Covalent organic framework phosphine ligand and preparation method thereof, heterogeneous catalyst containing ligand and preparation method and application of heterogeneous catalyst

Abstract

The invention relates to a covalent organic framework phosphine ligand, a preparation method of the covalent organic framework phosphine ligand, a heterogeneous catalyst containing the covalent organic framework phosphine ligand and a preparation method and application of the heterogeneous catalyst, and belongs to the technical field of heterogeneous catalysts. The catalyst comprises a covalent organic framework phosphine ligand and a metal active component Rh loaded on the covalent organic framework phosphine ligand, and the covalent organic framework phosphine ligand has a structure as shown in a formula (1) or a formula (2). The catalyst belongs to a covalent organic framework (COF) catalyst, and has the following advantages: 1) the catalyst can be repeatedly used through suction filtration separation after the reaction is completed, and 2) the phosphine ligand of the covalent organic framework with a highly ordered crystal structure has a large surface area and a clear porosity, can effectively adsorb H2 / CO, and can be used for preparing the catalyst for the high-performance organic framework. More reaction sites are provided, the hydroformylation reaction of high-carbon-chain olefin (C6 or above) is facilitated, and the catalytic performance is improved.

Description

Technical Field

[0001] The invention relates to the technical field of heterogeneous catalysts, and in particular to the preparation and application of a covalent organic framework phosphine ligand-Rh-based heterogeneous catalyst containing multiple coordination sites. Background Art

[0002] High carbon aldehydes are important organic chemical raw materials for many high value-added fine chemical products. Tridecanal in high carbon aldehydes is prepared by hydroformylation of dodecene. At present, the catalysts used in hydroformylation of dodecene are mainly traditional homogeneous catalysts and water-oil two-phase catalysts. Traditional homogeneous catalysis has many shortcomings, such as difficulty in separating the catalyst from the reaction product and difficulty in reusing the catalyst. Although the water-oil two-phase catalyst can separate the catalyst from the reaction liquid and reuse the catalyst, it has the disadvantages of low yield and low selectivity due to the poor compatibility of the catalyst with dodecene.

[0003] Isononanal in high carbon aldehydes is prepared by isooctene hydroformylation reaction. Currently, homogeneous catalytic systems, water / oil two-phase catalytic systems, and multiphase solid-supported catalytic systems are commonly used. However, the existing catalytic systems have problems such as low conversion rate and product selectivity of isooctene hydroformylation, high catalyst production cost, and difficulty in catalyst separation. Therefore, it is very important to prepare ligands and catalysts with easy separation, high conversion rate, and high selectivity for the conversion rate of isooctene and the selectivity of isononanal. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, one of the purposes of the present invention is to provide a covalent organic framework phosphine ligand, which contains multiple coordination sites as reaction sites, and can solve the problems of reduced activity and loss of active components, that is, the problem of poor reaction stability. The second purpose of the present invention is to provide a method for preparing a covalent organic framework phosphine ligand. The third purpose of the present invention is to provide a multiphase catalyst, which has a ligand with a specific structure and a metal active component loaded on the ligand. The catalyst has a covalent organic framework and has the advantages of easy separation, high conversion rate and high selectivity; the fourth purpose of the present invention is to provide a method for preparing a multiphase catalyst; the fifth purpose of the present invention is to provide an application of a multiphase catalyst, which is suitable for the hydroformylation reaction of high-carbon olefins, and the multi-reaction site can improve the conversion rate of olefins and the selectivity of aldehydes.

[0005] One of the purposes of the present invention is achieved by the following technical solution:

[0006] A covalent organic framework phosphine ligand, the structural formula of which is shown in formula (1) or formula (2):

[0007]

[0008] Among them, R1 is at least one of a straight chain / branched alkyl group, a cycloalkyl group, a heterocyclic group, a heterocycloalkyl group, an aryl group, a substituted aryl group and their derivatives; R2 is at least one of a hydrogen, a straight chain / branched alkyl group, a cycloalkyl group, a heterocyclic group, a heterocycloalkyl group, an aryl group, a substituted aryl group and their derivatives.

[0009] Preferably, the R1 is at least one of a methyl group, a methine group and an ethyl group.

[0010] Preferably, R2 is at least one of hydrogen, methyl, ethyl, propyl and trifluoromethyl.

[0011] The second object of the present invention is achieved by adopting the following technical solution:

[0012] The method for preparing the covalent organic framework phosphine ligand comprises the following steps:

[0013] (1) iodobenzonitrile containing an active group is first reacted with isopropylmagnesium chloride and phosphorus trichloride to generate triphenylphosphine carbonitrile containing an active group; wherein the mass ratio / molar ratio of iodobenzonitrile containing an active group, isopropylmagnesium chloride and phosphorus trichloride is 1:1-2:0.1-0.5;

[0014] (2) The triphenylphosphine nitrile containing an active group generates a covalent organic framework phosphine ligand containing multiple coordination sites under the action of trifluoromethanesulfonic acid; wherein the mass ratio / molar ratio of the triphenylphosphine nitrile containing an active group and trifluoromethanesulfonic acid is 1:1-2:0.1-0.5.

[0015] Preferably, the active group comprises a phosphite group. In the iodobenzonitrile containing an active group, the active group comprises a phosphite group.

[0016] Preferably, in the step (1), the isopropyl magnesium chloride is added dropwise to a solution of iodobenzonitrile containing an active group, stirred, and then phosphorus trichloride is added dropwise to obtain a reaction solution, and the temperature during the dropping process is -50 to -30°C, and the temperature is more preferably -40°C; after the dropping is completed, the reaction solution is heated to 20 to 30°C and continued to be stirred. The heating temperature is room temperature, not limited to 20 to 30°C; after the reaction is completed, the reaction solution is cooled and hydrochloric acid is added to quench, and then extraction, washing, drying, and vacuum concentration are performed in sequence to obtain a crude product, and after purification, a solid triphenylphosphine carbonitrile containing an active group is obtained.

[0017] And / or, in the step (2), the triphenylphosphine cyanide containing an active group is added to a solvent to prepare a solution, trifluoromethanesulfonic acid is added dropwise to the solution at -1 to 5°C, more preferably at 0°C; the solution is kept at 20 to 40°C for 2 to 6 days, more preferably at 30°C for 4 days to obtain a mixture; after the reaction is completed, the mixture is neutralized with lithium hydroxide and stirred at 20 to 30°C, the heating temperature is room temperature, not limited to 20 to 30°C; the precipitate is filtered, collected, washed, and then dried to obtain a covalent organic framework phosphine ligand.

[0018] The third object of the present invention is achieved by adopting the following technical solution:

[0019] A multiphase catalyst comprises the covalent organic framework phosphine ligand and a metal active component loaded on the covalent organic framework phosphine ligand.

[0020] Preferably, the metal active ingredient is rhodium.

[0021] The fourth object of the present invention is achieved by adopting the following technical solution:

[0022] The method for preparing the heterogeneous catalyst comprises the following steps:

[0023] The covalent organic framework phosphine ligand is placed in a solution containing a metal active component for reaction, and the solvent is removed after the reaction to obtain a multiphase catalyst; wherein the mass ratio of the covalent organic framework phosphine ligand to the metal active component is 10 to 100:1.

[0024] Preferably, the reaction parameters are: temperature of 25 to 100° C., stirring time of 1 to 100 h, and / or the reaction is carried out under an argon atmosphere; and / or the solvent is removed by reduced pressure distillation; and / or the solution containing the metal active component is a tetrahydrofuran solution of acetylacetonato dicarbonyl rhodium.

[0025] The fifth object of the present invention is achieved by adopting the following technical solution:

[0026] The multiphase catalyst is used in the preparation of high carbon aldehydes.

[0027] Preferably, the application is to prepare tridecanal by hydroformylation of dodecene with dodecene, carbon monoxide and hydrogen in the presence of a heterogeneous catalyst. Preferably, the feed mass ratio of dodecene: carbon monoxide: hydrogen is 1:1-2:1-2; preferably, dodecene, carbon monoxide and hydrogen are contacted with the catalyst in an organic solvent for reaction; more preferably, the organic solvent comprises at least one of cyclohexane, benzene, toluene, ether, tetrahydrofuran and isononanal.

[0028] Preferably, the added amount of the heterogeneous catalyst is 0.05% to 10% of the mass of dodecene.

[0029] Preferably, the reaction parameters are as follows (I) to (III):

[0030] (I) the reaction temperature is 50 to 280°C, more preferably 90 to 160°C;

[0031] (II) The reaction pressure is 0.5 to 20 MPa, preferably 2 to 6 MPa;

[0032] (III) The reaction time is 0.5 to 100 hours, preferably 8 to 18 hours.

[0033] Preferably, the application is to prepare isononanal by isooctene hydroformylation reaction under the action of a multiphase catalyst using isooctene, carbon monoxide and hydrogen; preferably, the feed mass ratio of isooctene:carbon monoxide:hydrogen is 1:1-2:1-2; preferably, dodecene, carbon monoxide and hydrogen are contacted and reacted with the catalyst in an organic solvent; more preferably, the organic solvent includes at least one of cyclohexane, benzene, toluene, ether, tetrahydrofuran and isononanal.

[0034] Preferably, the added amount of the heterogeneous catalyst is 0.05% to 10% of the mass of isooctene.

[0035] Preferably, the reaction parameters are as follows (I) to (III):

[0036] (I) the reaction temperature is 50 to 250°C, more preferably 80 to 150°C;

[0037] (II) the reaction pressure is 0.5 to 10 MPa, more preferably 1 to 5 MPa;

[0038] (III) The reaction time is 1 to 100 hours, more preferably 8 to 15 hours.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] (1) The structure of the covalent organic framework phosphine ligand of the present invention is shown in Formula (1) or Formula (2), and the ligand has multiple coordination sites. The ligand has a covalent organic phosphine skeleton with a highly ordered crystal structure, which has a large surface area and a clear porosity and can effectively adsorb H2 / CO, providing more reaction sites.

[0041] (2) The multiphase catalyst of the present invention comprises a covalent organic framework phosphine ligand and a metal active component supported on the covalent organic framework phosphine ligand, so the catalyst belongs to a covalent organic framework (COF) catalyst, and the catalyst has the following advantages: 1) the covalent organic framework phosphine ligand-Rh multiphase catalyst can be separated by suction filtration after the reaction, so as to realize the reuse of the catalyst; 2) the covalent organic framework phosphine ligand with a highly ordered crystal structure has a large surface area and a clear porosity, which can effectively adsorb H2 / CO, provide more reaction sites, and is conducive to the hydroformylation reaction of high-carbon chain olefins (above C6), thereby improving the catalytic performance. 3) the controllable ordered pore structure thereof is conducive to the material transmission process, and can also improve the selectivity of aldehydes by controlling the pore size; 4) the covalent organic framework phosphine ligand containing multiple coordination sites can provide more sites for coordination with Rh, provide more reaction centers, and further improve the hydroformylation reaction rate and shorten the reaction time.

[0042] (3) The catalyst of the present invention adopts an impregnation method to load the metal active component on the covalent organic framework phosphine ligand, and the preparation method is simple and suitable for large-scale preparation.

[0043] (4) Preferably, a catalyst comprising a covalent organic framework phosphine ligand having a structure as shown in formula (1) is used in a heterogeneous catalytic reaction of preparing tridecanal by hydroformylation of dodecene, which can improve the conversion rate of dodecene and the selectivity of tridecanal. A catalyst comprising a ligand as shown in formula (2) is also used in the above reaction, but the conversion rate and selectivity are lower than those of the structure as shown in formula (1). This is because the phosphite substituent on the ligand in formula (1) plays a positive role, which is mainly attributed to the fact that the covalent organic framework phosphine ligand containing multiple coordination sites has more sites that can coordinate with Rh, thereby accelerating the hydroformylation reaction of dodecene.

[0044] (5) Preferably, a catalyst comprising a covalent organic framework phosphine ligand having a structure as shown in formula (2) is used in a heterogeneous catalytic reaction of preparing isononanal by hydroformylation of isooctene, and can improve the conversion rate of isooctene and the selectivity of isononanal compared with a catalyst without an organic framework phosphine ligand. A catalyst comprising a ligand as shown in formula (1) is also used in the above reaction, and the conversion rate and selectivity are higher than those of the structure as shown in formula (2). BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 The relationship between the number of times the catalyst P-COF2-Rh is reused and the catalytic performance of Example 2;

[0046] Figure 2 This is the relationship between the number of times the catalyst COF-P-1-Rh is reused and its catalytic performance in Example 6. DETAILED DESCRIPTION

[0047] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0048] A catalyst comprising a covalent organic framework phosphine ligand having a structure shown in formula (1) is used in a heterogeneous catalytic reaction of preparing tridecanal by hydroformylation of dodecene, which can improve the conversion rate of dodecene and the selectivity of tridecanal. The catalyst and its preparation method and application are shown in Examples 1 to 5, and the application examples based on the catalyst separation and reuse experiment of Example 2 are shown in Application Examples 1 to 9. The comparative examples corresponding to the catalysts of Examples 1 to 5 are Comparative Examples 1 to 2.

[0049]

[0051] The catalyst comprising a covalent organic framework phosphine ligand having a structure shown in formula (2) is applied to a heterogeneous catalytic reaction of preparing isononanal by hydroformylation of isooctene, and can improve the conversion rate of isooctene and the selectivity of isononanal. The catalyst and its preparation method are shown in Examples 6 to 10, and the application examples based on the catalyst separation and reuse experiment of Example 6 are shown in Application Examples 10 to 18. The corresponding comparative examples are Comparative Examples 4 to 5.

[0052]

[0053] Example 1

[0054] The preparation method of a covalent organic framework phosphine ligand containing multiple coordination sites comprises the following steps:

[0055] 1) Synthesis of triphenylphosphine carbonitrile containing phosphite group: 5-cyano-2-iodophenyl dimethyl phosphite (4.0 g, 11.86 mmol) was placed in a 100 mL three-necked flask, and 17.5 mL of tetrahydrofuran was added to completely dissolve 5-cyano-2-iodophenyl dimethyl phosphite. Subsequently, i-PrMgCl (14.2 mmol) was slowly added dropwise to the 5-cyano-2-iodophenyl dimethyl phosphite solution at -50 ° C / argon. After the addition was completed, the reaction solution was stirred for 40 min, and then a tetrahydrofuran solution of PCl3 (0.33 ml, 4.15 mmol) was added dropwise. After the addition was completed, the reaction solution was slowly heated to room temperature and stirred for 16 h. After the reaction was completed, the reaction solution was cooled to -1 °C and quenched by adding 1M HCl, extracted with ethyl acetate (3×30 mL), washed, dried, and concentrated in vacuo to obtain a crude product, which was purified by column chromatography to obtain triphenylphosphine carbonitrile containing a phosphite group (Compound 1) (1.05 g, 40%) as a colorless solid. 1H NMR (400 MHz, CDCl3) δ: 7.57 (dd, J1=6.0 Hz, J2=1.6 Hz, 3H, ArH), 7.45 (d, J=6.0 Hz, 3H, ArH), 7.37 (d, J=1.6 Hz, 3H, ArH), 3.62 (s, 18H, CH3).

[0056] 2) Synthesis of covalent organic framework phosphine ligands with multiple coordination sites:

[0057] Compound 1 (1.0 g, 1.51 mmol) was added to 40 mL of chloroform solution, and then 5 mL of trifluoromethanesulfonic acid was slowly added to the solution at -1 °C and kept at 20 °C for 6 days. After the reaction was completed, the mixture was neutralized with LiOH and stirred at room temperature for 24 h, and the yellow precipitate was collected by filtration, washed with a large amount of H2O, and then vacuum dried at 80 °C for 12 h to obtain the covalent organic framework phosphine ligand P-COF1. The synthesis route of the ligand is shown in formula (3).

[0058]

[0059] The method for preparing a heterogeneous catalyst comprises the following steps:

[0060] At 25°C and in an Ar gas atmosphere, 1.0 g of the above-prepared covalent organic framework phosphine ligand P-COF1 containing multiple coordination sites was added to a tetrahydrofuran (100 mL) solution containing 30 mg of acetylacetonato dicarbonyl rhodium and stirred for 24 h. Subsequently, the solvent was removed in vacuo at 50°C to obtain a heterogeneous catalyst (P-COF1-Rh) with a covalent organic framework phosphine ligand containing multiple coordination sites coordinated / loaded with a Rh metal component.

[0061] Application of the heterogeneous catalyst of this embodiment

[0062] Dodecene hydroformylation process

[0063] P-COF1-Rh is suitable for the hydroformylation reaction of C6-C14 high carbon olefins to prepare C7-C15 high carbon aldehydes. This embodiment takes dodecene as an example.

[0064] 50 mL of dodecene, 0.1 g of catalyst P-COF1-Rh and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. The carbon monoxide / hydrogen cylinder was connected and quickly heated to 90 ° C. At the same time, the system pressure was adjusted to 0.5 MPa, the stirring rate was 800 rpm, and maintained for 18 hours. After the reaction was completed, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid was extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 1.

[0065] Example 2

[0066] The preparation method of a covalent organic framework phosphine ligand containing multiple coordination sites comprises the following steps:

[0067] 1) Synthesis of triphenylphosphine carbonitrile containing phosphite group: 5-cyano-2-iodophenyl diethyl phosphite (4.0 g, 10.96 mmol) was placed in a 100 mL three-necked flask, and 17.0 mL of tetrahydrofuran was added to completely dissolve it. Subsequently, i-PrMgCl (17.0 mmol) was slowly added dropwise to the solution of 5-cyano-2-iodophenyl diethyl phosphite at -40 ° C / argon. After the addition was completed, the reaction solution was stirred for 40 min, and then a tetrahydrofuran solution of PCl3 (0.35 mL, 4.06 mmol) was added dropwise. After the addition was completed, the reaction solution was slowly heated to room temperature and stirred for 16 h. After the reaction was complete, the reaction solution was cooled to 0°C and quenched by adding 1M HCl, extracted with ethyl acetate (3×30 mL), washed, dried, and concentrated in vacuo to obtain a crude product, which was purified by column chromatography to obtain compound 2 (1.15 g, 45%) as a colorless solid. 1H NMR (400 MHz, CDCl3) δ: 7.56 (dd, J1=6.0 Hz, J2=1.6 Hz, 3H, ArH), 7.46 (d, J=6.0 Hz, 3H, ArH), 7.36 (d, J=1.6 Hz, 3H, ArH), 3.54 (q, J=6.0 Hz, 12H, CH2), 2.05 (t, J=6.0 Hz, 18H, CH3).

[0068] 2) Synthesis of a covalent organic framework phosphine ligand containing multiple coordination sites: Compound 2 (1.0 g, 1.34 mmol) obtained in step 1) was added to 40 mL of chloroform solution, and then 8 mL of trifluoromethanesulfonic acid was slowly added dropwise to the solution at 0°C and kept at 30°C for 4 days. After the reaction was completed, the mixture was neutralized with LiOH and stirred at room temperature for 24 h, and the yellow precipitate was collected by filtration, washed with a large amount of H2O, and then vacuum dried at 80°C for 12 h to obtain a covalent organic framework phosphine ligand P-COF2. The specific synthesis route is shown in formula (4).

[0069]

[0070] A method for preparing a heterogeneous catalyst comprises the following steps:

[0071] At 25°C and in an Ar gas atmosphere, 1.0 g of the above-prepared covalent organic framework phosphine ligand P-COF2 containing multiple coordination sites was added to a tetrahydrofuran (100 mL) solution containing 30 mg of acetylacetonato dicarbonyl rhodium and stirred for 24 hours. Subsequently, the solvent was removed in vacuo at 50°C to obtain a heterogeneous catalyst (P-COF2-Rh) with a covalent organic framework phosphine ligand containing multiple coordination sites coordinated / loaded with a Rh metal component.

[0072] Application of heterogeneous catalysts

[0073] The catalyst P-COF2-Rh is suitable for the hydroformylation reaction of C6-C14 high carbon olefins to prepare C7-C15 high carbon aldehydes. This embodiment takes dodecene as an example.

[0074] 50 mL of dodecene, 0.1 g of catalyst P-COF2-Rh and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. The carbon monoxide / hydrogen cylinder was connected and quickly heated to 130 ° C. At the same time, the system pressure was adjusted to 3.5 MPa, the stirring rate was 800 rpm, and maintained for 10 hours. After the reaction was completed, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid was extracted and processed for gas chromatography analysis. The data results are recorded in Table 1.

[0075] Example 3

[0076] The preparation method of a covalent organic framework phosphine ligand containing multiple coordination sites comprises the following steps:

[0077] 1) Synthesis of triphenylphosphine carbonitrile containing phosphite group: 5-cyano-2-iodophenyl dioxaethyl phosphite (4.0 g, 11.9 mmol) was placed in a 100 mL three-necked flask, and 17.0 mL of tetrahydrofuran was added to completely dissolve it. Subsequently, i-PrMgCl (14.3 mmol) was slowly added dropwise to the 5-cyano-2-iodophenyl dioxaethyl phosphite solution at -30 °C / argon. After the addition was completed, the reaction solution was stirred for 40 min, and then a tetrahydrofuran solution of PCl3 (0.36 mL, 4.16 mmol) was added dropwise. After the addition was completed, the reaction solution was slowly heated to room temperature and stirred for 16 h. After the reaction was complete, the reaction solution was cooled to 0°C and quenched by adding 1M HCl, extracted with ethyl acetate (3×30 mL), washed, dried, and concentrated in vacuo to obtain a crude product, which was purified by column chromatography to obtain triphenylphosphine carbonitrile containing a phosphite group (Compound 3) (1.09 g, 42%) as a colorless solid. 1H NMR (400 MHz, CDCl3) δ: 7.57 (dd, J1=6.0 Hz, J2=1.6 Hz, 3H, ArH), 7.45 (d, J=6.0 Hz, 3H, ArH), 7.36 (d, J=1.6 Hz, 3H, ArH), 3.85 (s, 12H, CH2).

[0078] 2) Synthesis of a covalent organic framework phosphine ligand containing multiple coordination sites: Compound 3 (1.0 g, 1.5 mmol) obtained in step 1) was added to 40 mL of chloroform solution, and then 8 mL of trifluoromethanesulfonic acid was slowly added dropwise to the solution at 5°C and kept at 40°C for 2 days. After the reaction was completed, the mixture was neutralized with LiOH and stirred at room temperature for 24 h, and the yellow precipitate was collected by filtration, washed with a large amount of H2O, and then vacuum dried at 80°C for 12 h to obtain a covalent organic framework phosphine ligand P-COF3. The specific synthesis route is shown in formula (5).

[0079]

[0080] A method for preparing a heterogeneous catalyst comprises the following steps:

[0081] At 25°C and in an Ar gas atmosphere, 1.0 g of the above-prepared covalent organic framework phosphine ligand P-COF3 containing multiple coordination sites was added to a tetrahydrofuran (100 mL) solution containing 30 mg of acetylacetonato dicarbonyl rhodium and stirred for 24 h. Subsequently, the solvent was removed in vacuo at 50°C to obtain a heterogeneous catalyst (P-COF3-Rh) in which the covalent organic framework phosphine ligand containing multiple coordination sites coordinated / loaded with Rh metal components.

[0082] Application of heterogeneous catalysts in dodecene hydroformylation process

[0083] Catalyst P-COF3-Rh is suitable for the hydroformylation reaction of C6-C14 high carbon olefins to prepare C7-C15 high carbon aldehydes. Let's take dodecene as an example.

[0084] 50 mL of dodecene, 0.1 g of catalyst P-COF3-Rh and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. The carbon monoxide / hydrogen cylinder was connected and quickly heated to 160 ° C. At the same time, the system pressure was adjusted to 6 MPa, the stirring rate was 800 rpm, and maintained for 8 hours. After the reaction was completed, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid was extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 1.

[0085] Example 4

[0086] The preparation method of a covalent organic framework phosphine ligand containing multiple coordination sites comprises the following steps:

[0087] 1) Synthesis of triphenylphosphine carbonitrile containing phosphite group: 5-cyano-2-iodophenyl diisopropyl phosphite (4.0 g, 10.06 mmol) was placed in a 100 mL three-necked flask, and 17.5 mL of tetrahydrofuran was added to completely dissolve 5-cyano-2-iodophenyl diisopropyl phosphite. Subsequently, i-PrMgCl (13.6 mmol) was slowly added dropwise to the solution of 5-cyano-2-iodophenyl diisopropyl phosphite at -50 °C / argon. After the addition was completed, the reaction solution was stirred for 40 min, and then a tetrahydrofuran solution of PCl3 (0.30 ml, 4.05 mmol) was added dropwise. After the addition was completed, the reaction solution was slowly heated to room temperature and stirred for 16 h. After the reaction was completed, the reaction solution was cooled to -1 °C and quenched by adding 1M HCl, extracted with ethyl acetate (3×30 mL), washed, dried, and concentrated in vacuo to obtain a crude product, which was purified by column chromatography to obtain triphenylphosphine carbonitrile containing a phosphite group (Compound 4) (1.15 g, 41%) as a colorless solid. 1H NMR (400 MHz, CDCl3) δ: 7.54 (dd, J1=6.0 Hz, J2=1.6 Hz, 3H, ArH), 7.43 (d, J=6.0 Hz, 3H, ArH), 7.32 (d, J=1.6 Hz, 3H, ArH), 3.52-3.46 (m, 1H, CH), 2.05 (d, J=6.4 Hz, 36H, CH3).

