A 2,2-dialkoxymethyl-5-alkoxymethylfuran and its preparation method
By employing a two-step reaction with a NiZrPOx/SiO2 catalyst and an acidic catalyst, the problem of low yield of 2,2-dialkoxymethyl-5-alkoxymethylfuran was solved, achieving efficient preparation of high-energy-density alkoxyfuran compounds and providing a foundation for the research of bio-based fuels and additives.
Patent Information
- Application Number
- CN202410130844.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-30
- Publication Date
- 2026-01-30
- Estimated Expiration
- 2044-01-30
AI Technical Summary
In the existing technology, the preparation method of 2,2-dialkoxymethyl-5-alkoxymethylfuran has low yield and cannot meet the standard index. In addition, its selectivity and yield are both low, making it difficult to achieve efficient preparation.
2,2-Dialkoxymethyl-5-alkoxymethylfuran was prepared by reacting the biomass platform compound 5-hydroxymethylfurfural with a NiZrPOx/SiO2 catalyst and an acidic catalyst in an alcohol solvent, followed by a two-step process of pH adjustment and vacuum distillation.
The efficient preparation of 2,2-dialkoxymethyl-5-alkoxymethylfuran has been achieved, filling a gap in preparation methods and providing a research basis for high-energy-density bio-based fuels or additives.
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Figure CN118026972B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of catalysis and energy chemical technology, specifically relating to a 2,2-dialkoxymethyl-5-alkoxymethylfuran and its preparation method. Background Technology
[0002] Biomass platform compounds, with their green and renewable characteristics, as well as their wide availability and rich functional structures, are considered to have enormous potential value in the fields of fine chemical preparation and energy chemical engineering. Among them, 5-hydroxymethylfurfural can undergo etherification, transfer hydrogenation, and acetalization reactions with alcohols through different catalytic sites to prepare valuable alkoxyfuran-based bio-based fuels or additives, including alkoxyfurfural and diekoxyfurans. Generally, catalytic conversion of furfural compounds to alkoxyfurans increases their molecular weight, thereby improving their calorific value and energy density as petroleum products. Currently, most reports on the preparation of alkoxyfurans from 5-hydroxymethylfurfural focus on 5-alkoxyfurfural and 2,5-diekoxymethylfuran products. 2,2-diekoxymethyl-5-alkoxymethylfuran, as a superior ether product with a larger molecular weight, has only been reported as a byproduct in some related studies, with low selectivity and yield, and is prone to further conversion at unfavorable sites in the system. Therefore, it is of great significance to develop an efficient method and conversion pathway for the preparation of 2,2-dialkoxymethyl-5-alkoxymethylfuran.
[0003] As is well known, 5-hydroxymethylfurfural can pass through Acidic sites can undergo etherification and ring-opening reactions. Lewis acids can catalyze the transfer hydrogenation of their aldehyde groups, and can also undergo acetalization and polymerization reactions in the presence of basic sites. Furthermore, when the catalyst contains both acidic and basic sites, some reactions can proceed in reverse. The preparation of 2,2-dialkoxymethyl-5-alkoxymethylfuran requires suitable... The involvement of acidic and basic sites, but Acid sites severely interfere with acetalization reactions catalyzed by basic sites. Furthermore, the suitable basic site for acetal reactions—the Lewis base—usually coexists with a Lewis acid in an acid-base pair, causing the substrate to proceed via transfer hydrogenation, thus preventing the yield of the 2,2-dialkoxymethyl-5-alkoxymethylfuran product. Additionally, there are currently no commercially available products (or standards) of 2,2-dialkoxymethyl-5-alkoxymethylfuran, although it is frequently reported in some studies with low yields. Therefore, developing a method for its preparation would facilitate qualitative and quantitative analysis and hold promise for the development and utilization of its downstream products. Summary of the Invention
[0004] In order to overcome the shortcomings of the prior art, the present invention aims to provide a 2,2-dialkoxymethyl-5-alkoxymethylfuran and its preparation method, so as to solve the technical problems of low yield and inability to meet the standard indicators in the existing preparation methods of 2,2-dialkoxymethyl-5-alkoxymethylfuran.
[0005] To achieve the above objectives, the present invention employs the following technical solution:
[0006] This invention discloses a method for preparing 2,2-dialkoxymethyl-5-alkoxymethylfuran, comprising the following steps:
[0007] S1: Biomass platform compounds, An acidic catalyst and an alcohol solvent are mixed and stirred to produce a reaction solution A.
