JP2662654B2 - Method for producing N, N-disubstituted anilines - Google Patents

Description

The present invention relates to a method for producing N, N-disubstituted anilines,
More specifically, the present invention relates to a method for producing an N, N-disubstituted aniline which is an intermediate of N, N-disubstituted p-phenylenediamine which is useful as a main agent of a color developer or a raw material for synthesis of an azo dye.

[Prior Art] N, N-disubstituted p-phenylenediamine useful as a raw material for various industrial chemicals such as a main agent of a color developer is synthesized from N, N-disubstituted aniline known as an intermediate thereof. .

Conventionally, as a method for synthesizing N, N-disubstituted aniline,
A method in which an N-substituted aniline is reacted with an alkyl bromide for a long time (JP-A-47-11534 and JP-A-50-13152).
6), a method of reacting a p-toluenesulfonic acid ester of a monoalkyl ether with an N-substituted aniline (see JP-A-51-95849), and a method of reacting an N-substituted aniline with an anhydrous phosphate. To react an N-substituted aniline with an alkyl chloride (JP-B-60-1302)
No. 3) is known.

[Problems to be Solved by the Invention] However, all of these synthesis methods use an N-substituted aniline as a starting material. It is known that a mixture of aniline and N, N-disubstituted aniline can be obtained by separation and purification using a method such as vacuum distillation. Since a large amount of N, N-disubstituted aniline to which two groups are bonded is by-produced, there is a disadvantage that the yield of N-substituted aniline to which one substituent is bonded is low, which is industrially disadvantageous. It was a synthesis method and the price was high.

[Means for Solving the Problems] The present invention provides a method for producing a specific N, N-disubstituted aniline by passing through an N-substituted aniline obtained by reacting an alkylene oxide with an aniline. It was found.

That is, according to the present invention, general formula I (However, R in the formula represents H, Cl, NO ₂ or an alkyl group having 1 to 6 carbon atoms, an alkyloxy group or an alkenyl group, and the bonding position of R is ortho, meta or para with respect to —NH ₂₎ . Anilines represented by the general formula II (Wherein, R ¹ represents H, CH ₃ or CH ₂ Cl, and R ² represents H or CH ₃ ). (Wherein, R in the formula, R ¹ and R ² represent. The same as described above) to produce the N- substituted aniline derivative represented by, after separation of this, the general formula III R ³ -X (where Wherein R ³ represents an alkyl or alkenyl group having 1 to 6 carbon atoms and X represents a halogen.) An organic halide represented by the formula: (Wherein R, R ¹ , R ² and R ³ are the same as described above, and R ⁴ is H or R ³ ). it can.

It should be noted that among the products of the present invention, the general formula V wherein R ^{4 of the} general formula IV is H (However, R in the formula represents H, Cl, NO ₂ or an alkyl group having 1 to 6 carbon atoms, an alkyloxy group or an alkenyl group, and the bonding position of R is ortho, meta or para with respect to —NH ₂₎ . And R ¹ is H, CH ₃ , CH ₂
Represents Cl and R ² represents H or CH ₃ . N represented by), N- general formula disubstituted anilines III R ⁵ -X (provided that, R ⁵ in the formula is an alkyl or alkenyl group having 1 to 6 carbon atoms, X is represented by halogen.) Reacting the resulting organic halide in the presence of a strong alkali to obtain a compound of the general formula VI (Where R in the formula represents the same as above, R ¹ represents H, CH ₃ , CH ₂ Cl, R ² represents H or CH ₃ , R ³
And R ⁵ each independently represent an alkyl or alkenyl group having 1 to 6 carbon atoms. The N, N-disubstituted anilines represented by the following formula can be produced.

[Specific description of the invention] (1) First reaction (addition reaction of alkylene oxide) Anilines General formula I used as a raw material in the present invention. Anilines of, R is H, Cl, NO ₂ or an alkyl group the alkyl group or alkenyl group having 1 to 6 carbon atoms, the bonding position of R is ortho to the -NH _2, meta,
Any of the para position may be used. Specific examples include aniline, toluidine, anisidine, nitroaniline, chloroaniline and the like.

Alkylene oxide Examples of the alkylene oxide represented by the general formula II to be added to the aniline include ethylene oxide,
Propylene oxide, isobutylene oxide, epichlorohydrin and the like can be mentioned, and ethylene oxide and propylene oxide are particularly suitable.

