WO1995009148A1

WO1995009148A1 - Process for producing 4-aminodiphenylamine

Info

Publication number: WO1995009148A1
Application number: PCT/JP1994/001612
Authority: WO
Inventors: Toshio Yoshizawa; Kenta Ueyama; Makoto Igarashi; Masaki Sasaki; Harukichi Kano; Yataro Ichikawa
Original assignee: Seiko Kagaku Kabushiki Kaisha
Priority date: 1993-09-30
Filing date: 1994-09-29
Publication date: 1995-04-06
Also published as: JPH07149695A

Abstract

A process for producing directly a 4-aminodiphenylamine by reacting an aniline with an azobenzene in the presence of a base, wherein the yield and selectivity of the 4-aminodiphenylamine are improved by using a suitably selected solvent.

Description

Specification

4.Amino diphenylamines production method

The present invention relates to a method for producing 41-aminodiphenylamines by reacting anilines with azobenzenes. Background art

41-Aminodidiphenylamines are important compounds as intermediates for rubber aging inhibitors and azo dyes, and have been produced by various methods in the past.

For example, Japanese Patent Application Laid-Open No. 59-82349 discloses that diphenylamine is reacted with an acid and a nitrite to form N-2-nitrosone, and is subjected to Fischer-Hep rearrangement in the presence of hydrogen chloride. A method for producing 4-aminodiphenylamine by producing torosodiphenylamine and reducing it is described.

Also, Ger. Patent 1,856,633 discloses that by reacting p- 12-chlorochlorobenzene with aniline to produce 4- 12-nitrodiphenylamine, and reducing this to obtain 4- A method for producing aminodiphenylamine is described.

US Pat. No. 5,117,063 discloses that aniline and nitrobenzene are reacted in the presence of a base such as tetramethylammonium hydroxide to form 412-trosodiphenylamine and 412-trifluorophenylamine. A method for producing 41-aminodiphenylamine by producing and reducing these. Have been.

In such a conventional technique, the method disclosed in Japanese Patent Application Laid-Open No. 59-82349 has a high yield, but not only requires many reaction steps, but also uses a stoichiometrically large amount of auxiliary materials. However, they generate waste, and their disposal is very expensive.

The method disclosed in Ger. Patent No. 1 856 63 uses p-nitrochlorobenzene as a raw material. However, in this method, 0-nitrochlorobenzene is produced as a by-product. It is unavoidable and needs to be balanced with demand, which is not economically favorable.

Furthermore, the method disclosed in US Pat. No. 5,171,063 is carried out with dinitrobenzene and aniline, which are easily available as starting materials, but is expensive, for example, as a catalyst. A large amount of tetramethylammonium hydroxide is used, and it is difficult to collect and use it.

Therefore, in each of the above-mentioned prior arts, in each case, 4-2-torosodiphenylamine—412-trifluorodiphenylamine is produced as an intermediate, and these need to be reduced, and if only additional steps are required, However, there was a problem that expensive precious metal catalysts had to be used. Disclosure of the invention

The present invention provides an efficient method for producing 41-aminodifluoroamines by reducing the number of steps and producing intermediates without using expensive precious metal catalysts. Its purpose is to prevent waste from being generated by using it, and to increase economic efficiency by not producing by-products. As a result of various studies in view of the above circumstances, the present inventors have found that by reacting anilines with azobenzenes in the presence of a base, 41-aminodiphenylamines are directly produced in one step. Furthermore, they have found that 41-aminodiphenylamines can be produced in high yield by selecting a solvent, and have completed the present invention.

The present invention is a process for producing 41-aminodiphenylamines, which comprises reacting anilines with azobenzenes in the presence of a base. In this case, the reaction formula is shown by the following I.

The anilines used in the present invention are compounds represented by the general formula π.

In the formula, R ¹ is hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a halogen group, a cyano group, or the like. Concrete Examples are: ο—toluidine, m—toluidine, p—toluidine, 0—anisidine, m—anisidine, p—anisidine, 0—aminobenzonitrile, m—aminobenzonitrile And p-aminobenzonitrino, 0-chloroaniline, m-chloroaniline, p-chloroaniline and the like.

As the azobenzenes used in the present invention, compounds represented by the general formula m and having no substituent at the para-position are used.

In the formula, R ² and R ³ include hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a halogen group, a cyano group and the like. Specific examples include 2,2'-dimethylthiobenzene, 3,3'-dimethylazobenzene, 2,2'-dimethoxyazobenzene, and 3,3'dimethyloxybenzene.

Examples of the base used in the present invention include alkali and alkaline earth metals, alkaline and alkaline earth amides, alkaline and alkaline earth alkoxides, and alkaline earth alkoxides. And alkaline earth hydroxides, alkaline metal amides, alkaline metal hydrides, alkaline metal alkoxides and the like. Preferable examples include potassium metal, lithium hydroxide, cesium hydroxide, t-BuOK and the like.

The amount of the base used is not particularly limited, but it is preferable to use 0.5 or more in terms of the molar ratio of the base azobenzenes. In the above reaction, the desired product can be obtained without using a solvent. However, by selecting and using an appropriate catalyst, the formation of 2-aminodiphenylamines as a by-product is suppressed, and It is preferable to use a solvent because the yield of minodiphenylamines can be greatly increased.

As such a solvent, a non-brotonic dipolar solvent is preferable, and as specific examples, glymes and derivatives thereof are preferable. As such solvents, diglyme and derivatives thereof are more preferable. Triglyme and its derivatives.

The amount of the solvent used is not particularly limited, but it is preferable to use 5 or more in terms of the molar ratio of the solvent Zazobenzenes.

The reaction temperature is generally not lower than room temperature, preferably not lower than 100 ° C, and particularly preferably from 120 ° C to 180 ° C. C. In general, the higher the reaction temperature, the higher the yield. However, if the reaction temperature is too high, decomposition may be considered.

The molar ratio of the aniline to the azobenzene may be any ratio, but the molar ratio of the aniline to the azobenzene is preferably 5 to 20 times.

As the reaction atmosphere, the reaction can be performed in an atmosphere of an inert gas such as nitrogen, argon, and helium. In particular, when the reaction is performed in a hydrogen atmosphere, the reaction of 41-aminodiphenylamines can be performed. The yield can be increased.

The 4-aminodiphenylamines produced by the above reaction can be easily separated and obtained by distillation. BEST MODE FOR CARRYING OUT THE INVENTION Examples 1 to 14 of the present invention are shown below, and the results are summarized in Table 1. In Table 1, Azo is azobenzene, 4A is 4-aminodiphenylamine, 2A is 2-aminodiphenylamine, and 41 PADPA is 4-phenylazodiphenylamine. Is shown. In Table 1, 4 A selectivity = 4 A yield Z (4 A yield + 2 A yield) XI 00, and 4 A component yield = 4 A yield + 4 P AD PA yield Represents the rate.

Note that the present invention is not limited to the embodiments described below. (Example 1)

In a four-necked round-bottomed flask equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen inlet tube, 18.2 g (0.1 mol) of azobenzene, 2 g (0.1 mol) of t-BuOK II. mol), Aniri emissions 9 3 g (1. 0 mol) and ethylene glycidyl as the solvent Korujime Chirue - ether (monoglyme) were charged 75 m l, 5 in 1 40 ^e C while flowing at a flow rate of the nitrogen gas 50 m l Zm in A time reaction was performed. The reaction products were quantitatively analyzed by gas chromatography, and their identification was performed by comparing the retention times of gas chromatograms and using GC / MS.

As a result of analysis, no unreacted azobenzene was detected, and the products were 26% of 4-aminodiphenylamine, 20% of 2-aminodiphenylamine, and 4-aminodiphenylamine. 33% (all based on azobenzene). The selectivity of 4 A was 56%.

(Example 2)

The procedure was performed under the same conditions as in Example 1 except that the solvent was ethylene glycol getyl ether (a derivative of monoglyme). Unreasonable No azobenzene was detected, and the products were: 41-aminodiphenylamine 38%, 2-aminodiphenylamine 19%, 4-phenylazodiunylamine 23 % (All yields based on azobenzene). The selectivity for 4 A was 67%.

(Example 3)

The procedure was carried out under the same conditions as in Example 1 except that the solvent was ethylene glycol di-n-butyl ether (a monogram derivative). Unreacted azobenzene was not detected, and the product was 4-aminophenyldiamine 31%, 2-aminodiphenylamine 25%, 4-phenylazodiphenylamine 20% (All were based on azobenzen). The selectivity of 4 A was 55%.

(Example 4)

The procedure was performed under the same conditions as in Example 1 except that the solvent was diethylene glycol dimethyl ether (diglyme). Unreacted azobenzene was not detected, and the products were 41% aminodiphenylamine, 50% 2-aminodiphenylamine, 8%, and 4-unylazodiphenylamine, 26% (all based on azobenzene). (Yield). The selectivity of 4 A was 87%.

(Example 5)

The procedure was performed under the same conditions as in Example 1 except that the solvent was diethylene glycol getyl ether (a derivative of diglyme). No unreacted azobenzene was detected, and the products were: 41-aminodiphenylamine 55%, 2-aminodiphenylamine 5%, 4-phenylazodiphenyl Amine was 12% (all yields based on azobenzene). The selectivity of 4 A was 92%. (Example 6)

The procedure was performed under the same conditions as in Example 1 except that the solvent was diethylene glycol di-n-butyl ether (a derivative of diglyme). No unreacted azobenzene was detected, and the products were 41% aminodiphenylamine 48%, 2-aminodiphenylamine 9%, 41% phenylazodiphenylamine 10% ( All were yields based on azobenzene). The selectivity of 4 A was 85%.

(Example 7)

The procedure was carried out under the same conditions as in Example 1 except that the solvent was triethylene glycol dimethyl ether (triglyme). Unreacted azobenzene and 2-aminodiphenylamine were not detected, and the products were 4-aminodiphenylamine 64% and 4-phenylazodiphenylamine 17% (both based on azobenzene) Met. The selectivity of 4 A was 100%.

(Example 8)

The procedure was performed under the same conditions as in Example 1 except that the solvent was triethylene glycol getyl ether (a derivative of triglyceride). Unreacted azobenzene and 2-aminodiphenylamine were not detected, and the products were 4-aminophenyldiamine 65%, 4-phenylazodiphenylamine 5% (both azobenzene (Standard yield). The selectivity of 4 A was 100%.

(Example 9)

The procedure was carried out under the same conditions as in Example 1 except that the solvent was triethylene glycol di-n-butyl ether (triglyme derivative). No unreacted azobenzene was detected, and the products were 4-aminodiphenylamine 50%, 2-aminodiphenylamine 4%, 4 1-phenylazodiphenylamine 22% (all yields based on azobenzene). The selectivity of 4 A was 93%.

(Example 10)

The procedure was carried out under the same conditions as in Example 1 except that the solvent was tetraethylene glycol dimethyl ether (tetragram). Unreacted azobenzene was present at 15%, and the products were 41-aminodiphenylamine, 24%, and 2-aminodiphenylamine, 6% (both based on azobenzene). The selectivity of 4 A was 79%.

(Example 11)

The solvent and the oxygenate Tokishime Tan, except that the reaction temperature was 1 1 5 ^e C were performed under the same conditions as in Example 7. 17% of unreacted azobenzene is present, and the products are 41% aminodiphenylamine, 2% 2-aminodiphenylamine, 32%, and 4-aminodiphenylamine 36 % (All yields based on azobenzene). The selectivity for 4 A was 26%.

(Example 12)

5 00 ml pressure-resistant O one Toku slave to the reaction vessel using, except that was injected hydrogen gas to 1 0 k gZ cm ² G was performed in the same manner as in Example 7. Unreacted azobenzene was not detected, and the product was only 4-aminodiphenylamine 82% (yield based on azobenzene).

(Example 13)

Use a 500 ml pressure vessel for the reaction vessel, and set the reaction temperature to 120. Is C, was injected hydrogen gas to 1 0 k gZ cm ² G Except for the above, the same procedure was performed as in Example 7. Unreacted azobenzene was not detected, and the products were 41-aminodiphenylamine, 6%, 2-aminodiphenylamine, 1%, 4-phenylazodiphenylamine. % (All yields based on azobenzene).

(Example 14)

Except that was injected with nitrogen gas to 1 O k gZ cm ² G and the atmospheric gas was performed in the same manner as in Example 1 2. Unreacted azobenzene was not detected, and the products consisted of 52% of 41-aminodiphenylamine, 1% of 2-aminodiphenylamine, 32% of 4-phenylazodiphenylamine (all in all) Yield based on azobenzene).

table 1

yield (%)

Example Solvent Reaction conditions 4 A selectivity 4 A component

Azo4A2A4-PAD PA {%) Yield (%)

1 Monoglyme 140 ° C 0 26 20 33 56 58

2 Ethylene glycol 140 ° C 0 38 19 23 67 60

3 Ethylene glycol 140 ° C 0 31 25 20 55 51 Di n-butyl ether

4 Ziglyme 140 ° C 0 50 8 26 87 76

5 Diethylene glycol 140. C 0 55 5 12 92 67 Jechnolet

6 Diethylene glycol 140 ° C 0 48 9 10 85 58 di n-butyl ether

7 Triglime 140 ° C 0 64 0 17 100 81

8 Triethylene glycol 140 ° C 0 65 0 5 100 70 Detinole

9 Triethylene glycol 140 ° C 0 50 4 22 93 72 Di n-butynole

10 tetragram 140. C 15 24 6 0 79 24

-11 Jetoxymethane 115. C 17 11 32 36 26 47

12 Triglyme Hydrogen gas, 140 ° C 0 82 0 0 100 82

13 Triglyme Hydrogen gas, 120 ° C 0 66 1 18 99 84

14 Triglyme Nitrogen gas, 120 ° C 0 52 1 32, 98 84

From Table 1, by selecting a solvent, the yield of 4-aminodiphenylamines can be changed, and a high yield can be obtained. In addition, it can be seen that the 4 A yield is higher in the reaction under the hydrogen gas atmosphere than in the reaction under the nitrogen gas atmosphere.

(Example 15)

The reaction temperature and the solvent were examined at 1.0 mol of aniline, 0.1 mol of azobenzene (Azo), 0.1 mol of base (t-BuOK), and 5 hours of reaction time. The results are shown in Table 2 below.

Table 2 shows that the higher the temperature, the better the 4 A yield and 4 A selectivity in many cases. Triglyme had good 4A yield and 4A selectivity. (Example 16)

Investigated the case where the mixing ratio of aniline, triglyme, and t-BuOK was changed at 0.1 mol of azobenzene (Az0), reaction temperature of 120 ° C, and reaction time of 5 hours. Was. The results are shown in Table 3 below.

00

From 1 to 4 in Table 3, it can be seen that the higher the triglyme, the better the 4A yield and 4A selectivity. Also, from 5 to 7 in Table 3, it can be seen that the higher the amount of aniline, the better the 4A yield and 4A selectivity. Also, from 8 to 9 in Table 3, it can be seen that the larger the amount of base, the better the 4A yield and 4A selectivity. However, from a comparison between 0.1 mol and 0.2 mol of the base, it is sufficient that the amount of the base is approximately equivalent to that of azobenzene.

(Example 17)

1.82 g (0.01 mol) of azobenzene in a four-neck round bottom flask equipped with a stirrer, reflux condenser and thermometer, t-Bu OK 1.12 g (0.01 mol ), as a Aniri down such p- Tolui gin (0.1 mol), and a condenser. then Riguraimu 1 0 m 1, reaction was conducted for 3 hours at 1 60 ^e C while introducing nitrogen gas.

As a result of the analysis, 7% of unreacted azobenzene was present, and 73% of 4-amino-1-4'-methyldiphenylamine (both based on azobenzene) was produced.

(Example 18)

The procedure was performed in the same manner as in Example 1 except that p-amino benzonitrile was used as anilines, the solvent was diglyme, and the reaction time was 8 hours. As a result of analysis, 31% of unreacted azobenzene was present, and 32% of 41-amino-4'-cyanodiphenylamine (based on azobenzene) was produced.

(Example 19)

The procedure was performed in the same manner as in Example 1 except that P-chloroaniline was used as anilines and the reaction time was 8 hours. As a result of analysis, unreacted azobenzene 23%, 4-amino-4'-cyanodiphenyl Ethylene 38% (based on azobenzene) was produced.

(Example 20)

The procedure was performed in the same manner as in Example 1 except that 3,3′-dimethylazobenzene was used as azobenzenes and aniline was used as anilines. As a result of analysis, 1% of unreacted 3,3'-dimethylazobenzene was present, and 76% of 2-methyl-41-aminodiphenylamine (based on 3,3'-dimethylazobenzene) was formed. did.

(Example 21)

Example 3 was carried out in the same manner as in Example 1 except that 3,3′-dimethyldimethylazobenzene was used as azobenzenes and p-chloroaniline was used as anilines, and the reaction time was 8 hours. As a result of analysis, 24% of unreacted 3,3′-dimethylazobenzene was present, and 4-amino-3- (methyl) 4′-chlorodiphenylamine 33% (3,3′-) (Based on dimethylazobenzene). Industrial applicability

According to the present invention, 41-aminodiphenylamines can be efficiently and inexpensively produced in one less step without using an expensive noble metal catalyst and without producing an intermediate. In addition, it is economical because no by-products or waste are generated, and the yield and selectivity of 4-aminodiphenylamines can be improved by selecting monoglyme, diglyme, triglyme, and tetraglyme as the solvent. In particular, when triglyme is used, a remarkably high yield and selectivity can be obtained.

Claims

The scope of the claims

1. A process for producing 41-aminodiphenylamines, which comprises reacting anilines with azobenzenes in the presence of a base.

2. The method for producing 41-aminodiphenylamines according to claim 1, wherein the base is an alkali metal alkoxide.

3. The method for producing 41-aminodiphenylamines according to claim 2, wherein the base is t-BuOK.

4. The method for producing 4-aminodiphenylamines according to claim 1, 2, or 3, wherein the reaction is carried out in the presence of a solvent that is a non-proton dipolar solvent. .

5. The method for producing 4-aminodiphenylamines according to claim 4, wherein the solvent used in the reaction is monoglyme or a derivative thereof.

6. The process for producing 41-aminodifuunilamines according to claim 4, wherein the solvent used in the reaction is diglyme or a derivative thereof.

7. The method for producing 4-aminodifuunylamines according to claim 4, wherein the solvent used in the reaction is triglyme or a derivative thereof.

8. The method for producing 4-aminodiphenylamines according to claim 4, wherein the solvent used in the reaction is tetraglyme or a derivative thereof.

9. The 4-amino according to claims 1, 2, 3, 5, 6, 7, or 8, wherein the reaction is carried out in a hydrogen gas atmosphere. A method for producing phenylamines.

10. The process for producing 41-aminodiphenylamines described in claim 4 wherein the reaction is carried out in a hydrogen gas atmosphere ο

1 1. The 41-amino according to claims 1, 2, 3, 5, 6, 7 or 8 characterized in that the reaction is carried out at a temperature of about 12 O: up to 180. A method for producing diphenylamines.

1 2. The reaction temperature of about 1 20 T; ~ 1 8 0 ^e 4 Ichia Mi Roh Jifuyunirua Mi emissions such production method of C that feature patent claimed claims 4 wherein you the performed at.

1 3. The reaction temperature about a 1 20 T; ~ 1 8 0 e 4 Ichia Mi Roh Jifuyunirua Mi emissions such manufacturing method for a range ninth claim of claims you and this and Toku徵done in C.

1 4. The process for producing 41-aminodifuunilamines according to claim 10, wherein the reaction is carried out at a temperature of about 120 ° C to 180 °.