A benzothiazole amino acid ester derivative, a preparation method and use thereof

Abstract

The present application provides a kind of benzothiazole amino acid ester derivative and its preparation method and purposes, the structural formula of the benzothiazole amino acid ester derivative is as shown in formula I, formula II or formula III. Wherein, R1 It is selected from H atom or the linear or branched alkyl of carbon atom number 8~20, R2 It is selected from H,‑CH(CH3)2,‑(CH2) n COOR1 Wherein n=1‑6, benzothiazole amino acid ester derivative of the present application has significantly antiwear, friction reducing and anti-rust performance, while also having excellent thermal stability.

Description

Technical Field

[0001] This invention belongs to the field of lubricating oil additive technology, and in particular relates to a benzothiazole amino acid ester derivative, its preparation method and uses. Background Technology

[0002] Lubricating oil, as a key functional material, plays a vital role in the smooth operation and extended service life of mechanical equipment. Its performance stability directly affects the safe and efficient operation of mechanical systems. Additives in lubricating oils play an irreplaceable role in performance optimization, improving key properties such as friction reduction, wear resistance, rust prevention, and corrosion prevention. Traditional lubricating oils typically rely on the synergistic use of multiple functional additives, such as dispersants, anti-wear / extreme pressure agents, antioxidants, rust inhibitors, and friction modifiers. However, the interactions between different additives are often complex, frequently leading to poor compatibility or significant antagonistic effects, thus affecting the stability and predictability of the overall lubricating oil performance. Furthermore, achieving performance optimization usually requires extensive experimental verification of various components and their proportions, resulting in prolonged R&D cycles and high testing costs, hindering efficient and sustainable product development. To address these challenges, the development of multifunctional lubricating oil additives has become an important research direction.

[0003] With the rapid development of industry, the requirements for mechanical equipment are becoming increasingly stringent, necessitating operation under conditions such as high temperature, high speed, and heavy load. These conditions significantly exacerbate friction and wear. Studies show that nearly 80% of mechanical failures are caused by excessive wear and lubrication-related problems. Therefore, lubricating oils must possess reliable friction-reducing and anti-wear properties. However, during long-term operation, equipment may be exposed to high humidity or even high-salt environments, which can easily lead to corrosion of components and subsequently equipment failure. Therefore, developing multifunctional additives that combine friction reduction, anti-wear, and rust prevention properties is of great significance for improving the reliability and durability of mechanical systems. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a benzothiazole amino acid ester derivative, its preparation method and uses, for improving the friction reduction, anti-wear and rust prevention properties of lubricating greases, while simplifying the lubricating grease formulation.

[0005] To achieve the above and other related objectives, the present invention provides a benzothiazole amino acid ester derivative, its preparation method, and its uses.

[0006] The first aspect of this invention provides a benzothiazole amino acid ester derivative, the structural formula of which is shown in Formula I, Formula II or Formula III:

[0007] , , .

[0008] R1 is selected from H atoms or straight-chain or branched alkyl groups with 8 to 20 carbon atoms, such as C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C19, or C20 straight-chain or branched alkyl groups. Within this range, the number of carbon atoms has little effect on the physical properties of the final product; generally, straight-chain or branched alkyl groups with C8 to C16 are preferred.

[0009] R2 is selected from H, -CH(CH3)2, and -(CH2). n COOR1 , , , where n = 1-6, such as n can be 1, 2, 3, 4, 5 or 6.

[0010] The applicant of this application discovered that when the number of carbon atoms in R1 is less than 4 or greater than 20, the oil solubility of the product decreases, while when the number of carbon atoms in R1 is 8 to 20, it can ensure good solubility and dispersibility in base oil.

[0011] Preferably, the benzothiazole amino acid ester derivative comprises one or more of the following: compound I-1, compound I-2, compound I-3, compound II-1, or compound III-1; the structural formula is shown below:

[0012] , , , , .

[0013] More preferably, the benzothiazole amino acid ester derivative comprises compounds as shown in Table 1:

[0014] Table 1. Benzothiazol amino acid ester derivatives

[0015]

[0016] In this application, when R1 is H, the benzothiazole amino acid ester derivative forms a carboxylic acid functional group; when R1 is an 8-20 straight-chain or branched alkyl group, an ester bond is formed at the corresponding position. The different functional groups resulting from this substituent lead to slight differences in application performance, but these differences are mainly manifested in dispersibility. Rust prevention and anti-wear properties do not show significant differences in all scenarios. For example, although the benzothiazole amino acid ester derivative formed when R1 is H has poor dispersibility in lubricating oil (compared to R1 without H), it can still be used as a rust inhibitor in water-based lubricating oils or greases, and also as a rust inhibitor in semi-solid greases. However, in some greases with high viscosity or consistency, its difficulty in dispersion affects its final rust prevention or anti-wear performance. But if effective dispersion can be achieved through other dispersion methods (especially physical methods), it still has good anti-wear and rust prevention properties. For example, benzothiazole amino acid ester derivatives formed when R1 is a straight-chain or branched alkyl group of 8 to 20 can be more effectively dispersed in various general lubricating oils and greases, and also exhibit good rust prevention and anti-wear properties.

[0017] The second aspect of the present invention provides a method for preparing compounds of the structural formulas shown in Formula I and Formula II of benzothiazole amino acid ester derivatives, comprising: using 2-chlorobenzothiazole and amino acids as reactants and using a base as a catalyst, a substitution reaction is carried out to obtain carboxybenzothiazole amine; further, using carboxybenzothiazole amine as a reactant and reacting with an alkyl alcohol, an esterification reaction is carried out under the action of a catalyst to obtain the benzothiazole amino acid ester derivatives of Formula I and Formula II.

[0018] Preferably, the amino acid is one or more selected from glutamic acid, glycine, aspartic acid, serine, tryptophan, histidine, valine, tyrosine, or proline.

[0019] Preferably, the alkyl alcohol is a straight-chain or branched alkyl alcohol with 8 to 20 carbon atoms, such as 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms.

[0020] Preferably, the molar ratio of 2-chlorobenzothiazole to amino acids is 1:(1~1.6), such as 1:1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, or 1:1.6. More preferably, the molar ratio is 1:1. A molar ratio that is too large will result in excess 2-chlorobenzothiazole, which will increase the difficulty of post-processing and lead to lower product purity. A molar ratio that is too small will result in excess amino acids, reduced reaction efficiency, and increased costs.

[0021] Preferably, the alkaline catalyst is one or more selected from triethylamine, potassium carbonate, sodium carbonate, pyridine, or sodium hydroxide. More preferably, the alkaline catalyst is sodium hydroxide.

[0022] Preferably, the molar ratio of 2-chlorobenzothiazole to the base catalyst is 1:(2~4), such as 1:2, 1:2.5, 1:3, 1:3.5 or 1:4. If the molar ratio is too large, the reaction will be difficult to proceed in the forward direction, resulting in a low yield; if the molar ratio is too small, the base catalyst will be in excess, the reaction cost will be too high, and the economic benefits will be affected.

[0023] Preferably, the molar ratio of alkyl alcohol to carboxybenzothiazolamine is (1~2):1, such as 1:1, 1.5:1 or 2:1. If the molar ratio is too large, the excess alkyl alcohol will be difficult to remove, affecting the purity of the target product; if the molar ratio is too small, the reaction will be incomplete, affecting the esterification yield.

[0024] Preferably, the reaction temperature for the substitution reaction is 50-150℃, such as 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, 110℃, 120℃, 130℃, 140℃, or 150℃. A reaction temperature above 150℃ will lead to an increase in side reactions; a reaction temperature below 50℃ will make the reaction difficult to proceed.

[0025] Preferably, the reaction system of the substitution reaction further includes a reaction solvent, which is selected from one or both of dimethyl sulfoxide (DMSO) or N,N-dimethylformamide (DMF).

[0026] Preferably, the catalyst for the esterification reaction is one or more of p-toluenesulfonic acid, a solid superacid, or a cation exchange resin. More preferably, the catalyst is p-toluenesulfonic acid.

[0027] Preferably, the molar ratio of the catalyst to the alkyl alcohol in the esterification reaction is (1~2):1, such as 1:1, 1.5:1, or 2:1. More preferably, the molar ratio is 1:1. If the molar ratio is too large, there will be an excess of catalyst, which will increase the cost; if the molar ratio is too small, the reaction will be difficult to proceed in the forward direction.

[0028] Preferably, the reaction system for the esterification reaction further includes a reaction solvent, which is one or more of toluene, cyclohexane, or petroleum ether. More preferably, the reaction solvent is toluene.

[0029] Preferably, the reaction time for the heating substitution reaction is 10-16 hours, such as 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, or 16 hours. Preferably, the reaction time is 12 hours.

[0030] Preferably, the heating substitution reaction further includes a post-treatment step, which is washing. Preferably, the washing is performed using deionized water and then filtering. The volume of water added is at least twice the volume of the reaction liquid, such as 2, 3, 4, 5, or 6 times.

[0031] Preferably, the esterification reaction time is 10-16 hours, such as 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, or 16 hours. Preferably, the reaction time is 12 hours.

[0032] Preferably, the esterification reaction further includes a post-processing step, which includes extraction, washing, concentration, and purification. More preferably, the extraction involves adding deionized water, adjusting the pH to 6, adding ethyl acetate, stirring, and separating the organic phase into layers; the washing involves washing the organic phase with water at least three times to separate the organic phase; the concentration involves distilling the organic phase under reduced pressure; and the purification involves eluting by column chromatography, followed by distilling the organic phase under reduced pressure and drying it under vacuum. Those skilled in the art can set specific amounts of relevant reagents based on the actual operations of extraction, washing, and column chromatography, as long as the reaction product system achieves the purpose of separation and purification. For example, specifically, the volume of ethyl acetate added during extraction is at least one times the volume of the reaction system, such as one, two, three, or four times; the volume of water added during washing is at least one times the volume of ethyl acetate, such as one, two, three, or four times.

[0033] Preferably, the benzothiazole amino acid ester derivative compounds with the structural formulas shown in Formula I and Formula II are prepared using the above preparation method. The specific synthetic route is as follows:

[0034] Step 1: 2-Chlorobenzothiazole reacts with amino acids via a substitution reaction to yield carboxybenzothiazole amine. The reaction route is as follows:

[0035] 1) When preparing the intermediate of compound I-1, the amino acid is glycine, and the reaction route is as follows:

[0036] ;

[0037] 2) When preparing the intermediate of compound I-2, the amino acid can be selected from those with the general formula COOH(CH2). n The reaction route for CH(NH2)COOH, where n = 1-6 (e.g., n can be 1, 2, 3, 4, 5, or 6) of amino acids, is as follows:

[0038] ;

[0039] More preferably, when the amino acid is aspartic acid, compound I-2-1 is obtained; when the amino acid is glutamic acid, compound I-2-2 is obtained.

[0040] 3) When preparing the intermediate of compound I-3, the amino acid is tryptophan, and the reaction route is as follows:

[0041] .

[0042] 4) When preparing the intermediate of compound II-1, the amino acid is proline, and the reaction route is as follows:

[0043] .

[0044] Step 2: Carboxybenzothiazole amine is esterified with alkyl alcohol R1OH to obtain benzothiazole amino acid ester derivatives. The specific synthetic route is as follows:

[0045] 1) When preparing compound I-1, the reaction route is as follows:

[0046] ;

[0047] 2) When preparing compound I-2, the reaction route is as follows:

[0048] ;

[0049] Where n = 1-6, such as n can be 1, 2, 3, 4, 5 or 6;

[0050] 3) When preparing compound I-3, the reaction route is as follows:

[0051] ;

[0052] 4) When preparing compound II-1, the reaction route is as follows:

[0053] ;

[0054] Wherein, R1 is selected from H atoms or straight-chain or branched alkyl groups having 8 to 20 carbon atoms, wherein the number of carbon atoms can be 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20.

[0055] The third aspect of the present invention provides a method for preparing a benzothiazole amino acid ester derivative as shown in Formula III, comprising: a first step reaction: using α-haloacyl halide and alkyl alcohol as reactants, a substitution reaction is carried out under the action of a catalyst to obtain an intermediate; a second step reaction: the obtained intermediate is further reacted with 2-aminobenzothiazole to prepare the benzothiazole amino acid ester derivative of Formula III.

