Anti-Martensite hydroamination method of aluminum-catalyzed aromatic olefin

Abstract

The invention discloses a method for realizing anti-Martensite hydroamination addition of unactivated aromatic olefin under catalysis of a novel organic aluminum catalyst, and belongs to the field of organic chemistry. The aluminum catalyst disclosed by the invention is synthesized by using the existing ligand and the commercially available aluminum alkyl compound, and the synthesis steps are simple and easy to operate. Under the action of the aluminum catalyst and the additive, aromatic olefin reacts with different amines in the organic solvent, and a series of amine compounds are obtained with good regioselectivity and high yield. According to the method, the main group metal aluminum catalyst which is low in cost and easy to obtain is used, and the olefin anti-Martensite hydroamination addition product is synthesized with excellent regioselectivity under relatively mild and simple reaction conditions.

Description

Technical Field

[0001] The method of the invention belongs to the field of organic chemistry and uses an aluminum catalyst supported by a beta-diketoimine ligand to realize the hydrogen amination reaction of aromatic olefins. Background Art

[0002] Amine compounds are an important chemical substance because they play an important role in the fields of biology, medicine, materials and energy. So far, many synthetic methods for constructing CN bonds have been studied, such as coupled amination reaction, addition reaction of amines and isocyanates, Diels-Alder reaction of nitrogen-containing enamines, reaction of hydroxylamines and aldehydes / ketones, alkylation reaction of amines, olefin hydroamination reaction, etc. However, these synthetic methods all have some defects, for example, they require precious metal catalysts or harsh reaction conditions, and some methods even have high requirements for reaction reagents, such as pre-activated or some more dangerous reactants. Therefore, it is necessary to develop a new and efficient method for synthesizing amines. Compared with other types of reactions for constructing CN bonds, the hydroamination reaction of olefins is one of the most efficient, environmentally friendly and economical synthetic methods due to its easy availability of raw materials, atom economy and environmental friendliness.

[0003] However, due to the low reactivity and electron cloud density of carbon-carbon double bonds, it is difficult for unactivated olefins to undergo hydroamination. At the same time, the regioselectivity of the reaction is a great challenge. Currently, researchers have successfully synthesized many N-containing organic compounds using catalytic hydroamination technology, and on the basis of achieving high yields, they can synthesize the products of anti-Markovnikov hydroamination addition with high regioselectivity. However, these reactions usually use catalysts such as Ni (C. Lee, H. Kang, S. Hong, Chem. Sci. 2024, 15, 442-457.), Ru (J. Takaya, JF Hartwig, J. Am. Chem. Soc. 2005, 127, 16, 5756-5757.), Ir (K. Sedillo, F. Fan, RR Knowles, AG Doyle, J. Am. Chem. Soc. 2024, 146, 29, 20349-20356.), La (J.-S. Ryu, GY Li, TJ Marks, J. Am. Chem. Soc. 2003, 125, 41, 12584-12605.), which not only increases the cost, but also the catalyst is easily deactivated and difficult to recover.

[0004] Therefore, it is of great value to develop a new type of low-cost, easy-to-synthesize and green catalyst, especially a catalyst for the trans-hydroamination reaction of olefins. Summary of the invention

[0005] The invention aims to provide a novel method for synthesizing amine compounds. The raw materials of the method are cheap and readily available, the catalyst is green and environmentally friendly, the yield is good and the substrate range is relatively wide, and the method has certain industrial application prospects.

[0006] The present invention achieves one of the above purposes by adopting the following technical solution:

[0007] A method for the anti-Markovnikov hydroamination of aromatic olefins catalyzed by aluminum comprises the following steps:

[0008] In an inert gas, the catalyst [Al] and additives are dissolved in an organic solvent, and then olefin is added. and amine compounds Ar 2 -NH2, after the temperature reaction is completed, a reaction mixture is obtained, and the target product is obtained by post-treatment and purification.

[0009] Among them, Ar 1 ,Ar 2 is an aryl group or a heteroaryl group.

