Iridium-based catalyst, its preparation method, and hydroformylation method

Abstract

An iridium-based catalyst is provided. The iridium catalyst has the following chemical structural formula: In the formula, Ph is a phenyl group, R is a methyl group or an ethyl group, and X is CH3CO2, NO3, The present invention is based on the prior art. Replacing the titanium-based catalyst with an iridium-based catalyst reduces the cost of the reaction and Improve production volume. [Case 1] TIFF2024538219000007.tif1314

Description

Technical Field

[0001] The present invention relates to the field of formylation reactions, and particularly to iridium-based catalysts and their preparation methods, and hydroformylation methods.

Background Art

[0002] Butyraldehyde and octanol are bulk chemical industry raw materials with a wide range of applications. Currently, industrially synthesized butanol is mainly prepared by subjecting olefins to a hydroformylation reaction to obtain n-butylaldehyde and isobutylaldehyde, and then performing subsequent reactions using these as raw materials. The hydroformylation reaction of olefins is an important step in the synthesis of butanol.

[0003] Regarding the synthesis of n-butylaldehyde and isobutylaldehyde by hydroformylation of olefins, numerous patents have been disclosed so far. In these patents and current industrial methods, generally, catalysts based on rhodium metal are employed. For example, Patent Document 1, Patent Document 2, and Patent Document 3 use triphenylphosphine-rhodium as the catalyst. Patent Document 4 uses cyclooctadieneacetic acid-rhodium as the catalyst. Patent Document 5 uses 6,6'-((3,3'-di-tert-butyl-5,5'-dimethoxy-[1,1'-biphenyl]-2, bis(oxy)) dibenzo[d,f][1,3,2] dioxaphosphepine-rhodium as the catalyst. Patent Document 6 uses acetylmorpholine-rhodium as the catalyst. Patent Document 7 uses acetic acid-rhodium as the catalyst. Patent Document 8 uses tris(2,4-di-tert-butylphenyl) phosphite-rhodium as the catalyst. Rhodium is used. Patent Document 9 uses long-chain carboxylic acid-rhodium in the catalyst. Patent Document 10 uses acetylacetonate carbonyl-rhodium in the catalyst. Patent Document 11 uses hydrido carbonyl-tris(triphenylphosphine)-rhodium in the catalyst. Patent Document 12 uses rhodium(II) acetate + tris(3-sulfonatophenyl) phosphine sodium salt hydrate in the catalyst.

[0004] In addition to the above patents, catalysts based on rhodium metal are also commonly used in published papers. For example, Non-Patent Document 1 uses a heterocyclic phosphorus ligand-rhodium in the catalyst and obtains an n-butylaldehyde / isobutylaldehyde ratio of up to 2.6. Non-Patent Document 2 uses an N-Triphos ligand-rhodium in the catalyst and obtains an n-butylaldehyde / isobutylaldehyde ratio of up to 2.3. Non-Patent Document 3 uses hydrido carbonyl-tris(triphenylphosphine)-rhodium in the catalyst and obtains an n-butylaldehyde / isobutylaldehyde ratio of up to 12.7. Non-Patent Document 4 uses a porphyrin-modified triphenylphosphine ligand-rhodium in the catalyst and obtains an n-butylaldehyde / isobutylaldehyde ratio of up to 2.3.

[0005] Although rhodium metal can be recycled many times in the hydroformylation reaction of olefins, slow losses and deactivation in the reaction process are inevitable. The international price of rhodium metal is rising rapidly, and accordingly, the catalyst cost in the production process is also rising rapidly. In addition, the value of the n-butylaldehyde / isobutylaldehyde ratio is low, which is of low value in the production process. ​​​​​​​​​​​A large amount of isobutyraldehyde with a low value was generated.

[0006] The present invention was submitted in view of this.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Patent Document 9

Patent Document 10

Patent Document 11

Patent Document 12

Non-Patent Documents

[0008]

Non-Patent Document 1

Non-Patent Document 2

[0009] The first object of the present invention is to provide an iridium-based catalyst. The iridium-based catalyst used in the present invention is less expensive than conventional iridium-based catalysts, and the production cost is significantly reduced.