[0056] Preferably, the α-haloacyl halide is one or more of fluoroacetyl chloride, bromoacetyl bromide, or chloroacetyl chloride. More preferably, the α-haloacyl halide is bromoacetyl bromide.

[0057] Preferably, the alkyl alcohol is a branched or straight-chain alkyl alcohol with 8 to 20 carbon atoms, wherein the number of carbon atoms can be 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20.

[0058] Preferably, the molar ratio of α-haloacyl halide to alkyl alcohol is 1:(0.7~1), such as 1:0.7, 1:0.8, 1:0.9 or 1:1. More preferably, the molar ratio is 1:1. If the molar ratio is too large, the α-haloacyl halide will be in excess, making post-processing complicated and increasing costs; if the molar ratio is too small, the alkyl alcohol will be in excess, resulting in incomplete reaction and affecting product purity.

[0059] Preferably, the reaction temperature of the first step is -5 to 5°C, such as -5 to 0°C or 0 to 5°C. More preferably, the reaction temperature is 0 to 5°C. If the reaction temperature is too high (e.g., 25°C), the reaction will be violent; if the reactant temperature is too low (e.g., -20°C), the reaction will be incomplete.

[0060] Preferably, the molar ratio of the catalyst to the alkyl alcohol in the first step reaction is 1:(1.0:1.5), such as 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4, or 1:1.5. If the molar ratio is too large, too much catalyst is used, increasing costs; if the molar ratio is too small, insufficient catalyst is used, leading to incomplete reaction and excess raw materials.

[0061] Preferably, the reaction time for the first step is 10-16 hours, such as 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, or 16 hours. Preferably, the reaction time is 12 hours.

[0062] Preferably, after the first step reaction is completed, a post-processing step is included, wherein the post-processing step is column chromatography separation.

[0063] Preferably, the molar ratio of the intermediate to 2-aminobenzothiazole is (2~3):1, such as 2:1, 2.5:1, or 3:1. More preferably, the molar ratio is 2:1. If the molar ratio is too large, the intermediate will remain, increasing the difficulty of post-processing and affecting the purity of the product; if the molar ratio is too small, 2-aminobenzothiazole will remain, leading to incomplete reaction, excess raw materials, and increased costs.

[0064] Preferably, the preparation method further includes a reaction solvent, wherein the reaction solvent is one or more of dichloromethane, tetrahydrofuran, or N,N-dimethylformamide;

[0065] Preferably, the reaction time for the second step is 10-16 hours, such as 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, or 16 hours. Preferably, the reaction time is 12 hours.

[0066] Preferably, the second reaction step further includes a post-processing step, which includes extraction, washing, concentration, and purification. More preferably, the extraction involves adding deionized water, adjusting the pH to 5, adding ethyl acetate, stirring, and separating the organic phase into layers; the washing involves washing the organic phase with water at least three times to separate the organic phase; the concentration involves distilling the organic phase under reduced pressure; and the purification involves eluting by column chromatography, followed by distilling the organic phase under reduced pressure and drying it under vacuum. Those skilled in the art can set specific amounts of relevant reagents based on the actual operations of extraction, washing, and column chromatography, as long as the reaction product system achieves the purpose of separation and purification. For example, specifically, the volume of ethyl acetate added during extraction is at least one times the volume of the reaction system, such as 1, 2, 3, or 4 times; the volume of water added during washing is at least one times the volume of ethyl acetate, such as 1, 2, 3, or 4 times.

[0067] Preferably, when preparing the benzothiazole amino acid ester derivative compound with the structural formula of Formula III-1 using the above preparation method, the specific synthetic route is as follows:

[0068] Step 1: α-Haloacyl halides react with alkyl alcohols via a substitution reaction to obtain the intermediate of compound III-1. The specific synthetic route is as follows:

[0069] ;

[0070] Wherein, X is selected from Br, F, I or Cl; R1 is independently selected from H atoms or straight-chain or branched alkyl groups having 8 to 20 carbon atoms, wherein the number of carbon atoms can be 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20.

[0071] Step 2: The intermediate of compound III-1 is reacted with 2-aminobenzothiazole to prepare the benzothiazole amino acid ester derivative of formula III-1. The specific synthetic route is as follows:

[0072] ;

[0073] Wherein, X is selected from Br, F, I or Cl; R1 is selected from H atoms or straight-chain or branched alkyl groups with 8 to 20 carbon atoms, wherein the number of carbon atoms can be 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20.

[0074] More preferably, when the alkyl alcohol is n-dodecyl alcohol, a compound of formula III-1-1 is obtained.

[0075] The fourth aspect of the present invention provides the use of any of the benzothiazole amino acid ester derivatives described above as additives for lubricating oils or greases.

[0076] Preferably, the application includes at least one of the following 1) to 3):

[0077] 1) Reduce the diameter of the wear scar;

[0078] 2) Reduce friction;

[0079] 3) Prevent or slow down rusting.

[0080] Preferably, the benzothiazole amino acid ester derivative is used as an additive for lubricating oils or greases to reduce the wear scar diameter of the lubricating oil and / or grease.

[0081] Preferably, the benzothiazole amino acid ester derivative is used as an additive for lubricating oils or greases to reduce the coefficient of friction of the lubricating oil and / or grease, thereby reducing friction.

[0082] Preferably, the benzothiazole amino acid ester derivative is used as a lubricating oil or grease additive to prevent or slow down rusting.

[0083] The fifth aspect of the present invention provides a lubricating oil or grease containing any of the benzothiazole amino acid ester derivatives described above.

[0084] Preferably, the amount of benzothiazole amino acid ester derivative added to the lubricating oil or grease is 0.1-5.0 wt%, based on the weight of the base oil or grease, such as 0.1 wt%, 0.5 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, or 5 wt%. More preferably, the amount added is 0.5-2.0 wt%.

[0085] More preferably, the amount of the benzothiazole amino acid ester derivative added is 0.5-2.0 wt%, more preferably 1.0-2.0 wt%, based on the weight of the base oil and / or base grease.

[0086] Preferably, the base oil is a low-viscosity base oil. The low-viscosity base oil has a kinematic viscosity of 2~10 mm at 100°C. 2 ·s -1 For example, it can be 2mm 2 ·s -1 3mm 2 ·s -1 4mm 2 ·s -1 5mm 2 ·s -1 6mm 2 ·s -1 7mm 2 ·s -1 8mm2 ·s -1 9mm 2 ·s -1 or 10mm 2 ·s -1 .

[0087] More preferably, the low-viscosity base oil is a low-viscosity III+ hydrocarbon base oil, polyalphaolefin, or synthetic ester.

[0088] As described above, the beneficial effects of the present invention are as follows:

[0089] 1. The benzothiazole amino acid ester derivative provided by this invention contains sulfur-nitrogen heterocycles, which can improve the adsorption of the compound as a lubricating additive on the metal surface, thereby improving its friction-reducing and anti-wear properties; in addition, the introduction of an amino acid ester structure with anti-rust effect into its structure can improve the anti-rust ability of the oil; the long-chain alkyl in the structure can ensure its solubility in base oil.

[0090] 2. The benzothiazole amino acid ester derivative of the present invention introduces functional groups such as amino acid esters into the structure based on the benzothiazole ring. Compared with the prior art, the benzothiazole amino acid ester derivative of the present application has significant advantages in anti-wear, friction reduction and anti-corrosion properties.

[0091] 3. The benzothiazole amino acid ester derivatives of the present invention have excellent thermal stability, with initial decomposition temperatures all greater than 300°C. Attached Figure Description

[0092] Figure 1 The image shows the hydrogen nuclear magnetic resonance spectrum of the intermediate compound prepared in Example 1 of this invention.

[0093] Figure 2 The photon nuclear magnetic resonance (NMR) spectrum of benzothiazole amino acid ester derivative I-1-1 prepared in Example 1 of this invention is shown.

[0094] Figure 3 The infrared spectrum of benzothiazole amino acid ester derivative I-1-1 prepared in Example 1 of this invention.

[0095] Figure 4 The image shows a comparison of the wear scar morphology of the blank sample of III+ base oil CTL4 and the sample of III+ base oil CTL4 with added benzothiazole amino acid ester derivative I-1-1 (2.0 wt%) prepared in Example 1 on a four-ball friction tester.

[0096] Figure 5This is a comparison of the friction curves of the blank sample of III+ base oil CTL4 and the sample of III+ base oil CTL4 with added benzothiazole amino acid ester derivative I-1-1 (1.0 wt%) prepared in Example 1 on the UMT test machine.

[0097] Figure 6 The impedance comparison diagram on the electrochemical workstation is shown for the blank sample of III+ base oil CTL4 and the sample of III+ base oil CTL4 with added benzothiazole amino acid ester derivative I-1-1 (1.0 wt%) prepared in Example 1 of the present invention.

[0098] Figure 7 The image shows the hydrogen nuclear magnetic resonance spectrum of the intermediate compound prepared in Example 5 of this invention.

[0099] Figure 8 The infrared spectrum of the intermediate compound prepared in Example 5 of this invention.

[0100] Figure 9 The photon nuclear magnetic resonance (NMR) spectrum of benzothiazole amino acid ester derivative III-1-1 prepared in Example 5 of this invention is shown.

[0101] Figure 10 The infrared spectrum of benzothiazole amino acid ester derivative III-1-1 prepared in Example 5 of this invention.

[0102] Figure 11 This is a comparison of the wear scar morphology on a four-ball friction tester between the blank sample of III+ base oil CTL4 and the sample of III+ base oil CTL4 with added benzothiazole amino acid ester derivative III-1-1 (2.0 wt%) prepared in Example 5 of the present invention.

[0103] Figure 12 This is a comparison of the friction curves of the blank sample of III+ base oil CTL4 and the sample of III+ base oil CTL4 with added benzothiazole amino acid ester derivative III-1-1 (1.0 wt%) prepared in Example 5 of the present invention on the UMT test machine.

[0104] Figure 13 The impedance comparison diagram on the electrochemical workstation is shown for the blank sample of III+ base oil CTL4 and the sample of III+ base oil CTL4 with added benzothiazole amino acid ester derivative III-1-1 (1.0 wt%) prepared in Example 5 of the present invention.

[0105] Figure 14This is a comparison of the corrosion of steel rods on a liquid phase corrosion testing machine between the blank sample of III+ base oil CTL4 and the sample of III+ base oil CTL4 with added benzothiazole amino acid ester derivative III-1-1 (0.5wt%) prepared in Example 5 of the present invention.

[0106] Figure 15 This is a comparison chart showing the corrosion of a blank sample of III+ base oil CTL4 and a sample of III+ base oil CTL4 with added benzothiazole amino acid ester derivative I-1-1 (1.0 wt%) prepared in Example 1, tested in a damp heat test chamber.

[0107] Figure 16 This is a comparison chart showing the corrosion of a blank sample of III+ base oil CTL4 and a sample of III+ base oil CTL4 with 1.0 wt% of benzothiazole amino acid ester derivative III-1-1 prepared in Example 5 of the present invention, tested in a damp heat test chamber. Detailed Implementation

[0108] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0109] It should be noted that the process equipment or apparatus not specifically mentioned in the following embodiments are all conventional equipment or apparatus in the art.

[0110] Furthermore, it should be understood that the existence of other method steps before or after the combined steps, or the insertion of other method steps between these explicitly mentioned steps, does not preclude the presence of other method steps before or after the combined steps, unless otherwise stated. It should also be understood that the combined connection relationship between one or more devices / apparatus mentioned in this invention does not preclude the existence of other devices / apparatus before or after the combined devices / apparatus, or the insertion of other devices / apparatus between these explicitly mentioned devices / apparatus. Moreover, unless otherwise stated, the numbering of each method step is merely a convenient tool for identifying each method step, and not for limiting the order of the method steps or defining the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0111] When numerical ranges are given in the embodiments, it should be understood that, unless otherwise stated in the present invention, both endpoints of each numerical range and any value between the two endpoints may be selected. Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art. In addition to the specific methods, apparatus, and materials used in the embodiments, based on the knowledge of the prior art possessed by one of ordinary skill in the art and the description of this invention, any prior art methods, apparatus, and materials similar to or equivalent to those described, apparatus, and materials in the embodiments of this invention may be used to implement the present invention.

