Beta-substituted silicon-based amide compound and preparation method thereof

Abstract

The invention relates to a beta-substituted silicon-based amide compound and a preparation method thereof, an aldehyde ligand is selected to react with chitosan to generate chitosan Schiff base, and then the chitosan Schiff base is soaked in a saturated copper sulfate solution to adsorb copper ions to prepare a chitosan Schiff base copper functional material (Schiff-CS at Cu). An alpha-substituted acrylamide compound and (dimethylphenylsilyl) boronic acid pinacol ester are used as raw materials, and a beta-substituted silicon-based amide compound drug intermediate is prepared through catalysis of the chitosan Schiff base copper functional material. The method provided by the invention has the characteristics of being simple, safe, green and environment-friendly, the production cost can be remarkably reduced, and the purity and yield of the product are improved. The limitation of the existing synthesis scheme is expected to be broken through, and a broader way is opened up for the synthesis of the beta-substituted silicon-based amide compound drug intermediate.

Description

Technical Field

[0001] The present invention relates to the field of organic synthesis, and particularly relates to a β-substituted silylamide compound and a preparation method thereof. Background Art

[0002] Organosilicon compounds have attracted much attention due to the unique stability of their C-Si bonds. This stable chemical bond not only makes it difficult for organosilicon compounds to undergo side reactions or decomposition when used as synthetic intermediates in organic synthesis, thus ensuring the reliability of the reaction and the purity of the product, but also endows them with a wide range of application values during the functionalization process. In the structure of organosilicon compounds, the C-Si bond can be transformed into C-O bond, C-N bond and C-S bond, and the resulting compounds have various uses. For example, Insecticide silafluofen, Karenitecin (BPN1350), and Hexaphenylsilole are respectively applied to insecticides, protease inhibitors, and semiconductor materials.

[0003] However, as a very important class of intermediates in drug synthesis - β-substituted silylamide compounds, there are many challenges in their synthesis process. The difficulty in separating the products caused by homogeneous reactions not only increases the difficulty of subsequent treatment, but also affects the quality and yield of the products. In addition, the narrow substrate scope, low atom utilization rate, and potential threat to the environment are all problems that need to be solved urgently in the current synthesis scheme. (J.Am.Chem.Soc.2011,133,7324; Angew.Chem.Int.Ed.,2013,52,1; J.Am.Chem.Soc.,2014,136,16780; J.Am.Chem.Soc.,2015,137,15176; ACS Catal.,2022,12,4898) These problems not only limit the application of β-substituted silylamide compounds in drug synthesis, but also hinder their expansion in other fields. Summary of the Invention

[0004] The present invention provides a β-substituted silylamide compound and a preparation method thereof. By screening suitable ligands, a chitosan Schiff base copper functional catalytic material (Schiff-CS@Cu) is synthesized and applied to the carbon-silicon addition reaction using α-substituted acrylamide compounds as raw materials, achieving the effect of replacing the high-cost catalyst in the original process under room temperature conditions. While greatly reducing the production cost, it realizes the safe and efficient synthesis of the drug intermediate β-substituted silylamide compound, and at the same time greatly reduces environmental pollution and waste discharge, meeting the environmental protection requirements for chemical drug production enterprises in China.

[0005] The solution of the present invention to the above technical problems is as follows: A β-substituted silylamide compound, and its structural formula is as follows:

[0006]

[0007] Among them, R1 is one of a hydrogen group, a methyl group, and a phenyl group; R2 is one of a phenyl group, a p-chlorophenyl group, a p-fluorophenyl group, and a p-methoxyphenyl group.

[0008] As described above, the preparation method of the β-substituted silylamide compound has the following synthetic route:

[0009]

[0010] The synthesis steps are as follows: The α-substituted acrylamide compound I and (dimethylphenylsilyl)boronic acid pinacol ester are dissolved in a solvent, and then a chitosan Schiff base copper functional catalytic material is added, and the mixture is stirred and reacted at room temperature. After the reaction is completed, separation and purification are carried out to obtain the product β-substituted silylamide compound II, and the chitosan Schiff base copper functional catalytic material is recovered.

