Metal nanoclusters, their preparation methods and applications, and methods for coupling terminal olefins with benzyl alcohols.

Abstract

This invention relates to a metal nanocluster, its preparation method and application, and a method for coupling terminal olefins with benzyl alcohols. The metal nanocluster contains a Group VIII metal element, and the diameter of the metal nanocluster is 0.1-10 nm. The metal nanoclusters of this invention have a relatively large size, which enables them to be effectively used for catalyzing the reaction of olefins with benzyl alcohols.

Description

Technical Field

[0001] This invention relates to a metal nanocluster, its preparation method and application, and a method for coupling terminal olefins with benzyl alcohol compounds. Background Technology

[0002] The main methods for synthesizing metal nanoclusters include reduction growth, seed growth, alloying, and ligand exchange. Reduction growth focuses on reduction, specifically the process of reducing a high-valence metal with a reducing agent. The rate of reduction and the strength of the reducing agent are crucial to the success of the reaction. Although many nanocluster structures have been obtained, most are still relatively small. Larger nanoclusters offer vital opportunities for exploration and understanding for materials chemists. Currently, an important task is to increase the size of these clusters.

[0003] α-Aryl-2-methylbutenols are important intermediates in organic synthesis, commonly used in the synthesis of pharmaceutical intermediates, pesticide intermediates, and fragrances. However, conventional synthesis requires halogenated olefins or involves multiple transformations of the olefin before reacting it with other substrates to obtain the target product, resulting in long routes and numerous steps. Direct synthesis methods require special synthetic steps for catalysts or ligands, making them unsuitable for large-scale applications. Summary of the Invention

[0004] The purpose of this invention is to overcome the problem of poor catalytic performance of existing metal nanoclusters, which prevents them from being used for efficient reactions of olefins and benzyl alcohols. This invention provides a metal nanocluster, its preparation method, its application, and a method for coupling terminal olefins with benzyl alcohols. This metal nanocluster exhibits excellent catalytic performance, significantly improving the efficiency of coupling terminal olefins with benzyl alcohols.

[0005] To achieve the above objectives, the first aspect of the present invention provides a metal nanocluster, wherein the metal in the metal nanocluster comprises a group VIII metal element, and the diameter of the metal nanocluster is 0.1-10 nm.

[0006] A second aspect of the present invention provides a method for preparing metal nanoclusters, the method comprising: dissolving a Group VIII metal compound in a solvent under an inert gas atmosphere, slowly adding arylboronic acid, and dynamically contacting and reducing the compound.

[0007] A third aspect of the present invention provides a metal nanocluster prepared by the preparation method described in the present invention.

[0008] The fourth aspect of this invention provides the application of the metal nanoclusters described in the first aspect and the third aspect of this invention in the catalytic coupling reaction of olefins and benzyl alcohols.

[0009] The fifth aspect of the present invention provides a method for coupling terminal olefins with benzyl alcohols, the method comprising: contacting and reacting terminal olefins and benzyl alcohols in the presence of a catalyst and a sulfonic acid, wherein the catalyst comprises the metal nanoclusters described in one aspect of the present invention and the metal nanoclusters described in three aspects of the present invention.

[0010] Through the above technical solution, the present invention has the following beneficial effects:

[0011] The metal nanoclusters of this invention are relatively large in size, which makes them well-suited for catalyzing the reaction of olefins with benzyl alcohols.

[0012] The metal nanoclusters of this invention do not require complex catalyst synthesis steps; they only require the pre-reduction of group VIII metal salts with a reducing agent. Furthermore, the addition of sulfonic acid during use can effectively catalyze the reaction of terminal olefins and benzyl alcohols. In other words, the metal nanoclusters of this application are simple to prepare, have a short synthesis route, and are highly atom-economical. Attached Figure Description

[0013] Figure 1 This is a TEM image of a metal nanocluster prepared according to a preferred embodiment of the present invention. Detailed Implementation

[0014] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0015] This invention provides a metal nanocluster, wherein the metal in the metal nanocluster comprises a Group VIII metal element, and the diameter of the metal nanocluster is 0.1-10 nm.

