A method for preparing acetyl sucrose by using metal oxide cluster nanocatalyst

Abstract

This invention discloses a method for preparing styrax acetate using a metal-oxygen cluster nanocatalyst. The method involves first placing a metal-oxygen cluster nanocatalyst (with the molecular formula MaObX, where M can be any one of V, Cr, Nb, Mo, Ta, or W, a can be any integer between 1 and 20, b can be any integer between 6 and 70, and X can be any one of Mn, Fe, Co, Ni, Cu, or Zn) into a reactor. Then, α-phenylethanol and acetic acid are added to the reactor, and the reaction is carried out under specific temperature conditions. After separation and purification, styrax acetate is obtained. This method utilizes a metal-oxygen cluster nanocatalyst to catalyze the reaction of α-phenylethanol and acetic acid to prepare styrax acetate. This catalyst exhibits excellent catalytic activity and chemical stability, resulting in a high reaction yield. Even after multiple cycles, the catalytic efficiency does not decrease, saving production costs. Furthermore, the reaction does not generate additional waste acid or wastewater, making it environmentally friendly.

Description

Technical Field

[0001] This invention relates to the field of catalysis technology, specifically a method for preparing styrax acetate using a metal-oxygen cluster nanocatalyst. Background Technology

[0002] Straxyl acetate, chemically known as α-methylphenylmethyl acetate, is an important synthetic flavoring agent belonging to the carboxylic acid ester class. It is a transparent, colorless to pale yellow viscous liquid. It can be used to formulate various edible flavorings such as apple, pineapple, apricot, and peach, adding aroma to pastries, beverages, and other foods. It can also be used as a flavoring agent in daily chemical fragrances such as hyacinth, lilac, jasmine, lily of the valley, and magnolia, as well as specific fragrances like gardenia and tuberose. Furthermore, it is used as an additive in resins and inks.

[0003] Currently, traditional chemical synthesis processes typically involve preparing a haloethylbenzene intermediate by benzylic halogenation of ethylbenzene or by addition of styrene and halohydrogen, followed by reaction with sodium acetate. These processes suffer from problems such as high toxicity of raw materials, safety hazards during the reaction process, and significant pollution from post-processing. Therefore, there is an urgent need to develop new, green, and environmentally friendly synthesis methods.

[0004] Currently, the following are the publicly disclosed novel synthesis processes for styrax acetate both domestically and internationally: Patent CN102424650A uses styrene and acetic acid to prepare styrax acetate under the catalysis of rare earth halide salts, but the catalyst for this process is relatively expensive; Patent CN102079701A uses acetophenone hydrogenation to prepare α-phenylethanol, which is then reacted with acetic anhydride to prepare styrax acetate. This method produces acetic acid as a byproduct, making it neither economical nor environmentally friendly; Patent CN110090665A uses porous solid acid to catalyze the reaction of α-phenylethanol and acetic acid to prepare styrax acetate, but the reaction temperature is high and energy consumption is large.

[0005] Metal-oxygen cluster nanocatalysts are a newly emerging research hotspot in the field of catalysis. Metal-oxygen cluster nanocatalysts utilize metal-oxygen clusters (such as W6O) 19 Mo6O 24 The ligands coordinate with the central metal atom, effectively enhancing the chemical stability of the catalyst structure; different reactive sites can also be introduced by adjusting the composition and coordination mode of the metal-oxygen cluster.

[0006] This invention discloses a method for preparing styrax acetate using a metal-oxygen cluster nanocatalyst. The method involves first placing a metal-oxygen cluster nanocatalyst (with the molecular formula MaObX, where M can be any one of V, Cr, Nb, Mo, Ta, or W, a can be any integer between 1 and 20, b can be any integer between 6 and 70, and X can be any one of Mn, Fe, Co, Ni, Cu, or Zn) into a reactor. Then, α-phenylethanol and acetic acid are added to the reactor, and the reaction is carried out under specific temperature conditions. After separation and purification, styrax acetate is obtained. This method utilizes a metal-oxygen cluster nanocatalyst to catalyze the reaction of α-phenylethanol and acetic acid to prepare styrax acetate. This catalyst exhibits good catalytic activity and chemical stability, resulting in high reaction yield. Even after multiple cycles, the catalytic efficiency does not decrease, saving production costs. Furthermore, the reaction does not generate additional waste acid or wastewater, making it environmentally friendly. Summary of the Invention

