Preparation method of supported Taniaphos ligand
The Taniaphos ligand is loaded onto the carrier under mild conditions through the Fuke alkylation reaction, which solves the problems of complex loading process and high cost, and realizes the efficient preparation and economical application of the loaded Taniaphos ligand.
Patent Information
- Application Number
- CN202510281987.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-11
- Publication Date
- 2025-06-10
AI Technical Summary
The loading process of Taniaphos ligand is complex and requires different reaction conditions to modify, resulting in high production costs and difficult to recycle, limiting its application in industrial production.
The complex of Taniaphos ligand and metal salt was loaded on a support under the conditions of Lewis acid, crosslinking agent, first solvent and second solvent to obtain a supported Taniaphos ligand without pre-modification of the ligand, and the reaction conditions were mild.
A one-step process is implemented to prepare load-type Taniaphos ligands, which reduces production costs, simplifies the process flow, and improves the economicality and reusability of the carrier.
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Figure CN120118133A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of organic chemistry, and particularly to a preparation method of a supported Taniaphos ligand. Background Art
[0002] The Taniaphos ligand is a chiral small molecule Taniaphos ligand with a very wide range of applications. However, due to the relatively complex structure of the Taniaphos ligand, its synthesis and purification may be relatively difficult, resulting in a high price for this type of ligand. At the same time, because the Taniaphos ligand is usually used as a homogeneous catalyst, that is, the Taniaphos ligand and the reactants are both dissolved in the same solvent to form a homogeneous solution system. This means that the Taniaphos ligand is difficult to recycle during the catalytic reaction process, greatly increasing the cost of this type of catalytic reaction. Therefore, it is still very challenging to apply this type of ligand with broad catalytic activity and wide application to industrial production.
[0003] Generally, the Taniaphos ligand can be supported on a solid carrier. The supported Taniaphos ligand catalyst is usually in the form of solid particles, which is convenient for separation and recovery from the reaction mixture. This can greatly reduce the use cost of the catalyst and enable it to be reused in multiple reaction cycles, increasing the economy of the catalyst.
[0004] At present, there are many problems in the loading of the Taniaphos ligand: the loading process is mostly relatively complex. The structure of the Taniaphos ligand can include various functional groups, such as carboxyl group, aldehyde group, amino group, phosphino group, alkyl group, etc. The chemical properties of these functional groups vary greatly, and different reaction conditions (such as temperature, pH value, catalyst, solvent, etc.) are required for modification, further increasing the production cost of the ligand. Summary of the Invention
[0005] Based on this, it is necessary to provide a preparation method of a supported Taniaphos ligand that does not require pre-modification of the ligand and has mild reaction conditions.
[0006] To achieve the above object, the present invention provides a technical solution:
[0007] A preparation method of a supported Taniaphos ligand, the preparation method of the supported Taniaphos ligand includes the steps of: under the conditions of a Lewis acid, a crosslinking agent, a first solvent and a second solvent, through a Friedel-Crafts alkylation reaction, loading a complex of the Taniaphos ligand and a metal salt on a carrier to obtain the supported Taniaphos ligand;
[0008] Wherein, the structural formula of the carrier is
[0009] The structural formula of the Taniaphos ligand is
[0010] The structural formula of the supported Taniaphos ligand is
[0011] R is a conjugated olefin group;
[0012] The range of a is 1 - 99;
[0013] The range of b is 1 - 99.
[0014] Specifically, the dosage of the Taniaphos ligand is 1 eq, and the dosage of the metal salt is 0.5 eq - 1 eq. More specifically, "eq" represents equivalent weight or molar multiple.
[0015] Furthermore, the specific steps of the preparation method of the supported Taniaphos ligand include:
[0016] At room temperature, add the Taniaphos ligand and the metal salt into the first solvent, and stir at room temperature for 10 - 60 min to obtain a complex of the ligand and the metal;
[0017] Dissolve the complex of the ligand and the metal in the second solvent, add the carrier and the crosslinking agent to obtain a reaction solution;
[0018] Add Lewis acid to the reaction solution to carry out Friedel - Crafts alkylation reaction to obtain the supported Taniaphos ligand;
[0019] The reaction equation is as follows:
[0020]
[0021] Wherein, is the complex of the ligand and the metal.
[0022] Furthermore, the specific steps of the preparation method of the supported Taniaphos ligand include:
[0023] Add the Taniaphos ligand into the second solvent, stir at room temperature until completely dissolved, then add the carrier and the crosslinking agent to obtain a reaction solution;
[0024] Add Lewis acid to the reaction solution to carry out Friedel - Crafts alkylation reaction to obtain the Taniaphos ligand supported on the carrier;
[0025] Dissolve the Taniaphos ligand supported on the carrier and the metal salt in the first solvent, and stir at room temperature for 10 - 60 min to obtain the supported Taniaphos ligand;
[0026] The reaction equation is as follows:
[0027]
[0028] Wherein, is the Taniaphos ligand supported on the carrier.
[0029] Furthermore, the reaction time of the Friedel-Crafts alkylation reaction is 1 h to 24 h, and the reaction is quenched using a quenching agent, which includes at least one of absolute ethanol, absolute methanol, hydrochloric acid aqueous solution, and ammonium chloride aqueous solution.
[0030] Furthermore, the reaction temperature of the Friedel-Crafts alkylation reaction is -50 °C to 80 °C.
[0031] Furthermore, R includes at least one of divinylphenyl, 1,3-butadienyl, isoprenyl, ethylene-trans-buteneyl, acroleinyl, and styryl and their derivative groups.
[0032] Furthermore, the Lewis acid includes at least one of aluminum trichloride, iron trichloride, tin tetrachloride, concentrated sulfuric acid, and trifluoromethanesulfonic acid.
[0033] Furthermore, the crosslinking agent includes at least one of dimethoxymethane, 1,4-dichloromethylbenzene, dichloromethane, chloroform, (4,4')-chloromethylbiphenyl, and (4,4')-benzyloxymethoxybiphenyl.
[0034] Furthermore, the metal salt includes at least one of copper(I) bromide dimethyl sulfide complex, cuprous chloride, copper(II) 2,5-thiophenedicarboxylate, copper(I) tetraethylammonium tetrafluoroborate, copper(I) tetraethylammonium hexafluorophosphate, bis(cyclopentadienyl)rhodium(I) tetrafluoroborate, dichloro(1,5-cyclooctadiene)rhodium(I) dimer, and dichloro(1,5-cyclooctadiene)iridium(I) dimer.
[0035] Furthermore, the first solvent includes at least one of dichloromethane, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, petroleum ether, diethyl ether, chloroform, 1,2-dichloroethane, nitromethane, nitrobenzene, and carbon tetrachloride, and the second solvent includes at least one of dichloromethane, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, petroleum ether, diethyl ether, chloroform, 1,2-dichloroethane, nitromethane, nitrobenzene, and carbon tetrachloride.
[0036] Advantages of the present invention:
[0037] Based on the Friedel-Crafts alkylation reaction, the present invention provides a one-step method for preparing a supported Taniaphos ligand. Compared with the traditional covalent bond loading of chiral ligands, this method has the advantages of not requiring pre-modification of the ligand, mild reaction conditions, cheap and easily available carriers with diverse structures, and easy regulation of ligand loading.
[0038] Through the screening of the carrier structure, reaction temperature, ligand / carrier ratio, reaction solvent, and crosslinking agent, a class of supported Taniaphos catalysts with diverse structures and stable mechanical properties was obtained in the present invention. Description of the Drawings
[0039] Figure 1 are the reaction equations for some examples;
[0040] Figure 2 are the reaction equations for some examples. Detailed Embodiments
[0041] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific examples.
[0042] In the examples, unless otherwise specified, the test methods used are all conventional methods, and the materials, reagents, etc. used, unless otherwise specified, can all be obtained from commercial channels.
[0043] A preparation method of a supported Taniaphos ligand, the preparation method of the supported Taniaphos ligand includes the steps of: under the conditions of a Lewis acid, a crosslinking agent, a first solvent, and a second solvent, through a Friedel-Crafts alkylation reaction, a complex of a Taniaphos ligand and a metal salt is loaded on a carrier to obtain a supported Taniaphos ligand;
[0044] wherein, the structural formula of the carrier is
[0045] The structural formula of the Taniaphos ligand is
[0046] The structural formula of the supported Taniaphos ligand is
[0047] R is a conjugated olefin group;
[0048] The range of a is 1 to 99;
[0049] The range of b is 1 to 99.
[0050] Specifically, the dosage of the Taniaphos ligand is 1 eq, and the dosage of the metal salt is 0.5 eq to 1 eq.
[0051] Further, the specific steps of the preparation method of the supported Taniaphos ligand include:
[0052] At room temperature, add the Taniaphos ligand and the metal salt into the first solvent, and stir at room temperature for 10 - 60 min to obtain the complex of the ligand and the metal;
[0053] Dissolve the complex of the ligand and the metal in the second solvent, add the carrier and the crosslinking agent to obtain a reaction solution;
[0054] Add Lewis acid to the reaction solution to carry out the Friedel - Crafts alkylation reaction to obtain the supported Taniaphos ligand;
[0055] The reaction equation is as follows:
[0056]
[0057] Among them, is the complex of the ligand and the metal.
[0058] Furthermore, the specific steps of the preparation method of the supported Taniaphos ligand include:
[0059] Add the Taniaphos ligand into the second solvent, stir at room temperature until completely dissolved, then add the carrier and the crosslinking agent to obtain a reaction solution;
[0060] Add Lewis acid to the reaction solution to carry out the Friedel - Crafts alkylation reaction to obtain the Taniaphos ligand supported on the carrier;
[0061] Dissolve the Taniaphos ligand supported on the carrier and the metal salt in the first solvent, and stir at room temperature for 10 - 60 min to obtain the supported Taniaphos ligand;
[0062] The reaction equation is as follows:
[0063]
[0064] Among them, is the Taniaphos ligand supported on the carrier.
[0065] More specifically, as shown in Figure 1 and Figure 2 the present invention relates to the co - loading of two compounds with different properties, namely the ligand and the metal, so it can be divided into two synthesis schemes:
[0066] 1. First, coordinate the metal with the Taniaphos ligand, and then load the complex onto the carrier;
[0067] 2. First, load the ligand small molecule, and then combine the metal with the ligand through a coordination bond to achieve the loading of the complex.
[0068] These two schemes have their own advantages and disadvantages. In Scheme 1, the binding between the ligand and the metal is stable, the structure is determined, there is less free metal, the catalyst is stable and efficient, and the active species is single. However, for different ligand / metal complexes, separate coordination synthesis is required, and the method is rather cumbersome. In Scheme 2, it is easier to be derived to the synthesis of different ligand / metal complexes, but during the coordination process of the metal with the ligand, a large amount of free metal or metal nanoparticles are easily adsorbed by the carrier, and the catalytic active species is not single.
[0069] Further, the reaction time of the Friedel-Crafts alkylation reaction is 1 h to 24 h, and the reaction is quenched using a quenching agent, and the quenching agent includes at least one of absolute ethanol, absolute methanol, aqueous hydrochloric acid, and aqueous ammonium chloride.
[0070] Further, the reaction temperature of the Friedel-Crafts alkylation reaction is -50°C to 80°C.
[0071] Further, R includes at least one of divinylphenyl, 1,3-butadienyl, isoprenyl, ethylene-trans-buteneyl, acryloyl, styryl, and their derivative groups.
[0072] Further, the Lewis acid includes at least one of aluminum trichloride, iron trichloride, tin tetrachloride, concentrated sulfuric acid, and trifluoromethanesulfonic acid.
[0073] Further, the crosslinking agent includes at least one of dimethoxymethane, 1,4-dichloromethylbenzene, dichloromethane, trichloromethane, (4,4')-chloromethylbiphenyl, and (4,4')-benzyloxymethoxybiphenyl.
[0074] Further, the metal salt includes at least one of copper(I) dimethyl sulfide bromide, cuprous chloride, copper(II) thiophene-2,5-dicarboxylate, copper(I) tetraethylammonium tetrafluoroborate, copper(I) tetraethylammonium hexafluorophosphate, rhodium(I) bis(cyclopentadienyl)tetrafluoroborate, rhodium(I) dichloride dimer, and iridium(I) dichloride dimer.
[0075] Further, the first solvent includes at least one of dichloromethane, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, petroleum ether, diethyl ether, trichloromethane, 1,2-dichloroethane, nitromethane, nitrobenzene, and carbon tetrachloride, and the second solvent includes at least one of dichloromethane, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, petroleum ether, diethyl ether, trichloromethane, 1,2-dichloroethane, nitromethane, nitrobenzene, and carbon tetrachloride.
[0076] Example 1
[0077] Weigh the Taniaphos ligand (15 mg) and cuprous chloride (CuCl, 2 mg) in a reaction tube at room temperature. Replace the air with nitrogen three times, add 2 ml of anhydrous dichloromethane as the solvent, and stir at room temperature for 30 min to obtain the complex L / Cu+ of the ligand and the metal.
[0078] Then add 65 mg of the support (the structural formula of the support is where a = 99, b = 1, and R is divinylphenyl) and 10 μL of dimethoxymethane to the reaction solution. After stirring at room temperature for 10 min, add 75 mg of anhydrous ferric chloride.
[0079] After reacting at room temperature for 4 h, add anhydrous ethanol to quench the reaction solution, and perform centrifugal separation. The solid is washed alternately with dichloromethane and anhydrous ethanol and then Soxhlet extracted with anhydrous ethanol for 48 h to obtain yellow particles, namely 75 mg of the supported Taniaphos ligand: S-L / M-1 (M = CuCl). ICP-OES test shows that the Cu loading in the catalyst is 0.035 mmol / g and the P loading is 0.94 mmol / g.
[0080] Example 2
[0081] Weigh the Taniaphos ligand (15 mg) and copper(I) bromide dimethyl sulfide complex (CuBr·SMe 2 , 4 mg) in a reaction tube at room temperature. Replace the air with nitrogen three times, add 2 ml of anhydrous 1,2-dichloroethane, and stir at room temperature for 30 min to obtain the complex L / Cu+ of the ligand and the metal.
[0082] Then add 65 mg of the support (the structural formula of the support is where a = 83, b = 17, and R is 1,3-butadiene) and 40 mg of 4,4'-chloromethylbiphenyl to the reaction solution. After stirring at room temperature for 10 min, cool the temperature to -30 °C, and add 100 mg of anhydrous aluminum trichloride.
[0083] After reacting at -30 °C for 12 h, add anhydrous ethanol to quench the reaction solution, and perform centrifugal separation. The solid is washed alternately with dichloromethane and anhydrous ethanol and then Soxhlet extracted with anhydrous ethanol for 48 h to obtain 100 mg of orange-yellow particles of the supported Taniaphos ligand S-L / M-1 (M = CuBr·SMe 2 ). ICP-OES test shows that the Cu loading in the catalyst is 0.075 mmol / g and the P loading is 0.164 mmol / g.
[0084] Example 3
[0085] Weigh the Taniaphos ligand (15 mg) and rhodium(I) bis(η²-2,5-norbornadiene) tetrafluoroborate ([Rh(nbd) 2BF 4 , 8 mg) was placed in a reaction tube, purged with nitrogen three times, anhydrous nitrobenzene (2 ml) was added, and the mixture was stirred at room temperature for 30 min to obtain a complex of ligand and metal, L / Rh+.
[0086] Then, a carrier (the structural formula of the carrier is where a = 13, b = 87, and R is isoprenyl) 150 mg and 1,4-dibenzyloxymethoxybenzene (30 mg) were added to the reaction solution. After stirring at room temperature for 10 min, the temperature was raised to 60 °C, and concentrated sulfuric acid (30 μL) was added.
[0087] After reacting at 60 °C for 8 h, anhydrous ethanol was added to quench the reaction solution. After centrifugation, the solid was washed alternately with dichloromethane and anhydrous ethanol and then Soxhlet extracted with dichloromethane for 48 h to obtain orange granular supported Taniaphos ligand S-L / M-1 (M = [Rh(nbd) 2 BF 4 ) 175 mg. The Rh loading in the catalyst was determined to be 0.032 mmol / g and the P loading was 0.068 mmol / g by ICP-OES measurement.
[0088] Example 4
[0089] At room temperature, Taniaphos ligand (15 mg) and iridium(III) chloride dimer, 1,5-cyclooctadiene complex (M = [Ir(cod)Cl] 2 , 9 mg) were placed in a reaction tube, purged with nitrogen three times, nitromethane (2 ml) was added, and the mixture was stirred at room temperature for 60 min to obtain a complex of ligand and metal, L / Ir + .
[0090] Then, a carrier (the structural formula of the carrier is where a = 22, b = 78, and R is isoprenyl) 150 mg and 1,4-dichloromethylbenzene (30 mg) were added to the reaction solution. After stirring at room temperature for 60 min, the temperature was lowered to -50 °C, and anhydrous aluminum trichloride (80 mg) was added.
[0091] After reacting at -50 °C for 24 h, anhydrous ethanol was added to quench the reaction solution. After centrifugation, the solid was washed alternately with dichloromethane and anhydrous ethanol and then Soxhlet extracted with anhydrous ethanol for 48 h to obtain yellow granular supported Taniaphos ligand S-L / M-1 (M = [Ir(cod)] 2 ) 180 mg. The Ir loading in the catalyst was determined to be 0.035 mmol / g and the P loading was 0.072 mmol / g by ICP-OES measurement.
[0092] Example 5
[0093] Weigh the Taniaphos ligand (15 mg) into a reaction tube. After replacing the gas with argon three times, add chloroform (2 mL) to dissolve it. After stirring at room temperature for 10 min, add the carrier (the structural formula of the carrier is where a = 99, b = 1, and R is divinylphenyl) 70 mg. After stirring at room temperature for 15 min, add trifluoromethanesulfonic acid (30 μL). After stirring and heating to 50 °C and reacting for 12 h, add absolute ethanol to quench the reaction solution. Centrifuge, and extract the solid with absolute ethanol in a Soxhlet extractor for 48 h to obtain the supported Taniaphos ligand catalyst S-L.
[0094] Weigh the ligand S-L (30 mg) and copper(I) bromide dimethyl sulfide (1 mg) at room temperature into a reaction tube. After replacing the gas with an inert gas (nitrogen or argon) three times, add anhydrous toluene (1 mL) as the solvent. After stirring at room temperature for 60 min, filter by suction. Wash the filter cake alternately with absolute ethanol and dichloromethane to obtain the supported Taniaphos ligand catalyst S-L / M-2 (M = copper(I) bromide dimethyl sulfide). ICP-OES test shows that the Cu loading in the catalyst is 0.12 mmol / g, and the P loading is 0.211 mmol / g.
[0095] Example 6
[0096] Weigh the Taniaphos ligand (15 mg) into a reaction tube. After replacing the gas with argon three times, add 1,2-dichloroethane (2 mL) to dissolve it. After stirring at room temperature for 10 min, add the carrier (the structural formula of the carrier is where a = 98, b = 2, and R is divinylphenyl) 70 mg. After stirring at room temperature for 15 min, cool down to 0 °C, add dimethoxymethane and tin(IV) chloride. After reacting at 0 °C for 8 h, add absolute ethanol to quench the reaction solution. Centrifuge, and extract the solid with absolute ethanol in a Soxhlet extractor for 48 h to obtain the supported catalyst S-L.
[0097] Weigh the ligand S-L (30 mg) and copper(I) chloride (0.8 mg) at room temperature into a reaction tube. After replacing the gas with inert argon three times, add anhydrous dichloromethane (1 mL) to disperse the catalyst. Stir at room temperature for 60 min, filter by suction. Wash the filter cake alternately with dichloromethane and absolute ethanol to obtain the supported Taniaphos ligand catalyst S-L / M-2 (M = copper(I) chloride). ICP-OES test shows that the Ir loading in the catalyst is 0.201 mmol / g, and the P loading is 0.325 mmol / g.
[0098] Example 7
[0099] Weigh the Taniaphos ligand (15 mg) into a reaction tube. After replacing the gas with argon three times, add chloroform (2 mL) to dissolve it. After stirring at room temperature for 10 min, add the carrier (the structural formula of the carrier is Among them, a = 95, b = 58, 70 mg of divinylphenyl) and 20 mg of crosslinking agent dimethoxymethane were stirred at room temperature for 15 min, then 30 μL of trifluoromethanesulfonic acid was added, and the mixture was stirred and heated to 50 °C for reaction for 12 h. Then, absolute ethanol was added to quench the reaction solution, and after centrifugation, the solid was extracted with absolute ethanol in a Soxhlet extractor for 48 h to obtain the Taniaphos ligand supported on the carrier.
[0100] At room temperature, 30 mg of the Taniaphos ligand supported on the carrier and 2 mg of rhodium bis(cyclopentadienyl) tetrafluoroborate were weighed into a reaction tube, purged with inert argon three times, 1 ml of anhydrous tetrahydrofuran was added to disperse the catalyst, and the mixture was stirred at room temperature for 60 min. Then, filtration was carried out, and the filter cake was washed alternately with dichloromethane and absolute ethanol to obtain the supported Taniaphos ligand catalyst (i.e., S-L / M-2, M = cuprous chloride). ICP-OES test showed that the Cu loading in the catalyst was 0.045 mmol / g and the P loading was 0.091 mmol / g.
[0101] Through the screening of the carrier structure, reaction temperature, ligand / carrier ratio, reaction solvent and crosslinking agent, the present invention obtained a class of supported Taniaphos catalysts with diverse structures and stable mechanical properties.
[0102] Comparative Example 1
[0103] At room temperature, 15 mg of Taniaphos ligand and 4 mg of cuprous bromide dimethyl sulfide were weighed into a reaction tube, purged with nitrogen three times, 2 ml of anhydrous 1,2-dichloroethane was added, and the mixture was stirred at room temperature for 30 min to obtain a complex L / Cu of the ligand and the metal. + 。
[0104] Then, a carrier (the structural formula of the carrier is Among them, a = 23, b = 77, and R is 1,3-butadienyl) 65 mg and dimethoxymethane (40 mg) were added to the reaction solution. After stirring at room temperature for 10 min, the temperature was lowered to -30 °C, and 100 mg of anhydrous aluminum trichloride was added.
[0105] After reacting at -30 °C for 12 h, absolute ethanol was added to quench the reaction solution, and after centrifugal separation, the solid was washed alternately with dichloromethane and absolute ethanol to obtain a white powdery solid. ICP-OES test showed that the Cu loading in the catalyst was 0.002 mmol / g and the P loading was 0.003 mmol / g.
[0106] Since the Taniaphos ligand itself is orange-yellow, the catalyst obtained after successful immobilization should be a yellow to orange-yellow powder, but a white powder was obtained this time.
[0107] This immobilization reaction condition is not appropriate. It may be that the reaction temperature is too low, resulting in no reaction between the ligand and the carrier.
[0108] Comparative Example 2
[0109] Weigh the Taniaphos ligand (15 mg) into a reaction tube, displace the gas with argon three times, add tetrahydrofuran (2 mL) to dissolve it, stir at room temperature for 10 min, then add the support (the structural formula of the support is where a = 90, b = 10, and R is divinylphenyl) 70 mg. After stirring at room temperature for 15 min, add iron(III) chloride (65 mg). Stir and heat up to room temperature, react for 12 h, then add anhydrous ethanol to quench the reaction solution, and centrifuge to obtain 70 mg of a white powdery solid. The mass of the support did not increase and the color did not change either, indicating that this loading condition is not suitable.
[0110] This is because tetrahydrofuran complexes with iron(III) chloride, deactivating the iron(III) chloride and thus preventing it from catalyzing the Friedel-Crafts alkylation reaction between the ligand and the support.
[0111] Application of the supported Taniaphos ligand catalyst in chemical reactions
[0112] The chemical reaction equation is as follows:
[0113]
[0114] The structural formula of the supported Taniaphos ligand catalyst is as follows:
[0115]
[0116] The specific experimental operations are as follows:
[0117] Weigh 50 mg of the supported Taniaphos ligand catalyst into a reaction tube at room temperature. After displacing the gas with argon three times, add 2 mL of anhydrous dichloromethane to suspend the supported Taniaphos ligand catalyst. Cool down to -78 °C, and slowly add 0.2 mL of a diethyl ether solution of 3 M methylmagnesium bromide to the reaction solution. Use a syringe pump to add 0.5 mL of a dichloromethane solution containing cinnamyl bromide to the reaction solution, and the feeding time is 0.5 h. After the feeding is completed, continue to react at -78 °C for 8 h. Quench the reaction solution with hydrochloric acid, and separate the product by column chromatography to obtain a colorless oil, with a yield of 90% and an ee of the product of 97%.
[0118] To verify the stability of the supported Taniaphos ligand catalyst, we also carried out a catalyst recycling experiment. After the reaction was complete, quench the reaction solution with 1 M hydrochloric acid aqueous solution, filter by suction. Wash the filter cake alternately with anhydrous ethanol and dichloromethane, and then dry it in vacuo at 40 °C for 24 hours for the next cycle (the steps are the same as the above steps). Cycle 5 times, and the results are shown in Table 1.
[0119] Table 1 Recycling results
[0120]
[0121]
[0122] It should be noted that the specific parameters or some reagents in the above embodiments are specific embodiments or preferred embodiments under the concept of the present invention, rather than limitations thereto; those skilled in the art can make adaptive adjustments within the concept and protection scope of the present invention.
Claims
1. A method for preparing a supported Taniaphos ligand, characterized in that: The preparation method of the supported Taniaphos ligand comprises the steps of: loading a complex of the Taniaphos ligand and a metal salt on a carrier by Friedel-Crafts alkylation reaction under the conditions of a Lewis acid, a cross-linking agent, a first solvent and a second solvent to obtain the supported Taniaphos ligand; Wherein, the structural formula of the carrier is The structural formula of the Taniaphos ligand is The structural formula of the supported Taniaphos ligand is R is a conjugated olefin group; a ranges from 1 to 99; The range of b is 1 to 99.
2. The method for preparing a supported Taniaphos ligand according to claim 1, characterized in that: The preparation method of the supported Taniaphos ligand specifically comprises the following steps: At room temperature, adding the Taniaphos ligand and the metal salt into the first solvent, stirring at room temperature for 10-60 minutes, to obtain a complex of the ligand and the metal; dissolving the complex of the ligand and the metal in a second solvent, adding a carrier and a cross-linking agent to obtain a reaction solution; Adding Lewis acid to the reaction solution to cause Friedel-Crafts alkylation reaction to obtain a supported Taniaphos ligand; The reaction equation is as follows: in, It is a complex of ligand and metal.
3. The method for preparing the supported Taniaphos ligand according to claim 1, characterized in that: The preparation method of the supported Taniaphos ligand specifically comprises the following steps: The Taniaphos ligand is added to the second solvent, stirred at room temperature until completely dissolved, and then a carrier and a cross-linking agent are added to obtain a reaction solution; Adding Lewis acid to the reaction solution to cause Friedel-Crafts alkylation reaction to obtain a carrier-supported Taniaphos ligand; Dissolving the carrier-supported Taniaphos ligand and the metal salt in a first solvent, and stirring at room temperature for 10-60 min to obtain a supported Taniaphos ligand; The reaction equation is as follows: in, Taniaphos ligand loaded on the carrier.
4. The method for preparing a supported Taniaphos ligand according to claim 1, characterized in that: The reaction time of the Friedel-Crafts alkylation reaction is 1 h to 24 h, and a quencher is used to quench the reaction. The quencher includes at least one of anhydrous ethanol, anhydrous methanol, a hydrochloric acid aqueous solution and an ammonium chloride aqueous solution.
5. The method for preparing the supported Taniaphos ligand according to claim 1, characterized in that: The reaction temperature of the Friedel-Crafts alkylation reaction is -50°C to 80°C.
6. The method for preparing a supported Taniaphos ligand according to claim 1, characterized in that: R includes at least one of divinylphenyl, 1,3-butadienyl, isoprenyl, ethylene-trans-butenyl, acryl, styryl and derivatives thereof.
7. The method for preparing a supported Taniaphos ligand according to claim 1, characterized in that: The Lewis acid includes at least one of aluminum trichloride, ferric trichloride, tin tetrachloride, concentrated sulfuric acid and trifluoromethanesulfonic acid.
8. The method for preparing a supported Taniaphos ligand according to claim 1, characterized in that: The crosslinking agent includes at least one of dimethoxymethane, 1,4-dichloromethylbenzene, dichloromethane, chloroform, (4,4')-chloromethylbiphenyl and (4,4')-benzylmethoxybiphenyl.
9. The method for preparing a supported Taniaphos ligand according to claim 1, characterized in that: The metal salt includes at least one of cuprous bromide dimethyl sulfide, cuprous chloride, cuprous thiophenedicarboxylate, copper tetraacetonitrile tetrafluoroborate, copper tetraacetonitrile hexafluorophosphate, bis(dicyclopentadiene)rhodium tetrafluoroborate, 1,5-cyclooctadiene rhodium chloride dimer, and 1,5-cyclooctadiene iridium chloride dimer.
10. The method for preparing a supported Taniaphos ligand according to claim 1, characterized in that: The first solvent includes at least one of dichloromethane, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, petroleum ether, ethyl ether, chloroform, 1,2-dichloroethane, nitromethane, nitrobenzene and carbon tetrachloride, and the second solvent includes at least one of dichloromethane, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, petroleum ether, ethyl ether, chloroform, 1,2-dichloroethane, nitromethane, nitrobenzene and carbon tetrachloride.