A pillar aromatic binaphthol chiral catalyst and its preparation method and application

Abstract

The present invention provides a pillararene binaphthol chiral catalyst, its preparation method, and application. The present invention provides a pillararene binaphthol chiral catalyst having the chemical formula shown below, as well as a method for preparing the pillararene binaphthol chiral catalyst. The present method features mild reaction conditions, simple operation, low cost, environmental friendliness, and high yield. The provided pillararene binaphthol chiral catalyst can be used in asymmetric organic catalysis and has broad application prospects in the field of chiral catalysis. #imgabs0#

Description

Technical Field

[0001] The present invention belongs to the technical field of chiral catalysts, and relates to a pillar[5]arene-modified axial chiral binaphthol chiral catalyst, a preparation method and an application thereof, and specifically relates to a pillar[5]arene-modified axial chiral binaphthol chiral phosphoric acid catalyst, a preparation method and an application thereof. Background Art

[0002] Chirality is a property that is ubiquitous in nature and is widely involved in the fields of molecules, atoms, supramolecular molecules, etc. Molecules of different chirality often exhibit different chemical and biological toxicological activities, so the demand for the preparation of highly optically pure chiral compounds of a single configuration is increasing. At present, catalytic asymmetric synthesis is still one of the most direct and effective ways to obtain chiral compounds of a single configuration. In recent decades, chemists have devoted themselves to and synthesized a variety of chiral catalysts with excellent performance, and have successfully applied them to various asymmetric catalytic reactions. However, the catalytic performance of chiral catalysts is affected by the substrate structure, reaction conditions, etc., and there are still many asymmetric reactions that lack effective catalysts. Therefore, the design and search for new chiral catalysts with high activity and high selectivity has always been the focus of the field of asymmetric catalysis.

[0003] Pillarene, as a novel macrocyclic host, can complex neutral or positively charged organic molecules of varying structures in low-polarity organic solvents by varying the size of its cavities. Therefore, it is well-suited for constructing supramolecular catalysts with broad applicability in organic systems. Furthermore, for certain catalytic reactions, the absence of supramolecular host-guest complexation significantly reduces reaction rates and enantioselectivity, highlighting the importance of this type of supramolecular chiral catalysis.

[0004] Therefore, how to use a simple method to develop a new, efficient, substrate-adaptable, and applicable to various types of reactions of pillar aromatic hydrocarbon-modified binaphthol supramolecular chiral catalyst is an urgent task to be solved. Summary of the Invention

[0005] The first object of the present invention is to provide a pillararene binaphthol chiral catalyst in view of the deficiencies in the prior art.

[0006] A pillararene binaphthol chiral catalyst, the chemical structure of which is shown below:

[0007]

[0008] The second object of the present invention is to provide a method for preparing the above-mentioned pillararene binaphthol chiral catalyst, which has mild reaction conditions, simple operation, low cost, no pollution to the environment and can achieve high yield.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] A method for preparing a pillararene binaphthol chiral catalyst specifically comprises the following steps:

[0011] Step (1), dissolving (R)-(+)-1,1'-binaphthol in tetrahydrofuran (THF), and then reacting with sodium hydride (NaH) and bromomethyl methyl ether (MOMBr) to obtain compound 1;

[0012] Step (2), dissolving compound 1 in tetrahydrofuran (THF), and then reacting with n-butyllithium (n-BuLi) in n-hexane and iodine to obtain compound 2;

[0013] Step (3), compound 2, 1,4-phenylenediboronic acid bis(pinacol) ester, palladium catalyst, and base are mixed, and then toluene PhCH3, anhydrous ethanol and water are added to react to obtain compound 3;

[0014] Step (4), mixing phenylene dimethyl ether, paraformaldehyde (CH2O)n and 1,2-dichloroethane DCE, and then adding boron trifluoride ether complex BF3·(C2H5)2O to react to obtain compound 4;

[0015] Step (5), dissolving compound 4 in dichloromethane (DCM), and then adding boron tribromide (BBr3) to react to obtain compound 5;

[0016] Step (6), dissolving compound 5 in dichloromethane (DCM), then adding pyridine (Py) and trifluoromethanesulfonic anhydride (Tf2O) to react to obtain compound 6;

