Method for preparing nitrogen-containing polymer and application

Abstract

The invention provides a nitrogen-containing polymer as well as a preparation method and application thereof, and belongs to the technical field of polymer synthesis. The method provided by the invention can be used for synthesizing the nitrogen-containing polymer with controllable molecular weight and narrow molecular weight distribution, the preparation method is simple, the condition is mild, and a reaction system does not need special protective gas. Besides, the main chain of the nitrogen-containing polymer contains a cinnamate structure, so that the nitrogen-containing polymer can be completely degraded under an alkaline condition, and has a wide application prospect in the fields of biotechnology and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer synthesis, and specifically, to a method for preparing nitrogen-containing polymers and their applications. Background Art

[0002] Aziridine and azetidine have broad application prospects in the biomedical field due to their good biocompatibility, antibacterial activity, and antitumor activity. However, the non-degradability of traditional polymer materials is a major obstacle to their application in vivo. To better meet the needs of the biomedical field, it is necessary to develop polymer materials with degradability. In the field of biotechnology, nitrogen-containing polymers have been used as nucleic acid delivery agents, reactive drug delivery systems, and antibacterial materials. Structural factors such as amine density (i.e., the distance between nitrogens in the backbone) have a significant impact on properties such as cytotoxicity, transfection efficiency, and antibacterial activity. However, most of the currently used nitrogen-containing polymers are polymerized using traditional nitrogen-containing monomers (aziridine and azetidine). These traditional nitrogen-containing monomers (aziridine and azetidine) have a structure with only two carbons (C2N1) or three carbons (C3N1) between the backbone amines, and this amine density limits their application in biotechnology.

[0003] Traditionally, the preparation of nitrogen-containing polymers usually adopts the stepwise polymerization method, which leads to uncontrollable polymer molecular weight and a wide molecular weight distribution. In contrast, chain polymerization reactions can synthesize nitrogen-containing polymers in a controllable manner, thereby obtaining products with controllable molecular weight and narrow distribution. However, currently, such methods are still relatively limited, and most require the use of nitrogen-containing cyclic monomers with ring strain (such as aziridine and azetidine) for polymerization. Therefore, it is quite difficult to introduce additional functional groups into the main chain of nitrogen-containing polymers, which severely limits their application scope. Therefore, it is particularly necessary to explore and develop efficient and controllable methods for preparing nitrogen-containing polymers. The development of such a method is expected to further promote the application of nitrogen-containing polymers in the field of polymer science. The prior art discloses a novel palladium-catalyzed chain-growth polymerization reaction for synthesizing nitrogen-rich polymers, based on a palladium-phosphoramide ligand-catalyzed chain-growth polymerization reaction, using N-sulfonylvinylazepine as a monomer. Through an oxidative addition reaction, a π-allyl intermediate is generated, and then the polymerization reaction is realized, achieving the introduction of heteroatoms into the polymer main chain, but the goal of introducing functional groups onto the polymer main chain cannot be achieved.

[0004] Therefore, the present invention develops a method for preparing nitrogen-containing polymers and their applications, which conducts controllable ring-opening polymerization on cycloallylamine monomers to obtain degradable nitrogen-containing polymers with controllable molecular weight and narrow molecular weight distribution and containing cinnamate structures, having important research significance. Summary of the Invention

[0005] The primary objective of the present invention is to overcome the deficiencies of the prior art and provide a method for preparing nitrogen-containing polymers and their applications. The method for preparing nitrogen-containing polymers provided by the present invention is the Michael addition-fragmentation ring-opening polymerization (MAFROP) method, that is, the cycloallylamine monomer, initiator, and organic solvent undergo controlled ring-opening polymerization under room temperature air to obtain a nitrogen-containing polymer with a controllable molecular weight and a narrow molecular weight distribution and containing a cinnamate structure.

[0006] Another objective of the present invention is to provide a nitrogen-containing polymer prepared by the above method.

[0007] Another objective of the present invention is to provide an application of the above nitrogen-containing polymer.

[0008] To achieve the above invention objectives, the present invention adopts the following technical solutions:

[0009] The present invention protects a method for preparing a nitrogen-containing polymer, which is a reaction of a cycloallylamine monomer, an initiator, and an organic solvent under room temperature air;

[0010] The cycloallylamine monomer includes one of M1, M2, M3, M4, or M5:

[0011]

[0012] The general structural formula of the nitrogen-containing polymer is as follows:

[0013]

[0014] Among them, R is a group with any of the following structures:

[0015]

[0016] Among them, --- represents the substitution position; n does not exceed 100.

[0017] The method for preparing the nitrogen-containing polymer provided by the present invention is a Michael addition-fragmentation ring-opening polymerization (MAFROP) reaction, which directly realizes the controlled ring-opening polymerization of the cycloallylamine monomer under room temperature air to obtain a main-chain functional polyamine with a controllable molecular weight and a narrow molecular weight distribution and containing a cinnamate structure, and can further prepare a macroinitiator for chain extension synthesis of block functional polymers or polymers with an ester group-functional sequence in the main chain. The present invention can synthesize polymers with different molecular weights and narrow molecular weight distributions by regulating the monomer / initiator ratio.

[0018] Preferably, the structure of the nitrogen-containing polymer is P1, P2, P3, P4, or P5:

[0019]

[0020] Preferably, the structure of the initiator includes one of Init1, Init2, Init3, Init4, Init5 or Init6:

[0021]

[0022] Preferably, the number-average molecular weight of the nitrogen-containing polymer is 0.39 to 29,500, and the dispersity is 1.0 to 1.2.

[0023] The dispersity can be used to judge whether a polymerization reaction is controllable. A dispersity less than 1.3 indicates that the polymerization reaction is controllable, and during the polymerization process, the processes of chain initiation, growth, and termination are highly synchronous. For example, in living polymerization, all chains are initiated simultaneously and grow at a uniform rate, without random termination or chain transfer, and there are no other side reactions. Polymers with a narrow distribution usually have a more uniform chain length and may exhibit higher tensile strength and a more distinct thermal transition point. A narrow distribution usually indicates a high level of reaction control and product homogeneity, and the resulting polymers are more homogeneous and stable.

[0024] Preferably, the molar ratio of the cycloallylamine monomer to the initiator is 10:1 to 100:1.

[0025] Preferably, the concentration of the cycloallylamine monomer is 0.05 M to 0.6 M.

[0026] Preferably, the concentration of the cycloallylamine monomer is one of 0.05 M, 0.1 M, 0.2 M, 0.4 M or 0.6 M.

[0027] Preferably, the reaction temperature is 25 °C.

[0028] Preferably, the organic solvent is selected from one or more of N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone or acetonitrile.

[0029] Preferably, the addition amount of the organic solvent is 1 mL.

[0030] Preferably, the reaction time of the addition-fragmentation ring-opening polymerization reaction is 2 to 24 h.

[0031] The present invention also protects a nitrogen-containing polymer prepared by the method for preparing a nitrogen-containing polymer described above.

[0032] The nitrogen-containing polymer provided by the present invention has a controllable molecular weight and a narrow molecular weight distribution, and is a degradable polymer material with good application prospects, which can be further applied to the field of medical materials.

[0033] The above-mentioned nitrogen-containing polymer can be further used to prepare block copolymers or polymers with an ester-functional sequence in the main chain.

