Phosphine compound and preparation method thereof, and preparation method of catalyst
The preparation of cyano or cyanoethyl phosphine compounds through direct reaction and forming a catalyst with transition metal ions and rhodium compounds is solved, and the complex phosphine ligand synthesis route is achieved, achieving efficient catalytic olefin hydroformylation and easy recovery of catalysts.
Patent Information
- Application Number
- CN202311849867.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-29
- Publication Date
- 2025-07-01
AI Technical Summary
The synthesis route of existing phosphine ligands is complex and cumbersome, and it is difficult to meet the needs of efficient catalytic olefin hydroformylation reactions.
By mixing compound A, alkali and phosphorus trihalide under an inert atmosphere, followed by a warming reaction, a phosphine compound with a cyano group or a cyanoethyl group was prepared and reacted with a transition metal ion and a rhodium-containing compound to form a catalyst.
The synthesis route is simplified, the activity and selectivity of phosphine compounds are improved, and the hydroformylation reaction of olefins can be catalyzed at low temperatures, and the catalyst is easy to recover and recycle.
Smart Images
Figure CN120230144A_ABST
Abstract
Description
Technical Field
[0001] This application relates to organic synthesis, and particularly to the synthesis of phosphine. Background Art
[0002] When catalyzing the hydroformylation reaction of olefins, the rhodium catalyst with a phosphine ligand containing an electron-withdrawing substituent has much higher catalytic activity than the ligand without an electron-withdrawing substituent, and the selectivity is improved. At the same time, as the number of electron-withdrawing groups in the substituent increases, both the linear aldehyde selectivity and the catalytic activity increase significantly. Therefore, the method for synthesizing phosphine ligands with electron-withdrawing groups has received extensive attention. However, among the reported electron-withdrawing phosphine ligands, most of them introduce electron-withdrawing groups such as -F and -CF3. Although the introduction of these groups significantly improves the catalytic activity of the hydroformylation reaction, their synthetic routes are complex and cumbersome. Summary of the Invention
[0003] Embodiments of this application provide a phosphine compound, a preparation method thereof, and a preparation method of a catalyst to solve the technical problem that the synthetic route of the existing phosphine ligand is complex and cumbersome.
[0004] In a first aspect, embodiments of this application provide a preparation method of a phosphine compound. The preparation method of the phosphine compound includes the following steps:
[0005] Mix compound A, a base, phosphorus trihalide, and an organic solvent under a first temperature and an inert gas atmosphere to obtain a mixture;
[0006] Heat the mixture to a second temperature and react for a predetermined time to obtain the phosphine compound.
[0007] Wherein, compound A is one of the molecules represented by the following general formula:
[0008] The number of group X is 1 to 6, group X is connected to any one of the 2nd, 3rd, 4th, 5th, 6th, and 7th positions of indole, and group X is a cyano group or a cyanoethyl group.
[0009] In some embodiments of this application, the molar ratio of compound A to the base is 1:0.5 to 2.
[0010] In some embodiments of this application, the molar ratio of phosphorus trihalide to compound A is 1:3 to 4.
[0011] In some embodiments of this application, the base is at least one of KOH, DMAP, NEt3, NaH, and DIPA.
[0012] In some embodiments of this application, the organic solvent is at least one of toluene, n-hexane, diethyl ether, and tetrahydrofuran.
[0013] In some embodiments of the present application, the first temperature is -20 to 5 °C.
[0014] In some embodiments of the present application, the second temperature is 25 to 60 °C.
[0015] In some embodiments of the present application, the predetermined time is 6 to 12 h.
[0016] In a second aspect, an embodiment of the present application provides a phosphine compound, which is a phosphine compound prepared by the method according to any one of the embodiments of the first aspect.
[0017] In a third aspect, an embodiment of the present application provides a method for preparing a catalyst, the method for preparing the catalyst comprising the following steps:
[0018] Reacting the phosphine compound with a transition metal ion to form a complex;
[0019] Reacting the complex with a rhodium-containing compound to form the catalyst.
[0020] In some embodiments of the present application, the transition metal ion is Cu 2+ , Zn 2+ , Ag + , Fe 3+ or at least one of them; and / or,
[0021] The rhodium-containing compound is at least one of rhodium trihalide and rhodium dicarbonyl acetylacetonate.
