WO2002055475A1

WO2002055475A1 - Process for producing 4,6-dinitroresorcinol

Info

Publication number: WO2002055475A1
Application number: PCT/JP2001/000158
Authority: WO
Inventors: Koei Sato; Yasuhito Kato; Jun-Ichiro Tomaru; Masaki Fujimoto
Original assignee: Nippon Kayaku Kabushiki Kaisha
Priority date: 2001-01-12
Filing date: 2001-01-12
Publication date: 2002-07-18

Abstract

A process for producing 4,6-dinitroresorcinol, characterized by reacting a 1,3-dihalo-4,6-dinitrobenzene with a base in an aqueous medium in the presence of a metal catalyst to hydrolyze it and then acidifying. By the process, high-purity 4,6-dinitroresorcinol can be produced at a high percent by volume safely and easily in high yield.

Description

Specification

Production method of 4, 6-dinitroresorcin

The present invention relates to a method for producing 4,6-dinitroresorcin. Background art

4,6-Diaminoresorcin (DAR) obtained by reducing 4,6-dinitroresorcin is a monomer of polyparaphenylene benzobenzoxazole (PBO), a polymer with high heat resistance and high strength. 4,6-Dinitroresorcin is an important raw material. Fibers made of PBO have excellent heat resistance, strength, elastic modulus, and chemical resistance, and are expected as new materials. The following methods are known as conventional methods for producing 4,6-dinitroresorcin. A method in which resorcinol is acetylated, nitrated in a mixed acid of sulfuric acid and nitric acid, and then hydrolyzed (J. Org. Chem. 1 988, 53, 5568). A method in which 1,3-bis (methylcarbonato) benzene obtained by carbonated resorcinol is nitrated in a mixed acid of sulfuric acid and nitric acid and then hydrolyzed (Japanese Patent Application Laid-Open No. 2-136). Each of these methods proposes techniques to prevent unwanted nitration at the 2-position and to prevent the explosive 2,4,6-trinitroresorcin (styphnic acid) by-product. However, the production of styphnic acid is unavoidable, and a step of removing the hydroxyl-protecting group after nitration is necessary, which is industrially problematic. As another method, nitration of resorcinol in concentrated nitric acid in which nitrous oxides are substantially absent in low temperature has been proposed (Japanese Translation of PCT International Publication No. 9-1512790), but the unprotected hydroxyl group is It is unstable to nitric acid, and nitrification in nitric acid has a high risk of oxidation and runaway reaction, and is not industrial.

A process for producing 4,6-dinitroresorcinol by obtaining 3-alkoxy-1,4,6-dinitrophenol from 1,3-dihalo 4,6-dinitrobenzene and hydrolyzing it in sulfuric acid (JP-A-7-316) No. 102) has also been proposed. this The method requires two steps, and the subsequent step, hydrolysis of 3-alkoxy-1,4-dinitrophenol, has a problem that the yield is low and the treatment of the reaction waste liquid is expensive.

It is known that 1,3-dichloro-1,4-dinitrobenzene is hydrolyzed with an aqueous sodium hydroxide solution to directly obtain 4,6-dinitroresorcin. In Japanese Patent Application Laid-Open No. 11-238561, reflux is performed for 4 hours with a 5% aqueous sodium hydroxide solution to obtain a yield of 72%. However, there are many by-products and low volumetric efficiency. Japanese Patent Application Laid-Open No. 7-118811 / 18 discloses that 1,3-dihalo-4,6-dinitrobenzene or 3-halo-4,6-dinitrophenol is converted to alkali metal in a solvent in the presence of an oxidizing agent. Hydrolysis yields 4,6-dinitroresorcin. According to the examples, there is a problem that the volumetric efficiency is not good, or it is necessary to perform an extraction and concentration step with an organic solvent and perform a cumbersome operation of blowing air under reflux.

As described above, conventional methods for producing 4,6-dinitroresorcinol involve explosive by-products, complicated processes, large amounts of Z and reaction waste liquid, and poor capacity efficiency. Has problems. Disclosure of the invention

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, by reacting 1,3-dioctane-4,6-dinitrobenzene with a base in an aqueous solvent in the presence of a metal catalyst, It is possible to produce 4,6-dinitroresorcin (salt) with good volumetric efficiency, low by-products and high yield in an industrially advantageous manner. Also, the 4,6-dinitroresorcin ( By acidifying the reaction solution containing (salt), the desired 4,6-dinitroresorcin can be easily extracted as a crystal, and a highly purified product can be easily isolated by recrystallization from an organic organic solvent. The present invention has been completed. That is, the present invention

(1) 4,6-dinitroresorcinol, characterized in that 1,3-dihalo 4,6-dinitrobenzene is reacted with a base in an aqueous solvent in the presence of a metal catalyst. Is a method for producing the salt,

(2) The method for producing 4,6-dinitroresorcin as described in (1) above, wherein the acid is obtained after hydrolysis.

