PAF supported ruthenium catalyst as well as preparation method and application thereof

Abstract

The invention provides a PAF supported ruthenium catalyst as well as a preparation method and application thereof, and relates to the technical field of heterogeneous catalyst preparation. The catalyst comprises a PAF material containing a CNN ligand and a ruthenium active center, the CNN ligand has a tridentate chelating structure formed by N-heterocyclic carbene and bipyridine, coordination sites can be provided for ruthenium atoms, and meanwhile, dissociation of the ruthenium atoms and the ligand is hindered by stable metal chelating, so that the stability and catalytic performance of the catalyst are improved. The catalyst provided by the invention can catalyze ester hydrogenation reduction and polyester hydrogenation depolymerization under mild conditions, is easy to separate from reaction products, and has good recycling performance.

Description

Technical Field

[0001] The present invention relates to the technical field of heterogeneous catalyst preparation, and in particular to a PAF-supported ruthenium catalyst and a preparation method and application thereof. Background Art

[0002] Polyester is one of the main types of plastics. With the rapid increase in the production and sales of polyester materials, more and more waste polyester materials are generated. Therefore, the recycling of waste polyester materials has received increasing attention in recent years. At present, the waste polyester materials are mainly depolymerized under the action of heat and chemical reagents to generate corresponding monomers or oligomers. After separation and purification, the products can be reused as monomers for the production of polyester materials or raw materials for the synthesis of other chemical products, thereby realizing the recycling of resources.

[0003] In the field of ester reduction and polyester degradation, a series of pincer transition metal complexes can catalyze the hydrogenation of esters or polyesters to prepare the corresponding alcohol monomers. Compared with other processes, this method does not produce by-products and has obvious advantages in both the environment and the economy. Ruthenium metal catalysts with pincer ligand structures have been reported as follows: In 2005, Milstein et al. reported that a type of PNN-type pincer ruthenium catalyst with a pyridine skeleton was applied to the hydrogenation reduction of aromatic esters and fatty esters, and obtained good hydrogenation results under low hydrogen pressure; in 2011, Takasago Co., Ltd. first reported the use of a tridentate PNP-type pincer ligand ruthenium catalyst Ru-MACHO connected with diethylamine to achieve the hydrogenation of fatty acid esters under mild conditions and applied it to the synthesis of (R)-1,2-propylene glycol and L-menthaneoxyethanol; in 201 In 2013, Gusev developed an air-stable SNS-type pincer-type ruthenium complex catalyst based on the work of his predecessors. It showed excellent efficiency in the hydrogenation of a wide range of substrates (esters, ketones, imines) with C=X bonds and in the receptor-free dehydrogenation coupling of ethanol and ethyl acetate. In 2014, Leitner et al. found that the ruthenium catalyst with a tridentate Triphos ligand showed high catalytic activity for functionalized esters such as γ-valerolactone, methyl itaconate, and lactide. The catalyst can directly hydrogenate carboxylic acids to prepare the corresponding alcohols, but requires a relatively high reaction temperature.

[0004] Although the homogeneous catalytic system commonly used in the prior art has excellent catalytic activity for the hydrogenation reduction of esters and polyesters, the homogeneous catalyst will remain in the reaction system, resulting in difficulty in separating the catalyst from the product and difficulty in reusing the catalyst. Therefore, it is urgent to provide a solution to improve the above problems. Summary of the invention

[0005] The present invention aims to provide a PAF-loaded ruthenium catalyst and a preparation method and application thereof. The catalyst can catalyze ester hydrogenation reduction and polyester hydrogenation depolymerization under mild conditions, is easy to separate from the reaction product, and has good recycling performance.

