JPH02288850A - Production of n,n-disubstituted aniline - Google Patents

Abstract

PURPOSE:To selectively obtain a specific N,N-disubstituted aniline by adding an alkylene oxide to an aniline to form an N-substituted aniline derivative which is then separated and reacted with an organic halide in the presence of an acid scavenger. CONSTITUTION:Firstly, an alkylene oxide is added to a compound of formula I (R is H, Cl, NO2, 1-6C alkyl, alkoxy or alkenyl, the binding site for R is o-, m- or p-site in relation to NH2) to form a compound of formula II (R<1> is H, CH3 or CH2Cl; R<2> is H or CH3). Thence, this compound is separated and reacted with a compound of formula R<3>-X (R<3> is 1-6C alkyl or alkenyl; X is halogen) in the presence of an acid scavenger, thus obtaining the objective compound of formula III useful as an intermediate for N,N-disubstituted p- phenylenediamines (raw materials for the main reagents for color developing solution or azo dyes) in high yield at low cost without the need for both high temperature and pressure.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing N,N-disubstituted anilines,
More specifically, it relates to a method for producing N,N-disubstituted anilines, which are intermediates for N,N-disubstituted p-phenylenediamines, which are useful as main ingredients for color developers and synthetic raw materials for azo dyes. .

[Prior art 1] N,N-disubstituted p-)ylenediamine, which is useful as a raw material for various industrial chemicals such as the main agent of color developers, is synthesized from N,N-disubstituted aniline, which is known as an intermediate thereof. There is.

Conventionally, the methods for synthesizing N,N-disubstituted anilines include:
A method of reacting an N-substituted aniline with an alkyl bromide for a long time (JP-A-47-11534 and JP-A-5
0-131526), ■ A method of reacting 1)-toluenesulfonic acid ester of a monoalkyl ether with N-substituted aniline (see Japanese Patent Application Laid-Open No. 1982-195849), and ■ A method of reacting anhydrous phosphate with N-substituted aniline. A method of reacting an N-substituted aniline with an alkyl chloride in the presence of (see Japanese Patent Publication No. 60-13023) is known.

[Problems to be Solved by the Invention] However, all of these synthesis methods use N-substituted aniline as a starting material, and this N-substituted aniline is produced by reacting an alcohol with an aniline. It is known that aniline can be obtained by separating and purifying a mixture of aniline and N,N-disubstituted aniline using methods such as vacuum distillation, but this requires high temperature and pressure as reaction conditions, and the same substituents Since a large amount of N,N-disubstituted aniline in which two substituents are bonded is produced as a by-product, the yield of N-substituted aniline in which two substituents are bonded is low, and therefore, it is an industrially disadvantageous synthesis method. , and the price was high.

[Means for Solving the Problems] The present invention provides a method for producing specific N,N-disubstituted anilines through N-substituted anilines obtained by reacting anilines with alkylene oxide. This is what I found.

That is, according to the present invention, -M formula I (wherein R is H, CL No.
6 represents an alkyloxy group or an alkenyl group, and the bonding position of H is ortho to -NH2,
Either the meta or para position is acceptable. ) Adding alkylene oxide to the anilines represented by formula II (wherein R in the formula represents the same as above, R1 represents H, CH3, CH, Cβ, and R2 represents H or C1
, represents. ) After producing an N-substituted aniline derivative represented by and separating it, - Formula III 3-X (wherein R3 represents an alkyl or alkenyl group having 1 to 6 carbon atoms, and X represents a halogen) ) by reacting an organic halide represented by formula (1) in the presence of a deoxidizing agent (where R, R', R2 and R3 in the formula are the same as above, and R4 is H or R3 ),
N-disubstituted anilines can be produced.

- General formula V in which R4 in formula (2) is H (however, R in the formula represents H, Cj, 2 N ports, or an alkyl group having 1 to 6 carbon atoms, an alkyloxy group, or an alkenyl group, and H
The bonding position may be at the ortho position, meta position, or para position with respect to -NH. Also, R1 is H, CH3, CH2
It represents Cl, and R2 represents H or CH3. ) to the N,N-disubstituted anilines represented by formula III
- Formula ■ (However, R in the formula represents the same as above, R1 is H, CH3, C
H2 (represents J, R2 represents H or CH, R3
and R6 each independently represent an alkyl group or alkenyl group having 1 to 6 carbon atoms. ) N,N-disubstituted anilines represented by the formula can be produced.

