JPS6127956A - Preparation of 3,4'-diaminodiphenylsulfone - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as an intermediate for a raw material for heat-resistant polyimide and polyamide, or an intermediate for synthesizing agricultural chemical, drug, dye, etc., by reducing catalytically and dechlorinating a dinitrodiphenylsulfonic acid in the presence of a base. CONSTITUTION:2-, Or 4-chloro-3,4'-dinitrodiphenylsulfone shown by the formula (substitution position of chloro group is at 2- or 4-position) is subjected to reduction of nitro group and dechlorinated in the presence of a reducing catalyst (e.g., palladium, or nickel) and a base (e.g., magnesium oxide or pyridine) in a solvent such as isopropyl alcohol, etc. at 0-200 deg.C, preferably at 20-100 deg.C to give the aimed substance. EFFECT:The titled substance is prepared in high purity in high yield without preparing by-products of isomers, causing problems of environmental pollution resulting from waste metal, and requiring complicated purifying process.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a novel method for producing 3,4'-diaminodiphenylsulfone. More specifically, 2- or 4-chloro-3,4'-dinitrodiphenyl sulfone represented by the general formula (in which the chloro group is substituted at the 2 or 4 position) is treated in the presence of a reducing catalyst and a base. , relates to a method for producing 3,4'-diaminodiphenylsulfone, which comprises catalytic reduction and dechlorination.

3.4'-Diaminodiphenylsulfone is useful as a monomer for heat-resistant polymers, an intermediate for agricultural chemicals, dyes, etc., and is an important compound that is particularly used as a raw material for heat-resistant polyimides and polyamides.

Prior Art Conventionally, 3.4'-diaminodiphenylsulfone is 3.4'-diaminodiphenylsulfone.
It is produced by reducing '-dinitrodiphenyl sulfone. That is, a method of catalytic reduction using Raney nickel (Takubo, Pharmaceutical Journal, Competition, 518 (19
42) ), and the reduction method using stannous chloride and hydrochloric acid (B, R. Baker et al., J. Org.

Chem, 15.400 (1950)), etc. are known.

However, in these methods, when producing the raw material 3,4'-dinitrodiphenylsulfone, it is difficult to suppress the by-product of isomers during nitration of 4-nitrodiphenylsulfone. In order to obtain 3,4'-diaminodiphenylsulfone, it is necessary to perform purification by repeating recrystallization several times. Also,
A method for producing 3,4'-dinitrodiphenyl sulfone by oxidizing 3,4'-dinitrodiphenyl sulfide with chromic acid is also known (Takubo, Pharmaceutical Journal, 63,
518 (1942)), it is necessary to use large amounts of chromic acid during oxidation, which poses problems in the treatment of waste heavy metals.
Another disadvantage is that the raw material, 3-nitrothiophenol, is very expensive.

Problems to be Solved by the Invention By the way, diamines used as monomers of heat-resistant polymers, intermediates for agricultural chemicals, dyes, etc. are required to be of extremely high purity in terms of quality. Therefore, as mentioned above, 3,
The method using 4'-dinitrodiphenyl sulfone as an intermediate has problems with by-product isomers and disposal of large amounts of waste heavy metals, so it cannot be said to be an industrially advantageous production method.

Means for Solving the Problems In view of the current state of the production technology for 3,4'-diaminodiphenylsulfone, the present inventors have developed an industrial method for producing 3,4'-diaminodiphenylsulfone that does not involve the by-production of isomers. We have been studying methods for producing diaminodiphenylsulfone.

As a result, oxidation and nitration of 2- or 4-chloro-4'-nitrodiphenyl sulfide using nitric acid and sulfuric acid revealed that 2- or 4-chloro-3,4
'-dinitrodiphenyl sulfone is obtained regioselectively without isomer by-products, and 3. It was discovered that 4'-diaminodiphenylsulfone can be obtained with high purity and high yield, and the present invention was completed. That is, the present invention relates to a new method for producing 3,4'-diaminodiphenylsulfone, in which 2- or 4-chloro-3,
This is a method for producing 3,4'-diaminodiphenylsulfone by subjecting 4'-dinitrodiphenylsulfone to catalytic reduction and dechlorination in an organic solvent in the presence of a reduction catalyst and a base.

The raw material used in the method of the present invention is the bifurcated (2- or 4-chloro, rho-3,4'-dinitrodiphenyl sulfone represented by I+) or a mixture thereof.

As the reduction catalyst used in the method of the present invention, metal catalysts commonly used in catalytic reduction, such as nickel, palladium, platinum, rhodium, ruthenium, cobalt, copper, etc., can be used.

Industrially it is preferred to use palladium catalysts. Although these catalysts can be used as single metals, they are usually supported on the surface of a carrier such as carbon, barium sulfate, barium carbonate, silica gel, or alumina.
Cobalt, copper, etc. are also used as Raney catalysts. The amount of catalyst used is based on the raw material 2- or 4-chloro-3,4'-dinitrodiphenyl sulfone.
It is in the range of 0.01 to 10% by weight as a metal, and usually
When used in the form of metal, it is used in an amount of 2 to 8% by weight, and when supported on a carrier, it is used in a range of 0.1 to 5% by weight.

