Bidentate phosphine ligand, carbonylation reaction catalyst, preparation methods and applications of bidentate phosphine ligand and carbonylation reaction catalyst, and 1, 3-butadiene carbonylation reaction

Abstract

The invention relates to the field of carbonylation reaction catalysts, and discloses a bidentate phosphine ligand and a preparation method thereof, a carbonylation reaction catalyst and a preparation method and application thereof, and a 1, 3-butadiene carbonylation reaction. The general formula of the bidentate phosphine ligand is A-Z1-S-Z2-Si (OR1) n (R2) 3-n, wherein the general formula of A is # imgabs0 #; Z1 and Z2 are respectively and independently alkylene; r1 and R2 are each independently an alkyl group; n is a positive integer from 1 to 3. The supported catalyst prepared from the bidentate phosphine ligand has the advantages of easiness in recovery, reusability, high catalytic efficiency, mild reaction conditions and the like. And the catalyst has high conversion rate and high selectivity in the carbonylation reaction of 1, 3-butadiene.

Description

Technical Field

[0001] The present invention relates to the field of carbonylation reaction catalysts, and in particular to a bidentate phosphine ligand, a supported catalyst containing the bidentate phosphine ligand, a method for preparing the supported catalyst, application of the supported catalyst in carbonylation reaction, and a method for synthesizing adipic acid diester compounds by carbonylation of 1,3-butadiene. Background Art

[0002] In the contemporary chemical industry, homogeneous palladium is often used as a carbonylation catalyst to prepare various carboxylic acids and their derivatives. However, the use of homogeneous palladium catalysts to catalyze carbonylation reactions often leads to serious disadvantages such as high cost, difficulty in separation, and non-recyclability of palladium catalysts, which largely limits their application in large-scale synthesis or industry.

[0003] Mesoporous silica material is an ideal carrier for catalysts, with high specific surface area, high thermal stability, large pore volume and pore homogeneity. Combining mesoporous silica material with the above homogeneous palladium catalyst and chemically immobilizing homogeneous palladium on a silicon carrier to obtain a supported catalyst can effectively overcome the defects of high cost and difficult separation of homogeneous palladium catalysts, and can also simply achieve the recycling and reuse of palladium catalysts by filtering, washing, drying and other means.

[0004] As a common carbonylation reaction product, adipic acid diester compounds are widely used in the production of plasticizers, perfumes, lubricants, solvents, active pharmaceutical ingredients (API) and important polyamides (nylon).

[0005] In industrial production, 1,3-butadiene is generally used as a reactant to produce adipic acid diester compounds through dihydroesterification, which is a low-cost, high-efficiency, and green environmentally friendly route. However, in order to achieve high selectivity and cost-effective synthesis of adipic acid diester compounds, a carbonylation reaction catalyst with good catalytic performance and high recovery rate is also required. Summary of the invention

[0006] The purpose of the present invention is to overcome the problems existing in the existing carbonylation reaction, such as high reaction cost, difficulty in product separation, and non-recyclable palladium catalyst, and provide a bidentate phosphine ligand, a supported catalyst containing the bidentate phosphine ligand, a method for preparing the supported catalyst, the application of the supported catalyst in the carbonylation reaction, and a method for synthesizing adipic acid diester compounds by carbonylation of 1,3-butadiene. Among them, the catalyst of the present invention has the advantages of easy recovery, reusability, high catalytic efficiency, and mild reaction conditions compared with other catalysts of the same type. And the catalyst has high conversion rate and high selectivity in the carbonylation reaction of 1,3-butadiene.

[0007] In order to achieve the above object, the present invention provides a bidentate phosphine ligand in a first aspect, wherein the bidentate phosphine ligand has a general formula of AZ 1 -SZ 2 -Si(OR 1 ) n (R 2 ) 3-n ;

[0008] Among them, the general formula of A is R 3 , R 4 , R 5 , R 6 are the same as or different from each other and are each independently selected from C1-C10 straight or branched alkyl, C1-C10 alkoxy, C3-C10 cycloalkyl, C2-C10 heterocycloalkyl, substituted or unsubstituted C6-C20 aryl, C6-C20 aryloxy or C6-C20 heteroaryl; Z 1 and Z 2 Each is independently an alkylene group; R 1 and R 2 Each is independently an alkyl group; n is a positive integer of 1-3.

[0009] The second aspect of the present invention provides a supported catalyst, wherein the catalyst comprises the bidentate phosphine ligand described in the first aspect, palladium and a silicon-based mesoporous molecular sieve.

[0010] The third aspect of the present invention provides a method for preparing the supported catalyst according to the second aspect, the method comprising:

[0011] (1) heating the silicon-based mesoporous molecular sieve to remove water and activate it to obtain a carrier;

[0012] (2) mixing the carrier obtained in step (1) with a bidentate phosphine ligand in the presence of a solvent, and then drying to obtain a first solid;

[0013] (3) In the presence of an organic solvent, the first solid obtained in step (2) is mixed with a palladium salt and dried to obtain the catalyst.

[0014] The fourth aspect of the present invention provides an application of the supported catalyst of the second aspect in a carbonylation reaction; preferably, the application in the carbonylation of 1,3-butadiene to synthesize adipic acid diester compounds.

[0015] A fifth aspect of the present invention provides a method for synthesizing adipic acid diester compounds by carbonylation of 1,3-butadiene, the method comprising:

[0016] In the presence of CO, a supported catalyst, a catalyst promoter, an alcohol and a solution of 1,3-butadiene are contacted to carry out a carbonylation reaction; wherein the supported catalyst is the supported catalyst described in the second aspect.

[0017] The present invention creatively proposes a novel bidentate phosphine ligand structure containing Si atoms. In addition to Si atoms, the bidentate phosphine ligand also contains R 1 , R 2 , R 3 , R 4 , R 5 , R 6 The supported catalyst prepared by using the bidentate phosphine ligand has higher catalytic efficiency and better stability, and can maintain a high catalytic efficiency after multiple catalytic reactions.

