Synthesis method of bis-hydroxyethyl amino propyl hydroxyethyl oleylamine

Abstract

The invention provides a synthesis method of bis (hydroxyethyl) amino propyl hydroxyethyl oleylamine, which comprises the following steps: taking N-tert-butyloxycarbonyl-1, 3-propane diamine and ethylene oxide according to a set proportion, and reacting in a first organic solvent to obtain a first intermediate; reacting the first intermediate with a hydrochloric acid solution according to a set ratio to obtain a second intermediate; and taking the second intermediate, 1-bromo-cis-9-octadecene and alkali according to a set ratio to react in a second organic solvent to obtain a compound bis (hydroxyethyl) amino propyl hydroxyethyl oleylamine, and synthesizing the bis (hydroxyethyl) amino propyl hydroxyethyl oleylamine by adopting a green and environment-friendly method.

Description

Technical Field

[0001] The present invention relates to the field of fine chemicals, and in particular to a method for synthesizing bis(hydroxyethylaminopropyl)hydroxyethyloleylamine. Background Art

[0002] In the field of fine chemicals and chemical research, bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine is an organic compound with a unique structure. Its chemical structure includes amino, hydroxyethyl and long carbon chain alkyl groups. The combination of these structural units in the molecule gives the compound unique chemical properties.

[0003] From the perspective of structural characteristics, the amino group makes the molecule alkaline to a certain extent, enabling it to participate in a variety of acid-base reactions. It also provides the molecule with active sites for reacting with other acidic or electrophilic groups. The presence of hydroxyethyl groups increases the hydrophilicity of the molecule, which helps it to function in an aqueous environment, and its hydroxyl groups may also participate in reactions such as etherification and esterification. The long-chain alkyl group (such as the long chain of the oleylamine part) brings good lipophilicity, which makes bis(hydroxyethylaminopropyl)hydroxyethyloleylamine exhibit special interfacial activity in oil-water systems and has potential value in surface chemistry-related applications.

[0004] It is worth noting that there are certain similarities between bis(hydroxyethylaminopropylhydroxyethyl)oleylamine and olaflu. Olafur has important applications in related fields, especially in oral care products, where it exhibits excellent anti-caries properties. Its structural characteristics enable it to form an effective film on the surface of teeth, promoting the fusion of fluoride and tooth enamel. Similarly, the structure of bis(hydroxyethylaminopropylhydroxyethyl)oleylamine may give it similar film-forming or surface-active performance potential in some aspects. However, research on bis(hydroxyethylaminopropylhydroxyethyl)oleylamine in this regard has not yet been fully carried out.

[0005] At present, there is no report on the synthesis method of bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine. This situation seriously limits the further research and application development of this compound, and it is impossible to deeply explore its possible role in materials science, biomedicine and other fields, and it is difficult to determine whether it can provide new solutions or advantages in application scenarios similar to olaflu. Therefore, it is particularly urgent to develop an effective synthesis method of bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine. Summary of the invention

[0006] The object of the present invention is to provide a method for synthesizing bishydroxyethylaminopropyl hydroxyethyl oleylamine, which uses cheap and safe N-tert-butyloxycarbonyl-1,3-propylenediamine to react with ethylene oxide and 1-bromo-cis-9-octadecene in sequence to prepare bishydroxyethylaminopropyl hydroxyethyl oleylamine, and has the advantages of low cost and simple synthesis process.

[0007] To achieve the above purpose, the present technical scheme provides a method for synthesizing bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine, comprising the following steps: Taking a set ratio of N-tert-butyloxycarbonyl-1,3-propylenediamine and ethylene oxide to react in a first organic solvent to obtain a first intermediate; The first intermediate is reacted with a hydrochloric acid solution in a set ratio to obtain a second intermediate; The second intermediate, 1-bromo-cis-9-octadecene and a base in a set ratio are reacted in a second organic solvent to obtain a compound, bishydroxyethylaminopropylhydroxyethyl oleylamine.

[0008] The present invention provides a bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine, which is synthesized according to the above-mentioned synthesis method of bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine.

[0009] Compared with the prior art, this technical solution has the following characteristics and beneficial effects: This synthesis method has significant advantages in the selection of raw materials. All the raw materials used are common chemical raw materials with sufficient market supply and affordable prices, such as N-tert-butyloxycarbonyl-1,3-propylenediamine, etc., avoiding the use of scarce and expensive reagents. In terms of solvents, such as methanol and ethanol, they can not only effectively dissolve the reactants to promote the reaction, but also have the characteristics of easy recycling and treatment, reducing the adverse effects of solvent waste on the environment. The reaction conditions are mild, mostly carried out at room temperature or slightly higher temperatures, without the need for high temperature and high pressure, which greatly reduces energy consumption, while reducing side reactions caused by extreme conditions and improving the selectivity of the reaction. In addition, the reaction steps are reasonably designed, with high atom economy and good atom utilization, minimizing the generation of by-products, which is in line with the concept of green chemistry and effectively reduces the pressure on the environment.

[0010] The synthesized bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine has outstanding advantages. Its product chemical purity is as high as over 99%, thanks to the carefully designed reaction steps and effective purification measures, such as column chromatography separation or recrystallization. The high purity enables this compound to be used in many fields. As a standard chemical, it can provide accurate and reliable data support for quantitative and qualitative detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 The invention discloses a synthetic process route of bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine according to an embodiment of the invention.

[0012] Figure 2 This is the hydrogen nuclear magnetic resonance spectrum of the bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine obtained in Example 1 of the present invention.

[0013] Figure 3 This is a liquid chromatography purity spectrum of bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine obtained in Example 1 of the present invention.

[0014] Figure 4 This is the liquid chromatography-mass spectrometry spectrum of bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine obtained in Example 1 of the present invention. DETAILED DESCRIPTION

[0015] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0016] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0017] This scheme provides a method for synthesizing bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine, comprising the following steps: Taking a set ratio of N-tert-butyloxycarbonyl-1,3-propylenediamine and ethylene oxide to react in a first organic solvent to obtain a first intermediate; The first intermediate is reacted with a hydrochloric acid solution in a set ratio to obtain a second intermediate; The second intermediate, 1-bromo-cis-9-octadecene and a base in a set ratio are reacted in a second organic solvent to obtain a compound, bishydroxyethylaminopropylhydroxyethyl oleylamine.

[0018] The structural formula of the first intermediate is as follows: .

[0019] The amino group (-NH2) in N-tert-butyloxycarbonyl-1,3-propylenediamine in this scheme has strong nucleophilicity, and the electronegativity of the oxygen atom in the ethylene oxide molecule is greater than that of the carbon atom, so that the three-membered ring of ethylene oxide has a higher ring tension, and the carbon atom carries a partial positive charge, becoming an electrophilic center. The amino group attacks the carbon atom of ethylene oxide, and a nucleophilic addition reaction occurs, so that the three-membered ring of ethylene oxide opens, forming a new carbon-nitrogen bond, and generating a compound containing a hydroxyl group, i.e., the first intermediate.

[0020] The structural formula of the second intermediate is as follows: .

[0021] The tert-butyloxycarbonyl protecting group of the first intermediate of this scheme is removed under the action of hydrochloric acid solution. The hydrochloric acid provides an acidic environment to cause the tert-butyloxycarbonyl group to undergo a decomposition reaction to form a tert-butyl cation and carbon dioxide gas to escape, and the amino group is released at the same time to obtain a second intermediate.

[0022] The chemical structure of the synthesized bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine is shown in the following structure: .

[0023] The amino group in the second intermediate of this scheme again exerts its nucleophilicity, and the amino group attacks the carbon atom connected to the bromine atom in 1-bromo-cis-9-octadecene, undergoing a nucleophilic substitution reaction to form a new carbon-nitrogen bond, thereby introducing a long carbon chain alkyl group into the molecule, and finally obtaining bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine.