[0006] In the first aspect, the present invention provides a PAF-supported ruthenium catalyst having the general formula as shown in Formula I:

[0007]

[0008] Wherein, X1 and X2 are independently any one of H, Cl, Br, I, CN and R, preferably any one of H, Cl, Br and CN;

[0009] X3 is any one of CO, PR3 and NR3, preferably CO or PPh3;

[0010] R1 is C1~C 10 Alkyl, C3~C 20 Cycloalkyl, phenyl and C6~C 20 Any one of the substituted phenyl groups, preferably any one of methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclohexyl, phenyl, p-methylphenyl, 2,6-dimethylphenyl and mesitylene;

[0011] n1, n2, n3, n4, n5 and n6 are independently any integer from 0 to 30, preferably any integer from 8 to 20.

[0012] In a second aspect, the present invention provides a method for preparing a PAF-supported ruthenium catalyst, comprising the following steps:

[0013] S1. In N,N-dimethylformamide solvent, under the catalysis of tetrakis(triphenylphosphine)palladium and potassium carbonate, the CNN ligand shown in formula II, bromoaryl hydrocarbon and arylboron compound are mixed and reacted to prepare PAF material;

[0014]

[0015] Wherein X4 is any one of Cl and Br;

[0016] S2. In an organic solvent, a PAF material, a base and a ruthenium precursor are mixed and reacted to obtain a PAF-supported ruthenium catalyst.

[0017] The present invention uses PAF material as an active carrier of the catalyst, which can increase the catalytic contact area, thereby enhancing the catalytic performance, and can effectively limit the movement of the active center, making it difficult for it to be lost or aggregated into clusters. At the same time, it can also make the overall catalytic reaction into a heterogeneous reaction, which is easy to separate and recover after the reaction, so that the catalyst can be recycled.

[0018] Optionally, the reactions of step S1 and step S2 are both carried out in an inert gas atmosphere, specifically, including at least one of a nitrogen atmosphere and an argon atmosphere.

[0019] Optionally, in step S1, the brominated aromatic hydrocarbon includes at least one of p-dibromobenzene, mesitylene-tribromobenzene, 1,3,5-tris(4-bromophenyl)benzene, 4,4-dibromobiphenyl and 4,4″-dibromoterphenyl.

[0020] Optionally, in step S1, the aromatic boron compound includes at least one of 1,4-phenyldiboronic acid, 1,4-phenyldiboronic acid dipinacol ester, 4,4'-biphenyldiboronic acid, 4,4'-biphenyldiboronic acid dipinacol ester, 1,3,5-phenyltriboric acid tripinacol ester, 1,3,5-tris(4-phenylboronic acid)benzene and 1,3,5-tris(4-phenylboronic acid pinacol ester)benzene.

[0021] Optionally, in step S1, the molar ratio of the bromine element in the CNN ligand, the bromine element in the brominated aromatic hydrocarbon, and the boron element in the aromatic boron compound is 1:(5-95):(6-96), preferably 1:(29-65):(30-66).

[0022] The CNN-type ligand has a tridentate chelate structure formed by nitrogen heterocyclic carbene and bipyridine, which can provide a protected environment for the ruthenium metal atom, and the two stable metal chelate rings hinder the dissociation of the ruthenium metal atom and the ligand, thereby improving the stability and catalytic performance of the catalyst.

[0023] Optionally, in step S2, the organic solvent includes at least one of benzene, toluene, o-xylene, m-xylene, p-xylene, mesitylene, n-pentane, n-hexane, heptane, octane, 1,4-dioxane and tetrahydrofuran.

[0024] Optionally, in step S2, the base includes any one of lithium hexamethyldisilazide, sodium hexamethyldisilazide, potassium hexamethyldisilazide, potassium tert-butoxide and sodium tert-butoxide.

[0025] Optionally, in step S2, the ruthenium precursor includes any one of tris(triphenylphosphine)ruthenium(II)chlorocarbonyl, bis(phenylruthenium dichloride), dichloro(pod)ruthenium(II) dimer, isopropylphenylruthenium dichloride, dichloro(p-methylisopropylbenzene)ruthenium(II) dimer, cyclooctadieneruthenium dichloride, tricarbonyldichlororuthenium dimer, hexaammineruthenium(II) chloride, diiodo(p-cymene)ruthenium(II) dimer, bis(ethylcyclopentadiene)ruthenium(II) and dichlorotetrakis(triphenylphosphine)ruthenium.

