CN111825643A - A kind of preparation method of 2,5-dicyanofuran - Google Patents

Abstract

The present application discloses a method for preparing 2,5-dicyanofuran. In the presence of an oxidant, a mixture containing 2,5-diformylfuran, a nitrogen source and a catalyst is reacted to obtain 2,5-dicyanofuran. Cyanofuran; wherein the catalyst comprises a metal oxide modified with an organic compound. The present application provides a method for the preparation of 2,5-dicyanofuran by efficient catalytic ammoxidation of 2,5-diformylfuran. Under mild conditions, high-selectivity ammoxidation of 2,5-diformylfuran is used to prepare high-quality 2,5-diformylfuran. , 5-dicyanofuran. The application has high oxidation efficiency and high product yield; air or oxygen is used as oxygen source, ammonium salt is used as nitrogen source, nitrogen source utilization rate is high, clean and environmentally friendly; product and catalyst are easy to separate, post-processing is simple, and has good application prospects .

Description

A kind of preparation method of 2,5-dicyanofuran

technical field

The application relates to a preparation method of 2,5-dicyanofuran, which belongs to the technical field of chemical product preparation.

Background technique

Dibasic nitriles are an important class of chemical intermediates with a wide range of uses. Its derivative diamine shows unique and excellent properties in dyes, medicines, curing agents and high molecular polymers. At present, binary nitriles are mainly prepared by gas-phase ammoxidation of hydrocarbons, the reaction conditions are harsh, and the production process has high safety and environmental protection costs. In contrast, starting from bio-based aldols, nitriles can be prepared by liquid-phase ammoxidation under mild conditions. It is of great significance to develop the synthetic route of bio-based dibasic nitriles for increasing the added value of bio-based chemicals, alleviating and partially replacing non-renewable fossil resources.

Dehydration and oxidation of carbohydrates can yield biological and platform compounds 2,5-diformylfuran (DFF). The aldehyde group in DFF can realize catalytic ammonia oxidation under mild conditions. However, DFF easily undergoes an irreversible polycondensation reaction with ammonia; on the other hand, there is a strong electron-withdrawing effect between the two cyano groups in the 2,5-dicyanofuran generated by the reaction, which is in the acid-base active site of the catalyst. Under the action of point activation, the cyano group is easily further hydrolyzed to form an amide. How to improve the selectivity of DFF ammoxidation to form dibasic nitriles still faces great challenges.

SUMMARY OF THE INVENTION

According to one aspect of the present application, a method for preparing 2,5-dicyanofuran from 2,5-diformylfuran is provided, and the method has high oxidation efficiency and high product yield.

A method for preparing 2,5-dicyanofuran, characterized in that in the presence of an oxidant, a mixture containing 2,5-diformylfuran, a nitrogen source and a catalyst is reacted to obtain 2,5-dicyanofuran cyanofuran;

Wherein, the catalyst includes a metal oxide modified by an organic compound.

The present application provides a method for catalyzing ammonia oxidation of 2,5-diformylfuran to prepare 2,5-dicyanofuran, using ammonium salt as nitrogen source, using air or oxygen as oxidant, in the role of organic modified metal oxide catalyst Next, 2,5-diformylfuran is oxidized to 2,5-dicyanofuran by highly selective ammoxidation.

Optionally, the organic compound and the metal oxide are put into a solvent, and then 2,5-diformylfuran and a nitrogen source are added to react in the presence of an oxidant to obtain 2,5-dicyanofuran.

Optionally, the organic compound includes acetylacetone, 3-methylacetylacetone, 1,1,1-trifluoroacetylacetone, hexafluoroacetylacetone, N,N-dimethylcyclohexylamine, N-methylacetylacetone At least one of piperidine, N-methyltetrahydropyrrole, and proline.

Optionally, the metal oxide includes at least one of manganese oxide, cobalt oxide, and nickel oxide.

Specifically, the cobalt oxide is at least one of Co ₃ O ₄ and CoO.

The oxide of nickel is NiO.

Preferably, the manganese oxide includes at least one of amorphous manganese dioxide, α-MnO ₂ , β-MnO ₂ , γ-MnO ₂ , and δ-MnO ₂ .