[0007] To address the aforementioned shortcomings in existing technologies, this invention uses α-phenylethanol and acetic acid as raw materials and a metal-oxygen cluster nanocatalyst as the catalyst. Without the need for additional solvents, styrax ester of acetic acid is prepared under normal pressure using a magnetic stirrer. Compared to traditional methods, this method simplifies the process, improves product yield, is environmentally friendly, and most importantly, the catalyst is recyclable. Technical solution

[0008] A method for preparing styrax acetate using a metal-oxygen cluster nanocatalyst, characterized by the following specific steps: (1) Add α-phenylethanol and acetic acid to a reactor containing a catalyst, and stir the reaction at 80~120 °C for 1~6 h. After separation and purification, styrax acetic acid can be obtained. (2) Recover and reuse the catalyst used in step (1), and examine its catalytic activity. (3) Optimize the reaction conditions.

[0009] The general formula for the reaction of preparing styrax acetate by metal-oxygen cluster nanocatalysts involved in this invention is expressed as follows: Figure 1 .

[0010] Step 1) of this invention is characterized in that the catalyst has the molecular formula M. a O bX, where M can be any one of V, Cr, Nb, Mo, Ta, W, a can be any integer between 1 and 20, b can be any integer between 6 and 70, and X can be any one of Mn, Fe, Co, Ni, Cu, Zn. The amount of catalyst used is more suitable at 0.1 wt% to 5 wt%, with 1 wt% being optimal. The reaction temperature can be 80 to 120 ℃, with 110 ℃ being the best. The reaction time can be between 1 h and 6 h, with 3 h being optimal.

[0011] In step 2) of this invention, the catalyst is recycled. After the product is separated by distillation after the reaction, the metal oxygen cluster nanocatalyst in the system can be directly recovered and reused to catalyze the preparation of styrax acetate.

[0012] The optimal reaction conditions were obtained by screening factors such as catalyst type, catalyst dosage, temperature, and reaction time using the controlled variable method.

[0013] Compared with existing methods for preparing styrax acetate, this invention has the following advantages: low-cost catalyst raw materials, simple preparation process, high product yield, no waste, and environmental friendliness. The catalyst used is a novel type of catalyst—a metal-oxygen cluster nanocatalyst, with the metal being any one of the common V, Cr, Nb, Mo, Ta, W, Mn, Fe, Co, Ni, Cu, and Zn. The raw materials are inexpensive and readily available, and the catalyst can be recycled multiple times after simple treatment after the reaction, which is highly beneficial for industrial production. Therefore, this invention has potential application prospects. Attached Figure Description

[0014] Figure 1 This is the general reaction formula for the preparation of styrax acetic acid ester by metal-oxygen cluster nanocatalysts involved in this invention. Figure 2 It is a metal-oxygen cluster nanocatalyst (with V6O) 39 (Taking Cu as an example) Styrax acetate prepared by catalysis 1 HNMR image.

[0015] Figure 3 It is a metal-oxygen cluster nanocatalyst (with V6O) 39 (Taking Cu as an example) Styrax ester of acetate prepared by catalysis 1 CNMR image. Detailed Implementation

[0016] To provide a more detailed description of the present invention, several specific implementation examples are given below, but the present invention is not limited to these examples.

[0017] Example 1: 0.05 g of vanadium metal oxygen cluster nanocatalyst V5O with nickel atoms as the active center was added to a 30 mL clean reaction tube. 37 Ni, 10 mmol α-phenylethanol and 10 mmol acetic acid were reacted at 120 °C for 6 h. After the reaction, the esterification rate of the reaction substrate was found to be greater than 91% by GC-MS analysis. After separation and purification, the product was confirmed by NMR and mass spectrometry to be styrax acetic acid.

