A P-containing porous organic polymer self-supported heterogeneous catalyst and its preparation and application

Abstract

The present invention discloses a method for preparing a P-containing porous organic polymer self-supported heterogeneous catalyst with adjustable structure and performance, wherein one or more metals Rh, Ru, Ir, Co, and Pd are used as active components in the heterogeneous catalyst, and a phosphine-containing porous organic polymer with a multi-level pore structure is used as a carrier, and the phosphine-containing organic polymer is polymerized by vinyl-functionalized triaryl phosphine. This type of coordination bond type heterogeneous catalyst is suitable for fixed bed, slurry bed, bubbling bed, trickle bed and other reactors. The heterogeneous catalyst provided by the present invention has the characteristics of adjustable structure and catalytic performance, and the catalyst has good stability and is easy to separate and recover.

Description

Technical Field

[0001] The invention belongs to the field of heterogeneous catalysis and fine chemical industry, and specifically relates to a type of phosphine-containing porous organic polymer supported catalyst and a preparation method thereof. Background Art

[0002] In recent years, porous organic polymers have been widely used in gas storage, energy storage, catalysis and other fields due to their high specific surface area, multi-level pore structure and good thermal stability. As a representative of porous organic polymers, porous organic ligands have great application potential in the field of heterogeneous catalysis.

[0003] By modifying the structure of homogeneous organic ligands and introducing vinyl groups into ligand molecules, porous organic ligands prepared by solvent thermal polymerization have high specific surface area, multi-level pore structure, excellent thermal stability and high density of coordinated atoms exposed in the polymer skeleton, all of which make them widely used in the field of heterogeneous catalysis. As the most classic organic ligand, triphenylphosphine is of great significance in the field of heterogeneous catalysis.

[0004] Triphenylphosphine is a commonly used ligand in organic synthesis and industrial production. The preparation of porous organic polymers by solvent thermal polymerization after vinylation of triphenylphosphine, and then loading active metal precursors to prepare catalysts is an emerging research point in recent years. However, the structure and properties of traditional triphenylphosphine polymers are fixed, and the catalytic performance can only be regulated by changing the loading amount or doping additives. Summary of the invention

[0005] In order to solve the above problems, the purpose of the present invention is to provide a triarylphosphine polymer supported catalyst with large differences in catalytic performance under the same conditions and use it in catalytic reactions.

[0006] The technical solution of the present invention is:

[0007] A phosphine-containing organic polymer supported catalyst, with one, two or three of metals Rh, Co, Ir, Pd or Ru as active components, triphenylphosphine organic polymer as carrier, the metal loading amount in the catalyst is 0.1-5wt%, and the polymer is prepared by solvent thermal polymerization of vinylated triphenylphosphine polymer.

[0008] The olefin group is preferably a vinyl group, and the monodentate organic phosphine ligand containing an olefin group is a triaryl phosphine ligand containing a vinyl group.

[0009] The organic polymer carrier has a multi-level pore structure and a specific surface area of ​​100 to 800 m 2 / g, containing both mesopores and micropores, with a pore volume of 0.1 to 4.0 cm 3 / g, and the pore size distribution is between 0.2 and 20.0 nm.

[0010] The catalyst is prepared by mixing triphenylphosphines with different vinyl positions in different proportions, using a solvent thermal polymerization method, in which a free radical initiator initiates a polymerization reaction of olefin groups in an organic phosphine ligand to generate a phosphine-containing organic polymer with a multi-level pore structure as a carrier, stirring the precursor of an active component and the carrier in an organic solvent, and forming multiple coordination bonds between the active component and the exposed P in the phosphine-containing organic polymer carrier. After evaporating the volatile solvent, a series of catalysts with different performances are obtained.

[0011] The preparation method of the heterogeneous catalyst is:

[0012] a) adding a vinylated triarylphosphine ligand and a free radical initiator to an organic solvent at 0 to 50° C. in an inert gas argon atmosphere, mixing, and stirring the mixture for 0.1 to 10 hours, preferably in the range of 0.5 to 5 hours;

[0013] b) transferring the mixed solution obtained in step a) into a synthesis autoclave, and performing a polymerization reaction by a solvent thermal polymerization method at 80 to 200° C. in an inert gas atmosphere, and standing for 10 to 72 hours, preferably for 12 to 48 hours, to obtain a triphenylphosphine organic polymer;

[0014] c) removing the solvent from the polymer obtained in step b) at room temperature to obtain a triaryl phosphine polymer containing exposed P and having a multi-level pore structure, which is the carrier of the heterogeneous catalyst;

[0015] d) adding the organic polymer carrier obtained in step c) to a solvent containing an active component precursor at 0-50° C. under an inert gas atmosphere, stirring for 1-48 hours, preferably 12-24 hours, and then removing the organic solvent to obtain a heterogeneous catalyst.

[0016] The organic solvent described in step a) is one or more of benzene, toluene, N,N-dimethylformamide, tetrahydrofuran, methanol, ethanol, dichloromethane or chloroform; the free radical initiator is one or more of cyclohexanone peroxide, dibenzoyl peroxide, tert-butyl hydroperoxide, azobisisobutyronitrile or azobisisoheptanenitrile.

[0017] The molar ratio of the triaryl phosphine ligand to the free radical initiator in step a) is 300:1 to 10:1, and the concentration of the triaryl phosphine ligand in the organic solvent before polymerization into the triphenylphosphine polymer is in the range of 0.01-1000 g / L.

[0018]

[0019] The solvent in step d) is one or more of water, benzene, toluene, tetrahydrofuran, methanol, ethanol, dichloromethane or chloroform, and the active component is one or more of Rh, Co, Ir, Pd, and Ru, wherein the precursor of Rh is Rh(CH3COO)2, RhH(CO)(PPh3)3, Rh(CO) 2( The precursor of Co is one or more of Co(CH3COO)2, Co(CO)2(acac), Co(acac)2, CoCl2; the precursor of Ir is one or more of Ir(CO)3(acac), Ir(CH3COO)3, Ir(acac)3, IrCl4; the precursor of Pd is one or more of PdCl2, Pd(CH3COO)2, Pd(acac)2; the precursor of Ru is RuCl3. The metal loading range in the catalyst is 0.1-5wt%.

[0020] The inert gas described in the above content is one or more of nitrogen, argon and helium.

[0021] Reaction principle of the present invention:

[0022] The present invention introduces a vinyl group and a group with different electrical properties into the benzene ring of a typical monodentate phosphine ligand such as triphenylphosphine, that is, a monodentate organic phosphine ligand containing a vinyl group and a group with different electrical properties is used as a polymerization monomer, and a solvent thermal polymerization method is used in an autoclave to polymerize an organic polymer with a high surface area and a multi-level pore structure. Since a large number of Ps containing lone pairs of electrons are exposed in the skeleton of the organic polymer, it can be used as a catalyst carrier to form multiple coordination bonds with the empty orbits of active transition metal ions, thereby forming catalytic active sites. In the catalyst, the organic phosphine polymer has the dual functions of a carrier and a ligand at the same time, and the active metal component is highly dispersed in the carrier to form multiple coordination bonds with the high-concentration exposed P. The active metal component is highly dispersed in the organic phosphine polymer carrier in the form of a single atom, which greatly improves the utilization efficiency of the metal. In addition, the active component is not easy to be lost, the catalyst has a long service life, and the phosphine ligand in the skeleton has a significant stereo effect. The prepared catalyst can significantly improve the stereoselectivity of the product.

[0023] The catalyst organic polymer carrier skeleton provided by the present invention contains P, and the organic polymer has the dual functions of a ligand and a carrier; the active metal component can be dispersed in the organic polymer carrier with a large surface area and a multi-level pore structure in the form of a single atom or an ion, which greatly improves the metal utilization efficiency. The monophosphine ligand structural unit in the carrier organic phosphine polymer skeleton enables the polymer to have a high P concentration, and it is easy to form multiple coordination bonds with the active metal component. The coordination bonds have a strong chemical bonding ability, so that the active component is not easy to lose.

[0024] The beneficial effects of the present invention are:

[0025] The multiphase catalyst skeleton of the present invention contains a monodentate organic phosphine ligand structural unit, wherein there is a relatively high exposed P on the surface of the polymer, and the active metal atoms or ions form multiple coordination bonds with the exposed P on the polymer, and the active components are not easy to be lost. The active components of the catalyst are Rh, Co, Ir, Pd or Ru. Such catalysts have high stereoselectivity, and the polymer has a high specific surface area multi-level pore structure and has the dual functions of a carrier and a ligand. The active metal components may be highly dispersed in the pores or on the surface of the organic phosphine polymer carrier in the form of single atoms, thereby improving the utilization efficiency of the metal components.

[0026] The active centers of the polytype catalyst described in the present invention are triarylphosphine and metal precursors. The catalysts prepared by self-polymerizing vinyl triarylphosphine monomers with different electrical groups exhibit different catalytic properties under the same reaction conditions and loading amounts.

[0027] This type of coordination bond type multiphase catalyst is suitable for reaction processes such as autoclave, fixed bed, slurry bed, bubbling bed and trickle bed. The preparation method of the triaryl phosphine polymer supported catalyst provided by the present invention can greatly regulate the structure and catalytic performance of the catalyst, providing technical support for its application under different conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The carrier used in the comparative example

[0029] Figure 2 The synthetic route of this type of catalyst is shown in the figure.

[0030] Figure 3 Physical adsorption curves and pore size distribution diagrams of catalysts with different structures.

[0031] Figure 4 For L1, L2 and L3 ligands 1 H, 13 C and 31 P NMR spectrum: (a) L1 1 H NMR spectrum; (b) L1 13 C NMR spectrum; (c) L1 31 P NMR spectrum; (d) L2 1 H NMR spectrum; (e) L2 13 C NMR spectrum; (f) L2 31 P NMR spectrum; (g) L3 1 H NMR spectrum; (h) L3 13 C NMR spectrum; (i) L331 P NMR spectrum.

[0032] Taking L1 as an example, the synthesis process of the ligand monomer is as follows: 50mmol of triphenylmethylphosphonium bromide is mixed with 100mL of ultra-dry tetrahydrofuran, stirred at -20°C under an argon atmosphere, and then 55mmol of n-butyl lithium solution is slowly dripped in until the reaction is complete. 50mmol of 2-bromo-3-fluorobenzaldehyde is dissolved in 50ml of ultra-dry tetrahydrofuran and slowly dripped into the former. After the dripping is complete, the reaction is carried out at room temperature and the reaction progress is monitored by thin layer chromatography until it is complete. Then, 2-bromo-3-fluorostyrene is obtained by separation and purification by column chromatography.

[0033] 51mmol magnesium chips and 2 iodine grains were placed in a flask. Under an argon atmosphere, 50mmol 2-bromo-3-fluorostyrene was dissolved in 50mL ultra-dry tetrahydrofuran and slowly added dropwise. After the reaction was complete, 16mmol phosphine trichloride was dissolved in 30mL ultra-dry tetrahydrofuran and slowly added dropwise at -10°C. The reaction progress was monitored by thin layer chromatography until it was complete. The reaction was then quenched with a saturated ammonium chloride solution, the organic phase was extracted twice with ethyl acetate, the organic phases were combined, and separated and purified by column chromatography to obtain L1.

[0034] The preparation process conditions of L2 are the same as those of L1, except that 2-bromo-3-fluorobenzaldehyde is replaced by 2-bromo-3-methylbenzaldehyde; the preparation process conditions of L3 are the same as those of L1, except that 2-bromo-3-fluorobenzaldehyde is replaced by 2-bromo-3-methoxybenzaldehyde. DETAILED DESCRIPTION

[0035] The following examples are provided to better illustrate the present invention, but are not intended to limit the scope of the present invention.

[0036] Example 1

[0037] At room temperature and inert gas argon protection atmosphere, add 10.0 grams of L1 ligand, 1.0 grams of free radical initiator azobisisobutyronitrile to the above solution and stir for 2 hours. Move the stirred solution to an autoclave and polymerize it for 24 hours at 100°C and inert gas argon protection atmosphere by solvent thermal polymerization. After the above-mentioned polymerization solution is cooled to room temperature, the solvent is vacuumed away at room temperature to obtain an organic phosphine self-polymerized self-polymer carrier obtained by self-polymerization of L1 monomer. Weigh 6.28 mg of acetylacetonato dicarbonyl rhodium and dissolve it in 100.0 mL of tetrahydrofuran solvent, add 1.0 grams of organic polymer carrier obtained by self-polymerization of L1 monomer, stir the mixture at room temperature and inert gas protection atmosphere for 24 hours, and then vacuum remove the solvent at room temperature to obtain a multiphase catalyst for octene hydroformylation.