[0010] The second object of the present invention is to provide a method for preparing an iridium-based catalyst. The preparation method has mild reaction conditions, significantly reduced energy consumption, and the catalytic action of the prepared catalyst is even more excellent than that of conventional catalysts.

[0011] The third object of the present invention is to provide a method for hydroformylating olefins using an iridium-based catalyst. The method for hydroformylating olefins in the present invention performs a catalytic reaction using the above-mentioned catalyst, so that not only the reaction temperature is low and the reaction conditions are mild, but also the selectivity of the target product is significantly improved. [Means for Solving the Problems]

[0012] To achieve the above object of the present invention, the following technical solutions are used.

[0013] The present invention provides an iridium-based catalyst, and the chemical structural formula of the iridium-based catalyst is as follows. ​​​​​​​​

[0014] [Chem.]

[0015] In the formula, Ph is a phenyl group, R is a methyl group or an ethyl group, and X is one or more of CH3CO2, NO 3, Cl, BF4, PF6, and SbF6. The Chinese name of the iridium-based catalyst is 4,5-bis(diphenylphosphino)-9,9- -iridium Dialkylxanthene -ium catalyst, and the abbreviation is POP(R)-Ir-X.

[0016] The present invention further provides a method for preparing an iridium-based catalyst. It includes the following steps.

[0017] 4,5-bis(diphenylphosphino)-9,9- Dialkylxanthene , a solvent and iridium compound are mixed and stirred, and then the temperature is raised and stirred to obtain an iridium-based catalyst. Here, tetrahydrofuran is selected as the solvent, cyclooctadiene iridium chloride is selected as the iridium compound, and 4,5-bis(diphenylphosphino)- 9,9- Dialkylxanthene and cyclooctadiene iridium chloride are reacted at a molar ratio of 2:1 to obtain the iridium-based catalyst POP(R)-Ir-X.

[0018] Preferably, the mixing and stirring time is 1.5 h to 3 h, preferably 2 h.

[0019] Preferably, during the temperature raising and stirring, the temperature is raised to 40 to 60 °C, preferably 50 °C and then stirred for 1.5 h to 3 h, preferably 2 h.

[0020] Preferably, when X in the iridium-based catalyst is CH3CO2, NO3, BF4, PF6, SbF 6, first, the temperature is raised and stirred to obtain the substitution target, and then a compound containing an X group is added to the substitution target object for substitution.

[0021] The present invention further provides a method for hydroformylating olefins with an iridium-based catalyst. It includes the following steps.

[0022] Under the condition that the above catalyst exists, an olefin, carbon monoxide, and hydrogen are used as raw materials for a catalytic reaction. Before the reaction, the catalyst needs to be dissolved in n-butyl aldehyde, isobutyl aldehyde, toluene ene or tetrahydrofuran.

[0023] Preferably, the reaction temperature of the catalytic reaction is 70 to 120 °C, preferably 80 °C to 110 °C. There is.

[0024] Preferably, the reaction time of the catalytic reaction is 6 to 9 h, preferably 8 h. The reaction time does not need to be too long, and the target product with a relatively high yield can be obtained with a relatively short reaction time.

[0025] Preferably, the reaction pressure of the catalytic reaction is 0.5 MPa to 3.0 MPa, preferably 1.0 MPa to 2.0 MPa.

[0026] Preferably, the partial pressure ratio of olefin to carbon monoxide is 10:1 to 1:10, preferably 5 :1 to 1:5.

[0027] Preferably, the partial pressure ratio of olefin to hydrogen is 10:1 to 1:10, preferably 5:1 to 1:5.

[0028] Preferably, the catalyst dosage is 0.005 wt% to 2.0 wt% of the solvent amount, preferably 0. It is 0.5 wt% to 1.0%.