[0018] Through the above technical solution, the present invention has the following advantages:

[0019] (1) The bidentate phosphine ligand can be more efficiently and firmly grafted onto the silica-based mesoporous molecular sieve carrier, with a higher ligand loading capacity;

[0020] (2) The supported catalyst is easy to recover and reuse;

[0021] (3) Supported catalysts have high catalytic efficiency, good selectivity, and mild reaction conditions;

[0022] (4) The supported catalyst has high conversion rate and high selectivity in the carbonylation reaction of 1,3-butadiene. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a TEM image of the catalyst prepared in Example 1. DETAILED DESCRIPTION

[0024] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0025] The first aspect of the present invention provides a bidentate phosphine ligand, wherein the general formula of the bidentate phosphine ligand is AZ 1 -SZ 2 -Si(OR 1 ) n (R 2 ) 3-n ;

[0026] Among them, the general formula of A is R 3 , R 4 , R 5 , R 6 are the same as or different from each other and are each independently selected from C1-C10 straight or branched alkyl, C1-C10 alkoxy, C3-C10 cycloalkyl, C2-C10 heterocycloalkyl, substituted or unsubstituted C6-C20 aryl, C6-C20 aryloxy or C6-C20 heteroaryl; Z 1 and Z 2 Each is independently an alkylene group; R 1 and R 2 Each is independently an alkyl group; n is a positive integer of 1-3.

[0027] According to a preferred embodiment of the present invention, Z 1 For -(CH 2 ) a -, a is a positive integer ranging from 3 to 11. For example, it can be 3, 4, 5, 6, 7, 8, 9, 10, 11, etc.

[0028] According to a preferred embodiment of the present invention, Z 2 For -(CH 2 ) b -, b is a positive integer ranging from 1 to 3. For example, it can be 1, 2, 3, etc.

[0029] The inventors of the present invention have found that the bidentate phosphine ligand can be used to prepare a supported catalyst.

[0030] According to a preferred embodiment of the present invention, R 3 , R 4 , R 5 , R 6 R is each independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, n-hexyl, n-heptyl, n-octyl, isooctyl, n-nonyl, adamantyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, phenyl, fluorophenyl, bromophenyl, chlorophenyl, o-tolyl, p-tolyl, m-tolyl, o-ethylphenyl, p-ethylphenyl, m-ethylphenyl, o-isopropylphenyl, p-isopropylphenyl, m-isopropylphenyl, methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, nonyloxy, decyloxy, 2-pyridyl, phenoxy, methylphenoxy, ethylphenoxy, n-propylphenoxy, isopropylphenoxy, 2-thienyl; more preferably, R 3 , R 4 , R 5 , R 6Each is independently selected from n-butyl, isobutyl, sec-butyl, tert-butyl, adamantyl, cyclobutane, cyclopentane, cyclohexane, cycloheptane, fluorophenyl, bromophenyl, phenyl, propoxy, butoxy, pentyloxy, 2-pyridyl, phenoxy, n-propylphenoxy or 2-thienyl. 3 , R 4 , R 5 , R 6 The bidentate phosphine ligand of the group can enable the subsequently prepared supported catalyst to better promote the rapid isomerization of 1,3-butadiene, thereby further improving the activity of the palladium catalyst, accelerating the alcoholysis, and ultimately achieving further improvement in the activity and selectivity of the reaction.

[0031] The stability of the carbonylation reaction catalyst of the present invention refers not only to the stability of the physical properties and catalytic efficiency of the catalyst in a single reaction, but also to the stability of the catalytic efficiency when the catalyst is used as a reaction catalyst again after recovery after the catalyst reaction is completed. Common carbonylation reaction catalysts in this field will combine with other substances and lose their catalytic effect after the catalytic reaction is completed, and cannot be recycled by simple recycling means. The catalyst provided by the present invention will neither combine with other substances during the catalytic process nor lose its catalytic effect, and can be recycled by simple filtering and washing, and its catalytic efficiency is stable during the re-catalytic process.

[0032] According to a preferred embodiment of the present invention, when R 3 , R 4 , R 5 , R 6 When the bidentate phosphine ligand has both a bulky electron-rich group (such as di-tert-butylphosphine) and a basic group (such as tert-butylpyridylphosphine) that promotes the formation of active palladium, the bidentate phosphine ligand can more effectively promote the formation of active palladium and improve the activity of palladium, so that the subsequently prepared catalyst has the effect of better promoting the isomerization rate of 1,3-butadiene and accelerating alcoholysis, thereby further improving the catalytic performance of the supported catalyst for the carbonylation reaction.

[0033] According to a preferred embodiment of the present invention, R 1 and R 2 Each independently is C 1 -C 3 The above structure can further improve the stability of the bidentate phosphine ligand and the stability of the supported catalyst.

[0034] According to a preferred embodiment of the present invention, the bidentate phosphine ligand structure is selected from any one of the following structures:

[0035] Among them, EtO is ethoxy, MeO is methoxy, pph2 is diphenylphosphino, PCy 2 is dicyclohexylphosphine, PAd 2 It is a diadamantylphosphine group.

[0036]

[0037] In the present invention, there is no particular limitation on the preparation method of the bidentate phosphine ligand. As long as the bidentate phosphine ligand with the structure described above can be synthesized, it can be used in the present invention. Preferably, the preparation method of the bidentate phosphine ligand comprises:

[0038] (1) Mixing reactant A, magnesium rod and solvent (e.g. tetrahydrofuran) and reacting for a period of time to obtain a Grignard reagent;

[0039] (2) mixing the Grignard reagent obtained in step (1) with the reactant B solution, and reacting for a period of time to obtain a first solid;

[0040] (3) The first solid obtained in step (3) is mixed with reactant C, and after a period of reaction, the bidentate phosphine ligand is obtained.

[0041] Wherein, reactant A is 4-olefin-1,2-dichloromethylbenzene; reactant B has the general formula R 7 R 8 PCl, R 7 , R 8 The same or different from each other, and its selection range is the same as R 3 , R 4 , R 5 , R 6 The selection range is the same; the general formula of reactant C is HS-Z 2 -Si(OR 1 ) n (R 2 ) 3-n .

[0042] There is no particular limitation on the mixing method, reaction time, reaction temperature and other conditions of the above reaction, as long as the reaction can occur, and those skilled in the art can select them according to actual needs.