Addition of Alkylene Oxide When adding 1 mol of alkylene oxide to 1 mol of aniline, the reaction molar ratio (aniline / alkylene oxide) is 1.25 to 10, particularly 2
It is preferable to set it to 30 in view of the yield. At this time, as a catalyst, a Lewis acid is used in an amount of 0.05 to aniline.
Addition of 0.20% by weight improves the yield.

When the molar ratio is 10 or more, the yield per batch decreases, which is industrially disadvantageous.

In the case of an alkylene oxide 1 mol adduct, after the completion of the reaction, unreacted anilines are separated and recovered by vacuum distillation or the like to obtain a compound of the general formula (Wherein R represents the same as above, R ¹ represents H, CH ₃ , CH ₂ Cl, and R ² represents H or CH ₃ ). Can be

Specific examples of such N-substituted anilines include N- (β-hydroxyethyl) -aniline N- (β-hydroxypropyl) -aniline N- (β-hydroxyethyl) -toluidine N- (β-hydroxypropyl ) -Toluidine N- (β-hydroxyethyl) -anisidine N- (β-hydroxypropyl) -anisidine N- (β-hydroxyethyl) -nitroaniline N- (β-hydroxypropyl) -nitroaniline N- (β- (Hydroxyethyl) -chloroaniline N- (β-hydroxypropyl) -chloroaniline and the like.

(2) Second reaction (N-alkylation reaction) This N-substituted aniline is N-alkylated by N-alkylation using an organic halide in the presence of a deoxidizing agent.
-Produce disubstituted anilines.

Organic halides organic halide used in the second reaction is a Formula ^{R 3 -X (III), R} 3 is an organic substituent, X is halogen.

Such organic halides include organic bromides,
Organic iodides are conceivable, but since organic bromides and iodides are expensive, it is better to use organic chlorides.
Examples of such an organic chloride include methyl chloride, ethyl chloride, n-propyl chloride, ethylene chlorohydrin, methoxyethyl chloride and the like.

Deoxidizing agent However, since such organic chlorides have low reactivity, the yield can be improved by using a deoxidizing agent.

As the deoxidizing agent used in the present invention, potassium carbonate, sodium carbonate, sodium phosphate, sodium hydrogen phosphate, sodium dihydrogen phosphate, potassium phosphate, potassium hydrogen phosphate, potassium dihydrogen phosphate, calcium phosphate, phosphorus There are calcium hydrogen oxyhydrate, calcium dihydrogen phosphate, potassium hydroxide, sodium hydroxide, and the like. Among them, when a deacidifier having weak alkalinity such as phosphate is used, N-alkylation reaction is performed. When a strong alkali such as potassium hydroxide or sodium hydroxide is used, the hydroxyl group of the formula II is alkylated.

Such a deoxidizing agent is usually used as an aqueous solution, and is used in such an amount that its alkali value becomes equal to or more than that of an organic chloride.

Iodide compound In the present invention, an iodide compound can be added as a catalyst. Such iodide compounds, specifically, NaI, KI and the like inorganic salts and I ₂ iodine such as.

The iodide compound is preferably used in an amount of 0.01 to 0.2 times the theoretical amount of iodine with respect to the N-substituted aniline,
Most preferably, it is 3 to 0.1 times mol. If the amount used is less than 0.01 mole, the reaction time will be prolonged, and if it exceeds 0.2, the cost of the catalyst will be high because the iodide compound is expensive, which is industrially disadvantageous.

Reaction conditions The reaction conditions in the second reaction are as follows:
The temperature is 150 ° C, preferably 30 to 110 ° C.

If the temperature is lower than 0 ° C, the reaction time becomes longer.
If the ratio exceeds the above, side reactions such as hydrolysis occur, and both are not preferred. The reaction pressure is 5 kg / cm ² G or less, preferably 2 to
4 kg / cm ² G. Even if the reaction pressure exceeds 5 kg / cm ² G, there is not much improvement effect by that.

In the second reaction, a solvent may be used, but it is preferable to carry out the reaction without a solvent other than the aqueous solution of the deoxidizing agent as long as there is no problem in the solubility of the raw materials.

In the second reaction, the use of an iodide compound as the deoxidizing agent and the catalyst allows the reaction to proceed quantitatively in a short time, whereby the N, N-
Disubstituted anilines can be produced in high yield and at lower cost.