[0008] S2: NiZrPOx / SiO2 catalyst is added to the reaction solution and reacted under heating reflux and dehydration conditions to obtain reaction solution B; then the pH value of reaction solution B is adjusted, and the solvent is removed by vacuum distillation to obtain 2,2-dialkoxymethyl-5-alkoxymethylfuran.
[0009] Further, in S1, the biomass platform compound is 5-hydroxymethylfurfural; Acidic catalysts include 5-sulfosalicylic acid, p-toluenesulfonic acid, and carbon-based solid acid catalysts.
[0010] Furthermore, in S1, the alcohol solvent is methanol or isopropanol.
[0011] Furthermore, in S1, the biomass platform compound, The ratio of acidic catalyst to alcohol solvent is 1g:(0.033~2)g:(12~60)mL.
[0012] Furthermore, in S1, the reaction time is 30 min to 6 h, and the reaction temperature is 70 °C to 130 °C.
[0013] Furthermore, in S2, the preparation method of the NiZrPOx / SiO2 catalyst is as follows:
[0014] Tetraethyl silicate, nickel acetate, zirconium oxychloride, diammonium hydrogen phosphate, tetrapropylammonium hydroxide, and acetylacetone were mixed in an alcohol-water mixed solvent at a mass ratio of 1:0.206:0.053:0.16:1:0.33, then hydrothermally heated at 180°C for 24 h, and calcined at 600°C for 3 h to obtain the final product.
[0015] Furthermore, in S2, the mass ratio of the NiZrPOx / SiO2 catalyst to the biomass platform compound is 0.167–2.33.
[0016] Furthermore, in S2, the pH value of the reaction solution B is adjusted within the range of 7.5 to 8.5.
[0017] Furthermore, in S2, the reaction time is 3h to 8h, and the reaction temperature is 80℃ to 140℃.
[0018] The present invention also discloses 2,2-dialkoxymethyl-5-alkoxymethylfuran prepared by the above preparation method.
[0019] Compared with the prior art, the present invention has the following beneficial effects:
[0020] This invention discloses a method for preparing 2,2-dialkoxymethyl-5-alkoxymethylfuran. Through a suitable and specific catalytic site, a two-step method efficiently and selectively converts biomass platform compound molecules into high-energy-density alkoxyfuran compounds. This method fills the gap in the preparation methods and production processes of 2,2-dialkoxymethyl-5-alkoxymethylfuran compounds. This method holds promise for the mass production of 2,2-dialkoxymethyl-5-alkoxymethylfuran products and their application in research on bio-based fuels or additives (including necessary pathway derivation, standard synthesis, and the development and utilization of downstream products). Attached Figure Description
[0021] Figure 1 This describes the catalytic conversion reaction pathway of 5-hydroxymethylfurfural in alcohol solvents.
[0022] Figure 2 Mass spectrometry identification results of 2,2-dialkoxymethyl-5-alkoxymethylfuran products;
[0023] Wherein: a-2,2-bismethoxymethyl-5-methoxymethylfuran; b-2,2-bisisopropoxymethyl-5-isopropoxymethylfuran. Detailed Implementation
[0024] To enable those skilled in the art to understand the features and effects of the present invention, the terms and expressions used in the specification and claims are explained and defined in general below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding the present invention, and in case of conflict, the definitions in this specification shall prevail.
[0025] The theories or mechanisms described and disclosed herein, whether right or wrong, should not in any way limit the scope of the invention, that is, the contents of the invention can be implemented without being limited by any particular theory or mechanism.
[0026] In this document, all features defined by numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible sub-ranges and individual numerical values (including integers and fractions) within those ranges.
[0027] In this article, unless otherwise specified, “contains,” “includes,” “containing,” “has,” or similar terms cover the meanings of “composed of” and “mainly composed of,” for example, “A contains a” covers the meanings of “A contains a and others” and “A contains only a.”
[0028] For the sake of brevity, not all possible combinations of the technical features in each implementation scheme or embodiment are described herein. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each implementation scheme or embodiment can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification.
[0029] This invention provides a method for preparing 2,2-dialkoxymethyl-5-alkoxymethylfuran, comprising the following steps:
[0030] Step 1: Combine the biomass platform compound 5-hydroxymethylfurfural with... An acidic catalyst is added to 12-60 mL of an alcohol solvent at a mass ratio of 1:0.033 to 1:2, and stirred at the reaction temperature until the reaction time is reached to obtain reaction solution A.