[0034] Specifically, the block copolymer is a nitrogen-containing polymer P1 embedded in P2 to obtain P1-b-P2. The prepared block copolymer has

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] The present invention provides a method for preparing a nitrogen-containing polymer, which is the Michael addition-fragmentation ring-opening polymerization (MAFROP) method, that is, a cycloallylamine monomer, an initiator, and an organic solvent are subjected to controlled ring-opening polymerization at room temperature in air to obtain a nitrogen-containing polymer with a controllable molecular weight and a narrow molecular weight distribution and containing a cinnamate structure. The method provided by the present invention can regulate the molecular weight and molecular weight distribution by adjusting the ratio of monomer / initiator, and introduce different functional groups into the polymer main chain. The nitrogen-containing polymer provided by the present invention is a biodegradable polymer material with good application prospects in the field of medical materials. Description of the Drawings

[0037] Figure 1 It is a GPC curve graph of monomer M1 undergoing a polymerization reaction under different initiator conditions;

[0038] Figure 2 It is a GPC curve graph of monomer M1 undergoing a polymerization reaction under different solvent conditions;

[0039] Figure 3 It is a GPC curve graph of monomer M1 undergoing a polymerization reaction under different concentration conditions;

[0040] Figure 4 It is a GPC curve graph of monomer M1 undergoing a polymerization reaction under different monomer / initiator ratios;

[0041] Figure 5 It is a GPC curve graph of monomer M2 undergoing a polymerization reaction under different monomer / initiator ratios;

[0042] Figure 6 It is a GPC curve graph of monomer M3 undergoing a polymerization reaction under different monomer / initiator ratios;

[0043] Figure 7 It is a relationship curve graph of monomer conversion rate and reaction time of M1 polymerization reaction;

[0044] Figure 8 It is a relationship curve graph of polymer molecular weight and monomer conversion rate of M1 polymerization reaction;

[0045] Figure 9 It is the 1H NMR spectrum of the block copolymer P1-b-P2;

[0046] Figure 10 It is a GPC curve graph for preparing the block copolymer P1-b-P2;

[0047] Figure 11 1H NMR spectrum of polymer P4 with an ester group functional sequence in the main chain;

[0048] Figure 12 Sodium methoxide degradation experiment. Detailed implementation manners

[0049] The present invention will be further described below in conjunction with embodiments. These embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. For the experimental methods without specific conditions indicated in the following embodiments, they are generally carried out according to the conventional conditions in the art or according to the conditions recommended by the manufacturer; the raw materials, reagents, etc. used, unless otherwise specified, are all raw materials and reagents that can be obtained from commercial channels such as the conventional market. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention fall within the scope of protection required by the present invention.

[0050] I. Preparation of cycloallylamine monomer

[0051] 1. Preparation of cycloallylamine monomer M1

[0052]

[0053] A reaction mixture of benzaldehyde (53.1 g, 0.5 mol), tert-butyl acrylate (64.1 g, 0.5 mol) and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU, 45.7 g, 0.3 mol) was stirred at room temperature for 96 hours. The reaction was diluted with ethyl acetate (100 mL). The organic phase was washed with 1M aq. HCl (5 × 50 mL) and saturated brine (50 mL), and dried with Na 2 SO 4 and then concentrated. The residue of benzaldehyde and tert-butyl acrylate was distilled under reduced pressure to obtain a yellow liquid (58.3 g). To an ice-water bath solution of this product (58.3 g, 248.8 mmol) in dichloromethane (50 mL) was added di-tert-butyl dicarbonate (54.3 g, 248.8 mmol) and N,N-dimethylaminopyridine (DMAP, 1.5 g, 12.4 mmol). The reaction mixture was stirred at room temperature for two hours. The reaction mixture was then washed with 1M aq. HCl (2 × 50 mL) and saturated brine (50 mL), dried with Na 2 SO 4 filtered, and concentrated in vacuo. The residue was purified by column chromatography to obtain a white solid compound 1 (38.3 g, yield 46%). 1 1H NMR (400 MHz, CDCl 3) δ 7.37 - 7.23 (m, 5H), 6.42 (s, 1H), 6.29 (s, 1H), 5.75 (s, 1H), 1.42 (s, 9H), 1.33 (s, 9H). 13 C NMR (100 MHz, CDCl 3 ) δ 164.0, 152.4, 141.1, 137.7, 128.3, 128.3, 127.8, 124.4, 82.2, 81.2, 76.0, 27.8, 27.7.

[0054] The reaction mixture of compound 1 (3.3 g, 10.0 mmol), sulfonamide 2 (3.4 g, 10.0 mmol) and 1,4 - diazabicyclo[2.2.2]octane (DABCO, 224 mg, 2.0 mmol) in THF (50 mL) was stirred at room temperature for 2 h. After the reaction was completed, the solvent was evaporated under reduced pressure, and the residue was dissolved in ethyl acetate (20 mL). The organic layer was washed with 1 M aqueous HCl (3 × 20 mL) and saturated brine (30 mL), and dried over Na 2 SO 4 and concentrated in vacuo. The crude product was purified by column chromatography to give compound 3 as a colorless oil (3.4 g, yield 61%). 1 H NMR (400 MHz, CDCl 3 ) δ 7.66 (d, J = 8.3 Hz, 2H), 7.23 - 7.13 (m, 5H), 7.06 - 6.99 (m, 2H), 6.22 (s, 1H), 6.10 (s, 1H), 5.36 (s, 1H), 3.32 - 3.08 (m, 4H), 2.35 (s, 3H), 1.60 - 1.46 (m, 1H), 1.19 (s, 9H), 1.02 - 0.89 (m, 1H), 0.78 (s, 9H), -0.11 (s, 6H). 13 C NMR (100 MHz, CDCl 3 ) δ 165.1, 143.0, 140.6, 137.9, 137.7, 129.4, 128.5, 127.8, 127.4, 126.0, 81.2, 61.9, 60.7, 43.7, 33.1, 27.6, 25.8, 21.4, 18.1, -5.5.

[0055] To a solution of Compound 3 (3.4 g, 6.0 mmol) in water (10 mL) and THF (10 mL) was added acetic acid (30 mL). The reaction mixture was stirred at room temperature for 12 h. After completion of the reaction, the solvent was removed under reduced pressure, and the residue was dissolved in ethyl acetate (20 mL). This organic layer was washed with saturated sodium bicarbonate solution (3 × 20 mL) and saturated brine (30 mL), and dried over Na 2 SO 4 and concentrated in vacuo to give a colorless oil. This colorless oil was dissolved in 1,4-dioxane (9 mL), and then 6 M aq. HCl (9 mL) was added. The reaction mixture was refluxed at 90 °C for 1.5 h. After cooling to room temperature, the reaction mixture was diluted with water (50 mL) and extracted with ethyl acetate (2 × 50 mL). The organic layer was washed with saturated brine (3 × 50 mL), and dried over Na 2 SO 4 and concentrated in vacuo to give white solid Compound 4 (2.2 g, yield 97%). 1 1H NMR (400 MHz, DMSO-d 6 ) δ 7.66 (d, J = 8.3 Hz, 2H), 7.37 (d, J = 8.0 Hz, 2H), 7.33 - 7.25 (m, 3H), 7.05 (dd, J = 7.5, 2.1 Hz, 2H), 6.24 (s, 1H), 6.01 (s, 1H), 5.48 (s, 1H), 3.26 - 3.07 (m, 2H), 3.07 - 2.97 (m, 2H), 2.38 (s, 3H), 1.37 (tt, J = 11.9, 5.8 Hz, 1H), 0.82 (dq, J = 11.6, 5.7 Hz, 1H). 13 13C NMR (100 MHz, DMSO-d 6 ) δ 167.0, 143.2, 139.7, 137.6, 129.7, 128.6, 128.3, 128.0, 127.1, 126.4, 61.3, 58.4, 43.6, 33.1, 21.1.

[0056] In a 1000 mL flask, to a dry DCM (560 mL) solution of Compound 4 (1.0 equiv) was added 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC·HCl, 1.2 equiv) and DMAP (1.2 equiv). After stirring at room temperature for 12 h, the solvent was removed under reduced pressure, and the residue was dissolved in ethyl acetate (20 mL). This organic layer was washed with 1 M aq. HCl (3 × 20 mL) and saturated brine (30 mL), and dried over Na 2 SO 4Dry and concentrate in vacuo. The crude product was purified by column chromatography to give M1 as a white solid (1.3 g, yield 63%). The structural formula of compound M1 is shown below. NMR characterization results: 1 H NMR(400MHz,CDCl 3 )δ7.72(d,J=8.2Hz,2H),7.31-7.20(m,5H),7.09-7.03(m,2H),6.06(s,1H),5.66(s,1H),5.60(s,1H),4.41(ddd,J=12.5,9.7,2.9Hz,1H),4.17(dt,J=12.2,4.6Hz,1H),3.80(dq,J=15.8,2.2Hz,1H),3.05-2.94(m,1H),2.42(s,3H),2.16(ddtd,J=15.3,12.6,4.8,3.1Hz,1H),1.77(tdd,J=11.9,6.8,3.5Hz,1H). 13 C NMR(100MHz,CDCl 3 )δ170.7,144.0,140.3,137.3,134.9,129.9,128.6,128.0,127.5,127.4,123.8,66.4,66.0,42.0,30.6,21.7.

[0057]

[0058] 2. Preparation of cycloallylamine monomer M2

[0059]

[0060] A mixed reactant of compound 1 (6.7 g, 20.0 mmol), N-(4-((tert-butyldimethylsilyloxy)oxy)butyl)-4-methylbenzenesulfonamide (7.1 g, 20.0 mmol) and DABCO (448 mg, 4.0 mmol) was placed in THF (100 mL) and stirred at room temperature for 2 h. After the reaction was completed, the solvent was evaporated under reduced pressure, and the residue was dissolved in ethyl acetate (30 mL). This organic layer was washed with 1M aq. HCl (3×20 mL) and saturated brine (30 mL), and dried with Na 2 SO 4 and then concentrated in vacuo. The crude product was purified by column chromatography to give colorless oily compound 5 (5.3 g, yield 46%). 1 HNMR(400MHz,CDCl 3)δ 7.69 (d, J = 8.3 Hz, 2H), 7.25 - 7.19 (m, 5H), 7.05 - 7.00 (m, 2H), 6.25 (s, 1H), 6.03 (s, 1H), 5.45 (s, 1H), 3.30 (td, J = 6.5, 2.2 Hz, 2H), 3.21 - 2.99 (m, 2H), 2.40 (s, 3H), 1.41 - 1.29 (m, 2H), 1.20 (s, 9H), 1.15 - 1.05 (m, 2H), 0.82 (s, 9H), -0.06 (s, 6H). 13 C NMR (100 MHz, CDCl 3 ) 165.2, 143.1, 140.8, 138.0, 137.9, 129.5, 128.5, 128.0, 127.4, 126.0, 81.3, 62.7, 62.1, 46.2, 30.2, 27.7, 27.1, 26.0, 21.6, 18.3, -5.3.

[0061] Compound 5 (5.3 g, 9.2 mmol) was dissolved in a solution of water (20 mL) and THF (20 mL), and acetic acid (60 mL) was added. The reaction mixture was stirred at room temperature for 12 h. After the reaction was completed, the solvent was removed under reduced pressure, and the residue was dissolved in ethyl acetate (30 mL). This organic layer was washed with saturated sodium bicarbonate solution (3 × 20 mL) and saturated brine (30 mL), and dried over Na 2 SO 4 and concentrated in vacuo to give a colorless oil. This colorless oil was dissolved in 1,4 - dioxane (14 mL), and then 6 M aq. HCl (14 mL) was added. The reaction mixture was refluxed at 90 °C for 1.5 h. After cooling to room temperature, the reaction mixture was diluted with water (50 mL) and extracted with ethyl acetate (2 × 50 mL). The organic layer was washed with saturated brine (3 × 50 mL), and dried over Na 2 SO 4 and concentrated in vacuo to give white solid compound 6 (3.5 g, yield 95%). 1 HNMR (400 MHz, CDCl 3)δ7.65(d, J = 8.0 Hz, 2H), 7.26 - 7.19(m, 5H), 7.03(dd, J = 6.6, 2.9 Hz, 2H), 6.42(s, 1H), 6.03(s, 1H), 5.64(s, 1H), 3.30(dt, J = 8.1, 4.0 Hz, 2H), 3.11(dddd, J = 39.0, 15.1, 10.7, 5.1 Hz, 2H), 2.39(s, 3H), 1.38(dp, J = 12.0, 6.1 Hz, 1H), 1.15(h, J = 7.1 Hz, 2H), 0.84(ddd, J = 19.2, 9.6, 5.3 Hz, 1H). 13 C NMR(100 MHz, CDCl 3 )δ170.1, 170.0, 143.4, 138.7, 137.5, 137.1, 129.6, 129.4, 128.7, 128.5, 128.2, 127.4, 61.9, 61.5, 46.2, 29.4, 26.7, 21.6.

[0062] A solution of 2-chloro-1-methylpyridinium iodide (CMPI, 8.8 g, 34.4 mmol) (860 mL) was added to DCM (60 mL). A solution of compound 6 (3.50 g, 8.6 mmol) and triethylamine (9.6 mL, 68.8 mmol) in DCM was added via an injection pump at 40 °C over 8 h. The reaction mixture was cooled to room temperature, filtered, and the solvent was removed under reduced pressure. The residue was dissolved in water (100 mL) and extracted with diethyl ether (3 × 30 mL). The organic phase was washed with saturated brine (30 mL). The combined organic layers were dried over Na 2 SO 4 and concentrated in vacuo. The crude product was purified by column chromatography to afford white solid compound M2 (1.3 g, 39% yield). NMR characterization results: 1 H NMR(400 MHz, CDCl 3) δ 7.79 (d, J = 8.3 Hz, 2H), 7.35 (d, J = 8.0 Hz, 2H), 7.25 - 7.17 (m, 3H), 6.90 (dd, J = 6.8, 2.9 Hz, 2H), 6.26 (s, 1H), 5.95 (s, 1H), 5.55 (s, 1H), 4.85 (ddd, J = 10.3, 6.1, 3.5 Hz, 1H), 3.81 (ddd, J = 11.3, 8.8, 2.9 Hz, 1H), 3.27 (dt, J = 15.2, 4.2 Hz, 1H), 2.87 (ddd, J = 15.1, 10.8, 4.0 Hz, 1H), 2.46 (s, 3H), 2.04 (dddt, J = 14.5, 10.7, 7.0, 3.7 Hz, 1H), 1.83 - 1.71 (m, 1H), 1.65 - 1.56 (m, 1H), 1.41 (dtt, J = 15.2, 6.1, 3.1 Hz, 1H). 13 C NMR (100 MHz, CDCl 3 ) δ 167.6, 143.8, 141.4, 137.3, 136.7, 129.9, 128.6, 128.4, 127.8, 127.7, 127.4, 67.0, 65.2, 48.1, 28.6, 25.9, 21.7.