(3) The method for producing 4,6-dinitroresorcin or a salt thereof according to (1) or (2) above, wherein the metal catalyst is an Ib, IIb, or VIII group metal of the periodic table of elements or a metal compound thereof,

(4) The 4,6-dinitroresorcin or the salt thereof according to the above (1) to (3), wherein the metal catalyst is a copper-based catalyst (preferably copper, copper oxide, copper hydroxide, copper carbonate or a copper salt). Production method,

(5) The method for producing 4,6-dinitroresorcin or a salt thereof according to any one of the above (1) to (4), wherein the base is an alkali metal or an alkaline earth metal or a compound thereof. ,

(6) The method for producing 4,6-dinitroresorcin or a salt thereof according to the above (5), wherein the alkali metal or alkaline earth metal compound is a hydroxide or oxide of an alkali metal or an alkaline earth metal. ,

(7) 4,6-Dinitro according to any one of (1) to (6), wherein the 1,3-dihalo 4,6-dinitrobenzene is 1,3-dichloro-1,4-dinitrobenzene A method for producing resorcinol or a salt thereof,

(8) The method for producing 4,6-dinitroresorcin or a salt thereof according to any one of (1) to (7), wherein the amount of the base used is 2 to 10 equivalents relative to the raw material substrate,

(9) The method for producing 4,6-dinito-mouth resorcinol or a salt thereof according to any one of (1) to (8), wherein the hydrolysis reaction temperature is in a range of 50 to 150 ° C,

(10) The aqueous solvent is water, and the amount used is 5 to 25 g per 1 g of the raw material 1,3-dihalo 4,6-dinitrobenzene (1) to (9) Or the method for producing 4,6-dinitrate resorcin or a salt thereof according to item 1. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the production method of the present invention will be described in detail. Used as a raw material of the present invention 1, Examples of the halogen atom in 3-dioctane-4,6-dinitrobenzene include fluorine, chlorine, bromine and iodine atoms. Examples of 1,3-dihalo 4,6-dinitrobenzene include 1,3-dichloro-1,4,6-dinitrobenzene, 1-chloro-1,3-fluoro-1,4,6-dinitrobenzene, 1-chloro Mouth 3-bromo-4,6-dinitrobenzene, 1-chloro-3-chloride 4,6-dinitrobenzene, 1,3-dibutene 4,6-dinitrobenzene, 1-bromo-3-fluoro-4 , 6-dinitrobenzene, 1-bromo-13-iodo 4,4,6-dinitrobenzene, 1,3-jodo-1,4,6-dinitrobenzene. 1,3-Dichloro-4,6-dinitrobenzene is preferred because of its availability. These may be used alone or in a mixture. 1,3-Dihalo 4,6-dinitrobenzene can be obtained by a known nitration method of 1,3-dihalobenzene (for example, Methoden der Organischer Chemie XZ Vol. 1, 5 13). As the metal catalyst used in the present invention, a metal of Group Ib, Ilb or VIII of the periodic table or a metal compound thereof can be used. Group Ib metals of the periodic table include copper, silver, gold, etc., I lb of the periodic table can include zinc, cadmium, etc., and Group VIII metals of the periodic table include iron, cobalt, nickel, and the like. Examples include ruthenium, rhodium, palladium, and platinum. Examples of the compounds of these metals include metal salts of oxides, hydroxides, organic acids or inorganic acids, for example, octupenic compounds (eg, chlorides, bromides, iodides), and those having 1 to 3 carbon atoms such as acetates. Metal salts of organic acids, and metal salts of inorganic acids such as hydrochloric acid, sulfuric acid and thiocyanic acid. In the present invention, in view of availability and price, a copper-based catalyst, for example, copper powder or a copper compound, more specifically, copper powder, copper oxide such as cuprous oxide or cupric oxide, water Copper hydroxide such as cupric oxide, copper salt of acid (inorganic acid such as carbonic acid, hydrochloric acid or sulfuric acid or organic acid having 1 to 3 carbon atoms), more specifically, copper halide (for example, chloride) Copper (copper), cupric chloride, cuprous bromide, cuprous iodide), copper carbonate such as basic copper carbonate, copper salts of organic acids such as copper acetate, copper sulfate and other copper Compounds, more preferably copper powder, copper oxide, copper hydroxide, copper carbonate, octalogenated Copper or copper sulfate is exemplified. · Nickel compounds such as nickel powder, nickel chloride, nickel bromide, nickel formate, nickel hydroxide, nickel oxide, ruthenium chloride, ruthenium oxide, ruthenium, palladium chloride and paradium Is also a preferred example. These are used alone or in a mixture. The metal catalyst is used in an amount of 0.1 to 20 parts by mass, preferably 0.5 to 10 parts by mass, based on 100 parts by mass of 1,3-dihalo 4,6-dinitrobenzene as the raw material substrate. . The catalyst may be a new catalyst or a recovered and recycled catalyst. Examples of the base used in the present invention include alkali metals, alkaline earth metals or compounds thereof, ammonia, and organic bases. Specific examples include lithium, sodium, and potassium as alkali metals, magnesium, calcium, and barium as alkaline earth metals. Examples of such compounds include oxides, hydroxides, and inorganic weak acids. Salts (for example, carbonates, bicarbonates, phosphates, etc.), and salts with organic acids having 1 to 3 carbon atoms, such as acetic acid, may be mentioned. Examples of the organic base include mono- or polyalkylamines having 1 to 3 carbon atoms such as methylamine, ethylamine, and triethylamine, and pyridines which may be substituted with a lower alkyl group having 1 to 3 carbon atoms such as pyridine and picoline. Is mentioned. Preferred bases include hydroxides and oxides of alkali metals or alkaline earth metals such as sodium hydroxide, potassium hydroxide, calcium hydroxide, calcium oxide, magnesium hydroxide and magnesium oxide, which are easily available at low cost. The base is used in an amount of 2 to 10 equivalents, preferably 3 to 6 equivalents, based on the raw material substrate.

As the solvent used in the present invention, water or a mixture of water and an organic solvent inert to the reaction is used. Examples of organic solvents include aromatic hydrocarbons such as toluene-xylene, secondary and tertiary alcohols such as 2-propanol and tertiary alcohol, and ethers such as dioxane and ethylene daricol dimethyl ether. And aprotic polar solvents such as dimethylformamide, dimethylacetamide, N-methylpyrrolidone, and dimethylsulfoxide. Usually, an aqueous solvent is preferable in consideration of ease of isolation and purification. The amount of the solvent used is not particularly limited, but is preferably small from the viewpoint of volumetric efficiency, usually about 1 to 30 times by mass, preferably about 5 to 25 times by mass with respect to the raw material substrate. Preferably Is about 10 to 25 times by mass.

The reaction can usually be carried out at a temperature in the range of 50 to 150 ° C. However, at a high temperature, decomposition of 4,6-dinitroresorcin tends to occur, and at a low temperature, the reaction is slow. It is preferable to carry out at 130 ° C. The reaction time varies depending on the reaction temperature, the amount of the metal corrosion medium, the base concentration, and the like, but is usually 3 to 15 hours. In the present invention, the reaction does not need to be performed under a special atmosphere such as air bubbling or a nitrogen atmosphere, but can be performed in the presence of ordinary air. However, under certain circumstances, it can be done in those special atmospheres.

As a method for operating the reaction according to the present invention, 1,3-dihalo-4,6-dinitrobenzene is added to water in which a predetermined amount of a base is dissolved or a mixed solvent of water and an organic solvent, and the mixture is stirred and dispersed. And heating to the reaction temperature. The reaction first produces 3-halo 4,6-dinitrophenol as an intermediate, followed by 4,6-dinitroresorcin, forming a salt with the base. The progress of the reaction can be monitored by liquid chromatography. After the reaction, the metal catalyst is removed by filtration, and an acid such as hydrochloric acid is added to make the acid acidic, for example, ρΗ1 to 7, preferably about 3 to 5, to precipitate 4,6-dinitroresorcin. After filtration, washing with water and drying, crystals of 4,6-dinitroresorcin are obtained. If necessary, purify by recrystallization, extraction and removal of by-products, or column chromatography. Purification solvents are acetonitrile, alcohols, esters such as ethyl acetate, ketones such as methylethyl ketone, cellosolves such as methylacetosolve, and dimethylformamide / dimethylacetamide alone or in combination. Can be used. The 4,6-dinitroresorcin thus obtained is subjected to a reduction reaction to obtain DAR. Example

Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these specific examples. In the examples, DCDNB indicates 1,3-dichloro-4,6-dinitrobenzene, and DNR indicates 4,6-dinitroresorcinol. Example 1

13.5 g of 85% by weight potassium hydroxide (0.21 mol, 4.8 equivalents to DCD NB) was dissolved in 130 g of water, and then 12.0 g of 1,3-dichloro-4,6-dinitrobenzene (LC purity) was dissolved. 88.0%, DCDNB 10.56 g, containing 1,3-dichloro-2,4-dinitrobenzene as a component other than DCDNB) and 0.5 g of cupric oxide, followed by stirring and dispersion. After reacting for 12 hours while maintaining the reflux temperature at 103 ° C., the reaction solution was cooled to room temperature, and the catalyst was filtered. The precipitated crystals were collected by filtration, washed with water, and dried to obtain 8.8 g of crude yellow-brown 4,6-dinitroresorcinol (purity: 86.9%, DNR: 7.65 g, yield: 85.8%). By-products were extracted and removed from the crystals in ethyl acetate to obtain 6.9 g of 4,6-dinitroresorcinol having an LC purity of 99.9%. Example 2

