KR950013254B1 - Aromatic diamine compounds and process for preparing it - Google Patents

Abstract

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Description

Aromatic diamine compound and preparation method thereof

The present invention relates to a novel aromatic diamine compound and a method for producing the same, in particular a novel aromatic diamine compound having a tetraphenylfuran structure and a method for producing the same.

All aromatic polyamides and polyamides that have been used conventionally have excellent mechanical properties along with excellent heat resistance and are used in a wide range of industrial materials, but most of them are insoluble in organic solvents and have many problems in their moldability. Among these resins, polyimides or polyamides prepared from diamino tetraphenyldiophene as raw materials are known to be soluble in organic solvents (see, for example, Y. Imai et al, J. Pplym. Sci., Polym. Chem). Ed., 22, 2189 (1 984), ibid, 23, 1797 (1985)).

Therefore, it can be considered that a heat-resistant resin having excellent moldability soluble in an organic solvent can be obtained by using diaminotetraphenylfuran in place of the diaminotetraphenyldiophene, but such aromatic diamines are not known at present.

The present invention provides a novel aromatic diamine compound having a novel aromatic diamine, in particular a tetraphenylfuran skeleton, in which such industrial utility is foreseen, and also provides a method for producing the same.

The present inventors have intensively studied a method for obtaining such a novel aromatic diamine compound. As a result, paranitrobenzyl phenyl ketone is used as a starting material, and it is passed through bis (nitrophenyl) dibenzoylethane and bisnitrophenyl diphenylfuran. The present invention was completed by confirming that a novel aromatic diamine compound suitable for the purpose of the invention was obtained by using the synthesis method.

1st invention of this invention is general formula (I)

It is an aromatic diamine compound represented by.

According to a second aspect of the present invention, a diketone compound is prepared by paranitrobenzylphenyl ketone by an oxidative coupling reaction, and a dinitrofuran compound is prepared by dehydration cyclization and reduced thereto. It is a method of manufacturing the aromatic diamine compound represented by the said General formula (I) characterized by the above-mentioned.

Paranitrobenzylphenyl ketone of the following general formula (II) which is a starting material according to the present invention

Silver is easily synthesized by Friedel-Krafts reaction of nitrophenylacetyl chloride with benzene.

General formula (III)

The diketone compound represented by is obtained by treating the ketone compound represented by the general formula (II) with a base and carrying out oxidative coupling with halogen. Examples of the base used herein include a base having the ability to substitute hydrogen at the benzyl group position, and include sodium metal, potassium metal, sodium hydride, potassium hydride, sodium methoxide, sodium ethoxide, potassium methoxide and potassium. Toxide, potassium butoxide, ethylmagnesium bromide, butyl lithium, isopropyl magnesium bromide, lithium diisopropylamide, sodium amide and the like are used. Of these, sodium methoxide and sodium ethoxide are particularly preferred. In addition, as the halogen element, iodine or bromine is particularly preferable. In fact, in order to manufacture the diketone compound represented by the general formula (III), the ketone compound represented by the general formula (II) may be reacted with sodium ethoxide, followed by reaction with iodine. The amount of sodium ethoxide used in this reaction is 1 to 2 equivalents relative to the ketone compound, and the amount of iodine is appropriately 0.5 to 2 equivalents. In addition, although reaction temperature can be -30-100 degreeC, although it depends largely on an economy, it is good to make reaction from tens of minutes.

General formula (Ⅳ)

The dinitrofuran compound represented by is obtained by subjecting the diketone compound represented by the general formula (III) to dehydration ring reaction under acidic conditions. Acids used herein include hydrochloric acid, hydrochloric acid, sulfuric acid, polyphosphoric acid, and the like, but hydrochloric acid is particularly preferred.

In fact, the diketone compound represented by the general formula (III) may be heated in the presence of hydrochloric acid. At this time, although reaction temperature is 0-200 degreeC, it is preferable to react at the temperature of 30-150 degreeC economically. In addition, although a wide range of organic solvents can be used as a solvent used for this reaction, acetic acid is especially preferable. The reaction time depends greatly on the amount of reagent used, the kind of the solvent, the reaction temperature, and the like, but the reaction time is preferably several tens of minutes.

On the other hand, the aromatic diamine compound represented by general formula (I) can be obtained by reducing using the dinitro compound represented by general formula (IV) as a reducing agent.

Examples of the reducing agent used herein include hydrogen, iron-hydrochloride, stannous chloride-hydrochloric acid and zinc-acetic acid. In particular, this reaction is preferably a catalytic reduction hydrogenation method or a stannous chloride-hydrochloric acid method.

The present invention provides an aromatic diamine compound represented by general formula (I) and an advantageous method for producing the same.

Conventionally, since most heat-resistant resins, such as all aromatic polyamides prepared from aromatic diamine compounds as raw materials, have low solubility in many organic solvents, moldability is difficult, but the diamine compound of general formula (I) of the present invention The heat-resistant resin prepared from the raw material is soluble in an organic solvent, so it is easy to be molded and has excellent heat resistance electrical and mechanical properties, and thus has great value as an industrial material.

Hereinafter, the present invention will be described through Examples.

Example 1

Synthesis of 1,2-bis (4-nitrophenyl) -1,2-dibenzoylethane

105 g (0,435 mol) of paranitrobenzylphenyl ketone are dispersed in 300 ml of dehydrated ethanol, and a small amount of 10 g (0.435 mol atom) of sodium metal is added at room temperature to obtain a purple solution.