[0011] Preferably, the copper content in the chitosan Schiff base copper functional catalytic material is 0.5 to 1.6 mmol / g.

[0012] Preferably, the molar ratio between the copper contained in the α-substituted acrylamide compound I, (dimethylphenylsilyl)boronic acid pinacol ester, and the chitosan Schiff base copper functional catalytic material is 1 to 1.5:1:0.015 to 0.02.

[0013] Preferably, the solvent is water, and 0.2 to 1 mL of water is added per 1 mg of the chitosan Schiff base copper functional catalytic material.

[0014] Among them, the synthesis steps of the chitosan Schiff base copper functional catalytic material are as follows:

[0015] 1) Take chitosan powder and dissolve it in acetic acid to form System 1;

[0016] 2) Dissolve the ligand in absolute ethanol to form System 2;

[0017] 3) Mix System 1 and System 2 and react at 75 °C. After the reaction is completed, wash and dry with a solvent to obtain a chitosan Schiff base powder material;

[0018] 4) Mix the chitosan Schiff base powder material with 30.0 mL of saturated copper sulfate solution and stir and react at 50 °C for 6 h. After the reaction is completed, wash and dry with water to obtain the chitosan Schiff base copper functional catalytic material.

[0019] Preferably, the ligand is one of 3-pyridinecarboxaldehyde, 5-hydroxymethylfurfural, salicylaldehyde, 2-pyridinecarboxaldehyde, 4-imidazolecarboxaldehyde, 2-quinolinecarboxaldehyde, 5-bromosalicylaldehyde, 5-nitrosalicylaldehyde, L-Boc-prolinol, 5-fluorosalicylaldehyde, 3,5-di-tert-butylsalicylaldehyde, 8-hydroxyquinoline-2-carboxaldehyde.

[0020] Preferably, the ligand is 8-hydroxyquinoline-2-carboxaldehyde.

[0021] Preferably, in step 1), the amino concentration in system one is 0.62 mmol / mL.

[0022] Preferably, in step 2), the ligand concentration in system two is 0.33 mmol / mL.

[0023] The beneficial effects of the present invention are as follows: By using different ligands to synthesize green biomass-based catalysts, the present invention is environmentally friendly and low-cost; the solvent is pure water, avoiding the use of organic solvents, which is environmentally friendly and low-cost; the reaction conditions are mild and can be completed at room temperature, being safe and efficient.

[0024] The above description is only an overview of the technical solution of the present invention. In order to understand the technical means of the present invention more clearly and be able to implement it according to the content of the description, the following takes the preferred embodiments of the present invention and combines with the attached drawings to describe in detail as follows. The specific implementation manners of the present invention are given in detail by the following embodiments and their attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The attached drawings described herein are used to provide a further understanding of the present invention, constitute a part of this application, and the schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0026] Figure 1 1H NMR spectrum of the target product catalyzed by the chitosan Schiff base copper functional catalytic material (Scfiff-CS@Cu C12) in Example 2; 1 H spectrum;

[0027] Figure 2 13C NMR spectrum of the target product catalyzed by the chitosan Schiff base copper functional catalytic material (Scfiff-CS@Cu C12) in Example 2; 13 C spectrum;

[0028] Figure 3 Infrared comparison spectra of chitosan, chitosan Schiff base (Schiff-CS L12) corresponding to ligand L12, and the chitosan Schiff base copper functional catalytic material (Schiff-CS@Cu C12) prepared in Example 2;

[0029] Figure 4SEM images of chitosan Schiff base copper functional catalytic materials (Schiff-CS@Cu C12) and intermediate products; a is the SEM image of chitosan, b is the SEM image of chitosan Schiff base corresponding to L12; c is the SEM image of chitosan Schiff base copper functional catalytic material Cu(Schiff-CS@Cu C12);

[0030] Figure 5 XRD comparison spectra of chitosan, chitosan Schiff base (Schiff-CS L12) corresponding to ligand L12, and chitosan Schiff base copper functional catalytic material (Schiff-CS@Cu C12) prepared in Example 2;

