Compounds based on benzimidazol-1-ylmethanol core and their preparation methods and applications

Abstract

The present invention discloses a compound based on a benzimidazole-1-ylmethanol core, a preparation method thereof, and an application thereof. The compound of the present invention has a structure shown in Formula I or Formula II: in Formula I, R is selected from 2-mercaptobenzothiazolyl, N-hydroxysuccinimide, N-(tert-butyloxycarbonyl)-toluenesulfonamide or tetrahydro-2H-pyran-2-hydroxyl; X is selected from O, S or N; in Formula II, R' is selected from at least one of thiophene sulfone, 2-sulfoxide benzothiazolyl and 4-nitrophthalimide. The compound of the present invention can prevent metal from being corroded in an alkaline environment and the pH value of the test solution does not decrease significantly. At the same time, the present invention can select suitable chemical reagents and chemicals to carry out structural modification on the compound based on "benzimidazole-1-ylmethanol" as the core to obtain compounds with different anti-corrosion properties to meet different application requirements.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal corrosion protection, and in particular relates to a compound based on an imidazole-1-ylmethanol core, a preparation method and an application thereof. Background Art

[0002] Metal corrosion is a phenomenon in which metals are destroyed by chemical or electrochemical effects of the environment. Metal corrosion affects all areas of marginal industrial production, causing huge economic losses and leading to an increase in the use of metal materials, which is not conducive to energy conservation, emission reduction and environmental protection.

[0003] Metal corrosion mainly includes two forms: electrochemical corrosion and seawater corrosion. Electrochemical corrosion is the damage caused by the electrochemical reaction between the metal surface and the ion-conducting medium. Its main characteristic is that its reaction process can be divided into two relatively independent and simultaneous processes: the cathodic reaction and the anodic reaction. Its main feature is the existence of a charged interface layer between the metal and the electrolyte. Seawater corrosion refers to the corrosion of equipment and facilities used in the marine environment. Seawater has the highest salt content and a complex composition, making it a corrosive electrolyte. The high concentration of chloride ions and other halide ions in seawater can prevent and destroy the passivation of metals, making the anodic process easier to proceed. Under the pH conditions of seawater, seawater corrosion is an oxygen depolarization process, and the cathodic process controls the speed of the corrosion reaction.

[0004] For a long time, people have been using a variety of technologies to protect metals. One of the most effective and economical methods is to apply an anti-corrosion coating to the metal surface to isolate the corrosive medium from the metal substrate. However, during its use, the coating will produce microcracks due to changes in factors such as the environment or mechanical properties. Due to exposure to the atmosphere, the microcracks will gradually spread and expand, thereby accelerating the peeling and delamination of the coating at the metal-coating interface, reducing the service life and anti-corrosion ability of the coating, and also affecting the use of the metal. Therefore, there is a need for a metal preservative that can prevent the corrosion of metal materials and solve the problems of metal anti-corrosion coatings in the existing technology that are prone to cracking, flaking, and poor anti-corrosion effect. Summary of the Invention

[0005] In order to improve the above technical problems, the present invention provides a compound based on a benzimidazol-1-ylmethanol core, a preparation method and an application thereof. The compound of the present invention can prevent metal corrosion in an alkaline environment and the pH value of the test liquid does not decrease significantly.

[0006] In order to achieve the above object, the present invention provides a compound having a structure represented by Formula I or Formula II:

[0007]

[0008] In formula I, R is selected from 2-mercaptobenzothiazolyl, N-hydroxysuccinimide, N-(tert-butyloxycarbonyl)-p-toluenesulfonamide or tetrahydro-2H-pyran-2-hydroxy; X is selected from O, S or N;

[0009] In formula II, R' is at least one selected from the group consisting of thiophenesulfone, 2-sulfoxidebenzothiazolyl, and 4-nitrophthalimide.

[0010] According to an embodiment of the present invention, the compound represented by formula I or formula II is selected from the following compounds:

[0011]

[0012]

[0013] The present invention also provides a method for preparing the compound of the structure represented by the above-mentioned Formula I or Formula II, its stereoisomers or pharmaceutically acceptable salts and hydrates, comprising reacting 1-chloromethyl-1H-benzimidazole with compound RX to obtain a compound of Formula I or Formula II; wherein: R and X have the definitions and selections as described above.

[0014] According to an embodiment of the present invention, the molar ratio of the 1-chloromethyl-1H-benzimidazole to the compound RX is 1:(1-5), exemplified by 1:1, 1:2, and 1:5.

[0015] According to an embodiment of the present invention, a base is preferably added during the reaction of 1-chloromethyl-1H-benzimidazole with compound RX.

[0016] Preferably, the molar ratio of the 1-chloromethyl-1H-benzimidazole to the base is 1:(1-5), exemplified by 1:1, 1:2.2, and 1:5.

[0017] Preferably, the base is selected from one, two or more of N,N-diisopropylethylamine (DIPEA), potassium carbonate, sodium tert-butoxide, potassium tert-butoxide, potassium phosphate and sodium acetate.

[0018] According to an embodiment of the present invention, NaI is preferably added during the reaction of 1-chloromethyl-1H-benzimidazole with compound RX.

[0019] Preferably, the molar ratio of the 1-chloromethyl-1H-benzimidazole to NaI is 1:(1-5), exemplified by 1:1, 1:2, and 1:5.

[0020] According to an embodiment of the present invention, the method for preparing the compound of the structure represented by Formula I or Formula II can be carried out in the presence of a solvent such as an organic solvent. For example, the organic solvent can be selected from 1,2-dichloroethane and tetrahydrofuran.

[0021] According to an embodiment of the present invention, the reaction temperature is 40-100°C, exemplified by 40°C, 60°C, 80°C, and 100°C; the reaction time is 1-48h, exemplified by 1h, 2h, 4h, 6h, 8h, 12h, 16h, 24h, 36h, and 48h.

