A method for preparing an amine compound from a photocatalytic biomass-derived aldehyde compound

Abstract

This invention discloses a method for preparing amine compounds from biomass-derived aldehydes via photocatalysis, belonging to the field of photocatalytic organic synthesis technology. This method requires no additional hydrogen-donating reagent for amine compound preparation. Under light irradiation, through the synergistic effect of a photocatalyst and a metal co-catalyst, amine compounds are synthesized from ammonia via the reaction of biomass-derived aldehydes without the need for additional organic hydrogen-donating reagents. This method can be carried out at room temperature and pressure, has high yield, is environmentally friendly, and is suitable for industrial production.

Description

Technical Field

[0001] This invention belongs to the field of photocatalytic organic synthesis technology, specifically relating to a method for preparing amine compounds by photocatalysis using ammonia water and biomass-derived aldehyde compounds without additional hydrogen-donating reagents. Background Technology

[0002] Photocatalytic organic synthesis utilizes photogenerated electrons and holes to catalyze redox reactions. Using light as an energy source, it achieves a safe, green, efficient, and environmentally friendly new type of organic synthesis. Due to its low energy consumption, mild reaction conditions, and low pollution, it has value in many fields such as industrial production and is receiving increasing attention in the field of organic synthesis.

[0003] Amines are a core category of nitrogen-containing organic compounds, serving as key raw materials for fine chemical intermediates and organic synthesis catalysts, as well as core structural units for natural alkaloids and synthetic drugs. Biomass is the largest renewable carbon resource, and the preparation of amines from renewable biomass represents a promising high-value-added synthetic route for nitrogen-containing compounds, potentially replacing traditional fossil fuels. However, the reductive amination of biomass-derived aldehydes typically requires high temperature and / or high pressure conditions. Therefore, developing advanced catalysts or novel catalytic routes with high activity and selectivity for amine preparation is of great significance. Currently, photocatalytic synthesis of amines often uses organic nitrogen-containing precursors (such as cyanides, amines, and amides) as nitrogen sources, which presents problems such as high cost, high toxicity, and environmental risks. Furthermore, the use of additional organic hydrogen donors, such as organic alcohols, necessitates the separate separation of their oxidation products, leading to low reaction efficiency and complex processes. Liu et al. reported a Cu / TiO2 photocatalytic system using polyols and piperidine as substrates to prepare ethanolamines and ethylenediamines. However, this method uses ultraviolet light and a toxic nitrogen source, which is not conducive to large-scale production (Liu M., Li H., Zhang J., et al. Photocatalytic Production of Ethanolamines and Ethylenediamines from Bio-Polyols over a Cu / TiO2 Catalyst [J]. Angewandte Chemie International Edition, 2024, 63,e202315795.). Xue et al. used Ru(TiO2) as a photocatalyst, ammonia as a nitrogen source, and ethanol as a solvent to achieve the reduction and amination of furfural to furfurylamine. However, the use of noble metal photocatalysts and alcohol-based hydrogen donors is costly, and product separation is difficult (Xue Z., Wu S., Fu Y., et al. Efficient Light-driven Reductive Amination of Furfural to Furfurylamine over Ruthenium-cluster Catalyst [J]. Journal of Energy Chemistry. 2023, 76, 239-248.). Patent CN113999131A discloses a method for preparing amide derivatives by using a nickel catalyst to promote the direct amination of alkyl CH bonds under visible light conditions, with the substituted oxazolinone as the amination reagent. Patent CN119263997A discloses a method for synthesizing amine compounds under visible light induction using an iridium complex, a nickel catalyst, and N,N-diethylaminoethanol as the nitrogen source.However, the above methods have problems such as expensive catalysts and reliance on toxic organic nitrogen sources, which limit their further large-scale application.

[0004] Therefore, research into new, efficient, green, and economical methods for synthesizing amine compounds is of great value. Using inexpensive and readily available photocatalysts and ammonia, without the need for additional hydrogen donors, this method has broad applicability and is suitable for industrial production. Summary of the Invention

[0005] To address the shortcomings of existing amine compound synthesis technologies, this invention provides a method for photocatalytic synthesis of amine compounds.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A method for preparing amine compounds from biomass-derived aldehydes via photocatalysis involves mixing a photocatalyst, a metal co-catalyst, a biomass-derived aldehyde compound, ammonia, and a solvent to obtain a mixed solution, which is then ultrasonically dispersed and stirred under light and inert gas conditions to obtain an amine compound as shown in Formula II.

