Pd-coordinated P-ion-containing liquid catalyst, preparation method thereof and application of Pd-coordinated P-ion-containing liquid catalyst in olefin hydroesterification reaction

Abstract

The invention belongs to the technical field of olefin hydroesterification reaction and catalysts thereof, and particularly relates to a Pd-coordinated liquid catalyst containing P ions, a preparation method of the Pd-coordinated liquid catalyst and application of the Pd-coordinated liquid catalyst in olefin hydroesterification reaction. The preparation method of the Pd-coordinated P-ion-containing liquid catalyst comprises the following steps: mixing a zwitter-ion precursor A and a zwitter-ion precursor B for reaction to obtain zwitter-ion solid powder; dissolving the zwitterionic solid powder in methanol, dropwise adding an anion precursor, and reacting to obtain an ionic liquid; adding a deprotonation reagent into the ionic liquid, adding a P-containing precursor after reaction, and reacting to obtain P-containing ionic liquid; the method comprises the following steps: dissolving a Pd compound in methanol, adding a P-ion-containing liquid, and reacting to obtain a Pd coordinated P-ion-containing liquid; the Pd-coordinated P-ion-containing liquid catalyst provided by the invention is used for preparing organic carboxylic ester, the reaction activity and selectivity are relatively high, the recovery of the catalyst is realized, and the space structure and the electronic state of the catalyst are adjustable.

Description

Technical Field

[0001] The invention belongs to the technical field of olefin hydroesterification reaction and catalysts thereof, and particularly relates to a Pd-coordinated P-containing ionic liquid catalyst and a preparation method thereof and application thereof in olefin hydroesterification reaction. Background Art

[0002] Esters are simple functional groups that are commonly found in natural and synthetic compounds. Esters are usually synthesized by enzymes in nature, while chemists can use acidic catalysts or condensation reagents to obtain esters from corresponding carboxylic acids and alcohols. Using new synthetic methods to insert ester groups into the desired position of the target molecule is also an important type of reaction for synthesizing esters. Olefins are substrates that can be synthesized by metal-catalyzed hydroesterification using carbon monoxide and alcohols. Since Reppe discovered this reaction, the method has been greatly improved through continuous research and optimization, making it possible to synthesize esters from olefins in industrial applications. Homogeneous catalytic systems composed of palladium, phosphorus ligands and acids have attracted widespread attention due to their good substrate adaptability and excellent catalytic performance. They are usually used as catalyst systems for olefin hydroesterification reactions, such as PdCl2 / PPh3 / CuCl2, [Pd(dtbpx)(dba)], [Pd(PPh3)2(olefin)], [PdCl2(dppp)] and other catalyst systems. Of course, there are still some problems in the practical application of these catalytic systems, such as the difficulty in simply separating and reusing the catalysts.

[0003] Room temperature ionic liquids as a medium for the hydroesterification of alcohols have unique product selectivity and better catalytic activity. Under the same reaction conditions, ionic liquids can form complexes with the ligands involved in the reaction to promote the reaction. They can even directly catalyze the reactants to generate the corresponding esters, and make product separation simple, which is convenient for the reuse of catalysts. Zim et al. m The hydroesterification reaction of styrene derivatives was investigated in a two-phase system formed by ][BF4] and isopropanol. The results showed that the use of ionic liquids can make it easy to separate the product from the catalyst system. Therefore, ionic liquids can replace traditional organic solvents in olefin hydroesterification reactions and improve the activity and selectivity of the catalyst, making the product easy to separate. At the same time, the selection of suitable ligands can not only improve the activity of the catalyst, but also fix the catalyst in the form of a complex in the ionic liquid, which can better solve the problems of catalyst loss and reuse.

[0004] CN201010595461.X discloses the use of ionic liquid acidic ionic liquid to replace methanesulfonic acid for hydroesterification reaction to reduce corrosion to the reactor. However, these studies still require the addition of additional P ligands and Pd compounds to jointly achieve the hydroesterification reaction of olefins, and the recovery and reuse effect of the precious metal Pd is poor.

[0005] CN201810811082.6 discloses a catalytic system for synthesizing methyl propionate and an application method thereof. When preparing methyl propionate, carbonates, lithium halides or transition metal chlorides are used as catalyst promoters, and imidazole ionic liquids are used to consume the water generated in the reaction to promote the reaction in the positive direction. However, the reaction needs to be carried out at a higher temperature, which places higher requirements on the equipment, and the active metal Ru complex and the ionic liquid are two independent compounds, which is not conducive to the separation of the products. Summary of the invention

[0006] The technical problem to be solved by the present invention is to overcome the above-mentioned defects of the prior art and provide a Pd-coordinated P-containing ionic liquid catalyst, which is used to prepare organic carboxylic acid esters, has high reaction activity and selectivity, realizes catalyst recycling and reuse, and the spatial structure and electronic state of the catalyst are adjustable.

[0007] The method for preparing the Pd-coordinated P-containing ionic liquid catalyst of the present invention comprises the following steps:

[0008] (1) After mixing zwitterion precursor A and zwitterion precursor B, stirring and reacting at 40-90° C. for 2-12 hours to obtain a zwitterion solid crude product, filtering, washing, and drying to obtain a zwitterion solid powder;

[0009] (2) dissolving the zwitterionic solid powder in methanol, adding an anionic precursor dropwise, and reacting at 30-80° C. for 1-12 h to obtain an ionic liquid;

[0010] (3) adding a deprotonating agent to the ionic liquid, reacting at -50-0°C for 30-120 min, adding a P-containing precursor, reacting at -78-0°C for 2-12 h, and obtaining a P-containing ionic liquid;

[0011] (4) dissolving the Pd compound in methanol, adding the P-containing ionic liquid under stirring conditions, and reacting at 40-120° C. for 4-8 hours to obtain the Pd-coordinated P-containing ionic liquid; the molar amount of Pd to the molar amount of P is (1-5):(10-100).

[0012] In step (1), the zwitterion precursor A is one of 1-methylimidazole, 1-butylimidazole, benzimidazole, and pyridine; the zwitterion precursor B is one of propane sultone, butane sultone, and bromobutylene. The solvent used for washing in step (1) is one of toluene, ether, n-hexane, nonane, methanol, and deionized water, and the drying temperature is 60-120°C.

[0013] In step (1), the molar ratio of zwitterionic precursor A to zwitterionic precursor B is (1-5): (0.5-1).

[0014] In step (2), the anion precursor is one of HCl, NaBF6, CH3SO3H, and H2SO4.

[0015] In step (3), the deprotonating agent is one of n-butyl lithium, butyl aluminum, and metallic lithium; and the P-containing precursor is one of PPh2Cl, PPh2OCH3, and HPPh2.

[0016] In step (3), the molar ratio of the ionic liquid to the deprotonating agent is (1-5):(0.1-1); the molar ratio of the ionic liquid to the P-containing precursor is (1-5):(0.1-2).

[0017] The Pd compound in step (4) is one of Pd(OAc)2, PdCl2, and bis(dibenzylideneacetone)palladium Pd(dba)2.

[0018] A Pd-coordinated P-containing ionic liquid catalyst is prepared by the preparation method.

[0019] Application of Pd-coordinated P-containing ionic liquid catalyst in olefin hydroesterification reaction: alcohol, Pd-coordinated P-containing ionic liquid catalyst and acid auxiliary agent are mixed, terminal olefin is added, pressurized, heated and reacted. The terminal olefin is one of ethylene, propylene, butylene, butadiene and styrene. The alcohol is one of methanol, ethanol, ethylene glycol and glycerol, and the alcohol compound is also used as a solvent of the reaction system. The acid auxiliary agent is one of methanesulfonic acid, p-toluenesulfonic acid and sulfuric acid. The gas used for pressurization is CO or a mixture of CO and N2, and the mass purity of the gas used is 90%-100%.

[0020] The molar ratio of H in the acid auxiliary agent to Pd in ​​the Pd-coordinated P-containing ionic liquid catalyst is (1-50): (0.5-5), the single-pot addition amount of terminal olefin is 0.05mol-10mol, the pressure is increased to 1-10Mpa, the temperature is increased to 50-180°C, and the reaction is carried out for 2-10h.

[0021] Specifically, the use of the Pd-coordinated P-containing ionic liquid catalyst in the olefin hydroesterification reaction comprises the following steps:

[0022] (1) Zwitterion precursor A and zwitterion precursor B are placed in a 100 mL round-bottom flask, stirred and reacted at 40-90° C. for 2-12 h to obtain a zwitterion white solid crude product, which is filtered and repeatedly washed with a detergent to remove non-ionic residues, and dried at 60-120° C. to obtain a zwitterion solid powder.

[0023] (2) After dissolving the zwitterionic solid powder in methanol, an anionic precursor is added dropwise, and the reaction is carried out at 30-80° C. for 1-12 hours to obtain an ionic liquid, wherein the molar ratio of the zwitterionic precursor A to the zwitterionic precursor B is (1-5): (0.5-1).

[0024] (3) Under anhydrous and oxygen-free conditions, a deprotonating agent is added to the ionic liquid, the reaction is carried out at -50-0°C for 30-120 min, a P-containing precursor is added, and the reaction is carried out at -78-0°C for 2-12 h to obtain a P-containing ionic liquid, wherein the molar ratio of the ionic liquid to the deprotonating agent is (1-5):(0.1-1); the molar ratio of the ionic liquid to the P-containing precursor is (1-5):(0.1-2).

[0025] (4) dissolving the Pd compound in methanol, adding the P-containing ionic liquid under stirring conditions, and reacting at 40-120° C. for 4-8 hours to obtain the Pd-coordinated P-containing ionic liquid; the molar amount of Pd to the molar amount of P is (1-5):(10-100).

[0026] Taking alkyl imidazole as an example, the reaction route of the above four steps is:

[0027]

[0028] (5) Add alcohol with a purity of 90% to 100%, a Pd-coordinated P-containing ionic liquid catalyst, and an acid auxiliary agent into a reaction kettle, seal it, and then charge it with terminal olefins. Then, pressurize the reaction kettle to 1-10 MPa with a purity of 90% to 100% CO or a mixture of CO and N2, raise the temperature to 50-180° C., and react for 2-10 hours. The ratio of the molar number of H in the acid auxiliary agent to the molar number of Pd in ​​the Pd-coordinated P-containing ionic liquid catalyst is (1-50):(0.5-5).

[0029] The present invention discloses a method for generating an organic carboxylic acid ester by reacting terminal olefins, CO and an alcohol compound under the action of a catalyst composed of a P ion liquid, a Pd compound and an acid auxiliary agent. The present invention has the advantages of mild reaction conditions, a wide range of raw material applications, and high product selectivity. Compared with the current hydroesterification reaction, the catalyst system used has the advantages of low equipment corrosion, easy product separation, and catalyst reusability, and is a catalyst with great industrial application prospects.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) The Pd-coordinated P-containing ionic liquid catalyst prepared by the method of the present invention has an adjustable structure. The spatial structure and electronic state of the ionic liquid can be adjusted according to the requirements of the reaction to optimize the reaction results.

[0032] (2) When the Pd-coordinated P-containing ionic liquid catalyst prepared by the present invention is used in the olefin hydroesterification reaction, the Pd-P ionic liquid synergistically provides active sites, and the reaction activity and selectivity are both high.

[0033] (3) When the Pd-coordinated P-containing ionic liquid catalyst prepared by the present invention is used in the hydroesterification reaction of olefins, the ionic liquid acts as an acid auxiliary and a solvent at the same time, which is beneficial to the separation of the catalyst system from the reaction raw materials and products, reduces the separation energy consumption, and realizes the recovery and reuse of the catalyst. DETAILED DESCRIPTION

[0034] The present invention will be further described below in conjunction with specific embodiments.

[0035] In the following examples and comparative examples, the mass purity of the alcohol is 90%-100%, the mass purity of CO or the mixed gas of CO and N2 is 90%-100%, and the other chemical reagents used are all commercially available products, and the equipment used is all existing equipment. H:Pd refers to the ratio of the molar number of H in the acid auxiliary agent to the number of Pd in ​​the N-heterocarbene Pd complex.

[0036] Example 1

[0037] The application of the Pd-coordinated P-containing ionic liquid catalyst in the olefin hydroesterification reaction comprises the following steps:

[0038] (1) 0.2 mol of 1-methylimidazole and 0.2 mol of butane sultone were placed in a 100 mL round-bottom flask and stirred at 40° C. for 10 h to obtain a zwitterionic white solid crude product. The product was filtered and repeatedly washed with ether to remove non-ionic residues. The product was then vacuum dried at 80° C. to obtain a zwitterionic solid powder.

[0039] (2) 0.1 mol of zwitterionic solid powder was transferred into a flask, dissolved with methanol, and then 10 mol of HCl was added dropwise. The mixture was reacted at 60° C. for 6 h to obtain an ionic liquid.

[0040] (3) Under anhydrous and oxygen-free conditions, 0.1 mol of n-butyl lithium was added to 0.2 mol of ionic liquid, and the reaction was carried out at -20°C for 60 min. Then, 0.4 mol of PPh2Cl was added, and the reaction was carried out at -78°C for 2 h to obtain a P-containing ionic liquid.

[0041] (4) 0.01 mol of Pd(OAc)2 was dissolved in 50 mL of methanol, and 0.2 mol of P-containing ionic liquid was added under stirring conditions. The mixture was reacted at 90°C for 4 h to obtain a Pd-coordinated P-containing ionic liquid.

[0042] (5) In a 250 mL autoclave, 100 mL of methanol, 0.05 mmol (in terms of molar amount of Pd) of the Pd-coordinated P-containing ionic liquid prepared above, and 5 mmol of methanesulfonic acid were added to the autoclave. After sealing, 0.08 mol of styrene was charged into the autoclave. The autoclave was then replaced with CO for 3 times, and CO was then charged into the autoclave until the pressure of the autoclave reached 4 MPa. The temperature was slowly raised to 100° C. by a temperature controller, and the reaction was carried out for 4 h. The autoclave was cooled to room temperature, and the autoclave was unloaded to obtain methyl phenylpropionate. The liquid obtained by the reaction was quantitatively analyzed by Agilent 6890. The styrene conversion rate was 99%, and the selectivity of the product methyl phenylpropionate was 97%.

[0043] Example 2

[0044] The application of the Pd-coordinated P-containing ionic liquid catalyst in the olefin hydroesterification reaction comprises the following steps:

[0045] (1) 0.2 mol of 1-butylimidazole and 0.2 mol of propane sultone were placed in a 100 mL round-bottom flask and stirred at 90° C. for 2 h to obtain a zwitterionic white solid crude product. The product was filtered and repeatedly washed with ether to remove non-ionic residues. The product was then vacuum dried at 80° C. to obtain a zwitterionic solid powder.

[0046] (2) 0.1 mol of zwitterionic solid powder was transferred into a flask, dissolved with methanol, and 20 mol of NaBF6 was added dropwise. The mixture was reacted at 80°C for 1 h to obtain an ionic liquid.

[0047] (3) Under anhydrous and oxygen-free conditions, 0.2 mol of butyl aluminum was added to 0.2 mol of ionic liquid, and the reaction was carried out at -50°C for 30 min. Then, 0.1 mol of PPh2OCH3 was added, and the reaction was carried out at -45°C for 5 h to obtain a P-containing ionic liquid.

[0048] (4) 0.05 mol of Pd(dba)2 was dissolved in 50 mL of methanol, and 0.2 mol of P-containing ionic liquid was added under stirring conditions. The mixture was reacted at 120°C for 4 h to obtain a Pd-coordinated P-containing ionic liquid.

[0049] (5) In a 250 mL autoclave, 100 mL of methanol, 0.05 mmol (in terms of molar amount of Pd) of the Pd-coordinated P-containing ionic liquid prepared above, and 0.01 mmol of methanesulfonic acid were added to the autoclave, which was sealed and filled with 10 mol of ethylene. The autoclave was then replaced with CO for 3 times, and CO was then filled in until the pressure of the autoclave reached 10 MPa. The temperature was slowly raised to 180° C. by a temperature controller, and the reaction was carried out for 8 h. The autoclave was cooled to room temperature, and the autoclave was unloaded to obtain methyl propionate product. The liquid obtained by the reaction was quantitatively analyzed by Agilent 6890, and the ethylene conversion rate was 98%, and the selectivity of the product methyl propionate was 99%.

[0050] Example 3

[0051] The application of the Pd-coordinated P-containing ionic liquid catalyst in the olefin hydroesterification reaction comprises the following steps:

[0052] (1) 0.5 mol of benzimidazole and 0.5 mol of bromobutyl were placed in a 100 mL round-bottom flask and stirred at 60° C. for 6 h to obtain a zwitterionic white solid crude product. The product was filtered and repeatedly washed with ether to remove non-ionic residues. The product was then vacuum dried at 80° C. to obtain a zwitterionic solid powder.

[0053] (2) 0.1 mol of zwitterionic solid powder was transferred into a flask, dissolved with methanol, and 0.1 mol of CH3SO3H was added dropwise. The mixture was reacted at 30°C for 12 h to obtain an ionic liquid.

[0054] (3) Under anhydrous and oxygen-free conditions, 0.01 mol of metallic lithium was added to 0.5 mol of ionic liquid, and the reaction was carried out at 0°C for 120 min. Then, 0.01 mol of HPPh2 was added, and the reaction was carried out at -25°C for 8 h to obtain a P-containing ionic liquid.

[0055] (4) Dissolve 0.01 mol of PdCl2 in 50 mL of methanol, add 0.2 mol of P-containing ionic liquid under stirring conditions, and react at 80°C for 8 h to obtain Pd-coordinated P-containing ionic liquid.

[0056] (5) In a 250 mL autoclave, 100 mL of methanol, 0.05 mmol (in terms of molar amount of Pd) of the Pd-coordinated P-containing ionic liquid prepared above, and 0.5 mmol of methanesulfonic acid were added to the autoclave, which was sealed and filled with 0.05 mol of ethylene. The autoclave was then replaced with CO for 3 times, and then filled with CO until the pressure of the autoclave reached 1 MPa. The temperature was slowly raised to 50° C. by a temperature controller, and the reaction was carried out for 10 hours. The autoclave was cooled to room temperature, and the autoclave was unloaded to obtain methyl propionate product. The liquid obtained by the reaction was quantitatively analyzed by Agilent 6890, and the ethylene conversion rate was 98%, and the selectivity of the product methyl propionate was 98%.

[0057] Example 4

[0058] The application of the Pd-coordinated P-containing ionic liquid catalyst in the olefin hydroesterification reaction comprises the following steps:

[0059] (1) 0.5 mol of pyridine and 0.5 mol of propane sultone were placed in a 100 mL round-bottom flask and stirred at 80° C. for 10 h to obtain a zwitterionic white solid crude product. The product was filtered and repeatedly washed with ether to remove non-ionic residues. The product was then vacuum dried at 80° C. to obtain a zwitterionic solid powder.

[0060] (2) 0.1 mol of zwitterionic solid powder was transferred into a flask, dissolved with methanol, and 0.5 mol of H2SO4 was added dropwise. The mixture was reacted at 40°C for 10 h to obtain an ionic liquid.

[0061] (3) Under anhydrous and oxygen-free conditions, 0.05 mol of metallic lithium was added to 0.5 mol of ionic liquid, and the reaction was carried out at -30°C for 90 min. Then, 0.1 mol of PPh2Cl was added, and the reaction was carried out at 0°C for 12 h to obtain a P-containing ionic liquid.

[0062] (4) 0.05 mol of Pd(OAc)2 was dissolved in 50 mL of methanol, and 0.2 mol of P-containing ionic liquid was added under stirring conditions. The mixture was reacted at 60°C for 8 h to obtain a Pd-coordinated P-containing ionic liquid.

[0063] (5) In a 250 mL autoclave, 100 mL of methanol, 0.05 mmol (in terms of molar amount of Pd) of the Pd-coordinated P-containing ionic liquid prepared above, and 0.05 mmol of methanesulfonic acid were added to the autoclave, which was sealed and filled with 0.5 mol of ethylene. The autoclave was then replaced with CO for 3 times, and then filled with CO until the pressure of the autoclave reached 6 MPa. The temperature was slowly raised to 110° C. by a temperature controller, and the reaction was carried out for 6 h. The autoclave was cooled to room temperature, and the autoclave was unloaded to obtain methyl propionate product. The liquid obtained by the reaction was quantitatively analyzed by Agilent 6890, and the ethylene conversion rate was 97%, and the selectivity of the product methyl phenylpropionate was 99%.

[0064] Comparative Example 1

[0065] In a 250mL autoclave, 10mg Pd(OAc)2, 2.2g methanesulfonic acid, 0.2g PPh3, and methanol (100mL) were added in sequence. The autoclave was sealed, and the autoclave was replaced with CO for 3 times. Ethylene (0.2mol) was flushed in, and then CO gas was filled in until the pressure of the autoclave reached 3MPa. The temperature was slowly raised to 100°C by a temperature controller, and the reaction was continued for 3h. The reaction was cooled to room temperature, and the autoclave was unloaded. The liquid obtained by the reaction was quantitatively analyzed by Agilent 6890. The ethylene conversion rate was 92%, and the selectivity of the product methyl propionate was 90%.

[0066] Comparative Example 2

[0067] The same as Example 1, except that the reaction temperature after adding the deprotonating agent in step (3) was changed to room temperature, and the other conditions remained unchanged. The ethylene conversion rate was 12%, and the selectivity of the product methyl propionate was 50%.

[0068] Comparative Example 3

[0069] The same as Example 1, except that the cation in step (3) was replaced with ethylenediamine, and the other conditions remained unchanged. The ethylene conversion rate was 0, and the selectivity of the product methyl propionate was 0.

[0070] Comparative Example 4

[0071] The same as Example 1, except that the amount of the deprotonating agent added in step (3) was changed to 0.4 mmol, and the other conditions remained unchanged. The ethylene conversion rate was 30%, and the selectivity of the product methyl propionate was 80%.

[0072] The Pd-coordinated P-containing ionic liquids prepared in the above examples and comparative examples were used to detect the number of Pd active sites on the catalyst using ICP, and the phosphine content on the catalyst using XRF. The test results are shown in Table 1.

[0073] Table 1 Index test results

[0074]

[0075] Of course, the above contents are only preferred embodiments of the present invention and cannot be considered to limit the scope of the embodiments of the present invention. The present invention is not limited to the above examples, and equal changes and improvements made by ordinary technicians in the technical field within the essential scope of the present invention should all fall within the scope of the patent coverage of the present invention.

Claims

1. A method for preparing a Pd-coordinated P-containing ionic liquid catalyst, characterized in that: The following steps are involved: (1) After mixing zwitterion precursor A and zwitterion precursor B, stirring and reacting at 40-90° C. for 2-12 hours to obtain a zwitterion solid crude product, filtering, washing, and drying to obtain a zwitterion solid powder; (2) dissolving the zwitterionic solid powder in methanol, adding an anionic precursor dropwise, and reacting at 30-80° C. for 1-12 h to obtain an ionic liquid; (3) adding a deprotonating agent to the ionic liquid, reacting at -50-0°C for 30-120 min, adding a P-containing precursor, reacting at -78-0°C for 2-12 h, and obtaining a P-containing ionic liquid; (4) dissolving the Pd compound in methanol, adding a P-containing ionic liquid under stirring conditions, and reacting at 40-120° C. for 4-8 hours to obtain a Pd-coordinated P-containing ionic liquid; the molar amount of Pd to the molar amount of P is (1-5):(10-100).

2. The method for preparing the Pd-coordinated P-containing ionic liquid catalyst according to claim 1, characterized in that: In step (1), the zwitterion precursor A is one of 1-methylimidazole, 1-butylimidazole, benzimidazole, and pyridine; the zwitterion precursor B is one of propane sultone, butane sultone, and bromobutane.

3. The method for preparing the Pd-coordinated P-containing ionic liquid catalyst according to claim 1, characterized in that: In step (2), the anion precursor is one of HCl, NaBF6, CH3SO3H, and H2SO4.

4. The method for preparing the Pd-coordinated P-containing ionic liquid catalyst according to claim 1, characterized in that: In step (2), the molar ratio of the zwitterionic solid powder to the anionic precursor is (1-5):(1-100).

5. The method for preparing the Pd-coordinated P-containing ionic liquid catalyst according to claim 1, characterized in that: In step (3), the deprotonating agent is one of n-butyl lithium, butyl aluminum, and metallic lithium; and the P-containing precursor is one of PPh2Cl, PPh2OCH3, and HPPh2.

6. The method for preparing the Pd-coordinated P-containing ionic liquid catalyst according to claim 1, characterized in that: In step (3), the molar ratio of the ionic liquid to the deprotonating agent is (1-5):(0.1-1); the molar ratio of the ionic liquid to the P-containing precursor is (1-5):(0.1-2).

7. The method for preparing the Pd-coordinated P-containing ionic liquid catalyst according to claim 1, characterized in that: The Pd compound in step (4) is one of Pd(OAc)2, PdCl2, and Pd(dba)2.

8. A Pd-coordinated P-containing ionic liquid catalyst, characterized in that: It is prepared by the preparation method described in any one of claims 1 to 7.

9. Use of the Pd-coordinated P-containing ionic liquid catalyst according to claim 8 in olefin hydroesterification reaction, characterized in that: The alcohol, Pd-coordinated P-containing ionic liquid catalyst and acid auxiliary agent are mixed, the terminal olefin is charged, the pressure is increased, the temperature is increased, and the reaction is carried out.

10. Use of the Pd-coordinated P-containing ionic liquid catalyst according to claim 9 in olefin hydroesterification reaction, characterized in that: The molar ratio of H in the acid auxiliary agent to Pd in ​​the Pd-coordinated P-containing ionic liquid catalyst is (1-50): (0.5-5), the single-pot addition amount of terminal olefin is 0.05mol-10mol, the pressure is increased to 1-10Mpa, the temperature is increased to 50-180°C, and the reaction is carried out for 2-10h.

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