Rhenium complex catalyst as well as preparation method and application thereof
The preparation of rhenium complex catalysts has solved the problems of expensive precious metal catalysts and limited performance of inexpensive metal catalysts, and realized a highly efficient and environmentally friendly process for hydrogenating carbonyl derivatives to alcohols.
Patent Information
- Application Number
- CN202411378904.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-30
- Publication Date
- 2025-01-07
AI Technical Summary
Existing catalysts for the hydrogenation of carbonyl derivatives suffer from the problems of high cost of precious metals and environmental pollution, while inexpensive metal catalysts have large steric hindrance, resulting in limited catalytic performance.
Using rhenium complex catalysts, catalysts with both high reactivity and environmental friendliness are prepared by coordinating retinyl metal centers with bidentate, tridentate, or tetradentate ligands, and applied to the hydrogenation reaction of carbonyl derivative molecules.
This method achieves highly efficient catalytic hydrogenation of carbonyl derivative molecules to produce alcohols, which meets the requirements of green chemistry development and has good prospects for widespread application.
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Figure CN119264189A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of carbonyl derivative hydrogenation catalysts, in particular to a rhenium complex catalyst and a preparation method and application thereof. Background Art
[0002] Carbonyl derivatives such as aldehydes, ketones, and esters are widely present in nature and are key intermediates in many chemical processes. Catalytic hydrogenation of carbonyl derivatives to produce alcohols can effectively make up for the insufficient production of natural alcohol compounds. At present, with the development of the new energy industry, the preparation technology of "green hydrogen" has become mature. Therefore, using hydrogen as a reducing agent and developing a catalyst that can efficiently catalyze the hydrogenation of carbonyl derivative molecules to produce alcohols has become the key to the continued industrial promotion of the catalytic hydrogenation of carbonyl derivatives to produce alcohols.
[0003] At present, the catalysts that can be used to catalyze the hydrogenation of carbonyl derivative molecules mainly include two categories: supported heterogeneous catalysts and homogeneous metal complex catalysts. As we all know, supported heterogeneous catalysts often require more stringent reaction conditions, resulting in high energy consumption and high carbon emissions in the catalytic reaction process. In contrast, homogeneous metal complex catalysts have clear structural characteristics and often show excellent catalytic activity under mild reaction conditions. Compared with supported heterogeneous catalysts, they have certain advantages in the application of carbonyl derivative molecular hydrogenation.
[0004] Based on precious metals such as Ru(II) and Ir(III), researchers have successfully developed a series of complex catalysts that can efficiently catalyze the hydrogenation of carbonyl derivative molecules, and have made significant research progress. However, precious metals are expensive and will inevitably cause certain environmental pollution during use. It is well known that metals such as Fe and Mn are abundant in the earth's crust, inexpensive, and are essential trace elements for the human body. Their development and application have the advantages of low cost and environmental friendliness. Therefore, in recent years, researchers have further constructed a series of complex catalysts around cheap metals such as Mn(Ⅰ), Fe(Ⅱ) and Co(Ⅱ) and successfully applied them to the research of hydrogenation of carbonyl derivative molecules. However, Mn, Fe, Co, etc. are elements of the third period with small ionic radius. The synthesized complexes have large steric hindrance during the catalytic reaction, resulting in limited catalyst performance. Therefore, it is urgent to develop a new complex catalyst system that has the characteristics of high reaction activity and good selectivity of precious metal catalysts and environmental friendliness and low cost of cheap metals. Summary of the invention
[0005] The purpose of the present invention is to solve the problems in the prior art and to propose a rhenium complex catalyst and a preparation method and application thereof.
[0006] In order to achieve the above object, the present invention adopts the following technical solutions:
[0007] A rhenium complex catalyst includes a complex catalyst, wherein the complex catalyst is coordinated with a bidentate ligand, a tridentate ligand and a tetradentate ligand, which correspond to general formula 1, general formula 2 and general formula 3, respectively, as follows:
[0008]
[0009] The metal M is selected from Re; k, l, a, b, c, d are each independently selected from integers between 0 and 3, wherein the value range of k+l is: 0-4;
[0010] D1, D2, D3, and D4 in the general formula 1, general formula 2, and general formula 3 are donor atoms coordinated to the metal center, and are independently selected from N, P, and S;
[0011] R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 Each independently selected from hydrogen, a straight chain or branched C1-C 10 Alkyl, C3-C 10 Cycloalkyl, C4-C 24 Aryl or heteroaryl;
[0012] X and Y in the general formula 1, the general formula 2 and the general formula 3 are independently selected from CO, halogen anions, hydrogen anions, borohydride ions, hydroxide ions, sulfonate ions, nitrile ions and sulfonitrile ions.