Advantages of the Invention

[0029] The iridium-based catalyst adopted by the present invention uses propylene, carbon monoxide, and hydrogen as raw materials to perform hydroformylation to prepare n-butylaldehyde and isobutylaldehyde. Compared with the conventional rhodium-based catalyst, in the case of rhodium metal, the slow outflow and deactivation in the reaction are inevitable, which will inevitably affect not only the conversion ratio and selectivity of the reaction, but also the price of rhodium metal has been rising rapidly. However, the iridium-based catalyst adopted by the present invention has a low price, mild preparation conditions and reaction conditions for hydroformylation, and the effect of preparing n-butylaldehyde and isobutylaldehyde is better.

Brief Description of the Drawings

[0030] By reading the following detailed description of the preferred embodiments, those skilled in the art will clearly understand various other advantages and benefits. The drawings are only used for the purpose of showing the preferred embodiments and are not considered to limit the present invention. Throughout the drawings, the same members are denoted by the same reference numerals.

[0031]

Figure 1

Figure 2

Modes for Carrying Out the Invention

[0032] Hereinafter, the embodiments of the present invention will be described in detail based on examples. Those skilled in the art will understand that the following examples This is only for explaining the present invention and should not be regarded as limiting the scope of the present invention. It will be understood that for those in which specific conditions are not specified in the examples, the operations were carried out according to conventional conditions or the conditions recommended by the manufacturer. For those reagents or equipment whose manufacturers were not specified, all were common products that could be purchased on the market.

Examples

[0033] The preparation method of the iridium-based catalyst is as follows.

[0034] Synthesis of POP(CH3)-Ir-Cl: In a 250 ml reaction flask under a nitrogen atmosphere, 100 ml of tetrahydrofuran, 5.0 g of cyclooctadiene iridium chloride, and 8.6 g of 4,5-bis(diphenylphosphino)-9,9- were added, and after stirring at room temperature for 2 hours for reaction, the temperature was raised to 50 °C and stirred for 2 hours for reaction. The solvent was evaporated to dryness, and the obtained solid was washed twice with 20 ml of n-hexane. After drying, 11.9 g of POP(CH3)-Ir-Cl was obtained. Dialkylxanthene

Examples

[0035] The specific operation steps are the same as those in Example 1, but the difference is that the mixing and stirring time is 1.5 h, the temperature for heating and stirring is 40 °C, and the stirring time is 1.5 h. Finally, 1 1.4 g of POP(CH3)-Ir-Cl was obtained.

Examples

[0036] The specific operation steps are the same as those in Example 1, but the difference is that the mixing and stirring time is 3 h and the temperature for heating and stirring is 60 °C, and the stirring time is 3 h. Finally, 11.5 g The POP(CH3)-Ir-Cl was obtained.

Example

[0037] Synthesis of POP(CH3)-Ir-NO3: In a 250 ml reaction flask, 150 ml of tetrahydrofuran, 5.0 g of POP(CH3)-Ir-Cl obtained in Examples 1 to 3, 0.92 g of silver nitrate, and 20 ml of water were added. The mixture was stirred under light shielding at room temperature for 6 hours to react, and the insoluble matter was filtered. The solvent was evaporated to dryness, and the obtained solid was washed twice with 20 ml of n-hexane. After drying, 4.5 g of POP(CH3)-Ir-NO3 was obtained.

Example

[0038] Synthesis of POP(CH3)-Ir-CH3CO2: In a 250 ml reaction flask, 150 ml of tetrahydrofuran, 5.0 g of POP(CH3)-Ir-Cl obtained in Examples 1 to 3, 0.90 g of silver nitrate, and 20 ml of water were added. The mixture was stirred under light shielding at room temperature for 6 hours to react, and the insoluble matter was filtered. The solvent was evaporated to dryness, and the obtained solid was washed twice with 20 ml of n-hexane. After drying, 4.6 g of POP(CH3)-Ir-CH3CO2 was obtained.

Example

[0039] The operation process of the hydroformylation reaction is as follows.