[0022] According to an embodiment of the present invention, the preparation method further includes a step of isolating a solid product from the reaction mixture after the reaction is completed. For example, the solid product is obtained by spin-drying the solvent. Further, the preparation method also includes a step of purifying the product. For example, the purification can be performed by column chromatography. Preferably, the eluent for column chromatography separation is petroleum ether / ethyl acetate = (1 to 5): 1 (v / v), exemplified by 1:1, 2:1, and 5:1.

[0023] Preferably, the synthetic route of the compound of formula I or formula II is as follows:

[0024]

[0025] According to an embodiment of the present invention, the method for preparing the compound having the structure shown in Formula I or Formula II comprises the following steps:

[0026] (1) Under nitrogen protection, a nucleophilic reagent RX, 1-chloromethyl-1H-benzimidazole, sodium iodide, a base, and a solvent are stirred for reaction;

[0027] (2) After the reaction is completed, cool to room temperature and concentrate to remove the solvent;

[0028] (3) The crude product is purified by silica gel column chromatography using a mixed solvent of petroleum ether and ethyl acetate as eluent to obtain a compound represented by Formula I or Formula II.

[0029] According to an embodiment of the present invention, the 1-chloromethyl-1H-benzimidazole is prepared by a nucleophilic substitution reaction between 1-hydroxymethyl-1H-benzimidazole and a chlorinating agent.

[0030] In one embodiment of the present invention, the molar ratio of 1-hydroxymethyl-1H-benzimidazole to the chlorinating agent is 1:(1-10), exemplified by 1:1, 1:6, and 1:10.

[0031] In one embodiment of the present invention, the chlorinating agent is selected from thionyl chloride, phosphorus trichloride or phosphorus oxychloride.

[0032] In one embodiment of the present invention, the preparation method of 1-chloromethyl-1H-benzimidazole can be carried out in the presence of a solvent such as an organic solvent. For example, the organic solvent can be selected from chloroform.

[0033] According to an embodiment of the present invention, the reaction temperature is room temperature; the reaction time is 1 to 48 hours, exemplified by 1 hour, 2 hours, 4 hours, 6 hours, 8 hours, 12 hours, 16 hours, 24 hours, 36 hours, and 48 hours.

[0034] According to an embodiment of the present invention, the preparation method further comprises the step of separating the solid product from the reaction mixture after the reaction is completed. For example, the solid product is obtained by spin-drying the solvent.

[0035] According to an embodiment of the present invention, the 1-hydroxymethyl-1H-benzimidazole is prepared by reacting benzimidazole with formaldehyde.

[0036] In one embodiment of the present invention, the molar ratio of benzimidazole to formaldehyde is 1:(0.5-2), exemplified by 1:0.5, 1:1, and 1:2.

[0037] In one embodiment of the present invention, the preparation method of 1-hydroxymethyl-1H-benzimidazole can be carried out in the presence of a solvent such as an organic solvent. For example, the organic solvent can be selected from tetrahydrofuran.

[0038] In one embodiment of the present invention, the reaction temperature is room temperature; the reaction time is 1 to 48 hours, exemplified by 1 hour, 2 hours, 4 hours, 6 hours, 8 hours, 12 hours, 16 hours, 24 hours, 36 hours, and 48 hours.

[0039] In one embodiment of the present invention, the preparation method further comprises a step of isolating a solid product from the reaction mixture after the reaction is completed. For example, the solid product is obtained by spin-drying the solvent. Furthermore, the preparation method further comprises a step of purifying the product. For example, the purification can be performed by recrystallization. Preferably, the solvent for the recrystallization can be ethanol and water.

[0040] In one embodiment of the present invention, the synthetic route of 1-chloromethyl-1H-benzimidazole is as follows:

[0041]

[0042] The present invention also provides the use of the compound represented by the structure of Formula I or Formula II in cleaning and anti-corrosion of the surface of metal products.

[0043] The present invention also provides a detergent containing the compound having the structure shown in the above formula I or formula II.

[0044] The present invention also provides a preservative containing the compound having the structure shown in the above formula I or formula II.

[0045] According to an embodiment of the present invention, the preservative further comprises an auxiliary agent. Preferably, the auxiliary agent is selected from a sustained-release agent and / or a surfactant.

[0046] In one embodiment of the present invention, the sustained release agent is selected from triethanolamine borate.

[0047] In one embodiment of the present invention, the surfactant is 2-amino-2-methyl-propanol.

[0048] According to an embodiment of the present invention, the preservative further contains tetramethylammonium hydroxide.

[0049] According to an embodiment of the present invention, in the preservative, the mass of the compound of the structure represented by Formula I or Formula II is 0.01 to 20% of the mass of tetramethylammonium hydroxide, exemplified by 0.01%, 0.04%, 0.1%, 0.5%, 1%, 2%, 5%, 10%, 15%, and 20%.

[0050] The present invention also provides an anti-corrosion coating, which contains the compound with the structure shown in the above formula I or formula II and / or is prepared from the compound with the structure shown in the above formula I or formula II.

[0051] Beneficial effects of the present invention:

[0052] The present invention discloses a compound based on a benzimidazol-1-ylmethanol core, its preparation method, and its application. The compound can prevent metal corrosion in alkaline environments without significantly reducing the pH value of the test solution. Furthermore, the present invention allows for structural modification of the compound based on the benzimidazol-1-ylmethanol core by selecting suitable chemical reagents and pharmaceuticals to obtain compounds with varying anti-corrosion properties to meet different application requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 The 2-(((1H-benzo[d]imidazol-1-yl)methyl)thio)benzo[d]thiazole compound prepared in Example 1 1 H NMR spectrum.

[0054] Figure 2 The 2-(((1H-benzo[d]imidazol-1-yl)methyl)thio)benzo[d]thiazole compound prepared in Example 1 13 C NMR spectrum.

[0055] Figure 3 This is the HRMS spectrum of the 2-(((1H-benzo[d]imidazol-1-yl)methyl)thio)benzo[d]thiazole compound prepared in Example 1.

[0056] Figure 4The 1-((1H-benzimidazol-1-yl)methoxy)pyrrolidine-2,5-dione compound prepared in Example 2 1 H NMR spectrum.

[0057] Figure 5 The 1-((1H-benzimidazol-1-yl)methoxy)pyrrolidine-2,5-dione compound prepared in Example 2 13 C NMR spectrum.

[0058] Figure 6 This is the HRMS spectrum of the 1-((1H-benzimidazol-1-yl)methoxy)pyrrolidine-2,5-dione compound prepared in Example 2.

[0059] Figure 7 The 2-((1H-benzimidazol-1-yl)methyl)-5-nitroisoindoline-1,3-dione compound prepared in Example 3 1 H NMR spectrum.

[0060] Figure 8 The 2-((1H-benzimidazol-1-yl)methyl)-5-nitroisoindoline-1,3-dione compound prepared in Example 3 13 C NMR spectrum.

[0061] Figure 9 This is the HRMS spectrum of the 2-((1H-benzimidazol-1-yl)methyl)-5-nitroisoindoline-1,3-dione compound prepared in Example 3.

[0062] Figure 10 The tert-butyl ((1H-benzimidazol-1-yl)methyl)(toluenesulfonyl)carbamate compound prepared in Example 4 is 1 H NMR spectrum.

[0063] Figure 11 The tert-butyl ((1H-benzimidazol-1-yl)methyl)(toluenesulfonyl)carbamate compound prepared in Example 4 is 13 C NMR spectrum.

[0064] Figure 12 This is the HRMS spectrum of the ((1H-benzimidazol-1-yl)methyl)(tosyl)carbamic acid tert-butyl ester compound prepared in Example 4.

[0065] Figure 13 The 1-(((tetrahydro-2H-pyran-2-yl)oxy)methyl)-1H-benzimidazole compound prepared in Example 5 1 H NMR spectrum.

[0066] Figure 14 The 1-(((tetrahydro-2H-pyran-2-yl)oxy)methyl)-1H-benzimidazole compound prepared in Example 5 13 C NMR spectrum. DETAILED DESCRIPTION

[0067] The technical solutions of the present invention will be described in further detail below with reference to specific embodiments. It should be understood that the following embodiments are merely illustrative and explanations of the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are encompassed within the scope of protection that the present invention is intended to protect.

[0068] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.

[0069] In the following embodiments of the present invention, the preparation method of 1-chloromethyl-1H-benzimidazole is as follows:

[0070]

[0071] The preparation method of 1-chloromethyl-1H-benzimidazole comprises the following steps:

[0072] (1) Benzimidazole (10.0 g, 84.65 mmol) and tetrahydrofuran (250.0 mL) were added sequentially to a 250.0 mL reaction flask, followed by dropwise addition of formaldehyde solution (37% in H2O, 6.8 g, 84.65 mmol). The mixture was stirred at room temperature for 12 h.

[0073] (2) After stirring for 12 h, the components were concentrated on a rotary evaporator without any post-treatment;

[0074] (3) The crude product was recrystallized from ethanol and water and filtered to obtain a white solid (yield 64%), namely 1-hydroxymethyl-1H-benzimidazole, with the structural formula:

[0075] (4) 1-Hydroxymethyl-1H-benzimidazole (1.5 g, 10.0 mmol) and chloroform (50.0 mL) were added sequentially to a 250.0 mL reaction flask, followed by dropwise addition of thionyl chloride (7.1 g, 60.0 mmol), and the mixture was stirred at room temperature for 6 h.

[0076] (5) After stirring for 6 h, the components were concentrated on a rotary evaporator without any post-treatment to directly obtain the desired white solid (yield 89%), namely 1-chloromethyl-1H-benzimidazole, with the structural formula:

[0077]

[0078] Example 1

[0079] This embodiment provides a method for preparing 2-(((1H-benzo[d]imidazol-1-yl)methyl)thio)benzo[d]thiazole, and the reaction equation is as follows:

[0080]

[0081] A method for preparing 2-(((1H-benzo[d]imidazol-1-yl)methyl)thio)benzo[d]thiazole comprises the following steps:

[0082] (1) Under nitrogen protection, 2-mercaptobenzothiazole (1.67 g, 10.0 mmol), 1-chloromethyl-1H-benzimidazole (2.2 g, 11.0 mmol), sodium iodide (1.5 g, 10.0 mmol), potassium carbonate (3.0 g, 22.0 mmol), and 1,2-dichloroethane (50.0 mL) were added to a 250.0 mL reaction flask in sequence and stirred at 60°C for 16 h.

[0083] (2) After stirring for 16 h, the mixture was cooled to room temperature and concentrated on a rotary evaporator at 40 °C without any post-treatment;

[0084] (3) The crude product was purified by silica gel column chromatography using a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 2:1 as the eluent to obtain a white solid (yield: 60%), namely 2-(((1H-benzo[d]imidazol-1-yl)methyl)thio)benzo[d]thiazole, with the structural formula:

[0085] The basic parameters of the 2-(((1H-benzo[d]imidazol-1-yl)methyl)thio)benzo[d]thiazole compound prepared in this example are as follows:

[0086] 1 H NMR (400MHz, CDCl3) δ8.29(s,1H),7.98(d,J=8.1Hz,1H),7.79(m,1H),7.73(d,J=9.2Hz,1H),7.54-7.43(m,2H),7.37-7.28(m,3H),6.10(s,2H)( Figure 1 );

[0087] 13C NMR (101MHz, CDCl3) δ163.1,152.6,144.1,143.1,135.6,133.0,126.5,125.0,123.5,122.9,122.0,121.3,120.8,110.0,45.8( Figure 2 );

[0088] HRMS (ESI) m / z measured the 2-(((1H-benzo[d]imidazol-1-yl)methyl)thio)benzo[d]thiazole C prepared in this example 15 H 11 Molecular weight of N3S2 [M+H] + The theoretical molecular weight is 298.0467. Figure 3 ).

[0089] Example 2

[0090] This embodiment provides a method for preparing 1-((1H-benzimidazol-1-yl)methoxy)pyrrolidine-2,5-dione, and the reaction equation is:

[0091]

[0092] The preparation method of 1-((1H-benzimidazol-1-yl)methoxy)pyrrolidine-2,5-dione comprises the following steps:

[0093] (1) Under nitrogen protection, N-hydroxysuccinimide (1.16 g, 10.0 mmol), 1-chloromethyl-1H-benzimidazole (2.2 g, 11.0 mmol), sodium iodide (1.5 g, 10.0 mmol), N,N-diisopropylethylamine (DIPEA, 2.8 g, 22.0 mmol), and 1,2-dichloroethane (50.0 mL) were added to a 250.0 mL reaction flask in sequence and stirred at 60°C for 16 h.

[0094] (2) After stirring for 16 h, the mixture was cooled to room temperature and concentrated on a rotary evaporator without any post-treatment;

[0095] (3) The crude product was purified by silica gel column chromatography using a mixed solvent of ethyl acetate and methanol in a volume ratio of 100:1 as the eluent to obtain a white solid (yield: 60%), namely 1-((1H-benzimidazol-1-yl)methoxy)pyrrolidine-2,5-dione, with the structural formula:

[0096] The basic parameters of the 1-((1H-benzimidazol-1-yl)methoxy)pyrrolidine-2,5-dione compound prepared in this example are as follows:

[0097] 1 H NMR(400MHz, DMSO-d6)δ8.40(s,1H),7.70(dd,J=17.6,7.9Hz,2H),7.41-7.22(m,2H),6.11(s,2H),2.57(s,4H)( Figure 4 );

[0098] 13 C NMR (101MHz, DMSO-d6) δ171.6,144.8,143.5,133.7,123.2,122.5,119.6,110.5,77.2,25.4( Figure 5 );

[0099] HRMS (ESI) m / z measured the 1-((1H-benzimidazol-1-yl)methoxy)pyrrolidine-2,5-dione C prepared in this example 12 H 11 Molecular weight of N3O3 [M+H] + The theoretical molecular weight is 246.0873. Figure 6 ).

[0100] Example 3

[0101] This embodiment provides a method for preparing 2-((1H-benzimidazol-1-yl)methyl)-5-nitroisoindoline-1,3-dione, and the reaction equation is:

[0102]

[0103] The preparation method of 2-((1H-benzimidazol-1-yl)methyl)-5-nitroisoindoline-1,3-dione comprises the following steps:

[0104] (1) Under nitrogen protection, 4-nitrophthalimide (3.4 g, 10.0 mmol), 1-chloromethyl-1H-benzimidazole (2.2 g, 11.0 mmol), sodium iodide (1.5 g, 10.0 mmol), N,N-diisopropylethylamine (DIPEA, 2.8 g, 22.0 mmol), and 1,2-dichloroethane (50.0 mL) were added to a 250.0 mL reaction flask in sequence and stirred at 60°C for 16 h.

[0105] (2) After stirring for 16 h, the mixture was cooled to room temperature and concentrated on a rotary evaporator without any post-treatment;

[0106] (3) The crude product was purified by silica gel column chromatography using a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 1:1 as the eluent to obtain a yellow solid (yield: 60%), namely 2-((1H-benzimidazol-1-yl)methyl)-5-nitroisoindoline-1,3-dione, with the structural formula:

[0107] When potassium carbonate and potassium tert-butoxide were used instead of DIPEA, no 2-((1H-benzimidazol-1-yl)methyl)-5-nitroisoindoline-1,3-dione product was generated.

[0108] The basic parameters of the 2-((1H-benzimidazol-1-yl)methyl)-5-nitroisoindoline-1,3-dione compound prepared in this example are as follows:

[0109] 1 H NMR (400MHz, CDCl3) δ8.61(d,J=1.9Hz,1H),8.56(dd,J=8.1,2.0Hz,1H),8.21(s,1H),8.05(d ,J=8.2Hz,1H),7.74(d,J=8.0Hz,1H),7.68(d,J=7.9Hz,1H),7.34-7.19(m,2H),6.00(s,2H)( Figure 7 );

[0110] 13 C NMR (101MHz, CDCl3) δ165.3,165.0,152.0,143.9,143.4,135.8,132.8,132.7,129.9,125.3,123.9,123.0,120.4,119.3,110.2,45.6( Figure 8 );

[0111] HRMS (ESI) m / z measured the 2-((1H-benzimidazol-1-yl)methyl)-5-nitroisoindoline-1,3-dione C prepared in this example 16 H 10 Molecular weight of N4O4 [M+H] + is 323.0775, and its theoretical molecular weight is 323.0771( Figure 9 ).

[0112] Example 4

[0113] This embodiment provides a method for preparing tert-butyl ((1H-benzimidazol-1-yl)methyl)(tosyl)carbamate, and the reaction equation is:

[0114]

[0115] A method for preparing tert-butyl ((1H-benzimidazol-1-yl)methyl)(tosyl)carbamate comprises the following steps:

[0116] (1) Under nitrogen protection, N-(tert-butyloxycarbonyl)-p-toluenesulfonamide (2.7 g, 10.0 mmol), 1-chloromethyl-1H-benzimidazole (2.2 g, 11.0 mmol), sodium iodide (1.5 g, 10.0 mmol), potassium carbonate (3.0 g, 22.0 mmol), and tetrahydrofuran (50.0 mL) were added to a 250.0 mL reaction flask in sequence and stirred at 60°C for 14 h.

[0117] (2) After stirring for 14 h, the mixture was cooled to room temperature and concentrated on a rotary evaporator without any post-treatment;

[0118] (3) The crude product was purified by silica gel column chromatography using a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 1:3 as the eluent to obtain a white solid (yield: 63%), namely, tert-butyl ((1H-benzimidazol-1-yl)methyl)(tosyl)carbamate, with the structural formula:

[0119] The basic parameters of the tert-butyl ((1H-benzimidazol-1-yl)methyl)(tosyl)carbamate compound prepared in this example are as follows:

[0120] 1 H NMR (400MHz, CDCl3) δ8.25 (s, 1H), 7.83-7.72 (m, 2H), 7.31-7.21 (m, 5H), 7.04 (d, J = 10.2Hz, 2H), 6.19 (s, 2H), 2.28 (s, 3H), 1.29 (s, 9H) ( Figure 10 );

[0121] 13 C NMR (101MHz, CDCl3) δ150.5,144.7,144.4,143.2,136.0,133.0,129.2,127.4,123.5,122.6,120.1,110.9,86.1,53.1,27.6,21.4( Figure 11 );

[0122] HRMS (ESI) m / z measured the ((1H-benzimidazol-1-yl)methyl)(toluenesulfonyl)carbamic acid tert-butyl ester compound C prepared in this example 20 H 23 Molecular weight of N3O4S [M+H] +The theoretical molecular weight is 402.14820, and the theoretical molecular weight is 402.14763 ( Figure 12 ).

[0123] The preparation method is basically the same as the above, except that the base potassium carbonate is replaced by tBuOK and DIPEA in sequence. The experimental results show that:

[0124] When tBuOK was used as the base, the yield of tert-butyl ((1H-benzimidazol-1-yl)methyl)(tosyl)carbamate was 26%.

[0125] When DIPEA was used as the base, the yield of tert-butyl ((1H-benzimidazol-1-yl)methyl)(tosyl)carbamate was 78%.

[0126] Example 5

[0127] This embodiment provides a method for preparing 1-(((tetrahydro-2H-pyran-2-yl)oxy)methyl)-1H-benzimidazole, and the reaction equation is:

[0128]

[0129] The preparation method of 1-(((tetrahydro-2H-pyran-2-yl)oxy)methyl)-1H-benzimidazole comprises the following steps:

[0130] (1) Under nitrogen protection, 1-chloromethyl-1H-benzimidazole (1.1 g, 5.5 mmol), sodium iodide (0.75 g, 5.0 mmol), potassium tert-butoxide (1.2 g, 11.0 mmol), tetrahydrofuran (20.0 mL) solvent, and tetrahydro-2H-pyran-2-ol (0.51 g, 5.0 mmol) were added to a 250.0 mL reaction bottle in sequence and stirred at 60°C for 16 h.

[0131] (2) After stirring for 16 h, the mixture was cooled to room temperature and concentrated on a rotary evaporator at 40 °C without any post-treatment;

[0132] (3) The crude product was purified by silica gel column chromatography using a mixed solvent of petroleum ether and ethyl acetate in a volume ratio of 1:2 as the eluent to obtain a colorless oil (yield: 31%), namely 1-(((tetrahydro-2H-pyran-2-yl)oxy)methyl)-1H-benzimidazole, with the structural formula:

[0133] The basic parameters of the 1-(((tetrahydro-2H-pyran-2-yl)oxy)methyl)-1H-benzimidazole compound prepared in this example are as follows:

[0134] 1 H NMR (400MHz, CDCl3) δ8.05 (s, 1H), 7.80 (d, J = 7.1Hz, 1H), 7.56 (d, J = 6.6Hz, 1H), 7.39-7.27 (m, 2H), 5.74 (d, J = 11.4Hz, 1H),5.60(d,J=11.5Hz,1H),4.62(s,1H),3.80-3.67(m,1H),3.62–3.28(m,1H),1.83-1.71(m,1H),1.71-1.41(m,5H)( Figure 13 );

[0135] 13 C NMR (101MHz, CDCl3) δ143.54,143.50,133.8,123.7,122.9,120.3,110.3,95.4,69.8,62.4,29.8,25.2,18.8( Figure 14 ).

[0136] Test Example 1

[0137] Add 10.0g of DEV base (a 2.38% aqueous solution of tetramethylammonium hydroxide) to a 20.0mL Erlenmeyer flask. Add a magnet and start electromagnetic stirring to mix the solution evenly. Set the water bath temperature to 25-27°C. Then cut the aluminum sheet into 1cm*1cm small squares and place them in the Erlenmeyer flask. After soaking for 1 hour, remove the sheet with tweezers, rinse both sides with distilled water several times, wipe dry, and weigh. Then, place the sheet back in the solution and soak for another 2 hours (a total of 3 hours). After that, weigh the corroded weight and measure the pH of the solution at 18°C. The results are shown in Table 1 below.

[0138] Table 1

[0139]

[0140] Test Example 2

[0141] To a 20.0 mL Erlenmeyer flask, add 10.0 g of DEV base (a 2.38% aqueous solution of tetramethylammonium hydroxide), 0.2 g of additive 1 (triethanolamine borate sustained-release agent), and 0.01 g of additive 2 (2-amino-2-methyl-propanol surfactant). Add a magnetic stirrer and stir until the solution is evenly mixed. Set the water bath temperature to 25-27°C. Then, cut the aluminum sheet into 1 cm x 1 cm squares and place them in the Erlenmeyer flask. After soaking for 1 hour, remove the sheet with tweezers, rinse both sides several times with distilled water, wipe dry, and weigh. Then, place the sheet back in the solution and soak for another 2 hours (for a total of 3 hours). After that, weigh the corroded sheet. The pH of the solution was then measured at 18°C. The results are shown in Table 2 below.

[0142] Table 2

[0143]

[0144] Test Example 3

[0145] To a 20.0 mL Erlenmeyer flask, add 25.0 g of DEV base (a 2.38% aqueous solution of tetramethylammonium hydroxide), 0.15 g of additive 1 (triethanolamine borate sustained-release agent), 0.01 g of additive 2 (2-amino-2-methyl-propanol surfactant), and 0.2 g of the 2-(((1H-benzo[d]imidazol-1-yl)methyl)thio)benzo[d]thiazole complexing agent prepared in Example 1 (insoluble, dispersed in the system). A magnet was added, and electromagnetic stirring was activated to mix the solution evenly. The water bath temperature was set to 25-27°C. Subsequently, the aluminum sheet was cut into 1 cm*1 cm squares and placed in the Erlenmeyer flask. After soaking for 1 hour, the sheet was removed with tweezers, rinsed several times on both sides with distilled water, wiped dry, and weighed. The sheet was then placed back into the solution and soaked for another 2 hours (a total of 3 hours). The corroded weight was then weighed, and the pH of the solution was then measured at 18°C. The results are shown in Table 3 below.

[0146] Table 3

[0147]

[0148] Test Example 4

[0149] To a 20.0 mL Erlenmeyer flask, add 25.0 g of DEV base (a 2.38% aqueous solution of tetramethylammonium hydroxide), 0.2 g of additive 1 (triethanolamine borate sustained-release agent), 0.01 g of additive 2 (2-amino-2-methyl-propanol surfactant), and 0.15 g of the 1-((1H-benzimidazol-1-yl)methoxy)pyrrolidine-2,5-dione complexing agent prepared in Example 2 (insoluble, dispersed in the system). A magnet was added and electromagnetic stirring was activated to mix the solution evenly. The water bath temperature was set to 25-27°C. Subsequently, the aluminum sheet was cut into 1 cm x 1 cm squares and placed in the Erlenmeyer flask. After soaking for 1 hour, the sheet was removed with tweezers, rinsed several times on both sides with distilled water, wiped dry, and weighed. The sheet was then placed back into the solution and soaked for another 2 hours (a total of 3 hours). The corroded sheet was then weighed and the pH of the solution was measured at 18°C. The results are shown in Table 4 below.

[0150] Table 4

[0151]

[0152] Test Example 5

[0153] To a 20.0 mL Erlenmeyer flask, add 25.0 g of DEV base (a 2.38% aqueous solution of tetramethylammonium hydroxide), 0.15 g of additive 1 (triethanolamine borate sustained-release agent), 0.01 g of additive 2 (2-amino-2-methyl-propanol surfactant), and 0.04 g of the ((1H-benzimidazol-1-yl)methyl)(tosyl)carbamic acid tert-butyl ester complexing agent prepared in Example 4 (insoluble, dispersed in the system). A magnet was added, and electromagnetic stirring was activated to mix the solution evenly. The water bath temperature was set to 25-27°C. Subsequently, aluminum sheets were cut into 1 cm x 1 cm squares and placed in the Erlenmeyer flask. After soaking for 1 hour, the sheets were removed with tweezers, rinsed several times on both sides with distilled water, wiped dry, and weighed. The sheets were then placed back into the solution and soaked for another 2 hours (a total of 3 hours). The corroded sheets were then weighed and the pH of the solution was measured at 18°C. The results are shown in Table 5 below.

[0154] Table 5

[0155]

[0156] Test Example 6

[0157] In a 20.0 mL conical flask, 25.0 g of DEV base (aqueous solution of tetramethylammonium hydroxide at a concentration of 2.38%), 0.15 g of additive 1 (triethanolamine borate sustained-release agent), 0.01 g of additive 2 (2-amino-2-methyl-propanol surfactant), and 0.04 g of 1-(((tetrahydro-2H-pyran-2-yl)oxy)methyl)-1H-benzimidazole complexing agent prepared in Example 5 were added (small oil droplets did not dissolve). A magnet was added and electromagnetic stirring was turned on to mix the solution evenly. The water bath temperature was set to 25-27°C. Subsequently, the aluminum sheet was cut into small 1 cm*1 cm squares and placed in the conical flask. After soaking for 1 hour, it was removed with tweezers, rinsed several times on both sides with distilled water, wiped dry, and weighed. Then, it was placed in the solution again and soaked for another 2 hours (a total of 3 hours). The weight after corrosion was weighed and the pH value of the solution was then measured at 18°C. The measurement results are shown in Table 6 below.

[0158] Table 6

[0159]

[0160] Test Example 7

[0161] In a 20.0 mL conical flask, 25.0 g of DEV base (aqueous solution of tetramethylammonium hydroxide with a concentration of 2.38%), 0.2 g of additive 1 (triethanolamine borate sustained-release agent), 0.01 g of additive 2 (2-amino-2-methyl-propanol surfactant), and 0.03 g of 1-(((tetrahydro-2H-pyran-2-yl)oxy)methyl)-1H-benzimidazole complexing agent prepared in Example 5 were added (small oil droplets did not dissolve). A magnet was added and electromagnetic stirring was turned on to mix the solution evenly. The water bath temperature was set to 25-27°C. Subsequently, the aluminum sheet was cut into small 1 cm*1 cm squares and placed in the conical flask. After soaking for 1 hour, it was removed with tweezers, rinsed on both sides with distilled water several times, wiped dry, and weighed. Then it was placed in the solution again and soaked for another 2 hours (a total of 3 hours). The weight after corrosion was weighed and the pH value of the solution was then measured at 18°C. The measurement results are shown in Table 7 below.

[0162] Table 7

[0163]

[0164] Test Example 8

[0165] In a 20.0 mL conical flask, 10.0 g of DEV base (aqueous solution of tetramethylammonium hydroxide with a concentration of 2.38%), 0.15 g of additive 1 (triethanolamine borate sustained-release agent), 0.01 g of additive 2 (2-amino-2-methyl-propanol surfactant), and 0.2 g (completely dissolved) of the 1-((1H-benzimidazol-1-yl)methoxy)pyrrolidine-2,5-dione complexing agent prepared in Example 2 were added, a magnetic bar was added, electromagnetic stirring was turned on, the solution was mixed evenly, and the water bath temperature was set to 25-27°C. Subsequently, the aluminum sheet was cut into small squares of 1 cm*1 cm and placed in the conical flask. After soaking for 1 hour, it was removed with tweezers, rinsed on both sides with distilled water several times, wiped dry, and weighed. Then it was placed in the solution again, soaked for another 2 hours (a total of 3 hours), and the weight after corrosion was weighed. The pH value of the solution was then measured at 18°C. The measurement results are shown in Table 8 below.

[0166] Table 8

[0167]

[0168] Test Example 9

[0169] In a 20.0 mL conical flask, 10.0 g of DEV base (aqueous solution of tetramethylammonium hydroxide with a concentration of 2.38%), 0.2 g of additive 1 (triethanolamine borate sustained-release agent), 0.01 g of additive 2 (2-amino-2-methyl-propanol surfactant), and 0.15 g (completely dissolved) of the 1-((1H-benzimidazol-1-yl)methoxy)pyrrolidine-2,5-dione complexing agent prepared in Example 2 were added, a magnetic bar was added, electromagnetic stirring was turned on, the solution was mixed evenly, and the water bath temperature was set to 25-27°C. Subsequently, the aluminum sheet was cut into small squares of 1 cm*1 cm and placed in the conical flask. After soaking for 1 hour, it was removed with tweezers, rinsed on both sides several times with distilled water, wiped dry, and weighed. Then it was placed in the solution again, soaked for another 2 hours (a total of 3 hours), and the weight after corrosion was weighed. The pH value of the solution was then measured at 18°C. The measurement results are shown in Table 9 below.

[0170] Table 9

[0171]

[0172] Test Example 10

[0173] Take 10.0 g of each of the reference solutions I, II, III, and IV in Table 10 and add them to four conical flasks respectively. Then add 20.0 mg of the 1-((1H-benzimidazol-1-yl)methoxy)pyrrolidine-2,5-dione complexing agent prepared in Example 2 (completely dissolved). After dissolution, measure the pH value of the solution at 25-27°C; then cut the aluminum sheet into 1 cm*1 cm small squares and place them in the conical flask. After soaking for 1 hour, take it out with tweezers, rinse both sides with distilled water several times, wipe dry and weigh it; measure the pH value of the solution at 25-27°C. Then put it into the solution again, soak for another 2 hours (a total of 3 hours), weigh the weight after corrosion, and then measure the pH value of the solution at 25-27°C. The measurement results are shown in Tables 11 and 12 below.

[0174] Table 10

[0175] Reference Solution I DEV base 50g Additive 1 0.75g Additive 2 0.05g Reference Fluid II DEV base 50g Additive 1 1g Additive 2 0.05g Reference Solution III DEV base 50g - Additive 2 0.05g Reference Solution IV DEV base 50g - -

[0176] Note: “-” in the table means no addition; DEV base is a 2.38% aqueous solution of tetramethylammonium hydroxide, additive 1 is a triethanolamine borate sustained-release agent, and additive 2 is a 2-amino-2-methyl-propanol surfactant.

[0177] Table 11

[0178]

[0179] Note: Conditions Ⅰ, ⅠⅠ, ⅠⅠⅠ and ⅠV in the table correspond to the above-mentioned reference solution Ⅰ, reference solution ⅠⅠ and reference solution Ⅳ, respectively.

[0180] ⅠⅠⅠ, reference solution ⅣV.

[0181] Table 12

[0182]

[0183] Note: Conditions Ⅰ, ⅠⅠ, ⅠⅠⅠ and ⅠV in the table correspond to the above-mentioned reference solution Ⅰ, reference solution ⅠⅠ and reference solution Ⅳ, respectively.

[0184] ⅠⅠⅠ, reference solution ⅣV.

[0185] Test Example 11

[0186] In a 20.0 mL conical flask, 10.0 g of DEV base (aqueous solution of tetramethylammonium hydroxide at a concentration of 2.38%), 0.15 g of additive 1 (triethanolamine borate sustained-release agent), 0.01 g of additive 2 (2-amino-2-methyl-propanol surfactant), and 0.2 g (completely dissolved) of the 2-((1H-benzimidazol-1-yl)methyl)-5-nitroisoindoline-1,3-dione complexing agent prepared in Example 3 were added. A magnet was added and electromagnetic stirring was turned on to mix the solution evenly. The water bath temperature was set to 25-27°C. Subsequently, the aluminum sheet was cut into small 1 cm*1 cm squares and placed in the conical flask. After soaking for 1 hour, it was removed with tweezers, rinsed several times on both sides with distilled water, wiped dry, and weighed. Then, it was placed in the solution again and soaked for another 2 hours (a total of 3 hours). The weight after corrosion was weighed and the pH value of the solution was then measured at 18°C. The measurement results are shown in Table 13 below.