[0013] Preferably, the interaction between M and the ligands D1, D2, D3, and D4 is a covalent bond.
[0014] Preferably, in the general formula 1, R1 and R2, R1 and R3, and R2 and R4 are connected to form C3-C 10 Cycloalkyl, C4-C 24 aryl or heteroaryl;
[0015] In the general formula 2, R1 and R3, R1 and R2, and R2 and R4 are connected to form C3-C 10 Cycloalkyl, C4-C 24 aryl or heteroaryl;
[0016] In the general formula 3, between R1 and R2, between R1 and R3, between R2 and R4, between R7 and R8, between R9 and R 11 , R9 and R 10 , R 10and R 12 Connected to C3-C 10 Cycloalkyl, C4-C 24 Aryl or heteroaryl.
[0017] A method for preparing a rhenium complex catalyst comprises the following steps:
[0018] S1. Preparation of complex catalyst: Using standard Schlenk operation technique under the condition of oxygen and water exclusion, react the ligand L and Re metal precursor in an organic solvent at a ratio of 1:0.5-2.5 for 2-100 hours in the temperature range from room temperature to reflux to obtain the complex catalyst.
[0019] Preferably, the organic solvent is one of toluene, tetrahydrofuran, 1,4-dioxane, ethanol, isopropanol, dichloromethane or diethyl ether, and the organic solvent is preferably 1,4-dioxane or toluene.
[0020] An application of a rhenium complex catalyst is applied to the catalytic hydrogenation reaction of carbonyl derivative molecules. The specific reaction steps are as follows:
[0021] S1. In an inert atmosphere glove box, weigh the metal complex catalyst, the auxiliary base, and the substrate molecule according to the molar ratio of 1:2-500:1000-1000000 and place them in a high-pressure reactor. After assembling the reactor body and transferring it out of the glove box, add 2-100 ml of solvent through a syringe under an inert atmosphere;
[0022] S2, after replacing the atmosphere in the high-pressure reactor with hydrogen, the hydrogen pressure is filled to 1-100 bar;
[0023] S3, placing the kettle in a mechanical or magnetic stirring and heating device for stirring, heating and reaction, the heating temperature is controlled within the range of room temperature 140°C, and the reaction time is 0.1 to 200 hours;
[0024] S4. After the reaction is completed, the temperature of the kettle is quickly lowered to 0-10°C and the remaining hydrogen in the kettle is discharged. The reaction liquid is filtered through a silica gel short column to obtain a hydrogenation reaction product.
[0025] Preferably, the organic solvent is one of methanol, ethanol, n-propanol, isopropanol, tert-butanol, tetrahydrofuran, 2-methyltetrahydrofuran, 1,4-dioxane or toluene, preferably isopropanol and tetrahydrofuran, and the amount used is 5 to 100 mL.
[0026] Preferably, the base is one of sodium alkoxide, potassium alkoxide, sodium hydride, potassium hydride, sodium hydroxide or potassium hydroxide, preferably sodium hydride and sodium alkoxide, and the added amount is 2 to 500 times the molar amount of the catalyst.
[0027] Compared with the prior art, the present invention has the following beneficial effects:
[0028] In view of the defects of the reported complex catalysts for catalyzing the hydrogenation of carbonyl derivative molecules, such as high price, the present invention provides a rhenium complex catalyst that has the characteristics of high reaction activity and good selectivity of precious metal catalysts and environmental friendliness and low cost of cheap metals. In addition, the preparation process of the rhenium complex catalyst is simple, and it can efficiently catalyze the hydrogenation of carbonyl derivative molecules to produce alcohols, which meets the development requirements of green chemistry and has good prospects for promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Figure 1 A rhenium complex catalyst and a preparation method thereof and a flowchart of the application of the rhenium complex catalyst in the present invention;
[0030] Figure 2 A rhenium complex catalyst and a preparation method thereof and a flow chart of the preparation method of the rhenium complex catalyst in application proposed by the present invention;
[0031] Figure 3 This is a crystal structure diagram of the catalyst in Example 8 of a rhenium complex catalyst and its preparation method and application proposed by the present invention. DETAILED DESCRIPTION
[0032] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.