Bases used in the method of the invention include oxides, hydroxides, carbonates of alkali metals and alkaline earth metals,
Such as bicarbonate, or ammonia or common organic amines. Specifically, calcium oxide, magnesium oxide, lithium hydroxide, sodium hydroxide, potassium hydroxide, barium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, ammonium hydrogen carbonate, ammonia, triethylamine, and triethylamine. Examples include n-butylamine, triethanolamine, pyridine, and the like. Two or more types of these bases may be mixed as necessary. The amount used is 2- or 4- of raw materials.
Usually 0.5 to 3.0 times the mole, preferably 1.0 to chloro-3,4'-dinitrodiphenyl sulfone.
~2.0 times the molar amount is used.

The method of the invention typically uses a solvent. As a solvent,
There is no particular limitation as long as it is inert to the reaction, and if the solvent is miscible with water, water may be added as necessary. Specifically, alcohols such as methanol, ethanol, and inglobil alcohol, ethylene glycol, and alcohols such as fluoroyl,
Ethers such as ether, tetrahydrofuran, dioxane, methylcellosolve, dimethoxyethane, and diglyme, N,N-dimethylformamide, dimethylsulfoxide, and the like can be used. There is no particular restriction on the amount used, and it is sufficient to suspend or dissolve the 2- or 4-chloro-3,4'-dinitrodiphenyl sulfone as the raw material. ~10 times the weight is sufficient.

When carrying out the method of the present invention, (1) a reduction catalyst is added to the 2- or 4-chloro-3,4'-dinitrodiphenylsulfone suspended or dissolved in a solvent, and then hydrogen is introduced under stirring; After reducing the nitro group,
Examples include a method in which a base is added and then dechlorination is carried out, and a method in which a base is added at the same time as the reduction catalyst is added, and then hydrogen is introduced under stirring to carry out reduction of the nitro group and dechlorination at the same time. In either case, the reaction proceeds smoothly and the desired product, 3,4'-diaminodiphenylsulfone, can be produced.

The reaction temperature is not particularly limited, and is generally in the range of 0 to 200°C, particularly preferably 20 to 100°C. The reaction is usually 2~
It will progress in 10 hours. Also, no particular reaction pressure is required;
Normal pressure is sufficient.

As a post-treatment method for the reaction, the catalyst and inorganic salts are removed from the reaction solution obtained by the above method by hot filtration or extraction, and then the solvent is distilled off as necessary to remove the target product.
．． 4'-diaminodiphenylsulfone is precipitated as crystals. Alternatively, the target product can be isolated as a hydrochloride by blowing hydrogen chloride gas into the reaction solution from which the catalyst and inorganic salt have been removed.

Actions and Effects The 3,4'-diaminodiphenylsulfone produced by the method of the present invention has extremely high purity and does not produce by-product isomers unlike conventional methods.

The method of the present invention does not have the environmental pollution problems associated with conventional methods, and the isolated product has high purity, so it does not require complicated purification steps, making it an extremely superior production method from an industrial perspective. be.

Example Hereinafter, the present invention will be explained in detail with reference to Examples.

Example 1 4-chloro-3,4'-dinitrodiphenylsulfone 50P (0,146 mol), inpropyl alcohol 2001111.5% palladium/carbon catalyst (50% hydrated crystal manufactured by Nippon Engelhard) 31 and magnesium oxide 5.951- (0,146 mol) was placed in a closed glass reaction vessel, and hydrogen was absorbed while stirring at 70-75°C.

The reaction was terminated when 21.5// was absorbed, and the catalyst was removed by filtration. When the inpropyl alcohol in the solution was distilled off, crystals were precipitated. After filtering and washing with water, dry
-Diamino diphenyl sulfone was obtained. Yield 3261 (
Yield 9o, 1%) Melting point 129-131°C.

A pure product was obtained by recrystallization from ethanol. Melting point 132-1
33℃.

Elemental analysis value HNS Calculated value (%) 57.99 4.83 11.27
．． 12.89 Analysis value (%) 57.82 4.76
11.18 12.96 Example 2 2-chloro-3,4'-dinitrodiphenyl sulfo 75
0 FC0,146 mol), Et/-ol 30 (IJ,
0.15' of a 5% palladium/carbon catalyst (manufactured by Nippon Engelhard Co., Ltd., 50% hydrated crystal) was placed in a closed glass reaction vessel, and hydrogen was absorbed while stirring at 20 to 30°C.

13.7# Ammonia water with a concentration of 29% at the point where it was absorbed 17,
1 f% (0,292 mol) was added and hydrogen was absorbed while stirring at 60-65°C.

The reaction was terminated when 21.3A was absorbed, and the catalyst was removed by filtration. When the ethanol in the P solution was distilled off, crystals were precipitated. After filtration, washing with water, and drying, 3,4'-diaminodiphenylsulfone was obtained. Yield 32.91 (Yield 90.
9%) melting point 128-131°C.

A pure product was obtained by recrystallization from ethanol. Melting point 132-1
33°C0 Elemental analysis value CH'N S Calculated value (%) 57.99 4.83 11. ．． 27
12.89 Analysis value (%) 57,96 4.92
11.40 12.76 Examples 3 to 6 3,4'-diaminodiphenylsulfone was produced by changing the reaction conditions.

The results are shown in Table-1.

Claims (1)

[Claims] 1) General formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) 2- or 4 represented by (in the formula, the substitution position of the chloro group is the 2 or 4 position) -chloro-3,4'-dinitrodiphenyl sulfone in the presence of a reducing catalyst and a base,
3, characterized by catalytic reduction and dechlorination;
Method for producing 4'-diaminodiphenylsulfone.