[0018] Example 2: 0.05 g of vanadium metal oxygen cluster nanocatalyst V6O with copper atoms as the active center was added to a 30 mL clean reaction tube. 39 Cu, 10 mmol α-phenylethanol and 10 mmol acetic acid were reacted at 120 °C for 6 h. After the reaction, the substrate was sampled and analyzed by GC-MS. The esterification rate of the substrate was greater than 95%. After separation and purification, the product was confirmed by NMR and mass spectrometry to be styrax acetic acid.

[0019] Example 3: 0.05 g of tungsten metal oxygen cluster nanocatalyst W with iron atoms as the active center was added to a 30 mL clean reaction tube. 12 O 40 Fe, 10 mmol α-phenylethanol and 10 mmol acetic acid were reacted at 120 °C for 6 h. After the reaction, the esterification rate of the reaction substrate was found to be greater than 90% by GC-MS analysis. After separation and purification, the product was confirmed by NMR and mass spectrometry to be styrax acetic acid ester.

[0020] Example 4: The reaction steps were the same as in Example 2, except that the catalyst dosage was 0.03 g. After the reaction, GC-MS analysis of the sample showed that the esterification rate of the substrate was greater than 94%. After separation and purification, NMR and mass spectrometry confirmed that the product was styrax acetate.

[0021] Example 5: The reaction steps were the same as in Example 2, except that the catalyst dosage was 0.01 g. After the reaction, GC-MS analysis of the sample showed that the esterification rate of the substrate was greater than 95%. After separation and purification, NMR and mass spectrometry confirmed that the product was styrax acetate.

[0022] Example 6: The reaction steps were the same as in Example 2, except that the catalyst dosage was 0.005 g. After the reaction, GC-MS analysis of the sample showed that the esterification rate of the substrate was greater than 88%. After separation and purification, NMR and mass spectrometry confirmed that the product was styrax acetate.

[0023] Example 7: The reaction procedure was the same as in Example 2, except that the catalyst dosage was 0.001 g. After the reaction, GC-MS analysis of the sample showed that the esterification rate of the substrate was greater than 83%. After separation and purification, NMR and mass spectrometry confirmed that the product was styrax acetate.

[0024] Example 8: 0.01 g of vanadium metal oxygen cluster nanocatalyst V6O with copper atoms as the active center was added to a 30 mL clean reaction tube. 39 Cu, 10 mmol α-phenylethanol and 10 mmol acetic acid were reacted at 110 °C for 6 h. After the reaction, the esterification rate of the reaction substrate was found to be greater than 97% by GC-MS analysis. After separation and purification, the product was confirmed by NMR and mass spectrometry to be styrax acetic acid.

[0025] Example 9: The reaction procedure was the same as in Example 8, except that the temperature was 100 °C. After the reaction, GC-MS analysis of the sample showed that the esterification rate of the substrate was greater than 93%. After separation and purification, NMR and mass spectrometry confirmed that the product was styrax acetate.

[0026] Example 10: The reaction procedure was the same as in Example 8, except that the temperature was 90 °C. After the reaction, GC-MS analysis of the sample showed that the esterification rate of the substrate was greater than 55%. After separation and purification, NMR and mass spectrometry confirmed that the product was styrax acetate.

[0027] Example 11: The reaction procedure was the same as in Example 8, except that the temperature was 80 °C. After the reaction, GC-MS analysis of the sample showed that the esterification rate of the substrate was greater than 80%. After separation and purification, NMR and mass spectrometry confirmed that the product was styrax acetate.

[0028] Example 12: The reaction procedure was the same as in Example 8, except that the reaction time was 3 hours. After the reaction, GC-MS analysis of the sample showed that the esterification rate of the substrate was greater than 97%. After separation and purification, NMR and mass spectrometry confirmed that the product was styrax acetate.