[0017] Step (7), mixing compound 3, compound 6, a palladium catalyst, a ligand and a base and dissolving them in a mixed solvent of 1,4-dioxane and deionized water to react to obtain compound 7;

[0018] Step (8), dissolving compound 7 in dichloromethane (DCM), then adding trifluoroacetic acid (TFA) to react to obtain compound 8;

[0019] Step (9), dissolving compound 8 in a mixed solvent of pyridine and water, and then adding phosphorus oxychloride POCl3 to react to obtain compound 9, i.e., the pillararene binaphthol chiral catalyst;

[0020] The synthetic route of the reaction is as follows:

[0021]

[0022]

[0023] Preferably, the palladium catalyst in step (3) is tetrakis(triphenylphosphine)palladium Pd(PPh3)4, and the base is anhydrous sodium carbonate Na2CO3.

[0024] Preferably, the molar ratio of compound 3, compound 6, palladium catalyst, ligand and base in step (7) is (1-1.2):3:0.1:0.25:2.5.

[0025] Preferably, the palladium catalyst in step (7) is tetrakis(triphenylphosphine)palladium Pd(PPh3)4, the ligand is triphenylphosphine, and the base is potassium phosphate.

[0026] Preferably, the volume ratio of 1,4-dioxane to deionized water in the mixed solvent of step (7) is (4-5):1.

[0027] Preferably, the mass volume ratio of compound 7 and trifluoroacetic acid TFA in step (8) is 200 mg: (0.1-0.2) mL.

[0028] Preferably, the mass volume ratio of compound 8 and phosphorus oxychloride POCl3 in step (9) is 150 mg: (0.2-0.3) mL.

[0029] The third object of the present invention is to provide the use of the above-mentioned pillararene binaphthol chiral catalyst in asymmetric organic catalysis.

[0030] Preferably, the asymmetric organic catalysis includes but is not limited to the preparation of asymmetric 2,3-dihydroquinazolin-4-(1H)ones and the like.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The present invention provides a method for preparing a pillararomatic binaphthol chiral catalyst with mild reaction conditions, simple operation, low cost, no pollution to the environment, and high yield. The prepared pillararomatic binaphthol chiral catalyst has a novel structure and can be applied to asymmetric organic catalysis, thus having broad application prospects in the field of chiral catalysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is the H NMR spectrum of compound 3;

[0034] Figure 2 is the carbon NMR spectrum of compound 3;

[0035] Figure 3 is the ESI-MS spectrum of compound 3;

[0036] Figure 4 is the H NMR spectrum of compound 7;

[0037] Figure 5 is the carbon NMR spectrum of compound 7;

[0038] Figure 6is the ESI-MS spectrum of compound 7;

[0039] Figure 7 is the H NMR spectrum of compound 8;

[0040] Figure 8 is the carbon NMR spectrum of compound 8;

[0041] Figure 9 is the ESI-MS spectrum of compound 8;

[0042] Figure 10 is the H NMR spectrum of compound 9;

[0043] Figure 11 is the nuclear magnetic resonance phosphorus spectrum of compound 9;

[0044] Figure 12 This is the high-resolution mass spectrum of compound 9;

[0045] Figure 13 is the carbon NMR spectrum of compound 9. DETAILED DESCRIPTION

[0046] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0047] Example 1: Synthesis of Compound 1

[0048]

[0049] (R)-(+)-1,1'-binaphthol (3 g, 10.48 mmol) was added to a dry 100 mL three-necked flask. The atmosphere was replaced with nitrogen three times. Redistilled tetrahydrofuran (60 mL) was added under a nitrogen atmosphere and stirred until dissolved. Sodium hydride (1.26 g, 31.43 mmol) was slowly added at 0°C and the mixture was allowed to react at low temperature for 1 hour. The reaction flask was then allowed to react at room temperature for 15 minutes. Bromomethyl methyl ether (5.24 g, 41.91 mmol) was then slowly added at 0°C and allowed to react at room temperature for 2.5 hours. Upon completion of the reaction, the mixture was quenched with saturated ammonium chloride in an ice bath. The mixture was extracted with ethyl acetate several times, dried over anhydrous sodium sulfate, and the solvent removed under reduced pressure. The product was purified by column chromatography (PE / EA = 5:1, v / v) to obtain the product, Compound 1 (3.5 g, yield: 90%).

[0050] Compound 1, white solid, 1H NMR(500MHz,Chloroform-d)δ7.95(d,J=9.0Hz,2H),7.87(d,J=8.2Hz,2H),7.58(d,J=9.0Hz,2H),7.34 (m,2H),7.22(m,2H),7.15(d,J=8.5Hz,2H),5.08(d,J=6.8Hz,2H),4.98(d,J=6.8Hz,2H),3.14(s,6H).

[0051] Example 2: Synthesis of Compound 2

[0052]

[0053] Compound 1 (0.5 g, 1.34 mmol) was added to a dry 50 mL three-necked flask. The atmosphere was replaced with nitrogen three times. Redistilled tetrahydrofuran (25 mL) was added under a nitrogen atmosphere at –78°C and stirred until dissolved. A 2.5 M solution of n-butyllithium in n-hexane (1.6 mL) was then slowly added dropwise. After the addition was complete, the reaction was maintained at 0°C for 2 h. The reaction flask was then placed at –78°C and iodine (1.36 g, 5.34 mmol) was added. After the addition was complete, the reaction was maintained at 0°C for 2 h. Upon completion of the reaction, the reaction was quenched with saturated sodium thiosulfate aqueous solution, extracted with ethyl acetate several times, and the solvent was removed in vacuo. The product, compound 2 (0.6 g, yield: 73%), was obtained by column chromatography (PE / EA = 30:1, v / v).

[0054] Compound 2, white solid, 1 H NMR(500MHz,Chloroform-d)δ8.54(s,2H),7.78(d,J=8.2Hz,2H),7.42(m,2H),7.30(m ,2H),7.17(d,J=8.5Hz,2H),4.81(d,J=5.7Hz,2H),4.69(d,J=5.7Hz,2H),2.60(s,6H).

[0055] Example 3: Synthesis of Compound 3

[0056]

[0057] The above-synthesized compound 2 (225 mg, 0.36 mmol), 1,4-phenylenediboronic acid bis(pinacol) ester (594 mg, 1.8 mmol), tetrakis(triphenylphosphine)palladium (41.6 mg, 0.036 mmol), and anhydrous sodium carbonate (382 mg, 3.6 mmol) were added to a 50 mL dry Shrek reaction bottle and replaced with nitrogen three times. In a nitrogen atmosphere, ultra-dry toluene (8 mL), anhydrous ethanol (4 mL), and deionized water (2 mL) were injected into it. Nitrogen was used to bubble deoxygenate for about 30 minutes. After the reaction, the reaction was placed in an oil bath and heated to 92°C for 24 hours. Spot sampling was performed to monitor the reaction. After the reaction was completed, the solid in the reaction solution was filtered, concentrated in vacuo, and rapidly separated by column chromatography (PE / EA=5:1, ν / ν) to obtain compound 3 (154 mg, yield: 55%). Its nuclear magnetic resonance hydrogen spectrum (500 MHz, CDCl3, 25°C) is as follows Figure 1 As shown; NMR carbon spectrum (125MHz, CDCl3, 25℃) Figure 2 As shown; ESI-MS spectrum as Figure 3 As shown, ESI-TOF-MS (m / z) [3+Na] + calcd for C 48 H 52 B2O8Na + ,801.3756; found,801.3783,error:3.4ppm.

[0058] Compound 3, yellow solid, 1 H NMR(500MHz,Chloroform-d)δ7.96–7.88(m,8H),7.79(t,J=9.3Hz,4H),7.41(m,2H),7.28 (d,J=3.6Hz,4H),4.41(d,J=5.9Hz,2H),4.38(d,J=5.9Hz,2H),2.33(s,6H),1.38(s,24H). 13 C NMR(125MHz,Chloroform-d)δ151.3,141.9,135.3,134.8,133.7,130.8,130.7,128.9 ,127.9,126.5,126.4,126.4,125.2,98.5,83.8,55.9,24.9.ESI-TOF-MS(m / z):[M+Na] + calcd for C 48 H 52 B2O8Na + ,801.3756; found,801.3783,error:3.4ppm.