Optionally, the metal oxide is at least one of amorphous manganese dioxide, α-MnO ₂ , β-MnO ₂ , γ-MnO ₂ , δ-MnO ₂ , NiO, Co ₃ O ₄ , and CoO.

Optionally, the mole number of the organic compound is 0.5-5% of the mole number of 2,5-diformylfuran.

The upper limit of the percentage of moles of organic compounds to moles of 2,5-diformylfuran is selected from 1%, 2%, 3%, 4% or 5%; The lower limit of the percentage of furan moles is selected from 0.5%, 1%, 2%, 3% or 4%.

Optionally, the amount of the catalyst used is 5-20 mol% of 2,5-diformylfuran;

Wherein, the number of moles of the catalyst is calculated as the number of moles of the metal oxide.

The upper limit of the percentage of the moles of the catalyst to the moles of 2,5-diformylfuran is selected from 10%, 15% or 20%; the lower limit of the percentage of the moles of the catalyst to the moles of 2,5-diformylfuran is selected from From 5%, 10% or 15%.

Optionally, the molar ratio of the nitrogen source to 2,5-diformylfuran is 1-9:1;

The number of moles of the nitrogen source is calculated by the number of moles of the nitrogen source itself.

Optionally, the nitrogen source is selected from at least one of ammonium salts.

Preferably, the ammonium salt is selected from at least one of ammonium formate, ammonium acetate, ammonium oxalate, ammonium carbonate, ammonium bicarbonate, and ammonium phosphate.

Optionally, the molar ratio of the ammonium salt to 2,5-diformylfuran is 1-9:1.

Optionally, the oxidant comprises an oxygen-containing atmosphere.

Optionally, the oxygen partial pressure of the oxygen-containing atmosphere is 0.1-5 MPa.

Preferably, the oxygen-containing atmosphere is selected from oxygen or air.

The upper pressure limit of the oxygen-containing atmosphere is selected from 0.5MPa, 1MPa, 2MPa, 3MPa or 5MPa; the lower pressure limit of the oxygen-containing atmosphere is selected from 0.1MPa, 0.5MPa, 1MPa, 2MPa or 3MPa.

Optionally, the conditions of the reaction are: the reaction temperature is 30-120° C.; the reaction time is 0.5-48 h.

In this application, the upper limit of the reaction temperature is selected from 60°C, 70°C, 80°C, 90°C or 120°C; the lower limit of the reaction temperature is selected from 30°C, 60°C, 70°C, 80°C or 90°C.

The upper limit of the reaction time is selected from 5h, 6h, 8h, 12h, 48h; the lower limit of the reaction time is selected from 0.5h, 5h, 6h, 8h, 12h.

Optionally, the mixture also includes a solvent;

The solvent includes any one of acetonitrile, dioxane, tert-butanol, tert-amyl alcohol, toluene, and p-xylene.

Optionally, the preparation method of the catalyst includes: drawing on the technology reported by the present inventor (Nature Commun., 2018, 9:933), putting the metal oxide and the organic compound into a reaction vessel, adding a solvent, and at 25-35 Stir at ℃ for 70-75 h to modify the organic compound on the metal oxide to obtain the catalyst.

After preparing the catalyst, add 2,5-diformylfuran, nitrogen source, fill with air or oxygen, and react to obtain 2,5-dicyanofuran.

A better preparation method is described below:

During the specific operation, the metal oxide and the organic modified molecule (ie, organic compound) were put into a 20 mL lined reaction kettle, the solvent was added, and the mixture was stirred at 30 °C for 72 h. After the modification was completed, 2,5-diformylfuran and Ammonium salt, fill with air or oxygen, program the temperature to 30-120°C and react for 0.5-48h, 2,5-diformylfuran is ammoxidized to 2,5-dicyanofuran.

Optionally, separation and purification are carried out after the reaction to obtain 2,5-dicyanofuran.

Specifically, for the purification of 2,5-dicyanofuran, the reaction mixture was cooled to room temperature, the catalyst was removed by centrifugation, the solvent was removed by rotary evaporation, water was added, then ethyl acetate was added for extraction, the solvent was removed by rotary evaporation, vacuum dried, and weighed Calculate the separation yield.