[Detailed Description of the Invention] (l l First reaction (addition reaction of alkylene oxide) Anilines In the present invention, the anilines of -formula (■) used as raw materials are those in which R is H, C1, NO□ or the number of carbon atoms 1~
5 is an alkyloxy group or an alkenyl group, and the bonding position of H may be any of the ortho position, meta position, and para position with respect to -NH2. Specific examples include aniline, toluidine, anisidine, nitroaniline, and chloroaniline.

The alkylene oxide added to the above anilines is as follows:
Examples include ethylene oxide, propylene oxide, isobutylene oxide, and epichlorohydrin, with ethylene oxide and propylene oxide being particularly suitable.

When adding hyalkylene acid to alkylene oxide, when adding 1 mole of alkylene oxide to 1 mole of aniline, the reaction molar ratio (aniline/alkylene oxide) should be 1.25 to 1, especially 2 to 1. 30 is preferable from the viewpoint of yield.

At this time, Lewis acid is used as a catalyst for anilines,
When 0.05 to 0.20% by weight is added, the yield is improved.

If the molar ratio is 10 or more, the yield per batch will be low, which is industrially disadvantageous.

In the case of a 1 mol alkylene oxide adduct, after the reaction is complete, unreacted anilines are separated and recovered by vacuum distillation, etc.
In the general formula, R1 represents H, CH3, C1, Cj, and R2 represents H or CH3. ) N-substituted anilines are obtained.

Specific examples of such N-substituted anilines include N-1
β-hydroxyethyl)-aniline N-(β-hydroxypropyl)-aniline N-[β-hydroxyethyl)
-Toluidine N-(β-hydroxypropyl)-Toluidine N-(β-hydroxyethyl)-anisidine N-1
β-hydroxypropyl)-anisidine Nlβ-hydroxyethyl)-nitroaniline N-(β-hydroxypropyl)-nitroaniline N-(β-hydroxyethyl)-chloroaniline N-(β-hydroxypropyl)-
Examples include chloroaniline.

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

Organic halides The organic halides used in this second reaction are:
It has the general formula %(), where R3 is an organic substituent and X is a halogen.

As such organic halides, organic bromides and organic iodides can be considered, but since organic bromides and organic iodides are expensive, it is better to use organic chlorides. Examples of such organic chlorides include methyl chloride, ethyl chloride, rhopropyl chloride, ethylene chlorohydrin,
Examples include methoxyethyl chloride.

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

The deoxidizing agent used in the present invention includes potassium carbonate, sodium carbonate, sodium phosphate, sodium hydrogen phosphate, sodium dihydrogen phosphate, potassium phosphate,
Potassium hydrogen phosphate, potassium dihydrogen phosphate, calcium phosphate, calcium hydrogen phosphate, calcium dihydrogen phosphate, potassium hydroxide, sodium hydroxide, etc., but among these, phosphates with low alkalinity When a deoxidizing agent is used, the N-alkylation reaction is the main reaction, and when a strong alkali such as potassium hydroxide or sodium hydroxide is used, even the hydroxyl group of formula 11 is alkylated.

Such a deoxidizing agent is usually used in the form of an aqueous solution, and is used in an amount such that its alkaline value is at least equimolar to the organic chloride.

In the present invention, an iodide compound can be added as a catalyst. Specific examples of such iodinated compounds include inorganic salts of iodine such as NaI and KI, and (2).

The amount of the iodide compound to be used is 0.00% as the theoretical amount of iodine for N-substituted aniline. It is preferably 1 to 0.2 times the mole of O, and most preferably 0.03 to 0.1 times the mole. Usage is 0
．． If the amount is less than 0.01 times the mole, the reaction time will be longer and the amount will be less than 0.01 times.
If it exceeds 2, the iodide compound is expensive and the catalyst cost becomes high.
50°C, preferably 30 to 10°C.

If the temperature is below 0°C, the reaction time will be longer;
If the temperature exceeds ℃, side reactions such as hydrolysis occur.

Neither is preferable. The reaction pressure is 5 kg/cm2G or less, preferably 2 to 4 kg/cm''G. Even if the reaction pressure exceeds 5 kg/cm2G, there is not much improvement effect.

In the second reaction, a solvent may be used, but unless there is a problem with the solubility of the raw materials, it is preferable to carry out the reaction without a solvent except for the aqueous deoxidizing agent solution.

This second reaction can proceed quantitatively in a short time by using the above-mentioned deoxidizing agent and an iodide compound as a catalyst.
Di-substituted anilines can be produced in high yield and at lower cost.

It is represented by N,N-disubstituted aniline produced in this way, and R, R', R2 and R3 in the formula are the same as above, and R4 is H or R3.

Specifically, when a weakly alkaline deoxidizing agent is used, R4 in the above formula (IV) is ■, and such N, N
-Disubstituted aniline includes, for example, N-methyl-N13
-hydroxyethyl)-aniline, N-ethyl-N-(
β-hydroxyethyl)-aniline, N-propyl-N
13-hydroxyethyl)-aniline, N-methyl-N
-(β-propyl)-aniline, N-ethyl-N-(β
-hydroxyprovir)-aniline, N-methyl-N16-hydroxyethyl)-toluidine, N-propyl-N-tβ-hydroxyethyl)-toluidine, N-methyl-N-(β-hydroxypropyl)
-toluidine, toluidine derivatives such as N-ethyl-N-(β-hydroxypropyl)-toluidine, N-methyl-N13-hydroxyethyl)-anisidine, N-ethyl-N-(β-hydroxyethyl)-anisidine, N
-Propyl-N-(β-hydroxyethyl)-anisidine, N-methyl-N-(β-hydroxypropyl)-anisidine, N-ethyl-N13-hydroxypropyl)-
Anisidine derivatives such as anisidiine, N-methyl-N
-(β-hydroxyethyl)-nitroaniline, N-ethyl-N-(β-hydroxyethyl)-nitroaniline, N-propyl-N-(β-hydroxyethyl)-nitroaniline, N-methyl-N- Nitroaniline derivatives such as (β-hydroxypropyl)-nitroaniline, N-ethyl-N-fβhydroxypropyl)-nitroaniline, N-methyl-N13-hydroxyethyl)-chloroaniline, N-ethyl-N-(β -hydroxyethyl)-chloroaniline, N-propyl-N-1β-hydroxyethyl)-chloroaniline, N-methyl-N-(β-hydroxypropyl)-chloroaniline, N-ethyl-N-
Examples include chloroaniline derivatives such as (β-hydroxypropyl)-chloroaniline.

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

(3) Third reaction (alkoxylation reaction) The N,N-disubstituted anilines thus obtained are
When R4 in the above-mentioned formula (IV) is H (the above-mentioned formula v), by further reacting an organic halide in the presence of a strong alkali, N having two different substituents,
N-disubstituted anilines can be produced.

II R'-X (wherein R5 is an alkyl or alkenyl group having 1 to 6 carbon atoms, and X is a halogen). Bromide and organic iodide are conceivable, but since organic bromide and organic iodide are expensive, it is better to use organic chloride. Examples of such organic chlorides include methyl chloride, ethyl chloride, n-propyl chloride, ethylene chlorohydrin, and methoxyethyl chloride.

1 liter Further, as the deoxidizing agent used at this time, strong alkaline compounds such as hydroxides of alkali and alkaline earth metals are used. Examples of such a deoxidizing agent include potassium hydroxide, sodium hydroxide, calcium hydroxide, barium hydroxide, etc. Among these, potassium hydroxide and sodium hydroxide are preferred.

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

[The conditions for the third reaction are the same as those for the second reaction (reaction temperature is 0 to 150°C, preferably 30-111°C).
It can be carried out at 0°C. If the temperature is below 0°C, the reaction time will become long, and if it exceeds 150°C, side reactions such as hydrolysis will occur, which is not preferable. Reaction pressure is 5kg
/c+n2G or less, preferably 2 to 4 kg/cm2G. Even if the reaction pressure exceeds 5 kg/cm2G, there is not much improvement effect.