[0033] Reference Figure 1-Figure 3 , a rhenium complex catalyst, including a complex catalyst, the complex catalyst is coordinated with a bidentate ligand, a tridentate ligand and a tetradentate ligand, which correspond to general formula 1, general formula 2 and general formula 3, respectively, as follows:
[0034]
[0035] The metal M is selected from Re; k, l, a, b, c, d are each independently selected from integers between 0 and 3, wherein the value range of k+l is: 0-4;
[0036] D1, D2, D3, and D4 in Formula 1, Formula 2, and Formula 3 are donor atoms coordinated to the metal center, and are independently selected from N, P, and S;
[0037] R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10, R 11 , R 12 , R 13 , R 14 , R 15 , R 16 Each independently selected from hydrogen, a straight chain or branched C1-C 10 Alkyl, C3-C 10 Cycloalkyl, C4-C 24 aryl or heteroaryl;
[0038] X and Y in Formula 1, Formula 2 and Formula 3 are independently selected from CO, halogen anion, hydrogen anion, borohydride ion, hydroxide ion, sulfonate ion, nitrile ion and sulfonitrile ion.
[0039] Furthermore, the interaction between M and the ligands D1, D2, D3, and D4 is a covalent bond or a coordination bond or no interaction, and this interaction exists both in the solid state and in solution.
[0040] Furthermore, in the general formula 1, R1 and R2, R1 and R3, and R2 and R4 are connected to form C3-C 10 Cycloalkyl, C4-C 24 aryl or heteroaryl;
[0041] In the general formula 2, R1 and R3, R1 and R2, and R2 and R4 are connected to form C3-C 10 Cycloalkyl, C4-C 24 aryl or heteroaryl;
[0042] In the general formula 3, between R1 and R2, between R1 and R3, between R2 and R4, between R7 and R8, between R9 and R 11 , R9 and R 10 , R 10 and R 12 Connected to C3-C 10 Cycloalkyl, C4-C 24 Aryl or heteroaryl.
[0043] A method for preparing a rhenium complex catalyst comprises the following steps:
[0044] S1. Preparation of complex catalyst: Using standard Schlenk operation technique under the condition of oxygen and water exclusion, react the ligand L and Re metal precursor in an organic solvent at a ratio of 1:0.5-2.5 for 2-100 hours in the temperature range from room temperature to reflux to obtain the complex catalyst.
[0045] It should be noted that: during the reaction, a white turbid solution was generated. After the reaction was completed, the reaction solution was cooled to room temperature, filtered and collected, and the generated precipitate was washed with a weak polar solvent (5 mL×3), and dried under reduced pressure to obtain a complex;
[0046] The weak polar solvent is selected from: cyclohexane, n-hexane, n-heptane, and n-pentane.
[0047] It is worth noting that the Re metal precursor is selected from ReF6, ReCl5, ReBr4, ReCl3, Re(CO)5C l, Re(CO)5Br.
[0048] It should be noted that the preparation of the metal rhenium complex catalyst was completed under the condition of oxygen and water exclusion using the standard Schlenk operation technique, the method is as follows:
[0049] In the temperature range of room temperature to 120°C, the ligand L and the metal precursor Re are reacted in an organic solvent at a ratio of 1:0.5-2.5 for 2-60 hours. After the reaction is completed, a solid precipitate is obtained by filtering, concentrating under reduced pressure, adding a weak polar solvent and other experimental steps. The obtained precipitate is collected by filtration and washed with a weak polar solvent.
[0050] Furthermore, the organic solvent is one of toluene, tetrahydrofuran, 1,4-dioxane, ethanol, isopropanol, dichloromethane or diethyl ether, and the organic solvent is preferably 1,4-dioxane or toluene.
[0051] An application of a rhenium complex catalyst is applied to the catalytic hydrogenation reaction of carbonyl derivative molecules. The specific reaction steps are as follows:
[0052] The first step is to weigh the metal complex catalyst, the auxiliary base and the substrate molecule according to the molar ratio of 1:2-500:1000-1000000 in an inert atmosphere glove box, place the metal complex catalyst, the auxiliary base and the substrate molecule in an autoclave, assemble the autoclave body and transfer it out of the glove box, and add 2-100 ml of solvent through a syringe in an inert atmosphere;
[0053] The second step is to replace the atmosphere in the autoclave with hydrogen and fill it with hydrogen to a pressure of 1 to 100 bar;
[0054] The third step is to place the kettle in a mechanical or magnetic stirring and heating device for stirring, heating and reaction, the heating temperature is controlled within the range of room temperature 140°C, and the reaction time is 0.1 to 200 hours;
[0055] Step 4: After the reaction is completed, the kettle temperature is quickly lowered to 0-10°C and the remaining hydrogen in the kettle is discharged. The reaction liquid is filtered through a silica gel short column to obtain a hydrogenation reaction product.