[0031] Step 2: Separate the catalyst from reaction solution A obtained in Step 1, and then continue to add a certain amount of NiZrPOx / SiO2 catalyst to reaction solution A. React under the conditions of heating and reflux and dehydration until the required time is reached. After filtering out the catalyst, reaction solution B is obtained. Adjust the pH of reaction solution B to slightly alkaline, and remove the solvent by vacuum distillation to obtain the corresponding 2,2-dialkoxymethyl-5-alkoxymethylfuran.
[0032] Among them, the steps described in step one The acidic catalyst includes 5-sulfosalicylic acid, p-toluenesulfonic acid, and a carbon-based solid acid catalyst (wherein the carbon-based solid acid catalyst is the catalyst described in the applicant's authorized patent CN114768828B); the corresponding alcohol solvent in step one is methanol or isopropanol; the NiZrPOx / SiO2 catalyst in step two is tetraethyl silicate, nickel acetate, zirconium oxychloride, diammonium hydrogen phosphate, tetrapropylammonium hydroxide, and acetylacetone in a mass ratio of 1:0.206:0.053:0.16:1:0.33. The reaction mixture was prepared by hydrothermal treatment at 180°C for 24 hours in an alcohol-water mixed solvent, followed by calcination at 600°C for 3 hours. In step two, the mass ratio of the NiZrPOx / SiO2 catalyst to the starting substrate 5-hydroxymethylfurfural was 0.167–2.33. In step two, the pH of the reaction solution was adjusted to a range of 7.5–8.5. In step one, the reaction time was 30 min–6 h and the reaction temperature was 70°C–130°C. In step two, the reaction time was 3 h–8 h and the reaction temperature was 80°C–140°C.
[0033] Preferably, in step one: the biomass platform compound 5-hydroxymethylfurfural and 5-sulfosalicylic acid are added to isopropanol at a mass ratio of 1:0.133, and stirred at 80°C for 5 hours;
[0034] Step 2: Separate the catalyst from reaction solution A obtained in Step 1, and then continue to add NiZrPOx / SiO2 catalyst with a mass ratio of 1:0.33 to 5-hydroxymethylfurfural to reaction solution A. Reflux and remove water at 110℃ for 5 h. After filtering out the catalyst, reaction solution B is obtained. Adjust the pH of reaction solution B to 8.0, and remove the solvent by vacuum distillation to obtain 2,2-bisisopropoxymethyl-5-isopropoxymethylfuran with a yield of 96.7%.
[0035] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.
[0036] The following examples use instruments and equipment conventional in the art. Experimental methods in the following examples, unless otherwise specified, are generally performed under conventional conditions or as recommended by the manufacturer. All raw materials used in the following examples are conventional commercially available products with specifications conventional in the art. In this specification and the following examples, unless otherwise specified, "%" refers to weight percentage, "parts" refers to parts by weight, and "ratio" refers to weight proportion.
[0037] Example 1
[0038] A method for preparing 2,2-dialkoxymethyl-5-alkoxymethylfuran includes the following steps:
[0039] Step 1: Add 0.5g of the biomass platform compound 5-hydroxymethylfurfural and 5-sulfosalicylic acid to 6mL of isopropanol at a mass ratio of 1:0.133, and stir at 80℃ for 5h to obtain reaction solution A;
[0040] Step 2: Separate the catalyst from the reaction solution obtained in Step 1, and then continue to add NiZrPOx / SiO2 catalyst with a mass ratio of 1:0.33 to 5-hydroxymethylfurfural to reaction solution A. Reflux and remove water at 110℃ for 5 h. After filtering out the catalyst, reaction solution B is obtained. Adjust the pH of reaction solution B to 8.0, and remove the solvent by vacuum distillation to obtain 2,2-bisisopropoxymethyl-5-isopropoxymethylfuran with a yield of 96.7%.