[0008] The general structural formula of the biomass-derived aldehyde compounds is shown in Formula I:

[0009] ;

[0010] Wherein, R is a furan ring or a benzene ring, and R' is one, two, three, four, or five substituents attached to the furan ring or benzene ring, each of which is independently a hydrogen element, a halogen, or a C1-C ion. 10 Alkyl, alkenyl, or ynyl, C6-C 20 Any one of aryl, -OR, -OCF3, -NHR, -C(=O)OR, -NHC(=O)R and -C(=O)R.

[0011] Furthermore, the photocatalyst is a photocatalyst composed of one or any two of the following: metal oxide semiconductor, metal sulfide / selenide semiconductor, metal nitrogen / oxygen compound semiconductor, perovskite semiconductor (ABO3), and carbon / nitrogen-based polymer semiconductor material; wherein the bandwidth range of the semiconductor material is 1-4 electron volts (eV).

[0012] Furthermore, the metal oxide semiconductor includes oxides of Ti, Zn, Zr, W, V, Cu, Fe, Ce, Ta, In, or Nb;

[0013] The metal sulfide / selenide semiconductor includes sulfur / selenium-containing compounds of Cd, Zn, Cu, W, or Bi;

[0014] The metal nitrogen / oxide semiconductor includes nitrogen-containing / oxygen compounds of Ti, Ga, Ge or Ta;

[0015] The perovskite semiconductor includes Pb, Sn, and Cl. - ,Br - I - Perovskite semiconductors;

[0016] The carbon / nitrogen-based polymer semiconductor material includes polythiophene, polycarbazole, covalent metal-organic frameworks, and graphitic carbon nitride.

[0017] Furthermore, the metal co-catalyst includes one or more of Pt, Au, Ag, Pd, Ir, Ru, Ni, and NiO.

[0018] Furthermore, the ammonia solution is a commercially available ammonia solution with a mass fraction of 25% to 28%.

[0019] Further, the solvent is one or a mixture of water, dimethyl sulfoxide, acetonitrile, N,N-dimethylformamide or 1,4-dioxane.

[0020] Furthermore, the mass ratio of the photocatalyst to the metal cocatalyst is 1:100; the concentration of the biomass-derived aldehyde compound in the mixed solution is 0~2 mmol / L, and the concentration of the photocatalyst is 5 mg / mL; the molar ratio of the biomass-derived aldehyde compound to ammonia is 1:10~800.

[0021] Furthermore, the illumination is direct sunlight or artificial light source simulating sunlight;

[0022] Furthermore, the artificial light source includes LEDs, Xe lamps, fluorescent lamps, lasers, and Hg lamps;

[0023] Furthermore, the light intensity is determined by the light source power being 0.01~50 W / cm². 2 It is achieved with white or blue LED lights.

[0024] Furthermore, the light intensity is determined by a light source power of 30 W / cm². 2 It is achieved with white or blue LED lights.

[0025] Furthermore, the inert gas is He, Ar, or N2.

[0026] Furthermore, the reaction temperature was room temperature (25℃), and the reaction time was 2~5 hours.

[0027] Compared with the prior art, the present invention has the following advantages:

[0028] This invention enables the reaction of biomass-derived aldehydes with ammonia to produce amines through the action of photocatalysts and metal co-catalysts. No additional hydrogen-donating reagents are required, resulting in high yields and conversion rates. The photocatalyst is also low in cost, making it advantageous to stably and efficiently utilize this reaction system in industrial organic synthesis to unlock its high economic value. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the reaction process of the present invention; Figure 2 (a) Liquid chromatogram of the product; (b) Mass spectrum of the product and mass spectrum from the National Institute of Standards and Technology (NIST). Detailed Implementation

[0031] To gain a deeper understanding of this invention, we will provide a comprehensive and detailed description. However, this invention has various implementations and is not limited to the specific examples listed herein. These examples are presented to enhance a full understanding of the disclosure of this invention.