[0043] The second aspect of the present invention provides a supported catalyst, wherein the catalyst comprises the bidentate phosphine ligand described in the first aspect, palladium and a silicon-based mesoporous molecular sieve.

[0044] According to a preferred embodiment of the present invention, the bidentate phosphine ligand content is 0.1-1 mmol relative to 1 g of the mesoporous molecular sieve; the palladium content is 0.01-1 mmol relative to the total amount of 1 g of the silicon-based mesoporous molecular sieve and the bidentate phosphine ligand.

[0045] In the present invention, the specific type of the silicon-based mesoporous molecular sieve is not particularly limited, as long as it can be combined with the bidentate phosphine ligand.

[0046] According to a preferred embodiment of the present invention, the silicon-based mesoporous molecular sieve includes one or more of MCM-41, MCM-48, MCM-50, SBA-15, HMS, and MSU-1. The use of the above-mentioned molecular sieves is conducive to further improving the binding efficiency of the bidentate phosphine ligand and the mesoporous molecular sieve, increasing the loading amount and stability of the bidentate phosphine ligand, thereby further improving the catalytic performance of the catalyst.

[0047] According to a preferred embodiment of the present invention, the bidentate phosphine ligand content is 0.4-1mmol relative to 1g of mesoporous molecular sieve; the palladium content is 0.4-1mmol relative to the total amount of 1g of silicon-based mesoporous molecular sieve and bidentate phosphine ligand. The use of bidentate phosphine ligand and palladium at the above content has better complexation, so that the catalytic efficiency and stability of the supported catalyst are further improved. At the same time, the use of bidentate phosphine ligand and silicon-based mesoporous molecular sieve at the above content has a more suitable loading amount and better stability, so that the bidentate phosphine ligand can better cooperate with the palladium salt, thereby further improving the catalytic performance and stability of the supported catalyst.

[0048] The third aspect of the present invention provides a method for preparing the supported catalyst according to the second aspect, the method comprising:

[0049] (1) heating the silicon-based mesoporous molecular sieve to remove water and activate it to obtain a carrier;

[0050] (2) mixing the carrier obtained in step (1) with a bidentate phosphine ligand in the presence of a solvent, and then drying to obtain a first solid;

[0051] (3) In the presence of an organic solvent, the first solid obtained in step (2) is mixed with a palladium salt and dried to obtain the catalyst.

[0052] In the present invention, the specific type of palladium salt is not particularly limited, as long as it can be complexed with the bidentate phosphine ligand.

[0053] According to a preferred embodiment of the present invention, the palladium salt is Pd(TFA) 2 、Pd(OAc) 2 、Pd(acac) 2 , Pd 2 (dba) 3 , PdCl 2 , PdBr 2 One or more of the .

[0054] In the present invention, the selection range of the silicon-based mesoporous molecular sieve is the same as that described in the first aspect, and will not be repeated here.

[0055] According to a preferred embodiment of the present invention, the heating conditions in step (1) include: temperature 300-500° C., time 3-5 h.

[0056] According to a preferred embodiment of the present invention, in step (2), the solvent is selected from one or more of toluene, xylene, dichloromethane, chloroform, 1,2-dichloroethane, and acetone, preferably toluene. Using toluene as a solvent can further improve the stability of the combination of the carrier and the bidentate phosphine ligand, so that the supported catalyst has better catalytic performance and stability.

[0057] According to a preferred embodiment of the present invention, the mixing process in step (2) may or may not include heating and reflux, but preferably includes heating and reflux. The heating and reflux temperature should be determined according to the boiling point of the solvent, and the heating and reflux time is 8-12 hours.

[0058] According to a preferred embodiment of the present invention, the drying process in step (2) may include filtration and washing, or may not include, but preferably includes. The filtration method is not particularly limited, and can achieve solid-liquid separation, preferably sand core funnel filtration; the washing reagent is not particularly limited, and can achieve washing of the product, preferably dichloromethane; the drying method is not particularly limited, and can achieve drying of the product, preferably vacuum drying, the drying time is 2-6 hours, and the drying temperature is 60-120°C.

[0059] According to a preferred embodiment of the present invention, the first solid obtained in step (2) can be ground.

[0060] According to a preferred embodiment of the present invention, the selection range of the organic solvent described in step (3) is relatively wide, as long as the first solid obtained in step (2) can be reacted with the palladium salt, and those skilled in the art can make a selection according to actual conditions. Preferably, the organic solvent described in step (3) is one or more of toluene, dichloromethane, and acetone. The use of organic solvents of the types within the above preferred range is more conducive to the combination of bidentate phosphine ligands and palladium salts, thereby further improving the catalytic performance and stability of the supported catalyst.

[0061] According to a preferred embodiment of the present invention, the drying process in step (3) may include stirring, filtering and / or washing, preferably including. The filtering method is not particularly limited, and can achieve solid-liquid separation, preferably sand core funnel filtration; the washing reagent is not particularly limited, and can achieve washing of the product, preferably ether; the drying method is not particularly limited, and can achieve drying of the product, preferably vacuum drying, the drying time is 1.5-4h, and the drying temperature is 60-120°C.

[0062] The fourth aspect of the present invention provides an application of the supported catalyst of the second aspect in a carbonylation reaction; preferably, the application in the carbonylation of 1,3-butadiene to synthesize adipic acid diester compounds.

[0063] A fifth aspect of the present invention provides a method for synthesizing adipic acid diester compounds by carbonylation of 1,3-butadiene, the method comprising:

[0064] In the presence of CO, a supported catalyst, a catalyst promoter, an alcohol and a solution of 1,3-butadiene are contacted and a carbonylation reaction is carried out; wherein the supported catalyst is the supported catalyst described in the second aspect.

[0065] According to a preferred embodiment of the present invention, the added amount of the supported catalyst calculated as palladium atom is 0.001-0.01 mmol, preferably 0.005-0.01 mmol, relative to 1 mmol of 1,3-butadiene.