The N, N-disubstituted anilines thus produced have the general formula Wherein R, R ¹ , R ² and R ³ are the same as above, and R ⁴ is H or R ³ .

Specifically, when a weakly alkaline deoxidizing agent is used, R ^{4 in the} above formula (IV) is H, and such an N, N-disubstituted aniline is, for example, N-methyl-N- ( β-
Hydroxyethyl) -aniline, N-ethyl-N- (β
-Hydroxyethyl) -aniline, N-propyl-N-
(Β-hydroxyethyl) -aniline, N-methyl-N
-(Β-propyl) -aniline, N-ethyl-N- (β
Aniline derivatives such as -hydroxypropyl) -aniline, N-methyl-N- (β-hydroxyethyl) -toluidine, N-propyl-N- (β-hydroxyethyl)-
Toluidine derivatives such as toluidine, N-methyl-N- (β-hydroxypropyl) -toluidine, N-ethyl-N- (β-hydroxypropyl) -toluidine, N-methyl-N- (β-hydroxyethyl) -anisidine N-ethyl-N- (β-hydroxyethyl) -anisidine, N-propyl-N- (β-hydroxyethyl) -anisidine, N-methyl-N- (β-hydroxypropyl) -anisidine, N-ethyl- Anisidine derivatives such as N- (β-hydroxypropyl) -anisidine, N-methyl-N- (β-hydroxyethyl) -nitroaniline, N-ethyl-N- (β-hydroxyethyl)
-Nitroaniline, N-propyl-N- (β-hydroxyethyl) -nitroaniline, N-methyl-N- (β
Nitroaniline derivatives such as -hydroxypropyl) -nitroaniline, N-ethyl-N- (β-hydroxypropyl) -nitroaniline, N-methyl-N- (β-hydroxyethyl) -chloroaniline, N-ethyl-N -(Β-hydroxyethyl)
-Chloroaniline, N-propyl-N- (β-hydroxyethyl) -chloroaniline, N-methyl-N- (β-
(Hydroxypropyl) -chloroaniline, N-ethyl-
And chloroaniline derivatives such as N- (β-hydroxypropyl) -chloroaniline.

The product when a strong alkali is used as the deoxidizing agent is, for example, the above-mentioned N-methyl-N- (β-hydroxyethyl)
N-methyl-N- (β-methoxyethyl) -aniline is obtained instead of -aniline.

(3) Third reaction (alkoxylation reaction) The N, N-disubstituted anilines thus obtained are
When R ⁴ is H in the general formula (IV) (general formula V), an organic halide is further reacted in the presence of a strong alkali to form N, N- having two different substituents.
Disubstituted anilines can be produced.

Organic halide Examples of such an organic halide of the general formula III R ⁵ -X (provided that, R ⁵ is an alkyl or alkenyl group having 1 to 6 carbon atoms in the formula, X is halogen.) Represented by organic Organic bromide and organic iodide are considered as such organic halides. However, since organic bromide and organic iodide are expensive, a method using an organic chloride is preferable. Examples of such organic chlorides include methyl chloride, ethyl chloride, n-propyl chloride, ethylene chlorohydrin, methoxyethyl chloride and the like.

Deoxidizing agent As the deoxidizing agent used at this time, a strong alkaline compound such as a hydroxide of an alkali or an alkaline earth metal is used. Such deoxidizing agents include, for example, potassium hydroxide, sodium hydroxide, calcium hydroxide, barium hydroxide and the like, among which potassium hydroxide and sodium hydroxide are preferable.

The deoxidizing agent can be used as a solid or an aqueous solution.
When used in an aqueous solution, the concentration is preferably 10 to 80% by weight,
Particularly, 30 to 60% by weight is preferable.

Reaction conditions As in the second reaction, the third reaction can be carried out at a reaction temperature of 0 to 150 ° C, preferably 30 to 110 ° C. If the temperature is lower than 0 ° C., the reaction time becomes longer. If the temperature is higher than 150 ° C., side reactions such as hydrolysis occur, which is not preferable. The reaction pressure is 5 kg / cm ² G or less, preferably 2~4kg / cm ² G. Even if the reaction pressure exceeds 5 kg / cm ² G, there is not much improvement effect.