[0041] Example 2
[0042] A method for preparing 2,2-dialkoxymethyl-5-alkoxymethylfuran includes the following steps:
[0043] Step 1: Add 0.5g of the biomass platform compound 5-hydroxymethylfurfural and 5-sulfosalicylic acid to 12mL of isopropanol at a mass ratio of 1:0.033, and stir at 130℃ for 6h to obtain reaction solution A;
[0044] Step 2: Separate the catalyst from reaction solution A obtained in Step 1, and then continue to add NiZrPOx / SiO2 catalyst with a mass ratio of 1:0.167 to 5-hydroxymethylfurfural to the reaction solution. Reflux and remove water at 140℃ for 8 hours. After filtering out the catalyst, reaction solution B is obtained. Adjust the pH of reaction solution B to 7.5, and remove the solvent by vacuum distillation to obtain 2,2-bisisopropoxymethyl-5-isopropoxymethylfuran with a yield of 68.2%.
[0045] Example 3
[0046] A method for preparing 2,2-dialkoxymethyl-5-alkoxymethylfuran includes the following steps:
[0047] Step 1: Add 0.5g of the biomass platform compound 5-hydroxymethylfurfural and 5-sulfosalicylic acid to 6mL of isopropanol at a mass ratio of 1:2, and stir at 70℃ for 30min to obtain reaction solution A;
[0048] Step 2: Separate the catalyst from the reaction solution obtained in Step 1, and then continue to add NiZrPOx / SiO2 catalyst with a mass ratio of 1:2.33 to 5-hydroxymethylfurfural to the reaction solution. Reflux and remove water at 80℃ for 3 hours. After filtering out the catalyst, reaction solution B is obtained. Adjust the pH of reaction solution B to 8.5, and remove the solvent by vacuum distillation to obtain 2,2-bisisopropoxymethyl-5-isopropoxymethylfuran with a yield of 55.9%.
[0049] Example 4
[0050] A method for preparing 2,2-dialkoxymethyl-5-alkoxymethylfuran includes the following steps:
[0051] Step 1: Add 0.25g of the biomass platform compound 5-hydroxymethylfurfural and p-toluenesulfonic acid to 25mL of isopropanol at a mass ratio of 1:1.06, and stir the mixture at 100℃ for 4.5h to obtain reaction solution A;
[0052] Step 2: Separate the catalyst from the reaction solution obtained in Step 1, and then continue to add NiZrPOx / SiO2 catalyst with a mass ratio of 1:0.33 to 5-hydroxymethylfurfural to the reaction solution. Reflux and remove water at 110℃ for 5 h. After filtering out the catalyst, reaction solution B is obtained. Adjust the pH of reaction solution B to 8.0, and remove the solvent by vacuum distillation to obtain 2,2-bisisopropoxymethyl-5-isopropoxymethylfuran with a yield of 73.2%.
[0053] Example 5
[0054] A method for preparing 2,2-dialkoxymethyl-5-alkoxymethylfuran includes the following steps:
[0055] Step 1: Add 0.5g of the biomass platform compound 5-hydroxymethylfurfural and the carbon-based solid acid catalyst to 6mL of isopropanol at a mass ratio of 1:1, and stir the reaction at 90℃ for 3h to obtain reaction solution A;
[0056] Step 2: Separate the catalyst from the reaction solution obtained in Step 1, and then continue to add NiZrPOx / SiO2 catalyst with a mass ratio of 1:0.33 to 5-hydroxymethylfurfural to the reaction solution. Reflux and remove water at 110℃ for 5 h. After filtering out the catalyst, reaction solution B is obtained. Adjust the pH of reaction solution B to 8.0, and remove the solvent by vacuum distillation to obtain 2,2-bisisopropoxymethyl-5-isopropoxymethylfuran with a yield of 81.5%.
[0057] Example 6
[0058] A method for preparing 2,2-dialkoxymethyl-5-alkoxymethylfuran includes the following steps:
[0059] Step 1: Add 0.5g of the biomass platform compound 5-hydroxymethylfurfural and 5-sulfosalicylic acid catalyst to 12mL of methanol at a mass ratio of 1:0.033, and stir the reaction at 70℃ for 5h to obtain reaction solution A;
[0060] Step 2: Separate the catalyst from the reaction solution obtained in Step 1, and then continue to add NiZrPOx / SiO2 catalyst with a mass ratio of 1:0.167 to 5-hydroxymethylfurfural to the reaction solution. Reflux and remove water at 80℃ for 3 hours. After filtering out the catalyst, reaction solution B is obtained. Adjust the pH of reaction solution B to 7.5, and remove the solvent by vacuum distillation to obtain 2,2-dimethoxymethyl-5-methoxymethylfuran with a yield of 90.1%.