[0066] According to a preferred embodiment of the present invention, the catalyst promoter is selected from one or more of trifluoroacetic anhydride, sulfuric acid, and p-toluenesulfonic acid hydrate, preferably p-toluenesulfonic acid hydrate. Using p-toluenesulfonic acid hydrate as a catalyst promoter can further improve the catalytic effect of the catalyst, so that the reaction obtains a higher catalytic efficiency.

[0067] According to a preferred embodiment of the present invention, the amount of the catalyst promoter added is 0.01-0.05 mmol, preferably 0.02-0.04 mmol, calculated as hydrogen atoms, relative to 1 mmol of 1,3-butadiene.

[0068] According to a preferred embodiment of the present invention, the alcohol is selected from one or more of C1-C5 alcohols, preferably one or more of n-butanol, isopropanol, n-propanol, ethanol and methanol.

[0069] According to a preferred embodiment of the present invention, the amount of alcohol added is 1-5 mL, preferably 1-3 mL, relative to 1 mmol of 1,3-butadiene.

[0070] In the present invention, the specific type of the solvent of the 1,3-butadiene solution is not particularly limited, as long as it can dissolve 1,3-butadiene, and those skilled in the art can select it according to actual needs; preferably, the solvent is toluene.

[0071] In the present invention, the concentration of the 1,3-butadiene solution is not particularly limited, as long as 1,3-butadiene can react with other reactants, and those skilled in the art can select it according to actual needs; preferably, the concentration of the toluene solution is 0.1-1.5 mol / L.

[0072] According to a preferred embodiment of the present invention, the amount of alcohol added is 1-5 mL, preferably 1-3 mL, relative to 1 mmol of 1,3-butadiene. Using alcohol within the preferred range to react with the 1,3-butadiene solution can better generate the corresponding reaction product and obtain a higher reaction yield.

[0073] According to a preferred embodiment of the present invention, the reaction pressure of step (II) is 30-50 bar, the heating temperature is 100-140° C., and the heating time is 16-24 h.

[0074] The present invention will be described in detail below through preparation examples, embodiments and test examples.

[0075] The following preparation examples are used to illustrate the preparation of bidentate phosphine ligands.

[0076] Preparation Example 1

[0077] (1) At 0°C, 1 mol of 4-allyl-1,2-dichloromethylbenzene (reactant A), 52 g of magnesium stick and tetrahydrofuran solvent were mixed and reacted for 4 h to obtain a Grignard reagent.

[0078] (2) At 50° C., a Grignard reagent containing 0.5 mol of the product obtained in step (1) was mixed with 1 mol of tert-butylpyridinium phosphine chloride (reactant B), and the mixture was reacted for 20 h. The solvent was removed using a rotary evaporator to obtain a first solid.

[0079] (3) At 25° C., 0.3 mol of the first solid obtained in step (2) was mixed with 0.3 mol of mercaptopropyltriethoxysilane (reactant C) and reacted for 8 h to obtain the bidentate phosphine ligand 1a.

[0080] The NMR spectrum of the reaction product is shown below:

[0081] 1 H NMR (400 MHz, CDCl 3): δ8.28(dd,J=3.8,1.7Hz,2H),7.72(dtd,J=8.5,6.8,1.7Hz,2H),7.18(dt,J=6.7,1.3Hz,2 H),7.13(ddd,J=6.8,3.8,1.4Hz,2H),7.07(dt,J=7.6,1.0Hz,2H),6.99–6.90(m,1H),3.79(q ,J=7.5Hz,6H),3.74–3.61(m,2H),3.64–3.57(m,4H),2.68(tt,J=7.8,1.1Hz,4H),2.60–2.52 (m,2H),1.82(tt,J=7.8,6.4Hz,2H),1.72–1.62(m,9H),1.23(s,18H),0.84(t,J=9.1Hz,2H).

[0082] 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ156.35,156.32,150.31,150.30,138.54,138.41,137.46,137.07,137.05,132.70,132.69,130.78,129.79,129.11,121. 56,121.53,58.38,34.58,33.06,31.74,30.22,30.17,29.08,28.11,28.08,27.99,27.97,27.95,27.93,23.41,18.30,10.46.

[0083] Preparation Example 2

[0084] The preparation steps are the same as those in Preparation Example 1, wherein the types and amounts of reactants A, B and C are shown in Table 1.

[0085] The reaction product of this preparation example is bidentate phosphine ligand 1b, and its NMR spectrum is shown below:

[0086] 1 H NMR (400 MHz, CDCl 3): δ8.28(dd,J=3.7,1.7Hz,1H),7.72(dtd,J=8.5,6.8,1.7Hz,1H),7.18(dt,J=6.8,1.4Hz,1H),7.13(d dd,J=6.8,3.7,1.5Hz,1H),7.07(dt,J=7.6,1.0Hz,1H),6.96(ddt,J=7.7,2.1,1.0Hz,1H),6.92(dq,J=2 .2,1.0Hz,1H),3.79(q,J=7.5Hz,6H),2.68(tt,J=7.8,1.1Hz,6H),2.60–2.52(m,4H),1.82(tt,J=7.8, 6.4Hz,2H),1.72–1.62(m,2H),1.22(t,J=7.4Hz,9H),1.17(s,9H),1.05(s,18H),0.84(t,J=9.1Hz,2H).

[0087] 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ156.32,150.30,139.16,137.75,137.44,137.05,132.69,130.77,130.69,129.11,121.53,58 .38,34.58,33.06,31.74,30.92,30.17,29.17,29.08,28.04,27.93,23.49,23.41,18.30,10.46.

[0088] Preparation Example 3

[0089] The preparation steps are the same as those in Preparation Example 1, wherein the types and amounts of reactants A, B and C are shown in Table 1.

[0090] The reaction product of this preparation example is bidentate phosphine ligand 1c, and its NMR spectrum is shown below:

[0091] 1 H NMR (400 MHz, CDCl 3): δ6.99–6.90(m,3H),3.79(q,J=7.5Hz,6H),2.95–2.89(m,1H),2.89–2.74(m,1H),2.68(tt,J=7.7,1.0Hz,4H),2.60 –2.52(m,4H),1.82(tt,J=7.8,6.4Hz,2H),1.72–1.62(m,2H),1.25–1.19(m,9H),1.05(s,36H),0.84(t,J=9.1Hz,2H).

