A triazine derivative, process for its preparation and use thereof

Abstract

This invention provides a triazine derivative having the structure shown in formula (1). This invention also provides a method for preparing the triazine derivative and its uses. The triazine derivative provided by this invention has a novel structure and is very suitable as a new type of leather tanning agent, achieving excellent tanning effects. Moreover, it eliminates the need for chromium powder, making it green and environmentally friendly, which is conducive to the transformation of the leather industry towards cleaner production. The triazine derivative provided by this invention uses inexpensive and readily available aniline derivatives, sulfonyl lactones, and trihalomycins as raw materials. The preparation process is simple, the reaction conditions are mild, the purification process is easy, and the yield of the target product is high. Therefore, it has strong industrial applicability and is suitable for large-scale production and application.

Description

Technical Field

[0001] This invention relates to the field of leather tanning, specifically to a triazine derivative and its preparation method, and also to the use of the triazine derivative as a leather tanning agent. Background Technology

[0002] Currently, chrome tanning holds a dominant position in the leather industry. However, the absorption rate of chrome tanning agents is typically low, resulting in high-concentration chromium-containing wastewater and significant losses of chrome tanning agents. This not only increases environmental pollution and wastewater treatment costs but also represents a substantial waste of resources. Due to the adverse environmental impact of chromium pollutants, the leather industry has been classified as a highly polluting industry. Therefore, researching green and environmentally friendly chrome-free tanning agents to replace the current chrome tanning method and reduce environmental pollution in the leather industry has become a widely concerned issue in the leather academia and industry in recent years, and a crucial problem that urgently needs to be solved to ensure the sustainable development of the leather industry.

[0003] In recent years, some new types of chromium-free tanning agents have emerged, such as aluminum tanning agents, titanium tanning agents, iron tanning agents, zirconium tanning agents, rare earth tanning agents, vegetable tanning agents, and aldehyde tanning agents. Organic chromium-free tanning agents are also an important branch of chromium-free tanning agents. Chinese patent CN116083659A discloses a glycerol triglycidyl ether modified oligochitosan-based organic chromium-free tanning agent. Using glycerol triglycidyl ether and oligochitosan as raw materials, the preparation of an organic chromium-free tanning agent has been achieved. Leather tanned with this agent has higher shrinkage temperature, physical and mechanical properties, and water resistance. In addition, leather tanned with this agent also has excellent antibacterial properties and resistance to yellowing. Chinese patent CN 115011742A discloses an epoxy-modified collagen polypeptide-based organic chromium-free tanning agent. It uses collagen polypeptide and glycidyl ether with a polyepoxy structure as the main raw materials. The collagen polypeptide is modified by the glycidyl ether with a polyepoxy structure, and the organic chromium-free tanning agent is prepared by catalysis. This can solve the problem of water and soil pollution caused by acid washing and the use of neutral salts in the application of tanning agents in the prior art, and can also maintain the physicochemical properties of tanned leather.

[0004] It is evident that organic chromium-free tanning agents possess excellent properties and can achieve good tanning results; therefore, it is necessary to further develop more types of organic chromium-free tanning agents. Summary of the Invention

[0005] To overcome the shortcomings of the existing technology, one object of the present invention is to provide a triazine derivative with a novel structure, which, as a new type of chromium-free leather tanning agent, can achieve excellent tanning effect.

[0006] Another object of the present invention is to provide a method for preparing the triazine derivatives.

[0007] Another object of the present invention is to provide the use of the triazine derivatives.

[0008] The first aspect of the present invention provides a triazine derivative having a structure as shown in formula (1).

[0009]

[0010] Wherein, R represents a C1-C6 alkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkyl group, a halogen, or a hydroxyl group;

[0011] m represents an integer from 2 to 8 (including integers of 1, 2, 3, 4, 5, 6, 7 or 8);

[0012] n represents an integer from 1 to 4 (inclusive of 1, 2, 3, or 4). When n is not 1, each R may be the same or different.

[0013] X represents F or Cl.

[0014] In some preferred embodiments, R can be the same or different, and can each independently represent methyl, ethyl, n-propyl, isopropyl, methoxy, ethoxy, trifluoromethyl, trichloromethyl, F, Cl, Br or hydroxyl.

[0015] In some preferred embodiments, the triazine derivative may further have a structure as shown in formula (1-1) or formula (1-2).

[0016]

[0017] In this context, R1 and R2 each independently represent a C1-C4 alkyl group, a C1-C4 alkoxy group, a C1-C4 haloalkyl group, a halogen, or a hydroxyl group.

[0018] In some preferred embodiments, R1 and R2 each independently represent methyl, ethyl, n-propyl, isopropyl, methoxy, ethoxy, trifluoromethyl, trichloromethyl, F, Cl, Br or hydroxyl;

[0019] m represents an integer from 2 to 6;

[0020] X represents F or Cl.

[0021] In some further preferred embodiments, R1 represents methyl, ethyl, n-propyl, isopropyl, methoxy, trifluoromethyl, or hydroxy;

[0022] R2 represents F or Cl;

[0023] m represents 3 or 4;

[0024] X represents Cl.

[0025] In some preferred embodiments, the triazine derivative is selected from the following compounds:

[0026]

[0027]

[0028] A second aspect of the present invention provides a method for preparing the triazine derivative having the structure shown in formula (1), comprising the following steps:

[0029] S1: The aniline derivative with the structure shown in formula (2-1) is reacted with a sulfonate lactone with the structure shown in formula (2-2) to prepare an aniline sulfonic acid intermediate with the structure shown in formula (2-3); and

[0030] S2: The aniline sulfonic acid intermediate is reacted with a trihalomycin with the structure shown in formula (2-4) to prepare the triazine derivative;

[0031]

[0032] Wherein, R, m, n, and X are as defined in any of the above technical solutions.

[0033] In the preparation method provided by the present invention, the aniline derivative, sulfonyl lactone, and trihalomethanetriazine can be common commercially available products, or they can be prepared in-house based on existing technologies in the field.

[0034] In some preferred embodiments, the aniline derivatives include, but are not limited to: 2-methylaniline (CAS Registry No. 62-53-3), 3-chloro-2-methylaniline (CAS Registry No. 87-60-5), 3-bromo-2-methylaniline (CAS Registry No. 55289-36-6), 3-fluoro-2-methylaniline (CAS Registry No. 443-86-7), 4-chloro-2-methylaniline (CAS Registry No. 95-69-2), 4-bromo-2-methylaniline (CAS Registry No. 583-75-5), 4-fluoro-2-methylaniline (CAS Registry No. 451-71-1), 5-chloro-2-methylaniline (CAS Registry No. 451-71-1), and 3-methylaniline (CAS Registry No. 451-71-1). Aniline (CAS Registry No. 95-79-4), 5-bromo-2-methylaniline (CAS Registry No. 39478-78-9), 5-fluoro-2-methylaniline (CAS Registry No. 367-29-3), 6-chloro-2-methylaniline (CAS Registry No. 87-63-8), 6-bromo-2-methylaniline (CAS Registry No. 53848-17-2), 2-fluoro-6-methylaniline (CAS Registry No. 443-89-0), 3-methylaniline (CAS Registry No. 108-44-1), 3-trifluoromethylaniline (CAS Registry No. 98-16-8), 3-trifluoromethoxyani ... CAS No. 1535-73-5), 4-chloro-3-methylaniline (CAS No. 7149-75-9), 4-bromo-3-methylaniline (CAS No. 6933-10-4), 4-fluoro-3-methylaniline (CAS No. 452-69-7), 4-methylaniline (CAS No. 106-49-0), 2-chloro-4-methylaniline (CAS No. 615-65-6), 2-bromo-4-methylaniline (CAS No. 583-68-6), 2-fluoro-4-methylaniline (CAS No. 452-80-2), 3-chloro-4-methylaniline (CAS No. 95) -74-9), 3-bromo-4-methylaniline (CAS Registry No. 7745-91-7), 3-fluoro-4-methylaniline (CAS Registry No. 452-77-7), 3-chloro-5-methylaniline (CAS Registry No. 29027-20-1), 3-bromo-5-methylaniline (CAS Registry No. 74586-53-1), 3-fluoro-5-methylaniline (CAS Registry No. 52215-41-5), 2-hydroxyaniline (CAS Registry No. 95-55-6), 3-hydroxyaniline (CAS Registry No. 591-27-5), 4-hydroxyaniline (CAS Registry No. 123-30-8), etc.

[0035] In some preferred embodiments, the sulfonyl lactone includes, but is not limited to, 1,3-propanesulfonyl lactone (CAS Registry No. 1120-71-4), 1,4-butanesulfonyl lactone (CAS Registry No. 1633-83-6), etc.

[0036] In some preferred embodiments, the trihalomycin includes, but is not limited to, cyanuric chloride (CAS Registry No. 108-77-0) and cyanuric fluoride (CAS Registry No. 675-14-9).

[0037] In the preparation method provided by the present invention, in step S1, the aniline derivative and the sulfonyl lactone are reacted in an aprotic organic solvent at 30–120°C (for example, it can be about 30°C, about 40°C, about 50°C, about 60°C, about 70°C, about 80°C, about 90°C, about 100°C, about 110°C, about 120°C, or any combination of temperature ranges) for 2–12 hours (for example, it can be about 2 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 7 hours, about 8 hours, about 9 hours, about 10 hours, about 11 hours, about 12 hours, or any combination of time ranges) to prepare the aniline sulfonic acid intermediate.

[0038] In some preferred embodiments, the aprotic organic solvent may be selected from low-polarity aprotic organic solvents, including but not limited to one or more of dichloromethane, 1,2-dichloroethane, petroleum ether, n-hexane, cyclohexane, and 1,4-dioxane.

[0039] In some preferred embodiments, the molar ratio of the aniline derivative to the sulfonyl lactone can be 1:0.9 to 1.

[0040] In the preparation method provided by the present invention, in step S2, the aniline sulfonic acid intermediate and the trihalomycin are reacted in the presence of a surfactant and an acid-binding agent at 10–30°C (for example, a temperature range of about 10°C, about 12°C, about 15°C, about 18°C, about 20°C, about 22°C, about 25°C, about 30°C, or any combination thereof) for 2–10 h (for example, a time range of about 2 h, about 3 h, about 4 h, about 5 h, about 6 h, about 7 h, about 8 h, about 9 h, about 10 h, or any combination thereof) to prepare the triazine derivative.

[0041] In some preferred embodiments, the surfactant may be selected from nonionic surfactants, including but not limited to one or more of fatty alcohols (C10-C18), polyoxyethylene ethers (AEO, such as AEO-10, AEO-3), polyethylene glycol (PEG, such as PEG400-2000), and polypropylene glycol (PPG, such as PPG400-2000).

[0042] In some preferred embodiments, the acid-binding agent may be selected from common inorganic or organic bases, such as an aqueous solution of potassium hydroxide or sodium hydroxide with a concentration of 5–25 wt%. In some more preferred embodiments, the acid-binding agent may be selected from an aqueous solution of potassium hydroxide or sodium hydroxide with a concentration of 5–15 wt%.

[0043] In some preferred embodiments, in step S2, the molar ratio of the trihalomycin to the aniline sulfonic acid intermediate can be 1:0.8 to 1.

[0044] In some preferred embodiments, in step S2, the molar ratio of the trihalomycin to the surfactant can be 1:0.005 to 0.015 (for example, it can be about 1:0.005, about 1:0.008, about 1:0.01, about 1:0.012, about 1:0.015, or any combination of molar ratios).

[0045] In some preferred embodiments, in step S2, the acid-binding agent adjusts the pH of the reaction system to 5.0–7.5. In some more preferred embodiments, the acid-binding agent adjusts the pH of the reaction system to 6.0–6.5.

[0046] A third aspect of the present invention provides the use of the triazine derivatives described in any of the above-mentioned technical solutions as leather tanning agents.

[0047] The triazine derivatives provided by this invention contain multiple functional groups, including a triazine ring, a sulfonic acid group, and halogen atoms. The active halogen atoms on the triazine ring can condense with hydroxyl and amino groups in collagen to form stable covalent bonds, while the sulfonic acid group can form ionic bonds with amino groups on collagen fibers. This enables multi-point cross-linking between collagen fibers, resulting in excellent tanning effects. Therefore, the triazine derivatives provided by this invention are highly suitable as a novel leather tanning agent.

[0048] In some preferred embodiments, the leather tanning agent can be used in the leather tanning process where the raw hide is cowhide, buffalo hide, yak hide or goatskin.

[0049] In some preferred embodiments, the leather tanning agent can be used in the main leather tanning process.

[0050] The technical solution provided by this invention has the following advantages:

[0051] (1) The triazine derivatives provided by the present invention have novel structures, a variety of functional groups and high functionality, and can form multi-point cross-links between collagen fibers, thereby producing a tanning effect. Therefore, they are very suitable as a new type of leather tanning agent.

[0052] (2) The triazine derivatives provided by the present invention use inexpensive and readily available aniline derivatives, sulfonyl lactones and trihalomycins as raw materials. The preparation process is simple, the reaction conditions are mild, the purification process is simple, and the yield of the target product is high. Therefore, it has strong industrial applicability and is suitable for large-scale production and application.

[0053] (3) The triazine derivatives provided by this invention can achieve excellent tanning effect as leather tanning agents, significantly improve the moisture and heat resistance and physical and mechanical properties of leather collagen, and do not require the use of chromium powder, thus avoiding the pollution of the environment by metallic chromium. It is green, environmentally friendly, and conducive to the transformation of the leather industry to clean production. Therefore, it has great economic and social significance. Detailed Implementation

[0054] the term

[0055] As used herein, "C1-Cn" includes C1-C2, C1-C3, ..., C1-Cn. For example, the term "C1-C6" refers to a group having 1 to 6 carbon atoms, meaning the group contains 1, 2, 3, 4, 5, or 6 carbon atoms. Therefore, for example, "C1-C4 alkyl" refers to an alkyl group containing 1 to 4 carbon atoms, where the alkyl group is selected from methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl. Numerical ranges, such as "1-6," refer to integers within a given range.

[0056] The term "alkyl" as used alone or in combination herein refers to a saturated aliphatic hydrocarbon that is optionally substituted with a straight chain or optionally substituted with a branched chain. "alkyl" as used herein preferably has 1 to 6 carbon atoms, for example, 1 to 6 carbon atoms, or 1 to 5 carbon atoms, or 1 to 4 carbon atoms, or 1 to 3 carbon atoms. Non-limiting examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, 2-methyl-1-propyl, 2-methyl-2-propyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-3-butyl, 2,2-dimethyl-1-propyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl-2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2,2-dimethyl-1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, and hexyl. When the group defined in this article, such as "alkyl", has a numerical range, for example, "C1 to C6 alkyl" means an alkyl group that can be composed of 1, 2, 3, 4, 5 or 6 carbon atoms. The term alkyl in this article also includes cases where no numerical range is specified.

[0057] The term "alkyl" as used in this article refers to an alkyl group linked to other groups, such as alkoxy or haloalkyl groups, and is defined in the same way as when used alone.

[0058] The term "alkoxy" as used alone or in combination herein refers to an alkyl ether group, denoted as "alkyl-O-". Non-limiting examples of alkoxy groups include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, etc.

[0059] The term “halogen” as used alone or in combination in this article refers to fluorine, chlorine, bromine or iodine.

[0060] The term "haloalkyl" as used alone or in combination herein refers to an alkyl group in which one or more, or even all, of the hydrogen atoms are replaced by a halogen. Non-limiting examples of haloalkyl groups include trifluoromethyl, trichloromethyl, etc.

[0061] The technical solution of the present invention will be further described in detail below with reference to specific embodiments.

[0062] Unless otherwise specified, all raw materials or reagents used in the embodiments of the present invention are commercially available products.

[0063] Unless otherwise specified, all percentages used in the embodiments of the present invention are mass percentages.

[0064] Example 1

[0065] 260 mL of dichloromethane was added to a 500 mL four-necked flask, followed by 0.05 mol of 4-methylaniline and 0.05 mol of propanesulfonate lactone. The mixture was stirred and refluxed for 4 h. After cooling, the mixture was filtered to obtain a white solid, which is 3-(4-methylphenyl)amino-1-propanesulfonic acid. The structural formula of the product is as follows:

[0066]

[0067] 3-(4-methylphenyl)amino-1-propanesulfonic acid (C 10 H 15 NO3S)

[0068] 1 H NMR(400MHz,D2O): 6.88ppm(d,2H,CH3- C6H4 -NH-), 6.35ppm (d, 2H, CH3-) C6H4 -NH-), 6.13ppm(t,1H,- NH -CH2CH2CH2SO3H),3.45ppm(t,2H,-NHCH2CH2 CH2 SO3H), 3.09ppm (m,2H,-NH) CH2CH2CH2SO3H), 2.42ppm (s, 3H, CH3 -C6H4-NH-),2.12ppm(m,2H,-NHCH2 CH2 CH2SO3H).

[0069] 0.5 mol of cyanuric chloride, 3.2 g of AEO-10, and 500 mL of deionized water were added to a 1000 mL four-necked flask equipped with a stirrer and thermometer. The temperature was adjusted to 10–15 °C in an ice-water bath. 0.49 mol of 3-(4-methylphenyl)amino-1-propanesulfonic acid was added in four portions, with the addition completed in approximately 90 min. The reaction was stirred for 5 h, during which 10 wt% KOH solution was continuously added dropwise to adjust the pH to 6.0–6.5. After the reaction was completed, the mixture was filtered, and the crude product was purified by recrystallization from methanol to obtain N-(4,6-dichloro-1,3,5-triazin-2-yl)-4-methyl-aniline-1-propanesulfonic acid (yields shown in Table 1). The structural formula of the product is as follows:

[0070]

[0071] N-(4,6-dichloro-1,3,5-triazin-2-yl)-4-methyl-aniline-1-propanesulfonic acid (C 13 H 14 Cl2N4O3S)

[0072] 1 H NMR(400MHz,DMSO-d6): 11.52ppm(s,1H,- SO3H ), 6.89ppm (d, 2H, CH3- C6H4 -N-), 6.35ppm (d,2H,CH3-) C6H4 -N-), 3.45ppm(t,2H,-NCH2CH2) CH2 SO3H), 3.09ppm (t, 2H, -N) CH2 CH2CH2SO3H), 2.42ppm (s, 3H, CH3 -C6H4-N-), 2.10ppm(m,2H,-NCH2) CH2 CH2SO3H).

[0073] Example 2

[0074] Add 60 mL of dichloromethane to a 200 mL four-necked flask, then add 0.03 mol of 4-methylaniline and 0.03 mol of butanesulfonate lactone. Stir and reflux for 4 h. Cool and filter to obtain a white solid, which is 4-(4-methylphenyl)amino-1-butanesulfonic acid. The structural formula of the product is as follows:

[0075]

[0076] 4-(4-methylphenyl)amino-1-butanesulfonic acid (C 11 H 17 NO3S)

[0077] 1 H NMR(400MHz,D2O): 6.85ppm(d,2H,CH3- C6H4 -NH-), 6.33ppm (d, 2H, CH3-) C6H4 -NH-), 6.13ppm(t,1H,- NH -CH2CH2CH2CH2-SO3H),3.45ppm(t,2H,-NHCH2CH2CH2 CH2 SO3H), 3.09ppm (m,2H,-NH) CH2 CH2CH2CH2SO3H), 2.42ppm(s,3H, CH3 -C6H4-NH-),1.98ppm(m,2H,NHCH2CH2 CH2 CH2SO3H), 1.67ppm (m,2H,-NHCH2) CH2 CH2CH2SO3H).

[0078] 0.3 mol of cyanuric chloride, 2.8 g of AEO-3, and 500 mL of deionized water were added to a 1000 mL four-necked flask equipped with a stirrer and thermometer. The temperature was adjusted to 12–18 °C in an ice-water bath. 0.29 mol of 4-(4-methylphenyl)amino-1-butanesulfonic acid was added in four portions, with the addition completed over approximately 60 min. The reaction was stirred for 5 h, during which 10 wt% KOH solution was continuously added dropwise to adjust the pH to 6.0–6.5. After the reaction was completed, the mixture was filtered, and the crude product was purified by recrystallization from methanol to obtain N-(4,6-dichloro-1,3,5-triazin-2-yl)-4-methyl-aniline-1-butanesulfonic acid (yields shown in Table 1). The structural formula of the product is as follows:

[0079]

[0080] N-(4,6-dichloro-1,3,5-triazin-2-yl)-4-methyl-aniline-1-butanesulfonic acid (C 14 H 16 Cl2N4O3S)

[0081] 1 H NMR(400MHz,DMSO-d6): 11.66ppm(s,1H,- SO3H ), 6.92ppm (d, 2H, CH3- C6H4-N-), 6.38ppm (d,2H,CH3-) C6H4 -N-), 3.45ppm(t,2H,-NCH2CH2CH2) CH2 SO3H), 3.09ppm (m, 2H, -N) CH2 CH2CH2CH2SO3H), 2.42ppm(s,3H, CH3 -C6H4-N-),1.97ppm(m,2H,-NCH2CH2 CH2 CH2SO3H), 1.63ppm (m,2H,-NCH2) CH2 CH2CH2SO3H).

[0082] Example 3

[0083] Add 60 mL of dichloromethane to a 200 mL four-necked flask, then add 0.03 mol of 2-chloro-4-methylaniline (CAS Registry No. 615-65-6) and 0.03 mol of propanesulfonate lactone. Stir and reflux for 4 h. Cool and filter to obtain a white solid, which is 3-(2-chloro-4-methyl-phenyl)amino-1-propanesulfonic acid. The structural formula of the product is as follows:

[0084]

[0085] 3-(2-chloro-4-methyl-phenyl)amino-1-propanesulfonic acid (C 10 H 14 NClO3S, D2O)

[0086] 1 H NMR(400MHz,D2O): 6.92ppm(s,1H,CH3-C- CH (Cl)CC-NH-),6.73ppm(d,1H,CH3-C- CH CH-C-NH-),6.32ppm(d,1H,CH3-C-CH CH -C-NH-), 6.13ppm(t,1H,- NH CH2CH2CH2SO3H),3.42ppm(t,2H,-NHCH2CH2 CH2 SO3H), 3.07ppm (m,2H,-NH) CH2 CH2CH2SO3H), 2.38ppm (s, 3H, CH3 -C6H4-NH-),2.10ppm(m,2H,-NHCH2 CH2 CH2SO3H).

[0087] In a 1000 mL four-necked flask equipped with a stirrer and thermometer, 0.3 mol of cyanuric chloride, 3.0 g of AEO-3, and 500 mL of deionized water were added. The temperature was adjusted to 10–15 °C in an ice-water bath. 0.29 mol of 3-(2-chloro-4-methyl-phenyl)amino-1-propanesulfonic acid was added in four portions, with the addition completed over approximately 60 min. The reaction was continued for 3 h, during which 10 wt% NaOH solution was continuously added dropwise to adjust the pH to 6. After the reaction was complete, the mixture was filtered, and the crude product was purified by recrystallization from methanol to obtain N-(4,6-dichloro-1,3,5-triazin-2-yl)-2-chloro-4-methyl-aniline-1-propanesulfonic acid (yields shown in Table 1). The structural formula of the product is as follows:

[0088]

[0089] N-(4,6-dichloro-1,3,5-triazin-2-yl)-2-chloro-4-methylaniline-1-propanesulfonic acid (C 13 H 13 Cl3N4O3S)

[0090] 1 H NMR(400MHz,DMSO-d6): 11.56ppm(s,1H,- SO3H ), 6.98ppm(s, 1H, CH3-C- CH (Cl)CCN-), 6.79ppm (d, 1H, CH3-C-) CH CH-CN-), 6.38ppm (d, 1H, CH3-C-CH) CH -CN-), 3.45ppm(t,2H,-NHCH2CH2) CH2 SO3H), 3.10ppm (m,2H,-N) CH2 CH2CH2SO3H), 2.41ppm (s, 3H, CH3 -C6H4-N-), 2.13ppm(m,2H,-NCH2) CH2 CH2SO3H).

[0091] Example 4

[0092] Add 60 mL of dichloromethane to a 100 mL four-necked flask, then add 0.03 mol of 2-chloro-4-methylaniline (CAS Registry No. 615-65-6) and 0.03 mol of butanesulfonate lactone. Stir and reflux for 4 h. Cool and filter to obtain a white solid, which is 4-(2-chloro-4-methylphenyl)amino-1-butanesulfonic acid. The structural formula of the product is as follows:

[0093]

[0094] 4-(2-chloro-4-methylphenyl)amino-1-butanesulfonic acid (C 11 H 16 NClO3S, D2O)

[0095] 1 H NMR(400MHz,D2O): 6.89ppm(s,1H,CH3-C- CH (Cl)CC-NH-),6.70ppm(d,1H,CH3-C- CH CH-C-NH-),6.29ppm(d,1H,CH3-C-CH CH -C-NH-), 6.11ppm(t,1H,- NH -CH2CH2CH2CH2-SO3H),3.43ppm(t,2H,-NHCH2CH2CH2 CH2 SO3H), 3.10ppm (m,2H,-NH) CH2 CH2CH2CH2SO3H), 2.45ppm (s, 3H, CH3 -C6H4-NH-),2.01ppm(m,2H,NHCH2CH2 CH2 CH2SO3H), 1.65ppm (m,2H,-NHCH2) CH2 CH2CH2SO3H).

[0096] In a 1000 mL four-necked flask equipped with a stirrer and thermometer, 0.3 mol of cyanuric chloride, 2.8 g of AEO-3, and 500 mL of deionized water were added. The temperature was adjusted to 10–15 °C in an ice-water bath. 0.29 mol of 4-(2-chloro-4-methylphenyl)amino-1-butanesulfonic acid was added in four portions, with the addition completed over approximately 60 minutes. The reaction was continued for 4 hours, during which 10 wt% KOH solution was continuously added dropwise to adjust the pH to 6. After the reaction was complete, the mixture was filtered, and the crude product was purified by recrystallization from methanol to obtain N-(4,6-dichloro-1,3,5-triazin-2-yl)-2-chloro-4-methylaniline-1-butanesulfonic acid (yields shown in Table 1). The structural formula of the product is as follows:

[0097]

[0098] N-(4,6-dichloro-1,3,5-triazin-2-yl)-2-chloro-4-methylaniline-1-butanesulfonic acid (C 14 H 15 Cl3N4O3S)

[0099] 1 H NMR(400MHz,DMSO-d6): 11.72ppm(s,1H,- SO3H ), 6.89ppm(s, 1H, CH3-C- CH (Cl)CCN-), 6.72ppm (d, 1H, CH3-C-) CH CH-CN-), 6.33ppm (d, 1H, CH3-C-CH) CH -CN-),3.47ppm(t,2H,-NCH2CH2CH2 CH2 SO3H), 3.10ppm (m,2H,-N) CH2 CH2CH2CH2SO3H), 2.45ppm (s, 3H, CH3 -C6H4-N-),1.99ppm(m,2H,-NCH2CH2 CH2 CH2SO3H), 1.66ppm (m,2H,-NCH2) CH2 CH2CH2SO3H).

[0100] Example 5

[0101] Add 60 mL of dichloromethane to a 100 mL four-necked flask, then add 0.03 mol of 4-hydroxyaniline (CAS Registry No. 123-30-8) and 0.03 mol of propanesulfonate lactone. Stir and reflux for 4 h. Cool and filter to obtain a white solid, which is 3-(4-hydroxyphenyl)amino-1-propanesulfonic acid. The structural formula of the product is as follows:

[0102]

[0103] 3-(4-hydroxyphenyl)amino-1-propanesulfonic acid (C9H 13 NO4S, D2O)

[0104] 1 H NMR(400MHz,D2O): 6.53ppm(d,2H,CH3- C6H4 -NH-), 6.30ppm (d,2H,CH3-) C6H4 -NH-), 6.23ppm(s, 1H, COUGH -C6H4-NH-), 6.08ppm(t,1H,- NH -CH2CH2CH2SO3H),3.42ppm(t,2H,-NHCH2CH2 CH2 SO3H), 3.07ppm (m,2H,-NH) CH2 CH2CH2SO3H),2.09ppm(m,2H,-NHCH2 CH2 CH2SO3H).

[0105] In a 1000 mL four-necked flask equipped with a stirrer and thermometer, 0.3 mol of cyanuric chloride, 2.8 g of AEO-3, and 500 mL of deionized water were added. The temperature was adjusted to 10–13 °C in an ice-water bath. 0.29 mol of 3-(4-hydroxyphenyl)amino-1-propanesulfonic acid was added in four portions over approximately 60 minutes. The reaction was continued for 4 hours, during which 10 wt% KOH solution was continuously added dropwise to adjust the pH to 6. After the reaction was complete, the mixture was filtered, and the crude product was purified by recrystallization from methanol to obtain N-(4,6-dichloro-1,3,5-triazin-2-yl)-4-hydroxy-aniline-amino-1-propanesulfonic acid (yields shown in Table 1). The structural formula of the product is as follows:

[0106]

[0107] N-(4,6-dichloro-1,3,5-triazin-2-yl)-4-hydroxy-aniline-amino-1-propanesulfonic acid (C 12 H 12 Cl2N4O4S)

[0108] 1 H NMR(400MHz,DMSO-d6): 11.56ppm(s,1H,- SO3H ), 6.57ppm (d, 2H, CH3- C6H4 -N-), 6.33ppm (d,2H,CH3-) C6H4 -N-), 6.19ppm(s,1H, COUGH -C6H4-N-),3.45ppm(t,2H,-NCH2CH2 CH2 SO3H), 3.09ppm (m, 2H, -N) CH2 CH2CH2SO3H),2.11ppm(m,2H,-NCH2 CH2 CH2SO3H).

[0109] Example 6

[0110] Add 60 mL of dichloromethane to a 200 mL four-necked flask, then add 0.03 mol of 4-hydroxyaniline (CAS Registry No. 123-30-8) and 0.03 mol of butanesulfonate lactone. Stir and reflux for 4 h. Cool and filter to obtain a white solid, which is 4-(4-hydroxyphenyl)amino-1-butanesulfonic acid. The structural formula of the product is as follows:

[0111]

[0112] 4-(4-hydroxyphenyl)amino-1-butanesulfonic acid (C 10 H 15 NO4S)

[0113] 1 H NMR(400MHz,D2O): 6.82ppm(d,2H,CH3- C6H4 -NH-), 6.35ppm (d, 2H, CH3-) C6H4 -NH-), 6.23ppm(s, 1H, COUGH -C6H4-NH-), 6.11ppm(t,1H,- NH -CH2CH2CH2CH2-SO3H),3.45ppm(t,2H,-NHCH2CH2CH2 CH2 SO3H), 3.07ppm (m,2H,-NH) CH2 CH2CH2CH2SO3H),1.95ppm(m,2H,NHCH2CH2 CH2 CH2SO3H), 1.63ppm (m,2H,-NHCH2) CH2 CH2CH2SO3H).

[0114] In a 1000 mL four-necked flask equipped with a stirrer and thermometer, 0.3 mol of cyanuric chloride, 2.8 g of AEO-3, and 500 mL of deionized water were added. The temperature was adjusted to 12–15 °C in an ice-water bath. 0.29 mol of 4-(4-hydroxyphenyl)amino-1-butanesulfonic acid was added in four portions over approximately 60 minutes. The reaction was continued for 4 hours, during which 10 wt% KOH solution was continuously added dropwise to adjust the pH to 6. After the reaction was complete, the mixture was filtered, and the crude product was purified by recrystallization from methanol to obtain N-(4,6-dichloro-1,3,5-triazin-2-yl)-4-hydroxy-aniline-1-butanesulfonic acid (yields shown in Table 1). The structural formula of the product is as follows:

[0115]

[0116] N-(4,6-dichloro-1,3,5-triazin-2-yl)-4-hydroxyaniline-1-butanesulfonic acid (C 13 H 14 Cl2N4O4S)

[0117] 1 H NMR(400MHz,DMSO-d6): 11.52ppm(s,1H,- SO3H ), 6.80ppm (d, 2H, CH3- C6H4 -N-), 6.33ppm (d,2H,CH3-) C6H4 -N-), 6.25ppm(s,1H, COUGH -C6H4-N-),3.43ppm(t,2H,-NCH2CH2CH2 CH2SO3H), 3.08ppm (m, 2H, -N) CH2 CH2CH2CH2SO3H),1.93ppm(m,2H,-NCH2CH2 CH2 CH2SO3H), 1.67ppm (m,2H,-NCH2) CH2 CH2CH2SO3H).

[0118] The yields of raw materials and target products in Examples 1-6 are shown in Table 1.

[0119] Table 1. Yields of raw materials and target products in Examples 1-6

[0120]

[0121]

[0122] Test case

[0123] The target products prepared in Examples 1-6 were used in the tanning process of cattle hides, tanned according to the process in Table 2, and the shrinkage temperature of the raw leather was tested. The tensile strength, elongation at break, and tear strength of the raw leather were determined according to the methods in QB / T2710-2018 (Leather. Physical and mechanical tests. Determination of tensile strength and elongation) and QB / T2711-2005 (Leather. Physical and mechanical tests. Determination of tear strength: bilateral tear). The test results are shown in Table 3.

[0124] Table 2. Acid Immersion Tanning Process

[0125]

[0126] Table 3. Results of Shrinkage Temperature and Physical and Mechanical Properties Tests

[0127]

[0128]

[0129] Unless otherwise specified, the terms used in this invention have the meanings commonly understood by those skilled in the art.

[0130] The embodiments described in this invention are for illustrative purposes only and are not intended to limit the scope of protection of this invention. Those skilled in the art can make various other substitutions, changes and improvements within the scope of this invention. Therefore, this invention is not limited to the above embodiments, but is only defined by the claims.

Claims

1. A triazine derivative having a structure as shown in formula (1-1) or formula (1-2), In formula (1-1), R1 represents a halogen or a hydroxyl group; In formula (1-2), R1 represents an alkyl or hydroxyl group from C1 to C4, and R2 represents a halogen; In equations (1-1) and (1-2), m represents an integer from 2 to 6, and X represents Cl.

2. The triazine derivative according to claim 1, wherein, In formula (1-1), R1 represents Cl or a hydroxyl group; In formula (1-2), R1 represents methyl, ethyl, n-propyl, isopropyl or hydroxyl, and R2 represents Cl; In equations (1-1) and (1-2), m represents 3 or 4, and X represents Cl.

3. The triazine derivative according to claim 1 or 2, wherein, The triazine derivatives are selected from:

4. A method for preparing a triazine derivative according to any one of claims 1-3, comprising the following steps: S1: The aniline derivative with the structure shown in formula (2-1) is reacted with a sulfonate lactone with the structure shown in formula (2-2) to prepare an aniline sulfonic acid intermediate with the structure shown in formula (2-3); and S2: The aniline sulfonic acid intermediate is reacted with a trihalomycin with the structure shown in formula (2-4) to prepare the triazine derivative; Among them, the aniline derivatives with the structure shown in formula (2-1) have the following structures: R1, R2, m, and X are as defined in any one of claims 1-3.

5. The preparation method according to claim 4, wherein, In step S1, the aniline derivative and the sulfonyl lactone are reacted in an aprotic organic solvent at 30–120°C for 2–12 h to prepare the aniline sulfonic acid intermediate.

6. The preparation method according to claim 5, wherein, The aprotic organic solvent is selected from one or more of dichloromethane, 1,2-dichloroethane, petroleum ether, n-hexane, cyclohexane, and 1,4-dioxane.

7. The preparation method according to claim 5 or 6, wherein, The molar ratio of the aniline derivative to the sulfonyl lactone is 1:0.9 to 1.

8. The preparation method according to claim 4, wherein, In step S2, the aniline sulfonic acid intermediate and the trihalomycin are reacted at 10–30°C for 2–10 h in the presence of a surfactant and an acid-binding agent to prepare the triazine derivative.

9. The preparation method according to claim 8, wherein, The surfactant is selected from one or more of fatty alcohol polyoxyethylene ether, polyethylene glycol, and polypropylene glycol.

10. The preparation method according to claim 8, wherein, The acid-binding agent is selected from an aqueous solution of potassium hydroxide or sodium hydroxide with a concentration of 5-25 wt%.

11. The preparation method according to any one of claims 8-10, wherein, In step S2, the molar ratio of the trihalomyrizotin to the aniline sulfonic acid intermediate is 1:0.8-1; and / or The molar ratio of the trihalomyrizine to the surfactant is 1:0.005 to 0.015; and / or The acid-binding agent adjusts the pH of the reaction system to 5.0–7.

5.

12. Use of the triazine derivatives according to any one of claims 1-3 as leather tanning agents.

13. The use according to claim 12, wherein, The leather tanning agent is used in the leather tanning process where the raw hides are cowhide, buffalo hide, yak hide, or goat hide.

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