[0059] Example 4: Synthesis of Compound 4

[0060]

[0061] Add p-phenylenedimethyl ether (13.8 g, 10 mmol), paraformaldehyde (9.0 g, 30 mmol), and 1,2-dichloroethane (250 mL) to a dry 500 mL round-bottom flask. Stir the mixture at room temperature for 30 min. Then, slowly add boron trifluoride etherate (12.6 mL, 10 mmol) and observe the color change. After the reaction is complete, quench with water, extract with dichloromethane several times, dry, concentrate, and filter through a column chromatography (DCM / PE = 20:1, v / v) to obtain the product, compound 4 (11.5 g, yield: 77%).

[0062] Compound 4, white solid, 1 HNMR(500MHz,Chloroform-d)δ6.79(s,10H),3.77(s,10H),3.67(s,30H).

[0063] Example 5: Synthesis of Compound 5

[0064]

[0065] Compound 4 (2.0 g, 2.68 mmol) and redistilled dichloromethane (80 mL) were added to a dry 250 mL round-bottom flask and the atmosphere was replaced with nitrogen three times. Boron tribromide (0.23 mL, 2.41 mmol) was then slowly added dropwise in an ice-water bath. A microplate was used to track the reaction at room temperature. After completion of the reaction, the product was quenched with water, extracted with dichloromethane several times, and then concentrated under vacuum to remove the solvent. Recrystallization was performed by adding methanol. The resulting product was filtered, dried, and purified by column chromatography (PE / EA = 5:1, v / v) to afford compound 5 (0.6 g, 30% yield).

[0066] Example 6: Synthesis of Compound 6

[0067]

[0068] Compound 5 (1.00 g, 1.36 mmol) was placed in a dry 100 mL three-necked flask and the atmosphere was replaced with nitrogen three times. Under a nitrogen atmosphere, the reaction flask was placed in a constant-temperature ice-water bath. Redistilled dichloromethane (50 mL) and ultra-dry pyridine (5 mL) were added, and trifluoromethanesulfonic anhydride (6.5 g, 22.64 mmol) was slowly added dropwise to the mixture. The reaction was allowed to proceed at room temperature for 12 h. After completion of the reaction, the mixture was extracted with dichloromethane several times, concentrated under vacuum to remove the solvent, and purified by column chromatography (PE / DCM = 15:1, v / v) to obtain the product, compound 6 (1.0 g, yield: 84%).

[0069] Compound 6, light red solid, 1 HNMR(500MHz,Chloroform-d)δ7.13(s,1H),6.85(s,1H),6.81–6.75(m,6H),6.73(d,J=3.2Hz,2H),3.84(s,2H),3.80–3.75(m,8H),3.71–3.62(m,27H).

[0070] Example 7: Synthesis of Compound 7

[0071]

[0072] Compound 3 (156 mg, 0.2 mmol), compound 6 (521 mg, 0.6 mmol), tetrakis(triphenylphosphine)palladium (23.1 mg, 0.02 mmol), triphenylphosphine (13.1 mg, 0.05 mmol) and potassium phosphate (106.1 mg, 0.5 mmol) were placed in a 25 mL dry Shrek tube and replaced with nitrogen three times. Under a nitrogen atmosphere, 1,4-dioxane (4 mL) and deionized water (1 mL) were added to the reaction tube. Nitrogen was then used to bubble deoxygenate for 30 minutes, and then the reaction tube was placed at 108 ° C for 24 hours. After the reaction was completed, the solvent was removed in vacuo, extracted with dichloromethane, concentrated in vacuo, and separated by column chromatography (PE / EA=2:1, ν / ν) to obtain compound 7 (138 mg, yield: 35%). Its nuclear magnetic resonance hydrogen spectrum (500 MHz, CDCl3, 25 ° C) is as follows Figure 4 As shown; NMR carbon spectrum (125MHz, CDCl3, 25℃) Figure 5 As shown; ESI-MS spectrum as Figure 6 As shown, ESI-TOF-MS (m / z) [7+Na] + calcd for C 124 H 122 O 22 Na +,1986.8354; found,1986.8359, error: 0.3 ppm. [7+K] + Calculated for C 124 H 122 O 22 K + ,2002.8093; found,2002.8098, error: 0.3 ppm.