[0092] 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ138.08,137.67,137.44,131.20,130.71,129.04,58.38,34.58,33.06,31.74,31.05,30.99,3 0.92,29.37,29.34,29.30,29.27,29.24,29.20,29.17,29.08,23.59,23.49,23.41,18.30,10.46.

[0093] Preparation Example 4

[0094] The preparation steps are the same as those in Preparation Example 1, wherein the types and amounts of reactants A, B and C are shown in Table 1.

[0095] The reaction product of this preparation example is bidentate phosphine ligand 1d, and its NMR spectrum is shown below:

[0096] 1 H NMR (400 MHz, CDCl 3 ): δ7.42–7.25(m,12H),7.09(dt,J=7.4,1.0Hz,10H),6.99–6.92(m,1H),3.79(q,J=7.5Hz,6H),2.68(tt,J=7.8,1.1Hz ,6H),2.60–2.52(m,4H),1.82(tt,J=7.8,6.4Hz,2H),1.72–1.62(m,2H),1.22(t,J=7.4Hz,9H),0.84(t,J=9.1Hz,2H).

[0097] 13 C{ 1 H}NMR (100MHz, CDCl 3): δ139.59,139.13,138.53,138.45,138.40,137.45,133.45,130.82,129.89,129.11,128.70,128. 67,128.63,128.56,128.54,58.38,34.58,33.06,32.11,31.99,31.74,29.08,23.41,18.30,10.46.

[0098] Preparation Example 5

[0099] The preparation steps are the same as those in Preparation Example 1, wherein the types and amounts of reactants A, B and C are shown in Table 1.

[0100] The reaction product of this preparation example is bidentate phosphine ligand 1e, and its NMR spectrum is shown below:

[0101] 1 H NMR (400 MHz, CDCl 3 ): δ6.99–6.92(m,2H), 3.79(q,J=7.5Hz,6H),,2.68(tt,J=7.7,1.0Hz,6H),2.60–2.52(m, 4H), 2.07–1.99 (m, 14H), 1.65–1.60 (m, 51H), 1.22 (t, J = 7.4Hz, 9H), 0.84 (t, J = 9.1Hz, 2H).

[0102] 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ138.91,138.89,137.44,131.25,130.71,129.04,58.38,39.00,38.94,38 .88,36.70,36.63,36.49,36.42,36.35,36.01,35.80,35.73,35.65,35.59,3 5.51,35.44,35.30,35.25,35.04,34.97,34.58,33.06,31.74,30.31,30.25,30.20,30.14,30.09,30.04,29.98,29.08,25.33,25.21,23.41,18.30,10.46.

[0103] Preparation Example 6

[0104] The preparation steps are the same as those in Preparation Example 1, wherein the types and amounts of reactants A, B and C are shown in Table 1.

[0105] The reaction product of this preparation example is a bidentate phosphine ligand 1f, and its NMR spectrum is shown below:

[0106] 1 H NMR (400 MHz, CDCl 3 ): δ7.03(dt,J=7.7,1.0Hz,1H),6.96(ddt,J=7.7,2.1,1.0Hz,1H),6.86(dp,J=2.1,1.0Hz,1H),3.79(q, J=7.5Hz,6H),2.95(dd,J=13.6,1.0Hz,6H),2.86(ddd,J=13.7,11.5,1.1Hz,4H),2.24–2.15(m,2H),1.59 -1.22(m,55H),0.84(t,J=9.1Hz,2H).

[0107] 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ139.58,139.44,137.44,129.90,129.42,129.04,58.38,36.59,36.52,36.45,34.58,33.06,31.74,30.47,30.45,2 9.59,29.54,29.50,29.45,29.41,29.08,27.12,27.10,27.08,27.07,27.05,26.50,26.49,26.48,23.41,18.30,10.46.

[0108] Preparation Example 7

[0109] The preparation steps are the same as those in Preparation Example 1, wherein the types and amounts of reactants A, B and C are shown in Table 1.

[0110] The reaction product of this preparation example is a bidentate phosphine ligand 1g, and its NMR spectrum is shown below:

[0111] 1 H NMR (400 MHz, CDCl 3): δ6.99–6.90(m,3H),3.58(s,9H),2.92(dd,J=13.7,1.0Hz,2H),2.83(dddd,J=37.5,13.7,11.7,0.9Hz,2H),2.68(tt,J =7.8,1.1Hz,2H),2.60–2.52(m,4H),1.82(tt,J=7.8,6.4Hz,2H),1.71–1.61(m,2H),1.05(s,36H),0.84(t,J=9.2Hz,2H).

[0112] 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ138.08,137.67,137.44,131.20,130.71,129.04,50.28,34.58,33.06,31.74,31.05,30.9 9,30.92,29.37,29.34,29.30,29.27,29.24,29.20,29.17,29.08,23.59,23.55,23.49,8.05.

[0113] Preparation Example 8

[0114] The preparation steps are the same as those in Preparation Example 1, wherein the types and amounts of reactants A, B and C are shown in Table 1.

[0115] The reaction product of this preparation example is bidentate phosphine ligand 1h, and its NMR spectrum is shown below:

[0116] 1 H NMR (400 MHz, CDCl 3): δ8.28(dd,J=3.7,1.7Hz,1H),7.72(dtd,J=8.5,6.8,1.7Hz,1H),7.18(dt,J=6.8,1.4Hz,1H),7.13(d dd,J=6.8,3.8,1.5Hz,1H),7.07(dt,J=7.6,1.0Hz,1H),6.96(ddt,J=7.7,2.1,1.1Hz,1H),6.92(dp,J= 2.0,1.0Hz,1H),3.79(q,J=7.5Hz,6H),2.64–2.54(m,6H),2.54(d,J=9.8Hz,4H),1.72–1.58(m,2H),1. 57–1.48(m,2H),1.40(pd,J=6.8,1.1Hz,2H),1.25–1.15(m,11H),1.05(s,27H),0.84(t,J=9.1Hz,2H).

[0117] 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ156.32,150.30,139.16,138.58,137.75,137.05,132.69,130.77,130.70,129.04,121.53,58.38,35 .52,33.01,31.99,30.92,30.32,30.17,29.19,29.17,28.04,27.99,27.93,23.49,23.41,18.30,10.46.