In carrying out the method of the present invention, a solvent may be used, but it is preferable to carry out the reaction without a solvent other than the aqueous solution of the deoxidizing agent unless there is a problem in the solubility of the raw materials.

Such a deoxidizing agent is usually used as an aqueous solution, and is used in an amount equal to or more than the molar amount of an organic chloride at an alkali value thereof, and a catalyst is used as a catalyst in an amount of 0.01 to 0.2 times mol of an iodide compound with respect to N-substituted anilines. By using the compound, the reaction can proceed quantitatively in a short time, whereby the target N, N-disubstituted anilines can be produced in high yield and at lower cost.

General formula produced in this way (However, R, R ¹ , R ² and R ³ in the formula are the same as before, and R ⁵ independently of R ³ represents an alkyl or alkenyl group having 1 to 6 carbon atoms.) Examples of the N-disubstituted anilines include N-ethyl-N- (β-methoxyethyl) -aniline, N-ethyl-N- (β-methoxypropyl) -aniline, N-methyl-N- (β- Aniline derivatives such as ethoxyethyl) -aniline, N-methyl-N- (β-ethoxypropyl) -aniline, N-ethyl-N- (β-methoxyethyl) -toluidine, N-ethyl-N- (β-methoxy Propyl) -toluidine, N-methyl-N- (β-ethoxyethyl) -toluidine, N-methyl-N- (β-ethoxypropyl)
-Toluidine derivatives such as toluidine, N-ethyl-N- (β-methoxyethyl) -anisidine, N-ethyl-N- (β-methoxypropyl) -anisidine, N-methyl-N- (β-ethoxyethyl)- Anisidine, N-methyl-N- (β-ethoxypropyl)
-Anisidine derivatives such as -anisidine, N-ethyl-N- (β-methoxyethyl) -nitroaniline, N-ethyl-N- (β-methoxyethyl) -nitroaniline, N-methyl-N- (β-ethoxyethyl )
Nitroaniline derivatives such as nitroaniline, N-methyl-N- (β-ethoxypropyl) -nitroaniline, N-methyl-N- (β-ethoxyethyl) -chloroaniline, N-ethyl-N- (β -Methoxyethyl) -chloroaniline, N-ethyl-N- (β-methoxypropyl) -chloroaniline, N-methyl-N- (β-ethoxyethyl) -chloroaniline, N-methyl-N- (β-
And chloroaniline derivatives such as ethoxypropyl) -chloroaniline.

[Examples] Next, the present invention will be specifically described with reference to examples.

Example 1 Addition reaction of alkylene oxide m-toluidine 24 was added to a 500 ml autoclave with electromagnetic stirring.
9.1 g (2.33 mol) was charged, and the inside of the vessel was replaced with nitrogen gas. Then, the reaction temperature was raised to 110 ± 5 ° C., and 38.0 g of ethylene oxide (0.
8639 mol). The introduction was completed in 10 minutes, and aging was performed at the same temperature for 30 minutes.

Thereafter, unreacted m-toluidine was recovered by vacuum distillation to obtain 128.2 g (0.849 mol) of N- (β-hydroxyethyl) -m-toluidine (98% yield based on ethylene oxide).

The content of this N- (β-hydroxyethyl) -m-toluidine was analyzed by gas chromatography and found to be 98%.

N-alkylation reaction 72.0 g (0.477 mol) of N- (β-hydroxyethyl) -m-toluidine obtained in the above reaction, 155.0 g (0.284 mol) of a 30% aqueous solution of trisodium phosphate and potassium iodide 2.4 g (0.014 mol) was charged into a 500 ml electromagnetically stirred autoclave, and the inside of the vessel was replaced with nitrogen gas. The reaction conditions were 100 ± 5 ° C., the pressure was 3 ± 1 kg / cm ² G, and ethyl chloride 4 g was added.
0.5 g (0.628 mol) were introduced. The introduction was completed in 4 hours, and aging was performed for 6 hours at the same temperature. After aging, by-product NaCl was removed by washing with water, and N-ethyl-N- (β
82.6 g (0.461 mol) of -hydroxyethyl-m-toluidine were obtained (97% yield).

This N-ethyl-N- (β-hydroxyethyl-m-
The content of toluidine was analyzed by gas chromatography and found to be 96%.

Examples 2 to 6 In the same manner as in Example 1, the compounds shown in the following table were synthesized. The results are shown in Table 1.