[0031] Figure 6 Thermogravimetric curves of chitosan, chitosan Schiff base (Schiff-CS L12) corresponding to ligand L12, and chitosan Schiff base copper functional catalytic material (Schiff-CS@Cu C12) prepared in Example 2;

[0032] Figure 7 SEM spectra of chitosan Schiff base copper functional catalytic material (Schiff-CS@Cu C12) after 6 cycles of use in Example 3;

[0033] Figure 8 1H NMR spectrum of the product in Example 4 1 ;

[0034] Figure 9 13C NMR spectrum of the product in Example 4 13 ;

[0035] Figure 10 1H NMR spectrum of the product in Example 5 1 ;

[0036] Figure 11 13C NMR spectrum of the product in Example 5 13 ;

[0037] Figure 12 1H NMR spectrum of the product in Example 6 1 ;

[0038] Figure 13 13C NMR spectrum of the product in Example 6 13 ;

[0039] Figure 14 1H NMR spectrum of the product in Example 7 1 ;

[0040] Figure 15 13C NMR spectrum of the product in Example 7 13 ; Detailed implementation methods

[0041] The principles and features of the present invention will be described below in conjunction with the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention. The drugs used in the examples are all commercially available products without special instructions, and the methods used are all conventional methods in the art. The viscosity of the chitosan powder used in the present invention is 100-200 Pa·s, and each 1 g of chitosan contains approximately 6.2 mmol -NH2.

[0042] Example 1

[0043] This example provides a preparation method for a variety of chitosan Schiff base copper functional catalytic materials (Schiff-CS@Cu C1–C12), including the following steps:

[0044] 1) Add 1 g of chitosan powder and 10.0 mL of acetic acid solution to a 250.0 mL beaker to form System 1;

[0045] 2) Add 24.8 mmol of ligand L1 (3-pyridinecarboxaldehyde) to 75.0 mL of absolute ethanol to form System 2

[0046] 3) Mix System 1 and System 2 and add them to a 250.0 mL round-bottom flask. Heat under reflux at 75 °C for 12 h, filter, wash with absolute ethanol until the filtrate is colorless to remove excess aldehyde compounds, then wash with deionized water until neutral, and dry under vacuum at 50 °C to obtain chitosan Schiff base powder material (Schiff-CS L1).

[0047] 4) Add the prepared chitosan Schiff base powder (Schiff-CS) to a 100 mL flask containing 30.0 mL of saturated copper sulfate solution, stir at 50 °C for 6 h to adsorb copper ions, finally filter and separate, wash with deionized water to remove free sulfate ions and free copper ions, and dry at 50 °C for 12 h to obtain chitosan Schiff base copper functional material (Schiff-CS@Cu C1).

[0048] Keeping other steps unchanged, replace ligand L1 (3-pyridinecarboxaldehyde) in step 2) with ligands L2-L12 (5-hydroxymethylfurfural, salicylaldehyde, 2-pyridinecarboxaldehyde, 4-imidazolecarboxaldehyde, 2-quinolinecarboxaldehyde, 5-bromosalicylaldehyde, 5-nitrosalicylaldehyde, L-Boc-prolinaldehyde, 5-fluorosalicylaldehyde, 3,5-di-tert-butylsalicylaldehyde, and 8-hydroxyquinoline-2-carboxaldehyde)), to obtain chitosan Schiff base copper functional materials Schiff-CS@Cu C2……Schiff-CS@Cu C12.

[0049] The structural formulas of ligands L1-L2 are as follows:

[0050]

[0051] Characterization tests were carried out on the chitosan Schiff base copper functional catalytic material (Schiff-CS@Cu C1–C12) for metal content, and the copper ion loading is shown in Table 1.

[0052] Table 1 Copper ion loading of chitosan Schiff base copper functional catalytic material (Schiff-CS@Cu C1–C12)

[0053]

[0054] Example 2

[0055] A variety of chitosan Schiff base copper functional catalytic materials (Schiff-CS@Cu C1–C12) prepared in Example 1 were applied to the reaction of N,2-diphenylacrylamide and (dimethylphenylsilyl)boronic acid pinacol ester to prepare 3-dimethyl(phenyl)silyl-N,2-diphenylpropanamide, and its synthesis route is as follows:

[0056]

[0057] The synthesis steps are as follows:

[0058] 1) Under room temperature conditions, a magnetic stir bar, 55.7 mg of N,2-diphenylacrylamide, 52.4 mg of (dimethylphenylsilyl)boronic acid pinacol ester, and 2.0 mL of water were successively added to a 2.5 mL reaction flask.