[0118] Table 1

[0119]

[0120] The following examples are used to illustrate the preparation of supported catalysts.

[0121] Example 1

[0122] (1) 2 g of MCM-41 molecular sieve was placed in a high temperature tube furnace and heated at 400°C for 4 h to remove water and activate it;

[0123] (2) 1 g of dehydrated and activated MCM-41 molecular sieve and 0.5 mmol of bidentate phosphine ligand with structure 1a were placed in 30 ml of anhydrous toluene solution and heated under reflux for 10 h. After the reaction was completed, the filter was filtered with a sand core funnel and the filter cake was washed with acetone;

[0124] (3) The filtered and washed solid was placed in a vacuum drying oven at 80° C. and vacuum dried for 4 h. After drying, the silicon-based bidentate phosphine ligand MCM-41-2P was obtained by grinding.

[0125] (4) Take 1 gram of the bidentate phosphine ligand MCM-41-2P obtained in step (3) and 0.5 mmol Pd(TFA) 2 The reaction mixture was stirred in 40 ml of toluene solution for 24 h. After the reaction was completed, the mixture was filtered and the filter cake was washed with ether and dried in a vacuum oven to obtain the supported carbonylation catalyst S1. Figure 1 As described above, the catalyst morphology in the figure is regular, showing a tight and regular striped pattern, which is consistent with the morphology of the supported mesoporous molecular sieve catalyst.

[0126] Example 2

[0127] The preparation steps are the same as those of Example 1, wherein the bidentate phosphine ligand with structure 1a is replaced with a bidentate phosphine ligand with structure 1b, and finally a supported catalyst S2 is obtained.

[0128] Example 3

[0129] The preparation steps are the same as those of Example 1, wherein the bidentate phosphine ligand with structure 1a is replaced with a bidentate phosphine ligand with structure 1c, and finally a supported catalyst S3 is obtained.

[0130] Example 4

[0131] The preparation steps are the same as those in Example 1, wherein the bidentate phosphine ligand with structure 1a is replaced with a bidentate phosphine ligand with structure 1d, and finally a supported catalyst S4 is obtained.

[0132] Example 5

[0133] The preparation steps are the same as those in Example 1, wherein the bidentate phosphine ligand with structure 1a is replaced with a bidentate phosphine ligand with structure 1e, and finally a supported catalyst S5 is obtained.

[0134] Example 6

[0135] The preparation steps are the same as those in Example 1, wherein the bidentate phosphine ligand with structure 1a is replaced with a bidentate phosphine ligand with structure 1f, and finally a supported catalyst S6 is obtained.

[0136] Example 7

[0137] The preparation steps are the same as those of Example 1, wherein the bidentate phosphine ligand with structure 1a is replaced with a bidentate phosphine ligand with structure 1g, and finally the supported catalyst S7 is obtained.

[0138] Example 8

[0139] The preparation steps are the same as those in Example 1, wherein the bidentate phosphine ligand with structure 1a is replaced with a bidentate phosphine ligand with structure 1h, and finally a supported catalyst S8 is obtained.

[0140] Example 9

[0141] The preparation steps are the same as those of Example 1, wherein the bidentate phosphine ligand of structure 1a is replaced by a bidentate phosphine ligand of structure 1b, Pd(TFA) 2 Replaced with Pd(OAc) 2 , and finally the supported catalyst S9 was obtained.

[0142] The following test examples are used to illustrate the testing of the catalytic performance of the supported catalyst.

[0143] Test Example 1

[0144] Catalyst S1 (0.005 mmol in terms of palladium atoms) and p-toluenesulfonic acid hydrate (0.02 mmol in terms of hydrogen atoms) were added to a high-pressure reactor, 2 mL of n-butanol was added using a syringe, and then butadiene (1 mmol, toluene solution) was added to the reactor.

[0145] Before the reaction, the autoclave was ventilated with carbon monoxide three times and then carbon monoxide was introduced to a reaction pressure of 40 bar. The reaction was carried out at 120° C. for 24 h. After the reaction was completed, the autoclave was cooled to room temperature and the pressure was slowly released.

[0146] The yield of dibutyl adipate was determined to be 84% by gas chromatography using mesitylene as the internal standard.

[0147] 1 H NMR (400 MHz, CDCl 3 ): δ4.05(t,J=6.7Hz,4H),2.40-2.17(m,4H),1.74-1.45(m,8H),1.46-1.25(m,4H),0.91(t,J=7.3Hz,6H)ppm. 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ173.6,64.3,34.1,30.8,24.6,19.3,13.8ppm.

[0148] Test Example 2

[0149] The test steps were the same as those of Test Example 1, with the catalyst S1 being replaced by catalyst S2.

[0150] The yield of dibutyl adipate was determined to be 87% by gas chromatography using mesitylene as the internal standard. 1 H NMR (400 MHz, CDCl 3): δ4.05(t,J=6.7Hz,4H),2.40-2.17(m,4H),1.74-1.45(m,8H),1.46-1.25(m,4H),0.91(t,J=7.3Hz,6H)ppm. 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ173.6,64.3,34.1,30.8,24.6,19.3,13.8ppm.

[0151] Test Example 3

[0152] The test steps were the same as those of Test Example 1, wherein the catalyst S1 was replaced by the catalyst S3. The yield of the product dibutyl adipate was determined by gas chromatography using mesitylene as the internal standard to be 82%.

[0153] 1 H NMR (400 MHz, CDCl 3 ): δ4.05(t,J=6.7Hz,4H),2.40-2.17(m,4H),1.74-1.45(m,8H),1.46-1.25(m,4H),0.91(t,J=7.3Hz,6H)ppm. 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ173.6,64.3,34.1,30.8,24.6,19.3,13.8ppm.

[0154] Test Example 4

[0155] The test steps were the same as those of Test Example 1, wherein the catalyst S1 was replaced by the catalyst S4. The yield of the product dibutyl adipate was determined by gas chromatography using mesitylene as the internal standard to be 71%.