[0088] 2) Synthesis of a covalent organic framework phosphine ligand containing multiple coordination sites: The triphenylphosphine carbonitrile containing a phosphite group obtained in step 1) (1.0 g, 1.44 mmol) was added to 40 mL of chloroform solution, and then 5 mL of trifluoromethanesulfonic acid was slowly added dropwise to the above solution at -1°C and kept at 20°C for 6 days. After the reaction was completed, the mixture was neutralized with LiOH and stirred at room temperature for 24 hours, and the yellow precipitate was collected by filtration, washed with a large amount of H2O, and then vacuum dried at 80°C for 12 hours to obtain a covalent organic framework phosphine ligand P-COF4. The specific synthesis route is shown in formula (6).

[0089]

[0090] A method for preparing a heterogeneous catalyst comprises the following steps:

[0091] At 25°C and in an Ar gas atmosphere, 1.0 g of the above-prepared covalent organic framework phosphine ligand P-COF4 containing multiple coordination sites was added to a tetrahydrofuran (100 mL) solution containing 30 mg of acetylacetonato dicarbonyl rhodium and stirred for 24 hours. Subsequently, the solvent was removed in vacuo at 50°C to obtain a heterogeneous catalyst (P-COF4-Rh) in which the covalent organic framework phosphine ligand containing multiple coordination sites coordinated / loaded with Rh metal components.

[0092] Application of heterogeneous catalysts in the hydroformylation of dodecene

[0093] P-COF1-Rh is suitable for the hydroformylation reaction of C6-C14 high carbon olefins to prepare C7-C15 high carbon aldehydes. This embodiment takes dodecene as an example.

[0094] 50 mL of dodecene, 0.1 g of catalyst P-COF1-Rh and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. The carbon monoxide / hydrogen cylinder was connected and quickly heated to 90 ° C. At the same time, the system pressure was adjusted to 0.5 MPa, the stirring rate was 800 rpm, and maintained for 18 hours. After the reaction was completed, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid was extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 1.

[0095] Example 5

[0096] The preparation method of a covalent organic framework phosphine ligand containing multiple coordination sites comprises the following steps:

[0097] 1) Synthesis of triphenylphosphine carbonitrile containing phosphite group: 5-cyano-2-iodophenyl bis(trifluoromethyl)phosphite (4.0 g, 10.23 mmol) was placed in a 100 mL three-necked flask, and 17.5 mL of tetrahydrofuran was added to completely dissolve 5-cyano-2-iodophenyl bis(trifluoromethyl)phosphite. Subsequently, i-PrMgCl (12.2 mmol) was slowly added dropwise to the 5-cyano-2-iodophenyl bis(trifluoromethyl)phosphite solution at -50 °C / argon. After the addition was completed, the reaction solution was stirred for 40 min, and then a tetrahydrofuran solution of PCl3 (0.27 ml, 3.6 mmol) was added dropwise. After the addition was completed, the reaction solution was slowly heated to room temperature and stirred for 16 h. After the reaction was complete, the reaction solution was cooled to -1°C and quenched by adding 1M HCl, extracted with ethyl acetate (3×30 mL), washed, dried, and concentrated in vacuo to obtain a crude product, which was purified by column chromatography to obtain triphenylphosphine carbonitrile containing a phosphite group (Compound 5) (1.23 g, 47%) as a colorless solid. 1H NMR (400 MHz, CDCl3) δ: 7.56 (dd, J1=6.0 Hz, J2=1.6 Hz, 3H, ArH), 7.44 (d, J=6.0 Hz, 3H, ArH), 7.35 (d, J=1.6 Hz, 3H, ArH).

[0098] 2) Synthesis of a covalent organic framework phosphine ligand containing multiple coordination sites: Compound 5 (1.0 g, 1.40 mmol) obtained in step 1) was added to 40 mL of chloroform solution, and then 5 mL of trifluoromethanesulfonic acid was slowly added dropwise to the solution at -1°C and kept at 20°C for 6 days. After the reaction was completed, the mixture was neutralized with LiOH and stirred at room temperature for 24 h, and the yellow precipitate was collected by filtration, washed with a large amount of H2O, and then vacuum dried at 80°C for 12 h to obtain a covalent organic framework phosphine ligand P-COF5. The specific synthesis route is shown in formula (7).

[0099]

[0100] A method for preparing a heterogeneous catalyst comprises the following steps:

[0101] At 25°C and in an Ar gas atmosphere, 1.0 g of the above-prepared covalent organic framework phosphine ligand P-COF4 containing multiple coordination sites was added to a tetrahydrofuran (100 mL) solution containing 30 mg of acetylacetonato dicarbonyl rhodium and stirred for 24 hours. Subsequently, the solvent was removed in vacuo at 50°C to obtain a heterogeneous catalyst (P-COF4-Rh) in which the covalent organic framework phosphine ligand containing multiple coordination sites coordinated / loaded with Rh metal components.

[0102] Application of heterogeneous catalysts in the hydroformylation of dodecene

[0103] P-COF5-Rh is suitable for the hydroformylation reaction of C6-C14 high carbon olefins to prepare C7-C15 high carbon aldehydes. We take dodecene as an example.

[0104] 50 mL of dodecene, 0.1 g of catalyst P-COF5-Rh and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. The carbon monoxide / hydrogen cylinder was connected and quickly heated to 90 ° C. At the same time, the system pressure was adjusted to 0.5 MPa, the stirring rate was 800 rpm, and maintained for 18 hours. After the reaction was completed, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid was extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 1.

[0105] Application Example 1

[0106] Catalyst separation and reuse experiment

[0107] In order to study the reusability of the Rh metal catalyst coordinated by the covalent organic framework phosphine ligand containing multiple coordination sites, the catalyst P-COF2-Rh of Example 2 was taken as an example. In a glove box filled with argon, the catalyst P-COF2-Rh was separated from the reaction solution by suction filtration to obtain the catalyst P-COF2-Rh. The separated catalyst was put into the second to tenth dodecene hydroformylation reactions without any treatment.

[0108] 50 mL of dodecene, 0.1 g of catalyst P-COF2-Rh (isolated from the reaction solution of the first reaction) and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. Connect the carbon monoxide / hydrogen cylinder, heat quickly to 130 ° C, adjust the system pressure to 3.5 MPa, stir at 800 rpm, and maintain for 10 hours. After the reaction, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction solution was extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 1.

[0109] Application Example 2

[0110] 50 mL of dodecene, 0.1 g of catalyst P-COF2-Rh (isolated from the reaction solution of the second reaction) and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. Connect the carbon monoxide / hydrogen cylinder, heat quickly to 280 ° C, adjust the system pressure to 0.5 MPa, stir at 800 rpm, and maintain for 0.5 hours. After the reaction, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction solution was extracted for treatment and then subjected to gas chromatography analysis. The data results are recorded in Table 1.

[0111] Application Example 3

[0112] 50 mL of dodecene, 0.1 g of catalyst P-COF2-Rh (isolated from the reaction solution of the third reaction) and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. Connect the carbon monoxide / hydrogen cylinder, heat quickly to 50 ° C, adjust the system pressure to 20 MPa, stir at 800 rpm, and maintain for 100 hours. After the reaction, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction solution was extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 1.

[0113] Application Example 4

[0114] 50 mL of dodecene, 0.1 g of catalyst P-COF2-Rh (isolated from the reaction solution of the fourth reaction) and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. The carbon monoxide / hydrogen cylinder was connected and quickly heated to 150 ° C. At the same time, the system pressure was adjusted to 3 MPa, the stirring rate was 800 rpm, and maintained for 50 hours. After the reaction was completed, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction solution was extracted for treatment and then subjected to gas chromatography analysis. The data results are recorded in Table 1.

[0115] Application Example 5

[0116] 50 mL of dodecene, 0.1 g of catalyst P-COF2-Rh (isolated from the reaction solution of the fifth reaction) and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. The carbon monoxide / hydrogen cylinder was connected and quickly heated to 200 ° C. At the same time, the system pressure was adjusted to 15 MPa, the stirring rate was 800 rpm, and maintained for 24 hours. After the reaction was completed, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction solution was extracted for treatment and then subjected to gas chromatography analysis. The data results are recorded in Table 1.

[0117] Application Example 6

[0118] 50 mL of dodecene, 0.1 g of catalyst P-COF2-Rh (isolated from the reaction solution of the sixth reaction) and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. Connect the carbon monoxide / hydrogen cylinder, heat quickly to 100 ° C, adjust the system pressure to 11 MPa, stir at 800 rpm, and maintain for 15 hours. After the reaction, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction solution was extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 1.

[0119] Application Example 7

[0120] 50 mL of dodecene, 0.1 g of catalyst P-COF2-Rh (isolated from the reaction solution of the 7th reaction) and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. Connect the carbon monoxide / hydrogen cylinder, heat quickly to 250 ° C, adjust the system pressure to 12 MPa, stir at 800 rpm, and maintain for 48 hours. After the reaction, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction solution was extracted for treatment and then subjected to gas chromatography analysis. The data results are recorded in Table 1.

[0121] Application Example 8

[0122] 50 mL of dodecene, 0.1 g of catalyst P-COF2-Rh (isolated from the reaction solution of the 8th reaction) and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. Connect the carbon monoxide / hydrogen cylinder, heat quickly to 90 ° C, adjust the system pressure to 1 MPa, stir at 800 rpm, and maintain for 15 hours. After the reaction, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction solution was extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 1.

[0123] Application Example 9

[0124] 50 mL of dodecene, 0.1 g of catalyst P-COF2-Rh (isolated from the reaction solution of the 9th reaction) and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. Connect the carbon monoxide / hydrogen cylinder, heat quickly to 130 ° C, adjust the system pressure to 3.5 MPa, stir at 800 rpm, and maintain for 10 hours. After the reaction, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction solution was extracted for treatment and then subjected to gas chromatography analysis. The data results are recorded in Table 1.

[0125] Comparative Example 1

[0126] 50 mL of dodecene, 0.1 g of catalyst Rh2Cl2(CO)4 (200 ppm) and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. The carbon monoxide / hydrogen cylinder was connected, and the mixture was quickly heated to 130°C. At the same time, the system pressure was adjusted to 3.5 MPa, and the stirring rate was 800 rpm, which was maintained for 10 hours. After the reaction was completed, the reactor was quickly cooled to room temperature, and the pressure was slowly released to normal pressure. The reaction solution was extracted and treated, and then subjected to gas chromatography analysis. The data results are recorded in Table 1.

[0127] Comparative Example 2

[0128] 50 mL of dodecene, 0.1 g of catalyst Rh2Cl2(CO)4 (200 ppm), triphenylphosphine (600 ppm) and 20 mL of toluene were added to a 200 mL autoclave, and then the air was replaced with N2. The carbon monoxide / hydrogen cylinder was connected and quickly heated to 130°C. At the same time, the system pressure was adjusted to 3.5 MPa, the stirring rate was 800 rpm, and maintained for 10 hours. After the reaction was completed, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction solution was extracted and treated and then subjected to gas chromatography analysis. The data results are recorded in Table 1.

[0129] In order to verify that the introduction of multiple phosphorus coordination sites has a higher catalytic performance for COF phosphine ligand-Rh catalyst, we also prepared its reference ligand COF-P-1, and prepared the corresponding phosphine-rhodium catalyst COF-P-1-Rh according to a similar method, and applied it to the hydroformylation reaction of dodecene. The specific details are as follows:

[0130] Table 1 Performance of each group of catalysts in catalytic hydroformylation of dodecene

[0131]

[0132]

[0133] As shown in Table 1, the catalysts prepared in Examples 1-3 have a dodecene conversion rate of more than 90% and a tridecane selectivity of more than 90% in the hydroformylation reaction of dodecene with CO and H2 to prepare tridecane. In particular, the catalyst P-COF2-Rh prepared in Example 2 has a dodecene conversion rate of 96.3% and a tridecane selectivity of 95.3% as a catalyst. The dodecene conversion rate and tridecane selectivity are significantly higher than those of Comparative Examples 1-2, indicating that the catalyst prepared in the present invention is useful for the hydroformylation of dodecene. In the reaction to prepare tridecanal, the conversion rate of dodecene and the selectivity of tridecanal can be improved. The catalytic performance of P-COF2-Rh is also better than that of the Rh metal catalyst COF-P-1-Rh (Example 6) coordinated / loaded with a covalent organic framework ligand having fewer coordination sites, indicating that the phosphite substituent on the covalent framework phosphine ligand containing multiple coordination sites plays a positive role. This is mainly attributed to the fact that the covalent organic framework phosphine ligand containing multiple coordination sites has more sites that can increase coordination with Rh, thereby accelerating the hydroformylation reaction of dodecene.

[0134] In addition, if Figure 1 As shown, in the 10 repeated experiments of Application Examples 1 to 9, the activity of P-COF2-Rh only slightly decreased (dodecene conversion from 96.3% to 92.9%; tridecanal selectivity from 95.3% to 91.8%), indicating that the covalent organic framework phosphine ligand-Rh catalyst containing multiple coordination sites can be recycled.

[0135] In summary, the covalent organic framework phosphine ligand-Rh catalyst containing multiple coordination sites and the structure of formula (1) can be applied to the preparation of tridecanal by the hydroformylation reaction of dodecene, and can improve the conversion rate of dodecene and the selectivity of tridecanal, and its preparation process is simple and the production cost is low. Most importantly, the covalent organic framework phosphine ligand-Rh catalyst containing multiple coordination sites can be separated from the reaction solution by a simple suction filtration operation, so as to realize the recycling of the catalyst, and repeated experimental studies have shown that the catalytic activity of the covalent organic framework phosphine ligand-Rh catalyst containing multiple coordination sites only decreases by 7.0% in 10 repeated experiments.

[0136] The catalyst comprising a covalent organic framework phosphine ligand having a structure shown in formula (2) is applied to a heterogeneous catalytic reaction of preparing isononanal by hydroformylation of isooctene, and can improve the conversion rate of isooctene and the selectivity of isononanal. The catalyst and its preparation method are shown in Examples 6 to 10, and the application examples based on the catalyst separation and reuse experiment of Example 6 are shown in Application Examples 10 to 18. The corresponding comparative examples are Comparative Examples 4 to 5.

[0137]

[0138] Example 6

[0139] The preparation method of a covalent organic framework phosphine ligand containing multiple coordination sites comprises the following steps:

[0140] 1) Synthesis of 4',4"-triphenylphosphine: 4-iodobenzonitrile (4.0 g, 17.5 mmol) was placed in a 100 mL three-necked flask, and 17.5 mL of tetrahydrofuran was added to completely dissolve 4-iodobenzonitrile. Subsequently, i-PrMgCl (18.4 mmol) was slowly added dropwise to the 4-iodobenzonitrile solution at -40 °C / argon. After the addition was complete, the reaction solution was stirred for 40 min, and then a tetrahydrofuran solution of PCl3 (0.51 ml, 5.82 mmol) was added dropwise. After the addition was complete, the reaction solution was slowly warmed to room temperature and stirred for 16 h. After the reaction was complete, the reaction solution was cooled to 0 °C and quenched by adding 1 M HCl, and extracted with ethyl acetate (3×30 mL), washed, dried, and concentrated in vacuo to obtain a crude product, which was purified by column chromatography to obtain 4,4',4"-triphenylphosphine (1.24 g, 63%) as a colorless solid. 1H NMR (400MHz, CDCl3) δ: 7.68-7.66 (m, 6H, ArH), 7.38-7.35 (m, 6H, ArH).

[0141] 2) Synthesis of compound COF-P-1: 4,4',4"-triphenylphosphine (1.0 g, 2.6 mmol) was added to 40 mL of chloroform solution, and then 8 mL of trifluoromethanesulfonic acid was slowly added dropwise to the above solution at 0°C and kept at 30°C for 4 days. After the reaction was completed, the mixture was neutralized with LiOH and stirred at room temperature for 24 h. The yellow precipitate was collected by filtration, washed with a large amount of H2O, and then vacuum dried at 80°C for 12 h to obtain the covalent organic framework phosphine ligand COF-P-1. The specific synthesis route is shown in formula (8).

[0142]

[0143] A method for preparing a heterogeneous catalyst comprises the following steps:

[0144] At 25°C and in an Ar gas atmosphere, 20 mg of acetylacetonato dicarbonyl rhodium was weighed and dissolved in 100 mL of tetrahydrofuran solvent, and 1.0 g of the covalent organic framework phosphine ligand COF-P-1 prepared above was added, and stirred for 24 hours. Subsequently, the solvent was removed in vacuo at 50°C to obtain a heterogeneous catalyst (COF-P-1-Rh) with a covalent organic framework phosphine ligand coordinated / loaded with a Rh metal component.

[0145] Application of heterogeneous catalysts in the hydroformylation of isooctene

[0146] The catalyst is suitable for the hydroformylation reaction of C6-C14 high carbon olefins to prepare C7-C15 high carbon aldehydes. This embodiment takes isooctene as an example.

[0147] Add olefin (25mL), catalyst COF-P-1-Rh (0.1g) and solvent toluene (20mL) to a 100mL autoclave, and then replace the air with N2. Connect the carbon monoxide / hydrogen cylinder, heat to 120°C, adjust the system pressure to 3.0MPa, stir at 800rpm, and maintain for 10 hours. After the reaction is completed, the reactor is quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid is extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 2.

[0148] Example 7

[0149] The preparation method of a covalent organic framework phosphine ligand containing multiple coordination sites comprises the following steps:

[0150] 1) Synthesis of 2,2',2"-trimethyl-4,4',4"-triphenylphosphine: 3-methyl-4-iodobenzonitrile (4.0 g, 17.1 mmol) was placed in a 100 mL three-necked flask, and 17.0 mL of tetrahydrofuran was added to completely dissolve 3-methyl-4-iodobenzonitrile. Subsequently, i-PrMgCl (18.0 mmol) was slowly added dropwise to the 3-methyl-4-iodobenzonitrile solution at -50 °C / argon. After the addition was complete, the reaction solution was stirred for 40 min, and then a tetrahydrofuran solution of PCl3 (0.48 mL, 5.47 mmol) was added dropwise. After the addition was complete, the reaction solution was slowly heated to room temperature and stirred for 16 h. After the reaction was completed, the reaction solution was cooled to -1 °C and quenched by adding 1M HCl, extracted with ethyl acetate (3×30 mL), washed, dried, and concentrated in vacuo to obtain a crude product, which was purified by column chromatography to obtain 2,2',2"-trimethyl-4,4',4"-triphenylphosphine (1.45 g, 70%) as a colorless solid. 1HNMR (400 MHz, CDCl3) δ: 7.62 (td, J1=6.8 Hz, J2=1.6 Hz, 3H, ArH), 7.46 (dd, J1=6.4 Hz, J2=1.6 Hz, 3H, ArH), 7.29 (dd, J1=3.6 Hz, J2=1.6 Hz, 3H, ArH), 2.33 (s, 9H, CH3).

[0151] 2) Synthesis of compound COF-P-2: 2,2',2"-trimethyl-4,4',4"-triphenylphosphine (1.0 g, 2.6 mmol) was added to 40 mL of chloroform solution, and then 8 mL of trifluoromethanesulfonic acid was slowly added dropwise to the above solution at -1°C and kept at 20°C for 6 days. After the reaction was completed, the mixture was neutralized with LiOH and stirred at room temperature for 24 h. The yellow precipitate was collected by filtration, washed with a large amount of H2O, and then vacuum dried at 80°C for 12 h to obtain the covalent organic framework phosphine ligand COF-P-2. The specific synthesis route is shown in formula (9).

[0152]

[0153] A method for preparing a heterogeneous catalyst comprises the following steps:

[0154] At 25°C and in an Ar gas atmosphere, 20 mg of acetylacetonato dicarbonyl rhodium was weighed and dissolved in 100 mL of tetrahydrofuran solvent, and 1.0 g of the covalent organic framework phosphine ligand COF-P-2 prepared above was added, and stirred for 24 hours. Subsequently, the solvent was removed in vacuo at 50°C to obtain a solid heterogeneous catalyst (COF-P-2-Rh) loaded with metal components by the covalent organic framework phosphine ligand.

[0155] Application of a heterogeneous catalyst in the hydroformylation of isooctene

[0156] The catalyst is suitable for the hydroformylation reaction of C6-C14 high carbon olefins to prepare C7-C15 high carbon aldehydes. We take isooctene as an example.

[0157] Olefin (25 mL), catalyst COF-P-2-Rh (0.1 g) and solvent toluene (20 mL) were added to a 100 mL autoclave, and then the air was replaced with N2. The carbon monoxide / hydrogen cylinder was connected and heated to 80°C. At the same time, the system pressure was adjusted to 1 MPa, the stirring rate was 800 rpm, and maintained for 15 hours. After the reaction was completed, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid was extracted and treated for gas chromatography analysis. The data results are recorded in Table 2.

[0158] Example 8

[0159] A method for preparing a covalent organic framework phosphine ligand comprises the following steps:

[0160] 1) Synthesis of 2,2',2"-triethyl-4,4',4"-triphenylphosphine: 3-ethyl-4-iodobenzonitrile (4.0 g, 15.5 mmol) was placed in a 100 mL three-necked flask, and 17.0 mL of tetrahydrofuran was added to completely dissolve 3-ethyl-4-iodobenzonitrile. Subsequently, i-PrMgCl (18.6 mmol) was slowly added dropwise to the 3-ethyl-4-iodobenzonitrile solution at -30°C / argon. After the addition was complete, the reaction solution was stirred for 40 min, and then a tetrahydrofuran solution of PCl3 (0.47 mL, 5.43 mmol) was added dropwise. After the addition was complete, the reaction solution was slowly heated to room temperature and stirred for 16 h. After the reaction was completed, the reaction solution was cooled to 0°C and quenched by adding 1M HCl, and extracted with ethyl acetate (3×30 mL), washed, dried, and concentrated in vacuo to obtain a crude product, which was purified by column chromatography to obtain 2,2',2"-triethyl-4,4',4"-triphenylphosphine (1.48 g, 68%) as a colorless solid. 1HNMR (400 MHz, CDCl3) δ: 7.66 (td, J1=6.8 Hz, J2=1.6 Hz, 3H, ArH), 7.49 (dd, J1=6.4 Hz, J2=1.6 Hz, 3H, ArH), 7.35-7.33 (m, 3H, ArH), 2.66 (q, J=5.6 Hz, 6H, CH2), 1.18 (t, J=5.2 Hz, 9H, CH3).

[0161] 2) Synthesis of compound COF-P-3: 2,2',2"-triethyl-4,4',4"-triphenylphosphine (1.0 g, 2.4 mmol) was added to 40 mL of chloroform solution, and then 8 mL of trifluoromethanesulfonic acid was slowly added dropwise to the above solution at 5°C and kept at 30°C for 4 days. After the reaction was completed, the mixture was neutralized with LiOH and stirred at room temperature for 24 h. The yellow precipitate was collected by filtration, washed with a large amount of H2O, and then vacuum dried at 80°C for 12 h to obtain the covalent organic framework phosphine ligand COF-P-3. The specific synthesis route is shown in formula (10).

[0162]

[0163] A method for preparing a heterogeneous catalyst comprises the following steps:

[0164] At 25°C and in an Ar gas atmosphere, 20 mg of acetylacetonato dicarbonyl rhodium was weighed and dissolved in 100 mL of tetrahydrofuran solvent, and 1.0 g of the covalent organic framework phosphine ligand COF-P-3 prepared above was added, and stirred for 24 hours. Subsequently, the solvent was removed in vacuo at 50°C to obtain a solid heterogeneous catalyst (COF-P-3-Rh) loaded with metal components by the covalent organic framework phosphine ligand.

[0165] Application of heterogeneous catalysts in the hydroformylation of isooctene

[0166] The catalyst is suitable for the hydroformylation reaction of C6-C14 high carbon olefins to prepare C7-C15 high carbon aldehydes. We take isooctene as an example.

[0167] Olefin (25 mL), catalyst COF-P-3-Rh (0.1 g) and solvent toluene (20 mL) were added to a 100 mL autoclave, and then the air was replaced with N2. The carbon monoxide / hydrogen cylinder was connected and quickly heated to 150°C. At the same time, the system pressure was adjusted to 5 MPa, the stirring rate was 800 rpm, and maintained for 8 hours. After the reaction was completed, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid was extracted and processed for gas chromatography analysis. The data results are recorded in Table 2.

[0168] Example 9

[0169] A method for preparing a covalent organic framework phosphine ligand comprises the following steps:

[0170] 1) Synthesis of 2,2',2"-tripropyl-4,4',4"-triphenylphosphine: 3-propyl-4-iodobenzonitrile (4.0 g, 14.7 mmol) was placed in a 100 mL three-necked flask, and 16.0 mL of tetrahydrofuran was added to completely dissolve 3-propyl-4-iodobenzonitrile. Subsequently, i-PrMgCl (17.7 mmol) was slowly added dropwise to the 3-propyl-4-iodobenzonitrile solution at -40°C / argon. After the addition was complete, the reaction solution was stirred for 40 min, and then a tetrahydrofuran solution of PCl3 (0.45 mL, 5.16 mmol) was added dropwise. After the addition was complete, the reaction solution was slowly heated to room temperature and stirred for 16 h. After the reaction was completed, the reaction solution was cooled to 0°C and quenched by adding 1M HCl, extracted with ethyl acetate (3×30 mL), washed, dried, and concentrated in vacuo to obtain a crude product, which was purified by column chromatography to obtain 2,2',2"-tripropyl-4,4',4"-triphenylphosphine (1.48 g, 65%) as a colorless solid. 1HNMR (400 MHz, CDCl3) δ: 7.65 (td, J1=6.8 Hz, J2=1.6 Hz, 3H, ArH), 7.51 (dd, J1=6.4 Hz, J2=1.6 Hz, 3H, ArH), 7.29-7.26 (m, 3H, ArH), 2.65 (t, J=5.2 Hz, 6H, CH2), 1.60-1.52 (m, 6H, CH2), 0.98 (t, J=6.0 Hz, 9H, CH3).

[0171] 2) Synthesis of compound COF-P-4: 2,2',2"-tripropyl-4,4',4"-triphenylphosphine (1.0 g, 2.6 mmol) was added to 40 mL of chloroform solution, and then 8 mL of trifluoromethanesulfonic acid was slowly added dropwise to the above solution at 0°C and kept at 30°C for 4 days. After the reaction was completed, the mixture was neutralized with LiOH and stirred at room temperature for 24 h. The yellow precipitate was collected by filtration, washed with a large amount of H2O, and then vacuum dried at 80°C for 12 h to obtain the covalent organic framework phosphine ligand COF-P-4. The specific synthesis route is shown in formula (11).

[0172]

[0173] A method for preparing a heterogeneous catalyst comprises the following steps:

[0174] At 25°C and in an Ar gas atmosphere, 20 mg of acetylacetonato dicarbonyl rhodium was weighed and dissolved in 100 mL of tetrahydrofuran solvent, and 1.0 g of the covalent organic framework phosphine ligand COF-P-4 prepared above was added, and stirred for 24 hours. Subsequently, the solvent was removed in vacuo at 50°C to obtain a solid heterogeneous catalyst (COF-P-4-Rh) loaded with metal components by the covalent organic framework phosphine ligand.

[0175] Application of heterogeneous catalysts in the hydroformylation of isooctene

[0176] The catalyst is suitable for the hydroformylation reaction of C6-C14 high carbon olefins to prepare C7-C15 high carbon aldehydes. We take isooctene as an example.

[0177] Olefin (25 mL), catalyst COF-P-4-Rh (0.1 g) and solvent toluene (20 mL) were added to a 100 mL autoclave, and then the air was replaced with N2. The carbon monoxide / hydrogen cylinder was connected and quickly heated to 50°C. At the same time, the system pressure was adjusted to 10 MPa, the stirring rate was 800 rpm, and maintained for 100 hours. After the reaction was completed, the reactor was quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid was extracted and treated for gas chromatography analysis. The data results are recorded in Table 2.

[0178] Example 10

[0179] A method for preparing a covalent organic framework phosphine ligand comprises the following steps:

[0180] 1) Synthesis of 2,2',2"-trifluoromethyl-4,4',4"-triphenylphosphine: 3-Trifluoromethyl-4-iodobenzonitrile (4.0 g, 13.5 mmol) was placed in a 100 mL three-necked flask, and 15.0 mL of tetrahydrofuran was added to completely dissolve 3-trifluoromethyl-4-iodobenzonitrile. Subsequently, i-PrMgCl (16.2 mmol) was slowly added dropwise to the 3-trifluoromethyl-4-iodobenzonitrile solution at -40 °C / argon. After the addition was complete, the reaction solution was stirred for 40 min, and then a tetrahydrofuran solution of PCl3 (0.41 mL, 4.7 mmol) was added dropwise. After the addition was complete, the reaction solution was slowly heated to room temperature and stirred for 16 h. After the reaction was completed, the reaction solution was cooled to 0°C and quenched by adding 1M HCl, extracted with ethyl acetate (3×30 mL), washed, dried, and concentrated in vacuo to obtain a crude product, which was purified by column chromatography to obtain 2,2',2"-trifluoromethyl-4,4',4"-triphenylphosphine (1.48 g, 61%) as a colorless solid. 1H NMR (400 MHz, CDCl3) δ: 7.78-7.75 (m, 6H, ArH), 7.68-7.63 (m, 6H, ArH).

[0181] 2) Synthesis of compound COF-P-5: 2,2',2"-trifluoromethyl-4,4',4"-triphenylphosphine (1.0 g, 1.85 mmol) was added to 30 mL of chloroform solution, and then 6 mL of trifluoromethanesulfonic acid was slowly added dropwise to the above solution at 0°C and kept at 30°C for 4 days. After the reaction was completed, the mixture was neutralized with LiOH and stirred at room temperature for 24 h. The yellow precipitate was collected by filtration, washed with a large amount of H2O, and then vacuum dried at 80°C for 12 h to obtain the covalent organic framework phosphine ligand COF-P-5. The specific synthesis route is shown in formula (12).

[0182]

[0183] A method for preparing a heterogeneous catalyst comprises the following steps:

[0184] At 25°C and in an Ar gas atmosphere, 20 mg of acetylacetonato dicarbonyl rhodium was weighed and dissolved in 100 mL of tetrahydrofuran solvent, and 1.0 g of the covalent organic framework phosphine ligand COF-P-5 prepared above was added, and stirred for 24 hours. Subsequently, the solvent was removed in vacuo at 50°C to obtain a solid heterogeneous catalyst (COF-P-5-Rh) loaded with metal components by the covalent organic framework phosphine ligand.

[0185] Application of heterogeneous catalysts in the hydroformylation of isooctene

[0186] The catalyst is suitable for the hydroformylation reaction of C6-C14 high carbon olefins to prepare C7-C15 high carbon aldehydes. We take isooctene as an example.

[0187] Add olefin (25mL), catalyst COF-P-5-Rh (0.1g) and solvent toluene (20mL) to a 100mL autoclave, and then replace the air with N2. Connect the carbon monoxide / hydrogen cylinder, quickly heat to 250°C, adjust the system pressure to 0.5MPa, stir at 800rpm, and maintain for 1 hour. After the reaction is completed, the reactor is quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction solution is extracted and treated for gas chromatography analysis. The data results are recorded in Table 2.

[0188] Application Example 10

[0189] Catalyst recycling experiment

[0190] In order to verify the reusability of the catalyst, the catalyst COF-P-1-Rh in Example 6 was taken as an example. The catalyst COF-P-1-Rh was separated by filtration in a glove box filled with argon, and the separated catalyst was put into the second to tenth experiments without any treatment.

[0191] Add olefin (25mL), catalyst COF-P-1-Rh (0.1g) (isolated after the first experiment) and solvent toluene (20mL) to a 100mL autoclave, and then replace the air with N2. Connect the carbon monoxide / hydrogen cylinder, quickly heat to 200°C, adjust the system pressure to 5MPa, stir at 800rpm, and maintain for 24 hours. After the reaction is completed, the autoclave is quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid is extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 2.

[0192] Application Example 11

[0193] Add olefin (25mL), catalyst COF-P-1-Rh (isolated after the second experiment) and solvent toluene (20mL) to a 100mL autoclave, and then replace the air with N2. Connect the carbon monoxide / hydrogen cylinder, quickly heat to 100°C, and adjust the system pressure to 15MPa, stirring rate 800rpm, and maintain for 50 hours. After the reaction is completed, the reactor is quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid is extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 2.

[0194] Application Example 12

[0195] Add olefin (25mL), catalyst COF-P-1-Rh (isolated after the third experiment) and solvent toluene (20mL) to a 100mL autoclave, and then replace the air with N2. Connect the carbon monoxide / hydrogen cylinder, quickly heat to 80°C, adjust the system pressure to 4MPa, stir at 800rpm, and maintain for 48 hours. After the reaction is completed, the reactor is quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid is extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 2.

[0196] Application Example 13

[0197] Add olefin (25mL), catalyst COF-P-1-Rh (isolated after the 4th experiment) and solvent toluene (20mL) to a 100mL autoclave, and then replace the air with N2. Connect the carbon monoxide / hydrogen cylinder, quickly heat to 180°C, adjust the system pressure to 3.0MPa, stir at 800rpm, and maintain for 86 hours. After the reaction is completed, the reactor is quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid is extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 2.

[0198] Application Example 14

[0199] Add olefin (25mL), catalyst COF-P-1-Rh (isolated after the 5th experiment) and solvent toluene (20mL) to a 100mL autoclave, and then replace the air with N2. Connect the carbon monoxide / hydrogen cylinder, quickly heat to 120°C, adjust the system pressure to 3.0MPa, stir at 800rpm, and maintain for 10 hours. After the reaction is completed, the reactor is quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid is extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 2.