[0073] Compound 7, white solid, 1 H NMR(500 MHz, Chloroform-d) δ 8.02(s, 2H), 7.94(d, J = 8.0 Hz, 2H), 7.83–7.78(m, 4H), 7.46(m, 2H), 7.38–7.31(m, 8H), 7.19(s, 2H), 6.83–6.80(m, 6H), 6.77(d, J = 6.0 Hz, 6H), 6.69(d, J = 12.4 Hz, 4H), 6.02(s, 2H), 4.50(d, J = 5.9 Hz, 2H), 4.47(d, J = 5.8 Hz, 2H), 3.92(s, 4H), 3.81(d, J = 4.0 Hz, 12H), 3.73(s, 4H), 3.67(t, J = 1.9 Hz, 2--4H), 3.64–3.56(m, 25H), 3.40(s, 5H), 2.41(s, 6H). 13 C NMR(125 MHz, Chloroform-d) δ 151.5, 151.3, 150.9, 150.9, 150.3, 141.6, 135.3, 133.6, 132.8, 130.9, 130.5, 129.9, 129.6, 129.2, 128.6, 128.4, 128.4, 128.3, 128.3, 127.9, 127.2, 126.6, 126.4, 126.3, 125.3, 114.7, 114.6, 114.4, 114.3, 114.1, 114.0, 113.7, 113.5, 112.5, 98.6, 56.0, 55.9, 55.8, 55.7, 55.7, 55.6, 54.9, 32.3, 30.7, 30.2, 29.8, 29.6. ESI-TOF-MS(m / z): [M+Na] + Calculated for C 124 H 122 O 22 Na<000——031>,1986.8354; found,1986.8359, error: 0.3 ppm. [M+K] + It should be noted that there seems to be an error in the number of "2--4H" in the original text's NMR data, which is likely a typo. Here it is translated as "2--4H" as it is, but it might need to be corrected in the original source for accurate interpretation.calcd for C 124 H 122 O 22 K + ,2002.8093; found,2002.8098,error:0.3ppm.

[0074] Example 8: Synthesis of Compound 8

[0075]

[0076] Compound 7 (200 mg, 0.197 mmol) was placed in a 50 mL dry three-necked flask and replaced with nitrogen three times. Under a nitrogen atmosphere, redistilled dichloromethane (20 mL) was added to the reaction flask and stirred until completely dissolved. Trifluoroacetic acid (0.1 mL) was then slowly added dropwise. The reaction was tracked by spot plate. After the reaction was completed, vacuum concentration was performed, column chromatography separation (PE / EA=2:1, ν / ν), and compound 8 (172 mg, yield: 90%) was obtained after vacuum drying. Its nuclear magnetic resonance hydrogen spectrum (500 MHz, CDCl3, 25 ° C) is as follows Figure 7 As shown; NMR carbon spectrum (125MHz, CDCl3, 25℃) Figure 8 As shown; ESI-MS spectrum as Figure 9 As shown, ESI-TOF-MS (m / z) [8+Na] + calcd for C 120 H 114 O 20 Na + ,1898.783; found,1898.7813,error:-0.9ppm.

[0077] Compound 8, white solid, 1 H NMR (500MHz, Chloroform-d) δ8.10 (s, 2H), 7.98 (d, J = 8.0 Hz, 2H), 7.73 (d, J = 8. 2Hz,4H),7.46–7.41(m,2H),7.38–7.35(m,2H),7.29(d,J=8.2Hz,5H),7.12(s, 2H),6.88(s,2H),6.82–6.64(m,14H),5.92(s,2H),5.56(s,2H),5.35(d,J=1.6 Hz, 2H), 3.93 (s, 4H), 3.80 (d, J = 5.0Hz, 12H), 3.71–3.54 (m, 52H), 3.39 (s, 6H). 13C NMR(125MHz,Chloroform-d)δ155.4,150.2,149.9,149.9,149.7,149.6,149.4,149.3,141.1, 136.9,132.0,131.6,130.3,129.9,129.0,128.5,128.2,127.5,127.4,127.4,127.3,127.3,1 27.0,126.9,126.4,123.4,123.2,113.5,113.4,113.3,113.0,112.9,112.8,112.6,111.7,54 .9,54.9,54.8,54.8,54.7,54.7,54.0,31.8,29.1,28.9,28.7,28.6.ESI-TOF-MS(m / z):[M+Na] + calcd for C 120 H 114 O 20 Na + ,1898.783; found,1898.7813,error:–0.9ppm.

