Metal catalyst as well as preparation method and application thereof

Abstract

The invention discloses a metal catalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: carrying out a first reaction on a mixed reaction system at least containing a metal salt, a cocatalyst and an organic solvent, and then adding an alkaline substance for a second reaction to prepare the metal catalyst. The catalyst precursor adopted in the invention is a non-noble metal salt, the reaction condition is mild, the operation is simple, and the prepared metal catalyst has a wide substrate application range and good functional group tolerance, and has low requirements on equipment.

Description

Technical Field

[0001] The present invention belongs to the field of catalysis and organic synthesis, and relates to a metal catalyst and a preparation method and application thereof, and in particular to a metal catalyst and a preparation method thereof, and application of the metal catalyst in catalyzing the hydrogenation reduction of aromatic compounds and / or heteroaromatic compounds to prepare cycloalkane compounds and / or saturated heterocyclic compounds. Background Art

[0002] Organic compounds containing cycloalkyl or heterocyclic structures are important raw materials for the synthesis of drugs, pesticides and materials, such as cyclohexanol, cyclohexane, 1,4-cyclohexanedimethanol, piperazine, etc. Catalytic hydrogenation of benzene rings or heteroaromatic rings is the most direct and efficient means to synthesize compounds containing cycloalkyl or heterocyclic rings. However, the catalytic hydrogenation of benzene rings and heteroaromatic rings faces many challenges, including: (1) benzene rings and heteroaromatic rings are aromatic, and catalytic dearomatization requires overcoming very high energy barriers; (2) heterocyclic atom bonds of CO or CN in compounds are easily broken during catalytic hydrogenation, resulting in structural destruction; (3) stereoselectivity issues in hydrogenation reactions of polysubstituted (hetero)aromatic hydrocarbons.

[0003] In 1901, Sabatier and Senderens reported the first benzene hydrogenation reaction. Since then, a variety of catalytic systems have been developed, mainly focusing on catalysts based on precious metals such as Ru, Rh, Pd, and Pt. For example, in 2024, Yu Zhixiang's research group published in Organic Letters that a catalytic system composed of Rh / Pd and Rh / Pt purchased on the market was used to achieve the hydrogenation of aromatic compounds to prepare cyclohexane derivatives at room temperature and pressure. However, these catalytic processes often require the use of precious metals as catalysts, which is too expensive. Therefore, exploring the development of cheap and efficient catalysts is the trend of future development.

[0004] Compared with precious metals, non-precious metal-catalyzed hydrogenation of benzene rings is still very difficult. In 2023, Anand Narani, Kishore Natte and others reported that nitrogen-doped carbon-supported Co3O4 nanoparticles achieved catalytic hydrogenation of benzene rings and their derivatives, but a large amount of catalyst was required and the catalytic preparation was relatively complicated. Therefore, the development of a simple-to-operate catalytic system that can prepare (hetero)cycloalkane compounds from (hetero)aromatic hydrocarbons under mild reaction conditions with high selectivity, high activity, and a wide range of substrate applicability is of great significance both in science and in future industrialization. Summary of the invention

[0005] The main purpose of the present invention is to provide a metal catalyst and a preparation method and application thereof to overcome the deficiencies of the prior art.

[0006] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention includes:

[0007] An embodiment of the present invention provides a method for preparing a metal catalyst, which comprises: subjecting a mixed reaction system containing at least a metal salt, a co-catalyst, and an organic solvent to a first reaction, and then adding an alkaline substance to conduct a second reaction to obtain the metal catalyst.

[0008] The embodiment of the present invention also provides a metal catalyst prepared by the aforementioned preparation method.

[0009] The embodiments of the present invention also provide the use of the aforementioned metal catalyst in a catalytic hydrogenation reaction.

[0010] The embodiment of the present invention also provides a method for preparing cycloalkane compounds and / or saturated heterocyclic compounds by catalyzing hydrogenation reduction of aromatic compounds and / or heteroaromatic compounds, which comprises:

[0011] The metal catalyst is prepared by the aforementioned preparation method;

[0012] Furthermore, in a hydrogen atmosphere and under the action of the metal catalyst, the aromatic compound and / or heteroaromatic compound is subjected to a selective hydrogenation reaction to obtain a cycloalkane compound and / or a saturated heterocyclic compound.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] (1) The present invention prepares cheap metal catalysts in situ, does not require complex ligands or specific carriers, has simple catalyst synthesis steps, low preparation cost, convenient operation, and is easy to scale up;

[0015] (2) The hydrogenation reaction conditions in the present invention are mild, and highly selective hydrogenation of aromatic compounds and / or heteroaromatic compounds can be achieved at room temperature;

[0016] (3) The method provided by the present invention has a wide range of applications and can realize the preparation of a variety of cycloalkyl or saturated heterocyclic compounds with excellent industrial prospects. It has low requirements for equipment and has the potential for industrialization. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 is a gas chromatogram of the product in Example 1 of the present application;

[0019] Figure 2 This is the gas chromatogram of the product in Example 51 of the present application. DETAILED DESCRIPTION

[0020] In view of the defects of the prior art, the inventor of this case has proposed the technical solution of the present invention after long-term research and extensive practice. The technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] Specifically, as one aspect of the technical solution of the present invention, a method for preparing a metal catalyst involves: subjecting a mixed reaction system containing at least a metal salt, a co-catalyst, and an organic solvent to a first reaction, and then adding an alkaline substance to conduct a second reaction to obtain a metal catalyst.

[0022] In some preferred embodiments, the metal salt includes any one or more combinations of anhydrous cobalt chloride, cobalt chloride hexahydrate, anhydrous cobalt bromide, cobalt bromide hexahydrate, cobalt fluoride, cobalt iodide, cobalt iodide dihydrate, anhydrous cobalt carbonate, cobalt carbonate monohydrate, anhydrous cobalt acetate, cobalt acetate tetrahydrate, cobalt nitrate hexahydrate, cobalt acetylacetonate, cobalt sulfate, cobalt sulfate monohydrate, cobalt sulfate heptahydrate, elemental cobalt, cobalt hydroxide, nickel acetylacetonate, bis(1,5-cyclooctadiene)nickel, nickel acetate, nickel chloride, nickel bromide, dibromo(ethylene glycol dimethyl ether)nickel, and nickel trifluoromethanesulfonate, and is not limited thereto.

[0023] In some preferred embodiments, the co-catalyst includes any one or more combinations of borane, sodium borohydride, lithium borohydride, potassium borohydride, sodium triethylborohydride, lithium triethylborohydride, lithium aluminum tetrahydride, trimethylaluminum, diisobutylaluminum hydride, and borane ammonia, and is not limited thereto.

[0024] In some preferred embodiments, the organic solvent includes any one or more combinations of tetrahydrofuran, methyl tert-butyl ether, dioxane, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, methanol, ethanol, isopropanol, tert-butanol, cyclohexane, n-hexane, heptane, and methylcyclohexane, and is not limited thereto.

[0025] In some preferred embodiments, the alkaline substance includes any one or more combinations of potassium tert-butoxide, sodium tert-butoxide, lithium tert-butoxide, potassium methoxide, sodium methoxide, lithium methoxide, potassium ethoxide, sodium ethoxide, lithium ethoxide, and sodium hydride, and is not limited thereto.

[0026] In some preferred embodiments, the reaction temperature of the first reaction is 0 to 100° C., and the reaction time is 0.1 to 24 h.

[0027] In some preferred embodiments, the reaction temperature of the second reaction is 0 to 100° C., and the reaction time is 0.1 to 24 h.

[0028] In some preferred embodiments, the molar ratio of the metal salt, the promoter and the alkaline substance is 1-0.3:0.1-5:0.1-10.

[0029] Another aspect of the embodiments of the present invention further provides a metal catalyst prepared by the aforementioned preparation method.

[0030] The catalyst precursor used in the present invention is a non-precious metal salt, the reaction conditions are mild, the operation is simple, the prepared metal catalyst has a wide range of substrate applicability and good functional group tolerance, and has low requirements on equipment.

[0031] Another aspect of the embodiments of the present invention further provides the use of the aforementioned metal catalyst in a catalytic hydrogenation reaction.

[0032] Furthermore, the application includes the use of the metal catalyst in catalyzing the hydrogenation reduction of aromatic compounds and / or heteroaromatic compounds to prepare cycloalkane compounds and / or saturated heterocyclic compounds.

[0033] Another aspect of the embodiments of the present invention further provides a method for preparing cycloalkane compounds and / or saturated heterocyclic compounds by catalyzing hydrogenation reduction of aromatic compounds and / or heteroaromatic compounds, which comprises:

[0034] The metal catalyst is prepared by the aforementioned preparation method;

[0035] Furthermore, in a hydrogen atmosphere and under the action of the metal catalyst, the aromatic compound and / or heteroaromatic compound is subjected to a selective hydrogenation reaction to obtain a cycloalkane compound and / or a saturated heterocyclic compound.