[0112] The following compounds and intermediates were characterized by infrared spectroscopy (IR) and nuclear magnetic resonance (NMR). The starting materials and reagents used in the preparation of these compounds were available from suppliers or prepared by methods known to those skilled in the art. The following general synthetic routes are merely illustrative of methods by which the compounds of the present invention can be synthesized, and various modifications to these synthetic routes are possible and inspired by those skilled in the art who have referred to the disclosure of this invention.

[0113] In the example, the composition of the III+ base oil CTL4 is saturated isoalkanes, and the supplier is Shanxi Lu'an Group.

[0114] In this application, the experimental standards or specific procedures are as follows:

[0115] 1) Electrochemical workstation testing: using a saturated calomel electrode (SCE) and a platinum electrode (1×1 cm). 2 A standard three-electrode system was used, consisting of a working electrode and a carbon steel electrode. Tests were conducted in a 100 ml electrolytic cell. The steel surface of the working electrode needed to be ground to 2000# grit and thoroughly cleaned before testing. First, to stabilize the system, the three-electrode system was immersed in the sample solution for 30 minutes to obtain the open-circuit voltage (OCP). Subsequently, electrochemical impedance spectroscopy was performed under OCP. The sinusoidal signal was set to 5 mV, with a frequency range of 100 kHz - 0.01 Hz.

[0116] 2) Liquid Phase Corrosion Test: The liquid phase corrosion test is a commonly used method for testing the rust-preventive performance of industrial lubricating oils. Referring to GB / T 11143-2008 "Test Method for Rust Prevention Performance of Mineral Oils with Inhibitors in the Presence of Water", the steel rod is polished with 150 and 240 grit sandpaper, cleaned with petroleum ether, and dried. A beaker containing 300 ml of 1 wt.% rust-preventive oil is heated in a 60℃ constant temperature water bath. The steel rod is completely immersed in the rust-preventive oil for 30 minutes. A beaker containing 30 ml of rust-preventive oil and 30 ml of distilled water is placed in the liquid phase corrosion apparatus, a stirrer is added, and stirring is started, maintaining the beaker in the 60℃ water bath. The time it takes for the steel rod to rust is recorded; this is the liquid phase corrosion time. If the steel rod does not rust after 24 hours, the test is terminated.

[0117] 3) Damp heat test chamber test: The test shall be conducted in accordance with GB / T 2361-1992 "Damp heat test method for rust-preventive grease".

[0118] Example 1

[0119] This embodiment provides a specific benzothiazole amino acid ester derivative I-1-1, the structural formula of which is:

[0120] .

[0121] The preparation method is as follows:

[0122] 1) Preparation of the intermediate I-1-1 of the benzothiazole amino acid ester derivative: 1.0 eq of 2-chlorobenzothiazole, 20 mL of dimethyl sulfoxide, and 2.0 eq of sodium hydroxide were added to a 500 mL round-bottom flask. 1.0 eq of glycine was then added at room temperature to form a mixture. The mixture was stirred at 95 °C for 12 hours. After the reaction was complete, 50 mL of deionized water was added, and the resulting organic phase was a white solid obtained by filtration. The specific synthetic route is shown below:

[0123] .

[0124] The structure of the prepared benzothiazole amino acid ester derivative I-1-1 intermediate was characterized as follows:

[0125] 1H NMR (500 MHz, DMSO) δ 8.31 (s, 1H), 7.68 (d, J = 7.8 Hz, 1H), 7.41 (d, J = 8.0 Hz, 1H), 7.23 (t, J = 7.6 Hz, 1H), 7.04 (t, J = 7.5 Hz, 1H), 4.09(s, 3H).

[0126] The 1H NMR spectrum of the benzothiazole amino acid ester derivative I-1-1 intermediate is shown below. Figure 1 As shown.

[0127] 2) Preparation of benzothiazole amino acid ester derivative I-1-1: Dodecanol (5.78 g, 31.0 mmol), intermediate (5.38 g, 25.8 mmol), and p-toluenesulfonic acid (5.45 g, 31.0 mmol) were added to a 500 mL round-bottom flask. Toluene (100 mL) was added at room temperature to form a mixture, which was stirred at 150 °C for 12 hours. After the reaction was complete, 50 mL of deionized water was added to adjust the pH to 6, and the mixture was extracted with ethyl acetate. The reaction solution was then washed with water (200 mL) three times to separate the organic phase, which was dried with anhydrous sodium sulfate. Finally, the dried organic phase was concentrated under reduced pressure and subjected to column chromatography (eluent: petroleum ether / ethyl acetate, v / v = 90 / 10). The eluent obtained from the column chromatography was subjected to reduced pressure distillation to remove the solvent and dried under vacuum to obtain 9.71 g of white solid, with a yield of 62%. The specific synthetic route is shown below:

[0128] .

[0129] The structure of the prepared benzothiazole amino acid ester derivative I-1-1 was characterized as follows:

[0130] 1 H NMR (500 MHz, CDCl3) δ 7.47 (t, J = 8.8 Hz, 2H), 7.23-7.16 (m, 1H), 7.03- 6.97 (m, 1H), 6.22 (s, 1H), 4.21 (s, 2H), 4.10 (t, J = 6.7 Hz, 2H),1.56 (p, J = 6.7 Hz, 2H), 1.19 (d, J = 17.3 Hz, 18H), 0.80 (t, J = 6.9 Hz,3H) ppm.

[0131] IR (ATR): 3435.02, 2918.71, 2846.10, 1736.09, 1544.57, 1445.62, 1404.92, 1269.26, 1185.47, 1017.89, 953.26, 748.17, 721.84cm -1 .

[0132] The 1H NMR spectrum and IR spectrum of benzothiazole amino acid ester derivative I-1-1 are shown below. Figure 2 and Figure 3 As shown.

[0133] Example 2

[0134] In this embodiment, the benzothiazole amino acid ester derivative I-1-1 prepared in Example 1 above was added as a lubricating additive to III+ base oil CTL4 for anti-wear performance testing.

[0135] The benzothiazole amino acid ester derivative I-1-1 prepared in Example 1 was added to 200 mL of III+ base oil CTL4 at a dosage of 2 wt%, heated to 60 °C, and stirred for 30 min.

[0136] The wear scar diameters of a blank CTL4 sample of III+ base oil without any lubricating additives and a CTL4 sample of III+ base oil with added benzothiazole amino acid ester derivative I-1-1 were tested using a four-ball friction tester. The test conditions were: load 196 N, speed 1200 rpm, oil temperature 75℃, and test time 60 min. The wear scar diameter comparison is shown in Table 1. The data in Table 1 are the average wear scar diameters of the three balls. A comparison of the wear scar morphology of one ball is shown in [Table 1]. Figure 4 .

[0137] Table 1. Average wear scar diameter of blank sample and sample with benzothiazole amino acid ester derivative I-1-1

[0138]

[0139] Compared with the blank sample, the addition of benzothiazole amino acid ester derivative I-1-1 significantly reduced the wear scar to 0.42 mm, demonstrating excellent anti-wear performance.

[0140] Example 3

[0141] In this embodiment, the benzothiazole amino acid ester derivative I-1-1 prepared in Example 1 above was added as a lubricating additive to III+ base oil CTL4 for friction reduction performance testing.

[0142] The benzothiazole amino acid ester derivative I-1-1 prepared in Example 1 was added to 200 mL of III+ base oil CTL4 at a dosage of 1 wt%, heated to 60 °C, and stirred for 30 min.

[0143] The friction coefficients of a blank CTL4 sample of III+ base oil without any friction modifier and a CTL4 sample of III+ base oil with added benzothiazole I-1-1 were tested using a UMT friction testing machine. The test conditions were: load 5N, reciprocating frequency 2Hz, oil temperature 25℃, and 30min. The friction coefficient comparison curves are shown in [reference needed]. Figure 5 The average friction coefficients are compared in Table 2.

[0144] Table 2. Average coefficients of friction for blank samples and samples with benzothiazole amino acid ester derivative I-1-1

[0145]

[0146] Compared with the blank sample, the friction coefficient was reduced by 55.29% after adding benzothiazole amino acid ester derivative I-1-1, which showed excellent friction reduction performance.

[0147] Example 4

[0148] In this embodiment, the benzothiazole amino acid ester derivative I-1-1 prepared in Example 1 above was added as a lubricating additive to III+ base oil CTL4 for rust prevention performance testing.

[0149] The benzothiazole amino acid ester derivative I-1-1 prepared in Example 1 was added to 200 mL of III+ base oil CTL4 at a dosage of 1 wt%, heated to 60 °C, and stirred for 30 min.

[0150] Impedance comparison curves of CTL4 sample of III+ base oil without any friction modifier and CTL4 sample of III+ base oil with added benzothiazole I-1-1, tested using an electrochemical workstation, are shown below. Figure 6 .

[0151] Compared with the blank sample, the addition of benzothiazole amino acid ester derivative I-1-1 increased the radius of curvature of the impedance curve, showing good corrosion inhibition performance.

[0152] Example 5

[0153] This embodiment provides a specific benzothiazole amino acid ester derivative III-1-1, the structural formula of which is as follows:

[0154] .

[0155] The preparation method is as follows:

[0156] 1) Preparation of the intermediate benzothiazole amino acid ester derivative III-1-1: 1 eq of n-dodecyl alcohol and 1.2 eq of pyridine were added to a 500 mL round-bottom flask, followed by 100 mL of dichloromethane. Under ice bath conditions, 1.2 eq of bromoacetyl bromide was added dropwise to form a mixture. The mixture was stirred at 0 °C for 12 hours. After the reaction was complete, 30 g of the intermediate compound of this example was obtained by column chromatography, with a yield of 76%. The specific synthetic route is shown below:

[0157] .

[0158] The structure of the prepared benzothiazole amino acid ester derivative intermediate III-1-1 was characterized as follows:

[0159] 1 H-NMR (400 MHz, CDCl3) δ 4.61 (s, 2H), 4.15 (h, J = 6.4 Hz, 2H), 1.63 (p, J = 6.7 Hz, 2H), 1.27 (m, 18H), 0.87 (t, J = 6.9 Hz, 3H) ppm.

[0160] IR (ATR): 2925.2, 2854.4, 1740.2, 1465.5, 1281.1, 1163.4, 1111.0, 995.7, 721.6, 552.4 cm -1 .

[0161] The 1H NMR spectrum and IR spectrum of the benzothiazole amino acid ester derivative III-1-1 intermediate are shown below. Figure 7 and Figure 8 As shown.

[0162] 2) Preparation of benzothiazole amino acid ester derivative III-1-1: 2-aminobenzothiazole (2.97 g, 19.8 mmol), intermediate (6.07 g, 19.8 mmol), and cesium carbonate (7.08 g, 21.7 mmol) were added to a 500 mL round-bottom flask. N,N-dimethylformamide (50 mL) was added at room temperature to form a mixture, which was stirred at 50 °C for 12 hours. After the reaction, 50 mL of deionized water was added to adjust the pH to 5, and the mixture was extracted with ethyl acetate. The reaction solution was then washed with water (200 mL) three times consecutively to separate the organic phase, which was dried over anhydrous sodium sulfate. Finally, the dried organic phase was concentrated under reduced pressure and subjected to column chromatography (eluent: petroleum ether / ethyl acetate, v / v = 97 / 3). The eluent obtained from the column chromatography was subjected to reduced pressure distillation to remove the solvent and then dried under vacuum to obtain 6.94 g of a yellow solid, with a yield of 58%. The specific synthetic route is shown below:

[0163] .

[0164] The structure of the prepared benzothiazole amino acid ester derivative III-1-1 was characterized as follows:

[0165] 1H NMR (500 MHz, CDCl3) δ 7.57 (dd, J = 7.4, 5.2 Hz, 2H), 7.28 (t, J =7.7 Hz, 1H), 7.07 (t, J = 7.6 Hz, 1H), 4.40 (s, 4H), 4.15 (t, J = 6.6 Hz,4H), 1.62 (p, J = 6.5 Hz, 4H), 1.27 (dd, J = 23.6, 9.3 Hz, 37H), 0.88 (t, J =6.7 Hz, 6H). ppm.

[0166] IR (ATR): 3377.56, 2921.11, 2854.08, 1744.87, 1533.40, 1447.21,1183.08, 995.55, 745.78, 717.05 cm -1 .

[0167] The 1H NMR spectrum and IR spectrum of benzothiazole amino acid ester derivative III-1-1 are shown below. Figure 9 and Figure 10 As shown.

[0168] Example 6

[0169] In this embodiment, the benzothiazole amino acid ester derivative III-1-1 prepared in Example 5 above was added as a lubricating additive to III+ base oil CTL4 for anti-wear performance testing.

[0170] The benzothiazole amino acid ester derivative III-1-1 prepared in Example 5 above was added to 200 mL of III+ base oil CTL4 at an addition amount of 0.5 wt%, heated to 60 °C, and stirred for 30 min.

[0171] The wear scar diameters of a blank CTL4 sample of III+ base oil without any lubricating additives and a CTL4 sample of III+ base oil with benzothiazole amino acid ester derivative III-1-1 were tested using a four-ball friction tester. The test conditions were: load 196 N, speed 1200 rpm, oil temperature 75℃, and 30 min. The wear scar diameter comparison is shown in Table 3. The data in Table 3 are the average wear scar diameters of the three balls. The wear scar morphology comparison of one ball is shown in [Table 3]. Figure 11 .

[0172] Table 3. Average wear scar diameter of blank sample and sample with benzothiazole amino acid ester derivative III-1-1

[0173]

[0174] Compared with the blank sample, the addition of benzothiazole amino acid ester derivative III-1-1 significantly reduced the wear scar to 0.35 mm, demonstrating excellent anti-wear performance.

[0175] Example 7

[0176] In this embodiment, the benzothiazole amino acid ester derivative III-1-1 prepared in Example 5 above was added as a lubricating additive to III+ base oil CTL4 for friction reduction performance testing.

[0177] The benzothiazole amino acid ester derivative III-1-1 prepared in Example 5 above was added to 200 mL of III+ base oil CTL4 at an addition amount of 1 wt%, heated to 60 °C, and stirred for 30 min.

[0178] The friction coefficients of a blank CTL4 sample of III+ base oil without any friction modifier and a CTL4 sample of III+ base oil with added benzothiazole III-1-1 were tested using a UMT friction testing machine. The test conditions were: load 5N, reciprocating frequency 2Hz, oil temperature 25℃, and 30min. The friction coefficient comparison curves are shown in [reference needed]. Figure 12 The average friction coefficients are compared in Table 4.

[0179] Table 4. Average coefficients of friction for blank samples and samples with benzothiazole amino acid ester derivative III-1-1.

[0180]

[0181] Compared with the blank sample, the friction coefficient was reduced by 52.98% after adding benzothiazole amino acid ester derivative III-1-1, demonstrating excellent friction reduction performance.

[0182] Example 8

[0183] In this embodiment, the benzothiazole amino acid ester derivative III-1-1 prepared in Example 5 above was added as a lubricating additive to III+ base oil CTL4 for rust prevention performance testing.

[0184] The benzothiazole amino acid ester derivative III-1-1 prepared in Example 5 above was added to 200 mL of III+ base oil CTL4 at an addition amount of 1 wt%, heated to 60 °C, and stirred for 30 min.

[0185] Impedance comparison curves of the blank sample of III+ base oil CTL4 without any friction modifier and the sample of III+ base oil CTL4 with benzothiazole III-1-1 added, tested using an electrochemical workstation, are shown below. Figure 13 .

[0186] Compared with the blank sample, the radius of the capacitive arc increased after the addition of benzothiazole amino acid ester derivative III-1-1, showing good corrosion inhibition performance.

[0187] Example 9

[0188] In this embodiment, the benzothiazole amino acid ester derivative III-1-1 prepared in Example 5 above was added as a lubricating additive to III+ base oil CTL4 for rust prevention performance testing.

[0189] The benzothiazole amino acid ester derivative III-1-1 prepared in Example 5 above was added to 200 mL of III+ base oil CTL4 at an addition amount of 1 wt%, heated to 60 °C, and stirred for 30 min.

[0190] The rust prevention performance of a blank sample of CTL4 base oil without any lubricating additives and a sample of CTL4 base oil with benzothiazole amino acid ester derivative III-1-1 added was tested on a standard steel bar in a liquid phase corrosion test. A comparison of the rust conditions is shown below. Figure 14 .

[0191] Compared with the blank sample, after adding benzothiazole amino acid ester derivative III-1-1, the rust spots on the steel bar were significantly reduced, and there was almost no serious corrosion. III-1-1 showed excellent rust prevention performance.

[0192] Example 10

[0193] In this embodiment, the benzothiazole amino acid ester derivative I-1-1 prepared in Example 1 above was added as a lubricating additive to III+ base oil CTL4 for rust prevention performance testing.

[0194] The benzothiazole amino acid ester derivative I-1-1 prepared in Example 1 above was added to III+ base oil CTL4 at an addition amount of 1 wt%, heated to 60°C, and stirred for 30 min.

[0195] The rust prevention performance of a blank sample of CTL4 base oil without any lubricating additives and a sample of CTL4 base oil with benzothiazole amino acid ester derivative I-1-1 added was tested on No. 10 carbon steel using a damp heat test chamber. A comparison of rust conditions is shown in Table 5. Figure 15 Table 5 shows the time when the blank sample and the carbon steel plate No. 10 began to rust after the addition of benzothiazole amino acid ester derivative I-1-1. Figure 15 The corrosion status of carbon steel plate No. 10 after adding benzothiazole amino acid ester derivative I-1-1 is compared with that of blank sample and carbon steel plate No. 10 after the same time period.

[0196] Table 5. Time of rust initiation in blank sample and carbon steel plate after addition of benzothiazole amino acid ester derivative I-1-1

[0197]

[0198] Compared with the blank sample, after adding benzothiazole amino acid ester derivative I-1-1, it was observed that the time for rust spots to appear on the steel plate was significantly prolonged and the degree of rust was significantly reduced within the same time period. I-1-1 showed excellent rust prevention performance.

[0199] Example 11

[0200] In this embodiment, the benzothiazole amino acid ester derivative III-1-1 prepared in Example 5 above was added as a lubricating additive to III+ base oil CTL4 for rust prevention performance testing.

[0201] The benzothiazole amino acid ester derivative III-1-1 prepared in Example 5 above was added to III+ base oil CTL4 at a dosage of 1 wt%, heated to 60°C, and stirred for 30 min.

[0202] The rust prevention performance of a blank sample of CTL4 base oil without any lubricating additives and a sample of CTL4 base oil with benzothiazole amino acid ester derivative III-1-1 added were tested on No. 10 carbon steel plates using a damp heat test chamber. A comparison of rust conditions is shown in Table 6. Figure 16 Table 6 shows the time when the blank sample and the carbon steel plate No. 10 began to rust after the addition of benzothiazole amino acid ester derivative III-1-1. Figure 16 The corrosion status of carbon steel plate No. 10 after adding benzothiazole amino acid ester derivative III-1-1 is compared with that of blank sample and carbon steel plate No. 10 after the same time period.

[0203] Table 6. Time of rust initiation in blank sample and carbon steel plate after addition of benzothiazole amino acid ester derivative III-1-1.

[0204]

[0205] Compared with the blank sample, after adding benzothiazole amino acid ester derivative III-1-1, it was observed that the time for rust spots to appear on carbon steel plate No. 10 was significantly prolonged and the degree of rust was significantly reduced within the same time period. III-1-1 showed excellent rust prevention performance.

[0206] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any form or substance. It should be noted that those skilled in the art can make various improvements and additions without departing from the method of the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention. Any modifications, alterations, and equivalent changes made by those skilled in the art based on the above-disclosed technical content without departing from the spirit and scope of the present invention are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and evolutions made to the above embodiments based on the essential technology of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A benzothiazole amino acid ester derivative, characterized in that, The structural formula of the benzothiazole amino acid ester derivative is shown in Formula I, Formula II or Formula III: 、 、 ； Wherein, R1 is selected from H atoms or straight-chain or branched alkyl groups having 8 to 20 carbon atoms; R2 is selected from H, -CH(CH3)2, and -(CH2). n COOR1 , , , where n = 1-6.

2. The benzothiazole amino acid ester derivative according to claim 1, characterized in that, The benzothiazole amino acid ester derivative includes one or more of the following characteristics: Compounds of Formula I include: 、 、 ； Compounds of Formula II include: ； Compounds of Formula III include: 。 3. The benzothiazole amino acid ester derivative according to claim 2, characterized in that, The benzothiazole amino acid ester derivative includes one or more of the following characteristics: 、 、 、 、 。 4. A method for preparing benzothiazole amino acid ester derivatives as described in Formula I and Formula II as claimed in claim 1, characterized in that, The preparation method includes: using 2-chlorobenzothiazole and amino acids as reaction raw materials, and using a base as a catalyst, a substitution reaction is carried out to obtain carboxybenzothiazole amine; further, using carboxybenzothiazole amine as a raw material and reacting with an alkyl alcohol, an esterification reaction is carried out under the action of a catalyst to obtain benzothiazole amino acid ester derivatives of formula I and formula II.

5. The preparation method according to claim 4, characterized in that, The amino acid is one or more selected from alanine, glycine, aspartic acid, glutamic acid, serine, tryptophan, histidine, valine, tyrosine, or proline. And / or, the molar ratio of the 2-chlorobenzothiazole to the amino acid is 1:(1~1.6). And / or, the base catalyst is one or more of triethylamine, potassium carbonate, sodium carbonate, pyridine, or sodium hydroxide; And / or, the molar ratio of the 2-chlorobenzothiazole to the base catalyst is 1:(2~4). And / or, the alkyl alcohol is a straight-chain or branched alkyl alcohol having 8 to 20 carbon atoms; And / or, the molar ratio of the alkyl alcohol to carboxybenzothiazolamine is (1~2):1; And / or, the reaction temperature of the substitution reaction is 50-150°C; And / or, the substitution reaction further includes a reaction solvent, which is one or both selected from DMSO or DMF; And / or, the esterification reaction catalyst is one or more of p-toluenesulfonic acid, solid superacid, or cation exchange resin; And / or, the molar ratio of the esterification catalyst to the alkyl alcohol is (1~2):1; And / or, the esterification reaction further includes a reaction solvent, which is one or more of toluene, cyclohexane, or petroleum ether.

6. A method for preparing a benzothiazole amino acid ester derivative as described in Formula III as in claim 1, characterized in that, The preparation method includes: a first step reaction: using α-haloacyl halide and alkyl alcohol as reaction raw materials, a substitution reaction is carried out under the action of a catalyst to obtain an intermediate; a second step reaction: the obtained intermediate is further reacted with 2-aminobenzothiazole to prepare a benzothiazole amino acid ester derivative of formula III.

7. The preparation method according to claim 6, characterized in that, The α-haloacyl halide is one or more of fluoroacetyl chloride, bromoacetyl bromide, or chloroacetyl chloride; And / or, the alkyl alcohol is a straight-chain or branched alkyl alcohol having 8 to 20 carbon atoms; And / or, the molar ratio of the α-haloacyl halide to the alkyl alcohol is 1:(0.7~1); And / or, the catalyst for the first step reaction is one or more of pyridine, triethylamine, potassium carbonate, sodium carbonate, and diisopropylethylamine; And / or, the molar ratio of the catalyst to the alkyl alcohol in the first step reaction is 1:(1.0~1.5). And / or, the reaction temperature of the first step reaction is -5 to 5℃; And / or, the molar ratio of the intermediate to 2-aminobenzothiazole is (2~3):1; And / or, the preparation method further includes a reaction solvent, wherein the reaction solvent is one or more of dichloromethane, tetrahydrofuran, or N,N-dimethylformamide.

8. The use of a benzothiazole amino acid ester derivative as described in any one of claims 1 to 3 as an additive for lubricating oils or greases.

9. The application according to claim 8, characterized in that, The application includes at least one of the following 1) to 3): 1) Reduce the diameter of the wear scar; 2) Reduce friction; 3) Prevent or slow down rusting.

10. A lubricating oil and / or grease containing a benzothiazole amino acid ester derivative as described in any one of claims 1 to 3, characterized in that, The amount of the benzothiazole amino acid ester derivative added is 0.1-5.0 wt% based on the weight of the base oil and / or base grease.

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