[0038] Example 2

[0039] In Example 2, the catalyst synthesis process is the same as that of Example 1 except that 0.1 g of azobisisobutyronitrile, a free radical initiator, is weighed instead of 1.0 g of azobisisobutyronitrile, a free radical initiator.

[0040] Example 3

[0041] In Example 3, except that 50.0 ml of tetrahydrofuran solvent was used instead of 100.0 ml of tetrahydrofuran solvent, the rest of the catalyst synthesis process was the same as that of Example 1.

[0042] Example 4

[0043] In Example 4, except that 100.0 ml of dichloromethane solvent was used instead of 100.0 ml of tetrahydrofuran solvent, the rest of the catalyst synthesis process was the same as that of Example 1.

[0044] Example 5

[0045] In Example 5, except that the polymerization temperature of 120° C. was used instead of 100° C., the rest of the catalyst synthesis process was the same as that of Example 1.

[0046] Example 6

[0047] In Example 6, except that the polymerization time was 12 h instead of 24 h, the rest of the catalyst synthesis process was the same as that of Example 1.

[0048] Example 7

[0049] In Example 7, except that the L2 monomer is replaced by L1, the rest of the catalyst synthesis process is the same as that of Example 1.

[0050] Example 8

[0051] In Example 8, except that the L3 monomer is replaced by L1, the rest of the catalyst synthesis process is the same as that of Example 1.

[0052] Example 9

[0053] In Example 9, 28.2 mg of acetylacetonato dicarbonyl cobalt was weighed to replace acetylacetonato dicarbonyl rhodium and dissolved in 10.0 ml of tetrahydrofuran solvent. The rest of the catalyst synthesis process was the same as that of Example 1.

[0054] Example 10

[0055] In Example 10, 4.1 mg of iridium acetylacetonate carbonyl was weighed to replace rhodium acetylacetonate carbonyl and dissolved in 10.0 ml of tetrahydrofuran solvent. The rest of the catalyst synthesis process was the same as that of Example 1.

[0056] Embodiment 11

[0057] In Example 11, 12.6 mg of acetylacetonato dicarbonyl rhodium was weighed and dissolved in 10.0 ml of tetrahydrofuran solvent. The rest of the catalyst synthesis process was the same as that of Example 1.

[0058] Example 12

[0059] In Example 12, 25.2 mg of acetylacetonato dicarbonyl rhodium was weighed and dissolved in 10.0 ml of tetrahydrofuran solvent. The rest of the catalyst synthesis process was the same as that of Example 1.

[0060] Comparative Example 1

[0061] In Comparative Example 1, the carrier was replaced with p-3vPPh3-POL, and the rest of the catalyst synthesis process was the same as that of Example 1.

[0062] Comparative Example 2

[0063] In Comparative Example 2, the carrier was replaced with m-3vPPh3-POL, and the rest of the catalyst synthesis process was the same as that of Example 1.

[0064] Comparative Example 3

[0065] In Comparative Example 3, the carrier was replaced with o-3vPPh3-POL, and the rest of the catalyst synthesis process was the same as that of Example 1.

[0066] 0.3 g of the catalyst prepared above was loaded into a fixed bed reactor, and quartz sand was added at both ends. A reaction mixture (H2:CO = 1:1) and liquid raw material 1-octene were introduced at 120°C, 3.0 MPa, and a reaction mixture space velocity of 1000 h -1 The hydroformylation reaction was carried out under the following conditions.

[0067] The reaction was collected in a collection tank. The obtained product was analyzed by HP-7890N gas chromatography equipped with HP-5 capillary column and FID detector, using n-butanol as internal standard. After water absorption, the reaction tail gas was analyzed online by HP-7890N gas chromatography equipped with Porapak-QS column and TCD detector. The reaction results are listed in Table 1.

[0068] Table 1 Specific surface area of ​​catalysts synthesized in Examples 1-12 and octene reaction data

[0069]

[0070] * Experimental conditions: catalyst 0.3g (1.0mL), 120℃, 3MPa, reaction gas (CO:H2=1:1 volume ratio), space velocity 1000h -1 , substrate is 1-octene, liquid flow rate is 1.2h -1When calculating TOF, all metals are considered to be active sites and the reaction is carried out in a fixed bed reactor.

