JPH10168038A - Production of diaminodiphenylamine derivative useful as degradation preventing agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject compound having antioxidation property and anti-ozone property and useful as a degradation preventing agent by the reducing alkylation of dinitrodiphenylamine or diaminodiphenylamine with a ketone in the presence of a hydrogenation catalyst under hydrogen pressure. SOLUTION: The objective compound of the formula RNHC6 H4 NHC6 H4 NHR (R is an alkyl, a cycloalkyl or methylbenzyl) is produced by the reducing alkylation of dinitrodiphenylamine or diaminodiphenylamine with a ketone (e.g. acetone or methyl ethyl ketone) in the presence of a hydrogenation catalyst (e.g. platinum/carbon or copper-chromium catalyst) under hydrogen pressure (working pressure: 50-100kg/cm<2> ) preferably at 50-120 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The diaminodiphenylamine derivative according to the present invention is used in a field where it is necessary to prevent oxidation or ozone deterioration of rubber or plastic which is susceptible to oxidative deterioration or ozone deterioration.

[0002]

2. Description of the Related Art As agents for preventing oxidative deterioration or ozone deterioration, there are phenol-based deterioration inhibitors and amine-based deterioration inhibitors. Particularly effective amine-based deterioration inhibitors are diphenylamine derivatives and p-phenylenediamine derivatives. Has been used, but its effect has not been sufficient.

[0003]

The diphenylamine derivative and the p-phenylenediamine derivative which have been conventionally used have one or two nitrogen atoms exhibiting antioxidant and antiozonant functions in the molecule. But the effect is not enough yet. Therefore, in order to enhance the effect over the conventional diphenylamine derivative or p-phenylenediamine derivative, it is necessary to create a compound having three or more nitrogen atoms in the molecule that enhances the antioxidant and antiozonant effect. Was.

[0004]

As a means for producing a diaminodiphenylamine derivative as a drug exhibiting a higher deterioration preventing effect, dinitrodiphenylamine or diaminodiphenylamine is used as a raw material in the presence of necessary ketones and a hydrogenation catalyst. An attempt was made to produce the desired diaminodiphenylamine derivative by performing reductive alkylation under hydrogen pressure. Diamino diphenylamine derivative is represented by _{RNHC 6 H 4 NHC 6 H 4} NHR consisting formula. In this case, R includes an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group, and a methylbenzyl group. Examples of the ketones include aliphatic ketones acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl isopropyl ketone, methyl-n-butyl ketone (2-hexanone), methyl isobutyl ketone, medityl oxide, methyl-t-butyl ketone (3 , 3-dimethyl-2
-Butanone), methylpentyl ketone (2-heptanone), ethylbutyl ketone (3-heptanone), methylhexyl ketone-2-octanone), methyl isoamyl ketone (5-methyl-2-hexanone), methyl-n-
Heptyl ketone, 5-methyl-3-heptanone (ethyl-3-methylbutanone), diethyl ketone (3-pentanone), di-n-propyl ketone (4-heptanone),
Alicyclic ketones such as cyclohexanone and methylcyclohexanone, and aromatic acetophenone are used.
As the catalyst, a platinum / carbon, copper chromium catalyst or nickel catalyst is used. Depending on the reaction pressure and the hydrogen pressure, the higher pressure can terminate the reaction in a shorter time, but usually the normal pressure of the autoclave is 50 to 100.
It is performed at kg / cm ² . In addition, the reaction temperature is from room temperature, but a higher force is preferable in relation to the reaction rate, and it is generally related to the activity of the catalyst and the amount of the catalyst used.
20 ° C. is used.

[0005]

The diaminodiphenylamine derivative according to the present invention can be easily prepared by subjecting dinitrodiphenylamine and diaminodiphenylamine as starting materials to reductive amination under pressure of ketones and hydrogen in the presence of a hydrogenation catalyst as shown in the following Examples. It was confirmed that the desired product was obtained.