[0026] Optionally, in step S2, the molar ratio of the CNN ligand in the PAF material, the base and the ruthenium element in the ruthenium precursor is (0.5-2):(0.5-2):1, preferably (1-1.5):(1-1.5):1.

[0027] Optionally, step S2 includes: reacting the PAF material with a base at -78°C for 10 to 30 minutes in advance, then slowly heating the temperature to -30°C for reaction for 2 to 5 hours, and then adding a ruthenium precursor for reaction at 80 to 120°C for 12 to 36 hours.

[0028] In fact, the reaction of the PAF material and the ruthenium precursor under a heating environment can promote the loading of the CNN ligand-containing PAF material on the ruthenium precursor and improve the loading uniformity.

[0029] In a third aspect, the present invention provides an application of the above-mentioned PAF-supported ruthenium catalyst in a catalytic hydrogenation reaction of an ester or a hydrogenation degradation reaction of a polyester, comprising:

[0030] Under the conditions of 60-200° C., 0.5-6 MPa of hydrogen atmosphere, in an alkaline solvent environment, under the action of a catalyst, the ester undergoes a catalytic hydrogenation reaction or the polyester undergoes a hydrogenation degradation reaction.

[0031] Optionally, the alkaline solute in the alkaline solvent environment includes any one of sodium tert-butoxide, potassium tert-butoxide, sodium methoxide and sodium ethoxide.

[0032] Optionally, the solvent in the alkaline solvent environment includes at least one of benzene, toluene, p-xylene, anisole, tetrahydrofuran and 1,4-dioxane.

[0033] Optionally, the ester includes any one of methyl benzoate, ethyl benzoate, benzyl benzoate, valerolactone, caprolactone, ethylene dibenzoate, diethylene dibenzoate, triethylene dibenzoate, propylene dibenzoate, dimethyl terephthalate, diethyl terephthalate, diethyl phthalate, diethyl isophthalate and dibutyl terephthalate.

[0034] Optionally, the polyester includes any one of polycaprolactone, polybutylene succinate, polyethylene terephthalate and polybutylene terephthalate.

[0035] Optionally, the reaction time is 1 to 72 hours. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly introduce the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments.

[0037] Figure 1 The structural formula of the PAF-supported ruthenium catalyst provided by the present invention;

[0038] Figure 2 This is the hydrogen nuclear magnetic resonance spectrum of the product obtained in Example 1 of the present invention;

[0039] Figure 3This is the hydrogen nuclear magnetic resonance spectrum of the product obtained in Example 2 of the present invention. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be the common meanings understood by people with general skills in the field to which the present invention belongs.

[0041] The present invention provides a PAF-supported ruthenium catalyst having a general formula as shown in Formula I:

[0042]

[0043] Wherein, X1 and X2 are independently any one of H, Cl, Br, I, CN and R, preferably any one of H, Cl, Br and CN;

[0044] X3 is any one of CO, PR3 and NR3, preferably CO or PPh3;

[0045] R1 is C1~C 10 Alkyl, C3~C 20 Cycloalkyl, phenyl and C6~C 20 Any one of the substituted phenyl groups, preferably any one of methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclohexyl, phenyl, p-methylphenyl, 2,6-dimethylphenyl and mesitylene;

[0046] n1, n2, n3, n4, n5 and n6 are independently any integer from 0 to 30, preferably any integer from 8 to 20.

[0047] The present invention also provides a method for preparing a PAF-supported ruthenium catalyst, comprising the following steps:

[0048] S1. In N,N-dimethylformamide solvent, under the catalysis of tetrakis(triphenylphosphine)palladium and potassium carbonate, the CNN ligand shown in formula II, bromoaryl hydrocarbon and arylboron compound are mixed and reacted to prepare PAF material;

[0049]

[0050] Wherein X4 is any one of Cl and Br;

[0051] S2. In an organic solvent, a PAF material, a base and a ruthenium precursor are mixed and reacted to obtain a PAF-supported ruthenium catalyst.

[0052] In some embodiments, the reactions of step S1 and step S2 are both performed in an inert gas atmosphere, specifically, including at least one of a nitrogen atmosphere and an argon atmosphere.

[0053] In some embodiments, when performing step S1, the brominated aromatic hydrocarbon includes at least one of p-dibromobenzene, mesitylene-tribromobenzene, 1,3,5-tris(4-bromophenyl)benzene, 4,4-dibromobiphenyl and 4,4″-dibromoterphenyl.

[0054] In some embodiments, when performing step S1, the aromatic boron compound includes at least one of 1,4-phenyldiboronic acid, 1,4-phenyldiboronic acid dipinacol ester, 4,4'-biphenyldiboronic acid, 4,4'-biphenyldiboronic acid dipinacol ester, 1,3,5-benzenetriboric acid tripinacol ester, 1,3,5-tris(4-phenylboronic acid)benzene and 1,3,5-tris(4-phenylboronic acid pinacol ester)benzene.

[0055] In some embodiments, when performing step S1, the molar ratio of the bromine element in the CNN ligand, the bromine element in the brominated aromatic hydrocarbon, and the boron element in the aromatic boron compound is 1:(5-95):(6-96), preferably 1:(29-65):(30-66).

[0056] In some embodiments, when performing step S2, the organic solvent includes at least one of benzene, toluene, o-xylene, m-xylene, p-xylene, mesitylene, n-pentane, n-hexane, heptane, octane, 1,4-dioxane and tetrahydrofuran.

[0057] In some embodiments, when performing step S2, the base includes any one of lithium hexamethyldisilazide, sodium hexamethyldisilazide, potassium hexamethyldisilazide, potassium tert-butoxide and sodium tert-butoxide.

[0058] In some embodiments, when performing step S2, the ruthenium precursor includes any one of tris(triphenylphosphine)ruthenium(II)chlorocarbonyl, bis(phenylruthenium dichloride), dichloro(pod)ruthenium(II) dimer, isopropylphenylruthenium dichloride, dichloro(p-methylisopropylbenzene)ruthenium(II) dimer, cyclooctadieneruthenium dichloride, tricarbonyldichlororuthenium dimer, hexaammineruthenium(II) chloride, diiodo(p-cymene)ruthenium(II) dimer, bis(ethylcyclopentadiene)ruthenium(II) and dichlorotetrakis(triphenylphosphine)ruthenium.

[0059] In some embodiments, when executing step S2, the molar ratio of the CNN ligand in the PAF material, the base and the ruthenium element in the ruthenium precursor is (0.5-2):(0.5-2):1, preferably (1-1.5):(1-1.5):1.

[0060] In fact, when executing step S2, the following sub-steps are included:

[0061] S2.1, in an organic solvent, react the PAF material with a base at -78°C for 10-30 minutes, then slowly heat the temperature to -30°C and react for 2-5 hours to obtain an intermediate;

[0062] S2.2. Add a ruthenium precursor to the intermediate and react at 80-120° C. for 12-36 hours to obtain a product. Cool, filter, wash and dry the product to obtain a PAF-loaded ruthenium catalyst.

[0063] The present invention also provides an application of the PAF-supported ruthenium catalyst in a catalytic hydrogenation reaction of an ester or a hydrogenation degradation reaction of a polyester, comprising:

[0064] Under the conditions of 60-200° C., 0.5-6 MPa of hydrogen atmosphere, in an alkaline solvent environment, under the action of a catalyst, the ester undergoes a catalytic hydrogenation reaction or the polyester undergoes a hydrogenation degradation reaction.

[0065] In some embodiments, the alkaline solute in the alkaline solvent environment includes any one of sodium tert-butoxide, potassium tert-butoxide, sodium methoxide, and sodium ethoxide.

[0066] In some embodiments, the solvent in the alkaline solvent environment includes at least one of benzene, toluene, p-xylene, anisole, tetrahydrofuran and 1,4-dioxane.

[0067] In some embodiments, the ester includes any one of methyl benzoate, ethyl benzoate, benzyl benzoate, valerolactone, caprolactone, ethylene dibenzoate, diethylene dibenzoate, triethylene dibenzoate, propylene dibenzoate, dimethyl terephthalate, diethyl terephthalate, diethyl phthalate, diethyl isophthalate and dibutyl terephthalate.

[0068] In some embodiments, the polyester includes any one of polycaprolactone, polybutylene succinate, polyethylene terephthalate, and polybutylene terephthalate.

[0069] In some embodiments, the reaction time is 1 to 72 hours.

[0070] Preparation Example 1

[0071] Preparation Example 1 of the present invention provides a method for preparing a PAF-supported ruthenium catalyst, comprising the following steps:

[0072] S1. Under nitrogen atmosphere, 0.05mmol CNN ligand, 1.45mmol p-dibromobenzene, 1.2mmol 1,4-phenylenediboronic acid, 0.2mmol 1,3,5-phenyltriboric acid tripinacol ester and 20mL N,N-dimethylformamide were mixed, and 2.5mL 2mol / L potassium carbonate solution and 0.06mmol tetrakis(triphenylphosphine)palladium were added to obtain a mixture, and the mixture was degassed by 3 freeze-thaw cycles, and heated at 150°C for 36h, then cooled to room temperature, separated by suction filtration, washed with dichloromethane, tetrahydrofuran and water respectively, and then transferred to a 120°C vacuum drying oven and dried to constant weight to obtain a PAF material;

[0073] S2.1. In a nitrogen atmosphere, the PAF material was mixed with toluene, and 0.05 mmol potassium hexamethyldisilazide was added at -78°C for 15 min, and the temperature was slowly raised to -30°C for 3 h to obtain an intermediate;

[0074] S2.2. Under a nitrogen atmosphere, add 0.05 mmol carbonylchlorohydrotris(triphenylphosphine)ruthenium (II) to the intermediate for mixed dispersion. After stirring and reacting in an oil bath at 100°C for 16 hours, cool to room temperature, separate by suction filtration, wash with toluene, transfer to a vacuum drying oven at 120°C and dry to constant weight to obtain a PAF-loaded ruthenium catalyst.

[0075] Preparation Example 2

[0076] Preparation Example 2 of the present invention provides a method for preparing a PAF-supported ruthenium catalyst, which is different from Preparation Example 1 in that:

[0077] In step S1, the input amount of p-dibromobenzene is 2.35 mmol, the input amount of 1,4-phenylenediboronic acid is 2.1 mmol, the input amount of N,N-dimethylformamide is 40 mL, the input amount of potassium carbonate solution is 3.9 mL, and the input amount of tetrakis(triphenylphosphine)palladium is 0.11 mmol;

[0078] In step S2.1, the reaction time of the PAF material and potassium hexamethyldisilazide is 20 minutes, and the reaction time at -30°C is 4 hours;

[0079] The reaction time in step S2.2 in an oil bath at 100° C. is 24 h.

[0080] Preparation Example 3

[0081] Preparation Example 3 of the present invention provides a method for preparing a PAF-supported ruthenium catalyst, which is different from Preparation Example 1 in that:

[0082] In step S1, the input amount of p-dibromobenzene is 3.25 mmol, the input amount of 1,4-phenylenediboronic acid is 3.0 mmol, the input amount of N,N-dimethylformamide is 60 mL, the input amount of potassium carbonate solution is 5.5 mL, and the input amount of tetrakis(triphenylphosphine)palladium is 0.15 mmol;

[0083] In step S2.1, the reaction time of the PAF material and potassium hexamethyldisilazide is 25 minutes, and the reaction time at -30°C is 5 hours;

[0084] The reaction time in step S2.2 in an oil bath at 100° C. is 30 h.