[0016] The metal nanoclusters of the present invention have the aforementioned characteristics. The metal nanoclusters of the present invention have a large size and can be well used to catalyze the reaction of olefins and benzyl alcohols, with high catalytic efficiency.

[0017] According to a preferred embodiment of the present invention, the diameter of the metal nanoclusters is 0.5-3 nm. By adopting the aforementioned preferred embodiment, the efficiency of the coupling reaction between olefins and benzyl alcohols catalyzed by metal nanoclusters can be further improved.

[0018] Any Group VIII metal element can be used in this invention. According to a preferred embodiment of the invention, the Group VIII metal element is selected from at least one of Ru, Ir, Co, and Rh, preferably Ru. By adopting the aforementioned preferred embodiment, the efficiency of metal nanoclusters in catalyzing the coupling reaction of olefins and benzyl alcohols can be further improved.

[0019] This invention provides a method for preparing metal nanoclusters, the method comprising: dissolving a Group VIII metal compound in a solvent under an inert gas atmosphere, slowly adding arylboronic acid, and dynamically contacting and reducing the compound.

[0020] The method of this invention for preparing metal nanoclusters does not require complex catalyst synthesis steps. It only requires the pre-reduction of group VIII metal salts with a reducing agent. Furthermore, the addition of sulfonic acid during use can effectively catalyze the reaction of terminal olefins and benzyl alcohols. In other words, the metal nanoclusters prepared in this application are simple to prepare, have a short synthetic route, and are highly atom-economical.

[0021] According to a preferred embodiment of the present invention, the inert gas is selected from at least one of nitrogen, helium, and argon.

[0022] According to a preferred embodiment of the present invention, the Group VIII metal compound is selected from compounds of at least one metal selected from Ru, Ir, Co, and Rh. The compound may be, for example, a halide salt, acetate, acetylacetone complex, or phosphorus complex corresponding to each element.

[0023] According to a preferred embodiment of the present invention, the Group VIII metal compound is a compound of Ru metal, specifically such as RuI3, RuCl3, RuBr3, Ru(OAc)3, Ru(acac)3, and RuCl2Ph3.

[0024] In this invention, the range of arylboronic acids that can be selected is relatively wide as long as the objective of this invention can be achieved. According to a preferred embodiment of this invention, the arylboronic acid is selected from at least one of phenylboronic acid, 3-acyl-4-methylphenylboronic acid, 3-fluorophenylboronic acid, and 2,4-difluorophenylboronic acid, preferably phenylboronic acid. By adopting the aforementioned preferred embodiment, the size of the metal nanoclusters can be improved, thereby increasing the efficiency of the metal nanoclusters in catalyzing the coupling reaction of olefins and benzyl alcohols.

[0025] In this invention, the type of solvent is not particularly required. According to a preferred embodiment of this invention, the solvent is selected from at least one of tetrahydrofuran, 2-methyltetrahydrofuran, 3-methyltetrahydrofuran, 2,5-dimethoxytetrahydrofuran, 2,2-dimethyltetrahydrofuran, toluene, p-xylene, o-xylene, m-xylene, dichloromethane, chloroform, diethyl ether, and acetonitrile.

[0026] In this invention, as long as the purpose of this invention can be achieved, there are no special requirements on the mass ratio of the solvent, the group VIII metal compound and the arylboronic acid. According to a preferred embodiment of this invention, the mass ratio of the solvent, the group VIII metal compound and the arylboronic acid is 80-300:0.1-10:1, preferably 100-200:0.5-5:1.

[0027] In this invention, the conditions for contact reduction can be selected from a wide range, and the dynamic contact method can be, for example, stirring.

[0028] According to a preferred embodiment of the present invention, the conditions for contact reduction include a temperature of 5-60°C, preferably 20-35°C.