[0032] Example 1

[0033] This embodiment provides a method for preparing amine compounds using photocatalysis from ammonia and biomass-derived aldehydes without additional hydrogen-donating reagents, comprising the following steps:

[0034] 20 mg of 1 wt% copper / cadmium sulfide photocatalyst and 100 μmol of furfural ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 3 h under simulated sunlight LED light irradiation and nitrogen protection to obtain furfurylamine. According to liquid chromatography analysis, the furfural conversion rate was 92% and the furfural yield was 83%.

[0035] Example 2

[0036] 20 mg of 1 wt% copper / cadmium sulfide photocatalyst and 100 μmol of 5-methylfurfural ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80W) for 10 min. The dispersed suspension was then stirred at room temperature for 3 h under simulated sunlight LED light irradiation and nitrogen protection to obtain 5-methylfurfural ( ). Analysis using liquid chromatography showed that the conversion rate of 5-methylfurfural was 85% and the yield of 5-methylfurfural was 87%.

[0037] Example 3

[0038] 20 mg of 1 wt% copper / cadmium sulfide photocatalyst and 100 μmol of 5-ethyl-2-furfural ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 3 h under simulated sunlight LED light and nitrogen protection to obtain (5-ethylfuran-2-yl)methylamine. Analysis using liquid chromatography showed that the conversion rate of 5-ethyl-2-furfural was 90%, and the yield of (5-ethylfuran-2-yl)methylamine was 85%.

[0039] Example 4

[0040] 20 mg of 1 wt% copper / cadmium sulfide photocatalyst and 100 μmol of p-methylbenzaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80W) for 10 min. The dispersed suspension was then stirred at room temperature for 3 h under simulated sunlight LED light and nitrogen protection to obtain benzylamine. The conversion rate of p-methylbenzaldehyde was 98% and the yield of benzylamine was 88% as determined by liquid chromatography.

[0041] Example 5

[0042] 20 mg of 1 wt% copper / cadmium sulfide photocatalyst and 100 μmol of p-cyanobenzaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 3 h under simulated sunlight LED light irradiation and nitrogen protection to obtain p-cyanophenylbenzylamine. The conversion rate of p-cyanobenzaldehyde was 99% and the yield of p-cyanobenzylamine was 81% as determined by liquid chromatography.

[0043] Example 6

[0044] 20 mg of 1 wt% copper / cadmium sulfide photocatalyst and 100 μmol of p-hydroxybenzaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 3 h under simulated sunlight LED light and nitrogen protection to obtain p-hydroxybenzylamine. The conversion rate of p-hydroxybenzaldehyde was 91% and the yield of p-hydroxybenzylamine was 90% as determined by liquid chromatography.

[0045] Example 7

[0046] 20 mg of 1 wt% copper / cadmium sulfide photocatalyst and 100 μmol of p-methoxybenzaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 3 h under simulated sunlight LED light and nitrogen protection to obtain p-methoxybenzylamine. The conversion rate of p-methoxybenzaldehyde was 99% and the yield of p-methoxybenzylamine was 90% as determined by liquid chromatography.

[0047] Example 8

[0048] 20 mg of 1 wt% copper / cadmium sulfide photocatalyst and 100 μmol of vanillin ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 3 h under simulated sunlight LED light and nitrogen protection to obtain 4-(aminomethyl)-2-methoxyphenol. Analysis using liquid chromatography showed that vanillin conversion was 99% and 4-(aminomethyl)-2-methoxyphenol yield was 94%.

[0049] Example 9

[0050] 20 mg of 1 wt% copper / cadmium sulfide photocatalyst and 100 μmol of 2-naphthaldehyde ( 1-(2-naphthyl)methylamine was obtained by mixing 3 mol of ammonia water with 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 and then ultrasonically dispersed (80W) for 10 min. The dispersed suspension was then stirred at room temperature for 3 h under simulated sunlight LED light and nitrogen protection to obtain 1-(2-naphthyl)methylamine. Analysis using liquid chromatography showed that the conversion rate of 2-naphthaldehyde was 99%, and the yield of 1-(2-naphthyl)methylamine was 94%.

[0051] Example 10

[0052] This embodiment provides a method for preparing amine compounds from ammonia and biomass-derived aldehydes under ambient temperature, pressure, and an inert atmosphere without the need for high-pressure hydrogen or additional organic hydrogen-donating reagents. The method includes the following steps:

[0053] 10 mg of 1wt% copper / cadmium sulfide and 2 M of furfural ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 3 h under nitrogen protection to obtain furfurylamine. According to liquid chromatography analysis, the furfural conversion rate was 92% and the furfural yield was 83%.

[0054] Example 11

[0055] 10 mg of 1wt% copper / cadmium sulfide and 2 M of 5-methylfurfural ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 3 h under nitrogen protection to obtain 5-methylfurfural ( ). Analysis using liquid chromatography showed that the conversion rate of 5-methylfurfural was 85% and the yield of 5-methylfurfural was 87%.

[0056] Example 12

[0057] 10 mg of 1wt% copper / cadmium sulfide and 2 M of 5-ethyl-2-furfural ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 3 h under nitrogen protection to obtain (5-ethylfuran-2-yl)methylamine. Analysis using liquid chromatography showed that the conversion rate of 5-ethyl-2-furfural was 90%, and the yield of (5-ethylfuran-2-yl)methylamine was 85%.

[0058] Example 13

[0059] 10 mg of 1wt% iron / graphite phase carbon nitride and 2 M of 5-iodo-2-furanaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of acetonitrile:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 4 h under nitrogen protection to obtain (5-iodofuran-2-yl)methylamine. Analysis using liquid chromatography showed that the conversion rate of 5-iodo-2-furan carbaldehyde was 98%, and the yield of (5-iodofuran-2-yl)methylamine was 87%.

[0060] Example 14

[0061] 10 mg of 1wt% iron / graphite phase carbon nitride and 2 M of 4,5-dimethyl-2-furfural were added. 3 mol of ammonia water and 2 mL of a mixed solvent of acetonitrile:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 4 h under nitrogen protection to obtain (4,5-dimethylfuran-2-yl)methylamine. Analysis using liquid chromatography showed that the conversion rate of 4,5-dimethyl-2-furfural was 98%, and the yield of (4,5-dimethylfuran-2-yl)methylamine was 80%.

[0062] Example 15

[0063] 10 mg of 1wt% iron / graphite phase carbon nitride and 2 M of 5-hydroxymethylfurfural ( 3 mol of ammonia water and 2 mL of a mixed solvent of acetonitrile:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 4 h under nitrogen protection to obtain 5-(aminomethyl)furan-2-yl]methanol. Analysis using liquid chromatography showed that the conversion rate of 5-hydroxymethylfurfural was 93%, and the yield of 5-(aminomethyl)furan-2-yl]methanol was 80%.

[0064] Example 16

[0065] 10 mg of 1wt% iron / graphite phase carbon nitride and 2 M of 2,5-furandialdehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of acetonitrile:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 4 h under nitrogen protection to obtain 2,5-furandimethylamine. Analysis using liquid chromatography showed that the conversion rate of 2,5-furandicarboxaldehyde was 90%, and the yield of 2,5-furandimethylamine was 83%.

[0066] Example 17

[0067] 10 mg of 1wt% iron / graphite phase carbon nitride and 1.5 M benzaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of acetonitrile:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 4 h under argon protection to obtain benzylamine. The conversion rate of benzaldehyde was 90% and the yield of benzylamine was 90% as determined by liquid chromatography.

[0068] Example 18

[0069] 10 mg of 1 wt% Fe-MOF and 1.5 M of p-methylbenzaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 4 h under argon protection to obtain p-methylbenzylamine. The conversion rate of p-methylbenzaldehyde was 98% and the yield of p-methylbenzylamine was 88% as determined by liquid chromatography.

[0070] Example 19

[0071] 10 mg of 1wt% Fe-MOF and 1.5 M of p-methoxybenzamide were added. 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 4 h under argon protection to obtain p-methoxybenzylamine. The conversion rate of p-methoxybenzaldehyde was 99% and the yield of p-methoxybenzylamine was 90% as determined by liquid chromatography.