[0200] Application Example 15

[0201] Add olefin (25mL), catalyst COF-P-1-Rh (isolated after the 6th experiment) and solvent toluene (20mL) to a 100mL autoclave, and then replace the air with N2. Connect the carbon monoxide / hydrogen cylinder, quickly heat to 120°C, adjust the system pressure to 3.0MPa, stir at 800rpm, and maintain for 10 hours. After the reaction is completed, the reactor is quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid is extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 2.

[0202] Application Example 16

[0203] Add olefin (25 mL), catalyst COF-P-1-Rh (isolated after the 7th experiment) and solvent toluene (20 mL) to a 100 mL autoclave, and then replace the air with N2. Connect the carbon monoxide / hydrogen cylinder, quickly heat to 120 ° C, adjust the system pressure to 3.0 MPa, stir at 800 rpm, and maintain for 10 hours. After the reaction is completed, the reactor is quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid is extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 2.

[0204] Application Example 17

[0205] Add olefin (25mL), catalyst COF-P-1-Rh (isolated after the 8th experiment) and solvent toluene (20mL) to a 100mL autoclave, and then replace the air with N2. Connect the carbon monoxide / hydrogen cylinder, quickly heat to 120°C, adjust the system pressure to 3.0MPa, stir at 800rpm, and maintain for 10 hours. After the reaction is completed, the reactor is quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid is extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 2.

[0206] Application Example 18

[0207] Add olefin (25mL), catalyst COF-P-1-Rh (isolated after the 9th experiment) and solvent toluene (20mL) to a 100mL autoclave, and then replace the air with N2. Connect the carbon monoxide / hydrogen cylinder, quickly heat to 120°C, adjust the system pressure to 3.0MPa, stir at 800rpm, and maintain for 10 hours. After the reaction is completed, the reactor is quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction liquid is extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 2.

[0208] Comparative Example 3

[0209] Olefin (25 mL), catalyst Rh2Cl2(CO)4 (200 ppm) and solvent toluene (20 mL) were added to a 100 mL autoclave, and then the air was replaced with N2. The carbon monoxide / hydrogen cylinder was connected, and the mixture was rapidly heated to 120°C. At the same time, the system pressure was adjusted to 3.0 MPa, and the stirring rate was 800 rpm, which was maintained for 10 hours. After the reaction was completed, the autoclave was rapidly cooled to room temperature, and the pressure was slowly released to normal pressure. The reaction solution was extracted and treated, and then subjected to gas chromatography analysis. The data results are recorded in Table 2.

[0210] Comparative Example 4

[0211] Add olefin (25mL), Rh2Cl2(CO)4 (200ppm), triphenylphosphine (600ppm) and solvent toluene (20mL) to a 100mL autoclave, and then replace the air with N2. Connect the carbon monoxide / hydrogen cylinder, quickly heat to 120°C, adjust the system pressure to 3.0MPa, stir at 800rpm, and maintain for 10 hours. After the reaction is completed, the autoclave is quickly cooled to room temperature, slowly depressurized to normal pressure, and the reaction solution is extracted for treatment and then analyzed by gas chromatography. The data results are recorded in Table 2.

[0212] Table 2 Performance of catalysts in the example for the hydroformylation of isooctene

[0213]

[0214]

[0215] According to the test results recorded in Table 2, the catalysts prepared in Examples 2, 6 to 10 have an isooctene conversion rate of more than 85% and an isononanal selectivity of more than 85% in the reaction of isooctene and CO, H2 hydroformylation to prepare isononanal. In particular, the catalyst COF-P-1-Rh prepared in Example 4 has an isooctene conversion rate of 95.1% and an isononanal selectivity of 95.6%. The isooctene conversion rate and isononanal selectivity are significantly higher than those in Comparative Examples 3 to 4, indicating that the catalyst prepared in the present invention can be used in the isooctene hydroformylation reaction to prepare isononanal, which can improve the isooctene conversion rate and isononanal selectivity. In addition, Figure 2 Combined with Application Examples 10 to 18, the research results show that the catalytic activity of COF-P-1-Rh only slightly decreased in 10 repeated experiments.

[0216] In summary, the covalent organic framework phosphine ligand-Rh catalyst provided by the present invention can be applied to the preparation of isononanal by isooctene hydroformylation reaction, can improve isooctene conversion rate and isononanal selectivity, and its preparation process is simple and the production cost is low. Most importantly, the covalent organic framework phosphine ligand-Rh catalyst can be separated from the reaction solution by a simple suction filtration operation, and the catalyst can be recycled, and repeated experimental studies have shown that the activity of the covalent organic framework phosphine ligand-Rh catalyst only decreases by about 7.4% in 10 repeated experiments.

[0217] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A covalent organic framework phosphine ligand, characterized in that: Its structural formula is shown in formula (1) or formula (2): Among them, R1 is at least one of a straight chain / branched alkyl group, a cycloalkyl group, a heterocyclic group, a heterocycloalkyl group, an aryl group, a substituted aryl group and their derivatives; R2 is at least one of a hydrogen, a straight chain / branched alkyl group, a cycloalkyl group, a heterocyclic group, a heterocycloalkyl group, an aryl group, a substituted aryl group and their derivatives.

2. The covalent organic framework phosphine ligand according to claim 1, characterized in that The R1 is at least one of a methyl group, a methine group, and an ethyl group; or the R2 is at least one of a hydrogen group, a methyl group, an ethyl group, a propyl group, and a trifluoromethyl group.

3. The method for preparing the covalent organic framework phosphine ligand according to claim 1 or 2, characterized in that: The following steps are involved: (1) iodobenzonitrile containing an active group is first reacted with isopropylmagnesium chloride and phosphorus trichloride to generate triphenylphosphine carbonitrile containing an active group; wherein the molar ratio of iodobenzonitrile containing an active group, isopropylmagnesium chloride and phosphorus trichloride is 1:1-2:0.3-0.5; (2) The triphenylphosphine nitrile containing an active group generates a covalent organic framework phosphine ligand containing multiple coordination sites under the action of trifluoromethanesulfonic acid; wherein the molar ratio of the triphenylphosphine nitrile containing an active group to the trifluoromethanesulfonic acid is 1:2-10.

4. The method for preparing a covalent organic framework phosphine ligand according to claim 3, characterized in that: In the step (1), the isopropyl magnesium chloride is added dropwise to a solution of iodobenzonitrile containing an active group, stirred, and then phosphorus trichloride is added dropwise to obtain a reaction solution, and the temperature during the dropping process is -50 to -30°C; after the dropping is completed, the reaction solution is heated to 20 to 30°C and continued to be stirred; after the reaction is completed, the reaction solution is cooled and hydrochloric acid is added to quench, and then extraction, washing, drying, and vacuum concentration are performed in sequence to obtain a crude product, and after purification, a solid triphenylphosphine carbonitrile containing an active group is obtained; And / or, in the step (2), the triphenylphosphine cyanide containing an active group is added to a solvent to prepare a solution, trifluoromethanesulfonic acid is added dropwise to the solution at -1 to 5°C, and the solution is kept at 20 to 40°C for 2 to 6 days to obtain a mixture; after the reaction is completed, the mixture is neutralized with lithium hydroxide and stirred at 20 to 30°C, filtered, and the precipitate is collected, washed, and then dried to obtain a covalent organic framework phosphine ligand.

5. A heterogeneous catalyst, characterized in that The invention comprises the covalent organic framework phosphine ligand as claimed in claim 1 or 2 and a metal active component loaded on the covalent organic framework phosphine ligand.

6. The heterogeneous catalyst according to claim 5, characterized in that The metal active component is rhodium.

7. Use of the heterogeneous catalyst according to claim 5 or 6 in the preparation of high carbon aldehydes.

8. The use according to claim 7, characterized in that The application is to prepare tridecanal by using dodecene, carbon monoxide and hydrogen under the action of a heterogeneous catalyst; And / or, the amount of the heterogeneous catalyst added is 0.05% to 10% of the mass of dodecene; And / or, the reaction parameters are as follows (Ⅰ) to (Ⅲ): (I) The reaction temperature is 50 to 280°C; (II) The reaction pressure is 0.5 to 20 MPa; (III) The reaction time is 0.5 to 100 hours.

9. The use according to claim 7, characterized in that The application is to prepare isononanal by isooctene hydroformylation reaction under the action of a heterogeneous catalyst using isooctene, carbon monoxide and hydrogen; And / or, the amount of the heterogeneous catalyst added is 0.05% to 10% of the mass of isooctene; And / or, the reaction parameters are as follows (Ⅰ) to (Ⅲ): (I) The reaction temperature is 50 to 250°C; (II) The reaction pressure is 0.5 to 10 MPa; (III) The reaction time is 1 to 100 hours.

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