Preparation method of rhodium-phosphine complex catalyst and rhodium-phosphine complex catalyst
By using a one-step reaction method of bidentate phosphine ligand and hydrated rhodium trihalide in the preparation of rhodium phosphine complex catalysts, the problem of cumbersome preparation process and low yield in the prior art is solved, and efficient and simple catalyst preparation is achieved.
Patent Information
- Application Number
- CN202311806474.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-26
- Publication Date
- 2025-06-27
AI Technical Summary
In the prior art, the preparation of rhodium phosphine complexes has problems such as cumbersome process and low yield.
By providing an alcohol solution of bistodental phosphine ligand, the alcohol solution of rhodium trihalide and formaldehyde solution were added dropwise in an inert atmosphere to obtain a premixed solution, and the reaction was heated at a predetermined temperature to form a rhodium phosphine complexing catalyst.
A simple preparation process of rhodium phosphine complexing catalyst was realized, with a yield of about 95%, avoiding the problem of cumbersome processes.
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Figure CN120209039A_ABST
Abstract
Description
Technical Field
[0001] This application relates to a catalyst, and particularly to a rhodium-containing catalyst. Background Art
[0002] Oxo synthesis of olefins is an important method for preparing aldehydes and alcohols. The products are widely used in fields such as plasticizers and detergents. Usually, a rhodium-phosphine complex formed by a phosphine ligand and a rhodium precursor is used as a catalyst. During the oxo synthesis reaction of olefins, usually, the rhodium precursor and the phosphine ligand are simultaneously added to the reaction kettle, and the required catalyst is formed by in-situ generation of the rhodium-phosphine complex. In this method, the catalyst precursor and the phosphine ligand in the system cannot completely form the rhodium complex of the phosphine ligand, resulting in waste of rhodium and low catalytic reaction efficiency. At present, there are also methods recorded in the literature for directly preparing the rhodium-phosphine complex and then using it, but there are often problems such as cumbersome preparation processes and low yields. Summary of the Invention
[0003] An embodiment of this application provides a preparation method of a rhodium-phosphine complex catalyst to solve the technical problems of cumbersome preparation processes and low yields of rhodium-phosphine complexes.
[0004] In a first aspect, an embodiment of this application provides a preparation method of a rhodium-phosphine complex catalyst. The preparation method of the rhodium-phosphine complex catalyst includes the following steps:
[0005] Provide an alcohol solution of a bidentate phosphine ligand;
[0006] In an inert gas atmosphere, sequentially drop an alcohol solution of rhodium trihalide hydrate and a formaldehyde solution into the alcohol solution of the bidentate phosphine ligand to obtain a premixed solution;
[0007] Heat the premixed solution to a predetermined temperature and react for a predetermined time to obtain a rhodium-phosphine complex catalyst.
[0008] Among them, the bidentate phosphine ligand is one of the molecules represented by the general formula (1):
[0009]
[0010] Among them, R1 is selected from one of the groups represented by the general formula (2.1), the general formula (2.2), the general formula (2.3), and the general formula (2.4):
[0011]
[0012] Ar1, Ar2, Ar3, and Ar4 are all aryl groups.
[0013] In some embodiments of this application, Ar1, Ar2, Ar3, and Ar4 are each independently selected from one of the molecules represented by the general formula (3):
[0014]
[0015] Among them, R4 is a substituent.
[0016] In some embodiments of the present application, R2, R3, and R4 are each independently selected from a group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a trifluoromethyl group, a nitro group, a sulfonic acid group, or a cyano group.
[0017] In some embodiments of the present application, the rhodium trihalide hydrate is at least one of rhodium trifluoride hydrate, rhodium trichloride hydrate, rhodium tribromide hydrate, and rhodium triiodide hydrate.
[0018] In some embodiments of the present application, the solvent of the alcoholic solution of the bidentate phosphine ligand is at least one of methanol, ethanol, 1-propanol, isopropanol, 1,3-propanediol, 1-butanol, and 2-butanol.
