A method for directly catalyzing camphor compounds to prepare borneol amine compounds

Abstract

The present invention provides a method for directly catalyzing camphor to prepare bornylamine, relating to the technical field of organic synthesis. The method provided by the present invention involves reacting a camphoraldehyde compound with a Ru / Zr(OH)4 catalyst in an ammonia solvent environment, a hydrogen-containing atmosphere, and 50°C to 300°C to produce bornylamine. The method provided by the present invention utilizes camphoraldehyde compounds as reaction substrates, enabling the direct and efficient synthesis of bornylamine. The reaction is green, efficient, has high atom utilization, and is pollution-free.

Description

Technical Field

[0001] The present invention relates to the technical field of organic synthesis, in particular to a method for preparing borneol amine compounds by directly catalyzing camphor compounds. Background Art

[0002] Camphor groups are important building blocks of chiral ligands used in asymmetric synthesis catalysis and can also serve as auxiliary groups in asymmetric synthesis. Due to steric hindrance, camphor-based molecules have limited application in asymmetric catalysis and synthesis. Camphor is a readily available starting molecule for the preparation of diverse biologically active compounds. For example, bornylamine can serve as an organic synthesis intermediate, surfactant, drug carrier, ligand, building block for local anesthetics, and a precursor for β-adrenergic receptor agonists and inhibitors. In the pharmaceutical field, bornylamine is used for central nervous system regulation, cardiovascular protection, anti-inflammatory and analgesic effects, and as a drug carrier. In the chemical industry, it can serve as an organic synthesis intermediate and in the preparation of surfactants. However, the reductive amination of camphor and anisone remains a challenge. The standard reductive amination method involves two steps: preparation of an imine or Schiff base in the presence of a strong Lewis acid, followed by reduction with a conventional reducing agent. In most cases, the first stage of this process requires relatively harsh conditions. Currently, reported methods for the direct reductive amination of camphor or anisone are limited and complex.

[0003] Therefore, it is urgent to find a new solution to improve the above problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for directly catalyzing camphor compounds to prepare borneol amine compounds. Camphor aldehyde compounds are used as reaction substrates. Camphor aldehyde compounds react under the catalysis of Ru / Zr(OH)4 catalyst to directly generate borneol amine compounds. The reaction is green and efficient, has high atomic utilization rate, and is pollution-free.

[0005] The technical solutions of the present invention are as follows:

[0006] A method for directly catalyzing camphor compounds to prepare borneol amine compounds comprises: in an ammonia solvent environment, a hydrogen-containing atmosphere, and a temperature of 50° C. to 300° C., reacting camphor aldehyde compounds with a Ru / Zr(OH)4 catalyst to generate corresponding borneol amine compounds;

[0007] ;

[0008] Among them, R1, R2, and R3 are independently an alkyl group, an aromatic ring, or a furan ring.

[0009] Optionally, the ammonia solvent environment includes 1%-50% ammonia.

[0010] Optionally, the hydrogen concentration in the hydrogen-containing atmosphere is 10%-100%.

[0011] Optionally, the pressure of the hydrogen-containing atmosphere is 1 MPa-5 MPa.

[0012] Optionally, the camphoraldehyde compound is reacted under the catalysis of Ru / Zr(OH)4 catalyst for 1h-30h.

[0013] Optionally, the reaction temperature of the camphoraldehyde compound under the catalysis of Ru / Zr(OH)4 catalyst is 50°C-300°C.

[0014] Optionally, the particle size of the Ru / Zr(OH)4 catalyst is 1 nm-100 nm.

[0015] Optionally, the concentration of the ammonia water is 1%-50%.

[0016] Optionally, the Ru / Zr(OH)4 catalyst carrier is zirconium hydroxide and the active ruthenium loaded thereon, and the loading amount of the active ruthenium on the catalytic carrier (carrier zirconium hydroxide) is 0.1 wt%-50 wt%.

[0017] Optionally, the Ru / Zr(OH)4 catalyst preparation method includes dissolving a zirconium salt and a ruthenium salt in an ammonia solvent environment, adding a strong base and the zirconium salt to in situ generate a supported zirconium hydroxide, reducing the ruthenium salt to obtain active ruthenium (ruthenium metal), and filtering and drying to obtain the Ru / Zr(OH)4 catalyst. In some embodiments, ZrCl4 and RuCl3•xH2O, serving as catalyst precursors, are first mixed, followed by the addition of sodium hydroxide to in situ synthesize Zr(OH)4, followed by the addition of NaBH4, followed by filtration and drying to obtain the Ru / Zr(OH)4 catalyst.