[0029] Example 13: The reaction procedure was the same as in Example 8, except that the reaction time was 1 h. After the reaction, GC-MS analysis of the sample showed that the esterification rate of the substrate was greater than 82%. After separation and purification, NMR and mass spectrometry confirmed that the product was styrax acetate.

[0030] Example 14: The reaction procedure was the same as in Example 8, except that the catalyst was being used for the first time after being recovered. After the reaction, GC-MS analysis of the sample showed that the esterification rate of the substrate was greater than 95%. After separation and purification, NMR and mass spectrometry confirmed that the product was styrax acetate.

[0031] The main reaction conditions and results in the examples are shown in the table below: Example Catalyst types Catalyst dosage (wt%) Temperature (°C) Reaction time (h) Yield (%) 1 V5O 37 Ni]] 5 120 6 91 2 V6O 39 Cu]] 5 120 6 95 3 [CATALOGUE] W 12 O 40 Fe]]> 5 120 6 90 4 <![CDATA[V6O 39 With]]> 3 120 6 94 5 <![CDATA[V6O 39 With]]> 1 120 6 95 6 <![CDATA[V6O 39 With]]> 0.5 120 6 88 7 <![CDATA[V6O 39 With]]> 0.1 120 6 83 8 <![CDATA[V6O 39 With]]> 1 110 6 97 9 <![CDATA[V6O 39 With]]> 1 100 6 93 10 <![CDATA[V6O 39 With]]> 1 90 6 85 11 <![CDATA[V6O 39 With]]> 1 80 6 80 12 <![CDATA[V6O 39 With]]> 1 110 3 97 13 <![CDATA[V6O 39 With]]> 1 110 1 82 14 <![CDATA[V6O 39 Cu (recycling) 1 110 3 95 .

[0032] All the above-described primary embodiments do not specify other forms of implementing this new product and / or method. Those skilled in the art will utilize this important information to modify the above descriptions to achieve similar implementations. However, all modifications or alterations based on this invention are subject to the rights reserved by this invention.

[0033] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for preparing styrax acetate using a metal-oxygen cluster nanocatalyst, characterized in that, The specific steps are as follows: (1) Add the metal oxide cluster nanocatalyst to a clean reaction vessel, then add the raw materials α-phenylethanol and acetic acid, and react fully under magnetic stirring at 80~120 °C for about 1~6 h. After the reaction, styrax acetic acid can be obtained by separation and purification. (2) The catalytic activity of the metal oxide cluster nanocatalyst used in step (1) is investigated after recycling and reuse. (3) Optimize the reaction conditions.

2. The preparation method according to claim 1, characterized in that: In step 1), the metal-oxygen cluster nanocatalyst has the molecular formula M. a O b X, where M can be any one of V, Cr, Nb, Mo, Ta, W, a can be any integer between 1 and 20, b can be any integer between 6 and 70, and X can be any one of Mn, Fe, Co, Ni, Cu, Zn.

3. The preparation method according to claim 1, characterized in that: In step 1), no reaction solvent is required, the reaction temperature is 80℃~120℃, and the reaction time is 1 h~6 h.

4. The preparation method according to claim 1, characterized in that, In step 2), the catalyst is recycled. After the product is separated by distillation after the reaction, the metal oxygen cluster nanocatalyst in the system can be directly recovered and reused to catalyze the preparation of styrax acetate.

5. The preparation method according to claim 1, characterized in that, In step 3), the controlled variable method is used to screen factors such as the type of catalyst, the amount of catalyst, the temperature, and the reaction time to obtain the optimal reaction conditions.

6. The preparation method according to claim 1, wherein the catalyst is characterized in that the catalyst molecular formula can be represented as M a O b X, where M can be any one of V, Cr, Nb, Mo, Ta, W, a can be any integer between 1 and 20, b can be any integer between 6 and 70, X can be any one of Mn, Fe, Co, Ni, Cu, Zn, and the amount of catalyst used is 0.1 wt% to 5 wt%.

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