[0019] In some embodiments of the present application, the concentration of the alcoholic solution of the bidentate phosphine ligand is 0.15 to 3.0 mol / L.
[0020] In some embodiments of the present application, the solvent of the formaldehyde solution is at least one of water and ethanol.
[0021] In some embodiments of the present application, the molar ratio of the bidentate phosphine ligand to the rhodium trihalide hydrate is 1.2 to 5.0:1.
[0022] Second, embodiments of the present application provide a rhodium-phosphorus complex catalyst, and the rhodium-phosphorus complex catalyst is one of the molecules represented by the general formula (4):
[0023]
[0024] Among them, R1 is selected from one of the groups represented by the general formula (2.1), general formula (2.2), general formula (2.3), and general formula (2.4):
[0025]
[0026] Ar1, Ar2, Ar3, and Ar4 are all aryl groups.
[0027] In some embodiments of the present application, Ar1, Ar2, Ar3, and Ar4 are each independently selected from one of the molecules represented by the general formula (3):
[0028]
[0029] Among them, R4 is a substituent.
[0030] In some embodiments of the present application, R2, R3, and R4 are each independently selected from a group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a trifluoromethyl group, a nitro group, a sulfonic acid group, or a cyano group.
[0031] The above technical solutions provided by the embodiments of the present application have the following advantages compared with the prior art:
[0032] In the method for preparing a rhodium-phosphine complex catalyst provided by the embodiments of the present application, by selecting a ligand having a bidentate phosphine structure and rhodium trihalide as reactants, a rhodium-phosphine complex catalyst can be generated through a one-step reaction, which is simple and easy to operate, without the problem of cumbersome processes, and a high yield of about 95% is achieved. BRIEF DESCRIPTION OF THE DRAWINGS
[0033] The accompanying drawings herein are incorporated into the specification and constitute a part of this specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.
[0034] In order 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 use in 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.
[0035] Figure 1 It is a schematic flow chart of a method for preparing a rhodium-phosphine complex catalyst provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, 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 of the present application without creative efforts fall within the scope of protection of the present application.
[0037] Unless otherwise specifically stated, the terms used herein should be understood as having the meaning commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meaning as generally understood by those of ordinary skill in the art to which the present application belongs. In case of conflict, this specification prevails.
[0038] Unless otherwise specifically stated, various raw materials, reagents, instruments, and equipment used in the present application can be obtained through the market or can be prepared by existing methods.
[0039] The preparation of existing rhodium-phosphine complexes has technical problems such as cumbersome processes and low yields.
[0040] The technical solutions provided in the embodiments of the present application to solve the above technical problems have the following general ideas:
[0041] In a first aspect, the embodiments of the present application provide a method for preparing a rhodium-phosphine complex catalyst. Please refer to Figure 1 , and the method for preparing the rhodium-phosphine complex catalyst includes the following steps:
[0042] S1: Provide an alcohol solution of a bidentate phosphine ligand;
[0043] S2: In an inert gas atmosphere, sequentially drop an alcohol solution of rhodium trihalide hydrate and a formaldehyde solution into the alcohol solution of the bidentate phosphine ligand to obtain a premixed solution;
[0044] S3: Heat the premixed solution to a predetermined temperature and react for a predetermined time to obtain a rhodium-phosphine complex catalyst.
[0045] Among them, the bidentate phosphine ligand is one of the molecules represented by the general formula (1):
[0046]
[0047] Among them, R1 is selected from one of the groups represented by the general formula (2.1), the general formula (2.2), the general formula (2.3), and the general formula (2.4):
[0048]
[0049] Ar1, Ar2, Ar3, and Ar4 are all aryl groups.
[0050] The beneficial effect that R1 is selected from one of the groups represented by the general formula (2.1), the general formula (2.2), the general formula (2.3), and the general formula (2.4) is that it changes the steric hindrance and electronic structure of the ligand in the catalytically active species, modulates the performance of the catalyst, and selects ligands with different structures according to the market demand for products to meet the needs of industrial production.
[0051] In the present application, by selecting a ligand with a bidentate phosphine structure and rhodium trihalide as reactants, a rhodium-phosphine complex catalyst can be generated through a one-step reaction, which is simple and easy to operate, does not have the problem of cumbersome processes, and achieves a high yield of about 95%.
[0052] In some embodiments of the present application, Ar1, Ar2, Ar3, and Ar4 are each independently selected from one of the molecules represented by the general formula (3):
[0053]
[0054] Among them, R4 is a substituent.
[0055] The beneficial effects of Ar1, Ar2, Ar3, and Ar4 being selected from the above general formula are that the generated catalyst has good activity and good selectivity.
[0056] In some embodiments of the present application, R2, R3, and R4 are each independently selected from a group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a trifluoromethyl group, a nitro group, a sulfonic acid group, or a cyano group.
[0057] When R2, R3, and R4 are selected from the above groups, it has at least one of the beneficial effects of good activity of the generated catalyst and high normal-to-iso ratio of the generated product.
[0058] In some embodiments of the present application, the hydrated rhodium trihalide is at least one of hydrated rhodium trifluoride, hydrated rhodium trichloride, hydrated rhodium tribromide, and hydrated rhodium triiodide.
[0059] In some embodiments of the present application, the solvent of the alcoholic solution of the bidentate phosphine ligand is at least one of methanol, ethanol, 1-propanol, isopropanol, 1,3-propanediol, 1-butanol, and 2-butanol.
[0060] In some embodiments of the present application, the concentration of the alcoholic solution of the bidentate phosphine ligand is 0.15 to 3.0 mol / L.
[0061] The beneficial effects of the concentration of the alcoholic solution of the bidentate phosphine ligand being selected from the above range are that it can not only fully dissolve the bidentate phosphine ligand but also ensure a high concentration of the bidentate phosphine ligand to increase the reaction rate. In addition, the reactants of the chemical reaction involved in the method of the present application are the bidentate phosphine ligand and rhodium trihalide. Increasing the concentration of the bidentate phosphine ligand is beneficial to making as much rhodium trihalide react as possible, thereby increasing the yield of the chemical reaction.
[0062] As an example, the concentration of the alcoholic solution of the bidentate phosphine ligand can be 0.15 mol / L, 0.4 mol / L, 1 mol / L, 2 mol / L, or 3.0 mol / L.
[0063] In some embodiments of the present application, the solvent of the formaldehyde solution is at least one of water and ethanol.
[0064] In some embodiments of the present application, the molar ratio of the bidentate phosphine ligand to the hydrated rhodium trihalide is 1.2 to 5.0:1.
[0065] It is easy to understand that in order to consume the relatively expensive rhodium trihalide as much as possible, the bidentate phosphine ligand should be in excess. However, when the molar ratio of the bidentate phosphine ligand to the hydrated rhodium trihalide is greater than 5.0:1, the effect of increasing the yield brought by the increase in its concentration will become very small.
[0066] In a second aspect, embodiments of the present application provide a rhodium-phosphine complex catalyst, and the rhodium-phosphine complex catalyst is one of the molecules represented by the general formula (4):
[0067]
[0068] Wherein, R1 is selected from one of the groups represented by the general formula (2.1), general formula (2.2), general formula (2.3), and general formula (2.4):
[0069]
[0070] Ar1, Ar2, Ar3, and Ar4 are all aryl groups.
[0071] In some embodiments of the present application, Ar1, Ar2, Ar3, and Ar4 are each independently selected from one of the molecules represented by the general formula (3):
[0072]
[0073] Wherein, R4 is a substituent.
[0074] In some embodiments of the present application, R2, R3, and R4 are each independently selected from one of a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a trifluoromethyl group, a nitro group, a sulfonic acid group, or a cyano group.
[0075] It is easy to understand that the rhodium-phosphine complex catalyst described in any embodiment of the second aspect of the present application can be prepared by the method described in a certain embodiment of the first aspect of the present application.
[0076] 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.
[0077] Example 1
[0078] Under nitrogen protection and reflux conditions, 1.5 g of bis(diphenylphosphino)methane (DPPM) was added to 30 mL of absolute ethanol. After complete dissolution, a solution formed by dissolving 0.5 g of hydrated RhCl3 in 10 mL of ethanol was added dropwise to the ethanol solution of the above DPPM. 2 mL of aqueous formaldehyde solution (37 wt%) was added to the ethanol solution containing rhodium and bidentate phosphine. After refluxing for 30 minutes, heating was stopped and the mixture was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried in vacuo to obtain 1.00 g of yellow RhCl(CO)(DPPM) product with a yield of 95%.
[0079] Example 2
[0080] Under nitrogen protection and reflux conditions, 1.6 g of 1,2-bis(diphenylphosphino)ethane (DPPE) was dissolved in 30 mL of absolute ethanol. After complete dissolution, a solution formed by dissolving 0.5 g of hydrated RhCl3 in 10 mL of ethanol was added dropwise to the ethanol solution of the above DPPE. 2 mL of aqueous formaldehyde solution (37 wt%) was added to the ethanol solution containing rhodium and bidentate phosphine. The solution immediately changed from reddish-brown to yellow. After refluxing for 20 minutes, heating was stopped and the mixture was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried in vacuo to obtain 1.06 g of yellow RhCl(CO)(DPPE) product with a yield of 95.0%.
[0081] Example 3
[0082] Under nitrogen protection and reflux conditions, 1.71 g of 1,4-bis(diphenylphosphino)butane (DPPB) was dissolved in 30 mL of absolute ethanol. After complete dissolution, a solution formed by dissolving 0.52 g of hydrated RhCl3 in 10 mL of ethanol was added dropwise to the ethanol solution of the above DPPB. Subsequently, 2 mL of aqueous formaldehyde solution (37 wt%) was added to the ethanol solution containing rhodium and bidentate phosphine. The solution immediately changed from reddish-brown to yellow. After refluxing for 30 minutes, heating was stopped and the mixture was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried in vacuo to obtain 1.15 g of yellow RhCl(CO)(DPPB) product with a yield of 96%.
[0083] Example 4
[0084] Under nitrogen protection and reflux conditions, 1.9 g of 1,2-bis(diphenylphosphinomethyl)benzene (DPPMB) was dissolved in 30 mL of absolute ethanol. After complete dissolution, a solution formed by dissolving 0.52 g of hydrated RhCl3 in 10 mL of ethanol was added dropwise to the above-mentioned ethanol solution of DPPMB. 15 mL of aqueous formaldehyde solution (10 wt%) was added to the above-mentioned ethanol solution containing rhodium and bidentate phosphine. The solution immediately turned from reddish-brown to yellow. After refluxing for 30 minutes, heating was stopped and the mixture was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried under vacuum to obtain 1.20 g of yellow RhCl(CO)(DPPMB) product with a yield of 94%.
[0085] Example 5
[0086] Under nitrogen protection and reflux conditions, 2.20 g of 2,2'-bis(diphenylphosphinomethyl)-1,1'-biphenyl (BISBI) was dissolved in 30 mL of absolute ethanol. After complete dissolution, a solution formed by dissolving 0.52 g of hydrated RhCl3 in 10 mL of ethanol was added dropwise to the above-mentioned ethanol solution of BISBI. Subsequently, 2 mL of aqueous formaldehyde solution (37 wt%) was added to the above-mentioned ethanol solution containing rhodium and bidentate phosphine. The solution immediately turned from reddish-brown to yellow. After refluxing for 30 minutes, heating was stopped and the mixture was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried under vacuum to obtain 1.37 g of yellow RhCl(CO)(BISBI) product with a yield of 96%.
[0087] Example 6
[0088] Under nitrogen protection, 1.59 g of 1,2-bis(diphenylphosphino)ethane (DPPE) was dissolved in 25 mL of absolute ethanol at 50 °C. After complete dissolution, while maintaining the solution temperature, a solution formed by dissolving 0.52 g of hydrated RhCl3 in 10 mL of ethanol was added dropwise to the above-mentioned ethanol solution of DPPM. Subsequently, 2 mL of aqueous formaldehyde solution (37 wt%) was added to the above-mentioned ethanol solution containing rhodium and bidentate phosphine. The solution immediately turned from reddish-brown to yellow. After stirring at this temperature for 60 minutes, heating was stopped and the mixture was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried under vacuum to obtain 1.08 g of yellow RhCl(CO)(DPPE) product with a yield of 95.6%.
[0089] Example 7
[0090] Under nitrogen protection and reflux conditions, 1.59 g of 1,2-bis(diphenylphosphino)ethane (DPPE) was dissolved in 25 mL of 95% ethanol (containing 5 wt% water). After complete dissolution, while maintaining the reflux temperature, a solution formed by dissolving 0.52 g of hydrated RhCl3 in 10 mL of 95% ethanol was added dropwise to the above-mentioned 95% ethanol solution of DPPE. Subsequently, 5 mL of aqueous formaldehyde solution (20 wt%) was added to the above-mentioned 95% ethanol solution containing rhodium and bidentate phosphine. The solution immediately changed from reddish-brown to yellow. After continuing to stir at this temperature for 60 minutes, heating was stopped, and the mixture was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried in vacuo to obtain 1.09 g of yellow RhCl(CO)(DPPE) product with a yield of 96.5%.
[0091] Example 8
[0092] Under nitrogen protection and reflux conditions, 1.59 g of 1,2-bis(diphenylphosphino)ethane (DPPE) was dissolved in 25 mL of 80% ethanol (containing 20 wt% water). After complete dissolution, while maintaining the reflux temperature, a solution formed by dissolving 0.52 g of hydrated RhCl3 in 10 mL of 80% ethanol was added dropwise to the above-mentioned 80% ethanol solution of DPPE. Subsequently, 2 mL of ethanol solution of formaldehyde (35 wt%) was added to the above-mentioned 80% ethanol solution containing rhodium and bidentate phosphine. The solution immediately changed from reddish-brown to yellow. After continuing to stir at this temperature for 60 minutes, heating was stopped, and the mixture was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried in vacuo to obtain 1.06 g of yellow RhCl(CO)(DPPE) product with a yield of 93.8%.
[0093] Example 9
[0094] Under nitrogen protection and reflux conditions, 1.59 g of 1,2-bis(diphenylphosphino)ethane (DPPE) was dissolved in 25 mL of 1-propanol. After complete dissolution, while maintaining the reflux temperature of the solution, a solution formed by dissolving 0.52 g of hydrated RhCl3 in 10 mL of ethanol was added dropwise to the above-mentioned alcohol solution of DPPM. Subsequently, 2 mL of aqueous formaldehyde solution (37 wt%) was added to the above-mentioned alcohol solution containing rhodium and bidentate phosphine. The solution immediately changed from reddish-brown to yellow. After continuing to stir at this temperature for 60 minutes, heating was stopped, and the mixture was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried in vacuo to obtain 1.05 g of yellow RhCl(CO)(DPPE) product with a yield of 92.9%.
[0095] Example 10
[0096] Under nitrogen protection and reflux conditions, 1.59 g of 1,2-bis(diphenylphosphino)ethane (DPPE) was dissolved in 25 mL of isopropanol. After complete dissolution, while maintaining the reflux temperature of the solution, a solution formed by dissolving 0.52 g of hydrated RhCl3 in 10 mL of ethanol was added dropwise to the above-mentioned alcoholic solution of DPPE. Subsequently, 2 mL of aqueous formaldehyde solution (37 wt%) was added to the above-mentioned alcoholic solution containing rhodium and bidentate phosphine. The solution immediately changed from reddish-brown to yellow. Stirring was continued at this temperature for 30 minutes, then heating was stopped and the mixture was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried under vacuum to obtain 1.08 g of yellow RhCl(CO)(DPPE) product with a yield of 95.6%.