[0056] Furthermore, the organic solvent is one of methanol, ethanol, n-propanol, isopropanol, tert-butanol, tetrahydrofuran, 2-methyltetrahydrofuran, 1,4-dioxane or toluene, preferably isopropanol and tetrahydrofuran, and the amount used is 5 to 100 mL.
[0057] Furthermore, the base is one of sodium alcoholate, potassium alcoholate, sodium hydride, potassium hydride, sodium hydroxide or potassium hydroxide, preferably sodium hydride and sodium alcoholate, and the added amount is 2 to 500 times the molar amount of the catalyst.
[0058] Embodiment 1
[0059] Preparation of complex catalyst (Ph2PCH2CH2NH2)Re(CO)3C l:
[0060] Under an inert atmosphere, 0.18 g Re(CO)5C l (0.5 mmol) and 0.11 g ligand Ph2PCH2CH2NH2 (0.5 mmol) were weighed into a Schlenk bottle (100 mL) containing about 40 mL toluene. The bottle was sealed and heated to 100°C. After reacting for 48 hours, the generated white precipitate was collected by filtration and washed with n-hexane, and dried under reduced pressure. The yield was about 0.30 g (yield 87%).
[0061] 31 P{ 1 H} NMR (202MHz, CDCl3, 298k, ppm): δ = 30.57 (br).
[0062]
[0063] Embodiment 2
[0064] Preparation of complex catalyst (Ph2PCH2CH2NH2)2Re(CO)2C l(2):
[0065] Under an inert atmosphere, 0.18 g of Re(CO)5C l (0.5 mmol) and 0.34 g of ligand Ph2PCH2CH2NH2 (1.5 mmol) were weighed into a Schlenk bottle (100 mL) containing about 40 mL of toluene. The bottle was sealed and heated to 100°C. After reacting for 48 hours, the white precipitate was collected by filtration and washed with n-hexane, and dried under reduced pressure. The yield was about 0.15 g (yield 55%).
[0066] 31 P{ 1 H} NMR (202MHz, CDCl3, 298k, ppm): δ = -4.13 (br).
[0067]
[0068] Embodiment 3
[0069] Preparation of complex catalyst (o-Ph2PC6H4NH2)Re(CO)3C l:
[0070] Under an inert atmosphere, 0.18 g of Re(CO)5Cl (0.5 mmol) and 0.14 g of ligand o-Ph2PC6H4NH2 (0.5 mmol) were weighed into a Schlenk bottle (100 mL) containing about 50 mL of toluene, and the mixture was sealed and heated to 100° C. After reacting for 48 h, the generated white precipitate was collected by filtration and washed with n-hexane, and dried under reduced pressure, with a yield of about 0.15 g (yield 35%).
[0071] 31 P{ 1 H} NMR (202MHz, CDCl3, 298k, ppm): δ = 28.23 (br).
[0072]
[0073] Embodiment 4
[0074] Preparation of complex catalyst (o-Ph2PC6H4NH2)2Re(CO)2Cl:
[0075] Under an inert atmosphere, 0.18 g of Re(CO)5C l (0.5 mmol) and 0.42 g of ligand o-Ph2PC6H4NH2 (1.5 mmol) were weighed into a Schlenk bottle (100 mL) containing about 40 mL of toluene. The bottle was sealed and heated to 120°C. After reacting for 48 hours, the white precipitate was collected by filtration and washed with n-hexane, and dried under reduced pressure. The yield was about 0.35 g (yield 84%).
[0076] 31 P{ 1 H} NMR (202MHz, CDCl3, 298k, ppm): δ = 40.65 (br).
[0077]
[0078] Embodiment 5
[0079] Preparation of complex catalyst (o-Ph2PC6H4NHMe)Re(CO)3Cl catalyst:
[0080] Under an inert atmosphere, 0.18 g Re(CO)5 Cl (0.5 mmol) and 0.15 g ligand o-Ph2PC6H4NHMe (0.5 mmol) were weighed into a Schlenk bottle (100 mL) containing about 40 mL toluene. The bottle was sealed and heated to 100°C. After reacting for 12 h, the gray-white precipitate was collected by filtration and washed with n-hexane, and dried under reduced pressure. The yield was about 0.35 g (yield 96%).
[0081] 31 P{ 1 H} NMR (202MHz, CDCl3, 298k, ppm): δ = 28.03 (br).
[0082]
[0083] Embodiment 6
[0084] Preparation of complex catalyst [HN(CH2CH2PPh2)2]Re(CO)2Cl:
[0085] Under an inert atmosphere, 0.18 g Re(CO)5C l (0.5 mmol) and 0.22 g ligand HN(CH2CH2PPh2)2 (0.5 mmol) were weighed into a Schlenk bottle (100 mL) containing about 40 mL toluene, and the mixture was sealed and heated to 100° C. After reacting for 48 h, the generated white precipitate was collected by filtration and washed with n-hexane, and dried under reduced pressure, with a yield of about 0.30 g (yield 84%).
[0086] 31 P{ 1 H} NMR (202MHz, CDCl3, 298k, ppm): δ = 24.39 (br).
[0087]
[0088] Embodiment 7
[0089] Preparation of complex catalyst [HN(CH2CH2Pi Pr2)2]Re(CO)2Cl:
[0090] Under an inert atmosphere, 0.18 g Re(CO)5C l (0.5 mmol) and 0.15 g ligand HN(CH2CH2Pi Pr2)2 (0.5 mmol) were weighed into a Schlenk bottle (100 mL) containing about 40 mL toluene. The bottle was sealed and heated to 120°C. After reacting for 48 hours, the white precipitate was collected by filtration and washed with n-hexane, and dried under reduced pressure. The yield was about 0.18 g (yield 62%).
[0091] 31 P{ 1 H} NMR (202MHz, CDCl3, 298k, ppm): δ = 49.06 (br).
[0092]
[0093] Embodiment 8
[0094] Preparation of L6Re(CO)2C l catalyst:
[0095] Under an inert atmosphere, 0.18 g Re(CO)5Cl (0.5 mmol) and 0.30 g PNNP ligand (0.5 mmol) were weighed into a Schlenk bottle (100 mL) containing about 40 mL toluene, and the mixture was sealed and heated to 120° C. After reacting for 48 h, the generated white precipitate was collected by filtration and washed with n-hexane, and dried under reduced pressure, with a yield of about 0.36 g (yield 91%).
[0096] 31 P{ 1 H} NMR (202MHz, CDC l3, 298k, ppm): δ = 13.50 (br).
[0097]
[0098] Embodiments 9 to 30 are methods for hydrogenating aromatic ketones catalyzed by catalysts 1-8
[0099] Embodiment 9
[0100] In an argon atmosphere glove box, weigh 1.3 mg of catalyst 1, 16.5 mg of auxiliary sodium ethoxide, 0.28 mL of acetophenone (substrate ketone: sodium ethoxide: catalyst = 1000: 100: 1 (molar ratio)), and 4 mL of isopropanol into a 50 mL reactor, assemble the reactor and transfer it out of the glove box. After cooling the reactor to 5 ° C with ice water, replace the atmosphere in the reactor with hydrogen (10 bar) 3 times and fill it with hydrogen to a pressure of 20 bar. Place the reactor in a heating device and heat it to 60 ° C and maintain it at this temperature for 2 hours. After the reaction is completed, quickly reduce the temperature of the reactor to 5 ° C and drain the remaining hydrogen in the reactor. After filtering the reaction solution with a 1 cm silica gel short column, analyze it with gas chromatography (GC). The yield of the hydrogenation reaction product 1-phenylethanol is 93%.
[0101] Embodiment 10
[0102] The same experimental steps as in Example 9 were used, except that the catalyst was changed to 2 (1.8 mg), and the yield of the hydrogenation product 1-phenylethanol was 96%.
[0103] Embodiment 11
[0104] The same experimental steps as in Example 9 were used, except that the catalyst was replaced with 3 (1.4 mg), and the yield of the hydrogenation product 1-phenylethanol was 95%.
[0105] Embodiment 12
[0106] The same experimental steps as in Example 9 were used, except that the catalyst was replaced with 4 (2.0 mg). The yield of the hydrogenation product 1-phenylethanol was 97%.
[0107] Embodiment 13
[0108] The same experimental steps as in Example 9 were used, except that the catalyst was changed to 5 (1.4 mg), and the yield of the hydrogenation product 1-phenylethanol was 97%.
[0109] Embodiment 14
[0110] The same experimental steps as in Example 9 were used, except that the catalyst was replaced with 6 (1.7 mg), and the yield of the hydrogenation product 1-phenylethanol was 91%.
[0111] Embodiment 15
[0112] The same experimental steps as in Example 9 were used, except that the catalyst was replaced with 7 (1.4 mg). The yield of the hydrogenation product 1-phenylethanol was 96%.
[0113] Embodiment 16
[0114] The same experimental steps as in Example 9 were used, except that the catalyst was replaced with 8 (2.1 mg). The yield of the hydrogenation product 1-phenylethanol was 98%.