To this, 200 ml of dehydrated ethanol was added, and then 500 ml of an ether solution in which 55.2 g (0.218 mol) of iodine was dissolved was added dropwise while stirring at 0 ° C. for about 2 hours, and then reacted by stirring at room temperature for 2 hours. After the reaction, the solvent is removed, the residual solid is washed with distilled water, dried and then recrystallized with chloroform to obtain white needle crystals. Yield is 82 g (yield 78%).

Melting Point: 232-233 ℃

Infrared Absorption Spectrum (KBr): 1660cm ^-1 (C = 0)

¹ H-NMR (CDCI ₃ ): 8.1-7.2 (M, 18H), 5.6ppm (s, 2H)

Elemental Analysis Value: Carbon Hydrogen Nitrogen

Calculation: 69.90 4.20 5.80

Found (%): 69.60 3.91 5.70

Example 2

Synthesis of 3,4-bis (4-nitrophenyl) -2,5-diphenylfuran

82 g (0.17 mol) of 1,2-bis (4-nitrophenyl) -1,2-dibenzoylethane are dissolved in glacial acetic acid (600 ml).

The solution is stirred for 2 hours while blowing hydrochloric acid gas at a temperature of 90 ° C. The reaction solution thus obtained is introduced into a large amount of distilled water, the yellow precipitate is filtered and dried, and recrystallized with glacial acetic acid to give a yellowish plate crystal.

Yield is 67 g (85% yield).

Melting Point: 292-293 ℃

Infrared Absorption Spectrum (KBr): Absorption of 1660cm ^-1 (C = 0) is lost.

¹ H-NMR (CDCI ₃ ): (dimethylsulfoxide-d ₆ ) 8.15 (d, 4H), 7.5-7.2 ppm (m, 14H)

Elemental Analysis Value: Carbon Hydrogen Nitrogen

Calculation: 72.70 3.90 6.06

Found (%): 72.40 3.67 6.02

Example 3

Synthesis of 3,4-bis (4-aninophenyl) -2,5-diphenylfuran (tin chloride method)

67 g (0.145 mol) of 3,4-bis (4-nitrophenyl) -2,5-diphenylfuran was dispersed in 500 ml of glacial acetic acid, and 200 ml of concentrated hydrochloric acid in which 383 g (17 mol) of stannous chloride dihydrate was dissolved. After the addition, the mixture was stirred at 100 ° C. for 5 hours. After the reaction, the reaction solution was poured into a large amount of distilled water, and the precipitate was filtered. The precipitate was then sufficiently washed with an aqueous sodium hydroxide solution and distilled water, and then dried. Subsequently, the mixture was recrystallized twice with a toluene-methanol (1: 1) mixed solvent to obtain a white needle crystal. Yield is 39 g (67% yield).

Melting Point: 222-223 ℃

Infrared Absorption Spectrum (KBr): 3375, 3325cm ^-1 (NH)

Elemental Analysis Value: Carbon Hydrogen Nitrogen

Calculated Value (%): 83..56 5.51 6.96

Found (%): 83.85 5.37 6.87

Example 4

Synthesis of 3,4-bis (4-aninophenyl) -2,5-diphenylfuran (hydrogenation method)

Take 1.0 g (2.16 mol) of 3,4-bis (4-nitrophenyl) -2,5-diphenylfuran and 0.24 g of 10% paradium carbon, add 40 ml of dimethylformamide, and stir at 60 ° C. The hydrogen was supplied while the reaction was terminated when the supply of hydrogen was completed after about 10 hours. Activated carbon and dimethylformamide are removed from the reaction solution, and the solid obtained in this way is recrystallized from toluene-methanol to obtain white acicular crystals.

Yield is 0.29 g (33% yield).

Melting Point: 222-223 ℃

Infrared Absorption Spectrum (KBr): 3375, 3325cm ^-1 (NH)

Elemental Analysis Value: Carbon Hydrogen Nitrogen

Calculated Value (%): 83..56 5.51 6.96

Found (%): 83.96 5.28 6.98

Reference Example 1

1,006 g (2.5 mmol) of 3,4-bis (4-aninophenyl) -2,5-diphenylfuran are dissolved in 10 ml of N, N-dimethylacetamide and frozen in a dry ice-acetone bath. 0.508 g (2.5 mmol) of isophthalic acid chloride was added to the solid as it was, and the mixture was changed from a dry ice-acetone bath to an ice bath, stirred at 0 ° C. for 3 hours, and then the viscous polymerization solution was added to 300 ml of methyl alcohol. Obtain amide. Infrared absorption spectrum was observed, respectively the absorption NH, Carney carbonyl absorption to 1650cm ^-1 to 3320cm ^-1 of an amide bond.

Yield 99%

Intrinsic viscosity: 0.70 dl / g (measured at 30 ℃ in concentrated sulfuric acid, 0.5 / dl)

Elemental Analysis Value: Carbon Hydrogen Nitrogen

Calculated Value (%): 81.18 4.54 5.26

Found (%): 80.92 4.31 5.04

Glass transition point (differential scanning calorimetry): 310 ℃

The 10% weight loss temperature by thermogravimetric measurement was 450 ° C. in air and 490 ° C. in nitrogen.

The polyamide according to the present invention is soluble in N, N-dimethylacetamide, N-methyl-2-pyrrolidone, dimethylacetamide, m-cresol, swelling in pyridine, insoluble in acetone chloroform, methyl alcohol.

Claims (2)

The aromatic diamine compound represented by following General formula (i).

Next, a diketone compound of the general formula (III) was prepared by oxidative coupling reaction of paranitrobenzylphenyl ketone of the general formula (II), and a dinitrofuran compound of the general formula (IV) was prepared by dehydration reaction. A method for producing an aromatic diamine compound represented by formula (I), characterized in that for reducing it.