[0061] Example 7
[0062] A method for preparing 2,2-dialkoxymethyl-5-alkoxymethylfuran includes the following steps:
[0063] Step 1: Add 0.5g of the biomass platform compound 5-hydroxymethylfurfural and the solid acid catalyst to 12mL of methanol at a mass ratio of 1:0.5, and stir the reaction at 70℃ for 5h to obtain reaction solution A;
[0064] Step 2: Separate the catalyst from the reaction solution obtained in Step 1, and then continue to add NiZrPOx / SiO2 catalyst with a mass ratio of 1:0.167 to 5-hydroxymethylfurfural to the reaction solution. Reflux and remove water at 80℃ for 3 hours. After filtering out the catalyst, reaction solution B is obtained. Adjust the pH of reaction solution B to 8.5, and remove the solvent by vacuum distillation to obtain 2,2-dimethoxymethyl-5-methoxymethylfuran with a yield of 63.0%.
[0065] Figure 1 This describes the catalytic conversion pathway of 5-hydroxymethylfurfural in alcohol solvents. It can undergo various types of reactions with alcohol solvents under catalysis. To obtain its specific product with high selectivity, it is necessary to design the corresponding reaction pathway and precise catalyst sites.
[0066] Figure 2 The mass spectrometry results show that 2,2-dialkoxymethyl-5-alkoxymethylfuran products can be effectively prepared using this method.
[0067] This invention provides a method for preparing 2,2-dialkoxymethyl-5-alkoxymethylfuran, which efficiently and selectively converts the biomass platform compound 5-hydroxymethylfurfural into a high-energy-density alkoxyfuran compound in a two-step process. This method holds promise for the mass production of 2,2-dialkoxymethyl-5-alkoxymethylfuran products and their application in research on bio-based fuels or additives.
[0068] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.
Claims
1. A process for the preparation of 2,2-bisalkoxymethyl-5-alkoxymethylfuran, characterized in that, The method comprises the following steps: S1: mixing a biomass platform compound, a Brønsted acidic catalyst and an alcohol solvent, stirring to react, and obtaining a reaction liquid A; S2: adding a NiZrPOx / SiO2 catalyst into the reaction liquid, and reacting under the conditions of heating reflux and water removal to obtain a reaction liquid B; then adjusting the pH value of the reaction liquid B, and obtaining 2,2-bisalkoxymethyl-5-alkoxymethylfuran after removing the solvent by vacuum distillation; In S1, the biomass platform compound is 5-hydroxymethylfurfural; the Brønsted acidic catalyst is 5-sulfosalicylic acid or p-toluenesulfonic acid; In S2, the preparation method of the NiZrPOx / SiO2 catalyst is as follows: tetraethyl orthosilicate, nickel acetate, zirconium oxychloride, diammonium hydrogen phosphate, tetrapropylammonium hydroxide and acetylacetone are mixed in an alcohol-water mixed solvent according to a mass ratio of 1:0.206:0.053:0.16:1:0.33, then hydrothermal treatment is performed at 180 ℃ for 24 h, and calcination is performed at 600 ℃ for 3 h to obtain the catalyst.
2. A process for the preparation of 2,2-bisalkoxymethyl-5-alkoxymethylfuran according to claim 1, characterized in that, In S1, the alcohol solvent is methanol or isopropanol.
3. A process for the preparation of 2,2-bisalkoxymethyl-5-alkoxymethylfuran according to claim 1, characterized in that, In S1, the biomass platform compound, the Brønsted acidic catalyst and the alcohol solvent are used in a ratio of 1 g:(0.033-2) g:(12-60) mL.
4. A process for the preparation of 2,2-bisalkoxymethyl-5-alkoxymethylfuran according to claim 1, characterized in that, In S1, the reaction time is 30 min-6 h, and the reaction temperature is 70 ℃-130 ℃.
5. The process for the preparation of 2,2-bisalkoxymethyl-5-alkoxymethylfuran according to claim 1, characterized in that, In S2, the mass ratio of the NiZrPOx / SiO2 catalyst to the biomass platform compound is 0.167-2.
33.
6. A process for the preparation of 2,2-bisalkoxymethyl-5-alkoxymethylfuran according to claim 1, characterized in that, In S2, the pH value of the reaction liquid B is adjusted to 7.5-8.
5.
7. A process for the preparation of 2,2-bisalkoxymethyl-5-alkoxymethylfuran according to claim 1, characterized in that, In S2, the reaction time is 3 h-8 h, and the reaction temperature is 80 ℃-140 ℃.