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

Such a deoxidizing agent is usually used in the form of an aqueous solution, and is used in an amount equivalent to or more than the organic chloride based on its alkaline value, and
An iodide compound is used as a catalyst for N-substituted anilines. By using 1 to 0.2 times the mole of O, the reaction can proceed quantitatively in a short time, and thereby the target N,N-disubstituted anilines can be produced in high yield and at a lower cost. can be manufactured.

The general formula produced in this way (in the formula, R, R', R'' and R3 are the same as before, and R5 independently of R3 is an alkyl group or alkenyl group having 1 to 6 carbon atoms) Examples of the N,N-disubstituted anilines include N-ethyl-N-(β-
Anilines such as methoxyethyl)-aniline, N-ethyl-N-(β-methoxypropyl)-aniline, N-methyl-N-(βI-ethoxyethyl)-aniline, N-methyl-N-(β-ethoxypropyl)-aniline Derivatives, N-ethyl-N-(β-methoxyethyl)-toluidine, N-ethyl-N-1β-methoxypropyl)-toluidine, N-methyl-N-fβ-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-Nlβ-methoxyethyl)-nitroaniline, N-ethyl-N-(β-methoxyethyl)-nitroaniline, N-methyl-N-(β-ethoxyethyl)-
Nitroaniline derivatives such as nitroanniline, N-methyl-N-(β-ethoxypropyl)-nitroaniline, N-methyl-N-(β-ethoxyethyl)-chloroaniline, N-ethyl-N-(β- methoxyethyl)-chloroaniline, N-ethyl-N-fβ-methoxypropyl)chloroaniline, N-methyl-N-(β-ethoxyethyl)-chloroaniline, N-methyl-N-(β-ethoxypropyl)- Examples include chloroaniline derivatives such as chloroaniline.

[Example] Next, the present invention will be specifically explained with reference to Examples.

Example 1 ■ Addition reaction of alkylene oxide 249.1 g (2.33 mol) of m-toluidine was placed in a 500 ml autoclave with electromagnetic stirring, and after purging the inside of the container with nitrogen gas, the reaction temperature was raised to 110 ± 5°C to initiate oxidation. Ethylene (38.0 g fO, 8639 mol) was introduced. The introduction was completed in 10 minutes, and ripening was carried out at the same temperature for 30 minutes.

Thereafter, unreacted m-toluidine was recovered by vacuum distillation to obtain N-(β-hydroxyethyl l-m-toluidine 128.2 gf0.849 mol) (yield 98% based on ethylene oxide).

When the content of this N-(β-hydroxyethyl 1m-toluidine was analyzed by gas chromatography, it was found that 9
It was 8%.

■N-alkylation reaction N16-hydroxyethyl)- obtained in the reaction of (■) above
m-Toluidine 72.0g (0,477mol), 30
% trisodium phosphate aqueous solution 155.0 g (0,28
4 mol) and potassium iodide 2.4gf0.014 mol) were placed in a magnetic stirring type 500mj autoclave, and after purging the inside of the container with nitrogen gas, the reaction conditions were set to 100±5°C.
, pressure 3±l kg/cm2G and ethyl chloride 40.
5 g (0,628 mol) were introduced. The introduction was completed in 4 hours, and then aging was carried out at the same temperature for 6 hours. After ripening, the by-produced NaCR was removed by washing with water, and N-ethyl-
N-fβ-hydroxyethyl-m-toluidine 82.6
g (0,461 mol) was obtained (yield 97%).

The content of this N-ethyl-N-1β-hydroxyethyl-m-toluidine was analyzed by gas chromatography and found to be 96%.

Examples 2-6 In the same manner as in Example 1, the compounds shown in the table below were synthesized.

The results are shown in Table 1.

Example 7 ■ Addition reaction of alkylene oxide 249.1 g (2.33 mol) of m-toluidine was placed in a 500 ml autoclave with electromagnetic stirring, and after purging 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 ripening was carried out at the same temperature for 30 minutes.

Thereafter, unreacted m-toluidine was recovered by vacuum distillation, and N-(β-hydroxyethyl) m-toluidine 12
8.2 gf0.849 mol) (yield 98%/EO
).

The content of N-(β-hydroxyethyl)-m-)luidine 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 reaction of (1) above and 114.5 g (
After charging 1,43 mol) into a magnetic stirring type 500mj autoclave and replacing it with nitrogen, the reaction conditions were set to 60±5.
℃, 3±1 kg/cm2G and methyl chloride 53.0
g fl, 05 mol) was introduced. The installation was completed in 3 hours. Thereafter, aging was performed at the same temperature for 9 hours.

After the aging, the by-produced monohelium chloride was removed by washing with water to obtain 8.2.4 g (10.460 mol) of N-methyl-N-(β-methoxyethyl) m-toluidine (yield 98%). ).

The content of this N-methyl-N-1β-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-hydroxyethyl)-m-toluidine obtained in the same manner as in Example 1 80. OgfO,4
47 mol) and 50% aqueous sodium hydroxide solution 53.6
g +0.670 mol) was charged into a 500mj electromagnetic stirring autoclave, and after purging with nitrogen, the reaction conditions were adjusted to 60±
Methyl chloride at 5°C, 3±l kg/cm”G 24.
8 g (0,491 mol) were introduced. The introduction was completed in 2 hours, and then aging was carried out at the same temperature for 10 hours.

After completion of the ripening, by-produced sodium chloride was removed by washing with water to obtain N-ethyl-N-(β-methoxyethyl)m-toluidine (84.5 g fo, 438 mol) (yield: 9
8%).

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

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

2nd [Effect of the Invention] The method for producing N,N-disubstituted anilines of the present invention allows specific N, This is a method for producing N,N-disubstituted anilines that can selectively produce N-disubstituted anilines.
, compared to the synthesis method of N-disubstituted aniline, it does not require high temperature or high pressure in the reaction conditions, and it is possible to selectively produce N,N-disubstituted aniline having various substituents. , the yield of N-substituted aniline is high and it can be produced at low cost.

Claims (2)

[Claims] (1) General formula I ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, R in the formula is H, Cl, NO_2 or carbon number 1
~6 alkyl group represents an alkyloxy group or an alkenyl group, and the bonding position of R may be any of the ortho position, meta position, and para position with respect to -NH_2. ) By adding alkylene oxide to the anilines represented by the formula II, there are mathematical formulas, chemical formulas, tables, etc. (However, R in the formula represents the same thing as above, and R^1
represents H, CH_3, CH_2Cl, and R^2 represents H or CH_3. ) After producing an N-substituted aniline derivative represented by and separating it, the general formula III R^3-X (wherein R^3 is an alkyl or alkenyl group having 1 to 6 carbon atoms, represents a halogen.) General formula IV, which is characterized by reacting an organic halide represented by the following in the presence of a deoxidizing agent ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, R, R in the formula ^1, R^2 and R^3 are the same as above, and R^4 is H or R^3.) A method for producing N,N-disubstituted anilines. (2) General formula V ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, R in the formula is H, Cl, NO_2 or carbon number 1
~6 alkyl group represents an alkyloxy group or an alkenyl group, and the bonding position of R may be any of the ortho position, meta position, and para position with respect to -NH_2. Further, R^1 represents H, CH_3, CH_2Cl, and R^2 represents H or CH_3. ) to the N,N-disubstituted anilines represented by the general formula IIIR
^5-X (However, R^5 in the formula represents an alkyl or alkenyl group having 1 to 6 carbon atoms, and X represents a halogen.) Reacting an organic halide represented by the following in the presence of a strong alkali. There are general formulas VI▲mathematical formulas, chemical formulas, tables, etc.▼ (However, R in the formula represents the same thing as above, and R^1
represents H, CH_3, CH_2Cl, R^2 represents H or CH_3, and R^3 and R^5 each independently represent an alkyl group or alkenyl group having 1 to 6 carbon atoms. ) A method for producing N,N-disubstituted anilines represented by: