CN100595335C - 1,5-dinaphthylamine electrochemical synthesis method - Google Patents

Abstract

Provided is an electrochemical synthetic method of 1,5-diaminonaphthalene, which includes four steps that firstly the electrochemical synthetic of diaminonaphthalene is performed in an electrolytic cell which contains a cathode chamber and an anode chamber which are separated by a cation-exchange membrane which is taken as a permeable membrane, copper sheets and a calomel electrode which are installed in the cathode chamber are respectively taken as working electrodes and a saturated reference electrode, and ruthenium-plated iron screens which are arranged inside the cathode chamber are takenas auxiliary electrodes. Secondly catholyte is mixed solution of solvent N, N-dimethyl formamide, sulfuric acid solution supporting electrolyte and substrate 1, 5-diaminonaphthalene, and anolyte is sulfuric acid solution of which the volume is equal to the volume of the catholyte. Thirdly electrolyzation is performed at room temperature and under the condition that the working electrodes are driven by a certain constant potential relative to the saturated reference electrode. Fourthly after the electrolyzation is finished, the electrolytic solution is post-processed to obtain the product of 1,5-diaminonaphthalene. The method has the advantages of simple requirement, easy preparation of the electrodes, ready availability of raw material, greening synthetic process, normal reaction temperature, small energy consumption, high yield and suitability to industrial production.

Description

1, the electrochemical method for synthesizing of 5-diaminonaphthalene

Technical field

The present invention relates to a kind ofly 1, the electrochemical method for synthesizing of 5-diaminonaphthalene belongs to technical field of electrochemistry.

Background technology

1, the 5-diaminonaphthalene, English name: 1,5-diaminonaphthalene or1,5-naphthylenediamine, molecular formula C ₁₀H ₁₀N ₂, be a kind of colourless crystallization, 190 ℃ of fusing points can be dissolved in N, and dinethylformamide, ethanol, EC slightly are dissolved in hot water, can distil, and with the passing of time turn brown, meet liquor ferri trichloridi and are livid purple look, poisonous, and when using in a large number, the staff need wear vest.1,5-diaminonaphthalene purposes is very extensive, main as making 1, the 5-naphthalene diisocyanate, be one of raw material of synthetic senior polyurethane elastomer, be usually used in the raw material and the intermediate of multiple fine chemical products such as organic synthesis, pigment, dyestuff, medicine, agricultural chemicals, rubber ingredients, resin, sensitive materials.

Though 1, the 5-diaminonaphthalene is unusual useful as intermediates, does not find very satisfied preparation technology in actual industrial production so far yet, existing preparation technology is enumerated as follows:

1, U.S. Patent No. 6538158 (2003) is a raw material with the naphthalene, by bromination preparation 1, and the 5-dibromine naphthalene, ammonia is separated preparation 1,5-diaminonaphthalene again.The shortcoming of this technology is to have in a large number 1, and the 4-dibromine naphthalene generates, the separation purification difficult of product.

2, U.S. Patent No. 0143137 (2004) is a raw material with the Ortho Nitro Toluene, by with third rare nitrile base catalysis addition, acid catalysis closed loop, shortening preparation 1,5-diaminonaphthalene.The shortcoming of this technology is the synthesis technique complexity.

3, U.S. Patent No. 49737584 (1990) is with 1, and the 5-naphthalenediol is a raw material, separates preparation 1,5-diaminonaphthalene through ammonia.The shortcoming of this technology be temperature of reaction height, time long, catalyst levels is big, severe reaction conditions.

4, U.S. Patent No. 4026944 (1977) utilizes naphthalene to be raw material, and by nitrated preparation 1, the 5-dinitronaphthalene restores preparation 1, the 5-diaminonaphthalene.The shortcoming of this technology is in the nitrated preparation 1 of naphthalene, during the 5-dinitronaphthalene, has in a large number 1, and the 8-dinitronaphthalene generates, the separation purification difficult of product.

Existing 1, in the synthesis technique of 5-diaminonaphthalene, or separation purification difficult, or synthesis technique complexity, or the temperature of reaction height, the time is long, catalyst levels is big, and severe reaction conditions maybe can produce a large amount of wastes, so for the green synthesis method in modern times, existing synthesis technique has had no advantage and can say.

At present, do not see as yet both at home and abroad with electrochemical method and synthesize 1, the report of 5-diaminonaphthalene.

Summary of the invention

The objective of the invention is to release a kind of 1, the electrochemical method for synthesizing of 5-diaminonaphthalene.This method has that equipment requirements is simple, electrode is easy to prepare, raw material is easy to get, the building-up process greenization, reaction is carried out at normal temperatures, energy consumption is little, yield is high and the advantage of suitable suitability for industrialized production.

Technical scheme of the present invention is that described synthetic method comprises that equipment is prepared, preparation, electrolytic process and four steps of aftertreatment of electrolytic solution: need contain the cathode and anode chamber, implement in therebetween by the electrolyzer of separating as the cationic exchange membrane of permeable membrane, by copper sheet and saturated calomel electrode are installed in the negative electrode chamber, make work electrode and reference electrode respectively, the iron net of plating ruthenium is installed in the positive electrode chamber, makes supporting electrode; Catholyte is solvent N, dinethylformamide, supporting electrolyte dilution heat of sulfuric acid and substrate 1, and 5-dinitronaphthalene mixing solutions, anolyte are the dilution heat of sulfuric acid that volume equals the catholyte volume; Electrolytic process at room temperature carries out under the driving that with respect to reference electrode is some constant potential with working electrode; After electrolysis finished, aftertreatment electrolytic solution got product 1, the 5-diaminonaphthalene.

Now describe technical scheme of the present invention in detail.

A kind of 1, the electrochemical method for synthesizing of 5-diaminonaphthalene is characterized in that, concrete steps:

The first step equipment is prepared

Described synthetic method need contain the cathode and anode chamber, implement in therebetween by the electrolyzer of separating as the cationic exchange membrane of permeable membrane, electrolyzer is made up of the cathode and anode chamber, separate with cationic exchange membrane between two Room, make work electrode and reference electrode respectively with copper sheet and saturated calomel electrode, working electrode and reference electrode insert cathode compartment, iron net with the plating ruthenium is made supporting electrode, and supporting electrode inserts the anolyte compartment;

The preparation of the second one-step electrolysis liquid

Electrolytic solution comprises catholyte and anolyte, and catholyte is by 1 of substrate 0.0218～0.0545g, 5-dinitronaphthalene, the N of solvent 16.67ml, 1.5～3.5mol.L of dinethylformamide and supporting electrolyte 3.33ml ^-1Sulphuric acid soln mix, anolyte is 1.5～3.5mol.L that volume equals the catholyte volume ^-1Sulphuric acid soln, described catholyte and anolyte inject described cathode compartment and anolyte compartment respectively;

The 3rd one-step electrolysis process

Electrolytic process at room temperature and working electrode with respect to reference electrode be-0.5～-carry out under the driving of certain constant potential between the 1.0V, the energising amount is every mol 1,5-dinitronaphthalene 4.5～9F;

The 4th step aftertreatment

Add the neutralization of solid sodium hydroxide to the catholyte of handling through the 3rd step, add the solid sodium bicarbonate again to saturated, the pH value that makes catholyte is between 8～9, revolve and steam the N that removes in the catholyte, dinethylformamide and water, to the complete evaporate to dryness of liquid quilt, divide the product that obtains to evaporate to dryness for four times to add methylene chloride, the add-on of methylene dichloride is respectively 40,30,20,10ml merges four dichloromethane solutions that are dissolved with product, the water extracting and washing, remove inorganic salt residual in the methylene dichloride, add anhydrous sal epsom to extraction liquid, remove the moisture in the extraction liquid, remove by filter sal epsom, vacuum rotary steam is removed part methylene chloride, get product 1,5-diaminonaphthalene solution, productive rate are 36.24%～75.45%.

