Synthesis method of 2-aryl-5-alkyl-3-pyridyl thiophene

Abstract

The invention discloses a synthesis method of 2-aryl-5-alkyl-3-pyridylthiophene, which comprises the following steps: by taking 3-pyridylthiophene, alkyl bromide and chlorobenzene as raw materials, catalyzing by using a ruthenium catalyst, and carrying out a three-component reaction by using a one-pot method to prepare the 2-aryl-5-alkyl-3-pyridylthiophene. According to the method, selective carbon-hydrogen bond activation of C2 and C5 sites of 3-pyridyl thiophene is realized by utilizing a ruthenium catalyst, so that precise bifunctional modification is completed in a single reaction system. According to the invention, the 2-aryl-5-alkyl-3-pyridyl thiophene with a clear structure is successfully constructed, and the technical vacancy of related fields in the aspect of regioselective one-pot bifunctionalization is made up. Compared with a traditional fractional step method, the method has the advantages of simplified reaction steps, convenience in operation, good functional group compatibility, relatively high chemical selectivity, regioselectivity, atom economy and the like, is suitable for efficient construction of various heterocyclic compounds, and has a good application prospect.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of organic synthesis, and particularly relates to a synthesis method of 2-aryl-5-alkyl-3-pyridyl thiophene. BACKGROUND

[0002] Thiophene compounds are widely used in the fields of drug chemistry, pesticide chemistry, material chemistry and functional molecule development due to their unique heterocyclic structure and excellent electronic properties. In particular, thiophene skeletons containing various functional groups are embodied in a plurality of marketed drug molecules, and have a key influence on pharmacodynamic regulation, target selectivity and metabolic stability. Therefore, constructing thiophene derivatives with diverse structures, high functional group density and controllable positions is an important research direction in current organic synthesis and drug molecule design.

[0003] In the prior art, functionalization methods for aromatic heterocyclic structures have been widely studied and reported, including transition metal-catalyzed C-H bond activation / functionalization reactions, cross-coupling reactions and nucleophilic aromatic substitution reactions (S N Ar) and the like. These methods have important advantages in constructing single-substituted heterocyclic compounds, and can efficiently obtain a series of single-functionalized products from readily available halogenated aromatic hydrocarbons or heteroaromatic rings. However, the above strategies are mostly dependent on pre-introduced halogen or directing groups, and their controllability is limited, and usually only one substituent can be introduced at a single position of the aromatic ring or heterocycle. For the construction of complex molecular structures, the continuous installation of multi-site and multi-functional groups still faces great challenges.

[0004] In particular, for thiophene skeletons, due to the different electronic density distribution at multiple sites, how to realize the continuous functionalization with regioselectivity without pre-installing a directing group and without relying on multi-step protection-deprotection operations is one of the key problems currently concerned by synthetic chemists. Although traditional cross-coupling and S N Ar reactions are reliable, they rely on the limited site of the substrate structure itself, making it more difficult to realize multi-site regulation in thiophene and other heterocycle fusion systems.

[0005] In recent years, transition-metal-catalyzed remote C-H activation technology has provided new tools. For example, in 2015, the Ackermann group developed a ruthenium-catalyzed system assisted by an amino acid ligand, which realized the 2-phenylpyridine meta C-H alkylation reaction; subsequently, the system was also expanded under photocatalytic conditions. This method shows the possibility of realizing the selective transformation of non-ortho C-H bonds in heterocyclic systems. However, for more complex 3-pyridyl thiophene, the site electronic effect is more diverse, and how to realize the alkylation of its meta position (i.e. the thiophene C-H site connected to the pyridine ring) is still rarely reported in the existing literature. In addition, the research on the one-pot strategy for introducing two different types of functional groups (such as alkyl and aryl) to construct a multi-heterocyclic fused system is still relatively limited. The one-pot method has the advantages of simple operation, reduced steps, resource saving, and improved atom economy. However, due to the large difference in the reactivity and site selectivity of the reactants in the system, it is difficult to achieve high regioselectivity and high compatibility.