[0018] Optionally, the specific surface area of ​​the catalytic carrier is 10m 2 / g-500m 2 / g.

[0019] Optionally, the ruthenium salt includes ruthenium chloride, ruthenium nitrate or ruthenium sulfate.

[0020] Optionally, the preparation method of the Ru / Zr(OH)4 catalyst comprises the following steps: dissolving a zirconium salt and a ruthenium salt in a solvent solution by stirring to obtain a mixed suspension, stirring, adding a strong base and the zirconium salt to in situ generate a supported zirconium hydroxide, adding sodium borohydride to reduce the ruthenium salt to obtain active ruthenium, and filtering, drying, and grinding to obtain the Ru / Zr(OH)4 catalyst. In some embodiments, ZrCl4 and RuCl3·xH2O (37-40 wt%) are first dissolved in N,N-dimethylformamide to obtain a mixed suspension, which is then stirred at room temperature for 10 hours. A 1 M aqueous NaOH solution is then added to adjust the pH to 7 and stirred for 1 hour. After a green precipitate forms, NaBH4 (NaBH4:Ru, 5:1 mol / mol) is added, and the mixture is stirred for 1 hour. Finally, the precipitate is isolated and washed three times with deionized water. The precipitate is dried at 100°C overnight to obtain dark green crystals, which are then ground to obtain Ru / Zr(OH)4. Optionally, the precipitate is dried at 80-120° C. Optionally, the precipitate is dried for 8-12 hours. Optionally, the mixed suspension of ZrCl 4 and RuCl 3 • xH 2 O is stirred for 8-24 hours.

[0021] Alternatively, the catalytic support is dispersed in the mixed suspension under mechanical mixing, which includes stirring, shaking or ultrasound.

[0022] Alternatively, the zirconium salt and the ruthenium salt are dissolved in a solvent and stirred at room temperature for 8 h to 24 h.

[0023] Optionally, a strong alkaline solution is added to adjust the pH to 7 and stirred for 0.5 h to 4 h to prepare zirconium hydroxide.

[0024] Optionally, add NaBH4 and stir for 0.5h-4h.

[0025] Optionally, the amount of NaBH4 added is 5-10 times the molar amount of the ruthenium salt.

[0026] Optionally, the camphoraldehyde compound includes a camphor-based compound or anisone, and the camphor-based compound includes camphor.

[0027] Optionally, the strong base is one of sodium hydroxide, potassium hydroxide, calcium hydroxide, and barium hydroxide; and the zirconium salt includes zirconium acetate, zirconium carbonate, zirconium chloride, zirconium nitrate, or zirconium sulfate.

[0028] Optionally, the mass ratio of the camphoraldehyde compound to the Ru / Zr(OH)4 catalyst is (0.01-1000):1.

[0029] Optionally, the mass concentration of the camphoraldehyde compound in the solvent environment is 0.001%-50%.

[0030] Beneficial effects of the present invention:

[0031] (1) The preparation method provided by the present invention does not require the addition of additives, saves energy, and generates H2O as a by-product, which is green, efficient, and environmentally friendly.

[0032] (2) The preparation method provided by the present invention has high substrate universality and is suitable for reactions using one or more mixtures of camphor-based, aromatic aldehydes, furan-based aldehydes and alkyl aldehydes as substrates. The catalyst has the advantages of a wide substrate range, good stability, a simple catalytic process and easy separation, and has potential application prospects in the chemical industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The chemical reaction formula for preparing bornylamine from camphor provided by the present invention;

[0034] Figure 2 Schematic diagram of the technical route for preparing bornylamine from camphor;

[0035] Figure 3 Schematic diagram of the reaction mechanism of camphor converted to bornylamine on the catalyst surface;

[0036] Figure 4 Flowchart of the preparation method of Ru / Zr(OH)4 catalyst in some embodiments of the present invention;

[0037] Figure 5 Diagram of the method for preparing bornylamine from camphor. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be the common meanings understood by people with ordinary skills in the field to which the present invention belongs.

[0039] See also Figure 1 The present invention provides a method for directly catalyzing camphor compounds to prepare borneol amine compounds, comprising: in an ammonia solvent environment, a hydrogen-containing atmosphere, and a temperature of 50°C to 300°C, camphor aldehyde compounds react under the catalysis of a Ru / Zr(OH)4 catalyst to generate corresponding borneol amine compounds;

[0040] ;

[0041] Wherein, R1, R2, and R3 are independently an alkyl group, an aromatic ring, or a furan ring.