[0063]

[0064] 3. Preparation of cycloallylamine monomer M3

[0065]

[0066] The reaction mixture of compound 1 (6.7 g, 20.0 mmol), N-(6-((tert-butyldimethylsilyloxy)oxy)hexyl)-4-methylbenzenesulfonamide (7.7 g, 20.0 mmol) and DABCO (448 mg, 4.0 mmol) in THF (100 mL) was stirred at room temperature for 2 h. After the reaction was completed, the solvent was evaporated under reduced pressure, and the residue was dissolved in ethyl acetate (30 mL). This organic layer was washed with 1M aq. HCl (3 × 20 mL) and saturated brine (30 mL), dried over Na 2 SO 4 and then concentrated in vacuo. The crude product was purified by column chromatography to give 7 (4.2 g, yield 35%) as a colorless oil. 1 H NMR (400 MHz, CDCl 3)δ 7.67 (d, J = 8.5 Hz, 2H), 7.23 - 7.17 (m, 5H), 7.04 - 6.99 (m, 2H), 6.23 (s, 1H), 6.04 (s, 1H), 5.41 (s, 1H), 3.45 (t, J = 6.5 Hz, 2H), 3.15 - 2.94 (m, 2H), 2.37 (s, 3H), 1.35 - 1.23 (m, 4H), 1.01 (p, J = 7.3 Hz, 2H), 0.90 (ddd, J = 12.8, 6.5, 2.1 Hz, 1H), 0.84 (s, 9H), 0.76 - 0.65 (m, 1H), -0.02 (s, 6H). 13 C NMR (100 MHz, CDCl 3 )δ 165.1, 143.0, 140.7, 137.9, 137.9, 129.4, 128.4, 127.8, 127.3, 126.0, 81.2, 62.9, 61.9, 46.1, 32.5, 30.0, 27.6, 26.5, 25.9, 25.0, 21.5, 18.3, -5.3.

[0067] To a solution of compound 7 (4.2 g, 7.0 mmol) in water (20 mL) and THF (20 mL) was added acetic acid (60 mL). The reaction mixture was stirred at room temperature for 12 h. After completion of the reaction, the solvent was removed under reduced pressure, and the residue was dissolved in ethyl acetate (30 mL). This organic layer was washed with saturated sodium bicarbonate solution (3 × 20 mL) and saturated brine (30 mL), dried over Na 2 SO 4 and then concentrated in vacuo to give a colorless oil. This colorless oil was dissolved in 1,4 - dioxane (11 mL), and then 6M aq. HCl (11 mL) was added. The reaction mixture was refluxed at 90 °C for 1.5 h. After cooling to room temperature, the reaction mixture was diluted with water (50 mL) and extracted with ethyl acetate (2 × 50 mL). The organic layer was washed with saturated brine (3 × 50 mL), dried over Na 2 SO 4 and then concentrated in vacuo to give white solid compound 8 (2.8 g, yield 93%). 1 H NMR (400 MHz, DMSO - d 6) δ 7.68 (d, J = 8.1 Hz, 2H), 7.40 - 7.27 (m, 5H), 7.05 (dd, J = 7.2, 2.4 Hz, 2H), 6.22 (s, 1H), 5.98 (s, 1H), 5.47 (s, 1H), 3.24 (t, J = 6.5 Hz, 2H), 3.07 (dddd, J = 56.0, 15.3, 10.9, 5.0 Hz, 2H), 2.39 (s, 3H), 1.16 (dq, J = 13.4, 6.8 Hz, 4H), 0.95 (q, J = 7.5 Hz, 2H), 0.88 - 0.76 (m, 2H). 13 C NMR (100 MHz, DMSO - d 6 ) δ 167.0, 143.2, 139.6, 137.6, 129.8, 128.7, 128.4, 128.0, 127.1, 126.3, 61.2, 60.6, 45.7, 32.3, 29.7, 26.0, 24.8, 21.1.

[0068] A solution of 2 - chloro - 1 - methylpyridinium iodide (CMPI, 6.6 g, 25.9 mmol) (650 mL) was added to DCM (50 mL), and a solution of the white solid compound 8 (2.8 g, 6.5 mmol) and triethylamine (7.2 mL, 51.9 mmol) in DCM was added via an injection pump at 40 °C for eight hours. The reaction mixture was cooled to room temperature, filtered, the solvent was removed under reduced pressure, the residue was dissolved in water (100 mL), and extracted with diethyl ether (3 × 30 mL). The combined organic layers were dried with Na 2 SO 4 and concentrated in vacuo. The crude product was purified by column chromatography to give the white solid M3 (295 mg, yield 11%). 1 1H NMR (400 MHz, CDCl 3 ) δ 7.65 (d, J = 8.3 Hz, 2H), 7.28 (dd, J = 32.0, 7.0 Hz, 7H), 6.63 (s, 1H), 5.77 (s, 1H), 5.62 (s, 1H), 4.35 (dt, J = 9.0, 2.9 Hz, 1H), 3.71 (td, J = 10.7, 2.0 Hz, 1H), 3.52 (ddd, J = 15.3, 9.7, 6.0 Hz, 1H), 3.24 (dt, J = 14.8, 5.0 Hz, 1H), 2.40 (s, 3H), 1.78 - 1.59 (m, 3H), 1.42 (pd, J = 11.5, 10.7, 4.1 Hz, 2H), 1.26 (dtd, J = 13.5, 7.0, 3.7 Hz, 1H), 1.09 - 0.98 (m, 1H), 0.93 - 0.80 (m, 1H). 1313C NMR (100 MHz, CDCl 3 ) δ 166.4, 143.2, 139.9, 138.5, 137.2, 133.3, 129.4, 128.4, 128.0, 127.7, 127.4, 66.0, 62.7, 47.2, 24.9, 24.7, 24.3, 23.7, 21.6.

[0069]

[0070] 4. Preparation of cycloallylamine monomer M4

[0071]

[0072] Acetic acid (60 mL) was added to a solution of compound 3 (5.6 g, 10 mmol) in water (20 mL) and THF (20 mL). The reaction mixture was stirred at room temperature for 12 h. After the reaction was completed, the solvent was removed under reduced pressure, and the residue was dissolved in ethyl acetate (30 mL). This organic layer was washed with saturated sodium bicarbonate solution (3 × 20 mL) and saturated brine (30 mL), dried over Na 2 SO 4 and then concentrated in vacuo to give compound 9 as a colorless oil (4.4 g, yield 98%). 1 1H NMR (400 MHz, CDCl 3 ) δ 7.64 (d, J = 8.3 Hz, 2H), 7.24 - 7.15 (m, 5H), 7.07 - 7.00 (m, 2H), 6.17 (s, 1H), 6.05 (s, 1H), 5.32 (s, 1H), 3.37 - 3.12 (m, 4H), 2.37 (s, 3H), 1.47 - 1.34 (m, 1H), 1.20 (s, 9H), 1.09 - 0.97 (m, 1H). 13 13C NMR (100 MHz, CDCl 3 ) δ 165.1, 143.3, 140.2, 137.7, 137.3, 129.5, 128.5, 128.5, 128.0, 127.3, 126.1, 81.4, 61.9, 59.7, 43.1, 33.1, 27.6, 21.5.

[0073] A mixture of compound 9 (4.4 g, 9.8 mmol), sulfonamide sequence (3.6 g, 10.8 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC·HCl, 2.3 g, 11.8 mmol) and DMAP (60 mg, 0.49 mmol) was stirred overnight at room temperature in DCM (100 mL). After the reaction, the solvent was evaporated under reduced pressure and the residue was dissolved in ethyl acetate (30 mL). This organic layer was washed with 1M aq. HCl (3×20 mL) and saturated brine (30 mL), and dried over Na 2 SO 4 and then concentrated in vacuo. The crude product was purified by column chromatography to give compound 10 as a colorless oil (5.6 g, 82% yield). 1 1H NMR (400 MHz, CDCl 3 ) δ 7.67 (d, J = 8.1 Hz, 2H), 7.26 - 7.18 (m, 5H), 7.03 (dd, J = 6.6, 2.9 Hz, 2H), 6.19 (s, 1H), 6.06 (s, 1H), 5.29 (s, 1H), 4.49 (s, 2H), 4.12 (t, J = 5.0 Hz, 2H), 3.81 - 3.73 (m, 4H), 3.16 (dddd, J = 74.3, 15.2, 10.9, 4.9 Hz, 2H), 2.74 - 2.62 (m, 4H), 2.39 (s, 3H), 1.75 - 1.61 (m, 1H), 1.19 (s, 9H), 1.03 (tt, J = 11.9, 5.8 Hz, 1H), 0.85 (s, 9H), 0.03 (s, 6H). 13 13C NMR (100 MHz, CDCl 3 ) δ 172.0, 171.6, 167.4, 165.0, 143.4, 140.3, 137.7, 137.4, 129.6, 128.6, 128.4, 128.1, 127.4, 125.9, 81.4, 66.0, 62.9, 61.9, 61.1, 60.7, 43.1, 29.4, 28.8, 28.6, 27.6, 25.8, 21.5, 18.3, -5.3.

[0074] Acetic acid (60 mL) was added to a solution of compound 10 (5.6 g, 8 mmol) in water (20 mL) and THF (20 mL). The reaction mixture was stirred at room temperature for 12 h. After completion of the reaction, the solvent was removed under reduced pressure and the residue was dissolved in ethyl acetate (30 mL). This organic layer was washed with saturated sodium bicarbonate solution (3×20 mL) and saturated brine (30 mL), and dried over Na 2 SO 4Dry and concentrate in vacuo to obtain a colorless oil. Dissolve this colorless oil in DCM (100 mL), then add trifluoroacetic acid (TFA, 2.9 mL, 37.1 mmol), and stir at room temperature for 2 h. Dilute the reaction mixture with toluene (50 mL) and concentrate in vacuo to obtain a white solid. Dissolve this white solid in a mixture of DCM (60 mL) and triethylamine (8.9 mL, 64 mmol), and add it dropwise to a refluxing solution of 2-chloro-1-methylpyridinium iodide (CMPI, 8.2 g, 32 mmol) in DCM (800 mL) over 8 h via an injection pump. Cool the reaction mixture to room temperature, filter, remove the solvent under reduced pressure, and dissolve the residue in water (100 mL). Extract with ether (3 × 30 mL). Combine the organic layers and wash with Na 2 SO 4 Dry and concentrate in vacuo. Purify the crude product by column chromatography to obtain the white solid compound M3 (230 mg, yield 5%). NMR characterization results: 1 1H NMR (400 MHz, CDCl 3 3) δ 7.58 (d, J = 8.3 Hz, 2H), 7.24 - 7.15 (m, 5H), 7.13 - 7.06 (m, 2H), 6.47 (s, 1H), 6.13 (s, 1H), 5.50 (s, 1H), 4.60 (d, J = 15.7 Hz, 1H), 4.45 - 4.17 (m, 6H), 3.86 (ddd, J = 11.2, 7.1, 4.0 Hz, 1H), 3.32 (qdd, J = 15.2, 10.7, 5.3 Hz, 2H), 2.80 - 2.71 (m, 2H), 2.67 - 2.62 (m, 2H), 2.39 (s, 3H), 1.77 (dddt, J = 14.3, 7.4, 3.6, 1.8 Hz, 1H), 1.63 - 1.51 (m, 1H). 13 13C NMR (100 MHz, CDCl 3 3) δ 171.7, 171.6, 167.5, 165.6, 143.3, 138.8, 137.9, 137.7, 130.4, 129.5, 128.5, 128.2, 127.8, 127.5, 63.0, 62.5, 62.4, 62.3, 61.0, 44.1, 30.0, 29.3, 29.0, 21.6.

[0075]

[0076] 5. Preparation of cycloallylamine monomer M5

[0077]

[0078] The reaction mixture of compound 1 (3.3 g, 10.0 mmol), N-(2-((tert-butyldimethylsilyloxy)oxy)ethyl)-4-methylbenzenesulfonamide (3.2 g, 10.0 mmol), and 1,4-diazabicyclo[2.2.2]octane (DABCO, 224 mg, 2.0 mmol) in THF (50 mL) was stirred at room temperature for 2 h. After completion of the reaction, the solvent was evaporated under reduced pressure, and the residue was dissolved in ethyl acetate (20 mL). The organic layer was washed with 1 M aqueous HCl (3 × 20 mL) and saturated brine (30 mL), and dried over Na 2 SO 4 and concentrated in vacuo. The crude product was purified by column chromatography to give compound 11 as a colorless oil (2.7 g, 50% yield). 1 1H NMR (400 MHz, CDCl 3 ) δ 7.69 (d, J = 8.3 Hz, 2H), 7.30 - 7.21 (m, 6H), 7.09 - 7.02 (m, 2H), 6.24 (s, 1H), 6.13 (s, 1H), 5.34 (d, J = 1.9 Hz, 1H), 3.37 - 3.09 (m, 4H), 2.42 (s, 3H), 1.25 (s, 9H).

[0079] Acetic acid (30 mL) was added to a solution of compound 11 (2.7 g, 5 mmol) in water (10 mL) and THF (10 mL). The reaction mixture was stirred at room temperature for 12 h. After completion of the reaction, the solvent was removed under reduced pressure, and the residue was dissolved in ethyl acetate (20 mL). The organic layer was washed with saturated sodium bicarbonate solution (3 × 20 mL) and saturated brine (30 mL), and dried over Na 2 SO 4 and concentrated in vacuo to give a colorless oil. This colorless oil was dissolved in 1,4-dioxane (9 mL), and then 6 M aq. HCl (9 mL) was added. The reaction mixture was refluxed at 90 °C for 1.5 h. After cooling to room temperature, the reaction mixture was diluted with water (50 mL) and extracted with ethyl acetate (2 × 50 mL). The organic layer was washed with saturated brine (3 × 50 mL), and dried over Na 2 SO 4 and concentrated in vacuo to give compound 12 as a white solid (1.8 g, 97% yield). 1 1H NMR (400 MHz, CDCl 3)δ 7.68 (d, J = 8.2 Hz, 2H), 7.28 - 7.25 (m, 5H), 7.06 (dd, J = 6.6, 3.0 Hz, 2H), 6.47 (s, 1H), 6.12 (s, 1H), 5.66 (s, 1H), 3.70 (s, 2H), 3.32 - 3.27 (m, 2H), 2.42 (s, 3H).

[0080] In a 1000 mL flask, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC·HCl, 1.2 equiv) and DMAP (1.2 equiv) were added to a dry DCM (560 mL) solution of compound 12 (1.0 equiv). After stirring at room temperature for 12 h, the solvent was removed under reduced pressure, and the residue was dissolved in ethyl acetate (20 mL). This organic layer was washed with 1 M aq. HCl (3 × 20 mL) and saturated brine (30 mL), dried over Na 2 SO 4 and concentrated in vacuo. The crude product was purified by column chromatography to give M5 as a white solid (1.0 g, 60% yield). The structural formula of compound M5 is shown below. NMR characterization results: 1 1H NMR (400 MHz, CDCl 3 )δ 7.68 (d, J = 7.8 Hz, 2H), 7.23 (dd, J = 25.8, 7.9 Hz, 7H), 6.10 (s, 1H), 6.03 (s, 1H), 5.76 (s, 1H), 4.00 (q, J = 4.6 Hz, 2H), 3.88 (dt, J = 16.5, 3.7 Hz, 1H), 3.29 (dt, J = 16.2, 4.9 Hz, 1H), 2.37 (s, 3H). 13 13C NMR (100 MHz, CDCl 3 )δ 170.1, 144.3, 140.5, 137.1, 135.1, 130.1, 129.2, 128.3, 127.3, 126.8, 67.8, 60.6, 44.0, 21.7.

[0081]

[0082] Preparation of 6-cycloallylamine monomer M6

[0083]

[0084] tert-Butyl acrylate (20.5 g, 160 mmol), DABCO (1.8 g, 16 mmol), and triethylamine (1.7 g, 16 mmol) were dissolved in THF (30 mL). Then, formaldehyde solution (20.8 g, 250 mmol) and water (15 mL) were added, and the mixture was stirred at room temperature for 3 h. Subsequently, the temperature was raised to 55 °C and the reaction was carried out for 24 h. After the reaction was completed, the solvent was removed under reduced pressure, and the residue was dissolved in ethyl acetate (20 mL). The organic layer was washed with 1 M aqueous HCl (3 × 20 mL) and brine (30 mL), and dried over Na 2 SO 4 and concentrated in vacuo. Then, it was dissolved in THF (50 mL) under an ice-water bath, phosphorus tribromide (5.9 mL) was added, and the mixture was gradually warmed to room temperature and reacted for 3 h. After the reaction was completed, the reaction was quenched by adding water first, and then it was dissolved in petroleum ether (30 mL). The organic layer was washed with water (3 × 20 mL) and saturated brine (30 mL), and dried over Na 2 SO 4 and concentrated in vacuo. The crude product was purified by column chromatography to obtain colorless oil 11 (17.7 g, 52% yield). 1 1H NMR (400 MHz, CDCl 3 ) δ 6.19 (s, 1H), 5.82 (s, 1H), 4.11 (s, 2H), 1.49 (s, 9H). 13 13C NMR (100 MHz, CDCl 3 ) δ 164.1, 139.1, 128.1, 81.8, 30.0, 28.2.

[0085] Compound 11 (2.4 g, 11 mmol) and N-(6-hydroxyhexyl)-4-methylbenzenesulfonamide (2.7 g, 10 mmol) were dissolved in dichloromethane (50 mL). Then, triethylamine (2.1 mL, 15 mmol) was added, and the reaction mixture was stirred overnight at room temperature. After the reaction was completed, the organic layer was washed with 1 M aqueous HCl (3 × 20 mL) and saturated brine (30 mL), and dried over Na 2 SO 4 and concentrated in vacuo. The crude product was purified by column chromatography to obtain colorless oil 12 (3.7 g, 90% yield). 1 1H NMR (400 MHz, CDCl 3)δ 7.66 - 7.60 (m, 2H), 7.24 (dd, J = 8.4, 2.8 Hz, 2H), 6.19 (s, 1H), 5.77 (s, 1H), 3.91 (s, 2H), 3.52 (q, J = 5.7 Hz, 2H), 3.04 (t, J = 6.8 Hz, 2H), 2.36 (s, 3H), 1.43 (s, 9H), 1.42 - 1.35 (m, 4H), 1.29 - 1.15 (m, 4H). 13 C NMR(100 MHz, CDCl 3 )δ 165.3, 143.3, 137.6, 136.8, 129.8, 127.2, 126.4, 81.4, 62.6, 49.2, 48.7, 32.6, 28.4, 28.1, 25.3, 21.5.

[0086] Dissolve this colorless oil 12 in 1,4 - dioxane (11 mL), then add 6M aq. HCl (11 mL). Reflux the reaction mixture at 90 °C for 1.5 h. After cooling to room temperature, dilute the reaction mixture with water (50 mL) and extract with ethyl acetate (2 × 50 mL). Wash the organic layer with saturated brine (3 × 50 mL), and dry with Na 2 SO 4 dry, and then concentrate in vacuo to obtain a white solid (3.1 g, yield 98%). Add a solution of 2 - chloro - 1 - methylpyridinium iodide (CMPI, 13.3 g, 52.2 mmol) in DCM (50 mL) to DCM (900 mL), and add a solution of the white solid (3.1 g, 8.7 mmol) and triethylamine (14.5 mL, 104 mmol) in DCM to it at 40 °C via an injection pump over eight hours. Cool the reaction mixture to room temperature, filter, remove the solvent under reduced pressure, dissolve the residue in water (100 mL), extract with diethyl ether (3 × 30 mL), and wash with saturated brine (30 mL). Dry the combined organic layers with Na 2 SO 4 dry, and concentrate in vacuo. Purify the crude product by column chromatography to obtain 5 as a white solid (320 mg, yield 11%).

[0087]

[0088] 1 H NMR(400 MHz, CDCl 3)δ 7.64 (d, J = 8.2 Hz, 2H), 7.30 (d, J = 7.9 Hz, 2H), 6.31 (s, 1H), 5.70 (s, 1H), 4.17 (dd, J = 6.2, 3.7 Hz, 2H), 3.71 (s, 2H), 3.10 (t, J = 5.7 Hz, 2H), 2.41 (s, 3H), 1.80 (dq, J = 9.6, 5.5 Hz, 2H), 1.58 (ddt, J = 32.5, 14.1, 6.2 Hz, 6H).

[0089] 13 C NMR (100 MHz, CDCl 3 ) δ 165.9, 143.5, 137.7, 135.0, 130.0, 129.7, 127.7, 66.1, 50.1, 49.5, 25.3, 24.0, 23.2, 23.2, 21.6.

[0090] Example Reaction Method:

[0091] This example provides an experimental method for Michael addition - ring - opening polymerization. The specific method is as follows: In a 3 - mL reaction flask, an initiator (0.004 mmol), a cycloallylamine monomer M1 or M2 or M3 or M4 or M5 (0.1 mmol), and DMF (1 mL) are added. The reaction is carried out at room temperature in air. After the reaction is completed, a small amount of dichloromethane is added, and precipitation is carried out with n - hexane twice. After vacuum drying, the corresponding polymers P1 or P2 or P3 or P4 or P5 are obtained, and GPC and NMR characterizations are performed.

[0092] Example 1 A nitrogen - containing polymer, its preparation method and application - Preparation of polymer P1

[0093] According to the above - mentioned experimental method of addition - ring - opening polymerization, using M1 (0.1 mmol) and Init2 (0.004 mmol) as reaction raw materials, the reaction is carried out at room temperature in air for 3 h to obtain polymer P1 (conversion rate > 99%, Mn = 8000, ). The structural formula of polymer P1 is shown as follows. The results of NMR characterization: 1 H NMR (400 MHz, CDCl 3 ) δ 7.64 (d, J = 8.2 Hz, 2H), 7.26 - 7.10 (m, 7H), 6.73 (s, 1H), 4.02 - 3.93 (m, 4H), 2.97 (dt, J = 10.0, 5.2 Hz, 2H), 2.37 (s, 3H), 1.76 (dq, J = 12.1, 6.3 Hz, 2H). 13 C NMR (100 MHz, CDCl 3)δ167.6,143.6,137.0,136.5,135.3,129.9,129.5,128.5,128.3,127.4,62.7,52.3,46.2,27.6,21.6.

[0094]

[0095] Example 2 A nitrogen-containing polymer, its preparation method and application - Preparation of polymer P2

[0096] According to the experimental method of the above addition-fragmentation ring-opening polymerization reaction, using M2 (0.1 mmol) and Init2 (0.004 mmol) as reaction raw materials, reacting at room temperature in air for 5 h to obtain polymer P2 (conversion rate > 99%, Mn = 9900, ). The structural formula of polymer P2 is shown as follows. NMR characterization results: 1 H NMR(400MHz,CDCl 3 )δ7.67(d,J = 8.1Hz,2H),7.28 - 7.23(m,5H),7.15(dd,J = 7.4,2.3Hz,2H),6.77(s,1H),4.03(s,2H),3.94(t,J = 5.9Hz,2H),3.08(t,J = 6.7Hz,2H),2.38(s,3H),1.40(p,J = 6.6,6.0Hz,4H). 13 C NMR(100MHz,CDCl 3 )δ167.9,143.5,136.9,135.3,129.9,129.5,128.5,128.4,128.3,127.4,64.6,51.6,48.3,25.5,24.7,21.6.

[0097]

[0098] Example 3 A nitrogen-containing polymer, its preparation method and application - Preparation of polymer P3

[0099] According to the experimental method of the above addition-fragmentation ring-opening polymerization reaction, using M3 (0.1 mmol) and Init2 (0.004 mmol) as reaction raw materials, reacting at room temperature in air for 2 h to obtain polymer P3 (conversion rate > 99%, Mn = 12500, ). The structural formula of polymer P2 is shown as follows. NMR characterization results: 1 H NMR(400MHz,CDCl 3) δ 7.69 (d, J = 8.1 Hz, 2H), 7.26 (d, J = 14.5 Hz, 5H), 7.17 (dd, J = 7.6, 2.0 Hz, 2H), 6.84 (s, 1H), 4.10 (s, 2H), 3.93 (t, J = 6.7 Hz, 2H), 3.13 (t, J = 7.7 Hz, 2H), 2.39 (s, 3H), 1.47 (q, J = 7.6 Hz, 2H), 1.37 (p, J = 6.9 Hz, 2H), 1.17 - 0.97 (m, 4H). 13 C NMR (100 MHz, CDCl 3 ) δ 168.1, 143.4, 137.1, 136.8, 135.5, 129.8, 129.7, 128.4, 128.4, 128.3, 127.4, 65.1, 51.4, 48.6, 28.2, 28.1, 26.5, 25.5, 21.6.

[0100]

[0101]

[0102] Example 4 A nitrogen-containing polymer, its preparation method and application

[0103] In this example, the conditions of the Michael addition-ring opening polymerization reaction in Example 3 were optimized.

[0104] 4.1 Optimization of the initiator type

[0105] Specific experimental method: The controlled anionic ring-opening polymerization reaction of the cycloallylamine monomer M1 was carried out using the polymerization reaction in Example 1. The selected initiators were Init1, Init2, Init3, Init4, Init5, Init6, and Init7. The monomer conversion rate, polymer molecular weight, and molecular weight distribution results finally obtained are shown in Table 1 and Figure 1 as follows. Among them, tetrahydrofuran was used as the mobile phase and polystyrene was used as the standard for GPC determination. It can be seen from Table 1 and Figure 1 that the polymerization reaction can be very well controlled when Init2 is used as the initiator, and a polymer with a number-average molecular weight of 7300 and a dispersity of 1.17 is generated, and the molecular weight is relatively close to the theoretical molecular weight.

[0106] Table 1

[0107]

[0108] 4.2 Optimization of the reaction solvent type

[0109] Specific experimental method: The controlled anionic polymerization reaction of cycloallylamine monomer M1 was carried out using the polymerization reaction of Example 1. DMF, DMSO, NMP, MeCN, THF, and 1,4-Dioxane were used as solvents in each group of reactions. The monomer conversion rate, polymer molecular weight, and molecular weight distribution results finally obtained are shown in Table 2 and Figure 2 as follows. In the GPC measurement, tetrahydrofuran was used as the mobile phase and polystyrene was used as the standard. From Table 2 and Figure 2 it can be seen that when DMF was used as the solvent, the reaction effect was the best, followed by DMSO. When toluene and THF were used as solvents, the reaction effect was relatively poor, which may be due to the poor solubility of the polymer in toluene and THF.

[0110] Table 2

[0111]

[0112] 4.3 Optimization of reaction concentration

[0113] Specific experimental method: The controlled anionic polymerization reaction of cycloallylamine monomer M1 was carried out using the polymerization reaction of Example 1. 0.05M, 0.1M, 0.2M, 0.4M, and 0.6M were used as reaction concentrations in each group of reactions. The monomer conversion rate, polymer molecular weight, and molecular weight distribution results finally obtained are shown in Table 3 and Figure 3 as follows. In the GPC measurement, tetrahydrofuran was used as the mobile phase and polystyrene was used as the standard. From Table 3 and Figure 3 it can be seen that when 0.1M was used as the reaction concentration, the reaction effect was the best.

[0114] Table 3

[0115]

[0116] Example 5

[0117] In this example, the Michael addition-ring opening polymerization reaction of Example 1 was used to prepare polymers with different molecular weights.

[0118] 5.1 Preparation of P1 with different molecular weights

[0119] Specific experimental method: The controlled radical ring opening polymerization reaction of cycloallylamine monomer M1 was carried out using the polymerization reaction of Example 1 to prepare P1 with different molecular weights. The molar ratios of monomer / initiator were selected as 10 / 1, 25 / 1, 50 / 1, and 100 / 1. The monomer conversion rate, polymer molecular weight, and molecular weight distribution results finally obtained are shown in Table 4 and Figure 4 as follows. In the GPC measurement, tetrahydrofuran was used as the mobile phase and polystyrene was used as the standard. From Table 4 and Figure 4It can be seen that by regulating the ratio of monomer to initiator, polymers P1 with molecular weights ranging from 3.9 thousand to 20 thousand can be prepared, and the molecular weight distribution is basically in the range of 1.06 - 1.09.

[0120] Table 4

[0121]

[0122] 5.2 Preparation of P2 with Different Molecular Weights

[0123] Specific experimental method: The controlled anionic ring-opening polymerization reaction of cycloallylamine monomer M2 was carried out using the polymerization reaction of Example 2 to prepare P2 with different molecular weights. The molar ratios of monomer to initiator were selected as 10 / 1, 25 / 1, 50 / 1, and 100 / 1. The final monomer conversion rates, polymer molecular weights, and molecular weight distribution results are shown in Table 5 and Figure 5 as follows. In the GPC measurement, tetrahydrofuran was used as the mobile phase and polystyrene was used as the standard. From Table 5 and Figure 5 it can be seen that by regulating the ratio of monomer to initiator, polymers P2 with molecular weights ranging from 4.6 thousand to 23 thousand can be prepared, and the molecular weight distribution is basically in the range of 1.09 - 1.20.

[0124] Table 5

[0125]

[0126]

[0127] 5.3 Preparation of P3 with Different Molecular Weights

[0128] Specific experimental method: The controlled anionic ring-opening polymerization reaction of cycloallylamine monomer M3 was carried out using the polymerization reaction of Example 3 to prepare P3 with different molecular weights. The molar ratios of monomer to initiator were selected as 10 / 1, 25 / 1, 50 / 1, and 100 / 1. The final monomer conversion rates, polymer molecular weights, and molecular weight distribution results are shown in Table 6 and Figure 6 as follows. In the GPC measurement, tetrahydrofuran was used as the mobile phase and polystyrene was used as the standard. From Table 6 and Figure 6 it can be seen that by regulating the ratio of monomer to initiator, polymers P3 with molecular weights ranging from 5.5 thousand to 29 thousand can be prepared, and the molecular weight distribution is basically in the range of 1.06 - 1.10.

[0129] Table 6

[0130]

[0131] 5.4 Preparation of P4 with Different Molecular Weights

[0132] Preparation of polymers with an ester-functional sequence in the main chain.

[0133] Specific experimental method: The ring allylamine monomer M4 was subjected to a controlled anionic ring-opening polymerization reaction by using the addition-fragmentation polymerization reaction of the example. The final experimental results are as Figure 11 shown, and a polymer P4 (Mn = 10800, ) containing an ester-functional sequence in the main chain can be prepared. The structural formula of the polymer P4 is as follows. NMR characterization results: 1 H NMR (400 MHz, CDCl3) δ 7.86 (s, 0.51), 7.70 (d, J = 8.2 Hz, 1H), 7.52 (d, J = 8.0 Hz, 1H), 7.46 - 7.35 (m, 3H), 7.33 - 7.27 (m, 2H), 7.25 - 7.18 (m, 2H), 6.86 (s, 0.49), 4.61 - 4.50 (m, 2H), 4.35 (s, 2H), 4.26 - 4.19 (m, 2H), 4.17 - 4.06 (m, 3H), 4.00 (q, J = 5.7 Hz, 1H), 3.27 - 3.18 (m, 1H), 3.01 (d, J = 7.6 Hz, 1H), 2.79 - 2.63 (m, 3H), 2.57 (t, J = 6.9 Hz, 1H), 2.40 (d, J = 7.3 Hz, 3H), 1.93 (pt, J = 6.2, 2.8 Hz, 1H), 1.71 (dqd, J = 8.8, 6.1, 2.6 Hz, 1H). 13 C NMR (100 MHz, CDCl3) δ 172.0, 171.9, 171.8, 167.7, 167.6, 167.5, 167.2, 144.6, 143.8, 143.6, 137.9, 136.4, 135.4, 134.9, 134.2, 130.0, 129.9, 129.8, 129.6, 128.9, 128.9, 128.8, 128.5, 128.4, 127.6, 127.5, 127.4, 63.1, 62.9, 62.8, 62.7, 62.5, 62.2, 60.9, 52.5, 45.8, 45.7, 44.8, 28.9, 28.8, 28.7, 28.7, 28.2, 27.9, 21.6.

[0134]

[0135] 5.5 Preparation of Polymer P5

[0136] According to the experimental method of the above addition-fragmentation ring-opening polymerization reaction, using M5 (0.1 mmol) and Init2 (0.004 mmol) as reaction raw materials, reacting at room temperature in air for 12 h, polymer P5 was obtained (conversion rate 89%, Mn = 6200, )。The structural formula of polymer P5 is as follows. NMR characterization results: 1 H NMR(400MHz,CDCl3)δ7.66-7.58(m,2H),7.18(d,J=3.1Hz,5H),6.70(d,J=8.8Hz,1H),4.16-4.07(m,3H),3.93(s,2H),3.27(q,J=6.9Hz,2H),3.12-2.96(m,1H),2.34(s,3H).

[0137]

[0138] Example 6

[0139] In this example, the addition-fragmentation ring-opening polymerization reaction of Example 1 was studied kinetically and block copolymers were prepared.

[0140] 6.1 Kinetic study

[0141] 1H NMR was used to monitor the addition-fragmentation ring-opening polymerization reaction of Example 1. Samples were taken at reaction times of 20 min, 40 min, 60 min, 80 min, 100 min, and 120 min for 1H NMR tests to calculate the conversion rate, and GPC tests were performed to calculate the molecular weight and dispersity of the polymer. The final experimental results are as Figure 7 and Figure 8 shown. As can be seen from Figure 7 , the polymerization reaction exhibits first-order kinetic behavior. As can be seen from Figure 8 , there is a linear relationship between the polymer molecular weight and the monomer conversion rate, and the dispersity is basically maintained below 1.1. Based on the above experimental results, it shows that this polymerization reaction is a controlled polymerization reaction.

[0142] 6.2 Preparation of block copolymers.

[0143] Specific experimental method: First, the controlled anionic ring-opening polymerization reaction of cycloallylamine monomer M1 was carried out using the addition-fragmentation ring-opening polymerization reaction of Example 1 to prepare a macromolecular initiator P1 with a moderate molecular weight. Then, monomer M2 was used for chain extension. The final experimental results are as Figure 9 shown. From the GPC characterization results of Figure 10 , it can be seen that compared with the first block polymer P1 (Mn = 8100, ), the GPC curve of the obtained diblock copolymer P1-b-P2 (Mn = 16600, ) shifted significantly towards the high molecular weight direction. The block copolymer P1-b-P2 means that P1 is first synthesized and then polymerized with monomer M2 to form the P1 and P2 block copolymer, where b is block. The structural formula of P1-b-P2 is as follows. NMR characterization results:1 H NMR (400 MHz, CDCl 3 ) δ 7.65 (dd, J = 12.1, 8.2 Hz, 4H), 7.27 - 7.14 (m, 14H), 6.77 (s, 1H), 6.73 (s, 1H), 4.03 (s, 2H), 3.96 (dq, J = 10.1, 5.9 Hz, 6H), 3.08 (t, J = 6.9 Hz, 2H), 2.97 (dd, J = 9.1, 6.3 Hz, 2H), 2.38 (d, J = 2.9 Hz, 6H), 1.76 (dd, J = 8.9, 5.8 Hz, 2H), 1.40 (t, J = 5.6 Hz, 4H). The experimental results show that this polymerization method has important application prospects in the synthesis of multi-block polymers.

[0144]

[0145] Example 7

[0146] Sodium methoxide degradation experiment

[0147] Specific experimental method: In a 3 ml sample bottle, add polymer P1 (10 mg) and THF (1 ml), then add a methanol solution of 35 wt% sodium methoxide (10 μl), and stir the solution at room temperature. Take 100 μl of the reaction mixture at different time intervals (1 min, 10 min, 20 min), add 5 μL of 6 M aqueous hydrochloric acid solution to quench, and then conduct GPC testing. Subsequently, collect all the reaction solutions, extract the mixture with 2 mL of DCM, concentrate under vacuum, and finally purify the crude product directly by flash column chromatography to obtain the degradation product 13. 1 H NMR (400 MHz, CDCl 3 ) δ 7.73 (d, J = 8.0 Hz, 2H), 7.31 (d, J = 9.5 Hz, 5H), 7.22 - 7.14 (m, 2H), 6.81 (s, 1H), 4.13 (s, 2H), 3.72 (d, J = 10.1 Hz, 2H), 3.61 (s, 3H), 3.35 (d, J = 6.6 Hz, 2H), 2.43 (s, 3H), 1.80 (p, J = 6.1 Hz, 2H). It can be seen from the GPC curve that the molecular weight of the polymer can be completely degraded within 20 min, and the generation of the degradation product can be proved by NMR. The results of these characterizations all show that the obtained polymer has good degradation performance and can be completely degraded into small molecule fragments in a short time under alkaline conditions, and it is a kind of biodegradable polymer material with good application prospects in the medical field and the biotechnology field.

[0148]

[0149] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A method for preparing a nitrogen-containing polymer, characterized in that: The cycloallylamine monomer, initiator and organic solvent are reacted under air at room temperature; The cycloallylamine monomer includes one of M1, M2, M3, M4 or M5: The general structural formula of the nitrogen-containing polymer is as follows: Wherein, R is a group of any of the following structures: Wherein, --- indicates the substitution position; n does not exceed 100.

2. The method for preparing a nitrogen-containing polymer according to claim 1, characterized in that: The structure of the nitrogen-containing polymer is P1, P2, P3, P4 or P5:

3. The method for preparing a nitrogen-containing polymer according to claim 1, characterized in that: The structure of the initiator includes one or more of Init1, Init2, Init3, Init4, Init5 or Init6:

4. The method for preparing a nitrogen-containing polymer according to claim 1, characterized in that: The number average molecular weight of the nitrogen-containing polymer is 0.39 to 29,500.

5. The method for preparing a nitrogen-containing polymer according to claim 1, characterized in that: The dispersity of the nitrogen-containing polymer is 1.0 to 1.

2.

6. The method for preparing a nitrogen-containing polymer according to claim 1, characterized in that: The molar ratio of the cycloallylamine monomer to the initiator is 10:1 to 100:

1.

7. The method for preparing a nitrogen-containing polymer according to claim 1, characterized in that: The concentration of the cycloallylamine monomer is 0.05M to 0.6M.

8. The method for preparing a nitrogen-containing polymer according to claim 1, characterized in that: The organic solvent is selected from one or more of N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone or acetonitrile.

9. The method for preparing a nitrogen-containing polymer according to claim 1, characterized in that: The reaction time of the addition-fragmentation ring-opening polymerization reaction is 2 to 24 hours.

10. A nitrogen-containing polymer, characterized in that Its general structure is as follows: Wherein, R is a group having any of the following structures: Wherein, --- indicates the substitution position; n does not exceed 100.

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