Boron-nitrogen polymers and methods for their preparation

Abstract

The application discloses a kind of boron-nitrogen polymers and preparation method thereof, belong to the field of polymer materials.A kind of boron-nitrogen polymer, with formula I shown in structural formula:Wherein, R1It is selected from hydrogen, alkyl, aryl, heteroaryl one;Ar 1 , Ar 2 It is independently selected from aryl, heteroaryl one;Boron-nitrogen ring is five-membered ring or six-membered ring.The polymer prepared in the application has novel structure and diversification and multifunctionality.The method of the application is a new polymerization reaction, which is directly generated from boronic acid compound and arylamine under dehydration in solvent to form polymer, the substrate of the method is strong in applicability, and the process is simple, raw material is cheap, the condition is mild, and the reaction is efficient.

Description

Technical Field

[0001] This application relates to a class of boron-nitrogen polymers and their preparation methods, belonging to the field of polymer materials. Background Technology

[0002] In recent years, replacing C=C double bonds with boron-nitrogen (BN) single bonds has been an effective strategy for enriching and innovating organic materials. Therefore, research on using this strategy to regulate material properties has received widespread attention. Boron atoms can be considered isoelectronic of carbocations, and nitrogen atoms can be considered isoelectronic of carbanions. When one boron atom and one nitrogen atom replace two carbon atoms respectively, an isoelectronic all-carbon molecule is obtained. Since the total number of valence electrons remains unchanged, the new compound exhibits certain similarities in properties to its all-carbon isoelectronic counterpart. However, because the boron-nitrogen bond forms a boron-nitrogen dipole within the molecule, the charge distribution at various positions is no longer uniform. Therefore, it also affects molecular properties, including electron cloud distribution, optical properties, and redox potential, thus showing potential application value in multiple fields such as materials science, biomedicine, catalysis, and organic synthesis.

[0003] In recent years, numerous scientists have conducted research on boron-nitrogen compounds, synthesizing various types of boron-nitrogen heterocyclic compounds, including 1,2-boron-nitrogen heterocyclic fused ring compounds, 1,3-boron-nitrogen heterocyclic fused ring compounds, and 1,4-boron-nitrogen heterocyclic fused ring compounds, etc. Studies have shown that these boron-nitrogen heterocyclic fused ring compounds possess excellent photoelectric properties. Although significant progress has been made in the performance research of boron-nitrogen heterocyclic fused ring compounds in recent years, research on polymers with boron-nitrogen heterocyclic conjugated skeletons remains very limited. This is because a suitable polymerization method for synthesizing such polymers has not yet been developed. The development of new polymerization reactions has always been of great significance to polymer research and is a scientific issue of widespread interest to polymer scientists. Therefore, developing a new polymerization method to prepare boron-nitrogen polymers with novel structures is of great importance for the research of boron-nitrogen polymer materials. Summary of the Invention

[0004] According to a first aspect of this application, a boron-nitrogen polymer is provided, which has a novel and diverse structure and possesses the functions of a conjugated polymer.

[0005] DD221030I

[0006] A boron-nitrogen polymer having the structural formula shown in Formula I:

[0007]

[0008] R1 is selected from one of hydrogen, alkyl, aryl, and heteroaryl groups;

[0009] Ar 1 Ar2 It is independently selected from one of aryl and heteroaryl groups;

[0010] The boron-nitrogen ring is a five-membered or six-membered ring.

[0011] Optionally, R1 is selected from C1 to C20 alkyl groups;

[0012] R1 is selected from C6 to C12 aryl groups;

[0013] R1 is selected from C4 to C12 heteroaryl groups.

[0014] Optionally, the heteroatom in the heteroaryl group is selected from at least one of oxygen, nitrogen, and sulfur;

[0015] Optionally, Ar 1 Ar 2 Aryl groups independently selected from C6 to C30;

[0016] Ar 1 Ar 2 Independently selected from heteroaryl groups of C4–C30;

[0017] The heteroatom in the heteroaryl group is selected from at least one of oxygen, nitrogen, and sulfur.

[0018] Optionally, the mass-average molecular weight of the boron-nitrogen polymer is 5,000 to 30,000.

[0019] Optionally, the mass-average molecular weight of the boron-nitrogen polymer is independently selected from any value or a range between any two of the following: 5000, 6000, 7000, 8000, 8500, 8700, 9000, 9200, 9500, 10000, 11000, 12100, 13000, 14000, 15300, 16500, 17600, 18000, 20000, 25000, and 30000.

[0020] Alternatively, the structural formula shown in Equation I is as follows:

[0021]

[0022] According to a second aspect of this application, a method for preparing boron-nitrogen polymers is provided. This method involves the direct reaction of amines and boric acid to construct nitrogen-boron bonds for polymerization, thereby achieving the preparation of novel boron-nitrogen conjugated polymers. This provides a convenient synthetic method for a large class of novel polymers rich in boron-nitrogen structures. This method is applicable to various types of amine and boric acid monomers, and the prepared polymers have novel structures that are difficult to obtain using conventional polymerization methods. It greatly enriches the types of monomers for polymers, expands the range of polymer types, and produces diverse product structures with wide applicability. The synthesis process is simple, requires no metal catalysts, has mild reaction conditions, is easy to operate, and is highly efficient.

[0023] A method for preparing a boron-nitrogen polymer includes the following steps:

[0024] A mixture containing boric acid compounds, amine compounds, and solvents is reacted to obtain the boron-nitrogen polymer.

[0025] Optionally, the boric acid compound is selected from compounds having the structural formula shown in Formula II:

[0026]

[0027] Optionally, the amine compound is selected from compounds having the structural formula shown in Formula III:

[0028] DD221030I

[0029]

[0030] Optionally, the solvent is selected from at least one of 1,4-dioxane, ethylene glycol dimethyl ether, tetrahydrofuran, toluene, benzene, cyclopentyl methyl ether, and methyl tert-butyl ether.

[0031] Optionally, the molar ratio of the boric acid compound to the amine compound is 0.5:1 to 2:1.

[0032] Optionally, the molar ratio of the boric acid compound to the amine compound is independently selected from any value or a range between 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1.0:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, and 2.0:1.

[0033] Optionally, the ratio of the volume of the solvent to the molar number of the boric acid compound is 1 mL / mmol to 10 mL / mmol.

[0034] Optionally, the ratio of the volume of the solvent to the molar number of the boric acid compound is independently selected from any value or a range between any two of 1 mL / mmol, 1.5 mL / mmol, 2 mL / mmol, 2.5 mL / mmol, 3 mL / mmol, 3.5 mL / mmol, 4 mL / mmol, 4.5 mL / mmol, 5 mL / mmol, 5.5 mL / mmol, 6 mL / mmol, 6.5 mL / mmol, 7 mL / mmol, 7.5 mL / mmol, 8 mL / mmol, 8.5 mL / mmol, 9 mL / mmol, 9.5 mL / mmol, and 10 mL / mmol.

[0035] Alternatively, the reaction conditions are as follows:

[0036] The temperature ranges from 50℃ to 150℃.

[0037] The time period is from 18 hours to 96 hours.

[0038] Optionally, the temperature is independently selected from any value or a range between 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, and 150°C.

[0039] Optionally, the time is independently selected from any value or a range between any two of 18h, 20h, 22h, 24h, 26h, 28h, 30h, 32h, 35h, 37h, 40h, 42h, 45h, 47h, 50h, 52h, 55h, 57h, 60h, 62h, 65h, 67h, 70h, 72h, 75h, 77h, 80h, 82h, 85h, 87h, 90h, and 96h.

[0040] Optionally, post-processing is also included.

[0041] Optionally, the post-processing includes diluting the polymerization reaction solution obtained from the reaction with a diluent and precipitating it with a precipitant.

[0042] Optionally, the diluent is selected from at least one of 1,4-dioxane, tetrahydrofuran, and ethyl acetate.

[0043] Optionally, the precipitant is selected from at least one of methanol, ethanol, propanol, acetone, petroleum ether, n-hexane, and diethyl ether.

[0044] The beneficial effects that this application can produce include:

[0045] 1) The boron-nitrogen polymer provided in this application has a novel and diverse structure and possesses the function of conjugated polymerization.

[0046] 2) The present application provides a method for preparing a boron-nitrogen polymer, which is to prepare a novel boron-nitrogen polymer by directly constructing carbon-boron bonds and polymerizing it. The polymer prepared is difficult to obtain by other traditional polymerization methods and is a new type of polymerization reaction.

[0047] 3) The boron-nitrogen polymer preparation method provided in this application has broad substrate applicability, which can greatly enrich the types of polymer monomers and expand the types of polymers, and has a wide range of applications.

[0048] 4) The method for preparing boron-nitrogen polymer provided in this application has a simple synthesis process, does not require a metal catalyst, has mild reaction conditions, is easy to operate, and has high reaction efficiency. Detailed Implementation

[0049] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0050] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.

[0051] The analysis method in this application embodiment is as follows:

[0052] Nuclear magnetic resonance (NMR) measurements were performed on a Bruker 400AVANCE III NMR spectrometer or a NECZ600R from NEC.

[0053] Molecular weight was determined using an Agilent 1260 Infinity II gel permeation chromatograph.

[0054] The yield calculation in this embodiment is as follows:

[0055] Yield % = (Actual mass of target product obtained ÷ Theoretically expected mass of target product) × 100%.

[0056] Example 1

[0057]

[0058] In this embodiment, the raw materials, process, conditions, and results of the reaction are as shown above.

[0059] Amine (278 mg, 1 mmol) and boric acid (165 mg, 1 mmol) were added to a sealed tube equipped with a magnetic stirrer, followed by 3 mL of 1,4-dioxane solvent. The mixture was then placed in an oil bath at 110 °C and reacted for 60 hours. After the reaction was completed, the mixture was cooled to room temperature, precipitated in petroleum ether, and finally dried in a vacuum drying oven to obtain polymer product sample 1, with a yield of 85%.

[0060] The detection data of the proton and carbon NMR spectra of product sample 1 are as follows:

[0061] 1 H NMR (400MHz, DMSO-d6) δ (ppm): 9.84-9.50 (broad, 4H), 7.98-7.82 (broad, 4H), 7.61-7.50 (broad, 2H), 7.48-7.36 (broad, 2H), 7.27-7.13 (broad, 2H).

[0062] 13 C NMR (151MHz, DMSO-d6) δ (ppm): 141.50, 137.64, 134.14, 133.60, 133.54, 133.48, 133.02, 132.76, 118.97, 111.31, 109.71.

[0063] The mass-average molecular weight is 12,100.

[0064] Example 2

[0065]

[0066] In this embodiment, the raw materials, process, conditions, and results of the reaction are as shown above.

[0067] Amine (278 mg, 1 mmol) and boric acid (241 mg, 1 mmol) were added to a sealed tube equipped with a magnetic stirrer, followed by 2 mL of tetrahydrofuran solvent. The mixture was then placed in an oil bath at 130 °C and reacted for 90 hours. After the reaction was completed, the mixture was cooled to room temperature, precipitated in petroleum ether, and finally dried in a vacuum drying oven to obtain polymer product sample 2, with a yield of 90%.

[0068] The detection data of the proton and carbon NMR spectra of product sample 2 are as follows:

[0069] DD221030I

[0070] 1 H NMR (400MHz, DMSO-d6) δ (ppm): 9.93-9.46 (broad, 4H), 8.17-7.68 (broad, 9H), 7.58-7.41 (broad, 3H), 7.30-7.09 (broad, 2H).

[0071] 13 C NMR (101MHz, DMSO-d6) δ (ppm): 141.64, 141.48, 137.63, 135.26, 134.64, 132.68, 126.79, 126.11, 118.89, 111.19, 109.61.

[0072] The mass-average molecular weight is 15,300.

[0073] Example 3

[0074]

[0075] In this embodiment, the raw materials, process, conditions, and results of the reaction are as shown above.

[0076] Amine (278 mg, 1 mmol) and boric acid (281 mg, 1 mmol) were added to a sealed tube equipped with a magnetic stirrer, followed by 8 mL of ethylene glycol dimethyl ether solvent. The mixture was then placed in an oil bath at 90 °C and reacted for 30 hours. After the reaction was completed, the mixture was cooled to room temperature, precipitated in petroleum ether, and finally dried in a vacuum drying oven to obtain polymer product sample 3, with a yield of 78%.

[0077] The detection data of the proton and carbon NMR spectra of product sample 3 are as follows:

[0078] 1 H NMR(400MHz, DMSO-d6)δ(ppm):9.88-9.47(broad,4H),8.20-8.04(broad,2H),8.02-7.35(broad,4H),7.66-7.33(broad,4H),7.29-7.11(broad,2H),.

[0079] 13 C NMR (101MHz, DMSO-d6) δ (ppm): 153.54, 141.60, 140.67, 137.75, 133.12, 132.70, 128.31, 120.69, 118.93, 111.17, 109.58, 46.81, 27.67.

[0080] The mass-average molecular weight is 9200.

[0081] Example 4

[0082]

[0083] In this embodiment, the raw materials, process, conditions, and results of the reaction are as shown above.

[0084] Amine (278 mg, 1 mmol) and boric acid (271 mg, 1 mmol) were added to a sealed tube equipped with a magnetic stirrer, followed by 6 mL of 1,4-dioxane solvent. The mixture was then placed in an oil bath at 110 °C and reacted for 50 hours. After the reaction was completed, the mixture was cooled to room temperature, precipitated in petroleum ether, and finally dried in a vacuum drying oven to obtain polymer product sample 4, with a yield of 89%.

[0085] The detection data of the proton and carbon NMR spectra of product sample 4 are as follows:

[0086] 1 H NMR (400MHz, DMSO-d6) δ (ppm): 9.96-9.45 (broad, 4H), 8.41-8.19 (broad, 2H), 8.09-7.93 (broad, 2H), 7.92-7.68 (broad, 4H), 7.61-7.28 (broad, 4H).

[0087] 13 C NMR (151MHz, DMSO-d6) δ (ppm): 159.55, 141.40, 137.91, 133.76, 133.35, 123.68, 123.49, 119.03, 115.30, 111.43, 110.54.

[0088] The mass-average molecular weight is 16,500.

[0089] Example 5

[0090]

[0091] In this embodiment, the raw materials, process, conditions, and results of the reaction are as shown above.

[0092] Amine (278 mg, 1 mmol) and boric acid (255 mg, 1 mmol) were added to a sealed tube equipped with a magnetic stirrer, followed by 10 mL of 1,4-dioxane solvent. The mixture was then placed in an oil bath at 110 °C and reacted for 60 hours. After the reaction was completed, the mixture was cooled to room temperature, precipitated in petroleum ether, and finally dried in a vacuum drying oven to obtain polymer product sample 5, with a yield of 93%.

[0093] The detection data of the proton and carbon NMR spectra of product sample 5 are as follows:

[0094] 1 H NMR(400MHz, DMSO-d6)δ(ppm):9.96-9.59(broad,4H),8.33-8.16(broad,2H),8.05-7.91(broad,2H),7.87-7.60(broad,4H),7.56-7.32(broad,4H).

[0095] 13 C NMR (101MHz, DMSO-d6) δ (ppm): 159.56, 141.39, 133.77, 133.34, 123.67, 123.49, 119.03, 111.42, 110.53.

[0096] The mass-average molecular weight is 8700.

[0097] Example 6

[0098]

[0099] In this embodiment, the raw materials, process, conditions, and results of the reaction are as shown above.

[0100] Amine (314 mg, 1 mmol) and boric acid (165 mg, 1 mmol) were added to a sealed tube equipped with a magnetic stirrer, followed by 5 mL of 1,4-dioxane solvent. The mixture was then placed in an oil bath at 110 °C and reacted for 60 hours. After the reaction was completed, the mixture was cooled to room temperature, precipitated in petroleum ether, and finally dried in a vacuum drying oven to obtain polymer product sample 6, with a yield of 92%.

[0101] The detection data of the proton and carbon NMR spectra of product sample 6 are as follows:

[0102] 1 H NMR (400MHz, DMSO-d6) δ (ppm): 8.66-8.26 (broad, 4H), 8.15-7.86 (broad, 4H), 8.05-7. 91(broad,2H),7.14-6.89(broad,4H),6.84-6.58(broad,4H),6.48-6.36(broad,2H).

[0103] 13 C NMR (151MHz, DMSO-d6) δ (ppm): 143.11, 142.16, 135.40, 133.83, 132.47, 132.20, 129.65, 127.91, 120.24, 115.51, 106.26, 106.14.

[0104] The mass-average molecular weight is 17,600.

[0105] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A boron-nitrogen polymer, characterized in that, It has the structural formula shown in Equation I: Formula I; R1 is selected from one of hydrogen, alkyl, aryl, and heteroaryl groups.

2. The boron-nitrogen polymer according to claim 1, characterized in that, R1 is selected from C1 to C20 alkyl groups.

3. The boron-nitrogen polymer according to claim 1, characterized in that, The boron-nitrogen polymer has a mass-average molecular weight of 5,000 to 30,000.

4. The method for preparing the boron-nitrogen polymer according to any one of claims 1 to 3, characterized in that, Includes the following steps: A mixture containing boric acid compounds, amine compounds, and solvents is reacted to obtain the boron-nitrogen polymer. The boric acid compound is selected from one of the compounds having the structural formula shown in Formula II: Formula II; The amine compound is selected from one of the compounds having the structural formula shown in Formula III: Formula III; Ar 1 Ar 2 Selected from aryl and heteroaryl groups corresponding to those in Formula I; The molar ratio of the boric acid compound to the amine compound is 0.5:1 to 2:1; The ratio of the volume of the solvent to the molar number of the boric acid compound is 1 mL / mmol to 10 mL / mmol; The reaction conditions are as follows: The temperature ranges from 50°C to 150°C. The time frame is 18 h to 96 h.

5. The preparation method according to claim 4, characterized in that, The solvent is selected from at least one of 1,4-dioxane, ethylene glycol dimethyl ether, tetrahydrofuran, toluene, benzene, cyclopentyl methyl ether, and methyl tert-butyl ether.

6. The preparation method according to claim 4, characterized in that, It also includes post-processing.

7. The preparation method according to claim 6, characterized in that, The post-processing includes diluting the polymerization reaction solution obtained from the reaction with a diluent and precipitating it with a precipitant.

8. The preparation method according to claim 7, characterized in that, The diluent is selected from at least one of 1,4-dioxane, tetrahydrofuran, and ethyl acetate.

9. The preparation method according to claim 7, characterized in that, The precipitant is selected from at least one of methanol, ethanol, propanol, acetone, petroleum ether, n-hexane, and diethyl ether.

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