[0042] In fact, see Figure 2 In the reaction process, camphoraldehyde compounds first react with ammonia water to reduce and aminize to form imine, and the imine is further hydrogenated in a hydrogen-containing atmosphere to form bornylamine. Figure 3 From the reaction path of camphoraldehyde compounds to borneolamine, it can be seen that camphoraldehyde compounds first react with ammonia to obtain imine, and hydrogen is activated to H at the catalyst interface. + and H - , adsorbed on the basic site and metal respectively, and then the imine is adsorbed by the catalyst and catalytically hydrogenated to obtain bornylamine.

[0043] In some embodiments, the solvent environment used is an ammonia solvent environment, and the ammonia solvent environment includes 1%-50% ammonia. In fact, when selecting the solvent environment, organic solvents and ammonia gas can be used. It is necessary that the organic solvent does not chemically react with the camphoraldehyde compound. In the present invention, N,N-dimethylformamide solution is selected as the organic solvent. In addition, by carrying out the preparation reaction in a solvent environment, it is beneficial for the camphoraldehyde compound to fully contact with the Ru / Zr(OH)4 catalyst.

[0044] In some embodiments, the hydrogen concentration in the hydrogen-containing atmosphere during the reaction is 10%-100%. In fact, when camphoraldehyde compounds are catalyzed by Ru / Zr(OH)4 catalysts to produce bornylamine, hydrogen is required to participate in the reaction, and the hydrogen content is positively correlated with the reaction rate to a certain extent. Specifically, when the hydrogen concentration in the hydrogen-containing atmosphere is less than 100%, the hydrogen-containing atmosphere may also include a non-oxidizing carrier gas, such as an inert gas such as nitrogen, argon, or helium.

[0045] In practice, since the concentration of hydrogen decreases after participating in the reaction, a certain amount of hydrogen can be added to the reaction environment as the reaction progresses to maintain a stable hydrogen concentration. In some embodiments, the pressure of the hydrogen-containing atmosphere during the reaction is 0.5 MPa-5 MPa. Maintaining this pressure environment is beneficial for promoting the forward progress of the preparation reaction.

[0046] In some embodiments, the camphoraldehyde compound is reacted under the catalysis of Ru / Zr(OH)4 catalyst for 0.1h-10h.

[0047] In some embodiments, the mass ratio of the camphoraldehyde compound to the Ru / Zr(OH)4 catalyst is (0.01-1000):1. Adjusting the ratio of reactants to catalysts facilitates sufficient contact between the camphoraldehyde compound and the catalyst in the solvent environment, thereby facilitating a reaction at the Ru-metal interface. Specifically, the mass concentration of the camphoraldehyde compound in the solvent environment is 0.001%-50%.

[0048] Specifically, the Ru / Zr(OH)4 catalyst used includes a catalytic carrier and active ruthenium loaded thereon. By using a catalytic carrier for loading, it is beneficial to increase the loading amount of active ruthenium, while providing an anchoring effect for the active ruthenium and increasing the specific surface area of ​​the metal catalyst, which is beneficial to promote contact between ruthenium and camphoraldehyde compounds.

[0049] In some embodiments, the preparation method of a Ru / Zr(OH)4 catalyst includes dissolving catalyst precursors (zirconium salt and ruthenium salt) in a solvent solution, adding a strong base to in situ generate a supported zirconium hydroxide, then adding sodium borohydride to reduce the ruthenium salt to obtain active ruthenium (ruthenium metal), and finally filtering and drying to obtain the Ru / Zr(OH)4 catalyst. In practice, in situ catalyst synthesis facilitates uniform adhesion of the ruthenium metal to the surface of the catalyst support.

[0050] In some embodiments, the catalytic carrier used includes zirconium hydroxide in different forms. In addition, the specific surface area of ​​the catalytic carrier used is 10m 2 / g-500m 2 / g. In practice, the ruthenium salt used includes ruthenium chloride, ruthenium nitrate or ruthenium sulfate.

[0051] In some embodiments, see Figure 4 , a method for preparing a Ru / Zr(OH)4 catalyst comprises the following steps:

[0052] S1. dissolving a zirconium salt and a ruthenium salt in a solvent solution and stirring at room temperature;

[0053] S2, adding a strong alkaline solution to prepare zirconium hydroxide;

[0054] S3, adding sodium borohydride to reduce the ruthenium salt to active ruthenium (ruthenium metal);

[0055] S4. Filter and dry the solution to obtain the catalyst Ru / Zr(OH)4.

[0056] In some embodiments, the addition of a strong base to in-situ synthesize the catalyst support and simultaneously reduce the metal salt in-situ facilitates uniform distribution of ruthenium metal within the catalyst support. Zirconium and ruthenium salts are dissolved in a solvent solution and stirred at room temperature for 8-24 hours. A strong base solution is then added to adjust the pH to 7 and stirred for 0.5-4 hours to prepare zirconium hydroxide. Sodium borohydride, 5-10 times the molar amount of the ruthenium salt, is then added to reduce the ruthenium salt to ruthenium metal. Furthermore, the Ru / Zr(OH)4 catalyst prepared by filtration, drying, and grinding has a particle size of 1-100 nm.

[0057] Preparation Example

[0058] This preparation example provides a method for preparing a Ru / Zr(OH)4 catalyst, comprising the following steps:

[0059] S1. Dissolve ruthenium chloride and zirconium chloride in N,N-dimethylformamide solution by stirring, and stir at 500 rpm for 12 h at room temperature to obtain a mixed suspension;

[0060] S2, adding 1 M NaOH aqueous solution to the mixed suspension to adjust the pH to 7 and stirring for 2 h to obtain Zr(OH)4;

[0061] S3, adding 5 times the molar amount of NaBH4 as that of the ruthenium salt (NaBH4: Ru, 5:1, mol / mol) to the mixed suspension and stirring the mixture for 1 h to reduce the ruthenium salt to ruthenium metal;

[0062] S4. The mixed suspension was filtered, dried at 100°C for 10 h and ground to obtain a green powdery Ru / Zr(OH)4 catalyst.

[0063] The Ru / Zr(OH)4 catalyst prepared in the preparation example was used to prepare the amines in Examples 1 to 10, and the Ru / Zr(OH)4 catalyst was expressed as aRu / catalytic support, for example, 4Ru / Zr(OH)4, which means that Zr(OH)4 was used as the catalytic support, and the content of active ruthenium on the catalytic support was 4 wt%.

[0064] At the same time, the yields of the reaction products of Examples 1 to 10 were detected, wherein the quantitative analysis was performed using an Agilent 7890A series gas chromatograph (FID detector, Agilent HP-5 chromatographic column: 30m*32um*0.25um), and the qualitative analysis was performed using a Thermoscientific TRACE 1310 gas mass spectrometer (HP-5 capillary column 30m*320μm*0.25μm).

[0065] Example 1

[0066] This Example 1 provides a method for preparing borneolamine from camphor, comprising: adding 100 mg of camphor, 10 mg of a metal catalyst (4Ru / Zr(OH)4), and 20 mL of 25% ammonia water to a 50 mL reactor, sealing the reactor, introducing hydrogen to adjust the pressure in the reactor to 2 MPa, stirring the mixture in the reactor and heating it to 180°C for 20 hours, cooling the reactor to room temperature in an ice-water bath, collecting the organic phase, and detecting the yield of borneolamine in the product, which was 95%.

[0067] Example 2

[0068] This Example 2 provides a method for preparing borneolamine from camphor, comprising: adding 200 mg of camphor, 20 mg of a metal catalyst (1Ru / Zr(OH)4), and 15 mL of 35% ammonia water to a 50 mL reactor, sealing the reactor, introducing hydrogen to adjust the pressure in the reactor to 1 MPa, stirring the mixture in the reactor and heating it to 300°C for 15 hours, cooling the reactor to room temperature in an ice-water bath, collecting the organic phase, and detecting the yield of borneolamine in the product, which was 91%.

[0069] In fact, in addition to directly catalyzing camphor to produce bornylamine, the present invention can also use other aldehyde compounds as reaction substrates. The aldehyde compounds used include any of camphor-based compounds, benzaldehyde-based compounds, furfural-based compounds, and fatty aldehyde-based compounds. The metal catalyst of the present invention directly catalyzes aldehyde compounds to produce amine compounds. The process is easy to control, has good universality, is conducive to industrial production, and can efficiently synthesize amine compounds. The reaction is green and efficient, with high atom utilization and no pollution. This technology can convert various substrates including camphor-based, aromatic and alkyl groups into corresponding amines with a yield of greater than 80%. See Examples 3-10 for details.

[0070] Example 3

[0071] This Example 3 provides a method for preparing aniline from benzaldehyde, comprising: adding 200 mg of benzaldehyde, 10 mg of a metal catalyst (10Ru / Zr(OH)4), and 10 mL of 10% aqueous ammonia to a 50 mL reactor, sealing the reactor, introducing hydrogen to adjust the pressure in the reactor to 1 MPa, stirring the mixture in the reactor and heating it to 180°C for 1 hour, cooling the reactor to room temperature in an ice-water bath, collecting the organic phase, and analyzing the product to determine a yield of aniline of 97%.

[0072] Example 4

[0073] This Example 4 provides a method for preparing p-methylaniline from p-methylbenzaldehyde, comprising: adding 300 mg of p-methylbenzaldehyde, 100 mg of a metal catalyst (20Ru / Zr(OH)4), and 20 mL of 50% aqueous ammonia to a 50 mL reactor, sealing the reactor, introducing hydrogen to adjust the pressure in the reactor to 5 MPa, stirring the mixture in the reactor and heating it to 170°C for 10 hours, cooling the reactor to room temperature in an ice-water bath, collecting the organic phase, and detecting the yield of p-methylaniline in the product. The yield was 91%.

[0074] Example 5

[0075] This Example 5 provides a method for preparing m-methylaniline from m-methylbenzaldehyde, comprising: adding 100 mg of m-methylbenzaldehyde, 1 mg of a metal catalyst (50Ru / Zr(OH)4), and 20 mL of 30% aqueous ammonia to a 50 mL reactor, sealing the reactor, introducing hydrogen to adjust the pressure in the reactor to 1 MPa, stirring the mixture in the reactor and heating it to 240°C for 9 hours, cooling the reactor to room temperature in an ice-water bath, collecting the organic phase, and detecting the yield of the product m-methylaniline, which was 92%.

[0076] Example 6

[0077] This Example 6 provides a method for preparing furfural amine from furfural, comprising: adding 100 mg of furfural, 0.1 mg of a metal catalyst (5Ru / Zr(OH)4), and 10 mL of 10% ammonia water to a 50 mL reactor, sealing the reactor, introducing hydrogen to adjust the pressure in the reactor to 5 MPa, stirring the mixture in the reactor and heating it to 150°C for 25 hours, cooling the reactor to room temperature in an ice-water bath, collecting the organic phase, and detecting the yield of furfural amine in the product, which was 92%.

[0078] Example 7

[0079] This Example 7 provides a method for preparing 5-methylfurfural from 5-methylfurfural, comprising: adding 100 mg of 5-methylfurfural, 100 mg of a metal catalyst (20Ru / Zr(OH)4), and 15 mL of 1% ammonia water to a 50 mL reactor, sealing the reactor, introducing hydrogen to adjust the pressure in the reactor to 3 MPa, stirring the mixture in the reactor and heating it to 180°C for 5 hours, cooling the reactor to room temperature in an ice-water bath, collecting the organic phase, and detecting the yield of 5-methylfurfural in the product. The yield was 81%.

[0080] Example 8

[0081] This Example 8 provides a method for preparing octylamine from octanal, comprising: adding 100 mg of octanal, 40 mg of a metal catalyst (3Ru / Zr(OH)4), and 10 mL of 10% ammonia water to a 50 mL reactor, sealing the reactor, introducing hydrogen to adjust the pressure in the reactor to 2 MPa, stirring the mixture in the reactor and heating it to 200°C for 20 hours, cooling the reactor to room temperature in an ice-water bath, collecting the organic phase, and detecting the yield of octylamine in the product, which was 89%.

[0082] Example 9

[0083] This Example 9 provides a method for preparing 1,4-butanediamine from 1,4-butanedialdehyde, comprising: adding 1 g of 1,4-butanedialdehyde, 100 mg of a metal catalyst (20Ru / Zr(OH)4), and 10 mL of 30% ammonia water to a 50 mL reactor, sealing the reactor, introducing hydrogen to adjust the pressure in the reactor to 3 MPa, stirring the mixture in the reactor and heating it to 260°C for 20 hours, cooling the reactor to room temperature in an ice-water bath, collecting the organic phase, and detecting the yield of 1,4-butanediamine in the product to be 95%.

[0084] Example 10

[0085] This Example 10 provides a method for preparing 1,6-hexanediamine from 1,6-hexanedialdehyde, comprising: adding 100 mg of 1,6-hexanedialdehyde, 50 mg of a metal catalyst (0.1Ru / Zr(OH)4), and 10 mL of 40% ammonia water to a 50 mL reactor, sealing the reactor, introducing hydrogen to adjust the pressure in the reactor to 5 MPa, stirring the mixture in the reactor and heating it to 240°C for 2 hours, cooling the reactor to room temperature in an ice-water bath, collecting the organic phase, and detecting the yield of 1,6-hexanediamine in the product, which was 98%.

[0086] The above detailed description is a specific description of one feasible embodiment of the present invention. This embodiment is not intended to limit the patent scope of the present invention. Any equivalent implementation or modification that does not depart from the present invention should be included in the scope of the technical solution of the present invention.

Claims

1. A method for directly catalyzing camphor compounds to prepare borneol amine compounds, characterized in that: include: In an ammonia solvent environment, a hydrogen-containing atmosphere, and a temperature of 50°C to 300°C, camphoraldehyde compounds react with Ru / Zr(OH)4 catalyst to generate corresponding borneol amine compounds; ； Wherein, R1, R2, and R3 are independently an alkyl group, an aromatic ring, or a furan ring; The ammonia solvent environment includes 1%-50% ammonia; and / or, the hydrogen concentration in the hydrogen-containing atmosphere is 10%-100%; and / or, the pressure of the hydrogen-containing atmosphere is 1 MPa-5 MPa; and / or, the camphoraldehyde compound is reacted under the catalysis of the Ru / Zr(OH)4 catalyst for 1 hour-30 hours; and / or, the particle size of the Ru / Zr(OH)4 catalyst is 1 nm-100 nm; The preparation method of the Ru / Zr(OH)4 catalyst includes: dissolving zirconium salt and ruthenium salt in an ammonia solvent environment, adding a strong base and zirconium salt to in situ generate a carrier zirconium hydroxide, reducing the ruthenium salt to obtain active ruthenium, and filtering and drying to obtain the Ru / Zr(OH)4 catalyst.

2. The method for preparing borneol amine compounds by direct catalysis of camphor compounds according to claim 1, characterized in that: The Ru / Zr(OH)4 catalyst includes a carrier zirconium hydroxide and active ruthenium supported thereon, and the loading amount of the active ruthenium on the carrier zirconium hydroxide is 0.1 wt%-50 wt%.

3. The method for preparing borneol amine compounds by direct catalysis of camphor compounds according to claim 1, characterized in that: The specific surface area of ​​the carrier zirconium hydroxide is 10m 2 / g-500m 2 / g; and / or, the ruthenium salt includes ruthenium chloride, ruthenium nitrate or ruthenium sulfate.

4. The method for preparing borneol amine compounds by direct catalysis of camphor compounds according to claim 1, characterized in that: The preparation method of the Ru / Zr(OH)4 catalyst includes the following steps: stirring and dissolving a zirconium salt and a ruthenium salt in a solvent, adding a strong base and the zirconium salt to in situ generate a carrier zirconium hydroxide, adding sodium borohydride to reduce the ruthenium salt to obtain active ruthenium, and filtering, drying and grinding to obtain the Ru / Zr(OH)4 catalyst.

5. The method for preparing borneol amine compounds by direct catalysis of camphor compounds according to claim 4, characterized in that: A strong base and a zirconium salt are added to in situ synthesize a supported zirconium hydroxide and then the ruthenium salt is reduced in situ; and / or, the zirconium salt and the ruthenium salt are dissolved in a solvent and stirred at room temperature for 8 hours to 24 hours; and / or, a strong base solution is added to adjust the pH to 7 and stirred for 0.5 hours to 4 hours to prepare the supported zirconium hydroxide; and / or, sodium borohydride is added in an amount 5 to 10 times the molar amount of the ruthenium salt to reduce the ruthenium salt to active ruthenium; and / or, the particle size of the Ru / Zr(OH)4 catalyst obtained by filtration, drying and grinding is 1 nm to 100 nm.

6. The method for preparing borneol amine compounds by direct catalysis of camphor compounds according to claim 4, characterized in that: The strong base is one of sodium hydroxide, potassium hydroxide, calcium hydroxide, and barium hydroxide; the zirconium salt includes zirconium acetate, zirconium carbonate, zirconium chloride, zirconium nitrate, or zirconium sulfate.

7. The method for preparing borneol amine compounds by direct catalysis of camphor compounds according to claim 1, characterized in that: The mass ratio of the camphoraldehyde compound to the Ru / Zr(OH)4 catalyst is (0.01-1000):1; and / or the mass concentration of the camphoraldehyde compound in the ammonia solvent environment is 0.001%-50%.

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