[0040] 81 mg of POP(CH3)-Ir-CH3CO2 of Example 5 and 12 ml of toluene were added into a 50 ml high-pressure reaction kettle. After performing hydrogen substitution three times, 3 bar of propylene, 8 bar of carbon monoxide, and 8 bar of hydrogen were introduced in this order, and the temperature was raised to 90 °C while stirring. At this temperature, the mixture was stirred for 8 hours to react, and the reaction solution was cooled to 0 °C. The pressure was slowly reduced, and the sample was taken... ​​Perform sampling and perform gas chromatographic analysis. Based on the results of gas chromatography, the turnover number of the catalyst TON is 78.8, and the selectivities of n-butylaldehyde and isobutylaldehyde are 99.8% (n-butylaldehyde / isobutylaldehyde = 29.1:1). It was possible to calculate 。 Comparative Example 1

[0041] Other operation steps are the same as those in Example 6. The difference is that the catalyst used is tris(2,4-di-tert-butylphenyl) phosphite-rhodium disclosed in CN111 -rhodium. The results are as shown below.

[0042] Table 3 Influence of differences in catalysts on the hydroformylation reaction TIFF0007705588000002.tif39141

[0043] As can be seen from the above table, in the process of the hydroformylation reaction using an iridium-based catalyst, when the temperature is 80 °C and the propylene gas pressure is 3 bar, the hydroformylation reaction is the best, and the present invention has obtained an n-butylaldehyde / isobutyl aldehyde ratio of up to 29.1:1. This demonstrates that the present invention has good reaction selectivity and reaction conversion rate even under low-temperature and low-pressure conditions. Furthermore, from the comparison with the rhodium catalyst of Comparative Example 1, it can also be seen that the new catalyst of the present invention not only reduces costs but also has superior catalytic activity compared to conventional catalysts. By performing a catalytic reaction with the new iridium-based catalyst employed in the present invention and exploring the reaction conditions, it has been realized to carry out the reaction under conditions of low energy consumption, and the reaction efficiency was also good.

[0044] Finally, the above-described embodiments are merely exemplary embodiments used for the purpose of explaining the principles of the present invention, and it should be understood that the present invention is not limited thereto. A person skilled in the art can make various modifications and improvements without departing from the principles and essence of the present invention, and those modifications and improvements are also considered to fall within the protection scope of the present invention.

Claims

【Claim 1】 A method for hydroformylating an olefin using an iridium-based catalyst, which comprises the following steps: Under the condition that an iridium-based catalyst is present, using an olefin, carbon monoxide, and hydrogen as raw materials to carry out a catalytic reaction; Before the reaction, dissolving the iridium-based catalyst in a solvent; The solvent is one of n-butyl aldehyde, isobutyl aldehyde, toluene or tetrahydro furan; The iridium-based catalyst has the following chemical structural formula: 【Chemical 1】 ; wherein Ph is a phenyl group, R is a methyl group or an ethyl group, and X is CH ３ CO ２ , NO ３ , BF ４ , PF ６ , SbF ６ is one or more of them, A method for preparing the iridium-based catalyst, comprising mixing and stirring 4,5-bis(diphenylphosphino)-9,9-dialkylxanthene, a solvent and an iridium compound, and further heating and stirring to obtain the iridium-based catalyst, wherein the time of the mixing and stirring is 2 h, in the heating and stirring, the temperature is raised to 50 °C and then stirred for 2 h, X in the iridium-based catalyst is CH ３ CO ２ 、NO ３ 、BF ４ 、PF ６ 、SbF ６ and is When, first, heating and stirring to obtain a substitution object, and then adding a compound containing an X group to the substitution object to carry out substitution; The partial pressure ratio of the olefin to the carbon monoxide is 5:1 to 1:5; The partial pressure ratio of the olefin to the hydrogen is 5:1 to 1:5; The mass of the iridium-based catalyst is 0.05 wt% to 1.0 wt% of the mass of the solvent, 、 provided that it excludes the case where the reaction temperature is 70-120 °C or the reaction pressure is 0.5-3. 0 MPa and the partial pressure of carbon monoxide is 1-10 bar in the presence of the iridium-based catalyst. A method for hydroformylating an olefin using an iridium-based catalyst, characterized by the above. 。

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