A quaternary ammonium salt compound with a tripyridylbenzene skeleton and its preparation method

Abstract

This invention discloses a quaternary ammonium salt compound with tripyridylbenzene as its backbone and its preparation method, belonging to the technical field of quaternary ammonium salt compounds. Using tripyridylbenzene as a reaction substrate, a nucleophilic substitution reaction occurs with a halogen-substituted alkyl compound or alkoxy compound to generate a quaternary ammonium salt compound. The obtained quaternary ammonium salt compound exhibits excellent surface activity and can be used as a brightener for cyanide-free gold plating, showing broad application prospects in the fields of surfactants and electroplating additives.

Description

Technical Field

[0001] This invention belongs to the field of quaternary ammonium salt compound technology, and relates to a quaternary ammonium salt compound with tripyridylbenzene as the skeleton and its preparation method, as well as the use of the quaternary ammonium salt compound as a surfactant and an additive for electroplating solution. Background Technology

[0002] Surfactants are substances that can significantly reduce the surface tension of liquids and are widely used in detergents, emulsifiers, dispersants, wetting agents, foaming agents, and other fields. Quaternary ammonium salt surfactants, due to their excellent surface activity, good biodegradability, and low toxicity, are widely used in personal care products, household cleaning products, textile printing and dyeing, and oilfield chemicals.

[0003] Most existing quaternary ammonium salt surfactants are traditional alkyl quaternary ammonium salts, with simple structures and relatively limited applications. In recent years, to meet market demand for functional surfactants, researchers have continuously developed quaternary ammonium salts with novel structures, such as introducing polyether segments and aromatic ring groups, in order to obtain better performance, such as stronger emulsifying ability and higher antistatic properties. However, existing novel quaternary ammonium salts still have some shortcomings, such as high synthesis costs, complex production processes, and limited performance improvement. Small molecule quaternary ammonium salts are usually composed of well-defined chemical structures, possessing a single molecular composition and structure. This makes them easier to identify and determine during chemical analysis and characterization. Due to their well-defined structures, the physicochemical properties of small molecule quaternary ammonium salts (such as molecular weight, melting point, boiling point, solubility, etc.) are usually known and predictable. This makes it easier to control and adjust their performance when designing and optimizing products.

[0004] Electroplating is a technique that uses the principle of electrolysis to deposit a thin film of metal or alloy on the surface of metal or other materials. It is widely used to improve the surface hardness, wear resistance, corrosion resistance, and conductivity of materials. Electroplating additives are an important component of electroplating solutions, which can improve the dispersibility of the electroplating solution and enhance the quality and performance of the electroplated layer.

[0005] Commonly used electroplating additives include leveling agents, brighteners, and wetting agents. Leveling agents can adjust the electrochemical properties of the electroplating solution, affecting the current density and potential distribution during the electroplating process, thereby optimizing the growth process of the electroplated layer. This helps to form a more uniform, dense, and strongly bonded coating. Brighteners can significantly improve the brightness and smoothness of the coating, giving it a mirror-like luster. This is crucial for decorative gold plating applications, enhancing the product's aesthetics and market competitiveness. During gold electroplating, brighteners help achieve uniform deposition of gold atoms, ensuring a uniform crystalline structure at the microscopic level. This helps reduce defects in the coating, such as pits, pinholes, and craters. Brighteners improve the adhesion between the coating and the substrate, making the coating adhere more firmly to the substrate surface. This is essential for ensuring the durability and functionality of the coating.

[0006] Quaternary ammonium salts, due to their positively charged nature in the plating bath, can adsorb onto the cathode surface, increasing polarization, and are often used as brighteners for electroplating gold. Electroplating gold brighteners are generally classified into inorganic and organic brighteners. Inorganic brighteners typically include metallic or semi-metallic elements such as copper, nickel, cobalt, arsenic, thallium, and antimony, and their dosage is generally between 0.1-1 mg / L. These inorganic brighteners can significantly improve the grain size and brightness of the plating layer, and have a significant impact on the color, pinhole rate, hardness, stress, and wear resistance of the plating layer. However, the addition of inorganic brighteners usually increases the stress of the gold plating layer and reduces its ductility. Furthermore, some inorganic brighteners, such as arsenic and thallium, are highly toxic and may pose health risks during use. Organic brighteners are typically small-molecule compounds containing sulfur or nitrogen, and their dosage is generally between 0.1-10 g / L. For example, US Patent 6565732B1 states that heterocyclic compounds, such as bipyridine, phenanthrene, thiophenecarboxylic acid, and pyridine, are effective brighteners for gold plating solutions, used in amounts ranging from 0.1 to 10 g / L. German Patent DE 2355581 also mentions that pyridine-3-sulfonic acid is a typical organic brightener that can shift or extend the current density range for depositing bright gold layers towards higher current densities, used in amounts ranging from 1 to 10 g / L. However, excessive addition of organic brighteners can lead to additive trapping, increasing the brittleness of the plating layer. Therefore, it is necessary to develop new organic brighteners that avoid the use of certain highly toxic inorganic additives while minimizing additive trapping. Summary of the Invention

[0007] The purpose of this invention is to provide a quaternary ammonium salt compound with tripyridylbenzene as the backbone and its preparation method. Using tripyridylbenzene as the reaction substrate, it undergoes a nucleophilic substitution reaction with halogen-substituted alkyl or alkoxy compounds to generate the quaternary ammonium salt compound, which is suitable for use in surfactants and electroplating additives. This invention achieves its purpose through the following specific technical solutions.

[0008] A primary aspect of this invention is to provide a quaternary ammonium salt compound with a tripyridylbenzene backbone, the structure of which is shown in the following formula:

[0009] ,

[0010] In the formula, A is an alkylene group with 1-6 carbon atoms, such as methylene, ethylene, propanediyl, butylene, pentanediyl, or hexanediyl; or a cycloalkylene group with 3-6 carbon atoms, such as cyclopropane 1,2-diyl, cyclobutane 1,3-diyl, cyclopentane 1,4-diyl, cyclohexane 1,5-diyl, or phenylenediyl; or a group in which hydrogen atoms of the aforementioned alkylene or cycloalkylene groups are substituted, such as hydroxymethylene, 2-hydroxyethylene, or 1-methylcyclopropane-2,3-diyl; or a repeating unit with the structure -OCH2-CH2-, wherein the number of repeating units is 1-4. Preferably, A is methylene, ethylene, phenylenemethylene, or -OCH2-CH2-; X is Cl, Br, or I, preferably Cl or Br, and most preferably Cl.

[0011] Preferably, the structure of the compound is one of the following formulas:

[0012] ,

[0013] ,

[0014] ,

[0015] ,

[0016] ,

[0017] .

[0018] Another aspect of the present invention is to provide a method for preparing the aforementioned compound, comprising the following steps:

[0019] S1 Dissolve 1,3,5-tris(4-pyridyl)benzene in an organic solvent to obtain a 1,3,5-tris(4-pyridyl)benzene solution;

[0020] S2. A compound containing both halogen and hydroxyl groups is added to a solution of 1,3,5-tris(4-pyridyl)benzene, and the mixture is heated to react.

[0021] After the S3 reaction is complete, the solution is cooled and purified by column chromatography to obtain the compound product.

[0022] Furthermore, the organic solvent mentioned in step S1 is one or more of ethylene glycol, propylene glycol, glycerol, and ethylene glycol monomethyl ether.

[0023] Furthermore, the compound containing both halogen and hydroxyl groups in step S2 is 3-chloro-1-propanol, 2-chloroethoxyethanol, 3-chloro-1,2-propanediol, 3-chloro-1-phenyl-1-propanol, or triethylene glycol monochlorool.

[0024] Furthermore, in step S2, the reaction temperature is 160~180℃ and the reaction time is 0.5~2h.

[0025] Furthermore, in step S2, the molar ratio of the compound containing both halogen and hydroxyl groups to 1,3,5-tris(4-pyridyl)benzene is (2.9~3.1):1.

[0026] Another aspect of the present invention is to provide the use of the aforementioned compound as a surfactant.

[0027] Another aspect of the present invention is to provide the use of the aforementioned compound as an additive in an electroplating solution.

[0028] Furthermore, the electroplating solution comprises: 20-50 g / L of sulfite, 10-15 g / L of sodium gold sulfite (based on gold element), 10-20 g / L of sulfate, 10-20 g / L of phosphate, 10-30 g / L of pyrophosphate, 10-30 g / L of tartrate, and 0.1-1.0 mg / L of the aforementioned compound as a brightener for gold plating.

[0029] Compared with the prior art, the present invention has the following advantages and beneficial effects: the compound of the present invention, as a brightener for electroplating gold, produces a fast electroplating speed and a bright and uniform coating. The addition amount is between 0.1-1 mg / L, which can avoid the use of some highly toxic inorganic additives and at the same time, it is not easy to cause additive inclusion. Detailed Implementation

[0030] The technical solution of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention. Example 1

[0031] A quaternary ammonium salt compound with the following chemical structural formula:

[0032]

[0033] The synthesis method is as follows:

[0034] In a two-necked flask equipped with a magnetic stirrup and a condenser, 20 mL of ethylene glycol was added and the temperature was raised to 80 °C. Next, 3.2 mmol of 1,3,5-tris(4-pyridyl)benzene was added to the flask, ensuring complete dissolution in the ethylene glycol. After complete dissolution, 9.6 mmol of 3-chloro-1-propanol was added, and the temperature was adjusted to 170 °C. The reaction was maintained at 170 °C for 1 hour. After the reaction was complete, the solution in the flask was cooled to room temperature and then purified by column chromatography to obtain the purified target compound.

[0035] Nuclear magnetic resonance (NMR) spectroscopy (500 MHz, DMSO- d 6 (22℃):

[0036] 9.08(6H,ArH), 8.96(6H,ArH), 8.04(3H,ArH), 5.01(6H,CH2), 4.33(3H,OH), 3.49(6H,CH2), 2.22(6H,CH2). Example 2

[0037] A quaternary ammonium salt compound with the following chemical structural formula:

[0038]

[0039] The synthesis method is as follows:

[0040] In a two-necked flask equipped with a magnetic stirrup and a condenser, 20 mL of ethylene glycol was added and the temperature was raised to 80 °C. Next, 3.2 mmol of 1,3,5-tris(4-pyridyl)benzene was added to the flask, ensuring complete dissolution in the ethylene glycol. After complete dissolution, 9.6 mmol of 2-chloroethoxyethanol was added, and the temperature was adjusted to 170 °C. The reaction was maintained at 170 °C for 1 hour. After the reaction was complete, the solution in the flask was cooled to room temperature and then purified by column chromatography to obtain the purified target compound.

[0041] Nuclear magnetic resonance (NMR) spectroscopy (500 MHz, DMSO- d 6 (22℃):

[0042] 9.09(6H,ArH), 8.98(6H,ArH), 8.07(3H,ArH), 5.02(3H,OH), 4.36(6H,CH2), 4.11(6H,CH2), 3.70(6H,CH2), 3.54(6H,CH2). Example 3

[0043] A quaternary ammonium salt compound with the following chemical structural formula:

[0044]

[0045] The synthesis method is as follows:

[0046] In a two-necked flask equipped with a magnetic stirrup and a condenser, 20 mL of ethylene glycol was added and the temperature was raised to 80 °C. Next, 3.2 mmol of 1,3,5-tris(4-pyridyl)benzene was added to the flask, ensuring complete dissolution in the ethylene glycol. After complete dissolution, 9.6 mmol of 3-chloro-1,2-propanediol was added, and the temperature was adjusted to 170 °C. The reaction was maintained at 170 °C for 1 hour. After the reaction was complete, the solution in the flask was cooled to room temperature and then purified by column chromatography to obtain the purified target compound.

[0047] Nuclear magnetic resonance (NMR) spectroscopy (500 MHz, DMSO- d 6 (22℃):

[0048] 9.08(6H,ArH), 8.96(6H,ArH), 8.04(3H,ArH), 5.37(3H,OH), 5.29(6H,CH2), 4.01(3H, OH), 3.60(3H,CH), 3.59(6H,CH2). Example 4

[0049] A quaternary ammonium salt compound with the following chemical structural formula:

[0050]

[0051] The synthesis method is as follows:

[0052] In a two-necked flask equipped with a magnetic stirrup and a condenser, 20 mL of ethylene glycol was added and the temperature was raised to 80 °C. Next, 3.2 mmol of 1,3,5-tris(4-pyridyl)benzene was added to the flask, ensuring complete dissolution in the ethylene glycol. After complete dissolution, 9.6 mmol of 3-chloro-1-phenyl-1-propanol was added, and the temperature was adjusted to 170 °C. The reaction was maintained at 170 °C for 1 hour. After the reaction was complete, the solution in the flask was cooled to room temperature and then purified by column chromatography to obtain the purified target compound.

[0053] Nuclear magnetic resonance (NMR) spectroscopy (500 MHz, DMSO- d 6 (22℃):

[0054] 9.13(6H,ArH), 9.02(6H,ArH), 8.11(3H,ArH), 7.32(6H,ArH), 7.25(9H,ArH), 5.01(6H,CH2), 4.71(3H, OH), 4.41(3H,CH), 2.51(6H,CH2). Example 5

[0055] A quaternary ammonium salt compound with the following chemical structural formula:

[0056]

[0057] The synthesis method is as follows:

[0058] In a two-necked flask equipped with a magnetic stirrup and a condenser, 20 mL of ethylene glycol was added and the temperature was raised to 80 °C. Next, 3.2 mmol of 1,3,5-tris(4-pyridyl)benzene was added to the flask, ensuring complete dissolution in the ethylene glycol. After complete dissolution, 9.6 mmol of triethylene glycol monochloroethanol was added, and the temperature was adjusted to 170 °C. The reaction was maintained at 170 °C for 1 hour. After the reaction was complete, the solution in the flask was cooled to room temperature and then purified by column chromatography to obtain the purified target compound.

[0059] Nuclear magnetic resonance (NMR) spectroscopy (500 MHz, DMSO- d 6 (22℃):

[0060] 9.11(6H,ArH), 8.99(6H,ArH), 8.06(3H,ArH), 4.33(6H,CH2), 4.21(6H,CH2),3.75(3H, OH), 3.67(6H,CH2), 3.58(6H,CH2), 3.52(6H,CH2), 3.50(6H,CH2). Example 6

[0061] A quaternary ammonium salt compound with the following chemical structural formula:

[0062]

[0063] The synthesis method is as follows:

[0064] In a two-necked flask equipped with a magnetic stirrup and a condenser, 20 mL of ethylene glycol was added and the temperature was raised to 80 °C. Next, 3.2 mmol of 1,3,5-tris(4-pyridyl)benzene was added to the flask, ensuring complete dissolution in the ethylene glycol. After complete dissolution, 9.6 mmol of triethylene glycol monochloroethanol was added, and the temperature was adjusted to 160 °C. The reaction was maintained at 170 °C for 1 hour. After the reaction was complete, the solution in the flask was cooled to room temperature and then purified by column chromatography to obtain the purified target compound. Example 7

[0065] A quaternary ammonium salt compound with the following chemical structural formula:

[0066]

[0067] The synthesis method is as follows:

[0068] In a two-necked flask equipped with a magnetic stirrup and a condenser, 20 mL of ethylene glycol was added and the temperature was raised to 80 °C. Next, 3.2 mmol of 1,3,5-tris(4-pyridyl)benzene was added to the flask, ensuring complete dissolution in the ethylene glycol. After complete dissolution, 9.6 mmol of triethylene glycol monochloroethanol was added, and the temperature was adjusted to 180 °C. The reaction was maintained at 170 °C for 1 hour. After the reaction was complete, the solution in the flask was cooled to room temperature and then purified by column chromatography to obtain the purified target compound. Example 8

[0069] A quaternary ammonium salt compound with the following chemical structural formula:

[0070]

[0071] The synthesis method is as follows:

[0072] In a two-necked flask equipped with a magnetic stirrup and a condenser, 20 mL of ethylene glycol was added and the temperature was raised to 80 °C. Next, 3.2 mmol of 1,3,5-tris(4-pyridyl)benzene was added to the flask, ensuring complete dissolution in the ethylene glycol. After complete dissolution, 9.6 mmol of triethylene glycol monochloroethanol was added, and the temperature was adjusted to 170 °C. The reaction was maintained at 170 °C for 0.5 hours. After the reaction was complete, the solution in the flask was cooled to room temperature and then purified by column chromatography to obtain the purified target compound. Example 9

[0073] A quaternary ammonium salt compound with the following chemical structural formula:

[0074]

[0075] The synthesis method is as follows:

[0076] In a two-necked flask equipped with a magnetic stirrup and a condenser, 20 mL of ethylene glycol was added and the temperature was raised to 80 °C. Next, 3.2 mmol of 1,3,5-tris(4-pyridyl)benzene was added to the flask, ensuring complete dissolution in the ethylene glycol. After complete dissolution, 9.6 mmol of triethylene glycol monochloroethanol was added, and the temperature was adjusted to 170 °C. The reaction was maintained at 170 °C for 2 hours. After the reaction was complete, the solution in the flask was cooled to room temperature and then purified by column chromatography to obtain the purified target compound. Example 10

[0077] The surface tension of the quaternary ammonium salt compound synthesized in Example 2 was tested, and the detection process and results are as follows:

[0078] Different concentrations of quaternary ammonium salt polymer solutions were prepared using ultrapure water, and surface tension was measured at 25°C using the ring-drop method. The critical micelle concentration (CMC) of the cationic surfactant prepared in Example 2 was 8.4 × 10⁻⁶. - 4 mol / L, compared with the commonly used surfactant sodium dodecyl sulfonate (CMC=9.0×10⁻⁶). -3 With a surface activity comparable to that of mol / L, the lowest surface tension reached 35.71 mN / m, indicating that it has excellent surface activity. Example 11

[0079] The quaternary ammonium salt polymer synthesized in Example 2 was used as a brightener for cyanide-free gold plating and combined with a gold plating complexing agent as a test example of cyanide-free gold plating. First, a cyanide-free gold plating solution containing the quaternary ammonium salt polymer of Example 1 as a brightener was prepared. The composition of the plating solution was as follows: sodium sulfite (40 g / L), sodium sulfate (15 g / L), sodium dihydrogen phosphate (15 g / L), potassium sodium tartrate (20 g / L), potassium pyrophosphate (20 g / L), sodium gold sulfite (12 g / L, measured as gold), and the brightener being the polymer from Example 1 (0.6 ppm). Then, a plating solution with a surface area of ​​0.08 dm² was prepared. 2 The brass sheet was placed in the aforementioned cyanide-free gold plating solution, and the plating was performed at a temperature of 55°C, a pH of 8.5, and a current density of 0.4 A / dm³. 2 Electroplating was performed for 3.5 hours under specific conditions, resulting in a mirror-like finish on the surface of the plated sheet. Comparative Example 1

[0080] First, prepare a cyanide-free gold plating solution without brighteners. The solution composition is as follows: sodium sulfite (40 g / L), sodium sulfate (15 g / L), sodium dihydrogen phosphate (15 g / L), potassium sodium tartrate (20 g / L), potassium pyrophosphate (20 g / L), and sodium gold sulfite (12 g / L, measured as gold). Then, a plating solution with a surface area of ​​0.08 dm² is prepared. 2 The brass sheet was placed in the aforementioned cyanide-free gold plating solution, and the plating was performed at a temperature of 55°C, a pH of 8.5, and a current density of 0.4 A / dm³. 2 Electroplating was performed for 3.5 hours under specific conditions, resulting in a matte-finished sheet.

[0081] Although embodiments of the present invention have been shown and described above, it is understood that these embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and alterations to the above embodiments within the scope of the present invention without departing from its principles and spirit. The scope of protection of the present invention is defined by the claims and their equivalents.

Claims

1. A quaternary ammonium salt compound with a tripyridylbenzene backbone, characterized in that, Its structure is shown in the following formula: 。 2. The method for preparing the compound according to claim 1, characterized in that, Includes the following steps: S1 Dissolve 1,3,5-tris(4-pyridyl)benzene in an organic solvent to obtain a 1,3,5-tris(4-pyridyl)benzene solution; S2 Add 2-chloroethoxyethanol to a solution of 1,3,5-tris(4-pyridyl)benzene and heat to react; After the S3 reaction is complete, the solution is cooled and purified by column chromatography to obtain the compound product.

3. The preparation method according to claim 2, characterized in that, The organic solvent mentioned in step S1 is one or more of ethylene glycol, propylene glycol, glycerol, and ethylene glycol monomethyl ether.

4. The preparation method according to claim 2, characterized in that, In step S2, the reaction temperature is 160~180℃ and the reaction time is 0.5~2h.

5. The preparation method according to claim 3, characterized in that, In step S2, the molar ratio of 2-chloroethoxyethanol to 1,3,5-tris(4-pyridyl)benzene is (2.9~3.1):

1.

6. Use of the compound according to claim 1 as a surfactant.

7. Use of the compound according to claim 1 as an additive in electroplating solutions.

8. The use according to claim 7, characterized in that, The electroplating solution comprises the following components: 20-50 g / L of sulfite, 10-15 g / L of sodium gold sulfite (based on gold element), 10-20 g / L of sulfate, 10-20 g / L of phosphate, 10-30 g / L of pyrophosphate, 10-30 g / L of tartrate, and 0.1-1.0 mg / L of the compound described in claim 1.

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