[0072] Example 20

[0073] 10 mg of 1wt% Fe-MOF and 1.5 M of p-cyanobenzaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 4 h under argon protection to obtain p-cyanophenylbenzylamine. The conversion rate of p-cyanobenzaldehyde was 99% and the yield of p-cyanobenzylamine was 81% as determined by liquid chromatography.

[0074] Example 21

[0075] 10 mg of 1 wt% Fe-MOF and 1.5 M of p-hydroxybenzaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 4 h under argon protection to obtain p-hydroxybenzylamine. The conversion rate of p-hydroxybenzaldehyde was 91% and the yield of p-hydroxybenzylamine was 90% as determined by liquid chromatography.

[0076] Example 22

[0077] 10 mg of 1wt% platinum / graphite phase carbon nitride and 1.5 M of p-bromobenzaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of acetonitrile:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 4 h under argon protection to obtain p-benzyl bromide. The conversion rate of p-bromobenzaldehyde was 89% and the yield of p-bromobenzylamine was 90% as determined by liquid chromatography.

[0078] Example 23

[0079] 10 mg of 1wt% platinum / graphite phase carbon nitride, 1.5 M of p-fluorobenzaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of acetonitrile:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 4 h under argon protection to obtain p-fluorobenzylamine (…). The conversion rate of p-fluorobenzaldehyde was 89% and the yield of p-fluorobenzylamine was 94% as determined by liquid chromatography.

[0080] Example 24

[0081] Add 10 mg of 1wt% copper / titanium dioxide and 0.5 M of vanillin ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 4 h under argon protection to obtain 4-(aminomethyl)-2-methoxyphenol. Analysis using liquid chromatography showed that vanillin conversion was 99% and 4-(aminomethyl)-2-methoxyphenol yield was 94%.

[0082] Example 25

[0083] 10 mg of 1wt% copper / titanium dioxide and 0.5 M of 2-naphthaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of 1,4-dioxane:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 5 h under argon protection to obtain 1-(2-naphthyl)methylamine. Analysis using liquid chromatography showed that the conversion rate of 2-naphthaldehyde was 99%, and the yield of 1-(2-naphthyl)methylamine was 94%.

[0084] Example 26

[0085] 10 mg of 1wt% copper / titanium dioxide and 0.5 M of quinoline-6-carboxaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of acetonitrile:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 5 h under argon protection to obtain 6-aminomethylquinoline (… Analysis using liquid chromatography showed that the conversion rate of quinoline-6-formaldehyde was 99%, and the yield of 6-aminomethylquinoline was 84%.

[0086] Example 27

[0087] 10 mg of 1wt% palladium / titanium dioxide and 0.5 M of cyclohexylformaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of acetonitrile:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 5 h under argon protection to obtain cyclohexylmethylamine. The conversion rate of cyclohexylformaldehyde was 89% and the yield of cyclohexylmethylamine was 84% ​​as determined by liquid chromatography.

[0088] Example 28

[0089] 10 mg of 1wt% palladium / titanium dioxide and 0.5 M of cyclopentylformaldehyde ( 3 mol of ammonia water and 2 mL of a mixed solvent of acetonitrile:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 5 h under argon protection to obtain cyclopentylmethylamine. The conversion rate of cyclopentylformaldehyde was 99% and the yield of cyclopentylmethylamine was 83% as determined by liquid chromatography.

[0090] Example 29

[0091] 10 mg of 1wt% palladium / titanium dioxide and 0.5 M μmol of n-hexanal ( 3 mol of ammonia water and 2 mL of a mixed solvent of acetonitrile:water (v / v) = 3:7 were mixed evenly and then ultrasonically dispersed (electric power 80 W) for 10 min. The dispersed suspension was then stirred at room temperature for 5 h under argon protection to obtain n-hexylamine. Analysis using liquid chromatography showed that the conversion rate of hexanal was 88% and the yield of hexylamine was 85%.

[0092] Comparative Example 1

[0093] This example is basically the same as that in Example 1, except that no photocatalyst was used and the result of the final step (c) was that no amine compound could be obtained.

[0094] Comparative Example 2

[0095] This example is basically the same as that in Example 1, except that no light was applied and the result of the final step (c) was that no amine compound could be obtained.

