JP2965679B2 - Method for producing N, N, N ', N'-tetrakis (p-dialkylaminophenyl) -p-benzoquinonebis (immonium perchlorate) - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to N, N, N ', N'-tetrakis (p-dialkylaminophenyl) -p-benzoquinone bis (immonium perchlorine) useful as an infrared absorber. (Acid salt) by electrolytic oxidation.

(Prior art) N, N, N ', N'-tetrakis (p-dialkylaminophenyl) -p-phenylenediamine is represented by the following general formula (I) (wherein R represents an alkyl group). The aminium salt or diimonium salt of this compound is useful as an infrared absorber, and a silver salt of a suitable acid such as silver hexafluoroantimonate or silver perchlorate is represented by the general formula (I). It is produced by a chemical oxidation method of reacting with an amine (JP-B-43-25335, JP-B-45-13326). However, those produced by this method have a problem that a small amount of metallic silver may be mixed into the target product, which causes a deterioration in quality as an infrared absorber, and further uses an expensive silver salt. Therefore, there is a problem that the manufacturing cost increases.

A method for producing by electrolytic oxidation has also been proposed, and Japanese Patent Publication No. 46-5810 discloses a solution comprising N, N, N ', N'-tetraphenyl-p-phenylenediamine, sodium hexafluoroantimonate and acetone. Into the anolyte,
A solution consisting of sodium hexafluoroantimonate and acetone is used as a catholyte and electrolytically oxidized in an electrolytic cell having a diaphragm to give N, N, N ', N'-tetraphenyl-p-benzoquinone bis (immonium hexanoate). A method for obtaining (fluoroantimonates) is disclosed. However, this method has a drawback in that, since an alkali metal salt of an inorganic acid is used, these metallic substances adhere to the cathode, thereby increasing the resistance value and reducing the production efficiency. In addition, since a diaphragm electrolytic cell is used, there is a problem that a complicated apparatus must be used as compared with a non-diaphragm type.

In order to solve the above-mentioned drawback, a method using an inorganic acid such as hexafluoroantimonic acid and perchloric acid or an ammonium salt thereof in place of an alkali metal salt of an inorganic acid (JP-A-61-69991, JP-A-61-69991) No. 61-246391) or a method for preventing the attachment of metal-like substances to the cathode by a method in which a proton source such as water or alcohol coexists in the reaction solution (JP-A-63-290288). Have been. Although these methods are useful, they are aimed at producing an aluminum salt of the compound represented by the general formula (I), and there is no description about the diimonium salt which is the object of the present invention.

(Problems to be Solved by the Invention) The present invention has been made in order to solve the above-mentioned conventional problems, and is directed to N, N, N ', N'-tetrakis (p-dialkylaminophenyl) -p-. An object of the present invention is to provide a method for efficiently producing benzoquinone bis (immonium perchlorate) by an electrolytic oxidation method using a diaphragm-free electrolytic cell.

(Means for Solving the Problems) As a result of repeated studies to solve the above problems, the present inventors have completed the present invention.

That is, the present invention provides a compound represented by the general formula (I) (Wherein R represents an alkyl group), wherein an amine represented by the general formula (II) is electrolytically oxidized in a diaphragm-free electrolytic layer in the presence of perchloric acid or a salt thereof. (Wherein, R represents an alkyl group).
N ', N'-tetrakis (p-dialkylaminophenyl) -p-benzoquinonebis (immonium perchlorate)
It is a manufacturing method of.

The amine represented by the general formula (I) used as a raw material in the present invention is produced by a method described in, for example, Japanese Patent Publication No. 45-13326. That is, p-phenylenediamine and p-nitrochlorobenzene are reacted in the presence of potassium carbonate to obtain N, N, N ', N'-tetrakis (p-nitrophenyl) -p-phenylenediamine. This is hydrogenated using palladium / carbon as a catalyst to produce N, N, N ', N'-tetrakis (p-aminophenyl) -p-phenylenediamine. Furthermore,
When this is reacted with n-alkyl iodide in the presence of potassium carbonate, an amine represented by the general formula (I) is obtained.

As R in the general formulas (I) and (II), a linear or branched alkyl group such as methyl, ethyl, propyl, butyl, hexyl and octyl can be exemplified.

Examples of perchloric acid or a salt thereof used in the present invention include sodium perchlorate, potassium perchlorate, lithium perchlorate and the like, and the amount of perchloric acid or salt thereof is based on the amount of the amine of the general formula (I). 2 to 10 moles.

The object of the present invention, N, N, N ', N'-tetrakis (p
-Dialkylaminophenyl) -p-benzoquinone bis (immonium perchlorate) is obtained by dissolving or suspending the amine of the above general formula (I) and perchloric acid or a salt thereof in a solvent, for example, a non-diaphragm such as a beaker. In the tank, or
In the case of a filter press type electrolytic cell having a plurality of electrode chambers, it can be obtained by energizing while circulating a solution or suspension in each electrode chamber and performing electrolytic oxidation.

The solvent used at the time of electrolytic oxidation is an organic solvent capable of dissolving the amine of the general formula (I) as a raw material or bis (immonium perchlorate) of the general formula (II) as a raw material and allowing the compound to stably exist. Any examples are possible, for example, ethyl acetate, methyl acetate, acetonitrile, chloroform, dichloromethane, methanol, acetone, and the like. These can be used alone or in combination. In addition, a small amount of water can be added to the organic solvent for the purpose of suppressing the formation of deposits on the electrode during electrolysis and reducing the liquid resistance. The amount of the organic solvent used is 2 to 100 times by weight relative to the amine as a raw material, and when water is added, the weight ratio is 0.005 to 0.005 to the organic solvent.
It is 0.1 times.

Electrodes (cathode and anode) used for electrolytic oxidation of the present invention
May be any commonly used one, and examples thereof include platinum, platinum-plated titanium, titanium, and a carbon electrode.

In the electrolytic oxidation of the present invention, the amount of electricity
From around 50%, the cell voltage gradually increases in the constant current electrolysis, and the current density gradually decreases in the constant voltage electrolysis.

The electrolysis conditions of the present invention are the distance between electrodes, stirring or circulation speed,
It depends on the liquid concentration etc. and cannot be determined unconditionally,
For example, when the distance between the electrodes is 1 cm, the cell voltage is preferably 1 to 3 V. At this time, the current density is usually 0.1 to 2 V.
A / dm ² . When the distance between the electrodes is 1 cm, even if the voltage range is exceeded, if the concentration of the raw material amine is as low as about 4% by weight (typically about 1 to 2%) or less, the object of the present invention is not considered. Certain bisimmonium salts are produced, but when the concentration is higher than that, even if the current is passed over the theoretical amount of electricity (2 F / mol), only the aminium salt of the amine of the general formula (I) is produced,
The bisimmonium salt which is the object of the present invention cannot be obtained.
However, since it is extremely important industrially to increase the yield per batch, it is preferable to perform the electrolysis by controlling the cell voltage within the above-mentioned voltage range and making the concentration of the raw material amine as high as possible. When the distance between the electrodes is set to 1 cm, if the voltage falls below the voltage range, the electrolysis takes a long time, which is not preferable.

Therefore, in the constant voltage electrolysis method, the voltage is set within the cell voltage range specified according to the distance between the electrodes, and also in the constant current electrolysis method, the voltage is set within the cell voltage range specified according to the distance between the electrodes. It is preferable to set the current density so as to enter the cell, and to control the cell voltage while appropriately changing (usually lowering) the current density so as to maintain the cell voltage range, thereby performing electrolysis.

The electrolysis temperature is usually 0 to 40 ° C, preferably 20 to 40 ° C.
It is about 30 ° C. Usually, when the electrolysis temperature is about 50 to 60 ° C., it is difficult to obtain the target product.
After passing 50% to 50% of the current at a temperature of 50 to 60 ° C, the desired product can be obtained by an electrolytic oxidation method in which 70 to 145% of the theoretical current is further passed at a temperature of 20 to 30 ° C. Such an energization method is
Even when the concentration of the raw material amine is high, the electrolytic reaction can be carried out in a solution state, and particularly, troubles due to clogging in the electrolytic cell when using a filter press type electrolytic cell considered to be suitable for industrial production Advantageously, it can be prevented.

(Examples) Hereinafter, the present invention will be described in more detail with reference to Examples.
The present invention is not limited to these examples.

Example 1 5.52 g of N, N, N ', N'-tetrakis (p-di-n-butylaminophenyl) -p-phenylenediamine (hereinafter abbreviated as TPPD) was placed in a non-diaphragm electrolytic cell having a capacity of 100 ml. Mmol), 5.06 g (36 mmol) of sodium perchlorate monohydrate, 50 g of ethyl acetate, 25 g of acetonitrile and 1 g of water to obtain a suspension. Two platinum-coated titanium electrodes (manufactured by Nippon Carlit Co., Ltd., trade name: Exelode A, 1.5 cm × 2.8 cm) were inserted into the suspension to make the distance between the electrodes 1 cm, and the mixture was initially stirred at room temperature. The voltage was set to 2.1V. The current density at this time was 1.5 A / dm ² . Proceeds with cell voltage of the electrolytic gradually rises, when it becomes 2.8V, the re cell voltage is re-set the current density to be 2.1V (at application end, decreased to 0.3 A / dm ² Let it happen). This operation was repeated to energize 1388 clones (120% of the theoretical energization amount).

After the completion of the energization, the reaction solution was washed with water, concentrated, n-hexane was added, and the precipitated crystals were separated by filtration and dried, and N, N, N ', N'-tetrakis (p-di-n-butylaminophenyl) was added. -P-
5.2 g of benzoquinone bis (immonium perchlorate) (yield
77%).

Its λmax measured in acetone was 1075 nm.

Example 2 A suspension obtained in the same manner as in Example 1 was heated to 60 ° C. to dissolve the contents. The electrodes used and the distance between the electrodes were the same as in Example 1, the cell voltage was maintained at 2.0 to 2.3 V, and 200 Coulomb was supplied (17% of the theoretical current supply). Then, it was cooled to room temperature and further supplied with 1188 coulombs (103% of the theoretical amount of electricity). Meanwhile, the current density was changed from 1.5 to 0.3 A / dm ² . After energization, the reaction solution was poured into water, and the precipitated crystals were separated by filtration and dried. N, N, N ', N'-tetrakis (p-di-n
-Butylaminophenyl) -p-benzoquinone bis (immonium perchlorate) (6.2 g, yield 92%) was obtained. Its λmax measured in acetone was 1075 nm.

Example 3 Constant current electrolysis at a current density of 0.6 A / dm ² (cell voltage from 1.6
2.2V) and 1274 coulombs (110% of theoretical current)
Electrolytic oxidation was performed in the same manner as in Example 1 except that electricity was supplied, and N, N, N ', N'-tetrakis (p-di-n-butylaminophenyl) -p-benzoquinonebis (immonium perchlorate) was used. 6.1 g (91% yield) was obtained. Its λmax measured in acetone was 1075 nm.

Comparative Example 1 The cell voltage was maintained at 3.6 to 3.1 V and the current density was 4.5 to 0.49 A /
Electrolytic oxidation was carried out in the same manner as in Example 1 except that dm ² was changed. As a result, the bisimmonium salt which is the object of the present invention was not obtained, and the TPPD aminium salt, namely, N,
N, N ', N'-tetrakis (p-di-n-butylaminophenyl) -p-phenylenediamine ammonium perchlorate was obtained. Λmax measured in acetone
Was 951 nm.

Example 4 Without water addition, instead of sodium perchlorate monohydrate
Electrolytic oxidation was performed in the same manner as in Example 1 except that 6.03 g (36 mmol) of a 60% aqueous solution of perchloric acid was used, the current density was set to a constant current of 0.6 A / dm ² , and the cell voltage was maintained at 2.7 to 2.2 V. Was carried out to obtain 3.9 g (yield 58%) of N, N, N ', N'-tetrakis (p-di-n-butylaminophenyl) -p-benzoquinonebis (immonium perchlorate). Its λmax measured in acetone was 1075 nm.