Example 7 Addition reaction of alkylene oxide m-toluidine 24 was added to a 500 ml autoclave with electromagnetic stirring.
After 9.1 g (2.33 mol) was added and the atmosphere was replaced with nitrogen, the reaction temperature was raised to 110 ± 5 ° C., and ethylene oxide (0.863
Mol) was introduced. The introduction was completed in 10 minutes, and aging was performed at the same temperature for 30 minutes.

Thereafter, unreacted m-toluidine was recovered by vacuum distillation, and N- (β-hydroxyethyl) -m-toluidine was recovered.
128.2 g (0.849 mol) were obtained (yield 98% / EO).

The content of this N- (β-hydroxyethyl) -m-toluidine was analyzed by gas chromatography and found to be 98%.

N-alkylation reaction 72.0 g (0.477 mol) of N- (β-hydroxyethyl) -m-toluidine produced by the above reaction and 114.5 g (1.43 mol) of a 50% aqueous sodium hydroxide solution were subjected to electromagnetic stirring.
After charging into a 500 ml autoclave and purging with nitrogen, the reaction conditions were adjusted to 60 ± 5 ° C. and 3 ± 1 kg / cm ² G, and 53.0 g (1.05 mol) of methyl chloride was introduced. The introduction was completed in 3 hours. Thereafter, aging was performed at the same temperature for 9 hours.

After aging, the by-produced sodium chloride was removed by washing with water to obtain 82.4 g (0.460 mol) of N-methyl-N- (β-methoxyethyl) m-toluidine (98% yield).

The content of this N-methyl-N- (β-methoxyethyl) m-toluidine was analyzed by gas chromatography and found to be 98%.

Examples 8 to 12 In the same manner as in Example 7, the compounds shown in Table 2 were synthesized. The results are shown in Table 2.

Example 13 N-ethyl-N- (β obtained in the same manner as in Example 1
-Hydroxyethyl) -m-toluidine (80.0 g, 0.447 mol) and a 50% aqueous sodium hydroxide solution (53.6 g, 0.670 mol) were charged into a magnetically stirred 500 ml autoclave, and purged with nitrogen. 24.8 g (0.491 mol) of methyl chloride was introduced at ± 1 kg / cm ² G. The introduction was completed in 2 hours, and then aging was performed at the same temperature for 10 hours.

After aging, the by-produced sodium chloride was removed by washing with water to obtain 84.5 g (0.438 mol) of N-ethyl-N- (β-methoxyethyl) m-toluidine (98% yield).

The content of this N-ethyl-N- (β-methoxyethyl) m-toluidine was analyzed by gas chromatography and found to be 98%.

Examples 14 to 18 In the same manner as in Example 13, the compounds shown in Table 3 were synthesized. The results are shown in Table 3.

[Effects of the Invention] The method for producing N, N-disubstituted anilines of the present invention provides a specific method by passing through N-substituted anilines obtained by reacting anilines with alkylene oxide.
A method for producing N, N-disubstituted anilines that can selectively produce N, N-disubstituted anilines. high temperature,
Since N, N-disubstituted anilines having various substituents can be selectively produced without requiring high pressure, N
-High yield of substituted aniline, and can be produced at low cost.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical indication location C07C 217/08 7457-4H C07C 217/08 217/84 7457-4H 217/84 // C07B 61 / 00 300 C07B 61/00 300

Claims (1)

(57) [Claims] 1. A compound of the general formula I (However, R in the formula represents H, Cl, NO ₂ or an alkyl group having 1 to 6 carbon atoms, an alkyloxy group or an alkenyl group, and the bonding position of R is ortho, meta or para with respect to —NH ₂₎ . Anilines represented by the general formula II (Wherein, R ¹ represents H, CH ₃ or CH ₂ Cl, and R ² represents H or CH ₃ ). (Wherein, R in the formula, R ¹ and R ² represent. The same as described above) to produce the N- substituted aniline derivative represented by, after separation of this, the general formula III R ³ -X (where Wherein R ³ represents an alkyl or alkenyl group having 1 to 6 carbon atoms and X represents a halogen.) An organic halide represented by the general formula IV characterized by reacting in the presence of a deoxidizing agent. (However, R, R ¹ , R ² and R ³ in the formula are the same as described above, and R ⁴ is H or R ^3. ) A method for producing an N, N-disubstituted aniline represented by the formula: