acetate, N,N-dimethylformamide, dimethyl sulfoxide, n-hexane, toluene, anisole, dichloromethane and chloroform.

5. The application of the monophosphine polymer-encapsulated catalyst obtained by any one of the preparation methods described in claims 1 to 4 in the hydroformylation reaction of medium- and long-chain α-olefins to prepare higher alcohols and higher aldehydes, characterized in that, The medium- and long-chain α-olefins are olefins with a total number of 5 or more carbon atoms.

6. The application according to claim 5, characterized in that, The medium- and long-chain α-olefins are selected from olefins with a carbon chain length of 5 to 15 or olefins with five to eight-membered rings.

7. The application according to claim 5, characterized in that, The olefins with a total of 5 or more carbon atoms contain ester groups or silane groups on their carbon chains.

8. The application according to claim 5, characterized in that, The reaction conditions for the hydroformylation reaction to prepare higher alcohols and higher aldehydes are as follows: In a batch reactor, the syngas volume ratio is CO:H2 = 1~3:1, the reaction pressure is 0.1~10.0 MPa, the reaction temperature is 40~200℃, and the reaction solvent is selected from any one or more of cyclohexane, toluene, 1,4-dioxane, tetrahydrofuran, or p-xylene. The olefin and syngas undergo hydroformylation under the catalysis of the monophosphine polymer-embedded catalyst to produce an aldehyde or alcohol with one more carbon than the medium- and long-chain α-olefin. When the reaction temperature is above 160°C, an alcohol with one more carbon atom than a medium- or long-chain α-olefin is produced. When the reaction temperature is less than 160°C, an aldehyde with one more carbon atom than a medium-to-long-chain α-olefin is generated.

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