[0024] The process route diagram of the synthesis method of bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine is as follows: Figure 1 As shown in the figure, from the overall structure, there is a long carbon chain alkyl group in the molecule of bis(hydroxyethylaminopropyl)hydroxyethyloleylamine, and this part of the structure comes from oleylamine. The long carbon chain alkyl group gives the molecule good lipophilicity, which enables it to play an important role in non-polar environments or systems involving hydrophobic interactions. For example, in surfactant systems, the long carbon chain alkyl group helps the molecules to be oriented at the interface, thereby reducing the surface tension; the molecule also contains an amino group. The presence of the amino group makes the molecule alkaline and can react with the acid to form the corresponding salt. At the same time, the amino group is also an active reaction site and can participate in a variety of chemical reactions, such as alkylation reaction, acylation reaction, etc., which provides the possibility for further modification and functionalization of the molecule. In addition, the presence of the hydroxyethyl group increases the hydrophilicity of the molecule.

[0025] In some embodiments, the molar ratio of N-tert-butyloxycarbonyl-1,3-propylenediamine to ethylene oxide is 1:3 to 1:8. The advantage of this setting is that controlling the excess of ethylene oxide can ensure that the amino groups in N-tert-butyloxycarbonyl-1,3-propylenediamine are fully reacted, and the appropriate excess of ethylene oxide provides a high concentration of reactants in the early stage to accelerate the reaction. The concentration changes with the progress of the reaction to make the rate reasonable, which is conducive to a smooth reaction and reduces side reactions.

[0026] In some embodiments, the first organic solvent is selected as one or more of methanol, ethanol or isopropanol. In this solution, methanol, ethanol or isopropanol is selected as the first organic solvent. These first organic solvents have strong polarity and can dissolve reactants well, ensuring that the molecules are fully in contact to facilitate the reaction. Alcohols can stabilize reaction intermediates, reduce activation energy, promote nucleophilic addition reactions, and are relatively inert to ensure reaction selectivity. After the reaction is completed, due to their low boiling point, they can be easily removed by distillation or other methods, which is convenient for subsequent product separation and purification and reduces pollution.

[0027] Preferably, the first organic solvent is methanol.

[0028] In some embodiments, N-tert-butyloxycarbonyl-1,3-propylenediamine and ethylene oxide are reacted in a first organic solvent at room temperature, wherein the room temperature is 20° C. to 30° C., and the reaction time is 2 h to 3 h.

[0029] In some embodiments, ethylene oxide is dissolved in tetrahydrofuran to prepare an ethylene oxide-tetrahydrofuran solution, and N-tert-butyloxycarbonyl-1,3-propylenediamine and the ethylene oxide-tetrahydrofuran solution are reacted in a first organic solvent. This is because ethylene oxide is a highly active and somewhat dangerous compound with a low boiling point, flammable and explosive. Dissolving ethylene oxide in tetrahydrofuran to form a solution can reduce the volatility and activity of ethylene oxide, making it safer and more stable during storage and use, and can also more accurately control the amount of ethylene oxide added to the reaction system.

[0030] In some embodiments, the molar concentration of the ethylene oxide-tetrahydrofuran solution is 2.0-4.0 M.

[0031] In some embodiments, the first intermediate is subjected to a Boc deprotection reaction with a hydrochloric acid solution to obtain a second intermediate. Such a Boc deprotection can release the amino group in the first intermediate to provide an active site for subsequent reactions.

[0032] In some embodiments, the molar ratio of the first intermediate to the hydrochloric acid solution is 1:1 to 1:5. In some embodiments, the hydrochloric acid solution is a hydrochloric acid organic solvent obtained by dissolving hydrochloric acid in an organic solvent, and the first intermediate reacts with the hydrochloric acid organic solvent, wherein the organic solvent for dissolving the hydrochloric acid is selected from one or more of 1,4-dioxane, ethanol or methanol, and the hydrochloric acid organic solvent provides a homogeneous environment for the first intermediate to facilitate the de-Boc reaction.

[0033] Preferably, the organic solvent for dissolving the hydrochloric acid is a 1,4-dioxane solution.

[0034] In some embodiments, the molar concentration of the hydrochloric acid organic solvent is 2.0-4.0 M.

[0035] In some embodiments, the reaction temperature of the first intermediate and the hydrochloric acid solution is 20°C-30°C, and the reaction time is 2h-5h. The setting of the reaction conditions can accurately remove the Boc protecting group and ensure the selectivity of the reaction, avoid the influence of other functional groups, reduce side reactions, and do not require additional temperature control equipment. It is energy-saving and easy to operate, and the stable environment is conducive to repeated experiments.

[0036] In some embodiments, the molar ratio of the second intermediate, 1-bromo-cis-9-octadecene and the base is 1:1:2 to 1:1.5:4. An appropriate excess of 1-bromo-cis-9-octadecene (molar ratio 1:1 to 1:1.5) can ensure that the amino group has sufficient reaction partners, reduce the residual unreacted amino group, and improve the conversion rate of the second intermediate, which is beneficial to increase the yield of the target product bis-hydroxyethylaminopropyl hydroxyethyl oleylamine, and a sufficient amount of base can neutralize the generated acid in time to avoid acid accumulation and inhibition of the reaction.

[0037] In some embodiments, the second organic solvent is selected as one or more combinations of anhydrous acetonitrile or anhydrous methanol or anhydrous tetrahydrofuran. The second organic solvents selected in this scheme are all polar solvents, which can dissolve the reactants well to promote full contact of molecules and facilitate nucleophilic substitution reactions. Secondly, it has good chemical stability at the reaction temperature, will not cause side reactions, and can adjust the physical and chemical properties of the reaction system, such as stabilizing intermediates, affecting activation energy, and promoting the reaction. Furthermore, the low boiling point is convenient for removal by distillation after the reaction, reducing solvent residues, facilitating product separation and purification, and reducing costs.

[0038] Preferably, the second organic solvent is anhydrous acetonitrile.

[0039] In some embodiments, the base is selected from sodium hydroxide or cesium carbonate or diazabicyclo. Preferably, the base is selected from diazabicyclo.

[0040] In some embodiments, the reaction temperature for reacting the second intermediate with 1-bromo-cis-9-octadecene and a base in a second organic solvent is 80° C.-85° C., and the reaction time is 12 h-16 h.

[0041] In some embodiments, the present scheme further comprises the step of purifying the bis(hydroxyethylaminopropylhydroxyethyl)oleylamine by column chromatography separation or recrystallization.

[0042] The synthesis method of the bishydroxyethylaminopropyl hydroxyethyl oleylamine provided in the scheme has simple synthesis steps, and the synthesized bishydroxyethylaminopropyl hydroxyethyl oleylamine is easy to separate and purify, and the chemical purity of the obtained product reaches more than 99%.

[0043] The above preparation method is further described below by means of specific examples: All raw materials used in the examples of the present invention are commercially available or can be prepared in-house according to known techniques, and their purity is all industrial grade.

[0044] Related reagents: All raw materials used in the examples are commercially available and their purity is industrial grade.

[0045] DBU, 1-bromo-cis-9-octadecene (Shanghai Bidex Pharmaceutical Technology Co., Ltd.); N-tert-butyloxycarbonyl-1,3-propanediamine, ethylene oxide (Shanghai MacLean Biochemical Technology Co., Ltd.); sodium hydroxide, anhydrous acetonitrile, anhydrous methanol, anhydrous tetrahydrofuran, dichloromethane, methanol (analytical grade, Shanghai Anpu Laboratory Technology Co., Ltd.). Unless otherwise specified, all reagents were used directly.

[0046] Example 1 Synthesis of bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine: The specific synthesis steps are as follows: S1: In a 50 mL round-bottom flask, N-tert-butyloxycarbonyl-1,3-propanediamine (500 mg, 2.86 mmol) was dissolved in 20 mL methanol, and then ethylene oxide (3.0 mL; 5.0 mol / L in THF) was added. The reaction was allowed to react at room temperature for 3 h. During the reaction, the reaction progress was monitored by TLC (V 二氯甲烷 :V 氨的甲醇 =10:1, potassium permanganate color development), the reaction formula is as follows:

[0047] After the reaction, the organic phase was concentrated, mixed with silica gel powder and the organic solvent was dried, and purified by column chromatography (V 二氯甲烷 :V 甲醇 =50:1~30:1~20:1), the solvent was spin-dried to obtain a light yellow transparent oil (829 mg, 2.71 mmol), the yield based on N-tert-butyloxycarbonyl-1,3-propylenediamine: 94.75%.

[0048] S2: At room temperature, intermediate A (829 mg, 2.71 mmol) was dissolved in a 1,4-dioxane solution of hydrochloric acid (5 mL; 2 M) in a 25 mL round-bottom flask and stirred at room temperature for 3 hours. The reaction progress was monitored by TLC (V 二氯甲烷 :V 氨的甲醇 =1:1). The reaction formula is as follows:

[0049] After the reaction, the solvent was dried, the organic phase was concentrated, and the crude product was obtained by column chromatography (V 二氯甲烷 :V甲醇 =30:1-15:1) was purified to give a light yellow oil (546 mg, 2.65 mmol). The yield calculated based on intermediate A was 97.78%.

[0050] S3: In a 100 mL three-necked round-bottom flask, intermediate B (546 mg, 2.65 mmol), DBU (806 mg, 2.00 eq) and 1-bromo-cis-9-octadecene (965.94 mg, 1.10 eq) were added in sequence, dissolved in anhydrous acetonitrile (30 mL) under nitrogen protection and refluxed for 16 hours. The reaction progress was monitored by TLC (V 二氯甲烷 :V 氨的甲醇 =8:1, potassium permanganate color development). The reaction formula is as follows:

[0051] After the reaction was completed, the reaction flask was cooled to room temperature, filtered and washed with dichloromethane to remove the precipitate, the organic phase was concentrated, and vacuum dried to obtain a crude product. 二氯甲烷 :V 甲醇 =30:1~20:1~10:1) was purified to give a transparent oil (1.11 g, 2.43 mmol). The yield calculated based on intermediate B was 91.69%.

[0052] The product obtained in this example uses CDCl3 as solvent and is detected by a Brune-400M nuclear magnetic resonance instrument. Figure 2 At the same time, the product samples obtained in this example were subjected to liquid chromatography-mass spectrometry (LC-MS) detection, as shown in FIG. Figure 4 As shown, the mass spectrometry data showed LC-MS m / z 457.4 [M + ], which is consistent with the molecular weight of bis(hydroxyethylaminopropyl)hydroxyethyloleylamine (olafluor analog, 9-enyl) compound (M=456.4).

[0053] The product samples obtained in this example were measured by liquid chromatography using dichloromethane as solvent under the following conditions: Method No.: 30 % AD Column: Athena C 18 250mm*4.6mm, 5 um Column temperature: 30°C Mobile phase: A: acetonitrile; D: 0.02 mol / L ammonium acetate Gradient: 0 min 30% A; 2 min 30% A; 4 min 75% A; 15 min 75% A; 15.5 min 30% A; 18.5 min 30% A Flow rate: 0.6 mL / min Detector: CAD Sample: 10 uL, 0.3 mg / mL in dichloromethane + methanol.

[0054] The purity spectrum measured is as follows Figure 3 As shown, it can be seen that the sample purity reaches 100% and can be used as a high-purity RM-level standard.

[0055] Embodiment 2 Synthesis of bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine: S1: In a 50 mL round-bottom flask, N-tert-butyloxycarbonyl-1,3-propanediamine (500 mg, 2.86 mmol) was dissolved in 15 mL of ethanol, and then ethylene oxide (3.0 mL; 3.0 mol / L in THF) was added. The reaction was allowed to react at room temperature for 2.5 hours. During the reaction, the reaction progress was monitored by TLC (V 二氯甲烷 :V 氨的甲醇 =10:1, potassium permanganate color development). The reaction formula is as follows:

[0056] After the reaction, the organic phase was concentrated, mixed with silica gel powder and the organic solvent was dried, and purified by column chromatography (V 二氯甲烷 :V 甲醇 =50:1~30:1~20:1), the solvent was spin-dried to obtain a light yellow transparent oil (798 mg, 2.61 mmol), the yield based on N-tert-butyloxycarbonyl-1,3-propylenediamine: 91.25%.

[0057] S2: At room temperature, intermediate A (798 mg, 2.61 mmol) was dissolved in a methanol solution of hydrochloric acid (3 mL; 1.5 M) in a 25 mL round-bottom flask and stirred at room temperature for 3 hours. The reaction progress was monitored by TLC (V 二氯甲烷 :V 氨的甲醇 =1:1). The reaction formula is as follows:

[0058] After the reaction, the solvent was dried, the organic phase was concentrated, and the crude product was obtained by column chromatography (V 二氯甲烷 :V 甲醇 =30:1-15:1) was purified to give a light yellow oil (513 mg, 2.49 mmol) with a yield of 95.55% based on intermediate A.

[0059] S3: In a 100 mL three-necked round-bottom flask, intermediate B (513 mg, 2.49 mmol), sodium hydroxide (299 mg, 3.00 eq) and 1-bromo-cis-9-octadecene (990.13 mg, 1.20 eq) were added in sequence, dissolved in anhydrous methanol (30 mL) under nitrogen protection, and refluxed for 16 hours. The reaction progress was monitored by TLC (V 二氯甲烷 :V 氨的甲醇 =8:1, potassium permanganate color development). The reaction formula is as follows:

[0060] After the reaction was completed, the reaction flask was cooled to room temperature, filtered and washed with dichloromethane to remove the precipitate, the organic phase was concentrated, and vacuum dried to obtain a crude product. 二氯甲烷 :V 甲醇 =30:1~20:1~10:1) was purified to give a transparent oil (1.01 g, 2.21 mmol) with a yield of 88.75% based on intermediate B.

[0061] The present invention is not limited to the above-mentioned optimal implementation mode. Anyone can derive other various forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, all technical solutions that are the same or similar to those of the present application fall within the protection scope of the present invention.

Claims

1. A method for synthesizing bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine, characterized in that: The following steps are involved: Taking a set ratio of N-tert-butyloxycarbonyl-1,3-propylenediamine and ethylene oxide to react in a first organic solvent to obtain a first intermediate; The first intermediate is reacted with a hydrochloric acid solution in a set ratio to obtain a second intermediate; The second intermediate, 1-bromo-cis-9-octadecene and a base in a set ratio are reacted in a second organic solvent to obtain a compound, bishydroxyethylaminopropylhydroxyethyl oleylamine.

2. The method for synthesizing bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine according to claim 1, characterized in that: The structural formula of the first intermediate is shown below: ； The structural formula of the second intermediate is shown below: ； The chemical structure of bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine is as follows: 。 3. The method for synthesizing bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine according to claim 1, characterized in that: The molar ratio of N-tert-butyloxycarbonyl-1,3-propylenediamine to ethylene oxide is 1:3 to 1:

8.

4. The method for synthesizing bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine according to claim 1, characterized in that: The first organic solvent is selected from one or more of methanol, ethanol or isopropanol.

5. The method for synthesizing bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine according to claim 1, characterized in that: Ethylene oxide is dissolved in tetrahydrofuran to prepare an ethylene oxide-tetrahydrofuran solution, wherein the molar concentration of the ethylene oxide-tetrahydrofuran solution is 2.0-4.0 M.

6. The method for synthesizing bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine according to claim 1, characterized in that: The hydrochloric acid solution is a hydrochloric acid organic solvent obtained by dissolving hydrochloric acid in an organic solvent. The first intermediate reacts with the hydrochloric acid organic solvent, wherein the organic solvent for dissolving the hydrochloric acid is selected from one or more of 1,4-dioxane, ethanol or methanol.

7. The method for synthesizing bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine according to claim 1, characterized in that: The reaction temperature of the first intermediate and the hydrochloric acid solution is 20°C-30°C, and the reaction time is 2h-5h.

8. The method for synthesizing bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine according to claim 1, characterized in that: The molar ratio of the second intermediate, 1-bromo-cis-9-octadecene and the base is 1:1:2 to 1:1.5:

4.

9. The method for synthesizing bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine according to claim 1, characterized in that: The reaction temperature of the second intermediate, 1-bromo-cis-9-octadecene and base in the second organic solvent is 80° C.-85° C., and the reaction time is 12 h-16 h.

10. A bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine, characterized in that: The bis(hydroxyethylaminopropyl)hydroxyethyl oleylamine is synthesized according to the synthesis method of any one of claims 1 to 9.

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