[0029] According to a preferred embodiment of the present invention, the contact reduction conditions include a time of 0.1-5 hours, preferably 0.5-1 hours.

[0030] This invention provides a metal nanocluster prepared by the method described herein. This metal nanocluster has a relatively large size and can be effectively used to catalyze the reaction of olefins with benzyl alcohols, exhibiting high catalytic efficiency.

[0031] This invention provides an application of the metal nanoclusters described herein in the catalytic coupling reaction of olefins and benzyl alcohols.

[0032] Applying the metal nanoclusters of the present invention to the catalytic coupling reaction of terminal olefins and benzyl alcohols has the effect of high catalytic efficiency.

[0033] This invention provides a method for coupling terminal olefins with benzyl alcohols, the method comprising: contacting and reacting terminal olefins and benzyl alcohols in the presence of a catalyst and sulfonic acid, wherein the catalyst comprises the metal nanoclusters described in this invention.

[0034] The method of this invention for coupling terminal olefins with benzyl alcohols has the advantage of high catalytic efficiency.

[0035] In this invention, the range of sulfonic acids is relatively wide. According to a preferred embodiment of the invention, the sulfonic acid is selected from at least one of benzenesulfonic acid, p-toluenesulfonic acid, p-trifluoromethylbenzenesulfonic acid, and 2,4,6-trimethylbenzenesulfonic acid. By adopting the aforementioned preferred embodiment, the catalytic efficiency of terminal olefins and benzyl alcohols can be further improved.

[0036] In this invention, the type of terminal olefin is not particularly important as long as the objective of the invention can be achieved. According to a preferred embodiment of the invention, the terminal olefin is a conjugated terminal olefin. For example, it can be butadiene.

[0037] According to a preferred embodiment of the present invention, the benzyl alcohol compound has a structure as shown in formula (1).

[0038]

[0039] In formula (1), R is selected from at least one of hydrogen, halogen, C1-C10 alkanes, C2-C10 alkenes, halogenated C1-C10 alkanes, C1-C10 alkoxy groups, and C6-C9 aromatic hydrocarbons. Specifically, benzyl alcohol compounds may be, for example, benzyl alcohol, 4-methylbenzyl alcohol, 2-methylbenzyl alcohol, or 4-vinylbenzyl alcohol. By employing the aforementioned preferred embodiment, the catalytic efficiency of terminal olefins and benzyl alcohol compounds can be further improved.

[0040] In this invention, the range of selectable contact reaction conditions is relatively wide.

[0041] According to a preferred embodiment of the present invention, the conditions for the contact reaction include a temperature of 30-150°C, preferably 60-120°C.

[0042] According to a preferred embodiment of the present invention, the conditions for the contact reaction include a time of 0.01-48 h, preferably 10-25 h.

[0043] According to a preferred embodiment of the present invention, the conditions for the contact reaction include: the mass ratio of catalyst, sulfonic acid, terminal olefin and benzyl alcohol compound is 1:1-15:100-800:40-300, preferably 1:2-10:130-450:40-200.

[0044] The present invention will be described in detail below through examples. In the following examples, the product yield parameters were determined by liquid chromatography (or by using appropriate equipment); the catalyst structural characteristics and the size of the metal nanoparticles were tested using a G2F30 transmission electron microscope (TEM) from FEI Corporation, USA. All raw materials were commercially available.

[0045] Yield = (moles of product / moles of starting material benzyl alcohol) × 100%

[0046] Example 1

[0047] In an autoclave, 99.2 mg of RuI3, 15 g of tetrahydrofuran, and 61 mg of phenylboronic acid were added. After purging with nitrogen, the mixture was stirred at room temperature for 20 minutes. Samples were taken and analyzed using a FEI G2F30 transmission electron microscope (TEM) from the USA. Figure 1The figure shows that the diameter of the metal nanoclusters is 0.5-3 nm. Then, 158 mg of benzyl sulfonic acid, 3.1 g of benzyl alcohol, and 10 g of cooled butadiene were added, and the reaction was carried out at 85 °C for 20 hours. After natural cooling, the gas was carefully released in a fume hood, and the residue was analyzed by liquid chromatography to obtain the target product. The results showed that the yield of α-phenyl-2-methylbutenol could reach 90%.