Claims

1. A P-containing organic polymer supported catalyst, characterized in that: The catalyst uses one or more metals, such as Rh, Ir and Co, as active components, and a phosphine-containing porous organic polymer as a carrier, and the metal loading range of the catalyst is 0.1-5wt%; The phosphine-containing porous organic polymer is prepared by solvothermal polymerization of vinyl-functionalized triarylphosphine ligand L1. The vinyl-functionalized triarylphosphine ligand L1 is shown below: 。 2. The supported catalyst according to claim 1, characterized in that: The metal loading in the catalyst ranges from 0.2 to 1.0 wt%.

3. The supported catalyst according to claim 1, characterized in that: The phosphine-containing porous organic polymer carrier has a multi-level pore structure and a specific surface area of ​​100-800m 2 / g, containing both mesopores and micropores, with the mesopore pore size distribution ranging from 2 to 20 nm, the micropore pore size distribution ranging from 0.2 to less than 2.0 nm, and the pore volume of 0.1-4.0 cm 3 / g, the pore size distribution is 0.2-20.0nm, and the mesopore volume accounts for 30-99% of the total pore volume of mesopores and micropores.

4. A method for preparing a supported catalyst according to any one of claims 1 to 3, characterized in that: The vinyl-functionalized triaryl phosphine ligand L1 adopts a solvent thermal polymerization method, and the olefin group in the ligand is polymerized by a free radical initiator to generate a phosphine-containing porous organic polymer carrier. The precursor of the active component and the carrier are stirred in an organic solvent, and the active component forms multiple coordination bonds with the exposed P in the phosphine-containing porous organic polymer carrier. After removing the solvent, a supported catalyst is obtained.

5. The method for preparing a supported catalyst according to claim 4, wherein: a) adding a desired proportion of vinyl-functionalized triarylphosphine ligand L1 and a free radical initiator to an organic solvent at 0-50° C. and in an inert gas atmosphere, and stirring the mixture for 0.1-10 hours after mixing; b) transferring the mixed solution obtained in step a) into a synthesis autoclave, and allowing to stand for 10-72 hours at 80-200° C. in an inert gas atmosphere to perform a solvent thermal polymerization reaction to obtain a phosphine-containing porous organic polymer; c) removing the solvent from the polymer obtained in step b) at room temperature to obtain a porous organic polymer containing P, i.e., the carrier of the supported catalyst; d) adding the support obtained in step c) to a solvent containing an active component precursor at 0-50° C. under an inert gas atmosphere, stirring for 1-48 hours, and then removing the organic solvent under vacuum to obtain a supported catalyst.

6. The method for preparing a supported catalyst according to claim 5, wherein: The stirring time of step a) is 0.5-5 hours, the temperature of step b) is 100-120° C., the polymerization time is 12-48 hours, and the stirring time of step d) is 12-24 hours.

7. The preparation method according to claim 5, characterized in that: The organic solvent described in step a) is benzene, toluene, N , N - one or more of dimethylformamide, tetrahydrofuran, methanol, ethanol, dichloromethane or chloroform; the free radical initiator is one or more of cyclohexanone peroxide, dibenzoyl peroxide, tert-butyl hydroperoxide, azobisisobutyronitrile or azobisisoheptanenitrile.

8. The preparation method according to claim 5 or 7, characterized in that: The molar ratio of the vinyl-functionalized triaryl phosphine ligand L1 to the free radical initiator in step a) is 300:1-10:1, and the concentration of the vinyl-functionalized triaryl phosphine ligand L1 in the organic solvent is in the range of 0.01-1000 g / L before polymerization into the porous organic polymer.

9. The preparation method according to claim 5, characterized in that: The solvent described in step d) is water, benzene, toluene, N , N - one or more of dimethylformamide, tetrahydrofuran, methanol, ethanol, dichloromethane or chloroform, the active component is one or more of Rh, Co, Ir, wherein the precursor of Rh is Rh(CH3COO)2, RhH(CO)(PPh3)3, Rh(CO) 2( acac), RhCl3; the precursor of Co is one or more of Co(CH3COO)2, Co(CO)2(acac), Co (acac)2, CoCl2; the precursor of Ir is one or more of Ir(CO)3(acac), Ir(CH3COO)3, Ir(acac)3, IrCl4.

10. Use of the supported catalyst according to any one of claims 1 to 3 in catalyzing olefin hydroformylation reaction.

Images