CN118344511A - Mannich base and preparation method and application thereof - Google Patents

Abstract

The invention provides a Mannich base and a preparation method and application thereof. The structure of the Mannich base is shown as a formula (I): In formula (I), R ₀ is selected from the group consisting of linear or branched alkylene of C _1～8; each R ₁, equal to or different from each other, is independently selected from the group consisting of linear or branched alkyl groups of H, C _1～4; each R ₁' is independently selected from the group consisting of linear or branched alkyl and phenyl of H, C _1～4; r ₂ is selected from hydrocarbon groups with the number average molecular weight Mn of 300-3000; r ₃ is selected from the group consisting of linear or branched alkyl of C _1～6. The Mannich base disclosed by the invention can be applied to gasoline, and has very excellent cleaning performance, deposit formation inhibition performance and rust prevention performance.

Description

A Mannich base and its preparation method and use

Technical Field

The invention relates to a gasoline detergent, in particular to a Mannich base detergent with a phenylenediamine structure.

Background technique

Gasoline fuel contains a large amount of unsaturated hydrocarbons and sulfur and nitrogen compounds. During storage and use, it is easy to come into contact with air and be oxidized into gum, which directly leads to the formation of carbon deposits and sediments in the electric nozzle, intake valve and combustion chamber during the fuel combustion process, causing problems such as poor fuel supply, air-fuel ratio imbalance, incomplete combustion, fuel waste, reduced engine efficiency, etc., and a large amount of harmful gases are emitted, which also increases the friction and wear between moving parts.

In order to solve the above-mentioned problems in the combustion process of gasoline, one or more multi-effect composite additives are usually added to the existing gasoline fuel to improve the performance of gasoline by utilizing the performance of different additives, while increasing the cleanliness and anti-oxidation properties of gasoline. Currently, the latest generation of detergents mainly use Mannich bases, which can effectively remove intake valve deposits.

US 20160289584A1 reports a mixture of Mannich alkaline detergents, including a first Mannich alkaline detergent component derived from a diamine or a polyamine and a second Mannich alkaline detergent component derived from a monoamine, but the synthesis method and cleaning performance of the diamine-type amine reported therein are not disclosed in the examples.

US 8557003B2 reports a Mannich base prepared from a polyamine containing primary amino groups, a hydroxy aromatic compound and an aldehyde, which has a good effect on removing intake valve deposits.

US 7384434B2 reports a Mannich base prepared by the reaction of hexahydrotriazine and a hydroxy aromatic compound. The reaction product has a similar structure to that synthesized using N,N-dimethyl-1,3-propylenediamine, but has many by-products and its purification effect needs to be improved.

GB 19592-2019 puts forward higher requirements on the cleanliness of gasoline. The existing technology still requires a Mannich base detergent with better cleaning performance, deposit formation inhibition performance and rust prevention performance.

Summary of the invention

The invention provides a Mannich base and a preparation method and application thereof.

The present invention includes the following aspects.

In a first aspect, the present invention provides a Mannich base.

The Mannich base of the present invention has a structure as shown in formula (I):

In formula (I), R ₀ is selected from a C _1-8 straight chain or branched alkylene group; each R ₁ is the same as or different from each other and is independently selected from H, a C _1-4 straight chain or branched alkyl group; each R ₁ ' is independently selected from H, a C _1-4 straight chain or branched alkyl group and a phenyl group; R ₂ is selected from a hydrocarbon group with a number average molecular weight Mn of 300 to 3000; R ₃ is selected from a C _1-6 straight chain or branched alkyl group.

According to the present invention, preferably, R ₀ is selected from a C _1-4 straight or branched alkylene group, each R ₁ is independently selected from H or methyl, each R ₁ ' is independently selected from H, methyl, R ₂ is selected from a polyisobutylene group with a number average molecular weight Mn of 500-2500; R ₃ is selected from a C _1-4 straight or branched alkyl group.

In a second aspect, the present invention provides a method for preparing a Mannich base.

The preparation method of the Mannich base of the present invention comprises reacting a compound represented by formula (X), a fatty aldehyde, and a compound represented by formula (Y), and collecting the product;

In formula (X), R ₂ is selected from a hydrocarbon group having a number average molecular weight Mn of 300 to 3000; R ₃ is selected from a C _{1 to 6} straight chain or branched alkyl group;

The carbon number of the fatty aldehyde is 1 to 8;

In formula (Y), each R ₁ is the same as or different from each other and is independently selected from H, a C _1-4 straight chain or branched alkyl group; each R ₁ ′ is independently selected from H, a C _1-4 straight chain or branched alkyl group and a phenyl group.

According to the present invention, preferably, in formula (X), R ₂ is selected from a polyisobutylene group having a number average molecular weight Mn of 500 to 2500, R ₃ is selected from a C _{1 to 4} straight chain or branched alkyl group; the carbon number of the fatty aldehyde is 1 to 4; in formula (Y), each R ₁ is independently selected from H or methyl, and each R ₁ ' is independently selected from H or methyl.

According to the present invention, the compound represented by formula (X) can be prepared by alkylation reaction of phenol and/or mono-ortho-C _1-6 alkylphenol with polyolefin. The alkylation reaction can refer to the alkylation reaction method proposed in CN103664655A.

According to the present invention, the fatty aldehyde is preferably formaldehyde or acetaldehyde, more preferably formaldehyde, and the formaldehyde can be formaldehyde solution, paraformaldehyde or oligoformaldehyde.

According to the present invention, the compound represented by formula (Y) can be selected from one or more of p-phenylenediamine, 2-methyl-p-phenylenediamine, tetramethyl-p-phenylenediamine, N,N-dimethyl-1,4-phenylenediamine, N-ethyl-p-phenylenediamine, N,N-diethyl-p-phenylenediamine and N,N-diethyl-3-methyl-p-phenylenediamine.

According to the present invention, the molar ratio of the compound represented by formula (X), the fatty aldehyde, and the compound represented by formula (Y) is preferably 1:0.1-3.5:0.3-3.

According to the present invention, the temperature for the reaction between the compound represented by formula (X), the fatty aldehyde and the compound represented by formula (Y) is 50°C to 200°C, preferably 80°C to 180°C, and most preferably 90°C to 160°C.

According to the present invention, the reaction time between the compound represented by formula (X), the fatty aldehyde and the compound represented by formula (Y) is generally as long as possible, generally 1h to 10h, preferably 2h to 8h, and most preferably 3h to 6h.

According to the present invention, a solvent may be added during the reaction of the compound represented by formula (X), the fatty aldehyde, and the compound represented by formula (Y), and the solvent is selected from hydrocarbons with a boiling point between 100°C and 160°C, such as toluene, xylene, and No. 150 solvent gasoline, and the amount of the solvent added may be 2% to 80% of the mass of the compound represented by formula (X), preferably 10% to 70%. The solvent may be removed by a method known in the art after the reaction is completed, such as a vacuum distillation method.

According to the present invention, a diluent may be added to the reaction of the compound represented by formula (X), the fatty aldehyde, and the compound represented by formula (Y), and the diluent may be one or more of a mineral lubricant, a polyolefin, and a polyether. The mineral lubricant may be selected from API I, II, and III mineral lubricants, preferably mineral lubricants with a viscosity of 20 to 120 centistokes at 40°C and a viscosity index of more than 50; the polyolefin is a polyolefin obtained by polymerizing ethylene, propylene, and α-olefins alone or in combination, and the α-olefin includes one or more of n-butene, isobutylene, n-pentene, n-hexene, n-octene, and n-decene, preferably a poly-α-olefin with a viscosity of 2 to 25 centistokes at 100°C; the polyether is a polymer generated by the reaction of an alcohol and an epoxide, the alcohol is ethylene glycol and/or 1,3-propylene glycol, the epoxide is ethylene oxide and/or propylene oxide, and the number average molecular weight of the polyether is 500 to 3000, preferably 700 to 3000. After the reaction of the compound represented by formula (X), the fatty aldehyde, and the compound represented by formula (Y) is completed, the diluent can be separated and removed, or the diluent can be retained in the reaction product. In this case, the reaction product is a composition comprising a Mannich base and a diluent, which can be added to gasoline for use as a detergent concentrate. The detergent concentrate can also be obtained by mixing the prepared Mannich base product with a diluent at 20° C. to 60° C. for 1 h to 6 h.

The Mannich base proposed in the first aspect or the Mannich base prepared according to the method of the second aspect can be used in gasoline and has very excellent cleaning performance, deposit generation inhibition performance and rust prevention performance.

In a third aspect, the present invention proposes the use of the Mannich base proposed in the first aspect and the use of the Mannich base prepared according to the method of the second aspect.

The Mannich base can be used as a gasoline detergent.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a comparative infrared spectra of the high-activity polyisobutylene raw material and the polyisobutylene-based o-methylphenol product in Example 1, wherein the upper figure (1) is the infrared spectrum of the high-activity polyisobutylene, and the lower figure (2) is the infrared spectrum of the polyisobutylene-based o-methylphenol product.

FIG. 2 is a high-field portion of the nuclear magnetic resonance hydrogen spectrum (1H NMR) of the polyisobutylene-o-methylphenol product in Example 1.

FIG. 3 is a low-field portion of the nuclear magnetic resonance hydrogen spectrum (1H NMR) of the polyisobutylene-o-methylphenol product in Example 1.

FIG. 4 is an infrared spectrum of the product of Example 2.

FIG5 is a hydrogen nuclear magnetic resonance spectrum of the product of Example 2.

FIG6 is an infrared spectrum of the product of Comparative Example 1.

FIG. 7 is a hydrogen nuclear magnetic resonance spectrum of the product of Comparative Example 1.

Detailed ways

The present invention is further described below by way of examples, but they are not intended to limit the present invention.

The comparative examples all adopt the main method for synthesizing Mannich bases reported in current patent literature.

The main raw materials used are as follows: o-cresol, AR, a product of Shanghai Aladdin Biochemical Technology Co., Ltd.; high-activity polyisobutylene (HRPIB, Mn≈1000), a product of Yangzi Petrochemical-BASF Co., Ltd.; n-hexane, GC, a product of Beijing Inokai Technology Co., Ltd.; toluene, AR, a product of Beijing Inokai Technology Co., Ltd.; xylene, AR, a product of Tianjin Fuyu Fine Chemical Co., Ltd.; commercial gasoline detergent 6416, Afton Chemical Corporation; anhydrous methanol, AR, a product of Tianjin Damao Chemical Reagent Factory; formaldehyde aqueous solution, 37%, Thermo Fisher Scientific Products of Beijing Inokai Technology Co., Ltd. (China); boron trifluoride etherate, Beijing Inokai Technology Co., Ltd.; p-phenylenediamine, N,N-dimethyl-1,4-phenylenediamine, GC, Shanghai Aladdin Biochemical Technology Co., Ltd.; ethylenediamine, AR, Beijing Inokai Technology Co., Ltd.; S150 aromatic solvent, polyether, Beijing Xingpu Fine Chemical Technology Development Co., Ltd.; N,N-dimethyl-1,3-propylenediamine, AR, Beijing Inokai Technology Co., Ltd.; 1,3,5-tris(dimethylaminopropyl)-1,3,5-hexahydrotriazine, AR, Beijing Inokai Technology Co., Ltd.

Example 1 Synthesis of polyisobutylene o-methylphenol

In a 1L reactor equipped with a stirrer, _N2 inlet tube, thermocouple thermometer, spherical condenser and feed pump, 64.96g (0.601mol) o-cresol, 12.88g (0.091mol) boron trifluoride ether catalyst, 215.03g n-hexane solvent and 300.91g (0.300mol) polyisobutylene (Mn = 1000) were added and reacted at 30°C for 6h. After the reaction, 64ml of deionized water was added, transferred to a 1L separatory funnel, and then 160ml of methanol was added. After shaking, the mixture was allowed to stand for 1h to separate the layers. After separating the lower layer of liquid, the mixture was repeated twice. The upper layer of liquid was distilled under reduced pressure to obtain a light yellow polyisobutylene o-cresol product. The F content in the product was less than 1ppm by elemental analysis, the o-cresol content was less than 0.006% by GC-MS analysis, and the yield of polyisobutylene o-cresol was 99% by oxygen element content analysis.

FIG1 is a comparative infrared spectra of the high-activity polyisobutylene raw material and the polyisobutylene-based o-methylphenol product in Example 1, wherein the upper figure (1) is the infrared spectrum of the high-activity polyisobutylene, and the lower figure (2) is the infrared spectrum of the polyisobutylene-based o-methylphenol product.

As shown in Figure 1, after the alkylation reaction, the characteristic peaks of the highly active polyisobutylene (HRPIB) that disappear are: 3070 cm ^-1 (asymmetric stretching vibration of the terminal α-olefin CH bond) and 1640 cm ^-1 (stretching vibration of the terminal α-methylene C=C double bond). The characteristic absorption peaks of the synthesized polyisobutylene o-methylphenol are: 3620 cm ^-1 (stretching vibration peak of the free phenolic hydroxyl group OH without an associating agent, with a sharp peak shape), 3500-3200 cm ^-1 (stretching vibration of the phenolic hydroxyl group OH after intermolecular hydrogen bonding, which is a broad absorption peak), 1605 cm ^-1 and 1505 cm ^-1 (two absorption bands of skeleton vibration of mononuclear aromatic C=C double bond), 1262 cm ^-1 (stretching vibration absorption peak of Ar-O on the benzene ring) and 818 cm ^-1 (out-of-plane bending vibration of CH on the benzene ring when the benzene ring is 1,2,4 substituted).

Figure 2 is the high field portion of the nuclear magnetic resonance hydrogen spectrum (1H NMR) of the polyisobutenyl o-methylphenol product in Example 1. Figure 3 is the low field portion of the nuclear magnetic resonance hydrogen spectrum (1H NMR) of the polyisobutenyl o-methylphenol product in Example 1.

It can be seen from Figures 2 and 3 that at the chemical shift of 2.261, there is a characteristic peak of methyl hydrogen on the benzene ring of polyisobutenyl o-methylphenol; at the chemical shift of 4.561, there is a characteristic peak of hydroxyl hydrogen on the benzene ring of polyisobutenyl o-methylphenol; the integral of methyl hydrogen is defined as 3, and the integral ratio of hydrogen, hydroxyl hydrogen and methyl hydrogen on the benzene ring is 0.98:0.99:0.98:0.97:3.00, which is close to the theoretical value of 1:1:1:1:3. Therefore, it can be seen from the nuclear magnetic resonance analysis that the target product polyisobutenyl o-methylphenol has been prepared.

An exemplary reaction equation for Example 1 is as follows.

Example 2 Synthesis of Mannich Base

In a four-necked flask equipped with a _N2 inlet tube, a thermocouple thermometer, a spherical condenser and a feed pump, 55.11 g of the polyisobutylene-o-methylphenol in Example 1, 56.03 g of xylene and 6.14 g of N,N-dimethyl-1,4-phenylenediamine were added, 4.89 g of a 37% formaldehyde aqueous solution was added dropwise, the temperature was raised to 150°C and the reaction was carried out for 3 hours. After the reaction was completed, the Mannich base of the present invention was obtained by distillation under reduced pressure.

Fig. 4 is an infrared spectrum of the product of Example 2. As shown in Fig. 4, the characteristic peaks generated after the synthesis of the Mannich base are: 3500-3300 cm ^-1 (NH stretching vibration, overlapping with OH stretching vibration, the peak shape is further broadened), 1749.35 cm ^-1 (overtone band of CH out-of-plane bending vibration of benzene ring when 1, 2, 4, 6 substitution occurs), 1162.11 cm ^-1 and 1056.47 cm ^-1 (aliphatic amine CN stretching vibration), 871.49 cm ^-1 (CH out-of-plane bending vibration of benzene ring when 1, 2, 4, 6 substitution occurs).

FIG5 is a hydrogen nuclear magnetic resonance spectrum of the product of Example 2.

As shown in Figure 5, the chemical shift of 5.23 in the NMR spectrum of the Mannich product is the proton hydrogen on the secondary amine group of N,N-dimethyl-1,4-phenylenediamine that undergoes the Mannich reaction, the chemical shift of 4.47 is the displacement peak of the hydrogen proton on the methylene group generated by the conversion of the formaldehyde carbonyl group, and the chemical shift of 2.84 is the methyl proton peak of N,N-dimethyl-1,4-phenylenediamine. The area ratio of the three is 1:1.99:6.03, which is consistent with the theoretical area ratio. In addition, the low field is more chaotic because the peaks of the two benzene rings overlap each other, but it can still be seen that the high-field benzene ring peak is the benzene ring on N,N-dimethyl-1,4-phenylenediamine, and the area is consistent with the ratio. The chemical shift peak of the hydroxyl group on the benzene ring disappears because the content of the hydroxyl group in the entire chemical molecule is very low, and some of the hydroxyl groups participate in the reaction, which further reduces the content of the hydroxyl group, resulting in the disappearance of the chemical shift peak of the hydroxyl proton, which shows that there are fewer by-products.

Oxygen content analysis gave a yield of 84%.

An exemplary reaction equation for Example 2 is as follows.

Example 3

In a four-necked flask equipped with a _N2 inlet tube, a thermocouple thermometer, a spherical condenser and a feed pump, 33.14 g of the polyisobutylene-o-methylphenol in Example 1, 34.91 g of toluene solvent and 3.34 g of p-phenylenediamine were added, and 2.92 g of a 37% formaldehyde aqueous solution was added dropwise at a flow rate of 0.06 ml/min. The temperature was raised to 90°C and the reaction was carried out for 3 hours. After the reaction was completed, the Mannich base of the present invention was obtained by distillation under reduced pressure.

An exemplary reaction equation for Example 3 is as follows.

Comparative Example 1

In a four-necked flask equipped with a _N2 inlet tube, a thermocouple thermometer, a spherical condenser and a feed pump, 55.11 g of polyisobutylene o-methylphenol and 56.03 g of xylene in Example 1 were added, the temperature was raised to 45°C, 5.17 g of 1,3,5-tris(dimethylaminopropyl)-1,3,5-hexahydrotriazine was added, the temperature was raised to 140°C, the reaction was carried out for 4 hours, and a comparative detergent product was obtained by distillation under reduced pressure.

FIG6 is an infrared spectrum of the product of Comparative Example 1.

As shown in Figure 6, the characteristic peaks produced after the synthesis of the Mannich base are: 3500-3300 cm ^-1 (NH stretching vibration, overlapping with OH stretching vibration, the peak shape is further broadened), 1748.64 cm ^-1 (NH bending vibration peak of secondary amine), 1015.76 cm ^-1 (CN stretching vibration peak).

FIG. 7 is a hydrogen nuclear magnetic resonance spectrum of the product of Comparative Example 1.

As shown in Figure 7, the chemical shifts of the benzene ring are complex and there are multiple structures. The chemical shifts 4.82 and 3.92 are the hydrogen proton shift peaks of the secondary amine group -NH- in different structures, the chemical shift 3.61 is the shift peak of the hydrogen proton on the methylene generated by the conversion of the formaldehyde carbonyl group, and the chemical shift 2.71 is the shift peak of the methylene connected to the amine group that undergoes the Mannich reaction.

From the infrared spectrum and hydrogen nuclear magnetic resonance spectrum of comparative example 1, it can be seen that there are bis-Mannich and cyclo-Mannich by-products in the comparative example, which is consistent with the report in US7384434B2.

An exemplary reaction equation for Comparative Example 1 is as follows.

Comparative Example 2

In a four-necked flask equipped with a _N2 inlet tube, a thermocouple thermometer, a spherical condenser and a feed pump, 38.14 g of polyisobutylene o-cresol, 38.13 g of xylene and 3.29 g of N,N-dimethyl-1,3-propylenediamine in Example 1 were added, 3.44 g of a 37% formaldehyde aqueous solution was added dropwise, the temperature was raised to 150°C and the reaction was carried out for 3 hours. After the reaction was completed, the comparative detergent product was obtained by distillation under reduced pressure.

An exemplary reaction equation for Comparative Example 2 is as follows.

Comparative Example 3

In a four-necked flask equipped with a _N2 inlet tube, a thermocouple thermometer, a spherical condenser and a feed pump, 33.12 g of the polyisobutylene-o-methylphenol in Example 1, 35.7 g of toluene solvent and 1.64 g of ethylenediamine were added, and 2.89 g of a 37% formaldehyde aqueous solution was added dropwise at a flow rate of 0.06 ml/min. The temperature was raised to 110°C and the reaction was carried out for 3 hours. After the reaction was completed, the Mannich base of the present invention was obtained by distillation under reduced pressure.

An exemplary reaction equation for Comparative Example 3 is as follows.

Example 4

300 ppm (about 0.0673 g) of the Mannich base or comparative detergent (including the comparative Mannich base of comparative examples 1 to 3 and 6416 commercial comparative agent) and 300 ppm of polyether base oil were added to 300 ml of 95 ^# gasoline meeting the National VI standard, and the mixture was mixed to prepare a gasoline composition containing the Mannich base detergent.

Example 5 Cleaning Performance Evaluation

740 μl of dicyclopentadiene coking agent was added to the gasoline composition of Example 4 and blank gasoline respectively, and the cleaning performance of the Mannich base of the present invention and the comparative detergent was evaluated using an L-2 intake valve deposit simulation tester produced by Lanzhou Weike Petrochemical Instrument Co., Ltd. according to GB/T 37322-2019 “Test method for simulation of gasoline engine intake valve deposits for evaluation of gasoline detergency”.

The specific operation method is as follows:

After weighing and recording the dry sediment collector and the reference plate twice and taking the average value, the sediment collector is loaded into the test equipment and clamped to conduct a cleaning performance evaluation test. The test time is 85 minutes, the oil injection time is 75 minutes, the test temperature is 175°C, and the temperature control accuracy is ±1°C. After connecting the air source, the air pressure is 80kPa±1kPa, and the air flow rate is 700L/h±20L/h. After the test, the sediment collector is taken out with tweezers, cooled to room temperature, placed in a container filled with n-heptane and soaked for 6 minutes, then taken out, placed in a container filled with petroleum ether (60℃～90℃), soaked for 1 minute, then taken out, and a paper stick is inserted into the temperature measuring hole of the collector to absorb the reagent in the hole, weigh the weight of the collector, and calculate the mass of the sediment. The sediment cleaning effect is shown in Table 1.

Table 1

Detergent Sediment volume Sediment decline rate blank 9.0mg - Example 2 1.10mg 87.78% Example 3 1.27mg 85.88% Comparative Example 1 2.02mg 77.56% Comparative Example 2 1.56mg 82.67% Comparative Example 3 1.78mg 80.22% 6416 Commercial contrast agent 1.43mg 84.11%

Example 6 Evaluation of rust prevention performance

The anti-rust performance of gasoline detergents was evaluated using the GB/T19230.1-2003 gasoline detergent anti-rust performance test method. This method involves completely immersing a cylindrical test rod in a mixture of 30 ml of test gasoline and 30 ml of distilled water under stirring conditions at a temperature of (38±1)°C for 4 hours to observe the degree of corrosion of the test rod.

The classification for evaluating the degree of corrosion is as follows:

Mild rust: limited to no more than 6 rust spots, and the diameter of each rust spot is less than or equal to 1mm.

Moderate rust: There are more than 6 rust spots, but less than 5% of the surface area of the test bar.

Severe rust: Rust spots exceed 5% of the test bar surface area.

The anti-rust performance of the Mannich base or comparative detergent of the examples and the blank samples was evaluated. The test results are shown in Table 2.

Table 2

Detergent Added dose/mg/kg Degree of rust blank - serious Example 2 100 Mild Example 3 100 Mild Comparative Example 1 100 Moderate Comparative Example 2 100 Moderate Comparative Example 3 100 Moderate 6416 Commercial contrast agent 100 Moderate

Claims (10)

1. Mannich base, the structure of which is shown in formula (I): In formula (I), R ₀ is selected from a C _1-8 straight chain or branched alkylene group; each R ₁ is the same as or different from each other and is independently selected from H, a C _1-4 straight chain or branched alkyl group; each R ₁ ' is independently selected from H, a C _1-4 straight chain or branched alkyl group and a phenyl group; R ₂ is selected from a hydrocarbon group with a number average molecular weight Mn of 300 to 3000; R ₃ is selected from a C _1-6 straight chain or branched alkyl group. 2. The Mannich base according to claim 1, characterized in that R ₀ is selected from a C _1-4 straight chain or branched alkylene group, each R ₁ is independently selected from H or methyl, each R ₁ ' is independently selected from H, methyl, R ₂ is selected from a polyisobutylene group with a number average molecular weight Mn of 500 to 2500; and R ₃ is selected from a C _1-4 straight chain or branched alkyl group. 3. A method for preparing a Mannich base, comprising reacting a compound represented by formula (X), a fatty aldehyde, and a compound represented by formula (Y), and collecting the product; In formula (X), R ₂ is selected from a hydrocarbon group having a number average molecular weight Mn of 300 to 3000; R ₃ is selected from a C _{1 to 6} straight chain or branched alkyl group; The carbon number of the fatty aldehyde is 1 to 8; In formula (Y), each R ₁ is the same as or different from each other and is independently selected from H, C _1-4 linear or branched alkyl; each R ₁ ′ is independently selected from H, C _1-4 linear or branched alkyl and phenyl. 4. The method according to claim 3, characterized in that, in formula (X), _R2 is selected from polyisobutylene with a number average molecular weight Mn of 500 to 2500, _R3 is selected from a C1 _{to 4} straight chain or branched alkyl group; the carbon number of the fatty aldehyde is 1 to 4; in formula (Y), each _R1 is independently selected from H or methyl, and each _R1 ' is independently selected from H or methyl. 5. The method according to claim 3, characterized in that the fatty aldehyde is formaldehyde or acetaldehyde; and the compound represented by formula (Y) is selected from one or more of p-phenylenediamine, 2-methyl-p-phenylenediamine, tetramethyl-p-phenylenediamine, N,N-dimethyl-1,4-phenylenediamine, N-ethyl-p-phenylenediamine, N,N-diethyl-p-phenylenediamine and N,N-diethyl-3-methyl-p-phenylenediamine. 6. The method according to claim 3, characterized in that the molar ratio between the compound represented by formula (X), the fatty aldehyde and the compound represented by formula (Y) is 1:0.1-3.5:0.3-3. 7. The method according to claim 3, characterized in that the temperature at which the compound represented by formula (X), the fatty aldehyde and the compound represented by formula (Y) react is 50°C to 200°C. 8. The method according to claim 3, characterized in that a solvent is added during the reaction of the compound represented by formula (X), the fatty aldehyde and the compound represented by formula (Y), and the solvent is selected from hydrocarbons with a boiling point between 100°C and 160°C. 9. The method according to claim 3, characterized in that a diluent is added during the reaction of the compound represented by formula (X), the fatty aldehyde and the compound represented by formula (Y), and the diluent is one or more of mineral lubricating oil, polyolefin and polyether. 10. Use of the Mannich base according to claim 1 or 2 or the Mannich base prepared by the method according to any one of claims 3 to 9 as a gasoline detergent.