The beneficial effects that this application can produce include:

The application provides a method for efficiently catalyzing ammoxidation of 2,5-diformylfuran to prepare 2,5-dicyanofuran. Quality 2,5-dicyanofuran. The application has high oxidation efficiency and high product yield; air or oxygen is used as oxygen source, ammonium salt is used as nitrogen source, nitrogen source utilization rate is high, clean and environmentally friendly; product and catalyst are easy to separate, post-processing is simple, and has good application prospects .

Detailed ways

The present application will be described in detail below with reference to the examples, but the present application is not limited to these examples.

Unless otherwise specified, the raw materials in the examples of this application are all purchased through commercial channels.

Conversion rate of 2,5-diformylfuran=(moles of converted 2,5-diformylfuran/moles of 2,5-diformylfuran in raw material)×100%; , The number of moles of 5-diformylfuran" is "the number of moles of 2,5-diformylfuran in the raw material-the number of moles of 2,5-diformylfuran in the product".

Selectivity of 2,5-dicyanofuran=(moles of 2,5-dicyanofuran produced/moles of converted 2,5-diformylfuran)×100%

The qualitative analysis of the product was carried out by gas chromatography-mass spectrometry, and the retention time of the product was compared with that of the standard sample; the quantitative analysis was carried out by the internal standard gas chromatography. Wherein, the standard sample refers to: 2,5-dicyanofuran (purity: >98%; source: Aladdin).

The model of the gas chromatograph was Agilent 7890A.

The model of the gas chromatograph mass spectrometer was Agilent 6890N GC/5973MS.

Example 1

Put 0.05mmol of amorphous manganese dioxide and 0.005mmol of acetylacetone into a 20mL lined reactor, add 10mL of acetonitrile, stir at 30°C for 72h, then add 1mmol of 2,5-diformylfuran and 2.4mmol of ammonium acetate, Filled with 0.1 MPa air, programmed the temperature to 30 °C and reacted for 48 h to obtain 2,5-dicyanofuran.

Then, the mixture was cooled to room temperature, the catalyst was removed by centrifugation, the solvent was removed by rotary evaporation, water was added, then ethyl acetate was added for extraction, the solvent was removed by rotary evaporation, vacuum dried at 40°C, and the separation yield was calculated by weighing.

The qualitative analysis of the obtained samples was performed by gas chromatography-mass spectrometry, and the quantitative analysis was performed by gas chromatography. The conversion of 2,5-diformylfuran was 80% and the selectivity to 2,5-dicyanofuran was 92%. The isolated yield of 2,5-dicyanofuran was 70%, and the gas chromatography purity was 99.1%.

Example 2

Put 0.1mmolα- _MnO and 0.01mmol 3-methylacetylacetone into a 20mL lined reactor, add 10mL dioxane, stir at 30°C for 72h, then add 1mmol 2,5-diformylfuran and 4.5 mmol of ammonium acetate was filled with 0.5 MPa of air, and the temperature was programmed to 60 °C and reacted for 12 h to obtain 2,5-dicyanofuran.

Then, the mixture was cooled to room temperature, the catalyst was removed by centrifugation, the solvent was removed by rotary evaporation, water was added, then ethyl acetate was added for extraction, the solvent was removed by rotary evaporation, vacuum dried at 40°C, and the separation yield was calculated by weighing.

The qualitative analysis of the obtained samples was performed by gas chromatography-mass spectrometry, and the quantitative analysis was performed by gas chromatography. The conversion of 2,5-diformylfuran was 91% and the selectivity to 2,5-dicyanofuran was 96%. The isolated yield of 2,5-dicyanofuran was 80%, and the gas chromatography purity was 99.0%.

Example 3

Put 0.2mmolβ-MnO ₂ and 0.03mmol 1,1,1-trifluoroacetylacetone into a 20mL lined reactor, add 10mL tert-butanol, stir at 30°C for 72h, then add 1mmol 2,5-dimethylacetone Acylfuran and 2.2mmol of ammonium formate were charged with 1MPa oxygen, and the temperature was programmed to 90°C for 6h to obtain 2,5-dicyanofuran.

Then, the mixture was cooled to room temperature, the catalyst was removed by centrifugation, the solvent was removed by rotary evaporation, water was added, then ethyl acetate was added for extraction, the solvent was removed by rotary evaporation, vacuum dried at 40°C, and the separation yield was calculated by weighing.

The qualitative analysis of the obtained samples was performed by gas chromatography-mass spectrometry, and the quantitative analysis was performed by gas chromatography. The conversion of 2,5-diformylfuran was 81% and the selectivity to 2,5-dicyanofuran was 94%. The isolated yield of 2,5-dicyanofuran was 65%, and the gas chromatography purity was 99.2%.

Example 4

Put 0.15mmol γ- _MnO and 0.05mmol hexafluoroacetylacetone into a 20mL lined reactor, add 10mL tert-amyl alcohol, stir at 30°C for 72h, then add 1mmol 2,5-diformylfuran and 3.9mmol acetic acid ammonium, filled with 2MPa air, and the temperature was programmed to 120 °C for 0.5 h to obtain 2,5-dicyanofuran.

Then, the mixture was cooled to room temperature, the catalyst was removed by centrifugation, the solvent was removed by rotary evaporation, water was added, then ethyl acetate was added for extraction, the solvent was removed by rotary evaporation, vacuum dried at 40°C, and the separation yield was calculated by weighing.

The qualitative analysis of the obtained samples was performed by gas chromatography-mass spectrometry, and the quantitative analysis was performed by gas chromatography. The conversion of 2,5-diformylfuran was 90% and the selectivity to 2,5-dicyanofuran was 95%. The isolated yield of 2,5-dicyanofuran was 75%, and the gas chromatography purity was 99.4%.

Example 5

Put 0.1mmolδ- _MnO and 0.02mmol N,N-dimethylcyclohexylamine into a 20mL lined reactor, add 10mL p-xylene, stir at 30°C for 72h, then add 1mmol 2,5-dimethylbenzene Acylfuran and 1.1mmol of ammonium oxalate were charged with 2MPa air, and the temperature was programmed to 80°C for 5h to obtain 2,5-dicyanofuran.

Then, the mixture was cooled to room temperature, the catalyst was removed by centrifugation, the solvent was removed by rotary evaporation, water was added, then ethyl acetate was added for extraction, the solvent was removed by rotary evaporation, vacuum dried at 40°C, and the separation yield was calculated by weighing.

The qualitative analysis of the obtained samples was performed by gas chromatography-mass spectrometry, and the quantitative analysis was performed by gas chromatography. The conversion of 2,5-diformylfuran was 83% and the selectivity to 2,5-dicyanofuran was 96%. The isolated yield of 2,5-dicyanofuran was 69%, and the gas chromatography purity was 99.7%.

Example 6

Add 0.1 mmol Co ₃ O ₄ and 0.01 mmol N-methylpiperidine to a 20 mL lined reactor, add 10 mL toluene, stir at 30°C for 72 h, then add 1 mmol 2,5-diformyl furan and 1.5 mmol Ammonium carbonate was charged with 3MPa air, and the temperature was programmed to 70 °C for 8 h to obtain 2,5-dicyanofuran.

Then, the mixture was cooled to room temperature, the catalyst was removed by centrifugation, the solvent was removed by rotary evaporation, water was added, then ethyl acetate was added for extraction, the solvent was removed by rotary evaporation, vacuum dried at 40°C, and the separation yield was calculated by weighing.

The qualitative analysis of the obtained samples was performed by gas chromatography-mass spectrometry, and the quantitative analysis was performed by gas chromatography. The conversion of 2,5-diformylfuran was 88% and the selectivity to 2,5-dicyanofuran was 98%. The isolated yield of 2,5-dicyanofuran was 73%, and the gas chromatography purity was 99.6%.

Example 7

Add 0.05 mmol NiO and 0.005 mmol N-methyltetrahydropyrrole to a 20 mL lined reactor, add 10 mL toluene, stir at 30°C for 72 h, then add 1 mmol 2,5-diformyl furan and 6 mmol ammonium bicarbonate , filled with 5MPa air, and the temperature was programmed to 70 °C for 8 h to obtain 2,5-dicyanofuran.

Then, the mixture was cooled to room temperature, the catalyst was removed by centrifugation, the solvent was removed by rotary evaporation, water was added, then ethyl acetate was added for extraction, the solvent was removed by rotary evaporation, vacuum dried at 40°C, and the separation yield was calculated by weighing.

The qualitative analysis of the obtained samples was performed by gas chromatography-mass spectrometry, and the quantitative analysis was performed by gas chromatography. The conversion of 2,5-diformylfuran was 65% and the selectivity to 2,5-dicyanofuran was 97%. The isolated yield of 2,5-dicyanofuran was 43%, and the gas chromatography purity was 99.1%.

Example 8

Add 0.05mmol CoO and 0.005mmol Proline to a 20mL lined reactor, add 10mL toluene, stir at 30°C for 72h, then add 1mmol 2,5-diformylfuran and 8mmol ammonium phosphate, fill with 5MPa air , and the temperature was programmed to 70 °C for 8 h to obtain 2,5-dicyanofuran.

Then, the mixture was cooled to room temperature, the catalyst was removed by centrifugation, the solvent was removed by rotary evaporation, water was added, then ethyl acetate was added for extraction, the solvent was removed by rotary evaporation, vacuum dried at 40°C, and the separation yield was calculated by weighing.

The qualitative analysis of the obtained samples was performed by gas chromatography-mass spectrometry, and the quantitative analysis was performed by gas chromatography. The conversion of 2,5-diformylfuran was 65% and the selectivity to 2,5-dicyanofuran was 97%. The isolated yield of 2,5-dicyanofuran was 43%, and the gas chromatography purity was 99.1%.

The present application provides a method for preparing 2,5-dicyanofuran by selective ammoxidation of 2,5-diformylfuran, the catalyst system is simple and efficient, the by-products are few, the catalyst and the product are easy to separate, and has a good application prospect.

The above are only a few embodiments of the present application, and are not intended to limit the present application in any form. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Without departing from the scope of the technical solution of the present application, any changes or modifications made by using the technical content disclosed above are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims (10)

1. A method for preparing 2, 5-dicyanofuran is characterized in that a mixture containing 2, 5-diformylfuran, a nitrogen source and a catalyst is reacted in the presence of an oxidant to obtain 2, 5-dicyanofuran;

wherein the catalyst comprises a metal oxide modified with an organic compound.

2. The method of claim 1, wherein the oxidant comprises an oxygen-containing atmosphere;

the oxygen partial pressure of the oxygen-containing atmosphere is 0.1-5 MPa;

preferably, the oxygen-containing atmosphere is selected from oxygen or air.

3. The method according to claim 1, wherein the molar ratio of the nitrogen source to the 2, 5-diformylfuran is 1 to 9: 1;

wherein the number of moles of the nitrogen source is based on the number of moles of the nitrogen source itself.

4. The method according to claim 1, wherein the nitrogen source is at least one selected from ammonium salts;

preferably, the ammonium salt is selected from at least one of ammonium formate, ammonium acetate, ammonium oxalate, ammonium carbonate, ammonium bicarbonate, ammonium phosphate.

5. The preparation method according to claim 1, wherein the reaction temperature is 30-120 ℃;

the reaction time is 0.5-48 h.

6. The preparation method according to claim 1, wherein the amount of the catalyst is 5 to 20 mol% of 2, 5-diformylfuran;

wherein the moles of the catalyst are based on the moles of the metal oxide.

7. The method according to claim 1, wherein the organic compound comprises at least one of acetylacetone, 3-methylacetoacetone, 1,1, 1-trifluoroacetylacetone, hexafluoroacetylacetone, N-dimethylcyclohexylamine, N-methylpiperidine, N-methyltetrahydropyrrole, and proline.

8. The production method according to claim 1, wherein the metal oxide includes at least one of an oxide of manganese, an oxide of cobalt, and an oxide of nickel;

preferably, the manganese oxide comprises amorphous manganese dioxide, alpha-MnO₂、β-MnO₂、γ-MnO₂、-MnO₂At least one of (1).

9. The method according to claim 1, wherein the organic compound is present in a molar amount of 0.5 to 5% based on the molar amount of 2, 5-diformylfuran.

10. The method of claim 1, wherein the mixture further comprises a solvent;

the solvent comprises any one of acetonitrile, dioxane, tertiary butanol, tertiary amyl alcohol, toluene and p-xylene.