[0078] Example 9: Synthesis of Pillarene Binaphthol Chiral Catalyst

[0079]

[0080] Compound 8 (150 mg, 0.08 mmol) was placed in a dry 50 mL three-necked flask and replaced with nitrogen three times. Under a nitrogen atmosphere, ultra-dry pyridine (10 mL) was added thereto until completely dissolved. Phosphorus oxychloride (0.2 mL) was then slowly added dropwise thereto, and the reaction system was stirred at room temperature for 10 min. The reaction flask was then placed in a 90 ° C oil bath to react for 2 h. The reaction was cooled to room temperature, and deionized water (10 mL) was added thereto to react for 10 min. The reaction flask was then placed back in a 90 ° C oil bath to react for 2 h. After the reaction was completed, it was extracted with dichloromethane, the organic phase was concentrated and collected, and then washed with dilute hydrochloric acid aqueous solution to pH = 6. The resulting solution was vacuum-desolventized and recrystallized with n-hexane. The solid was collected by filtration and vacuum-dried to obtain compound 9, i.e., the columnar aromatic binaphthol chiral catalyst (116 mg, yield: 75%). Its nuclear magnetic resonance hydrogen spectrum (500 MHz, CDCl3, 25 ° C) is as follows Figure 10 Its nuclear magnetic resonance phosphorus spectrum (202MHz, CDCl3, 25℃) is as shown in Figure 11 As shown, according to the nuclear magnetic phosphorus spectrum, there is a single peak at 2.83ppm, indicating the successful preparation of (R)-3.4; the high-resolution mass spectrum is shown in Figure 12As shown in the figure, the theoretical value is the red part on the left, and the experimental value is the blue part on the right, which further proves that compound 9 has been successfully prepared. Figure 12 It can be seen that the sodium ion addition peak signal is: [9+Na] + , molecular formula is C 120 H 113 O 22 PNa + The theoretical value is 1960.7387, the measured value is 1960.7396, and the relative error is 0.5ppm; its carbon nuclear magnetic resonance spectrum (125MHz, CDCl3, 25℃) is as follows Figure 13 shown.

[0081] Compound 9, white solid, 1 H NMR(500MHz,Chloroform-d)δ8.07(s,2H),7.98(d,J=8.1Hz,2H),7.76(s,4H),7.50(t,J=7.4Hz,2H),7.37(d,J =8.5Hz,2H),7.33–7.28(m,2H),7.18(s,4H),7.05(s,2H),6.93–6.49(m,16H),5.95(s,2H),4.04–3.21(m,74H). 13 C NMR(125MHz,Chloroform-d)δ156.3,150.8,150.6,150.3,137.9,134.4,132.9,131.4,131.1,129.7,129.6, 128.0,127.1,126.2,125.6,114.4,114.0,112.7,55.9,55.8,55.0,31.9,31.5,31.4,30.2,30.1,29.7,29.4. 31 P NMR(202MHz,Chloroform-d)δ2.8.ESI-TOF-MS(m / z):[M+Na] + calcd for C 120 H 113 O 22 PNa + ,1960.7387; found,1960.7396,error:0.5ppm.

[0082] Application Example 1

[0083] The pillararene binaphthol chiral catalyst prepared in Example 9 was applied to asymmetric organic synthesis. In this application example, the preparation of asymmetric 2,3-dihydroquinazolin-4-(1H)ones was taken as an example.

[0084]

[0085] 6.8 mg of 2-aminobenzamide (0.05 mmol), 7.5 mg of m-anisaldehyde (0.055 mmol), 9.6 mg of pillararene binaphthol chiral catalyst compound 9 (10 mol%) and 75 mg of The molecular sieves were added to a 10 mL Shrek tube and the atmosphere was exchanged with nitrogen three times. Under a nitrogen atmosphere, 1 mL of ultra-dry chloroform was added and the reaction was stirred at room temperature for 12 h. The molecular sieves were removed by filtration, and the solvent was removed in vacuo. The mixture was then purified by column chromatography (DCM / EA = 5:1, v / v) to afford compound 10 (yield: 99%; ee: 95%).

[0086] The above results indicate that the chiral catalyst of pillararene binaphthol provided by the present invention can be successfully applied to asymmetric catalytic reactions.

[0087] The above embodiments are not limitations of the present invention, and the present invention is not limited to the above embodiments. As long as the requirements of the present invention are met, they belong to the protection scope of the present invention.

Claims

1. A pillararene binaphthol chiral catalyst, characterized in that: Its chemical structure is shown below:

2. A method for preparing the pillararene binaphthol chiral catalyst according to claim 1, characterized in that: The preparation method comprises the following steps: Step (1), dissolving (R)-(+)-1,1'-binaphthol in tetrahydrofuran (THF), and then reacting with sodium hydride (NaH) and bromomethyl methyl ether (MOMBr) to obtain compound 1; Step (2), dissolving compound 1 in tetrahydrofuran (THF), and then reacting with n-butyllithium (n-BuLi) in n-hexane and iodine to obtain compound 2; Step (3), compound 2, 1,4-phenylenediboronic acid bis(pinacol) ester, palladium catalyst, and base are mixed, and then toluene PhCH3, anhydrous ethanol and water are added to react to obtain compound 3; Step (4), mixing phenylene dimethyl ether, paraformaldehyde (CH2O)n and 1,2-dichloroethane DCE, and then adding boron trifluoride ether complex BF3·(C2H5)2O to react to obtain compound 4; Step (5), dissolving compound 4 in dichloromethane (DCM), and then adding boron tribromide (BBr3) to react to obtain compound 5; Step (6), dissolving compound 5 in dichloromethane (DCM), then adding pyridine (Py) and trifluoromethanesulfonic anhydride (Tf2O) to react to obtain compound 6; Step (7), mixing compound 3, compound 6, a palladium catalyst, a ligand and a base and dissolving them in a mixed solvent of 1,4-dioxane and deionized water to react to obtain compound 7; Step (8), dissolving compound 7 in dichloromethane (DCM), then adding trifluoroacetic acid (TFA) to react to obtain compound 8; Step (9), dissolving compound 8 in a mixed solvent of pyridine and water, and then adding phosphorus oxychloride POCl3 to react to obtain compound 9, i.e., the pillararene binaphthol chiral catalyst; The synthetic route of the reaction is as follows:

3. The preparation method according to claim 2, characterized in that The palladium catalyst in step (3) is tetrakis(triphenylphosphine)palladium Pd(PPh3)4, and the base is anhydrous sodium carbonate Na2CO3.

4. The preparation method according to claim 2, characterized in that The molar ratio of compound 3, compound 6, palladium catalyst, ligand and base in step (7) is (1-1.2):3:0.1:0.25:2.

5.

5. The preparation method according to claim 2 or 4, characterized in that The palladium catalyst in step (7) is tetrakis(triphenylphosphine)palladium Pd(PPh3)4, the ligand is triphenylphosphine, and the base is potassium phosphate.

6. The preparation method according to claim 2, characterized in that The volume ratio of 1,4-dioxane to deionized water in the mixed solvent of step (7) is (4-5):

1.

7. The preparation method according to claim 2, characterized in that The mass volume ratio of compound 7 and trifluoroacetic acid TFA in step (8) is 200 mg: (0.1-0.2) mL.

8. The preparation method according to claim 2, characterized in that The mass volume ratio of compound 8 and phosphorus oxychloride POCl3 in step (9) is 150 mg: (0.2-0.3) mL.

9. Use of the pillararene binaphthol chiral catalyst according to claim 1 in asymmetric organic catalysis.

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