[0085] Example 1

[0086] The PAF-supported ruthenium catalyst prepared in Preparation Example 1 is applied to catalyze the hydrogenation reaction of esters, comprising the following steps:

[0087] Y1. Under a nitrogen atmosphere, in an alkaline solvent environment containing 11.2 mg of potassium tert-butoxide and 1 mL of toluene, 44.0 mg of PAF-supported ruthenium catalyst and 150.2 mg of ethyl benzoate were added to a 25 mL autoclave, and the gas in the autoclave was replaced with hydrogen three times, and the hydrogen pressure in the autoclave was adjusted to 4 MPa to obtain a reaction mixture system;

[0088] Y2. After stirring the reaction mixture at 135° C. in a hydrogen atmosphere for 6 h, the autoclave was cooled to room temperature, the PAF-supported ruthenium catalyst was recovered by filtration, and the nuclear magnetic yield of the product in the reaction solution was measured to be 98.0%.

[0089] The obtained product was characterized by H NMR spectroscopy. Figure 2 As shown, it is explained that under the catalytic action of the PAF-supported ruthenium catalyst prepared in Preparation Example 1, benzyl alcohol and ethanol were prepared from ethyl benzoate.

[0090] Example 2

[0091] The PAF-supported ruthenium catalyst prepared in Preparation Example 1 was used to catalyze the hydrogenation degradation reaction of polyester, which was different from Example 1 in that:

[0092] The reaction substrate added in step Y1 is 114 mg of polycaprolactone;

[0093] The stirring reaction time of the mixed system in step Y2 is 12 hours.

[0094] The NMR yield of the product in the reaction solution was measured to be 94.8%. The obtained product was characterized by hydrogen NMR spectrum. Figure 3 As shown, it is explained that under the catalytic action of the PAF-loaded ruthenium catalyst prepared in Preparation Example 1, hexanediol was prepared from polycaprolactone.

[0095] Example 3 to Example 20

[0096] Examples 3 to 20 provide the use of the PAF-supported ruthenium catalyst prepared in Preparation Examples 1 to 3 in the catalytic hydrogenation reaction of esters, respectively. The difference from Example 1 is the source of the catalyst, the type of reaction substrate, the type of solvent, the hydrogen pressure, the reaction temperature and the reaction time, as shown in Table 1:

[0097] Table 1 Differences between Examples 3 to 20 and Example 1

[0098]

[0099]

[0100] Example 21 to Example 30

[0101] Examples 21 to 30 respectively provide an application of a PAF-supported ruthenium catalyst prepared in Preparation Examples 1 to 3 in catalyzing the hydrogenation degradation reaction of polyester, which is different from Example 2 in the source of the catalyst, the type of reaction substrate, the type of solvent, the hydrogen pressure, the reaction temperature and the reaction time, as shown in Table 2:

[0102] Table 2 Differences between Examples 21 to 30 and Example 2

[0103]

[0104] Although the embodiments of the present invention are described in detail above, it is obvious to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention as described in the claims. Moreover, the present invention described herein may have other embodiments and may be implemented or realized in a variety of ways.

Claims

1. A PAF-supported ruthenium catalyst having the general formula as shown in Formula I: in, X1 and X2 are independently any one of H, Cl, Br, I, CN and R, and X3 is any one of CO, PR3 and NR3; R1 is C1~C 10 Alkyl, C3~C 20 Cycloalkyl, phenyl and C6~C 20 Any one of the substituted phenyl groups; n1, n2, n3, n4, n5 and n6 are independently any integer from 0 to 30.

2. A method for preparing a PAF-supported ruthenium catalyst, characterized in that: The following steps are involved: S1. In N,N-dimethylformamide solvent, under the catalysis of tetrakis(triphenylphosphine)palladium and potassium carbonate, the CNN ligand shown in formula II, bromoaryl hydrocarbon and arylboron compound are mixed and reacted to prepare PAF material; Wherein, X4 is any one of Cl and Br; S2. In an organic solvent, a PAF material, a base and a ruthenium precursor are mixed and reacted to obtain a PAF-loaded ruthenium catalyst.

3. The preparation method according to claim 2, characterized in that: The reactions in step S1 and step S2 are both carried out in an inert gas atmosphere; the inert gas atmosphere includes at least one of a nitrogen atmosphere and an argon atmosphere.

4. The preparation method according to claim 2, characterized in that: In step S1: the brominated aromatic hydrocarbon includes at least one of p-dibromobenzene, mesitylene-tribromobenzene, 1,3,5-tris(4-bromophenyl)benzene, 4,4-dibromobiphenyl and 4,4"-dibromoterphenyl; The aromatic boron compound comprises at least one of 1,4-phenyldiboronic acid, 1,4-phenyldiboronic acid dipinacol ester, 4,4'-biphenyldiboronic acid, 4,4'-biphenyldiboronic acid dipinacol ester, 1,3,5-phenyltriboric acid tripinacol ester, 1,3,5-tris(4-phenylboronic acid)benzene and 1,3,5-tris(4-phenylboronic acid pinacol ester)benzene; The molar ratio of the bromine element in the CNN ligand, the bromine element in the bromoaryl hydrocarbon and the boron element in the arylboron compound is 1:(5-95):(6-96).

5. The preparation method according to claim 2, characterized in that: In step S2: the organic solvent includes at least one of benzene, toluene, o-xylene, m-xylene, p-xylene, mesitylene, n-pentane, n-hexane, heptane, octane, 1,4-dioxane and tetrahydrofuran; The base includes any one of lithium hexamethyldisilazide, sodium hexamethyldisilazide, potassium hexamethyldisilazide, potassium tert-butoxide and sodium tert-butoxide; The ruthenium precursor includes any one of tris(triphenylphosphine)ruthenium(II)chlorocarbonyl, bis(phenylruthenium dichloride), dichloro(pod)ruthenium(II) dimer, isopropylphenylruthenium dichloride, dichloro(p-methylisopropylbenzene)ruthenium(II) dimer, cyclooctadieneruthenium dichloride, tricarbonyldichlororuthenium dimer, hexaammineruthenium(II) chloride, diiodo(p-cymene)ruthenium(II) dimer, bis(ethylcyclopentadiene)ruthenium(II) and dichlorotetrakis(triphenylphosphine)ruthenium; The molar ratio of the CNN ligand in the PAF material, the base and the ruthenium element in the ruthenium precursor is (0.5-2):(0.5-2):

1.

6. The preparation method according to claim 2, characterized in that: Step S2 includes: reacting the PAF material with a base at -78°C for 10 to 30 minutes in advance, then slowly heating the temperature to -30°C for 2 to 5 hours, and then adding a ruthenium precursor for reaction at 80 to 120°C for 12 to 36 hours.

7. Use of the PAF-supported ruthenium catalyst as claimed in claim 1 or the PAF-supported ruthenium catalyst prepared by the preparation method according to any one of claims 2 to 6 in catalytic hydrogenation reaction of ester or hydrogenation degradation reaction of polyester.

8. The use according to claim 7, characterized in that: Under the conditions of 60-200° C., 0.5-6 MPa of hydrogen atmosphere, in an alkaline solvent environment, under the action of a catalyst, the ester undergoes a catalytic hydrogenation reaction or the polyester undergoes a hydrogenation degradation reaction.

9. The use according to claim 8, characterized in that: The alkaline solute in the alkaline solvent environment includes any one of sodium tert-butoxide, potassium tert-butoxide, sodium methoxide and sodium ethoxide; The solvent in the alkaline solvent environment includes at least one of benzene, toluene, p-xylene, anisole, tetrahydrofuran and 1,4-dioxane; The esters include any one of methyl benzoate, ethyl benzoate, benzyl benzoate, valerolactone, caprolactone, ethylene dibenzoate, diethylene dibenzoate, triethylene dibenzoate, propylene dibenzoate, dimethyl terephthalate, diethyl terephthalate, diethyl phthalate, diethyl isophthalate and dibutyl terephthalate; The polyester includes any one of polycaprolactone, polybutylene succinate, polyethylene terephthalate and polybutylene terephthalate.

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