[0006]

Example 1 In an autoclave, 51.8 g of 4,4'-dinitrodiphenylamine [0.2 ^M ], 1.0 g of a platinum / carbon catalyst [hereinafter, Pt / C], and methyl isobutyl ketone [2 × 0.2 M × 4] ], And after three times of nitrogen substitution, hydrogen is pressurized to 100 kg / cm ² and reductive alkylation is performed at a temperature of 80 to 110 ° C. Once the hydrogen pressure drop stops, it is cooled and purged with hydrogen, the contents are filtered to remove the catalyst, and the filtrate is concentrated in vacuo to completely remove volatile components. There was obtained 73.5 g (100.1%) of 4,4'-bis (1,3-dimethylbutylamino) diphenylamine as a dark purple brown viscous liquid.

[0007]

Example 2 In an autoclave, 4,4 'diaminodiphenylamine (hereinafter referred to as DADPA) [0.2 ^M ] 39.8.
g, acetone [2 × 0.2 ^M × 8] 185.6 g, Pt
/ C 1.0 g, 100 kg / c according to Example 1
After charging m ² of hydrogen, reductive alkylation is carried out at 80 to 110 ° C. until the absorption of hydrogen stops. After cooling, the catalyst was removed by filtration and then the volatile components were completely removed under reduced pressure to obtain 56.5 g (99.8%) of 4,4'-bis (isopropylamino) diphenylamine as a dark purple brown viscous liquid. Was. Since this solidified on standing, it was recrystallized from isopropanol / water [2/1] to give mp 68.5-6.
Red-purple-brown crystals at 9.7 ° C. were obtained.

[0008]

Example 3 DADPA [0.2 ^M ] was added to an autoclave.
39.8 g, methyl ethyl ketone [2 × 0.2 ^M × 6]
After charging 172.8 g and 1.0 g of Pt / C, and charging 100 kg / cm ² of hydrogen according to Example 1, 80-1
Reductive alkylation is carried out at 00 ° C. until hydrogen absorption stops. After cooling, the catalyst was removed, the volatile components were completely removed under reduced pressure, and the dark purple-brown viscous liquid 4,4′-bis (se
c. 62.0 g of butylamino) diphenylamine (9
9.7%).

[0009]

Example 4 39.8 g of DADPA [0.2 ^M ], methyl isobutyl ketone [2 × 0.2 ^M × 4] 160.0
g, 1.0 g of Pt / C was subjected to reductive alkylation according to Example 1, and 72.9 g (99.3%) of a dark purple brown viscous liquid was obtained.
I got

[0010]

Example 5 39.8 g of DADPA [0.2 ^M ], methyl-n-hexyl ketone [2 × 0.2 ^M × 4]
8 g and 1.0 g of Pt / C were subjected to reductive alkylation according to Example 1 to obtain a dark purple-brown viscous liquid 4,4′-bis (1-
Methyl-n-heptylamino) diphenylamine84.
5 g (99.9%) were obtained.

[0011]

Example 6 39.8 g of DADPA [0.2 ^M ], 156.8 g of cyclohexanone [2 × 0.2 ^M × 4], Pt
/ C was subjected to reductive alkylation according to Example 1 to obtain 73.4 g (9,9 ′) of 4,4′-service (cyclohexylamino) diphenylamine as a dark purple brown viscous liquid.
9.7%). Since this solidified on standing, it was recrystallized from isopropanol / water [4/1] to give m
Purple crystals of p109.5-110.5 ° C were obtained.

[0012]

From the above results, it is found that diaminodiphenylamine derivatives can be easily obtained by using dinitrodiphenylamine and diaminodiphenylamine as raw materials and subjecting them to reductive alkylation with ketones under hydrogen pressure in the presence of a hydrogenation catalyst. I was assured.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 101/00 C08L 101/00

Claims (1)

[Claims] A reductive alkylation of dinitrodiphenylamine or diaminodiphenylamine in the presence of a ketone and a hydrogenation catalyst under hydrogen pressure to obtain a compound represented by the general formula RNHC ₆ H ₄ NHC ₆ H ₄ NHR (wherein R is alkyl A diaminodiphenylamine derivative represented by a group represented by the following formula: