CN116655566A - A method for synthesizing 2,5-furandicarboxylic acid in one step from 2,5-furandicarbaldehyde without oxygen participation - Google Patents

Abstract

The invention relates to a method for synthesizing 2,5-furandicarboxylic acid in one step from 2,5-furandicarbaldehyde without the participation of oxygen. The method comprises the following steps: adding 2,5-furandicarbaldehyde, ionic liquid, hydroxylamine salt and solvent into a closed reactor under a nitrogen atmosphere, and reacting at 60-150° C. for 2-9 hours under mechanical stirring to obtain the product 2 ,5‑furandicarboxylic acid. The invention does not use oxygen as an oxidant, and has intrinsic safety; does not use a noble metal catalyst, and reduces cost; the target product has high selectivity and simple separation; the ionic liquid is easy to recover and recycle, and the like.

Description

One-step synthesis of 2,5-furandicarboxylic acid from 2,5-furandicarbaldehyde without oxygen Methods

technical field

The invention belongs to the field of biomass conversion and preparation of chemicals, and specifically relates to a method for preparing 2,5-furandicarboxylic acid from 2,5-furandicarbaldehyde.

Background technique

2,5-furandicarboxylic acid (FDCA) is one of the most promising compounds among furan derivatives, and is rated as one of the twelve biological platform molecules with the most research value by the American Chemical Society (Polymer Chemistry, 2010, 1 (3):245-251). FDCA can be used to produce various biochemical substances. Because of its similar structure to terephthalic acid, it is often used as a renewable and green substitute for terephthalic acid for the synthesis of bio-based polyesters, nylon and other high-performance polymers and Novel biodegradable copolyesters. In addition, FDCA can also be used to produce petroleum-based polymer modifiers such as degradable plastics and unsaturated resins (RS Cadvances, 2018, 8(6):3161-3177).

Currently, FDCA is mainly prepared by oxidation of 5-hydroxymethylfurfural (HMF). Most of these catalytic systems require pure oxygen or air as an oxidant, and noble metals (such as gold, platinum, palladium and ruthenium) or non-noble metals (such as manganese, cobalt and cerium) as catalysts (Industrial & Engineering Chemistry Research, 2020, 59(11): 4895 -4904; ChemSusChem, 2019, 12(12):2715-2724). Han et al. used Pt/C–O–Mg as a catalyst to react at 10 bar O ₂ at 110°C for 12 h, and the yield of FDCA was 97% (Green Chemistry, 2016, 18(6):1597-1604). Guan et al. used Au ₁ Pd ₁ /pBNC-30%HNO ₃ as a catalyst, reacted at 2MPa O ₂ , 100°C for 20h, and the yield of FDCA was 93.9% (ChemSusChem, 2022, 15(16):e202201041). Although the yield of FDCA is above 90%, it faces the following problems: incomplete oxidation of HMF produces a large number of partially oxidized intermediates, such as 5-formyl-2-furancarboxylic acid (FFCA) and 5-hydroxymethyl-2-furancarboxylic acid (HMFCA), reducing target product selectivity and atom economy; using oxygen as an oxidant has safety hazards such as flammability and explosion; FDCA has low solubility in conventional solvents, and the use of solid catalysts leads to difficulties in product separation.

In summary, the present invention proposes for the first time a sustainable and safe process route for the direct catalytic synthesis of FDCA from the downstream bio-based raw material 2,5-furandicarbaldehyde (DFF) in the absence of oxygen and metal catalysts in one step. In order to eliminate the potential safety hazards in the reaction.

Contents of the invention

The purpose of the present invention is to provide a kind of 2,5 without the participation of oxygen in order to solve the shortcomings of the current technology that use oxygen as the oxidant to produce partially oxidized intermediates, which have safety hazards such as inflammability and explosion, and use solid catalysts to cause product separation difficulties. - One-step synthesis of 2,5-furandicarboxylic acid from furandicarbaldehyde. The method uses ionic liquid as a catalyst instead of a traditional metal catalyst to catalyze a green new process of synthesizing FDCA in the next step from sustainable raw material DFF under anaerobic conditions. The invention does not use oxygen as an oxidant, and has intrinsic safety; does not use a noble metal catalyst, and reduces cost; the target product has high selectivity and simple separation; the ionic liquid is easy to recover and recycle, and the like.

Technical scheme of the present invention is:

A method for the one-step synthesis of 2,5-furandicarboxylic acid from 2,5-furandicarbaldehyde without oxygen participation, the method comprising the following steps:

Add 2,5-furandicarbaldehyde, ionic liquid, hydroxylamine salt and solvent into a closed reactor under a nitrogen atmosphere, react at 60-150°C for 2-9 hours under mechanical stirring, and directly obtain the product 2,5- furandicarboxylic acid;

Among them, the molar ratio of materials is: for every 1mmol of 2,5-furandicarbaldehyde, add 0.6-6g of ionic liquid, 1-8mmol of hydroxylamine salt, and 1-10mL of solvent;

The ionic liquid is 1-sulfobutyl-3-methylimidazole hydrogen sulfate, 1-sulfobutyl-3-methylimidazole trifluoromethanesulfonate, 1-sulfobutyl-3-methylimidazole p-toluenesulfonate, 1-butyl-3-methylimidazolium bisulfate, 1-sulfobutyl-3-methylimidazolium iodide, N,N,N-trimethyl-N-sulfobutylsulfate Hydrogen ammonium salt, N,N,N-Trimethyl-N-sulfobutyl trifluoromethanesulfonate, N,N,N-Trimethyl-N-sulfobutyl p-toluenesulfonate, 1-sulfo One or more of butylpyridine bisulfate, 1-sulfobutylpyridine trifluoromethanesulfonate and 1-sulfobutylpyridine p-toluenesulfonate;

The hydroxylamine salt is hydroxylamine hydrochloride, hydroxylamine sulfate, 1-sulfobutyl-3-methylimidazolium hydrogensulfate ionic liquid type hydroxylamine salt, 1-sulfobutylpyridine hydrogensulfate ionic liquid type hydroxylamine salt or N,N , N-trimethyl-N-sulfobutyl ammonium bisulfate ionic liquid type hydroxylamine salt.

The solvent is one or two of water, tetrahydrofuran, ethanol or p-xylene.

The reactor is a high-pressure reactor.

The ratio of the materials is preferably 0.6-3.6 g of ionic liquid, 2-6 mmol of hydroxylamine salt, and 3-6 mL of solvent per 1 mmol of 2,5-furandicarbaldehyde.

The preferred reaction temperature is 80-140°C.

The preferred reaction time is 4-8 hours.

Substantive features of the present invention are:

All references in the current art for the synthesis of FDCA are via oxidative routes.

The present invention does not use oxygen and metal catalysts, adopts ionic liquids as catalysts, and synthesizes 2,5-furandicarboxylic acid in the next step under anaerobic conditions.

The beneficial effects of the present invention are:

(1) The present invention realizes for the first time the one-step synthesis of 2,5-furandicarboxylic acid from 2,5-furandicarbaldehyde under anaerobic conditions, the reaction process is short, the raw materials are sustainable, and the product separation yield can reach 91.0%.

(2) Oxygen and metal catalysts are not used, and it is intrinsically safe.

(3) The ionic liquid is used instead of the metal catalyst, which is more green, and the ionic liquid is soluble in water, which is convenient for the recovery of the ionic liquid and has good cycle performance.

(4) After the reaction, FDCA crystallizes out, and the separation of the product is simple, which has important industrial application value.

Detailed ways:

The essential features and remarkable effects of the present invention can be embodied from the following examples, but they do not limit the present invention in any way, and those skilled in the art can make some non-essential improvements and adjustments according to the contents of the present invention. The present invention will be further described below through specific embodiments.

The ionic liquid involved in the present invention is a known material, and the composition of the ionic liquid includes cations and anions. The following is the preparation method of 1-sulfobutyl-3-methylimidazolium bisulfate ionic liquid ([HSO ₃ -b-mim]·HSO ₄ ):

Weighed equimolar N-methylimidazole and 1,4-butane sultone into a 250mL three-neck flask, reacted in a water bath at 40°C for 12h, distilled off the water under reduced pressure to obtain the precursor of the ionic liquid, and then used Water, ethanol, toluene and ether were washed several times to remove unreacted raw materials and impurities, and then the washed precursor was dried overnight in a vacuum oven at 80°C. Then weigh equimolar precursors and concentrated sulfuric acid and add them to a 100mL three-neck flask, and react in a water bath at 80°C for 6h to obtain a colorless transparent liquid, which is then washed several times with absolute ethanol, toluene and ether, and placed in a vacuum at 80°C Oven dried overnight to obtain [HSO ₃ -b-mim]·HSO ₄ . The preparation process of other ionic liquids is the same as above.

The preparation process of ionic liquid-type hydroxylamine salt is as follows, taking 1-sulfobutyl-3-methylimidazolium bisulfate ionic liquid-type hydroxylamine salt as an example: Weigh 0.25mol of hydroxylamine sulfate into 100mL of distilled water, and stir until completely dissolved. The above-mentioned hydroxylamine sulfate aqueous solution was placed in a low temperature and constant temperature reactor at -2°C, and 40 g of NaOH solution with a mass percentage of 50% was added dropwise under stirring; after the addition was completed, the stirring reaction was continued for 5 minutes, and stood still for 5 minutes. Remove the generated sodium sulfate by filtration, add stabilizer ascorbic acid to the filtrate, distill under reduced pressure at 52°C, the distillate is free NH ₂ OH aqueous solution. Then, under the condition of constant stirring at -2°C, the free NH ₂ OH aqueous solution was slowly added dropwise to the above-mentioned ionic liquid. During this process, the reaction temperature was strictly controlled not to exceed 4°C, and the stirring was continued for 2 hours after the dropwise addition was completed. After the reaction is completed, water is removed by rotary evaporation to obtain 1-sulfobutyl-3-methylimidazolium bisulfate ionic liquid hydroxylamine salt. The preparation process of other ionic liquid type hydroxylamine salts is the same as above.

Example 1

Add 2,5-furandicarbaldehyde (1mmol), hydroxylamine hydrochloride (2mmol), water (6mL) and [HSO ₃ -b-mim]·HSO ₄ (0.6g) into the autoclave, seal it and pass in N ₂ The air in the reactor was replaced, the air in the reactor was evacuated, and the reaction was stopped after mechanical stirring at 140° C. for 8 hours. The reaction solution is poured into ice water, the ionic liquid is dissolved in water and is in the water phase, and the product sinks to the bottom. After it is filtered, the water phase containing the ionic liquid is subjected to rotary evaporation to remove water, and the recovered ionic liquid is obtained; The product is washed, dried and weighed to calculate its separation yield. The reaction result is that the conversion rate of DFF is 100%, and the yield of FDCA is 77.4%.

Example 2

Other steps were the same as in Example 1, except that 1.8 g of [HSO ₃ -b-mim]·HSO ₄ was added. The conversion of DFF was 100%, and the yield of FDCA was 81.1%.

Example 3

Other steps are the same as in Example 1, except that 3.6 g of [HSO ₃ -b-mim]·HSO ₄ is added. The conversion of DFF was 100%, and the yield of FDCA was 87.8%.

Example 4

Other steps are the same as in Example 1, except that 6.0 g of [HSO ₃ -b-mim]·HSO ₄ is added. The conversion of DFF was 100%, and the yield of FDCA was 68.9%.

Example 5

Other steps are the same as in Example 1, except that the hydroxylamine salt added is hydroxylamine sulfate. The conversion of DFF was 100%, and the yield of FDCA was 61.2%.

Example 6

Other steps are the same as in Example 1, except that the added hydroxylamine salt is 1-sulfobutyl-3-methylimidazolium bisulfate ionic liquid type hydroxylamine salt. The conversion of DFF was 100%, and the yield of FDCA was 45.8%.

Example 7

Other steps are the same as in Example 1, except that the added hydroxylamine salt is 1-sulfobutylpyridine bisulfate ionic liquid type hydroxylamine salt. The conversion of DFF was 100%, and the yield of FDCA was 43.6%.

Example 8

Other steps are the same as in Example 1, except that the added hydroxylamine salt is N,N,N-trimethyl-N-sulfobutylammonium bisulfate ionic liquid type hydroxylamine salt. The conversion of DFF was 100%, and the yield of FDCA was 41.6%.

Example 9

Other steps are the same as in Example 1, except that the added hydroxylamine hydrochloride is 1 mmol. The DFF conversion was 100%, and the FDCA yield was 10.1%.

Example 10

Other steps are the same as in Example 1, except that the added hydroxylamine hydrochloride is 6 mmol. The conversion of DFF was 100%, and the yield of FDCA was 80.3%.

Example 11

Other steps are the same as in Example 1, except that the added hydroxylamine hydrochloride is 8 mmol. The conversion of DFF was 100%, and the yield of FDCA was 74.3%.

Example 12

Other steps are the same as in Example 1, except that the added ionic liquid is 1-sulfobutyl-3-methylimidazolium trifluoromethanesulfonate. The conversion of DFF was 100%, and the yield of FDCA was 59.6%.

Example 13

Other steps are the same as in Example 1, except that the added ionic liquid is 1-sulfobutyl-3-methylimidazole p-toluenesulfonate. The conversion of DFF was 100%, and the yield of FDCA was 39.7%.

Example 14

Other steps are the same as in Example 1, except that the added ionic liquid is 1-sulfobutyl-3-methylimidazolium iodide. The conversion of DFF was 100%, and the yield of FDCA was 36.5%.

Example 15

Other steps are the same as in Example 1, except that the added ionic liquid is 1-butyl-3-methylimidazolium bisulfate. The conversion of DFF was 100%, and the yield of FDCA was 19.6%.

Example 16

Other steps are the same as in Example 1, except that the added ionic liquid is N,N,N-trimethyl-N-sulfobutylammonium hydrogensulfate. The conversion of DFF was 100%, and the yield of FDCA was 62.2%.

Example 17

Other steps are the same as in Example 1, except that the added ionic liquid is N,N,N-trimethyl-N-sulfobutyl trifluoromethanesulfonate. The conversion of DFF was 100%, and the yield of FDCA was 72.3%.

Example 18

Other steps are the same as in Example 1, except that the added ionic liquid is N,N,N-trimethyl-N-sulfobutyl p-toluenesulfonate. The conversion of DFF was 100%, and the yield of FDCA was 53.6%.

Example 19

Other steps are the same as in Example 1, except that the added ionic liquid is 1-sulfobutylpyridine hydrogensulfate. The conversion of DFF was 100%, and the yield of FDCA was 35.9%.

Example 20

Other steps are the same as in Example 1, except that the added ionic liquid is 1-sulfobutylpyridine trifluoromethanesulfonate. The conversion of DFF was 100%, and the yield of FDCA was 47.8%.

Example 21

Other steps are the same as in Example 1, except that the added ionic liquid is 1-sulfobutylpyridine p-toluenesulfonate. The conversion of DFF was 100%, and the yield of FDCA was 69.6%.

Example 22

Other steps are the same as in Example 1, except that the reaction time is 2h. The DFF conversion was 100%, and the FDCA yield was 17.2%.

Example 23

Other steps are the same as in Example 1, except that the reaction time is 4h. The conversion of DFF was 100%, and the yield of FDCA was 58.3%.

Example 24

Other steps are the same as in Example 1, except that the reaction time is 9h. The DFF conversion was 100%, and the FDCA yield was 59.7%.

Example 25

Other steps are the same as in Example 1, except that the reaction temperature is 60°C. The conversion of DFF was 100%, and the yield of FDCA was 9.7%.

Example 26

Other steps are the same as in Example 1, except that the reaction temperature is 80°C. The DFF conversion was 100%, and the FDCA yield was 39.4%.

Example 27

Other steps are the same as in Example 1, except that the reaction temperature is 150°C. The DFF conversion was 100%, and the FDCA yield was 58.6%.

Example 28

Other steps are the same as in Example 1, except that the added solvent is tetrahydrofuran. The conversion of DFF was 100%, and the yield of FDCA was 32.7%.

Example 29

Other steps are the same as in Example 1, except that the added solvent is ethanol. The conversion of DFF was 100%, and the yield of FDCA was 25.9%.

Example 30

Other steps are the same as in Example 1, except that the added solvent is p-xylene. The conversion of DFF was 100%, and the yield of FDCA was 57.3%.

Example 31

Other steps are the same as in Example 1, except that the added solvent is water: p-xylene=1:2 (V:V). The conversion of DFF was 100%, and the yield of FDCA was 91.0%.

Example 32

The other steps are the same as in Example 1, except that the number of times the ionic liquid is reused is 5 times. The conversion of DFF was 100%, and the yield of FDCA was 75.4%.

It can be seen from the above examples that DFF can react with hydroxylamine in one step to generate FDCA under oxygen-free conditions. In this reaction, oxygen is not needed, which solves the risk of flammability and explosion in traditional oxidation methods and is intrinsically safe. and the catalytic system of the present invention is simple to operate, and the yield of FDCA is high; the preparation process of the ionic liquid used is simple, the cycle is good, and it has important industrial application value.

The above are only some specific examples of the present invention, but the protection scope of the present invention is not limited thereto, nor does the order of the various embodiments cause any limitation to the present invention. Within the technical scope of the report, changes or substitutions can be easily made, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention is not limited to the above embodiments, and should be based on the protection scope of the claims.

Matters not covered in the present invention are known technologies.

Claims (6)

1. The method for synthesizing 2, 5-furandicarboxylic acid by one step from 2, 5-furandicarboxaldehyde without oxygen participation is characterized by comprising the following steps:

adding 2, 5-furan dicarboxaldehyde, ionic liquid, hydroxylamine salt and solvent into a closed reactor under nitrogen atmosphere, reacting for 2-9 h at 60-150 ℃ under mechanical stirring, and directly obtaining the product 2, 5-furan dicarboxylic acid through one-step reaction;

wherein, the molar ratio of the materials is as follows: adding 0.6-6 g of ionic liquid, 1-8 mmol of hydroxylamine salt and 1-10 mL of solvent into each 1mmol of 2, 5-furan dicarboxaldehyde;

the ionic liquid is one or more of 1-sulfobutyl-3-methylimidazole bisulfate, 1-sulfobutyl-3-methylimidazole trifluoromethanesulfonate, 1-sulfobutyl-3-methylimidazole p-toluenesulfonate, 1-butyl-3-methylimidazole bisulfate, 1-sulfobutyl-3-methylimidazole iodized salt, N, N, N-trimethyl-N-sulfobutyl hydrogen ammonium sulfate salt, N, N, N-trimethyl-N-sulfobutyl trifluoromethanesulfonate, N, N, N-trimethyl-N-sulfobutyl p-toluenesulfonate, 1-sulfobutylpyridine bisulfate, 1-sulfobutylpyridine trifluoromethanesulfonate and 1-sulfobutylpyridine p-toluenesulfonate;

the hydroxylamine salt is hydroxylamine hydrochloride, hydroxylamine sulfate, 1-sulfobutyl-3-methylimidazole bisulfate ionic liquid hydroxylamine salt, 1-sulfobutyl pyridine bisulfate ionic liquid hydroxylamine salt or N, N, N-trimethyl-N-sulfobutyl hydrogen sulfate ammonium salt ionic liquid hydroxylamine salt.

2. The method for synthesizing 2, 5-furandicarboxylic acid in one step from 2, 5-furandicarboxaldehyde without participation of oxygen according to claim 1, wherein the solvent is one or two of water, tetrahydrofuran, ethanol and paraxylene.

3. The method for synthesizing 2, 5-furandicarboxylic acid in one step by using 2, 5-furandicarboxaldehyde without participation of oxygen according to claim 1, wherein the reactor is a high-pressure reactor.

4. The method for synthesizing 2, 5-furandicarboxylic acid by one step of 2, 5-furandicarboxaldehyde without participation of oxygen according to claim 1, wherein the material proportion is that 0.6-3.6 g of ionic liquid, 2-6 mmol of hydroxylamine salt and 3-6 mL of solvent are added to 1mmol of 2, 5-furandicarboxaldehyde.

5. The method for synthesizing 2, 5-furandicarboxylic acid in one step from 2, 5-furandicarboxaldehyde without participation of oxygen according to claim 1, wherein the reaction temperature is 80-140 ℃.

6. The method for synthesizing 2, 5-furandicarboxylic acid by one step without participation of oxygen in 2, 5-furandicarboxaldehyde according to claim 1, wherein the reaction time is 4-8 h.