[0187] Table 13

[0188]

[0189] Test Example 12

[0190] In a 20.0 mL conical flask, 10.0 g of DEV base (aqueous solution of tetramethylammonium hydroxide at a concentration of 2.38%), 0.2 g of additive 1 (triethanolamine borate sustained-release agent), 0.01 g of additive 2 (2-amino-2-methyl-propanol surfactant), and 0.15 g (completely dissolved) of the 2-((1H-benzimidazol-1-yl)methyl)-5-nitroisoindoline-1,3-dione complexing agent prepared in Example 3 were added. A magnet was added and electromagnetic stirring was turned on to mix the solution evenly. The water bath temperature was set to 25-27°C. Subsequently, the aluminum sheet was cut into small 1 cm*1 cm squares and placed in the conical flask. After soaking for 1 hour, it was removed with tweezers, rinsed on both sides several times with distilled water, wiped dry, and weighed. Then it was placed in the solution again and soaked for another 2 hours (total 3 hours). The weight after corrosion was weighed and the pH value of the solution was then measured at 18°C. The measurement results are shown in Table 14 below.

[0191] Table 14

[0192]

[0193] Test Example 13

[0194] Take 10.0 g each of the reference solutions I, II, III, and IV in Table 10 above and add them to four conical flasks. Then add 20.0 mg of the 2-((1H-benzimidazol-1-yl)methyl)-5-nitroisoindoline-1,3-dione complexing agent prepared in Example 3 (completely dissolved). After dissolution, measure the pH value of the solution at 25-27°C. Then cut the aluminum sheet into small 1 cm*1 cm squares and place them in the conical flask. After soaking for 1 hour, remove it with tweezers, rinse both sides with distilled water several times, wipe dry, and weigh it; measure the pH value of the solution at 25-27°C. Then put it into the solution again, soak for another 2 hours (a total of 3 hours), weigh the weight after corrosion, and then measure the pH value of the solution at 25-27°C. The measurement results are shown in Tables 15 and 16 below.

[0195] Table 15

[0196]

[0197] Note: Conditions Ⅰ, ⅠⅠ, ⅠⅠⅠ and ⅠV in the table correspond to the above-mentioned reference solution Ⅰ, reference solution ⅠⅠ and reference solution Ⅳ, respectively.

[0198] ⅠⅠⅠ, reference solution ⅣV.

[0199] Table 16

[0200]

[0201]

[0202] Note: Conditions Ⅰ, ⅠⅠ, ⅠⅠⅠ and ⅠV in the table correspond to the above-mentioned reference solution Ⅰ, reference solution ⅠⅠ and reference solution Ⅳ, respectively.

[0203] ⅠⅠⅠ, reference solution ⅣV.

[0204] The above describes the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A compound having a structure shown in formula I: In formula I, R is selected from X is selected from O.

2. The method for preparing the compound of formula (I) according to claim 1, characterized in that: The preparation method comprises reacting 1-chloromethyl-1H-benzimidazole with a compound R-OH to obtain a compound of formula I; wherein: R has the definition and selection as described above.

3. The preparation method according to claim 2, wherein The molar ratio of the 1-chloromethyl-1H-benzimidazole to the compound R-OH is 1:(1-5).

4. The preparation method according to claim 2, wherein A base is added during the reaction between the 1-chloromethyl-1H-benzimidazole and the compound R-OH.

5. The preparation method according to claim 4, wherein The molar ratio of the 1-chloromethyl-1H-benzimidazole to the base is 1:(1-5); And / or, the base is one, two or more selected from N,N-diisopropylethylamine (DIPEA), potassium carbonate, sodium tert-butoxide, potassium tert-butoxide, potassium phosphate, and sodium acetate.

6. The preparation method according to claim 2, wherein NaI is added to the reaction between the 1-chloromethyl-1H-benzimidazole and the compound R-OH; And / or, the molar ratio of the 1-chloromethyl-1H-benzimidazole to NaI is 1:(1-5).

7. The preparation method according to claim 2, wherein The preparation method of the compound represented by the structure of Formula I is carried out in the presence of an organic solvent, and the organic solvent is selected from 1,2-dichloroethane and tetrahydrofuran.

8. The preparation method according to any one of claims 2 to 7, wherein The reaction temperature is 40-100° C.; the reaction time is 1-48 hours.

9. The preparation method according to any one of claims 2 to 7, wherein: The preparation method further comprises drying the solvent to obtain a solid product after the reaction is completed.

10. The preparation method according to claim 9, wherein The preparation method further comprises the step of purifying the product, wherein the purification is carried out by column chromatography separation; the volume ratio of the eluent for the column chromatography separation is petroleum ether / ethyl acetate=(1-5):

1.

11. The preparation method according to claim 10, characterized in that The method for preparing the compound of the structure shown in Formula I comprises the following steps: (1) Under nitrogen protection, a nucleophilic reagent R-OH, 1-chloromethyl-1H-benzimidazole, sodium iodide, a base, and a solvent are stirred to react; (2) After the reaction is completed, cool to room temperature and concentrate to remove the solvent; (3) The crude product was purified by silica gel column chromatography using a mixed solvent of petroleum ether and ethyl acetate as eluent to obtain a compound with the structure shown in Formula I.

12. Use of the compound of formula I according to claim 1 in cleaning and anti-corrosion of metal product surfaces.

13. A detergent, characterized in that It contains the compound with the structure shown in formula I according to claim 1.

14. A preservative, characterized in that It contains the compound with the structure shown in formula I according to claim 1.

15. The preservative according to claim 14, wherein The preservative further comprises an adjuvant, wherein the adjuvant is selected from a sustained-release agent and / or a surfactant; The sustained-release agent is selected from triethanolamine borate; The surfactant is 2-amino-2-methyl-propanol.

16. The preservative according to claim 15, wherein The preservative also contains tetramethylammonium hydroxide; In the preservative, the mass of the compound with the structure shown in Formula I is 0.01 to 20% of the mass of tetramethylammonium hydroxide.

17. An anti-corrosion coating, characterized in that: It contains the compound with the structure shown in formula I according to claim 1.

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