Example 5 73.4 g (79.6 mmol) of TPPD, sodium perchlorate 1
67.3 g (47.9 mmol) of hydrate, 665 g of ethyl acetate, 333 g of acetonitrile and 13 g of water were charged into a beaker having a capacity of 2 and heated to 55 ° C. to prepare an electrolytic solution.

Both sides of a titanium electrode (trade name: Exerode A, 10 cm × 10 cm, manufactured by Nippon Carlit Co., Ltd.) coated with platinum on both sides are connected to two cathodes (Exerode A) through a 1 cm thick gasket. The previously prepared electrolyte was circulated through each electrode chamber of a filter press type electrolytic cell comprising two chambers, and 3,000 clones at 55 ° C. (20% of the theoretical amount of electricity), and then 18400 clones at room temperature ( (120% of theoretical current). During that time, the cell voltage was maintained at 2.1 to 2.4 V and the current density was
Until 1.8~0.6A / dm ² was varied. After energization is completed, Example 1
And N, N, N ', N'-tetrakis (p-di-
75 g (yield 84%) of n-butylaminophenyl) -p-benzoquinone bis (immonium perchlorate) was obtained.

Its λmax measured in acetone was 1075 nm.

Example 6 4.18 g (6 mmol) of N, N, N ', N'-tetrakis (p-diethylaminophenyl) -p-phenylenediamine, 5.06 g of sodium perchlorate monohydrate were placed in a non-diaphragm electrolytic cell having a capacity of 100 ml. g (36 mmol), 50 g of ethyl acetate, 25 g of acetonitrile and 1 g of water were charged. Two platinum-coated titanium electrodes (manufactured by Nippon Carlit Co., Ltd., trade name: Exelode A, 1.5 cm x 2.8 cm) are inserted, the distance between the electrodes is set to 1 cm, and the cell voltage is set to 2.0 V. Voltage electrolysis was carried out, and 1274 coulombs (110% of the theoretical amount of electricity) were supplied while stirring at room temperature. During this time, the current density is decreased from 1.3A / dm ² to 0.6 A / dm ^2.

After the completion of the current supply, the reaction solution was washed with water, concentrated, n-hexane was added, and the precipitated crystals were separated by filtration and dried, and N, N, N ', N'-tetrakis (p-diethylaminophenyl) -p-benzoquinonebis (Imonium perchlorate) 4.5 g (84% yield)
I got

(Effect of the Invention) According to the method of the present invention, N, N, N ', N'-tetrakis (p-dialkylaminophenyl) -p-benzoquinonebis (immonium perchlorate) can be efficiently produced. .

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-63-290288 (JP, A) JP-A-61-246391 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C25B 1/00-3/66 C07C 211/64 C07C 209/00

Claims (3)

(57) [Claims] 1. The compound of the general formula (I) Wherein R represents an alkyl group, wherein the amine represented by the general formula (II) is electrolytically oxidized in a diaphragm-free electrolytic cell in the presence of perchloric acid or a salt thereof. (Wherein, R represents an alkyl group).
N ', N'-tetrakis (p-dialkylaminophenyl) -p-benzoquinonebis (immonium perchlorate)
Manufacturing method. 2. The method according to claim 1, wherein the electrolytic oxidation is carried out by controlling the cell voltage.
A method for producing dialkylaminophenyl) -p-benzoquinone bis (immonium perchlorate). 3. An electric current is supplied at a temperature of 50 to 60 ° C. at a temperature of 50 to 60 ° C., and then at a temperature of 20 to 30 ° C., a further 7 to 14% of the theoretical electric power is applied.
2. The method according to claim 1, wherein the electrolytic oxidation is carried out by supplying a current of 5%.
Or the process for producing N, N, N ', N'-tetrakis (p-dialkylaminophenyl) -p-benzoquinonebis (immonium perchlorate) according to 2 above.