[0022] The above technical solutions provided by the embodiments of the present application have the following advantages compared with the prior art:
[0023] The method for preparing a phosphine compound provided by the embodiment of the present application can directly react compound A with phosphorus trihalide to obtain a phosphine compound, and the synthesis route is simple and the process is easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.
[0025] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.
[0026] Figure 1Schematic flow chart of a method for preparing a phosphine compound provided by an embodiment of the present application. Detailed implementation manners
[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the scope of protection of the present application.
[0028] Unless otherwise specifically stated, the terms used herein should be understood as having the meanings as commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meaning as the general understanding of those skilled in the art to which the present application belongs. In case of conflict, this specification shall prevail.
[0029] Unless otherwise specifically stated, various raw materials, reagents, instruments, and equipment used in the present application can be obtained through market purchases or can be prepared by existing methods.
[0030] The existing synthesis routes of phosphine ligands have complex and cumbersome technical problems.
[0031] The technical solution provided by the embodiment of the present application is to solve the above technical problems, and the general idea is as follows:
[0032] First, an embodiment of the present application provides a method for preparing a phosphine compound. Please refer to Figure 1 , and the method for preparing the phosphine compound includes the following steps:
[0033] S11: Mix compound A, a base, phosphorus trihalide, and an organic solvent under a first temperature and an inert gas atmosphere to obtain a mixture;
[0034] S12: Heat the mixture to a second temperature and react for a predetermined time to obtain the phosphine compound.
[0035] Among them, compound A is one of the molecules represented by the following general formula:
[0036] The number of group X is 1 to 6, group X is connected to any one of the 2nd, 3rd, 4th, 5th, 6th, and 7th positions of indole, and group X is a cyano group or a cyanoethyl group.
[0037] As an example, when group X is a cyano group, the reaction equation is as follows:
[0038]
[0039] In this application, by directly reacting compound A with phosphorus trihalide, a phosphine compound can be obtained. The synthetic route is simple and the process is easy to operate.
[0040] In addition, the phosphine compound prepared by the method described in this application has high activity. After binding with rhodium, it can catalyze the hydroformylation reaction of olefins at low temperature and has good linear aldehyde selectivity.
[0041] The phosphine compound prepared by the method described in this application has multiple cyano groups or cyanoethyl groups, and can be coordinated with transition metal ions and assembled into a supramolecular coordination polymer, which is beneficial to the recovery and recycling of the catalyst.
[0042] In some embodiments of this application, the molar ratio of compound A to the base is 1:0.5 to 2.
[0043] In this application, the base acts as a catalyst, and a sufficient amount is sufficient.
[0044] As an example, the molar ratio of compound A to the base can be 1:0.5, 1:1, 1:1.5, 1:2.
[0045] In some embodiments of this application, the molar ratio of phosphorus trihalide to compound A is 1:3 to 4.
[0046] The beneficial effect of the molar ratio of phosphorus trihalide to compound A being 1:3 to 4 is to ensure that compound A is sufficient or in excess.
[0047] In some embodiments of this application, the base is at least one of KOH, DMAP, NEt3, NaH, and DIPA.
[0048] Those skilled in the art can select one of the above bases according to the acidity of the N-H bond in the indole ring.
[0049] In some embodiments of this application, the organic solvent is at least one of toluene, n-hexane, ether, and tetrahydrofuran.
[0050] The above solvents do not react with the reactants and products, have good solubility for the reactants and products, and have a low boiling point, making it easy to separate from the products.
[0051] In some embodiments of this application, the first temperature is -20 to 5 °C.
[0052] Phosphorus trichloride is unstable, and low temperature should be maintained during the mixing step.
[0053] As an example, the first temperature can be -20 °C, -15 °C, -10 °C, 0 °C, 5 °C.
[0054] In some embodiments of the present application, the second temperature is 25 to 60 °C.
[0055] The reaction rate of phosphorus trihalide and compound A is very fast, and they can react rapidly at 25 to 60 °C. Too high a temperature may cause the solvent to boil.
[0056] As an example, the second temperature can be 25 °C, 35 °C, 45 °C, 55 °C, 60 °C.
[0057] In some embodiments of the present application, the predetermined time is 6 to 12 h.
[0058] The reaction rate of phosphorus trihalide and compound A is affected by temperature, and they can usually react completely within 6 to 12 h.
[0059] As an example, the predetermined time can be 6 h, 8 h, 9 h, 10 h, 12 h.
[0060] In a second aspect, embodiments of the present application provide a phosphine compound, which is a phosphine compound prepared by the method according to any one of the embodiments of the first aspect.
[0061] As an example, the phosphine compound can be any one selected from the following compounds:
[0062]
[0063] In a third aspect, embodiments of the present application provide a method for preparing a catalyst, and the method for preparing the catalyst includes the following steps:
[0064] S21: Reacting the phosphine compound with a transition metal ion to form a complex;
[0065] S22: Reacting the complex with a rhodium-containing compound to form the catalyst.
[0066] Currently, the hydroformylation reaction of olefins usually uses a complex formed by reacting a phosphine compound with rhodium as a catalyst. This catalyst usually exists in a dissolved state in solution and is not easily recovered after catalysis.
[0067] The phosphine compound provided by the present application, its cyano or cyanoethyl group can form a complex with a transition metal ion, and the lone pair electrons of its phosphorus atom have a specific binding ability with rhodium, which enables the phosphine compound to combine with the transition metal ion and rhodium to form a supramolecular coordination polymer, that is, the catalyst. The supramolecular coordination polymer is usually solid and can be collected by conventional solid-liquid separation means, such as filtration, centrifugation, etc.
[0068] In some embodiments of the present application, the transition metal ion is Cu 2+ 、Zn2+ 、Ag + 、Fe 3+ at least one of; and / or,
[0069] The rhodium-containing compound is at least one of rhodium trihalide and rhodium dicarbonyl acetylacetonate.
[0070] The present application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present application and not to limit the scope of the present application. The experimental methods without specific conditions noted in the following embodiments are generally determined according to industry standards. If there is no corresponding industry standard, they are carried out according to general international standards, conventional conditions, or conditions recommended by the manufacturer.
[0071] Example 1
[0072] In this example, a method for tricyano(4-cyanoindolyl)phosphine ligand compound is provided, and the structural formula is as shown in I-a.
[0073]
[0074] The preparation steps are as follows: Weigh 4-cyanoindole (18.2 mmol) and 0.87 g of KOH into a three-necked flask. Replace the gas in the three-necked flask with argon three times, and then add 20 mL of THF. React at room temperature for 5 h. Subsequently, add phosphorus trichloride (5.5 mmol) to the three-necked flask under ice bath stirring. After the addition is complete, continue stirring under ice bath conditions for 20 min, warm up to 25 °C and react for 20 min, and finally react at 40 °C for 6 h. After the reaction is completed, let it stand and cool to 25 °C. Filter the product through a needle filter to remove inorganic salts. Use a solution obtained by mixing dichloromethane and ethyl acetate in a volume ratio of 10:1 as the mobile phase, and separate the tricyano(4-cyanoindolyl)phosphine ligand compound solution by column chromatography. After removing the solvent, the yield is 83%. The nuclear magnetic resonance structural characterization of the product I-a is as follows: 31 P NMR (162 MHz, CDCl3) δ 65.29. 1 H NMR (400 MHz, CDCl3) δ 8.04 (q, J = 1.2 Hz, 3H), 7.61 (dq, J = 8.6, 1.0 Hz, 3H), 7.53 (dd, J = 8.6, 1.6 Hz, 3H), 7.05 (dd, J = 3.5, 2.6 Hz, 3H), 6.88 (dt, J = 3.6, 0.8 Hz, 3H).
[0075] Example 2
[0076] In this example, a method for tricyano(5-cyanoindolyl)phosphine ligand compound is provided, and the structural formula is as shown in I-b.
[0077]
[0078] The preparation steps are as follows: Weigh 5-cyanoindole (18.2 mmol) into a constant pressure dropping funnel. Replace the gas in the three-necked flask with argon three times. Then add 20 mL of toluene and 8 mL of triethylamine to the constant pressure dropping funnel. Add 10 mL of toluene to the three-necked flask, cool it in an ice bath, and add phosphorus trichloride (5.5 mmol) to the three-necked flask under stirring. Dropwise add 5-cyanoindole (white flocculent substances are produced). After the dropping is completed, continue to stir for 20 min in the ice bath, raise the temperature to 25 °C and react for 20 min, and finally react at 30 °C for 12 h. After the reaction is completed, let it stand and cool to 25 °C. Filter the product through a needle filter to remove triethylamine hydrochloride. Use a solution prepared by mixing petroleum ether and dichloromethane in a volume ratio of 10:1 as the mobile phase, and separate the tris-(4-cyanoindolyl)phosphine ligand compound solution by column chromatography. After removing the solvent, the yield is 60%.
[0079] Perform nuclear magnetic resonance structural characterization on product I-b, and the results are as follows: 31 P NMR (162 MHz, CDCl3) δ 66.53. 1 HNMR (400 MHz, CDCl3) δ 8.05 (dt, J = 1.8, 0.9 Hz, 3H), 7.61 (dq, J = 8.7, 0.9 Hz, 3H), 7.54 (dd, J = 8.6, 1.6 Hz, 3H), 7.05 (dd, J = 3.5, 2.6 Hz, 3H), 6.88 (dt, J = 3.5, 0.8 Hz, 3H).
[0080] Example 3
[0081] In this example, a method for tris-(6-cyanoindolyl)phosphine ligand compound is provided, and the structural formula is as I-c.
[0082]
[0083] The preparation steps are as follows: Weigh 6-cyanoindole (18.2 mmol) and 0.5 g of sodium hydride into a three-necked flask. Replace the gas in the three-necked flask with argon three times. Then add 20 mL of diethyl ether and react at room temperature for 5 h. Subsequently, cool it in an ice bath, and add phosphorus trichloride (5.5 mmol) to the three-necked flask under stirring. After the dropping is completed, continue to stir for 20 min, raise the temperature to 25 °C and react for 20 min, and finally react at 25 °C for 8 h. After the reaction is completed, let it stand and cool to 25 °C. Filter the product through a needle filter to remove inorganic salts. Use dichloromethane as the mobile phase, and separate the tris-(4-cyanoindolyl)phosphine ligand compound solution by column chromatography. After removing the solvent, the yield is 83%. Perform nuclear magnetic resonance structural characterization on product I-c, and the results are as follows: 31P NMR (162 MHz, CDCl3) δ 68.36. 1 H NMR (400 MHz, CDCl3) δ 7.85 - 7.78 (m, 6H), 7.55 (dd, J=8.2, 1.3 Hz, 3H), 7.12 (t, J=3.2 Hz, 3H), 6.89 (dt, J=3.4, 0.8 Hz, 3H).
[0084] Example 4
[0085] In this example, a method for preparing tris-(3-cyanoethylindolyl)phosphine ligand compound is provided, and the structural formula is as shown in I-d.
[0086]
[0087] The preparation steps are as follows: Weigh 3-cyanoethylindole (18.2 mmol) into a constant pressure dropping funnel. Replace the gas in the three-necked flask with nitrogen three times. Then add 20 mL of n-hexane and 5 mL of DMAP to the constant pressure dropping funnel. Add 10 mL of n-hexane to the three-necked flask, cool it in an ice bath, and add phosphorus trichloride (5.5 mmol) to the three-necked flask under stirring. Dropwise add 5-cyanoindole (white flocculent substances are produced). After the addition is complete, continue to stir for 20 min in an ice bath, raise the temperature to 25 °C and react for 20 min, and finally react at 60 °C for 10 h. After the reaction is completed, let it stand and cool to 25 °C. Filter the product through a needle filter to remove DMAP hydrochloride. Use a solution obtained by mixing dichloromethane and petroleum ether in a volume ratio of 1:5 as the mobile phase, and separate the tris-(4-cyanoindolyl)phosphine ligand compound solution by column chromatography. After removing the solvent, the yield is 72%. The nuclear magnetic resonance structural characterization of the product I-d is as follows: 31 P NMR (162 MHz, CDCl3) δ 66.52. 1 H NMR (400 MHz, CDCl3) δ 7.72 - 7.66 (m, 3H), 7.58 - 7.53 (m, 3H), 7.38 - 7.32 (m, 6H), 7.01 (dt, J=2.5, 1.2 Hz, 3H), 3.81 (d, J=1.1 Hz, 6H).
[0088] Example 5
[0089] This example provides a preparation method of a catalyst, which is as follows:
[0090] Weigh tris-(4-cyanoindolyl)phosphine ligand (0.2 mmol) into a dropping funnel under constant pressure. Replace the gas in the three-necked flask with nitrogen three times. Then add 20 mL of acetonitrile to the dropping funnel under constant pressure. Add 0.15 mmol of copper perchlorate and 10 mL of ethanol to the three-necked flask. While stirring at room temperature, drop the tris-(4-cyanoindolyl)phosphine ligand into the copper perchlorate solution. White flocculent substances are produced. After dropping, raise the temperature to 60 °C and react for 10 h. After the reaction is completed, let it stand and cool to 25 °C. Drop an ethanol solution of 0.2 mmol of rhodium dicarbonylacetylacetonate into the reaction solution and stir at room temperature until the yellow solution fades. Let it stand for 1 h, then filter and collect the filter cake to obtain a yellow solid. The yield is 82%. This yellow solid is a copper-rhodium bimetallic supramolecular coordination polymer, that is, the catalyst.
[0091] The various embodiments of the present application may exist in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity and should not be construed as a rigid limitation on the scope of the present application; therefore, it should be considered that the described range description has specifically disclosed all possible sub-ranges and single values within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within that range, such as 1, 2, 3, 4, 5, and 6, and this applies regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any cited number (fraction or integer) within the indicated range.
[0092] In this application, unless otherwise specified, the orientation terms such as "upper" and "lower" specifically refer to the drawing directions in the attached drawings. Additionally, in the description of this application's specification, terms such as "include" and "comprise" mean "include but not limited to". Moreover, the term "include", "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, elements defined by the statement "comprising..." do not preclude the existence of additional identical elements in the process, method, article or device comprising said elements. In this document, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. In this document, "and / or" describes the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, or B exists alone. For the association relationship of more than three associated objects described by "and / or", it means that these three associated objects can exist alone for any one item, or any at least two of them exist simultaneously. For example, for A, and / or B, and / or C, it can represent that any one of A, B, and C exists alone, or any two of them exist simultaneously, or all three of them exist simultaneously. In this document, "at least one" means one or more, and "a plurality" means two or more. "At least one kind", "at least one of the following items (pieces)" or similar expressions refer to any combination of these items, including any combination of single item (piece) or plural items (pieces). For example, "at least one of a, b, or c", or, "at least one of a, b, and c" can both represent: a, b, c, a - b (i.e., a and b), a - c, b - c, or a - b - c, where a, b, and c can be single or multiple respectively.
[0093] The above are only specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application will not be limited to these embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features claimed herein.
Claims
1. A method for preparing a phosphine compound, characterized in that, The preparation method of the phosphine compound comprises the following steps: Mix compound A, a base, phosphorus trihalide and an organic solvent under a first temperature and an inert gas atmosphere to obtain a mixture; Heat the mixture to a second temperature and react for a predetermined time to obtain the phosphine compound, wherein the compound A is one of the molecules represented by the following general formula: The number of group X is 1 to 6, group X is connected to any one of the 2nd, 3rd, 4th, 5th, 6th, and 7th positions of indole, and group X is a cyano group or a cyanoethyl group.
2. The preparation method of the phosphine compound according to claim 1, characterized in that, The molar ratio of the compound A to the base is 1:0.5 - 2.
3. The preparation method of the phosphine compound according to claim 1, characterized in that, The molar ratio of phosphorus trihalide to the compound A is 1:3 - 4.
4. The preparation method of the phosphine compound according to claim 1, characterized in that, The base is at least one of KOH, DMAP, NEt3, NaH, DIPA.
5. The preparation method of the phosphine compound according to claim 1, characterized in that, The organic solvent is at least one of toluene, n-hexane, ether and tetrahydrofuran.
6. The method for preparing the phosphine compound according to claim 1, wherein The first temperature is -20 to 5 °C.
7. The preparation method of the phosphine compound according to claim 1, characterized in that, The second temperature is 25 to 60 °C.
8. The method for preparing the phosphine compound according to claim 1, wherein The predetermined time is 6 to 12 h.
9. A phosphine compound, characterized in that, The phosphine compound is the phosphine compound prepared by the method as described in any one of claims 1 - 8.
10. A preparation method of a catalyst, the preparation method of the catalyst comprises the following steps: React the phosphine compound with a transition metal ion to form a complex; React the complex with a rhodium-containing compound to form the catalyst.
11. The preparation method of the catalyst according to claim 10, characterized in that, The transition metal ion is Cu 2+ , Zn 2+ , Ag + , Fe 3+ or at least one of them; and / or, The rhodium-containing compound is at least one of rhodium trihalide and rhodium dicarbonyl acetylacetonate.