[0097] Example 11
[0098] Under nitrogen protection and reflux conditions, 1.59 g of 1,2-bis(diphenylphosphino)ethane (DPPE) was dissolved in 25 mL of 1,3-propanediol. After complete dissolution, while maintaining the reflux temperature of the solution, a solution formed by dissolving 0.52 g of hydrated RhCl3 in 10 mL of ethanol was added dropwise to the above-mentioned alcoholic solution of DPPE. Subsequently, 2 mL of aqueous formaldehyde solution (37 wt%) was added to the above-mentioned alcoholic solution containing rhodium and bidentate phosphine. The solution immediately changed from reddish-brown to yellow. Stirring was continued at this temperature for 60 minutes and then heating was stopped. The mixture was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried under vacuum to obtain 1.09 g of yellow RhCl(CO)(DPPE) product with a yield of 96.5%.
[0099] Example 12
[0100] Under nitrogen protection and reflux conditions, 1.59 g of 1,2-bis(diphenylphosphino)ethane (DPPE) was dissolved in 25 mL of 1-hexanol. After complete dissolution, while maintaining the reflux temperature of the solution, a solution formed by dissolving 0.52 g of hydrated RhCl3 in 10 mL of ethanol was added dropwise to the above-mentioned alcoholic solution of DPPE. Subsequently, 2 mL of aqueous formaldehyde solution (37 wt%) was added to the above-mentioned alcoholic solution containing rhodium and bidentate phosphine. The solution immediately changed from reddish-brown to yellow. Stirring was continued at this temperature for 60 minutes and then heating was stopped. The mixture was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried under vacuum to obtain 1.10 g of yellow RhCl(CO)(DPPE) product with a yield of 97.3%.
[0101] Example 13
[0102] Under the conditions of nitrogen protection and reflux, 2.38 g of 1,2-bis(diphenylphosphino)ethane (DPPE) was dissolved in 40 mL of absolute ethanol. After complete dissolution, while maintaining the reflux temperature of the solution, a solution formed by dissolving 0.52 g of hydrated RhCl3 in 10 mL of ethanol was added dropwise to the above-mentioned ethanol solution of DPPE. Subsequently, 2 mL of aqueous formaldehyde solution (37 wt%) was added to the above-mentioned alcohol solution containing rhodium and bidentate phosphine. The solution immediately turned from reddish-brown to yellow. After stirring for an additional 15 minutes at this temperature, heating was stopped and the solution was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried in vacuo to obtain 1.06 g of yellow RhCl(CO)(DPPE) product with a yield of 93.8%.
[0103] Example 14
[0104] Under the conditions of nitrogen protection and reflux, 15.9 g of 1,2-bis(diphenylphosphino)ethane (DPPE) was dissolved in 150 mL of isopropanol. After complete dissolution, while maintaining the reflux temperature of the solution, a solution formed by dissolving 5.2 g of hydrated RhCl3 in 50 mL of ethanol was added dropwise to the above-mentioned isopropanol solution of DPPE. Subsequently, 10 mL of aqueous formaldehyde solution (37 wt%) was added to the above-mentioned alcohol solution containing rhodium and bidentate phosphine. The solution immediately turned from reddish-brown to yellow. After stirring for 30 minutes at this temperature, heating was stopped and the solution was cooled to precipitate a yellow solid. The obtained yellow solid was separated by filtration and washed with water and ether respectively, and then dried in vacuo to obtain 10.8 g of yellow RhCl(CO)(DPPE) product with a yield of 95.6%.
[0105] 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 description of the range has specifically disclosed all possible sub-ranges and individual values within that range. For example, it should be considered that the description of the range 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 individual numbers within the 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.
[0106] In this application, unless otherwise stated, the orientation terms such as "upper" and "lower" specifically refer to the drawing directions in the attached drawings. Additionally, in the description of the specification of this application, the terms "include", "comprise", etc. 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 also includes elements inherent to such process, method, article or device. Without further limitation, the elements defined by the statement "comprising..." do not exclude the existence of additional identical elements in the process, method, article or device comprising the said elements. In this text, 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 such actual relationship or order between these entities or operations. In this text, "and / or" describes the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can mean: 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 of them, or at least any two of them exist simultaneously. For example, for A, and / or B, and / or C, it can mean 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 text, "at least one" means one or more, and "multiple" means two or more. "At least one kind", "at least one item (piece) below" 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 item (piece) among a, b, or c", or, "at least one item (piece) among a, b, and c" can both mean: 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.
[0107] 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 preparation method of a rhodium-phosphine complex catalyst, characterized in that, The preparation method of the rhodium-phosphine complex catalyst comprises the following steps: Provide an alcohol solution of a bidentate phosphine ligand; In an inert gas atmosphere, sequentially dropwise add an alcohol solution of rhodium trihalide hydrate and a formaldehyde solution to the alcohol solution of the bidentate phosphine ligand to obtain a premixed solution; Heat the premixed solution to a predetermined temperature and react for a predetermined time to obtain a rhodium-phosphine complex catalyst. Wherein, the bidentate phosphine ligand is one of the molecules represented by the general formula (1): Wherein, R1 is selected from one of the groups represented by the general formula (2.1), general formula (2.2), general formula (2.3), and general formula (2.4): Ar1, Ar2, Ar3, and Ar4 are all aryl groups.
2. The preparation method of the rhodium-phosphine complex catalyst according to claim 1, wherein Ar1, Ar2, Ar3, and Ar4 are each independently selected from one of the molecules represented by the general formula (3): Wherein, R4 is a substituent.
3. The preparation method of the rhodium-phosphine complex catalyst according to claim 2, characterized in that, R2, R3, and R4 are each independently selected from a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a trifluoromethyl group, a nitro group, a sulfonic acid group, or a cyano group.
4. The preparation method of the rhodium-phosphine complex catalyst according to claim 1, characterized in that, The rhodium trihalide hydrate is at least one of rhodium trifluoride hydrate, rhodium trichloride hydrate, rhodium tribromide hydrate, and rhodium triiodide hydrate.
5. The preparation method of the rhodium-phosphine complex catalyst according to claim 1, characterized in that, The solvent of the alcohol solution of the bidentate phosphine ligand is at least one of methanol, ethanol, 1-propanol, isopropanol, 1,3-propanediol, 1-butanol, and 2-butanol.
6. The preparation method of the rhodium-phosphine complex catalyst according to claim 1, characterized in that, The concentration of the alcohol solution of the bidentate phosphine ligand is 0.15 to 3.0 mol / L.
7. The preparation method of the rhodium-phosphine complex catalyst according to claim 1, wherein The solvent of the formaldehyde solution is at least one of water and ethanol.
8. The preparation method of the rhodium-phosphine complex catalyst according to claim 1, wherein, The molar ratio of the bidentate phosphine ligand to the rhodium trihalide hydrate is 1.2 to 5.0:
1.
9. A rhodium-phosphine complex catalyst, characterized in that, The rhodium-phosphine complex catalyst is one of the molecules represented by the general formula (4): Wherein, R1 is selected from one of the groups represented by the general formula (2.1), general formula (2.2), general formula (2.3), and general formula (2.4): Ar1, Ar2, Ar3, and Ar4 are all aryl groups.
10. The rhodium-phosphine complex catalyst according to claim 9, characterized in that, Ar1, Ar2, Ar3, and Ar4 are each independently selected from one of the molecules represented by the general formula (3): Wherein, R4 is a substituent.
11. The rhodium-phosphine complex catalyst according to claim 10, wherein, R2, R3, and R4 are each independently selected from a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a trifluoromethyl group, a nitro group, a sulfonic acid group, or a cyano group.