[0096] Contents not described in detail in this specification are prior art known to those skilled in the art. Although illustrative specific embodiments of the invention have been described above to facilitate understanding by those skilled in the art, it should be understood that the invention is not limited to the scope of the specific embodiments. Various modifications are readily apparent to those skilled in the art as long as they fall within the spirit and scope of the invention as defined and determined by the appended claims, and all inventions utilizing the concept of this invention are protected.

Claims

1. A method for preparing amine compounds from biomass-derived aldehydes via photocatalysis, characterized in that, A mixed solution was obtained by mixing a photocatalyst, a metal co-catalyst, a biomass-derived aldehyde compound, ammonia, and a solvent. After ultrasonic dispersion, the solution was stirred and reacted under light and inert gas conditions to obtain an amine compound as shown in Formula II. The general structural formula of the biomass-derived aldehyde compounds is shown in Formula I: ； wherein R is a furan ring or a benzene ring, R' is one, two, three, four or five substituents attached to the furan ring or the benzene ring, each of said substituents being independently of the others hydrogen, halogen, C1-C 10 alkyl or alkenyl or alkynyl, C6-C 20 aryl, -OR, -OCF3, -NHR, -C(=O)OR, -NHC(=O)R and -C(=O)R.

2. The method for preparing amine compounds from photocatalytically derived biomass aldehydes according to claim 1, characterized in that, The photocatalyst is a photocatalyst composed of one or any two of the following: metal oxide semiconductor, metal sulfide / selenide semiconductor, metal nitrogen / oxygen compound semiconductor, perovskite semiconductor, and carbon / nitrogen-based polymer semiconductor; wherein the bandwidth range of the semiconductor material is 1-4 electron volts (eV).

3. The method for preparing amine compounds from photocatalytically derived biomass aldehydes according to claim 2, characterized in that, The metal oxide semiconductor includes oxides containing Ti, Zn, Zr, W, V, Cu, Fe, Ce, Ta, In, or Nb; The metal sulfide / selenide semiconductor includes sulfur / selenium-containing compounds of Cd, Zn, Cu, W, or Bi; The metal nitride / oxide semiconductor includes nitrogen-containing / oxygen compounds of Ti, Ga, Ge, or Ta; The perovskite semiconductor includes Pb, Sn, and Cl. - ,Br - I - Perovskite semiconductors; The carbon / nitrogen-based polymer semiconductor material includes polythiophene, polycarbazole, covalent metal-organic frameworks, and graphitic carbon nitride.

4. The method for preparing amine compounds from photocatalytically derived biomass aldehydes according to claim 1, characterized in that, The metal co-catalyst includes one or more of Pt, Au, Ag, Pd, Ir, Ru, Ni, and NiO.

5. The method for preparing amine compounds from photocatalytically derived biomass aldehydes according to claim 1, characterized in that, The ammonia solution is a commercially available ammonia solution with a mass fraction of 25% to 28%.

6. The method for preparing amine compounds from photocatalytically derived biomass aldehydes according to claim 1, characterized in that, The solvent is one or a mixture of water, dimethyl sulfoxide, acetonitrile, N,N-dimethylformamide or 1,4-dioxane.

7. The method for preparing amine compounds from photocatalytically derived biomass aldehydes according to claim 1, characterized in that, The mass ratio of the photocatalyst to the metal cocatalyst is 1:100; The concentration of biomass-derived aldehydes in the mixed solution is 0-2 mmol / L, and the concentration of the photocatalyst is 5 mg / mL. The molar ratio of biomass-derived aldehydes to ammonia is 1:10~800.

8. The method for preparing amine compounds from photocatalytically derived biomass aldehydes according to claim 1, characterized in that, The illumination is direct sunlight or artificial light source that simulates sunlight; The artificial light sources include LEDs, Xe lamps, fluorescent lamps, lasers, and Hg lamps; The light intensity is determined by a light source power of 30 W / cm². 2 It can be achieved with white or blue LED lights.

9. The method for preparing amine compounds from photocatalytically derived biomass aldehydes according to claim 1, characterized in that, The inert gas is He, Ar, or N2.

10. The method for preparing amine compounds from photocatalytically derived biomass aldehydes according to claim 1, characterized in that, The reaction temperature is room temperature, and the reaction time is 2-5 hours.

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