Dissolve 13.5 g of 85% by mass hydroxide hydroxide in 130 g of water, then 12.0 g (LC ^ 88%) of 1,3-dichloro-4,6-dinitrobenzene, 0.5 g of cupric oxide as a metal catalyst and chloride Ruthenium (III) hydrate (0.02 g) was added and dispersed by stirring. After reacting for 12 hours while maintaining the reflux temperature at 103 ° C., the reaction solution was cooled to room temperature, the catalyst was filtered, and hydrochloric acid was added to the filtrate to precipitate crystals. The crystals were filtered, washed with water and dried to obtain 9.1 g of crude yellow-brown 4,6-dinitroresorcin (LC purity 87.7%, DNR 7.98 g, yield 89.5%). The crystals were recrystallized from acetonitrile to obtain 7.2 g of 4,6-dinitroresorcinol having a purity of 99.7%. Example 3

Dissolve 8 g (0.12 mo 1, 5.0 equivalents based on DCDNB) of 85 mass% hydroxide hydroxide in 130 g of water and then add 1,3-dichloro-1,4,6-dinitrobenzene 5.5 g g ((88% purity)) and 0.1 g of basic copper carbonate as a metal catalyst were added and dispersed by stirring.The mixture was reacted at reflux temperature of 103 ° C for 12 hours, cooled to room temperature, filtered to remove the catalyst, and added to the filtrate. Hydrochloric acid was added to precipitate crystals, which were filtered, washed with water, Drying yielded 3.8 g of crude yellow-brown 4,6-dinitroresorcin (3.34 g of 88% pure DNR, 81.7% yield). Crystallization gave 2.8 g of 4,6-dinitroresorcinol having a purity of 99.8%.

13.5 g of 85% by weight potassium hydroxide was dissolved in 130 g of water, and then 12.0 g of 1,3-dichloro-1,4,6-dinitrobenzene (B: 88% purity) was added and dispersed by stirring. The reaction was carried out for 12 hours while keeping at ° C. Post-treatment was carried out in the same manner as in Example 1 to obtain 7.1 g of crude brown 4,6-dinitroresorcinol (LC purity: 70.5%, DNR: 4.97 g, yield: 55.7%). The crystals were recrystallized from acetonitrile to obtain 4.3 g of 4,6-dinitroresorcinol having a purity of 99.7%. Industrial applicability

In the production method of the present invention, a metal catalyst is used to convert 4,6-dinitroresorcin from 1,3-dihalo 4,6-dinitrobenzene to a safe and simple operation at a high volume ratio and a high yield. Can be obtained with high purity.

Claims

The scope of the claims

1. A process for producing 4,6-dinitroresorcinol or a salt thereof, comprising reacting 1,3-dihalo 4,6-dinitrobenzene with a base in an aqueous solvent in the presence of a metal catalyst and hydrolyzing it. .

2. The method for producing 4,6-dinitroresorcin according to claim 1, which is made acidic after hydrolysis.

3. The method for producing 4,6-dinitroresorcin or a salt thereof according to claim 1, wherein the metal catalyst is an Ib, Ilb, or VIII group metal of the periodic table or a metal compound thereof.

4. The method for producing 4,6-dinitroresorcin or a salt thereof according to claim 1, wherein the metal catalyst is a copper-based catalyst.

5. The method for producing 4,6-dinitroresorcin or a salt thereof according to any one of claims 1 to 4, wherein the base is an alkali metal or an alkaline earth metal or a compound thereof. . ,

6. The 4,6-dinitroresorcin or a salt thereof according to claim 5, wherein the alkali metal or alkaline earth metal compound is a hydroxide or oxide of an alkali metal or alkaline earth metal. Manufacturing method.

7.1. 4, 6-Dihalo-4, 6-dinitrobenzene is 1,3-dichloro-4, 6-dinitrobenzene, 4, 6- described in any one of claims 1 to 4 A method for producing dinitroresorcin or a salt thereof.

8. The method for producing 4,6-dinitroresorcin according to any one of claims 1 to 4, wherein the amount of the base used is 2 to 10 equivalents relative to the raw material substrate.

9. The process for producing 4,6-dinitrate resorcinol or a salt thereof according to any one of claims 1 to 4, wherein the hydrolysis reaction temperature is in the range of 50 to 150 ° C. Construction method.

10. The aqueous solvent is water, and the used amount thereof is 5 to 25 g per 1 g of 1,3-dihalo 4,6-dinitrobenzene of the raw material.

4. The method for producing 4,6-dinitroresorcin or a salt thereof according to any one of paragraphs 4.