[0036] In some preferred embodiments, the aryl compound and / or heteroaryl compound has a structure as shown in formula (I):

[0037]

[0038] Wherein, X is selected from C, N or O; R is selected from a mono-substituted or poly-substituted alkyl group with 1 to 20 carbon atoms, an ester group, a carboxylic acid, an amine group, an amide group, a hydroxyl group, an alcohol, an alkenyl group, an alkynyl group, an alkyl group, a benzene ring or a nitrogen heterocycle.

[0039] In some preferred embodiments, the method specifically comprises: subjecting aromatic compounds and / or heteroaromatic compounds to a selective hydrogenation reaction for 3 to 80 hours under the action of a metal catalyst at a hydrogen pressure of 0.1 to 20 MPa and a temperature of 0 to 200° C. to obtain cycloalkane compounds and / or saturated heterocyclic compounds.

[0040] Furthermore, the temperature is 0-120°C.

[0041] In some preferred embodiments, the molar ratio of the metal salt to the aromatic compound and / or heteroaromatic compound is 0.01-20:100.

[0042] In some preferred embodiments, the molar ratio of the co-catalyst to the aromatic compound and / or heteroaromatic compound is 0.01-40:100.

[0043] In some preferred embodiments, the molar ratio of the basic substance to the aromatic compound and / or heteroaromatic compound is 0.01-100:100.

[0044] In some more specific embodiments, the method for catalyzing the hydrogenation reduction of aromatic compounds and / or heteroaromatic compounds to prepare cycloalkane compounds and / or saturated heterocyclic compounds comprises:

[0045] The metal salt and the co-catalyst are subjected to the first stage reaction in an organic solvent; then an alkaline substance is added to carry out the second stage reaction; finally, an aromatic compound and / or a heteroaromatic compound is added, and the aromatic compound and / or the heteroaromatic compound is hydrogenated into the corresponding cycloalkane compound and / or saturated heterocyclic compound in a high-pressure reactor at a certain pressure, temperature and time.

[0046] In some more specific embodiments, the method for catalyzing the hydrogenation reduction of aromatic compounds and / or heteroaromatic compounds to prepare cycloalkane compounds and / or saturated heterocyclic compounds comprises:

[0047] A mixed reaction system comprising at least a metal salt, a co-catalyst, and an organic solvent is subjected to a first reaction, and then an alkaline substance is added to conduct a second reaction to obtain a metal catalyst;

[0048] In a high pressure reactor, an aryl compound and / or a heteroaryl compound is hydrogenated to a corresponding cycloalkane compound and / or a saturated heterocyclic compound using a metal catalyst at a certain pressure, temperature and reaction time.

[0049] Furthermore, the amount of the organic solvent used is 1-100 equivalents of the molar amount of the aromatic compound and / or heteroaromatic compound.

[0050] The technical solution of the present invention is further described in detail below in conjunction with several preferred embodiments and drawings. This embodiment is implemented on the premise of the technical solution of the invention, and a detailed implementation method and specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.

[0051] Unless otherwise specified, the experimental materials used in the following examples can be purchased from conventional biochemical reagent companies.

[0052] Example 1

[0053] This embodiment provides a method for preparing cycloalkanes or saturated heterocyclic compounds from aryl or heteroaryl compounds using metal catalysis at room temperature. The reaction process is as follows:

[0054]

[0055] CoCl2 (32 mg, 0.25 mmol), LiAlH4 (10 mg, 0.25 mmol) and dioxane (2 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, MeONa (46 mg, 0.85 mmol) and dioxane (2 mL) were added, and stirring was continued at room temperature for 1 h. Subsequently, dimethyl terephthalate (970 mg, 5 mmol, compound 1) and dioxane (4 mL) were added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-replaced 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and placed at room temperature for reaction for 24 h to obtain compound 2. Using mesitylene as the internal standard, the reaction solution was quantitatively analyzed by gas chromatography internal standard method, and the yield of dimethyl cyclohexanedicarboxylate 2 was 86%. The gas chromatogram of the product dimethyl cyclohexanedicarboxylate 2 is shown in the figure below: Figure 1 shown.

[0056] Embodiment 2 to Embodiment 9

[0057]

[0058] CoCl2 (0.025-0.05mmol), BH3·THF (0.05-0.06mmol) and dioxane (0.5mL) were placed in a reaction tube. After stirring at room temperature for 0.5h, t-BuOLi (0.075-0.17mmol) and dioxane (0.5mL) were added, and stirring was continued at room temperature for 1h. Subsequently, dimethyl terephthalate (97mg, 0.5mmol, compound 1) and dioxane (1mL) were added. The reaction tube was then placed in a 300mL reactor, and the reactor was gas-replaced 3 times with 2.0MPa H2. The reactor was filled with 5.0MPa H2 and placed in an oil bath for reaction to obtain compound 2. Using mesitylene as the internal standard, the reaction solution was quantitatively analyzed by gas chromatography internal standard method.

[0059] The difference between Examples 2N9 is that the amounts of CoCl2, BH3·THF and t-BuOLi used are different, and the reaction temperature and time are different. The specific reaction conditions corresponding to Examples 2 to 9 and the yield of dimethyl 1,4-cyclohexanedicarboxylate 2 are shown in Table 1.

[0060] Table 1 Specific reaction conditions corresponding to Examples 2 to 9 and the yield of dimethyl 1,4-cyclohexanedicarboxylate 2

[0061]

[0062]

[0063] Embodiment 10 to Embodiment 15

[0064]

[0065] CoCl2 (3.2 mg, 0.025 mmol), a cocatalyst (0.05 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOLi (6.8 mg, 0.085 mmol) and dioxane (0.5 mL) were added, and stirring was continued at room temperature for 1 h. Subsequently, dimethyl terephthalate (97 mg, 0.5 mmol, compound 1) and dioxane (1 mL) were added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-exchanged 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and placed at room temperature for reaction for 24 h to obtain compound 2. Using mesitylene as an internal standard, the reaction solution was quantitatively analyzed by gas chromatography internal standard method.

[0066] The difference between Examples 10 to 15 is that different co-catalysts are used. The specific reaction conditions corresponding to Examples 10 to 15 and the yield of dimethyl 1,4-cyclohexanedicarboxylate 2 are shown in Table 2.

[0067] Table 2 Specific reaction conditions corresponding to Example 10N15 and yield of dimethyl 1,4-cyclohexanedicarboxylate 2

[0068] name Type and dosage of co-catalyst 2 Yield Example 10 <![CDATA[BH3·THF(50μL)]]> 64％ Embodiment 11 <![CDATA[NaHBEt3(50μL)]]> 59％ Example 12 <![CDATA[NaBH4(1.9mg)]]> 53％ Example 13 <![CDATA[LiBH4(1.1mg)]]> 58％ Embodiment 14 <![CDATA[LiAlH4(2.3mg)]]> 75％ Embodiment 15 DIBAL-H (50 μL) 62％

[0069] Example 16 to Example 25

[0070]

[0071] Metal salt (0.025mmol), LiAlH4 (0.05mmol) and dioxane (0.5mL) were placed in a reaction tube. After stirring at room temperature for 0.5h, t-BuOLi (6.8mg, 0.085mmol) and dioxane (0.5mL) were added, and stirring was continued at room temperature for 1h. Subsequently, dimethyl terephthalate (97mg, 0.5mmol, compound 1) and dioxane (1mL) were added. The reaction tube was then placed in a 300mL reactor, and the reactor was gas-exchanged 3 times with 2.0MPa H2. The reactor was filled with 5.0MPa H2 and placed at room temperature for reaction for 24h to obtain compound 2. Using mesitylene as an internal standard, the reaction solution was quantitatively analyzed by gas chromatography internal standard method.

[0072] The difference between Examples 16 to 25 is that different metal salts are used. The specific reaction conditions corresponding to Examples 16 to 25 and the yield of dimethyl 1,4-cyclohexanedicarboxylate 2 are shown in Table 3.

[0073] Table 3 Specific reaction conditions corresponding to Examples 16 to 25 and yield of dimethyl 1,4-cyclohexanedicarboxylate 2

[0074] Group Type and dosage of metal salt 2 Yield Example 16 <![CDATA[Ni(acac)2(50μL)]]> 56％ Embodiment 17 <![CDATA[Ni(COD)2(50μL)]]> 51％ Embodiment 18 <![CDATA[NiOAc2(1.9mg)]]> 50％ Embodiment 19 <![CDATA[NiCl2(1.1mg)]]> 50％ Embodiment 20 <![CDATA[NiBr2·dme(2.3mg)]]> 51％ Embodiment 21 <![CDATA[NiOTf2(50μL)]]> 60％ Embodiment 22 <![CDATA[CoBr2(5.5mg)]]> 66％ Embodiment 23 <![CDATA[CoOAc2(4.4mg)]]> 55％ Embodiment 24 <![CDATA[Co(acac)3(8.9mg)]]> 70％ Embodiment 25 <![CDATA[CoCl2·6H2O(5.9mg)]]> 72％

[0075] Example 26 to Example 36

[0076]

[0077] CoCl2 (0.0125-0.025 mmol), LiAlH4 (0.0125-0.05 mmol) and solvent (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOLi (0.0425-0.085 mmol) and solvent (0.5 mL) were added and continued to stir at room temperature for 1 h. Subsequently, dimethyl terephthalate (97 mg, 0.5 mmol, compound 1) and solvent (1 mL) were added. Then the reaction was stirred at room temperature for 0.5 h. Tube Placement In a 300 mL reactor, 2.0 MPa H2 was used to replace the gas in the reactor three times, and the reactor was filled with H2 and reacted at room temperature for 24 h to obtain compound 2. Mesitylene was used as an internal standard, and the reaction solution was quantitatively analyzed by gas chromatography internal standard method.

[0078] The difference between Example 26N36 is that the amount of CoCl2, LiAlH4, t-BuOLi used is different, the solvent used is different, and the hydrogen pressure is different. The specific reaction conditions corresponding to Example 26N36 and the yield of dimethyl 1,4-cyclohexanedicarboxylate 2 are shown in Table 4.

[0079] Table 4 Specific reaction conditions corresponding to Examples 26 to 36 and the yield of dimethyl 1,4-cyclohexanedicarboxylate 2

[0080] name <![CDATA[Dosage of CoCl2]]> <![CDATA[Dosage of LiAlH4]]> t-BuOLi dosage Solvents <![CDATA[H2 pressure]]> 2 Yield Embodiment 26 3.2mg 1mg 6.8mg dioxane 5.0MPa 81％ Embodiment 27 3.2mg 1mg 6.8mg THF 5.0MPa 60％ Embodiment 28 3.2mg 0.5mg 6.8mg dioxane 5.0MPa 80％ Embodiment 29 3.2mg 1mg 6mg dioxane 5.0MPa 78％ Embodiment 30 3.2mg 1mg 4mg dioxane 5.0MPa 72％ Embodiment 31 2.6mg 0.8mg 5.4mg dioxane 5.0MPa 72％ Embodiment 32 1.6mg 0.5mg 3.4mg dioxane 5.0MPa 67％ Embodiment 33 3.2mg 1mg 6.8mg dioxane 4.0MPa 78％ Embodiment 34 3.2mg 1mg 6.8mg dioxane 3.0MPa 73％ Embodiment 35 3.2mg 1mg 6.8mg dioxane 2.0MPa 67％ Embodiment 36 3.2mg 1mg 6.8mg dioxane 1.0MPa 51％

[0081] Example 37 to Example 42

[0082]

[0083] CoCl2 (3.2 mg, 0.025 mmol), LiAlH4 (1 mg, 0.025 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, alkali (0.085 mmol) and dioxane (0.5 mL) were added, and stirring was continued at room temperature for 1 h. Subsequently, dimethyl terephthalate (97 mg, 0.5 mmol, compound 1) and dioxane (1 mL) were added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-exchanged 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and placed at room temperature for reaction for 24 h to obtain compound 2. Using mesitylene as an internal standard, the reaction solution was quantitatively analyzed by gas chromatography internal standard method.

[0084] The difference between Examples 37 to 42 is that different bases are used. The specific reaction conditions corresponding to Examples 37 to 42 and the yield of dimethyl 1,4-cyclohexanedicarboxylate 2 are shown in Table 5.

[0085] Table 5 Specific reaction conditions corresponding to Examples 37 to 42 and the yield of dimethyl 1,4-cyclohexanedicarboxylate 2

[0086] Group Type and amount of alkali 2 Yield Embodiment 37 t-BuOK(9.5mg) 74％ Embodiment 38 t-BuONa(8.2mg) 74％ Embodiment 39 MeONa (4.6 mg) 79％ Embodiment 40 MeOK (6.0 mg) 53％ Embodiment 41 EtONa (5.8 mg) 82％ Embodiment 42 MeOLi (3.2 mg) 54％

[0087] Embodiment 43

[0088]

[0089] CoCl2 (3.2 mg, 0.025 mmol), NaBH4 (1.9 mg, 0.05 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOLi (6.8 mg, 0.085 mmol) and dioxane (0.5 mL) were added, and stirring was continued at room temperature for 1 h. Subsequently, terephthalic acid (69 mg, 0.5 mmol, compound 3) and THF (1 mL) were added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-substituted 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and placed in a 100 ° C oil bath for 11 h to obtain compound 4. Using mesitylene as an internal standard, the reaction solution was quantitatively analyzed by gas chromatography internal standard method, and the yield of 1,4-cyclohexanedimethanol 4 was 57%.

[0090] Embodiment 44

[0091] This embodiment provides a method for preparing (hetero)cycloalkanes by metal-catalyzed hydrogenation of (hetero)aromatics under room temperature conditions. The reaction process is as follows:

[0092]

[0093] CoCl2 (3.2 mg, 0.025 mmol), BH3·THF (50 μL, 0.05 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOLi (6.8 mg, 0.085 mmol) and dioxane (0.5 mL) were added, and stirring was continued at room temperature for 1 h. Subsequently, phenol (47 mg, 0.5 mmol, compound 5) and dioxane (1 mL) were added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-replaced 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and reacted at room temperature for 24 h to obtain compound 6. The reaction solution was quantified by gas chromatography normalization, and the yield of 1-hydroxy-cyclohexane 6 was 88%.

[0094] Embodiment 45

[0095] This embodiment provides a method for preparing (hetero)cycloalkanes by metal-catalyzed hydrogenation of (hetero)aromatics under room temperature conditions. The reaction process is as follows:

[0096]

[0097] CoCl2 (3.2 mg, 0.025 mmol), BH3·THF (50 μL, 0.05 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOLi (6.8 mg, 0.085 mmol) and dioxane (0.5 mL) were added, and stirring was continued at room temperature for 1 h. Ethylbenzene (53 mg, 0.5 mmol, compound 7) and dioxane (1 mL) were then added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-replaced 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and reacted at room temperature for 24 h to obtain compound 8. The reaction solution was quantified by gas chromatography normalization, and the yield of 1-ethyl-cyclohexane 8 was 91%.

[0098] Embodiment 46

[0099] This embodiment provides a method for preparing (hetero)cycloalkanes by metal-catalyzed hydrogenation of (hetero)aromatics under room temperature conditions. The reaction process is as follows:

[0100]

[0101] CoCl2 (3.2 mg, 0.025 mmol), BH3·THF (50 μL, 0.05 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOLi (6.8 mg, 0.085 mmol) and dioxane (0.5 mL) were added, and stirring was continued at room temperature for 1 h. Dibenzylamine (99 mg, 0.5 mmol, compound 9) and dioxane (1 mL) were subsequently added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-replaced 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and reacted at 150 ° C for 12 h to obtain compound 10. The reaction solution was quantified by gas chromatography normalization, and the yield of di(cyclohexylmethyl)amine 10 was 98%.

[0102] Embodiment 47

[0103] This embodiment provides a method for preparing (hetero)cycloalkanes by metal-catalyzed hydrogenation of (hetero)aromatics under room temperature conditions. The reaction process is as follows:

[0104]

[0105] CoCl2 (3.2 mg, 0.025 mmol), BH3·THF (50 μL, 0.05 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOLi (6.8 mg, 0.085 mmol) and dioxane (0.5 mL) were added, and stirring was continued at room temperature for 1 h. Biphenyl (77.1 mg, 0.5 mmol, compound 11) and dioxane (1 mL) were subsequently added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-substituted 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and reacted at 150 ° C for 12 h to obtain compound 12. The reaction solution was quantified by gas chromatography normalization, and the yield of cyclohexylbenzene 12 was 70%.

[0106] Embodiment 48

[0107] This embodiment provides a method for preparing (hetero)cycloalkanes by metal-catalyzed hydrogenation of (hetero)aromatics under room temperature conditions. The reaction process is as follows:

[0108]

[0109] CoCl2 (3.2 mg, 0.025 mmol), BH3·THF (50 μL, 0.05 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOLi (6.8 mg, 0.085 mmol) and dioxane (0.5 mL) were added, and stirring was continued at room temperature for 1 h. Aniline (46.5 mg, 0.5 mmol, compound 13) and dioxane (1 mL) were subsequently added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-replaced 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and reacted at 60 ° C for 8 h to obtain compound 14. The reaction solution was quantified by gas chromatography normalization, and the yield of cyclohexylamine 14 was 23%.

[0110] Embodiment 49

[0111] This embodiment provides a method for preparing (hetero)cycloalkanes by metal-catalyzed hydrogenation of (hetero)aromatics under room temperature conditions. The reaction process is as follows:

[0112]

[0113] CoCl2 (3.2 mg, 0.025 mmol), BH3·THF (50 μL, 0.05 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOLi (6.8 mg, 0.085 mmol) and dioxane (0.5 mL) were added, and stirring was continued at room temperature for 1 h. Benzyl alcohol (54.1 mg, 0.5 mmol, compound 15) and dioxane (1 mL) were then added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-replaced 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and reacted at 60 ° C for 8 h to obtain compound 16. The reaction solution was quantified by gas chromatography normalization, and the yield of cyclohexylmethanol 16 was 93%.

[0114] Embodiment 50

[0115] This embodiment provides a method for preparing (hetero)cycloalkanes by metal-catalyzed hydrogenation of (hetero)aromatics under room temperature conditions. The reaction process is as follows:

[0116]

[0117] CoCl2 (3.2 mg, 0.025 mmol), BH3·THF (50 μL, 0.05 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOLi (6.8 mg, 0.085 mmol) and dioxane (0.5 mL) were added, and stirring was continued at room temperature for 1 h. Subsequently, quinoline (64.6 mg, 0.5 mmol, compound 17) and dioxane (1 mL) were added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-replaced 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and reacted at 150 ° C for 12 h to obtain compound 18. The reaction solution was quantified by gas chromatography normalization, and the yield of decahydroquinoline 18 was 76%.

[0118] Embodiment 51

[0119]

[0120] CoCl2 (3.2 mg, 0.025 mmol), BH3·THF (50 μL, 0.05 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOLi (6.8 mg, 0.085 mmol) and dioxane (0.5 mL) were added, and stirring was continued at room temperature for 1 h. Subsequently, 2-methylquinoline (71.6 mg, 0.5 mmol, compound 19) and dioxane (1 mL) were added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-substituted 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and reacted at 150 ° C for 12 h to obtain compounds 20, 21, and 22. Using n-decane as the internal standard, the reaction solution was quantitatively analyzed by gas chromatography internal standard method. The yield of decahydroquinoline 20 was 19%, the yield of 5,6,7,8-tetrahydro-2-methylquinoline 21 was 62%, and the yield of 1,2,3,4-tetrahydro-2-methylquinoline 22 was 18%. The gas chromatogram of the product 1,2,3,4-tetrahydro-2-methylquinoline 22 is shown in Figure 2 shown.

[0121] Embodiment 52

[0122]

[0123] CoCl2 (3.2 mg, 0.025 mmol), BH3·THF (50 μL, 0.05 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOK (9.5 mg, 0.085 mmol) and dioxane (0.5 mL) were added, and stirring was continued at room temperature for 1 h. Subsequently, 2-methylquinoline (71.6 mg, 0.5 mmol, compound 19) and dioxane (1 mL) were added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-substituted 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and reacted at 150 ° C for 12 h to obtain compounds 20, 21, and 22. The reaction solution was quantitatively analyzed by gas chromatography internal standard method using n-decane as internal standard. The yield of decahydroquinoline 20 was 2%, the yield of 5,6,7,8-tetrahydro-2-methylquinoline 21 was 17%, and the yield of 1,2,3,4-tetrahydro-2-methylquinoline 22 was 80%.

[0124] Embodiment 53

[0125]

[0126] CoCl2 (3.2 mg, 0.025 mmol), BH3·THF (50 μL, 0.05 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOK (9.5 mg, 0.085 mmol) and dioxane (0.5 mL) were added, and stirring was continued at room temperature for 1 h. Bipyridine (78.1 mg, 0.5 mmol, compound 23) and dioxane (1 mL) were subsequently added. The reaction tube was then placed in a 300 mL reactor, and the reactor was gas-substituted 3 times with 2.0 MPa H2. The reactor was filled with 5.0 MPa H2 and reacted at 150 ° C for 12 h to obtain compound 24. The reaction solution was quantified by gas chromatography normalization, and the yield of 2,2-bipiperidine 24 was 98%.

[0127] Embodiment 54

[0128]

[0129] CoCl2 (3.2 mg, 0.025 mmol), BH3·THF (50 μL, 0.05 mmol) and dioxane (0.5 mL) were placed in a reaction tube. After stirring at room temperature for 0.5 h, t-BuOK (9.5 mg, 0.085 mmol) and dioxane (0.5 mL) were added and continued to stir at room temperature for 1 h. Benzofuran (59 mg, 0.5 mmol, compound 25) and dioxane (1 mL) were then added. The reaction mixture was stirred for 0.5 h at room temperature. Tube Placement In a 300 mL reactor, the reactor was gas-substituted three times with 2.0 MPa H2, and the reactor was filled with 2.0 MPa H2 and reacted at 50° C. for 12 h to obtain compound 26. The reaction solution was quantified by gas chromatography normalization, and the yield of dihydrobenzofuran 26 was 98%.

[0130] In addition, the inventors of this case also referred to the aforementioned embodiments and conducted experiments with other raw materials, process operations, and process conditions described in this specification, and obtained relatively ideal results.

[0131] It should be understood that the technical solution of the present invention is not limited to the above-mentioned specific implementation cases. Any technical deformation made according to the technical solution of the present invention without departing from the scope of protection of the purpose of the present invention and the claims shall fall within the protection scope of the present invention.

Claims

1. A method for preparing a metal catalyst, characterized in that: include: A mixed reaction system containing at least a metal salt, a co-catalyst and an organic solvent is subjected to a first reaction, and then an alkaline substance is added to conduct a second reaction to obtain a metal catalyst.

2. The preparation method according to claim 1, characterized in that: The metal salt includes any one or more combinations of anhydrous cobalt chloride, cobalt chloride hexahydrate, anhydrous cobalt bromide, cobalt bromide hexahydrate, cobalt fluoride, cobalt iodide, cobalt iodide dihydrate, anhydrous cobalt carbonate, cobalt carbonate monohydrate, anhydrous cobalt acetate, cobalt acetate tetrahydrate, cobalt nitrate hexahydrate, cobalt acetylacetonate, cobalt sulfate, cobalt sulfate monohydrate, cobalt sulfate heptahydrate, elemental cobalt, cobalt hydroxide, nickel acetylacetonate, bis(1,5-cyclooctadiene)nickel, nickel acetate, nickel chloride, nickel bromide, nickel dibromo(ethylene glycol dimethyl ether), and nickel trifluoromethanesulfonate; And / or, the co-catalyst includes any one or more combinations of borane, sodium borohydride, lithium borohydride, potassium borohydride, sodium triethylborohydride, lithium triethylborohydride, lithium aluminum tetrahydride, trimethylaluminum, diisobutylaluminum hydride, and borane ammonia; And / or, the organic solvent includes any one or more combinations of tetrahydrofuran, methyl tert-butyl ether, dioxane, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, methanol, ethanol, isopropanol, tert-butanol, cyclohexane, n-hexane, heptane, and methylcyclohexane; And / or, the alkaline substance includes any one or more combinations of potassium tert-butoxide, sodium tert-butoxide, lithium tert-butoxide, potassium methoxide, sodium methoxide, lithium methoxide, potassium ethoxide, sodium ethoxide, lithium ethoxide, and sodium hydride.

3. The preparation method according to claim 1, characterized in that: The reaction temperature of the first reaction is 0 to 100° C. and the reaction time is 0.1 to 24 h; And / or, the reaction temperature of the second reaction is 0 to 100° C. and the reaction time is 0.1 to 24 h; And / or, the molar ratio of the metal salt, the promoter and the alkaline substance is 1-0.3:0.1-5:0.1-10.

4. A metal catalyst prepared by the preparation method according to any one of claims 1 to 3.

5. Use of the metal catalyst described in claim 4 in catalytic hydrogenation reaction.

6. The use according to claim 5, characterized in that: The application includes the application of the metal catalyst in catalyzing the hydrogenation reduction of aromatic compounds and / or heteroaromatic compounds to prepare cycloalkane compounds and / or saturated heterocyclic compounds.

7. A method for preparing cycloalkane compounds and / or saturated heterocyclic compounds by catalytic hydrogenation reduction of aromatic compounds and / or heteroaromatic compounds, characterized in that: include: The metal catalyst is prepared by the preparation method according to any one of claims 1 to 3; Furthermore, in a hydrogen atmosphere and under the action of the metal catalyst, the aromatic compound and / or heteroaromatic compound is subjected to a selective hydrogenation reaction to obtain a cycloalkane compound and / or a saturated heterocyclic compound.

8. The method according to claim 7, characterized in that: The aromatic compound and / or heteroaromatic compound has a structure as shown in formula (I): Wherein, X is selected from C, N or O; R is selected from a mono-substituted or poly-substituted alkyl group with 1 to 20 carbon atoms, an ester group, a carboxylic acid, an amine group, an amide group, a hydroxyl group, an alcohol, an alkenyl group, an alkynyl group, an alkyl group, a benzene ring or a nitrogen heterocycle.

9. The method according to claim 7, characterized in that: Specifically include: Under the conditions of hydrogen pressure of 0.1-20 MPa and temperature of 0-200° C., the aromatic compound and / or heteroaromatic compound is subjected to selective hydrogenation reaction for 3-80 hours under the action of a metal catalyst to obtain a cycloalkane compound and / or a saturated heterocyclic compound.

10. The method according to claim 7, characterized in that: The molar ratio of the metal salt to the aromatic compound and / or heteroaromatic compound is 0.01 to 20:100; and / or, the molar ratio of the co-catalyst to the aromatic compound and / or heteroaromatic compound is 0.01 to 40:100; And / or, the molar ratio of the basic substance to the aromatic compound and / or heteroaromatic compound is 0.01 to 100:100.

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