[0006] In view of the limited progress in the current technology in the dual functionalization of thiophene systems, especially the 3-pyridyl thiophene framework, especially the lack of a one-pot method for using bromoalkane and chloroarene and other common functionalization reagents to realize regioselective C-H alkylation and arylation, therefore, developing an efficient, simple and substrate-adaptable 3-pyridyl thiophene dual functionalization strategy is of great significance for the construction of 2-aryl-5-alkyl-3-pyridyl thiophene and other multi-heterocyclic structures. SUMMARY

[0007] The technical problem to be solved by the present application is to provide a simple and easy-to-operate synthesis method of 2-aryl-5-alkyl-3-pyridyl thiophene, which has good compatibility with various functional groups and excellent chemical selectivity, regioselectivity and high atom economy.

[0008] To solve the above technical problems, the following technical solutions are adopted in the present application:

[0009] The synthesis method of 2-aryl-5-alkyl-3-pyridyl thiophene uses 3-pyridyl thiophene, bromoalkane and chlorobenzene as raw materials, uses a ruthenium catalyst for catalysis, and prepares 2-aryl-5-alkyl-3-pyridyl thiophene through a one-pot three-component reaction.

[0010] The above synthesis method adds compound 1, compound 2, compound 3, a ruthenium catalyst, a base and a solvent in a reactor, stirs under argon atmosphere at a certain temperature for a certain time, cools to room temperature after the reaction is completed, concentrates, and then purifies the crude mixture through silica gel column chromatography to obtain 2-aryl-5-alkyl-3-pyridyl thiophene; wherein compound 1 is a 3-pyridyl thiophene compound, compound 2 is a bromoalkane, and compound 3 is chlorobenzene.

[0011] The reaction conforms to the following reaction formula:

[0012] .

[0013] The ruthenium catalyst is one or more of a combination of dichloro (pentamethylcyclopentadienyl) ruthenium polymer, triphenylphosphine chloro ruthenium, tris (acetylacetate) ruthenium, dichloro dicarbonyl bis (triphenylphosphine) ruthenium, ruthenium trichloride hydrate, dichloro bis (4-methyl isopropyl phenyl) ruthenium; the base is one or more of a combination of sodium carbonate, potassium dihydrogen phosphate, potassium benzoate, lithium acetate, potassium tert-pentanoate, potassium phosphate, sodium bicarbonate, sodium trifluoroacetate, potassium acetate, disodium hydrogen phosphate, lithium carbonate, sodium p-toluenesulfonate, cesium carbonate, cesium acetate, potassium trifluoroacetate, sodium phosphate, sodium benzenesulfonate, sodium dihydrogen phosphate, sodium acetate, lithium trifluoroacetate; the solvent is one or more of a combination of hexafluoroisopropyl alcohol, tetrahydrofuran, toluene, ethanol, dimethyl sulfoxide, 1, 2-dichloroethane, trifluorotoluene, tert-butyl alcohol, chlorobenzene, 1, 4-dioxane, acetonitrile, isopropanol, methanol, dichloromethane.

[0014] The ruthenium catalyst is dichloro bis (4-methyl isopropyl phenyl) ruthenium, the base is sodium acetate, and the solvent is chlorobenzene.

[0015] The molar ratio of compound 1 to compound 2 is 1:1-6.

[0016] The reaction temperature is 0-150 °C, and the reaction time is 0-48 h.

[0017] The molar ratio of compound 1 to compound 2 is 1:1.2, the reaction temperature is 130 °C, and the reaction time is 16 h.

[0018] The reactor is a Schlenk tube.

[0019] In view of the technical bottleneck that the regioselectivity is difficult to control in the multi-site functionalization of 3-pyridyl thiophene, the inventors establish a synthesis method of 2-aryl-5-alkyl-3-pyridyl thiophene. The 2-aryl-5-alkyl-3-pyridyl thiophene is prepared by a one-pot three-component reaction using 3-pyridyl thiophene, bromoalkane and chlorobenzene as raw materials and using a ruthenium catalyst for catalysis. The method realizes selective carbon-hydrogen bond activation at the C2 and C5 sites of 3-pyridyl thiophene by using a ruthenium catalyst, so as to complete precise double functionalization modification in a single reaction system. The 2-aryl-5-alkyl-3-pyridyl thiophene with a clear structure is successfully constructed, which fills the technical gap in the one-pot double functionalization in terms of regioselectivity in the related field. Compared with the traditional step-by-step method, the method has the advantages of simplified reaction steps, convenient operation, good functional group compatibility, high chemical selectivity, regioselectivity and atomic economy, and is suitable for efficient construction of various heterocyclic compounds, and has good application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The hydrogen spectrum of the product obtained in Example 1.

[0021] Figure 2 The carbon spectrum of the product obtained in Example 1.

[0022] Figure 3 The hydrogen spectrum of the product obtained in Example 2.

[0023] Figure 4 The carbon spectrum of the product obtained in Example 2.

[0024] Figure 5 The hydrogen spectrum of the product obtained in Example 3.

[0025] Figure 6 The carbon spectrum of the product obtained in Example 3.

[0026] Figure 7 The hydrogen spectrum of the product obtained in Example 4.

[0027] Figure 8 The carbon spectrum of the product obtained in Example 4.

[0028] Figure 9 The hydrogen spectrum of the product obtained in Example 5.

[0029] Figure 10 The carbon spectrum of the product obtained in Example 5.

[0030] Figure 11 The hydrogen spectrum of the product obtained in Example 6.

[0031] Figure 12 The carbon spectrum of the product obtained in Example 6.

[0032] Figure 13 The hydrogen spectrum of the product obtained in Example 7.

[0033] Figure 14 The carbon spectrum of the product obtained in Example 7.

[0034] Figure 15 The hydrogen spectrum of the product obtained in Example 8.

[0035] Figure 16 The carbon spectrum of the product obtained in Example 8. DETAILED DESCRIPTION

[0036] Example 1

[0037] Sodium acetate (1.2 mmol, 4 equiv.), 3-pyridyl thiophene (0.3 mmol, 1 equiv.), [Ru(p-cymene)Cl2]2(0.015 mmol, 5 mol%), methyl 2-bromoisobutyrate (1.2 equiv.) and chlorobenzene (1 mL) were added sequentially into a 15 mL oven-dried Schlenk tube. The reaction mixture was stirred at 130 °C for 16 hours under an argon atmosphere. After cooling to room temperature and concentration, the crude mixture was purified by silica gel column chromatography (PE:EA = 9:1) to give the desired product.

[0038] The hydrogen spectrum and carbon spectrum of the product obtained are shown in Figure 1 and Figure 2 The structural characterization data are as follows:

[0039] 1 H NMR (600 MHz, CDCl3) δ 8.62 (d, J = 5.68 Hz, 1H), 7.43 (td, J = 7.75, 1.83 Hz, 1H), 7.34 (s, 1H), 7.32 – 7.29 (m, 2H), 7.29 – 7.26 (m, 3H), 7.10 (ddd, J = 7.52, 4.90, 1.17 Hz, 1H), 7.05 (d, J = 7.94 Hz, 1H), 3.71 (s, 3H), 1.71 (s, 6H).

[0040] 13C NMR (151 MHz, CDCl3) δ 175.7, 154.8, 149.5, 147.8, 139.8, 136.9, 135.8, 134.1, 129.4, 128.6, 127.8, 126.9, 124.0, 121.6, 52.6, 44.9, 27.5.

[0041] HRMS (ESI) m / z: [M+H] + Calcd for C 20 H 20 NO2S 338.1209; Found 338.1213.

[0042] The structure of the product obtained from the above data is deduced as shown in the following formula:

[0043]

[0044] Example 2

[0045] Sodium acetate (1.2 mmol, 4 equiv.), 3-pyridyl thiophene (0.3 mmol, 1 equiv.), [Ru(p-cymene)Cl2]2(0.015 mmol, 5 mol%), ethyl 2-bromoisobutyrate (1.2 equiv.) and chlorobenzene (1 mL) were added successively into a 15 mL oven-dried Schlenk tube. The reaction mixture was stirred at 130 °C for 16 hours under an argon atmosphere. After cooling to room temperature and concentration, the crude mixture was purified by silica gel column chromatography (PE:EA = 9:1) to obtain the desired product.

[0046] The hydrogen spectrum and carbon spectrum of the product obtained are shown in Figure 3 and Figure 4 respectively, and the structure characterization data are as follows:

[0047] 1H NMR (600 MHz, CDCl3) δ 8.62 (d, J = 5.66 Hz, 1H), 7.42 (td, J =7.75, 1.83 Hz, 1H), 7.35 (s, 1H), 7.32 – 7.29 (m, 2H),7.29 – 7.26 (m, 3H),7.10 (ddd, J = 7.46, 4.89, 1.03 Hz, 1H), 7.06 (d, J = 7.94 Hz, 1H), 4.17 (q,J = 7.12 Hz, 2H), 1.71 (s, 6H), 1.26 (t, J = 7.12 Hz, 3H).

[0048] 13 C NMR (151 MHz, CDCl3) δ 175.2, 154.8, 149.5, 148.0, 139.8, 136.8,135.8, 134.2, 129.4, 128.6, 127.8, 126.8, 124.0, 121.5, 61.3, 44.9, 27.5,14.1.

[0049] HRMS (ESI) m / z: [M+H] + Calcd for C 21 H 22 NO2S 352.1366; Found 352.1371.

[0050] The structure of the product obtained from the above data is deduced as shown in the following formula:

[0051]

[0052] Example 3

[0053] Sodium acetate (1.2 mmol, 4 equiv.), 3-pyridylthiophene (0.3 mmol, 1 equiv.), [Ru(p-cymene)Cl2]2(0.015 mmol, 5 mol%), tert-butyl 2-bromoisobutyrate (1.2 equiv.) and chlorobenzene (1 mL) were added successively into a 15 mL oven-dried Schlenk tube. The reaction mixture was stirred at 130 °C for 16 hours under an argon atmosphere. After cooling to room temperature and concentration, the crude mixture was purified by silica gel column chromatography (PE:EA = 9:1) to give the desired product.

[0054] The hydrogen spectrum and carbon spectrum of the product obtained areFigure 5 and Figure 6 The structure characterization data are as follows:

[0055] 1 H NMR (600 MHz, CDCl3) δ 8.64 (d, J = 5.59 Hz, 1H), 7.45 (td, J =7.74, 1.82 Hz, 1H), 7.35 – 7.32 (m, 3H), 7.31 – 7.28 (m, 3H), 7.12 (ddd, J =7.48, 4.92, 1.17 Hz, 1H), 7.09 (d, J = 7.94 Hz, 1H), 1.69 (s, 6H), 1.48 (s,9H).

[0056] 13 C NMR (151 MHz, CDCl3) δ 174.2, 155.0, 149.5, 148.4, 139.8, 136.6,135.8, 134.3, 129.4, 128.5, 127.7, 126.5, 124.0, 121.5, 81.1, 45.7, 27.9,27.6.

[0057] HRMS (ESI) m / z: [M+H] + Calcd for C 23 H 26 NO2S 380.1679; Found 380.1684.

[0058] The structure of the product obtained according to the above data is as follows:

[0059]

[0060] Example 4

[0061] Sodium acetate (1.2 mmol, 4 equiv.), 3-pyridylthiophene (0.3 mmol, 1 equiv.), [Ru(p-cymene)Cl2]2(0.015 mmol, 5 mol%), isopropyl 2-bromoisobutyrate (1.2 equiv.) and chlorobenzene (1 mL) were added successively into a 15 mL oven-dried Schlenk tube. The reaction mixture was stirred at 130 °C for 16 hours under an argon atmosphere. After cooling to room temperature and concentration, the crude mixture was purified by silica gel column chromatography (PE:EA = 9:1) to give the desired product.

[0062] The hydrogen spectrum and carbon spectrum of the obtained product are shown in Figure 7 and Figure 8 The structural characterization data are as follows:

[0063] 1 H NMR (600 MHz, CDCl3) δ 8.62 (d, J = 5.49 Hz, 1H), 7.43 (td, J =7.73, 1.82 Hz, 1H), 7.34 (s, 1H), 7.32 – 7.29 (m, 2H), 7.28 – 7.26 (m, 3H),7.10 (ddd, J = 7.51, 4.87, 1.16 Hz, 1H), 7.06 (d, J = 7.95 Hz, 1H), 5.02(hept, J = 6.24 Hz, 1H), 1.69 (s, 6H), 1.24 (d, J = 6.28 Hz, 6H).

[0064] 13 C NMR (151 MHz, CDCl3) δ 174.6, 154.9, 149.5, 148.1, 139.8, 136.7,135.8, 134.2, 129.4, 128.5, 127.7, 126.7, 124.0, 121.5, 68.7, 45.0, 27.5,21.6.

[0065] HRMS (ESI) m / z: [M+H] + Calcd for C 22 H 24 NO2S 366.1522; Found 366.1528.

[0066] According to the above data, the structure of the obtained product is as follows:

[0067]

[0068] Example 5 Sodium acetate (1.2 mmol, 4 equiv.), 3-pyridyl thiophene (0.3 mmol, 1 equiv.), [Ru(p-cymene)Cl2]2(0.015 mmol, 5 mol%), phenyl 2-bromo-2-methylpropanoate (1.2 equiv.) and chlorobenzene (1 mL) were added successively into a 15 mL oven-dried Schlenk tube. The reaction mixture was stirred at 130 °C for 16 hours under an argon atmosphere. After cooling to room temperature and concentration, the crude mixture was purified by silica gel column chromatography (PE:EA = 9:1) to give the desired product.

[0069] The1H NMR and13C NMR spectra of the product obtained are shown in Figure 9 and Figure 10 The structural characterization data are as follows:

[0070] 1 H NMR (600 MHz, CDCl3) δ 8.65 (d, J = 4.16 Hz, 1H), 7.50 (s, 1H),7.45 (td, J = 7.75, 1.74 Hz, 1H), 7.37 – 7.34 (m, 4H), 7.32 – 7.29 (m, 3H),7.21 (t, J = 7.43 Hz, 1H), 7.13 – 7.08 (m, 4H), 1.88 (s, 6H).

[0071] 13 C NMR (151 MHz, CDCl3) δ 173.7, 154.7, 151.0, 149.6, 147.1, 140.2,137.1, 135.9, 134.1, 129.4, 129.4, 128.7, 128.6, 127.9, 127.2, 125.8, 124.0,121.7, 121.4, 45.3, 27.5.

[0072] HRMS (ESI) m / z: [M+H] + Calcd for C 25 H 22 NO2S 400.1366; Found 400.1369.

[0073] The structure of the product obtained is inferred from the above data as shown in the following formula:

[0074]

[0075] Example 6 Sodium acetate (1.2 mmol, 4 equiv.), 3-pyridylthiophene (0.3 mmol, 1 equiv.), [Ru(p-cymene)Cl2]2(0.015 mmol, 5 mol%), 3-bromo-3-methyl-2-butanone (1.2 equiv.) and chlorobenzene (1 mL) were added successively into a 15 mL oven-dried Schlenk tube. The reaction mixture was stirred at 130 °C for 16 hours under an argon atmosphere. After cooling to room temperature and concentration, the crude mixture was purified by silica gel column chromatography (PE:EA = 9:1) to give the desired product.

[0076] The hydrogen spectrum and carbon spectrum of the obtained product are shown in Figure 11 and Figure 12 The structural characterization data are as follows:

[0077] 1 H NMR (600 MHz, CDCl3) δ 8.63 (d, J = 4.32 Hz, 1H), 7.44 (td, J = 7.73, 1.85 Hz, 1H), 7.33 (s, 1H), 7.32 – 7.27 (m, 5H), 7.14 – 7.10 (m, 1H), 7.07 (dt, J = 7.93, 1.05 Hz, 1H), 2.16 (s, 3H), 1.61 (s, 6H).

[0078] 13 C NMR (151 MHz, CDCl3) δ 209.3, 154.6, 149.6, 147.7, 140.2, 137.4, 135.9, 133.9, 129.4, 128.6, 127.9, 127.2, 124.0, 121.7, 50.7, 26.1, 25.2.

[0079] HRMS (ESI) m / z: [M+H] + Calcd for C 20 H 20 NOS 322.1260; Found 322.1264.

[0080] The structure of the obtained product is inferred according to the above data as shown in the following formula:

[0081]

[0082] Example 7 Sodium acetate (1.2 mmol, 4 equiv.), 3-pyridylthiophene (0.3 mmol, 1 equiv.), [Ru(p-cymene)Cl2]2(0.015 mmol, 5 mol%), 2-bromo-N-isopropyl-2-methylpropanamide (1.2 equiv.) and chlorobenzene (1 mL) were added successively into a 15 mL oven-dried Schlenk tube. The reaction mixture was stirred at 130 °C for 16 hours under an argon atmosphere. After cooling to room temperature and concentration, the crude mixture was purified by silica gel column chromatography (PE:EA = 9:1) to give the desired product.

[0083] The1H NMR and13C NMR spectra of the product obtained are shown in Figure 13 and Figure 14 The structural characterization data are as follows:

[0084] 1 H NMR (600 MHz, CDCl3) δ 8.61 (d, J = 4.22 Hz, 1H), 7.44 (td, J =7.75, 1.77 Hz, 1H), 7.36 (s, 1H), 7.31 – 7.26 (m, 5H), 7.13 – 7.10 (m, 1H),7.07 (d, J = 7.96 Hz, 1H), 5.52 (d, J = 7.31 Hz, 1H), 4.07 – 3.98 (m, 1H),1.66 (s, 6H), 1.07 (d, J = 6.59 Hz, 6H).

[0085] 13 C NMR (151 MHz, CDCl3) δ 174.7, 154.6, 149.6, 148.9, 140.7, 136.9,135.9, 133.9, 129.3, 128.6, 128.0, 127.4, 124.1, 121.8, 45.6, 41.7, 28.1,22.5.

[0086] HRMS (ESI) m / z: [M+H] + Calcd for C 22 H 25 N2OS 365.1682; Found 365.1687.

[0087] The structure of the product obtained is inferred from the above data as shown in the following formula:

[0088] The structure of the product obtained is inferred from the above data as shown in the following formula:

[0089] Example 8

[0090] Sodium acetate (1.2 mmol, 4 equiv.), 3-pyridyl thiophene (0.3 mmol, 1 equiv.), [Ru(p-cymene)Cl2]2(0.015 mmol, 5 mol%), benzyl 2-bromoisobutyrate (1.2 equiv.) and chlorobenzene (1 mL) were added sequentially into a 15 mL oven-dried Schlenk tube. The reaction mixture was stirred at 130 °C for 16 hours under an argon atmosphere. After cooling to room temperature and concentration, the crude mixture was purified by silica gel column chromatography (PE:EA = 9:1) to give the desired product.