[0010] The catalyst [Al] used is a compound having the following structural formula:

[0011]

[0012] This method provides a preparation method of the catalyst:

[0013] Under an inert atmosphere, an organic solution of β-diketoimines ligand LH and trimethylaluminum is reacted in an organic solvent at 0°C, and the reaction mixture is reacted at room temperature to obtain a turbid liquid of an aluminum methyl compound stabilized with a β-diketoimines ligand. The aluminum methyl compound stabilized with a β-diketoimines ligand is filtered out of the system, washed with an organic solvent, and dried to obtain a white solid.

[0014] Among them, the structural formula of β-diketimine ligand LH is:

[0015]

[0016] According to some preferred embodiments of the present invention, the reaction process is always under an inert atmosphere.

[0017] According to some preferred embodiments of the present invention, the reaction is firstly carried out at 0° C. for 0.05 to 0.5 hours and then at room temperature for 18 to 24 hours.

[0018] The preparation method according to claim 3 is characterized in that the molar ratio of the β-diketoimine ligand LH to the organic solution of trimethylaluminum is 1:1.2 to 1:3, and the concentration of trimethylaluminum in the organic solution of trimethylaluminum is 1 mol / L.

[0019] The preparation method according to claim 3 is characterized in that: the organic solvents are all selected from n-hexane.

[0020] The preparation method according to claim 3, characterized in that the ratio of the amount of the substance containing the β-diketimine ligand LH to the volume of the organic solvent is 0.5 mmol / mL.

[0021] The reaction process is as follows:

[0022]

[0023] According to some preferred embodiments of the present invention, the organic solvent is one or two of 1,4-dioxane, tetrahydrofuran, tert-butyl methyl ether, chlorobenzene, and dimethyl sulfoxide; and the ratio of the amount of the amine compound to the volume of the organic solvent is 0.25 to 0.5 mmol / mL.

[0024] According to some preferred embodiments of the present invention, the aluminum-catalyzed anti-Markovnikov hydroamination method of aromatic olefins is characterized in that the molar ratio of the amine compound to the olefin is 1:2 to 1:5.

[0025] According to some preferred embodiments of the present invention, the aluminum-catalyzed anti-Markovnikov hydroamination method of aromatic olefins is characterized in that the molar amount of the catalyst [Al] is 1 to 15% of the molar amount of the amine compound.

[0026] According to some preferred embodiments of the present invention, the aluminum-catalyzed anti-Markovnikov hydroamination method of aromatic olefins is characterized in that the temperature-raising reaction conditions refer to the use of magnetic stirring, the temperature is 60°C or 90°C, and the time is 4 to 48 hours.

[0027] The present invention has the following beneficial effects:

[0028] 1. The olefins and amines used in the present invention are unactivated compounds with a wide range of sources, which can significantly reduce production costs. This not only improves the operability of the reaction, but also provides a new solution for green chemistry.

[0029] 2. The catalyst of the present invention does not contain transition metals, but uses main group metal aluminum, which is abundant, cheap and non-toxic, and has a simple preparation process and has prospects for large-scale industrial application.

[0030] 3. The present invention has general applicability to a wide range of substrates and can generate anti-Markovnikov hydroamination products with good selectivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the structure of the catalyst obtained in the present invention. DETAILED DESCRIPTION

[0032] The following detailed description will help to more deeply understand the characteristics and advantages of the present invention. The embodiments provided are only used to illustrate the method of the present invention and are not intended to limit the other contents of the present invention in any way. All reasonable changes and combinations included within the scope of the inventive concept of the present invention fall within the protection scope of the present invention.

[0033] 1. According to the technical solution of the present invention, a method for preparing an aluminum catalyst [Al] for catalyzing anti-Markovnikov hydroamination of aromatic olefins comprises:

[0034] Under an inert atmosphere, the β-diketoimine ligand LH and an organic solution of trimethylaluminum are reacted in an organic solvent at 0°C, and then the reaction mixture is reacted at room temperature. The reaction process is as follows:

[0035]

[0036] A white turbid liquid of an aluminum methyl compound stabilized by a β-diketoimines ligand is obtained. The aluminum methyl compound stabilized by a β-diketoimines ligand is filtered out from the system, washed with an organic solvent, and vacuum dried to obtain a white solid.

[0037] 2. Preparation of anti-Markovnikov hydroamination products from aromatic olefins and amines:

[0038] Under the protection of inert gas, the catalyst [Al] and additives are dissolved in an organic solvent, and then olefin is added. and amine compounds Ar 2 -NH2, the molar ratio of the amine compound to the additive is 1:2, the molar amount of the catalyst [Al] is 1-15% of the molar amount of the amine compound, the ratio of the amount of the amine compound to the volume of the organic solvent is 0.25-0.5 mmol / mL, the molar ratio of the amine compound to the olefin is 1:2-1:5, magnetic stirring is adopted, the temperature is 60°C or 90°C, the time is 4-48h, and after the reaction is completed, post-treatment is performed to obtain an anti-Markovnikov hydrogen amination product.

[0039] In the following examples, THF refers to tetrahydrofuran, Dioxane refers to 1,4-dioxane, and equiv. refers to equivalents. r is defined as the target product. Secondary anti-Markovnikov hydroamination addition product with by-product ratio of production.

[0040] After the reaction, an internal standard was added, and the yield and r value of the product were calculated by hydrogen nuclear magnetic resonance spectrum.

[0041] 1. Example of Preparation of Catalyst

[0042] Example 1

[0043] The catalyst is prepared by the following process:

[0044] At 0°C, an organic solution of trimethylaluminum is dropped into an organic solvent of β-diketone imine ligand LH in n-hexane. After stirring for 0.05 to 0.5 hours, the reaction mixture is slowly heated to room temperature and continued to be stirred for 18 to 24 hours. The residue is filtered and washed with an organic solvent of n-hexane until the product becomes a white solid.

[0045] After testing, the yield of the catalyst crystals was 81%. The results of characterization of its structure by nuclear magnetic hydrogen spectrum and carbon spectrum are as follows:

[0046] 1 H NMR (400MHz, Benzene-d6) δ6.77(t,J=8.3Hz,2H),6.23(d,J=8.3Hz,4H),4.99(s,1H),3.27(s,12H),1.72(s,6H),-0.65(s,6H).

[0047] 13 C NMR (101MHz, Chloroform-d) δ168.02,153.87,124.59,123.37,104.19,96.48,55.16,54.85,21.64.

[0048] The filtrate was concentrated and then crystallized at room temperature to obtain white crystals. The diffraction data of the catalyst crystals obtained by Bruker D8 Venture X-ray single crystal diffractometer and OLEX2 software showed that the aluminum center and the ligand in the crystal formed a distorted six-membered ring structure, two nitrogen atoms and two methyl carbon atoms jointly stabilized the aluminum atom, and the central aluminum formed a four-coordinated positive trivalent metal center with catalytic activity. The specific single crystal structure is shown in the attached Figure 1 shown.

[0049] 2. Example of Hydroamination Reaction

[0050] Example 2.1

[0051] The catalytic reaction proceeds through the following process:

[0052] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by aniline (0.0233g, 0.25mmol) and styrene (0.1302g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 21 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after being dissolved in CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after being dissolved in CDCl3. The relevant data of the obtained product are as follows:

[0053] The yield of the anti-Markovnikov hydroamination product was 90%, r=91:9.

[0054] 1 H NMR (400MHz, Chloroform-d) δ7.20–6.89(m,7H),6.60–6.45(m,1H),6.42–6.29(m,2H),3.37(s,1H),3.11(t,J=7.1Hz,2H),2.62(t,J=7.1Hz,2H).

[0055] 13 C NMR (101MHz, Chloroform-d) δ148.42,139.79,129.68,129.18,128.97,126.78,117.76,113.35,45.36,35.84.

[0056] Example 2.2

[0057] The catalytic reaction proceeds through the following process:

[0058] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by 2-methylaniline (0.0268g, 0.25mmol) and styrene (0.1302g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 21 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after being dissolved in CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after being dissolved in CDCl3. The relevant data of the obtained product are as follows:

[0059] The yield of the anti-Markovnikov hydroamination product was 78%, r=78:0.

[0060] 1 H NMR(400MHz,Chloroform-d)δ7.29–7.00(m,6H),6.94(d,J=7.2Hz,1H),6.57(d,J= 7.6Hz,2H),3.42(s,1H),3.34(t,J=7.0Hz,2H),2.86(t,J=6.9Hz,2H),1.92(s,3H).

[0061] 13 C NMR(101MHz,Chloroform-d)δ144.92,138.34,129.08,129.07,127.76,127.74,127.58, 127.57,126.11,125.41,121.04,115.98,115.97,108.85,108.83,43.92,34.45,16.25.

[0062] Example 2.3

[0063] The catalytic reaction proceeds through the following process:

[0064] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by 2-methoxyaniline (0.0308g, 0.25mmol) and styrene (0.1302g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 21 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after being dissolved in CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after being dissolved in CDCl3. The relevant data of the obtained product are as follows:

[0065] The yield of the anti-Markovnikov hydroamination product was 84%, r=84:0.

[0066] 1 H NMR(400MHz,Chloroform-d)δ7.32–7.03(m,5H),6.79(t,J=7.6Hz,1H),6.74–6.4 7(m,3H),4.21(s,1H),3.70(s,3H),3.30(t,J=7.3Hz,2H),2.84(t,J=7.3Hz,2H).

[0067] 13 C NMR (101MHz, Chloroform-d) δ145.87,138.49,136.99,127.72,127.46,125.26,120.30,115.44,108.92,108.54,54.37,43.99,34.65.

[0068] Example 2.4

[0069] The catalytic reaction proceeds through the following process:

[0070] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by 3-bromoaniline (0.0430g, 0.25mmol) and styrene (0.1302g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 21 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after being dissolved in CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after being dissolved in CDCl3. The relevant data of the obtained product are as follows:

[0071] The yield of the anti-Markovnikov hydroamination product was 52%, r=95:5.

[0072] 1 H NMR(500MHz,Chloroform-d)δ7.31(td,J=8.0,7.6,1.9Hz,2H),7.26–7.20(m,1H),7.22–7.17(m,2H),6.98(td,J=8.0,1.5Hz,1H),6.7 9(dd,J=7.9,2.0Hz,1H),6.71(t,J=2.0Hz,1H),6.47(dd,J=8.2,2.3Hz,1H),3.70(s,1H),3.34(t,J=7.0Hz,2H),2.88(t,J=7.0Hz,2H).

[0073] 13 C NMR (126MHz, Chloroform-d) δ149.34,138.99,130.56,128.81,128.73,126.62,123.38,120.17,115.44,111.72,44.79,35.34.

[0074] Example 2.5

[0075] The catalytic reaction proceeds through the following process:

[0076] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by 3-methylaniline (0.0268g, 0.25mmol) and styrene (0.1302g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 21 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after being dissolved in CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after being dissolved in CDCl3. The relevant data of the obtained product are as follows:

[0077] The yield of the anti-Markovnikov hydroamination product was 72%, r = 96:4.

[0078] 1 H NMR(400MHz,Chloroform-d)δ7.27–7.06(m,5H),6.98(dd,J=8.9,7.4Hz,1H),6.45(d,J=7.4Hz, 1H), 6.32–6.34 (m, 2H), 3.51 (s, 1H), 3.29 (t, J = 7.0Hz, 2H), 2.81 (t, J = 7.0Hz, 2H), 2.18 (s, 3H).

[0079] 13 C NMR (101MHz, Chloroform-d) δ147.04,138.34,137.98,128.11,127.74,127.55,125.35,117.38,112.75,109.12,44.03,34.54,20.59.

[0080] Example 2.6

[0081] The catalytic reaction proceeds through the following process:

[0082] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by 4-methylaniline (0.0268g, 0.25mmol) and styrene (0.1302g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 21 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after dissolving with CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after dissolving with CDCl3. The relevant data of the obtained product are as follows:

[0083] The yield of the anti-Markovnikov hydroamination product was 83%, r=96:4.

[0084] 1 H NMR(400MHz,Chloroform-d)δ7.27–7.09(m,5H),6.90(d,J=8.1Hz,2H),6.54–6.40( m,2H),3.54–3.34(m,1H),3.29(t,J=7.0Hz,2H),2.81(t,J=7.0Hz,2H),2.15(s,3H).

[0085] 13 C NMR (101MHz, Chloroform-d) δ144.71,138.38,128.73,127.75,127.53,125.64,125.33,112.19,44.39,34.51,19.35.

[0086] Example 2.7

[0087] The catalytic reaction proceeds through the following process:

[0088] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by 4-fluoroaniline (0.0278g, 0.25mmol) and styrene (0.1302g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 21 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after dissolving with CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after dissolving with CDCl3. The relevant data of the obtained product are as follows:

[0089] The yield of the anti-Markovnikov hydroamination product was 78%, r=90:10.

[0090] 1 H NMR (400MHz, Chloroform-d) δ7.28–7.09(m,5H),6.80(t,J=8.7Hz,2H),6.54–6.36(m,2H),3.45(s,1H),3.27(t,J=7.0Hz,2H),2.81(t,J=6.9Hz,2H).

[0091] 13 C NMR(101MHz,Chloroform-d)δ156.01,153.67,143.35,143.33,138.16,127.67( d,J=13.2Hz),125.45,114.65(d,J=22.2Hz),112.79(d,J=7.4Hz),44.65,34.44.

[0092] 19 F NMR(376MHz,Chloroform-d)δ-127.98.

[0093] Example 2.8

[0094] The catalytic reaction proceeds through the following process:

[0095] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by 4-bromoaniline (0.0430g, 0.25mmol) and styrene (0.1302g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 21 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after being dissolved in CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after being dissolved in CDCl3. The relevant data of the obtained product are as follows:

[0096] The yield of the anti-Markovnikov hydroamination product was 81%, r=92:8.

[0097] 1 H NMR (400MHz, Chloroform-d) δ7.27–7.04(m,7H),6.43–6.29(m,2H),3.58(s,1H),3.25(t,J=7.0Hz,2H),2.79(t,J=7.0Hz,2H).

[0098] 13 C NMR (101MHz, Chloroform-d) δ145.95,137.98,130.91,127.71,127.62,125.49,113.48,107.91,43.93,34.26.

[0099] Example 2.9

[0100] The catalytic reaction proceeds through the following process:

[0101] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by 4-tert-butylaniline (0.0373g, 0.25mmol) and styrene (0.1302g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 21 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after dissolving with CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after dissolving with CDCl3. The relevant data of the obtained product are as follows:

[0102] The yield of the anti-Markovnikov hydroamination product was 74%, r=74:0.

[0103] 1 H NMR (400MHz, Chloroform-d) δ7.27–7.10(m,7H),6.57–6.43(m,2H),3.49(s,1H),3.32(t,J=7.0Hz,2H),2.84(t,J=7.0Hz,2H),1.21(s,9H).

[0104] 13 C NMR (101MHz, Chloroform-d) δ144.67,139.26,138.41,127.76,127.55,125.35,125.01,111.72,44.30,34.68,32.83,30.53.

[0105] Example 2.10

[0106] The catalytic reaction proceeds through the following process:

[0107] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by aniline (0.0233g, 0.25mmol) and 2-methylstyrene (0.1477g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 21 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after dissolving with CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after dissolving with CDCl3. The relevant data of the obtained product are as follows:

[0108] The yield of the anti-Markovnikov hydroamination product was 88%, r=90:10.

[0109] 1 H NMR(400MHz,Chloroform-d)δ7.14–7.06(m,6H),6.63(t,J=7.3Hz,1H),6.54(d,J= 7.9Hz,2H),3.61(s,1H),3.29(t,J=7.3Hz,2H),2.84(t,J=7.3Hz,2H),2.26(s,3H).

[0110] 13C NMR (101MHz, Chloroform-d) δ147.04,136.39,135.29,129.41,128.27,128.24,125.52,125.09,116.42,111.90,42.85,31.93,18.37.

[0111] Example 2.11

[0112] The catalytic reaction proceeds through the following process:

[0113] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by aniline (0.0233g, 0.25mmol) and 2-fluorostyrene (0.1527g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 21 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after dissolving with CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after dissolving with CDCl3. The relevant data of the obtained product are as follows:

[0114] The yield of the anti-Markovnikov hydroamination product was 87%, r=92:8.

[0115] 1 H NMR (400MHz, Chloroform-d) δ7.22–6.89(m,6H),6.67–6.59(m,1H),6.58–6.52(m,2H),3.65(s,1H),3.33(t,J=7.1Hz,2H),2.88(t,J=7.1Hz,2H).

[0116] 13 C NMR(101MHz,Chloroform-d)δ161.55,146.89,130.04(d,J=5.0Hz),128.27,127.17(d,J=8.1Hz), 125.23(d,J=16.1Hz),123.11(d,J=3.6Hz),116.45,114.38(d,J=22.2Hz),111.88,42.86,28.17.

[0117] 19 F NMR(376MHz,Chloroform-d)δ-118.42.

[0118] Example 2.12

[0119] The catalytic reaction proceeds through the following process:

[0120] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by aniline (0.0233g, 0.25mmol) and 3-methylstyrene (0.1477g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 24 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after being dissolved in CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after being dissolved in CDCl3. The relevant data of the obtained product are as follows:

[0121] The yield of the anti-Markovnikov hydroamination product was 86%, r=93:7.

[0122] 1 H NMR (400MHz, Chloroform-d) δ7.20–6.86(m,6H),6.67–6.47(m,3H),3.56(s,1H),3.29(t,J=7.0Hz,2H),2.78(t,J=7.0Hz,2H),2.25(s,3H).

[0123] 13 C NMR (101MHz, Chloroform-d) δ147.05,138.20,137.16,128.53,128.23,127.45,126.14,124.76,116.40,111.98,44.02,34.44,20.35.

[0124] Example 2.13

[0125] The catalytic reaction proceeds through the following process:

[0126] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by aniline (0.0233g, 0.25mmol) and 3-fluorostyrene (0.1527g, 1.25mmol), and then 1mL of Dioxane. After the addition was completed, the reaction bottle was reacted at 90°C for 4 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after being dissolved in CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after being dissolved in CDCl3. The relevant data of the obtained product are as follows:

[0127] The yield of the anti-Markovnikov hydroamination product was 70%, r=71:29.

[0128] 1 H NMR (400MHz, Chloroform-d) δ7.27–6.49(m,9H),3.57(s,1H),3.33(t,J=7.0Hz,2H),2.83(t,J=7.0Hz,2H).

[0129] 13 C NMR(101MHz,Chloroform-d)δ163.22,146.79,140.89(d,J=7.3Hz),128.99(d,J=8.3Hz),128.31, 123.40(d,J=2.9Hz),116.62,114.60(d,J=20.9Hz),112.31(d,J=21.0Hz),111.98,43.76,34.28.

[0130] 19 F NMR(376MHz,Chloroform-d)δ-113.25.

[0131] Example 2.14

[0132] The catalytic reaction proceeds through the following process:

[0133] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by aniline (0.0233g, 0.25mmol) and 4-methylstyrene (0.1477g, 1.25mmol), and then 1mL of Dioxane. After the addition was completed, the reaction bottle was reacted at 90°C for 18 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after dissolving with CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after dissolving with CDCl3. The relevant data of the obtained product are as follows:

[0134] The yield of the anti-Markovnikov hydroamination product was 95%, r=95:0.

[0135] 1 H NMR (400MHz, Chloroform-d) δ7.15–6.87(m,6H),6.70–6.44(m,3H),3.55(s,1H),3.27(t,J=7.0Hz,2H),2.77(t,J=7.0Hz,2H),2.24(s,3H).

[0136] 13 C NMR (101MHz, Chloroform-d) δ147.06,135.15,134.92,128.26,128.24,127.64,116.41,111.98,44.10,34.05,19.99.

[0137] Example 2.15

[0138] The catalytic reaction proceeds through the following process:

[0139] Under the protection of inert gas, add [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) to a 10mL reaction bottle, then add aniline (0.0233g, 0.25mmol) and 4-fluorostyrene (0.1527g, 1.25mmol), and then add 1mL of Dioxane. After the addition is completed, the reaction bottle is reacted at 90°C for 48 hours. After the reaction is completed, the solvent is removed in vacuo, toluene (internal standard) is added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r are quantitatively analyzed by nuclear magnetic hydrogen spectrum after dissolving with CDCl3. After obtaining the results, the target product is separated and purified by column chromatography, and the target product is characterized by nuclear magnetic resonance after dissolving with CDCl3. The relevant data of the obtained product are as follows:

[0140] The yield of the anti-Markovnikov hydroamination product was 36%, r=36:0.

[0141] 1 H NMR (400MHz, Chloroform-d) δ7.20–6.83(m,6H),6.68–6.43(m,3H),3.54(s,1H),3.29(t,J=7.0Hz,2H),2.79(t,J=7.0Hz,2H).

[0142] 13 C NMR(101MHz,Chloroform-d)δ161.83,159.40,146.87,133.93(d,J=3.2Hz),1 29.17,129.09,128.29,116.56,114.34(d,J=21.2Hz),111.97,44.07,33.68.

[0143] 19 F NMR(376MHz,Chloroform-d)δ-116.74.

[0144] Example 2.16

[0145] The catalytic reaction proceeds through the following process:

[0146] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by aniline (0.0233g, 0.25mmol) and 4-methoxystyrene (0.1677g, 1.25mmol), and then 1mL of Dioxane. After the addition was completed, the reaction bottle was reacted at 90°C for 34 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after being dissolved in CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after being dissolved in CDCl3. The relevant data of the obtained product are as follows:

[0147] The yield of the anti-Markovnikov hydroamination product was 93%, r=94:6.

[0148] 1H NMR (400MHz, Chloroform-d) δ7.33–7.00(m,6H),6.70–6.46(m,3H),3.61(s,1H),3.32(t,J=7.0Hz,2H),2.82(t,J=7.0Hz,2H),1.25(s,9H).

[0149] 13 C NMR (101MHz, Chloroform-d) δ148.26,147.08,135.17,128.24,127.42,124.47,116.40,111.98,44.01,33.97,33.40,30.37.

[0150] Example 2.17

[0151] The catalytic reaction proceeds through the following process:

[0152] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by aniline (0.0233g, 0.25mmol) and 2-vinylpyridine (0.1314g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 21 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after dissolving with CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after dissolving with CDCl3. The relevant data of the obtained product are as follows:

[0153] The yield of the anti-Markovnikov hydroamination product was 49%, r=49:0.

[0154] 1 H NMR (400MHz, Chloroform-d) δ8.46(d,J=4.9Hz,1H),7.58–6.39(m,8H),3.91(s,1H),3.44(t,J=6.6Hz,2H),2.99(t,J=6.6Hz,2H).

[0155] 13 C NMR (101MHz, Chloroform-d) δ158.78,148.35,147.17,135.45,128.19,122.28,120.42,116.26,111.91,42.51,36.45.

[0156] Example 2.18

[0157] The catalytic reaction proceeds through the following process:

[0158] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by aniline (0.0233g, 0.25mmol) and 2-vinylthiophene (0.1377g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 21 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydrogen amination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after being dissolved in CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after being dissolved in CDCl3. The relevant data of the obtained product are as follows:

[0159] The yield of the anti-Markovnikov hydroamination product was 79%, r=87:13.

[0160] 1 H NMR (400MHz, Chloroform-d) δ7.21–6.40(m,8H),3.68(s,1H),3.35(t,J=6.8Hz,2H),3.04(t,J=6.8Hz,2H).

[0161] 13 C NMR (101MHz, Chloroform-d) δ146.73,140.73,128.28,125.94,124.25,122.83,116.62,112.05,44.19,28.72.

[0162] Example 2.19

[0163] The catalytic reaction proceeds through the following process:

[0164] Under the protection of inert gas, [Al] catalyst (0.0107g, 10mmol%) and potassium tert-butoxide (0.0561g, 2equiv.) were added to a 10mL reaction bottle, followed by aniline (0.0233g, 0.25mmol) and 1,1-diphenylethylene (0.2253g, 1.25mmol), and then 0.5mL of THF and Dioxane were added. After the addition was completed, the reaction bottle was reacted at 60°C for 24 hours. After the reaction was completed, the solvent was removed in vacuo, toluene (internal standard) was added, and the yield of the anti-Markovnikov hydroamination product and the ratio of the main and by-products r were quantitatively analyzed by nuclear magnetic hydrogen spectrum after being dissolved in CDCl3. After obtaining the results, the target product was separated and purified by column chromatography, and nuclear magnetic characterization was performed after being dissolved in CDCl3. The relevant data of the obtained product are as follows:

[0165] The yield of the anti-Markovnikov hydroamination product was 63%, r=63:0.

[0166] 1 H NMR (400MHz, Chloroform-d) δ7.29–7.05(m,12H),6.64(t,J=7.3Hz,1H),6.52(d,J=7.9Hz,2H),4.22(t,J=7.6Hz,1H),3.67(d,J=7.7Hz,2H),3.56(s,1H).

[0167] 13 C NMR (101MHz, Chloroform-d) δ146.81,141.27,128.27,127.71,127.14,125.77,116.65,112.15,49.27,47.54.

[0168] The above embodiments are only preferred implementations of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A method for the anti-Markovnikov hydroamination of aromatic olefins catalyzed by aluminum, characterized in that: The following steps are involved: In an inert gas, the catalyst [Al] and additives are dissolved in an organic solvent, and then olefin is added. and amine compounds After the temperature rise reaction is completed, a reaction mixture is obtained, and the target product is obtained by post-treatment and purification. Among them, Ar 1 ,Ar 2 is an aryl group or a heteroaryl group.

2. The method for the anti-Markovnikov hydroamination of aromatic olefins catalyzed by aluminum according to claim 1, characterized in that: The catalyst [Al] in 1 is a compound having the following structural formula:

3. The method for preparing the catalyst according to claim 2, characterized in that: It includes: Under an inert atmosphere, an organic solution of β-diketoimines ligand LH and trimethylaluminum is reacted in an organic solvent at 0°C, and then the reaction mixture is reacted at room temperature to obtain a turbid liquid of an aluminum methyl compound stabilized with a β-diketoimines ligand. The aluminum methyl compound stabilized with a β-diketoimines ligand is filtered out of the system, washed with an organic solvent, and vacuum dried to obtain a white solid. Among them, the structural formula of β-diketimine ligand LH is:

4. The preparation method according to claim 3, characterized in that: The reaction process is always under an inert atmosphere.

5. The preparation method according to claim 3, characterized in that: It should be first carried out at 0°C for 0.5 hours and then at room temperature for 18 hours.

6. The preparation method according to claim 3, characterized in that: The molar ratio of the β-diketoimine ligand LH to the trimethylaluminum organic solution is 1:1.2 to 1:3, and the concentration of trimethylaluminum in the trimethylaluminum organic solution is 1 mol / L.

7. The preparation method according to claim 3, characterized in that: The organic solvents are all selected from n-hexane.

8. The preparation method according to claim 3, characterized in that: The ratio of the amount of the substance containing the β-diketimine ligand LH to the volume of the organic solvent is 0.5 mmol / mL.

9. The method for the anti-Markovnikov hydroamination of aromatic olefins catalyzed by aluminum according to claim 1, characterized in that: The additive is one of potassium tert-butoxide, sodium tert-butoxide, cesium carbonate, sodium amide, sodium hydroxide, sodium methoxide, and triethylamine; and the molar ratio of the amine compound to the additive is 1:

2.

10. The method for the anti-Markovnikov hydroamination of aromatic olefins catalyzed by aluminum according to claim 1, characterized in that: The organic solvent is one or two of 1,4-dioxane, tetrahydrofuran, tert-butyl methyl ether, chlorobenzene, and dimethyl sulfoxide; the ratio of the amount of the amine compound to the volume of the organic solvent is 0.25-0.5 mmol / mL.

11. The method for the anti-Markovnikov hydroamination of aromatic olefins catalyzed by aluminum according to claim 1, characterized in that: The molar ratio of the amine compound to the olefin is 1:2 to 1:

5.

12. The method for the anti-Markovnikov hydroamination of aromatic olefins catalyzed by aluminum according to claim 1, characterized in that: The molar amount of the catalyst [Al] is 1 to 15% of the molar amount of the amine compound.

13. The method for the anti-Markovnikov hydroamination of aromatic olefins catalyzed by aluminum according to claim 1, characterized in that: The temperature-raising reaction conditions are as follows: the reaction is carried out under magnetic stirring, the temperature is 60° C. or 90° C., and the reaction time is 4 to 48 hours.

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