[0048] Example 2

[0049] In an autoclave, 63.5 mg of CoAc2, 15 g of 2-methyltetrahydrofuran, and 65 mg of phenylboronic acid were added. After purging with nitrogen, the mixture was stirred at room temperature for 20 minutes. Samples were taken and analyzed using a FEI G2F30 transmission electron microscope (TEM) to obtain TEM images. Figure 1 Similarly, the figure shows that the diameter of the metal nanoclusters is 0.5-3 nm. Then, 162 mg of p-toluenesulfonic acid, 3.2 g of 4-methylbenzyl alcohol, and 10 g of cooled butadiene were added, and the reaction was carried out at 85 °C for 20 hours. After natural cooling, the gas was carefully released in a fume hood, and the residue was analyzed by liquid chromatography to obtain the target product. The results showed that the yield of α-(4-methylphenyl)-2-methylbutenol reached 87%.

[0050] Example 3

[0051] In a 100g autoclave, 100.8mg of Ir(acac)3, 15g of toluene, and 67mg of phenylboronic acid were added. After purging with nitrogen, the mixture was stirred at room temperature for 20 minutes. Samples were taken and analyzed using a FEI G2F30 transmission electron microscope (TEM) to obtain TEM images. Figure 1 Similarly, the figure shows that the diameter of the metal nanoclusters is 0.5-3 nm. Then, 185 mg of 2,4,6-trimethylbenzenesulfonic acid, 3.2 g of 2-methylbenzyl alcohol, and 10 g of cooled butadiene were added, and the reaction was carried out at 85 °C for 20 hours. After natural cooling, the gas was carefully released in a fume hood, and the residue was analyzed by liquid chromatography to obtain the target product. The results showed that the yield of α-(2-methylphenyl)-2-methylbutenol reached 88%.

[0052] Example 4

[0053] Same as Example 1, except that butadiene was replaced with 1-butene. Results showed that the yield of α-phenyl-2-methylbutanol reached 79%.

[0054] Example 5

[0055] Same as Example 1, except that phenylboronic acid was replaced with 3-fluorophenylboronic acid, and the samples were tested using a G2F30 transmission electron microscope (TEM) from FEI Corporation, USA, to obtain TEM images. Figure 1Similarly, the figures show that the diameters of the metal nanoclusters range from 0.1 to 10 nm. The results indicate that the yield of α-phenyl-2-methylbutenol can reach 80%.

[0056] Comparative Example 1

[0057] In a 100g autoclave, 99.2mg of RuI3 and 15g of tetrahydrofuran were added. After purging with nitrogen, the mixture was stirred at room temperature for 20 minutes. Then, 158mg of benzylsulfonic acid, 3.1g of benzyl alcohol, and 10g of cooled butadiene were added, and the reaction was carried out at 85℃ for 20 hours. After natural cooling, the gas was carefully released in a fume hood, and the residue was analyzed by liquid chromatography to obtain the target product. The results showed that the yield of α-aryl-2-methylbutenol was 8%.

[0058] Comparative Example 2

[0059] In a 100g autoclave, 99.2mg of RuI3 and 15g of tetrahydrofuran were added. After purging with nitrogen, 1MPa of H2 was introduced, and the mixture was stirred at room temperature for 20 minutes. Then, 158mg of benzyl sulfonic acid, 3.1g of benzyl alcohol, and 10g of cooled butadiene were added, and the reaction was carried out at 85℃ for 20 hours. After natural cooling, the gas was carefully released in a fume hood, and the residue was analyzed by liquid chromatography to obtain the target product. The results showed that the yield of α-phenyl-2-methylbutenol reached 6%.

[0060] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. The application of a metal nanocluster in the catalytic coupling reaction of terminal olefins and benzyl alcohols in the presence of sulfonic acid, characterized in that, The metal in the metal nanoclusters contains Group VIII metal elements, and the diameter of the metal nanoclusters is 0.1-10 nm; The group VIII metallic element is selected from at least one of Ru, Ir, Co, and Rh; The method for preparing the metal nanoclusters includes: dissolving a Group VIII metal compound in a solvent under an inert gas atmosphere, slowly adding arylboronic acid, and dynamically reducing the mixture through contact.

2. The application according to claim 1, wherein, The diameter of the metal nanoclusters is 0.5-3 nm.

3. The application according to claim 1, wherein, The group VIII metal element is Ru.

4. The application according to claim 1, wherein, The Group VIII metal compound is selected from compounds of at least one metal chosen from Ru, Ir, Co, and Rh; and / or The arylboronic acid is selected from at least one of phenylboronic acid, 3-acyl-4-methylphenylboronic acid, 3-fluorophenylboronic acid, and 2,4-difluorophenylboronic acid; and / or The solvent is selected from at least one of tetrahydrofuran, 2-methyltetrahydrofuran, 3-methyltetrahydrofuran, 2,5-dimethoxytetrahydrofuran, 2,2-dimethyltetrahydrofuran, toluene, p-xylene, o-xylene, m-xylene, dichloromethane, chloroform, diethyl ether, and acetonitrile.

5. The application according to claim 4, wherein, The Group VIII metal compound is a compound of Rh metal; and / or The arylboronic acid is phenylboronic acid.

6. The application according to claim 1, wherein, The mass ratio of the solvent, the Group VIII metal compound, and the arylboronic acid is 80-300:0.1-10:1; and / or The conditions for contact reduction include: The temperature is 5-60℃; and / or The time is 0.1-5 hours.

7. The application according to claim 6, wherein, The mass ratio of the solvent, the group VIII metal compound, and the arylboronic acid is 100-200:0.5-5:1; and / or The conditions for contact reduction include: The temperature is 20-35℃; and / or The time is 0.5-1 hour.

8. A method for coupling terminal olefins with benzyl alcohols, characterized in that, The method includes: reacting terminal olefins and benzyl alcohols in the presence of a catalyst and sulfonic acid, wherein, The catalyst is a metal nanocluster, wherein the metal in the metal nanocluster contains a group VIII metal element, and the diameter of the metal nanocluster is 0.1-10 nm. The group VIII metallic element is selected from at least one of Ru, Ir, Co, and Rh; The method for preparing the metal nanoclusters includes: dissolving a Group VIII metal compound in a solvent under an inert gas atmosphere, slowly adding arylboronic acid, and dynamically reducing the mixture in contact. The sulfonic acid is selected from at least one of benzenesulfonic acid, p-toluenesulfonic acid, p-trifluoromethylbenzenesulfonic acid, and 2,4,6-trimethylbenzenesulfonic acid; The terminal olefin is a conjugated terminal olefin; The benzyl alcohol compounds have the structure shown in formula (1). ； In formula (1), R is selected from at least one of hydrogen, halogen, C1-C10 alkanes, C2-C10 alkenes, halogenated C1-C10 alkanes, C1-C10 alkoxy groups, and C6-C9 aromatic hydrocarbons.

9. The method according to claim 8, wherein, The conditions for the contact reaction include: Temperatures range from 30 to 150°C; and / or The time is 0.01-48h; and / or The mass ratio of catalyst, sulfonic acid, terminal olefin and benzyl alcohol is 1:1-15:100-800:40-300.

10. The method according to claim 9, wherein, The conditions for the contact reaction include: Temperature is 60-120℃; and / or The time is 10-25 hours; and / or The mass ratio of catalyst, sulfonic acid, terminal olefin and benzyl alcohol is 1:2-10:130-450:40-200.

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