[0156] 1 H NMR (400 MHz, CDCl 3 ): δ4.05(t,J=6.7Hz,4H),2.40-2.17(m,4H),1.74-1.45(m,8H),1.46-1.25(m,4H),0.91(t,J=7.3Hz,6H)ppm. 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ173.6,64.3,34.1,30.8,24.6,19.3,13.8ppm.

[0157] Test Example 5

[0158] The test steps were the same as those of Test Example 1, wherein the catalyst S1 was replaced by the catalyst S5. The yield of the product dibutyl adipate was determined by gas chromatography using mesitylene as the internal standard to be 76%.

[0159] 1 H NMR (400 MHz, CDCl 3 ): δ4.05(t,J=6.7Hz,4H),2.40-2.17(m,4H),1.74-1.45(m,8H),1.46-1.25(m,4H),0.91(t,J=7.3Hz,6H)ppm. 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ173.6,64.3,34.1,30.8,24.6,19.3,13.8ppm.

[0160] Test Example 6

[0161] The test steps were the same as those of Test Example 1, wherein the catalyst S1 was replaced by the catalyst S6. The yield of the product dibutyl adipate was determined by gas chromatography using mesitylene as the internal standard to be 70%.

[0162] 1 H NMR (400 MHz, CDCl 3 ): δ4.05(t,J=6.7Hz,4H),2.40-2.17(m,4H),1.74-1.45(m,8H),1.46-1.25(m,4H),0.91(t,J=7.3Hz,6H)ppm. 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ173.6,64.3,34.1,30.8,24.6,19.3,13.8ppm.

[0163] Test Example 7

[0164] The test steps were the same as those of Test Example 1, wherein the catalyst S1 was replaced by the catalyst S7. The yield of the product dibutyl adipate was determined by gas chromatography using mesitylene as the internal standard to be 81%.

[0165] 1 H NMR (400 MHz, CDCl 3 ): δ4.05(t,J=6.7Hz,4H),2.40-2.17(m,4H),1.74-1.45(m,8H),1.46-1.25(m,4H),0.91(t,J=7.3Hz,6H)ppm. 13 C{ 1H}NMR (100MHz, CDCl 3 ): δ173.6,64.3,34.1,30.8,24.6,19.3,13.8ppm.

[0166] Test Example 8

[0167] The test steps were the same as those of Test Example 1, wherein the catalyst S1 was replaced by the catalyst S8. The yield of the product dibutyl adipate was determined by gas chromatography using mesitylene as the internal standard to be 85%.

[0168] 1 H NMR (400 MHz, CDCl 3 ): δ4.05(t,J=6.7Hz,4H),2.40-2.17(m,4H),1.74-1.45(m,8H),1.46-1.25(m,4H),0.91(t,J=7.3Hz,6H)ppm. 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ173.6,64.3,34.1,30.8,24.6,19.3,13.8ppm.

[0169] Test Example 9

[0170] The test steps were the same as those of Test Example 1, wherein the catalyst S1 was replaced by the catalyst S9. The yield of the product dibutyl adipate was determined by gas chromatography using mesitylene as the internal standard to be 79%.

[0171] 1 H NMR (400 MHz, CDCl 3 ): δ4.05(t,J=6.7Hz,4H),2.40-2.17(m,4H),1.74-1.45(m,8H),1.46-1.25(m,4H),0.91(t,J=7.3Hz,6H)ppm. 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ173.6,64.3,34.1,30.8,24.6,19.3,13.8ppm.

[0172] Test Example 10

[0173] The test steps were the same as those of Test Example 1, wherein catalyst S1 was replaced by catalyst S2, and n-butanol was replaced by methanol.

[0174] The yield of dimethyl adipate was determined to be 81% by gas chromatography using mesitylene as the internal standard.

[0175] 1 H NMR (400 MHz, CDCl 3 ): δ3.52(s,6H),2.23-2.16(m,4H),1.57-1.47(m,4H)ppm. 13 C{ 1 H}NMR (100MHz, CDCl 3 ):δ173.5,51.3,33.4,24.2.

[0176] Test Example 11

[0177] The test steps were the same as those of Test Example 1, wherein catalyst S1 was replaced by catalyst S2, and n-butanol was replaced by ethanol.

[0178] The yield of diethyl adipate was determined to be 82% by gas chromatography using mesitylene as the internal standard.

[0179] 1 H NMR (400 MHz, CDCl 3 ): δ4.11(q,J=7.1Hz,4H),2.35-2.25(m,4H),1.70-1.58(m,4H),1.24(t,J=7.1Hz,6H)ppm.

[0180] 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ173.5,60.4,34.1,24.5,14.4ppm.

[0181] Test Example 12

[0182] The test steps were the same as those of Test Example 1, wherein catalyst S1 was replaced by catalyst S2, and n-butanol was replaced by n-propanol.

[0183] The yield of dipropyl adipate was determined to be 88% by gas chromatography using mesitylene as the internal standard.

[0184] 1 H NMR (400 MHz, CDCl 3 ): δ3.96(t,J=6.7Hz,4H),2.30-2.20(m,4H),1.67-1.47(m,8H),0.87(t,J=7.4Hz,6H)ppm. 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ173.4,65.9,33.9,24.5,22.0,10.4ppm.

[0185] Test Example 13

[0186] The test steps were the same as those of Test Example 1, wherein catalyst S1 was replaced by catalyst S2, and n-butanol was replaced by isopropanol.

[0187] The yield of diisopropyl adipate was determined to be 84% by gas chromatography using mesitylene as an internal standard.

[0188] 1 H NMR (400 MHz, CDCl 3 ): δ5.06-4.93(m,2H),2.31-2.24(m,4H),1.66-1.60(m,4H),1.22(d,J=6.3Hz,12H)ppm. 13 C{ 1 H}NMR (100MHz, CDCl 3 ): δ173.0,67.7,34.5,24.6,22.0ppm.

[0189] Test Case 14

[0190] (1) The test steps are the same as those in Test Example 2.

[0191] (2) Using mesitylene as the internal standard, the yield of dibutyl adipate was determined by gas chromatography.

[0192] (3) The reaction solution was filtered to obtain a solid, which was washed several times with distilled water and ether, and dried at 80° C. for 3 h to obtain a recovered catalyst.