[0115] serial number catalyst Substrate:base:catalyst (molar ratio) 1-phenylethanol yield / % Embodiment 9 1 1000:100:1 93 Embodiment 10 2 1000:100:1 96 Embodiment 11 3 1000:100:1 95 Embodiment 12 4 1000:100:1 97 Embodiment 13 5 1000:100:1 97 Embodiment 14 6 1000:100:1 91 Embodiment 15 7 1000:100:1 96 Embodiment 16 8 1000:100:1 98
[0116] Table 1. Hydrogenation of acetophenone to 1-1-catalyzed by the complex catalyst in Examples 9 to 16
[0117] Phenylethanol comprehensive results
[0118] Embodiment 17
[0119] The same experimental steps as in Example 16 were used, except that the solvent was changed to tetrahydrofuran, and the yield of the hydrogenation product 1-phenylethanol was 97%.
[0120] Embodiment 18
[0121] The same experimental steps as in Example 16 were used, except that the solvent was changed to n-propanol, and the yield of the hydrogenation product 1-phenylethanol was 72%.
[0122] Embodiment 19
[0123] The same experimental steps as in Example 16 were used, except that the solvent was changed to ethanol, and the yield of the hydrogenation reaction product 1-phenylethanol was 64%.
[0124] Embodiment 20
[0125] The same experimental steps as in Example 16 were used, except that the solvent was changed to toluene, and the yield of the hydrogenation reaction product 1-phenylethanol was 22%.
[0126] Embodiment 21
[0127] The same experimental steps as in Example 16 were used, except that the auxiliary agent was replaced with sodium hydride (5.8 mg), and the yield of the hydrogenation product 1-phenylethanol was 97%.
[0128] Embodiment 22
[0129] The same experimental steps as in Example 16 were used, except that the auxiliary agent was replaced with potassium ethoxide (20.4 mg). The yield of the hydrogenation product 1-phenylethanol was 95%.
[0130] Embodiment 23
[0131] The same experimental steps as in Example 16 were used, except that the auxiliary agent was replaced with potassium hydride (9.7 mg), and the yield of the hydrogenation product 1-phenylethanol was 94%.
[0132] Embodiment 24
[0133] The same experimental steps as in Example 16 were used, except that the auxiliary agent was replaced with sodium carbonate (25.7 mg). The yield of the hydrogenation product 1-phenylethanol was 46%.
[0134] Embodiment 25
[0135] The same experimental steps as in Example 16 were used, except that the auxiliary agent was replaced with potassium carbonate (33.5 mg). The yield of the hydrogenation product 1-phenylethanol was 32%.
[0136]
[0137] Table 2. Comprehensive results of the catalytic hydrogenation of acetophenone to 1-phenylethanol by complex 8 in different solvents or with different additives in Examples 17 to 25
[0138] Embodiment 26
[0139] The same experimental steps as in Example 16 were used, except that the amount of sodium ethoxide was changed to 33.0 mg (substrate ketone: sodium ethoxide: catalyst = 1000:200:1 (molar ratio)), the reaction time was shortened to 1 h, and the yield of the hydrogenation reaction product 1-phenylethanol was 100%.
[0140] Embodiment 27
[0141] The same experimental steps as in Example 16 were used, except that the reaction temperature was lowered to 40° C. and the reaction time was extended to 6 h. The yield of the hydrogenation reaction product 1-phenylethanol was 88%.
[0142] Embodiment 28
[0143] The same experimental steps as in Example 16 were used, except that the initial hydrogen pressure was changed to 1 bar and the reaction time was extended to 8 h. The yield of the hydrogenation reaction product 1-phenylethanol was 85%.
[0144] Embodiment 29
[0145] The same experimental steps as in Example 16 were used, except that the amount of acetophenone was increased to 2.8 mL (substrate ketone: sodium ethoxide: catalyst = 10000:100:1 (molar ratio)), the amount of isopropanol was increased to 8 mL, and the reaction time was extended to 10 h. The yield of the hydrogenation reaction product 1-phenylethanol was 96%.
[0146] Embodiment 30
[0147] The same experimental steps as in Example 16 were used, except that a 100 mL reactor was used, the amount of acetophenone was increased to 14.0 mL, the amount of sodium ethoxide was changed to 33.0 mg (substrate ketone: sodium ethoxide: catalyst = 50000: 200: 1 (molar ratio)), the initial hydrogen pressure was increased to 50 bar, the reaction time was extended to 24 h, and the yield of the hydrogenation reaction product 1-phenylethanol was 97%.
[0148] Embodiment 31
[0149] The same experimental steps as in Example 30 were used, except that the amount of acetophenone was increased to 28.0 mL, the amount of sodium ethoxide was changed to 33.0 mg (substrate ketone: sodium ethoxide: catalyst = 100000: 200: 1 (molar ratio)), the reaction temperature was increased to 100° C., and the yield of the hydrogenation reaction product 1-phenylethanol was 94%.
[0150]
[0151] Table 3. Comprehensive results of the hydrogenation of acetophenone to 1-phenylethanol catalyzed by complex 8 under different conditions in Examples 26 to 31
[0152] Embodiment 32
[0153] The same experimental steps were followed as in Example 16, except that the substrate was changed to p-chloroacetophenone (0.31 mL), and the yield of the hydrogenation product 1-(4-chlorophenyl)ethanol was 97%.
[0154] Embodiment 33
[0155] The same experimental steps as in Example 16 were used, except that the substrate was changed to 4-trifluoromethylacetophenone (0.45 g), and the yield of the hydrogenation product 1-[4-(trifluoromethyl)phenyl]ethanol was 94%.
[0156] Embodiment 34
[0157] The same experimental steps were followed as in Example 16, except that the substrate was changed to 4-methylacetophenone (0.32 mL), and the yield of the hydrogenation product 1-(4-methylphenyl)ethanol was 93%.
[0158] Embodiment 35
[0159] The same experimental steps as in Example 16 were used, except that the substrate was changed to 4-methoxyacetophenone (0.36 g), and the yield of the hydrogenation product 1-(4-methoxyphenyl)ethanol was 93%.
[0160] Embodiment 36
[0161] The same experimental steps were used as in Example 16, except that the substrate was changed to p-nitroacetophenone (0.39 g), and the yield of the hydrogenation product 1-(4-nitrophenyl)ethanol was 88%.
[0162] Embodiment 37
[0163] The same experimental steps as in Example 16 were used, except that the substrate was changed to 2-methylacetophenone (0.32 g), and the yield of the hydrogenation product 1-(2-methylphenyl)ethanol was 98%.
[0164] Embodiment 38
[0165] The same experimental steps as in Example 16 were used, except that the substrate was changed to benzaldehyde (0.24 mL), and the yield of the hydrogenation product, benzyl alcohol, was 99%.
[0166] Embodiment 39
[0167] The same experimental steps were followed as in Example 16, except that the substrate was changed to furfural (0.20 mL), and the yield of the hydrogenation product furfuryl alcohol was 97%.
[0168] Embodiment 40
[0169] The same experimental steps were used as in Example 16, except that the substrate was changed to 5-hydroxymethylfurfural (0.30 g), and the yield of the hydrogenation product 2,5-furan dimethanol was 96%.
[0170] Embodiment 41
[0171] The same experimental steps were followed as in Example 16, except that the substrate was changed to myrtolide aldehyde (0.36 mL), and the yield of the hydrogenation product myrtolide alcohol was 99%.
[0172] Embodiment 42
[0173] The same experimental steps as in Example 16 were used, except that the substrate was changed to methyl benzoate (0.36 mL), and the reaction temperature was increased to 100° C. The yield of the hydrogenation product, benzyl alcohol, was 97%.
[0174] Embodiment 43
[0175] The same experimental steps were used as in Example 42, except that the substrate was changed to γ-valerolactone (0.23 mL), and the yield of the hydrogenation product 1,4-pentanediol was 99%.
[0176] Embodiment 44
[0177] The same experimental steps were used as in Example 42, except that the substrate was changed to dimethyl oxalate (0.28 g), and the yield of ethylene glycol as the hydrogenation product was 98%.
[0178] serial number Substrate Reaction temperature / ℃ Product yield / % Embodiment 32 p-Chloroacetophenone 60 97 Embodiment 33 4-Trifluoromethylacetophenone 60 94 Embodiment 34 4-Methylacetophenone 60 93 Embodiment 35 4-Methoxyacetophenone 60 93 Embodiment 36 p-Nitroacetophenone 60 88 Embodiment 37 2-Methylacetophenone 60 98 Embodiment 38 Benzaldehyde 60 99 Embodiment 39 Furfural 60 97 Embodiment 40 5-Hydroxymethylfurfural 60 96 Embodiment 41 Myrtle aldehyde 60 99 Embodiment 42 Methyl benzoate 100 97 Embodiment 43 γ-Valerolactone 100 99 Embodiment 44 Dimethyl oxalate 100 98
[0179] Table 4. Comprehensive results of the hydrogenation of different carbonyl derivative molecules catalyzed by complex 8 in Examples 32 to 44
[0180] From the experimental results in Tables 1 to 4 above, it can be seen that the rhenium complexes composed of bidentate, tridentate or tetradentate ligands invented in this patent can efficiently catalyze the hydrogenation of carbonyl derivative molecules to alcohols under appropriate conditions, showing excellent substrate applicability and functional group tolerance.
[0181] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.
Claims
1. A rhenium complex catalyst, comprising a complex catalyst, characterized in that: The complex catalyst is coordinated with a bidentate ligand, a tridentate ligand and a tetradentate ligand, which correspond to general formula 1, general formula 2 and general formula 3, respectively, as follows: The metal M is selected from Re; k, l, a, b, c, d are each independently selected from integers between 0 and 3, wherein the value range of k+l is: 0-4; D1, D2, D3, and D4 in the general formula 1, general formula 2, and general formula 3 are donor atoms coordinated to the metal center, and are independently selected from N, P, and S; R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 Each independently selected from hydrogen, a straight chain or branched C1-C 10 Alkyl, C3-C 10 Cycloalkyl, C4-C 24 aryl or heteroaryl; X and Y in the general formula 1, the general formula 2 and the general formula 3 are independently selected from CO, halogen anions, hydrogen anions, borohydride ions, hydroxide ions, sulfonate ions, nitrile ions and sulfonitrile ions.
2. A rhenium complex catalyst according to claim 1, characterized in that: The interaction between M and the ligands D1, D2, D3, and D4 is a covalent bond.
3. A rhenium complex catalyst according to claim 1, characterized in that: In the general formula 1, R1 and R2, R1 and R3, and R2 and R4 are connected to form C3-C 10 Cycloalkyl, C4-C 24 aryl or heteroaryl; In the general formula 2, R1 and R3, R1 and R2, and R2 and R4 are connected to form C3-C 10 Cycloalkyl, C4-C 24 aryl or heteroaryl; In the general formula 3, between R1 and R2, between R1 and R3, between R2 and R4, between R7 and R8, between R9 and R 11 , R9 and R 10 , R 10 and R 12 Connected to C3-C 10 Cycloalkyl, C4-C 24 Aryl or heteroaryl.
4. A method for preparing a rhenium complex catalyst according to any one of claims 1 to 3, comprising the following steps: S1. Preparation of complex catalyst: Using standard Schlenk operation technique under the condition of oxygen and water exclusion, react the ligand L and Re metal precursor in an organic solvent at a ratio of 1:0.5-2.5 for 2-100 hours in the temperature range from room temperature to reflux to obtain the complex catalyst.
5. The method for preparing a rhenium complex catalyst according to claim 4, characterized in that: The organic solvent is one of toluene, tetrahydrofuran, 1,4-dioxane, ethanol, isopropanol, dichloromethane or diethyl ether, and the organic solvent is most preferably 1,4-dioxane or toluene.
6. The use of a rhenium complex catalyst according to any one of claims 1 to 3, characterized in that: Applied to the catalytic hydrogenation reaction of carbonyl derivative molecules, the specific reaction steps are as follows: S1. In an inert atmosphere glove box, weigh the metal complex catalyst, the auxiliary base, and the substrate molecule according to the molar ratio of 1:2-500:1000-1000000 and place them in a high-pressure reactor. After assembling the reactor body and transferring it out of the glove box, add 2-100 ml of solvent through a syringe under an inert atmosphere; S2, after replacing the atmosphere in the high-pressure reactor with hydrogen, the hydrogen pressure is filled to 1-100 bar; S3, placing the kettle in a mechanical or magnetic stirring and heating device for stirring, heating and reaction, the heating temperature is controlled within the range of room temperature 140°C, and the reaction time is 0.1 to 200 hours; S4. After the reaction is completed, the temperature of the kettle is quickly lowered to 0-10°C and the remaining hydrogen in the kettle is discharged. The reaction liquid is filtered through a silica gel short column to obtain a hydrogenation reaction product.
7. The use of a rhenium complex catalyst according to claim 6, characterized in that: The organic solvent is one of methanol, ethanol, n-propanol, isopropanol, tert-butanol, tetrahydrofuran, 2-methyltetrahydrofuran, 1,4-dioxane or toluene, preferably isopropanol and tetrahydrofuran, and the amount used is 5-100 mL.
8. The use of a rhenium complex catalyst according to claim 6, characterized in that: The base is one of sodium alcoholate, potassium alcoholate, sodium hydride, potassium hydride, sodium hydroxide or potassium hydroxide, preferably sodium hydride and sodium alcoholate, and the added amount is 2 to 500 times the molar amount of the catalyst.