[0059] 2) 5.0 mg of Scfiff-CS@Cu C1 catalyst was added, and the mixture was stirred at room temperature (about 25 °C) for 12 h.

[0060] 3) After the reaction was completed, the mixed system was separated and purified to obtain the corresponding 3-dimethyl(phenyl)silyl-N,2-diphenylpropanamide product and the chitosan Schiff base copper functional catalytic material (Schiff-CS@Cu C1) was recovered.

[0061] Using the same method and conditions, the chitosan Schiff base copper functional catalytic materials (Schiff-CS@Cu C2–C12) prepared by replacing Scfiff-CS@Cu C1 with ligand L2-ligand 12. The yield results of each catalytic reaction product are shown in Table 2. It can be seen that the chitosan Schiff base copper functional catalytic material Schiff-CS@Cu C12 prepared from ligand L12 has the best catalytic effect, and the best Schiff base is ligand L12 (8-hydroxyquinoline-2-carboxaldehyde)

[0062] Table 1 Reaction yields of chitosan Schiff base copper functional catalytic material (Schiff-CS@Cu C1–C12)

[0063]

[0064] The 1H NMR and 13C NMR spectra of the target product catalyzed by the chitosan Schiff base copper functional catalytic material (Scfiff-CS@Cu C12) are shown below (the spectra are as Figure 1-2 shown):

[0065] 1 H NMR(400MHz,Chloroform-d)δ=0.10(s,3H),0.16(s,3H),1.42(dd,J=14.8,9.0Hz,1H),1.84(dd,J=14.8,6.4Hz,1H),3.52–3.42(m,1H),6.91(s,1H),7.05(t,J=7.4Hz,1H),7.24(d,J=8.0Hz,2H),7.33–7.27(m,4H),7.39–7.33(m,5H),7.46(d,J=4.8Hz,2H).

[0066] 13 C NMR(100MHz,Chloroform-d)δ=-2.4,20.3,50.3,119.7,124.3,127.7,128.0,128.1,129.0,129.1,129.2,133.8,138.0,138.5,141.2,172.5.

[0067] To understand the structure, composition, physicochemical properties and morphological characteristics of the chitosan Schiff base copper functional catalytic material (Scfiff-CS@Cu C12), infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM) characterizations were carried out.

[0068] As Figure 3 shown, infrared characterizations were performed on Scfiff-CS@Cu C12, chitosan (CS), and the corresponding chitosan Schiff base powder material (Schiff-CS L12) prepared in step 3) of Example 1. For chitosan, characteristic absorption peaks appear at 3289 cm -1 (O-H stretching vibration), 2873 cm -1 , 1646 cm -1 , 1583 cm -1 and 1374 cm -1 (N-H bending vibration), 1149 cm -1 (C-O-C stretching vibration) and 1026 cm-1. Compared with the FTIR spectrum of chitosan, the band at 1646 cm -1 in Schiff-CS becomes 1645 cm -1, and becomes stronger, which may be due to the C=N stretching vibration. In addition, peaks were found at 1564 - 1467 cm -1 and 872 - 719 cm -1 , which are attributed to the bending vibration and stretching vibration of the quinoline skeleton, respectively. The above changes indicate that 8-hydroxyquinoline-2-carbaldehyde is introduced into chitosan by forming Schiff base. Differences were also found in the FTIR spectrum of Schiff-CS@Cu L13: the band at 1645 cm -1 (C=N stretching vibration) becomes 1593 cm -1 , and becomes weaker, which is due to the coordination of the imine group and copper. In addition, the quinoline bands at 1519 - 1443 cm -1 and 745 cm -1 become weaker, which may also be attributed to the complexation of copper and quinoline.

[0069] As Figure 4 shown, from the SEM morphologies of Scfiff-CS@Cu C12, chitosan (CS), and the corresponding chitosan Schiff base powder material (Schiff-CS L12) prepared in step 3) of Example 1, it can be seen that the surface becomes rougher after grafting 8-hydroxyquinoline-2-carbaldehyde to modify chitosan ( Figure 4 a and Figure 4 b), indicating that the desired chemical modification has been achieved. The surface of Schiff-CS@Cu C12 becomes rougher ( Figure 4 c), where the aggregated fine particles indicate that CuSO4 has been successfully adsorbed onto the 8-hydroxyquinoline-2-carbaldehyde modified chitosan material.

[0070] As Figure 5 shown, from the XRD comparison spectra of Scfiff-CS@Cu C12, chitosan (CS), and the corresponding chitosan Schiff base powder material (Schiff-CS L12) prepared in step 3) of Example 1, it can be seen that a broad diffraction peak is shown at the angle 2θ = 19.37° - 21.60°, which indicates that chitosan has high crystallinity. On the other hand, for Schiff-CS L12, a decrease in the crystallinity value, peak intensity, and width was observed, and new diffraction peaks appeared at 2θ = 12.03° and 2θ = 41.29°, which may be due to the deformation of hydrogen bonds and the decrease in the number of free amino groups on chitosan after the formation of Schiff base. In the XRD spectrum of Schiff-CS@Cu C12, various peaks with reduced intensity were observed between the angles 2θ = 5° - 30°, which indicates a decrease in crystallinity compared to their ligands. Therefore, it can be concluded that divalent copper ions have coordinated with the Schiff base ligand.

[0071] As Figure 6As shown, from the thermogravimetric curves of Scfiff-CS@Cu C12, chitosan (CS), and the corresponding chitosan Schiff base powder material (Schiff-CS L12) prepared in step 3) of Example 1, it can be seen that when heated under N2 protection, they have two different mass loss stages. The first stage has a temperature range of 50 - 100 °C, which may be the loss of crystal water. In the second stage of mass loss, the decomposition of these materials occurs between 200 °C and 300 °C. It is worth noting that due to the formation of Schiff base, the stability of Schiff-CS is lower than that of chitosan, and due to the coordination of copper, the stability of Schiff-CS@Cu C12 is lower than that of chitosan and Schiff-CS. At the same time, its content is higher than other compounds, indicating the presence of loaded metal copper ions in the residue. Importantly, Schiff-CS@Cu C12 is stable up to 200 °C, proving that this catalytic material is suitable for catalytic systems operating at high temperatures.

[0072] Example 3

[0073] To further explore the recycling effect of the chitosan Schiff base copper functional material Shiff-CS@Cu C12, the Shiff-CS@Cu C12 recovered in Application Example 1 was used as the catalytic material. Still using N,2-diphenylacrylamide and (dimethylphenylsilyl)boronic acid pinacol ester as raw materials, 3-dimethyl(phenyl)silyl-N,2-diphenylpropanamide was catalytically prepared under the same steps and conditions. After each reaction, the recovered chitosan Schiff base copper functional material Shiff-CS@Cu C12 was washed successively with distilled water and absolute ethanol, and then placed in an oven at 40 °C for drying, so as to be used in the next cycle reaction.

[0074] After 6 cycles, the target product can still be obtained with a relatively high yield. Among them, the chitosan Schiff base copper functional material Shiff-CS@Cu C12 obtained the target product with yields of 95%, 96%, 95%, 93%, 94%, and 92% respectively.

[0075] The Shiff-CS@Cu C12 recovered after 6 cycles was tested by ICP-OES. The results showed that the copper content remained basically unchanged, and there was basically no leaching of copper particles during the reaction process. As Figure 7 shown, the surface morphology of the Shiff-CS@CuC12 recovered after 6 cycles did not change significantly compared with that before the reaction.

[0076] In summary, it is proved that the functional material Schiff-CS@Cu C12 has good recyclability and excellent stability.

[0077] Example 4

[0078] Using the chitosan Schiff base copper functional material Shiff-CS@Cu C12 prepared in Example 1, acrylamide and (dimethylphenylsilyl)boronic acid pinacol ester were used as raw materials for catalytic reaction to prepare 3-dimethyl(phenyl)silylpropanamide, and its synthetic route is as follows:

[0079]

[0080] The synthesis steps are as follows:

[0081] 1) Under room temperature conditions, a magnetic stir bar, 17.0 mg of acrylamide, 52.4 mg of (dimethylphenylsilyl)boronic acid pinacol ester, and 2.0 mL of water were successively added to a 2.5 mL reaction flask.

[0082] 2) 5.0 mg of Scfiff-CS@Cu C12 catalyst was added, and the mixture was stirred at room temperature (about 25 °C) for 12 h.

[0083] 3) After the reaction was completed, the mixed system was separated and purified to obtain the corresponding 3-dimethyl(phenyl)silyl-N,2-diphenylpropanamide and the chitosan Schiff base copper functional catalytic material (Schiff-CS@Cu C12) was recovered.

[0084] After testing, the yield of the target product was 93%.

[0085] The 1H NMR and 13C NMR spectra of the target product are as follows (the spectra are as Figure 8-9 shown):

[0086] 1 H NMR(400MHz,Chloroform-d)δ=0.30(s,6H),1.14–1.03(m,2H),2.24–2.14(m,2H),5.41(s,2H),7.36(dd,J=4.9,1.9Hz,3H),7.50(dd,J=6.6,3.1Hz,2H).

[0087] 13 C NMR(100MHz,Chloroform-d)δ=-3.2,11.2,30.4,128.0,129.3,133.7,138.2,176.7.

[0088] Example 5

[0089] Using the chitosan Schiff base copper functional material Shiff-CS@Cu C12 prepared in Example 1, N-(4-methoxyphenyl)methacrylamide and (dimethylphenylsilyl)boronic acid pinacol ester were used as raw materials for the catalytic reaction to prepare 3-dimethyl(phenyl)silyl-N-(4-methoxyphenyl)-2-methylpropanamide. The synthetic route is as follows:

[0090]

[0091] The synthesis steps are as follows:

[0092] 1) Under room temperature conditions, a magnetic stir bar, 45.9 mg of N-(4-methoxyphenyl)methacrylamide, 52.4 mg of (dimethylphenylsilyl)boronic acid pinacol ester, and 2.0 mL of water were successively added to a 2.5 mL reaction flask.

[0093] 2) 5.0 mg of Scfiff-CS@Cu C12 catalyst was added, and the mixture was stirred at room temperature (about 25 °C) for 12 h.

[0094] 3) After the reaction was completed, the mixed system was separated and purified to obtain the corresponding 3-dimethyl(phenyl)silyl-N-(4-methoxyphenyl)-2-methylpropanamide and the chitosan Schiff base copper functional catalytic material (Schiff-CS@CuC12) was recovered.

[0095] After testing, the yield of the target product was 93%.

[0096] The 1H NMR and 13C NMR spectra of the target product are as follows (the spectra are as Figure 10-11 shown):

[0097] 1 H NMR (400 MHz, Chloroform-d) δ = 0.31 (d, J = 1.6 Hz, 6H), 1.01 (dd, J = 14.9, 6.9 Hz, 1H), 1.21 (d, J = 6.8 Hz, 3H), 1.32 (dd, J = 14.8, 7.6 Hz, 1H), 2.33 (q, J = 7.0 Hz, 1H), 3.78 (s, 3H), 6.83 (d, J = 9.0 Hz, 3H), 7.43–7.25 (m, 5H), 7.52 (dd, J = 6.5, 3.1 Hz, 2H).

[0098] 13 C NMR (100 MHz, Chloroform-d) δ = -2.6, -2.0, 21.5, 21.6, 38.6, 55.6, 114.2, 121.6, 128.1, 129.3, 131.2, 133.8, 138.8, 156.3, 175.2.

[0099] Example 6

[0100] Using the chitosan Schiff base copper functional material Shiff-CS@Cu C12 prepared in Example 1, ethyl-4-(2-phenylacrylamido)benzoate and (dimethylphenylsilyl)boronic acid pinacol ester were used as raw materials for catalytic reaction to prepare ethyl-4-(3-dimethyl(phenyl)silyl-2-phenylpropanamido)benzoate. The synthetic route is as follows:

[0101]

[0102] The synthesis steps are as follows:

[0103] 1) Under room temperature conditions, a magnetic stir bar, 68.2 mg of ethyl-4-(2-phenylacrylamido)benzoate, 52.4 mg of (dimethylphenylsilyl)boronic acid pinacol ester, and 2.0 mL of water were successively added to a 2.5 mL reaction flask.

[0104] 2) 5.0 mg of Scfiff-CS@Cu C12 catalyst was added and stirred at room temperature (about 25 °C) for 12 h.

[0105] 3) After the reaction was completed, the mixed system was separated and purified to obtain the corresponding ethyl-4-(3-dimethyl(phenyl)silyl-2-phenylpropanamido)benzoate and the chitosan Schiff base copper functional catalytic material (Schiff-CS@CuC12) was recovered.

[0106] After testing, the yield of the target product was 95%.

[0107] The 1H NMR and 13C NMR spectra of the target product are as follows (the spectra are as Figure 12-13 shown):

[0108] 1 H NMR(400MHz,Chloroform-d)δ=0.08(s,3H),0.13(s,3H),1.34(t,J=7.1Hz,3H),1.42(dd,J=14.8,8.9Hz,1H),1.80(dd,J=14.8,6.5Hz,1H),3.50(dd,J=8.9,6.5Hz,1H),4.30(q,J=7.1Hz,2H),7.36–7.20(m,9H),7.47–7.38(m,4H),7.90(d,J=8.5Hz,2H).

[0109] 1313C NMR (100 MHz, Chloroform-d) δ = -2.8, -2.4, 14.4, 20.4, 50.3, 61.0, 118.7, 125.8, 127.8, 127.9, 128.0, 129.1, 129.2, 130.7, 133.7, 138.2, 140.9, 142.1, 166.3, 172.8.

[0110] Example 7

[0111] Using the chitosan Schiff base copper functional material Shiff-CS@Cu C12 prepared in Example 1, 2-phenyl-N-tricosanoylaminoacrylamide and (dimethylphenylsilyl)boronic acid pinacol ester were used as raw materials for catalytic reaction to prepare 3-dimethyl(phenyl)silyl-2-phenyl-N-tricosylpropanamide. The synthetic route is as follows

[0112]

[0113] The preparation steps are as follows:

[0114] 1) Under room temperature conditions, a magnetic stir bar, 110.8 mg of 2-phenyl-N-tricosanoylaminoacrylamide, 52.4 mg of (dimethylphenylsilyl)boronic acid pinacol ester, and 2.0 mL of water were successively added to a 2.5 mL reaction flask.

[0115] 2) 5.0 mg of Scfiff-CS@Cu catalyst was added, and the mixture was stirred at room temperature (about 25 °C) for 12 h.

[0116] 3) After the reaction was completed, the mixed system was separated and purified to obtain the corresponding 3-dimethyl(phenyl)silyl-2-phenyl-N-tricosylpropanamide and the chitosan Schiff base copper functional catalytic material (Schiff-CS@Cu C12) was recovered.

[0117] After testing, the yield of the target product was 93%.

[0118] The 1H NMR and 13C NMR spectra of the target product are as follows (the spectra are as Figure 14-15 shown):

[0119] 11H NMR (400 MHz, Chloroform-d) δ = 0.01 (s, 3H), 0.04 (s, 3H), 0.81 (t, J = 6.7 Hz, 3H), 1.34–0.99 (m, 23H), 1.70 (dd, J = 14.8, 6.4 Hz, 1H), 3.02 (q, J = 6.7 Hz, 2H), 3.26 (dd, J = 9.1, 6.4 Hz, 1H), 5.18 (s, 1H), 7.23–7.10 (m, 5H), 7.28–7.23 (m, 3H), 7.36 (dd, J = 7.0, 2.5 Hz, 2H).

[0120] 13 13C NMR (100 MHz, Chloroform-d) δ = -2.8, -2.4, 14.3, 20.2, 22.8, 26.9, 29.3, 29.48, 29.51, 29.6, 29.7, 29.8, 32.0, 39.8, 49.2, 127.3, 127.8, 128.0, 128.8, 129.0, 133.8, 138.8, 142.0, 174.2.

[0121] As described above, it is only the preferred embodiment of the present invention, and it does not impose any form of limitation on the present invention; any ordinary technician in the industry can smoothly implement the present invention according to what is shown in the accompanying drawings of the specification and what is described above; however, any slight changes, modifications and equivalent variations made by those skilled in the art within the scope of the technical solution of the present invention by using the technical content disclosed above are all equivalent embodiments of the present invention; at the same time, any equivalent changes, modifications and variations made to the above embodiments based on the essential technology of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A β-substituted silicon-based amide compound, characterized in that: Its structural formula is as follows: Among them, R1 is one of hydrogen, methyl, and phenyl; R2 is one of phenyl, p-chlorophenyl, p-fluorophenyl, and p-methoxyphenyl.

2. A method for preparing the β-substituted silicon-based amide compound according to claim 1, characterized in that: The synthetic route is as follows: The synthesis steps are as follows: α-substituted acrylamide compound I and (dimethylphenylsilyl)boronic acid pinacol ester are dissolved in a solvent, chitosan Schiff base copper functional catalyst material is added, and the reaction is stirred at room temperature. After the reaction is completed, separation and purification are performed to obtain the product β-substituted silicon-based amide compound II, and the chitosan Schiff base copper functional catalyst material is recovered.

3. The method for preparing a β-substituted silicon-based amide compound according to claim 2, characterized in that: The copper content in the chitosan Schiff base copper functional catalytic material is 0.5-1.6 mmol / g.

4. The method for preparing a β-substituted silicon-based amide compound according to claim 3, characterized in that: The molar ratio of the α-substituted acrylamide compound I, (dimethylphenylsilyl)boric acid pinacol ester and the copper contained in the chitosan Schiff base copper functional catalytic material is 1-1.5:1:0.015-0.

02.

5. The method for preparing a β-substituted silicon-based amide compound according to claim 3, characterized in that: The solvent is water, and 0.2-1 mL of water is added for every 1 mg of chitosan Schiff base copper functional catalytic material.

6. The method for preparing a β-substituted silicon-based amide compound according to claim 2, characterized in that: The synthesis steps of chitosan Schiff base copper functional catalytic material are as follows: 1) dissolving chitosan powder in acetic acid to form system 1; 2) The ligand is dissolved in anhydrous ethanol to form system 2; 3) mixing system 1 and system 2, reacting at 75° C., and after the reaction, washing with a solvent and drying to obtain a chitosan Schiff base powder material; 4) The chitosan Schiff base powder material was mixed with 30.0 mL of saturated copper sulfate solution, and stirred for reaction at 50° C. for 6 h. After the reaction was completed, the chitosan Schiff base copper functional catalytic material was obtained by washing with water and drying.

7. The method for preparing a β-substituted silicon-based amide compound according to claim 6, characterized in that: The ligand is one of 3-pyridinecarboxaldehyde, 5-hydroxymethylfurfural, salicylaldehyde, 2-pyridinecarboxaldehyde, 4-imidazolecarboxaldehyde, 2-quinolinecarboxaldehyde, 5-bromosalicylaldehyde, 5-nitrosalicylicylaldehyde, L-Boc-prolinealdehyde, 5-fluorosalicylaldehyde, 3,5-di-tert-butylsalicylaldehyde, and 8-hydroxyquinoline-2-carboxaldehyde.

8. The method for preparing a β-substituted silicon-based amide compound according to claim 7, characterized in that: The ligand is 8-hydroxyquinoline-2-carboxaldehyde.

9. The method for preparing a β-substituted silicon-based amide compound according to claim 6, characterized in that: In the step 1), the amino concentration in system 1 is 0.62 mmol / mL.

10. The method for preparing a β-substituted silicon-based amide compound according to claim 6, characterized in that: In the step 2), the ligand concentration in system 2 is 0.33 mmol / mL.

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