[0091] The1H NMR and13C NMR spectra of the product obtained are shown in Figure 15 and Figure 16 The structural characterization data are as follows:

[0092] 1 H NMR (600 MHz, CDCl3) δ 8.64 (d, J = 5.45 Hz, 1H), 7.44 (td, J =7.71, 1.84 Hz, 1H), 7.38 (s, 1H), 7.32 – 7.31 (m, 5H), 7.31 – 7.28 (m, 4H),7.22 – 7.19 (m, 1H), 7.13 – 7.10 (m, 1H), 7.06 (d, J = 7.95 Hz, 1H), 5.18 (s,2H), 1.75 (s, 6H).

[0093] 13 C NMR (151 MHz, CDCl3) δ 174.9, 154.8, 149.5, 147.7, 139.9, 137.0,136.0, 135.8, 134.2, 129.4, 128.6, 128.5, 128.0, 127.8, 127.8, 127.0, 124.0,121.6, 66.9, 45.1, 27.4.

[0094] HRMS (ESI) m / z: [M+H] + Calcd for C 26 H 24 NO2S 414.1522; Found 414.1526.

[0095] The structure of the product obtained from the above data is deduced as shown in the following formula:

[0096]

Claims

1. A method for synthesizing 2-aryl-5-alkyl-3-pyridylthiophene, characterized in that: 2-aryl-5-alkyl-3-pyridinylthiophene was prepared by a one-pot three-component reaction using 3-pyridinylthiophene, bromoalkanes and chlorobenzene as raw materials and ruthenium catalyst.

2. The synthesis method according to claim 1, characterized in that: Compound 1, Compound 2, Compound 3, ruthenium catalyst, base and solvent were added to the reactor and stirred under an argon atmosphere. After the reaction was completed, the mixture was cooled to room temperature and concentrated. The crude mixture was then purified by silica gel column chromatography to obtain 2-aryl-5-alkyl-3-pyridinylthiophene. Among them, Compound 1 is a 3-pyridinylthiophene compound, Compound 2 is a bromoalkane, and Compound 3 is chlorobenzene.

3. The synthesis method according to claim 2, characterized in that... The reaction conforms to the following reaction formula: 。 4. The synthesis method according to claim 2, characterized in that: The ruthenium catalyst is one or more of the following: dichloro(pentamethylcyclopentadienyl)ruthenium polymer, triphenylphosphine ruthenium chloride, tri(acetylacetonate)ruthenium, dichlorodicarbonylbis(triphenylphosphine)ruthenium, ruthenium trichloride hydrate, and dichlorobis(4-methylisopropylphenyl)ruthenium; the base is sodium carbonate, potassium dihydrogen phosphate, potassium benzoate, lithium acetate, potassium pivalate, potassium phosphate, sodium bicarbonate, sodium trifluoroacetate, potassium acetate, and disodium hydrogen phosphate. The solvent is one or more of the following: lithium carbonate, sodium p-toluenesulfonate, cesium carbonate, cesium acetate, potassium trifluoroacetate, sodium phosphate, sodium benzenesulfonate, sodium dihydrogen phosphate, sodium acetate, and lithium trifluoroacetate; the solvent is one or more of the following: hexafluoroisopropanol, tetrahydrofuran, toluene, ethanol, dimethyl sulfoxide, 1,2-dichloroethane, trifluorotoluene, tert-butanol, chlorobenzene, 1,4-dioxane, acetonitrile, isopropanol, methanol, and dichloromethane.

5. The synthesis method according to claim 4, characterized in that: The ruthenium catalyst is dichlorobis(4-methylisopropylphenyl)ruthenium, the base is sodium acetate, and the solvent is chlorobenzene.

6. The synthesis method according to claim 2, characterized in that: The molar ratio of compound 1 to compound 2 is 1:1 to 6.

7. The synthesis method according to claim 6, characterized in that: The reaction temperature is 0–150 °C, and the reaction time is 0–48 h.

8. The synthesis method according to claim 7, characterized in that: The molar ratio of compound 1 to compound 2 is 1:1.2, the reaction temperature is 130 °C, and the reaction time is 16 h.

9. The synthesis method according to claim 2, characterized in that: The reactor is a Schlenk tube.

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