[0193] (4) Repeat the above steps six times.

[0194] The results are shown in Table 1.

[0195] Table 1

[0196]

[0197] It can be seen from the above results that the catalyst of the present invention is easy to recycle and can maintain a high product yield when recycled more than six times.

[0198] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A bidentate phosphine ligand, It is characterized in that The general formula of the bidentate phosphine ligand is AZ 1 -SZ 2 -Si(OR 1 ) n (R 2 ) 3-n ; Among them, the general formula of A is R 3 , R 4 , R 5 , R 6 are the same as or different from each other and are each independently selected from C1-C10 straight or branched alkyl, C1-C10 alkoxy, C3-C10 cycloalkyl, C2-C10 heterocycloalkyl, substituted or unsubstituted C6-C20 aryl, C6-C20 aryloxy or C6-C20 heteroaryl; Z 1 and Z 2 Each is independently an alkylene group; R 1 and R 2 Each is independently an alkyl group; n is a positive integer of 1-3.

2. The bidentate phosphine ligand according to claim 1, in, Z 1 For -(CH 2 ) a -, a is a positive integer ranging from 3 to 11; Z 2 For -(CH 2 ) b -, b is a positive integer ranging from 1 to 3; Preferably, R 3 , R 4 , R 5 , R 6 each independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, n-hexyl, n-heptyl, n-octyl, isooctyl, n-nonyl, adamantyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, phenyl, fluorophenyl, bromophenyl, chlorophenyl, o-tolyl, p-tolyl, m-tolyl, o-ethylphenyl, p-ethylphenyl, m-ethylphenyl, o-isopropylphenyl, p-isopropylphenyl, m-isopropylphenyl, methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, nonyloxy, decyloxy, 2-pyridyl, phenoxy, methylphenoxy, ethylphenoxy, n-propylphenoxy, isopropylphenoxy, and 2-thienyl; More preferably, R 3 , R 4 , R 5 , R 6 Each is independently selected from n-butyl, isobutyl, sec-butyl, tert-butyl, adamantyl, cyclobutane, cyclopentane, cyclohexane, cycloheptane, fluorophenyl, bromophenyl, phenyl, propoxy, butoxy, pentyloxy, 2-pyridyl, phenoxy, n-propylphenoxy or 2-thienyl; and / or, R 1 and R 2 Each independently is C 1 -C 3 The alkyl group; Preferably, the bidentate phosphine ligand structure is selected from any one of the following structures.

3. A supported catalyst, It is characterized in that The catalyst comprises a bidentate phosphine ligand, palladium and a silicon-based mesoporous molecular sieve; Wherein, the bidentate phosphine ligand is the bidentate phosphine ligand according to claim 1 or 2; Preferably, the content of bidentate phosphine ligand is 0.01-1 mmol relative to 1 g of the mesoporous molecular sieve; and the content of palladium is 0.01-1 mmol relative to the total amount of 1 g of the silicon-based mesoporous molecular sieve and the bidentate phosphine ligand.

4. The catalyst according to claim 3, in, The silicon-based mesoporous molecular sieve includes one or more of MCM-41, MCM-48, MCM-50, SBA-15, HMS, and MSU-1; Preferably, the content of bidentate phosphine ligand is 0.4-1 mmol relative to 1 g of silicon-based mesoporous molecular sieve; and the content of palladium is 0.4-1 mmol relative to the total amount of 1 g of silicon-based mesoporous molecular sieve and bidentate phosphine ligand.

5. A method for preparing the catalyst according to claim 3 or 4, wherein the method The following steps are involved: (1) heating the silicon-based mesoporous molecular sieve to remove water and activate it to obtain a carrier; (2) mixing the carrier obtained in step (1) with a bidentate phosphine ligand in the presence of a solvent, and then drying to obtain a first solid; (3) In the presence of an organic solvent, the first solid obtained in step (2) is mixed with a palladium salt and dried to obtain the catalyst.

6. The method according to claim 5, in, The palladium salt is Pd(TFA) 2 、Pd(OAc) 2 、Pd(acac) 2 , Pd 2 (dba) 3 , PdCl 2 , PdBr 2 One or more of the .

7. The method according to claim 5, in, In step (2), the solvent is selected from one or more of toluene, xylene, dichloromethane, chloroform, 1,2-dichloroethane, and acetone, preferably toluene; Preferably, the organic solvent in step (3) is selected from one or more of toluene, xylene, dichloromethane, chloroform, 1,2-dichloroethane and acetone, preferably one or more of toluene, dichloromethane and acetone.

8. Use of the catalyst according to claim 3 or 4 in a carbonylation reaction; preferably, use in the carbonylation of 1,3-butadiene to synthesize adipic acid diester compounds.

9. A method for synthesizing adipic acid diester compounds by carbonylation of 1,3-butadiene, It is characterized in that The method includes: In the presence of CO, a supported catalyst, a catalyst promoter, an alcohol and a solution of 1,3-butadiene are contacted and a carbonylation reaction is carried out; Wherein, the supported catalyst is the supported catalyst according to claim 3 or 4.

10. The method according to claim 9, in, The amount of the supported catalyst added is 0.001-0.01 mmol, preferably 0.005-0.01 mmol, calculated as palladium atoms, relative to 1 mmol of 1,3-butadiene; Preferably, the catalyst promoter is selected from one or more of trifluoroacetic anhydride, sulfuric acid, and p-toluenesulfonic acid hydrate, preferably p-toluenesulfonic acid hydrate; Preferably, the amount of the catalyst promoter added is 0.01-0.05 mmol, preferably 0.02-0.04 mmol, calculated as hydrogen atoms, relative to 1 mmol of 1,3-butadiene; Preferably, the alcohol is selected from one or more of C1-C5 alcohols, preferably one or more of n-butanol, isopropanol, n-propanol, ethanol, and methanol; Preferably, the amount of alcohol added is 1-5 mL, preferably 1-3 mL, relative to 1 mmol of 1,3-butadiene; Preferably, the reaction pressure of the reaction is 30-50 bar, the reaction temperature is 100-140° C., and the reaction time is 16-24 h.

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