Compare with its background technology, the invention has the advantages that:

1. reaction is at room temperature carried out, and the reaction times is short, and energy consumption is low.

2. make the work electrode with copper, be easy to processing, low price.

3. aftertreatment is fairly simple, has saved the extraction step in the normal experiment.

Embodiment

Now further specify the technical scheme of invention by embodiment.All embodiment operate according to the concrete steps of described synthetic method fully.Each step of embodiment is only enumerated crucial technical data.

Embodiment one

In second step, catholyte is by 0.0436g 1,5-dinitronaphthalene, 16.67ml N, dinethylformamide and 3.33ml1.5mol.L ^-1Sulphuric acid soln mix, anolyte is 20ml1.5mol.L ^-1Sulphuric acid soln;

In the 3rd step, constant potential is-0.5V that the energising amount is every mol 1,5-dinitronaphthalene 6F;

In the 4th step, productive rate is 55.38%.

Embodiment two

In second step, catholyte is by 0.0436g 1,5-dinitronaphthalene, 16.67ml N, dinethylformamide and 3.33ml1.5mol.L ^-1Sulphuric acid soln mix, anolyte is 20ml1.5mol.L ^-1Sulphuric acid soln;

In the 3rd step, constant potential is-0.8V that the energising amount is every mol 1,5-dinitronaphthalene 6F;

In the 4th step, productive rate is 63.04%.

Embodiment three

In second step, catholyte is by 0.0436g 1,5-dinitronaphthalene, 16.67ml N, dinethylformamide and 3.33ml 1.5mol.L ^-1Sulphuric acid soln mix, anolyte is 20ml 1.5mol.L ^-1Sulphuric acid soln;

In the 3rd step, constant potential is-1.0V that the energising amount is every mol 1,5-dinitronaphthalene 6F;

In the 4th step, productive rate is 49.36%.

Embodiment four

In second step, catholyte is by 0.0218g 1,5-dinitronaphthalene, 16.67ml N, dinethylformamide and 3.33ml 1.5mol.L ^-1Sulphuric acid soln mix, anolyte is 20ml 1.5mol.L ^-1Sulphuric acid soln;

In the 3rd step, constant potential is-0.8V that the energising amount is every mol 1,5-dinitronaphthalene 6F;

In the 4th step, productive rate is 38.12%.

Embodiment five

In second step, catholyte is by 0.0545g1,5-dinitronaphthalene, 16.67ml N, dinethylformamide and 3.33ml 1.5mol.L ^-1Sulphuric acid soln mix, anolyte is 20ml 1.5mol.L ^-1Sulphuric acid soln;

In the 3rd step, constant potential is-0.8V that the energising amount is every mo l 1,5-dinitronaphthalene 6F;

In the 4th step, productive rate is 36.24%.

Embodiment six

In second step, catholyte is by 0.0436g 1,5-dinitronaphthalene, 16.67ml N, dinethylformamide and 3.33ml 1.5mol.L ^-1Sulphuric acid soln mix, anolyte is 20ml1.5mol.L ^-1Sulphuric acid soln;

In the 3rd step, constant potential is-0.8V that the energising amount is every mol 1,5-dinitronaphthalene 9F; In the 4th step, productive rate is 42.58%.

Embodiment seven

In second step, catholyte is by 0.0436g 1,5-dinitronaphthalene, 16.67ml N, dinethylformamide and 3.33ml 1.5mol.L ^-1Sulphuric acid soln mix, anolyte is 20ml 1.5mol.L ^-1Sulphuric acid soln;

In the 3rd step, constant potential is-0.8V that the energising amount is every mol 1,5-dinitronaphthalene 4.5F;

In the 4th step, productive rate is 55.11%.

Embodiment eight

In second step, catholyte is by 0.0436g 1,5-dinitronaphthalene, 16.67ml N, dinethylformamide and 3.33ml 2.5mol.L ^-1Sulphuric acid soln mix, anolyte is 20ml2.5mol.L ^-1Sulphuric acid soln;

In the 3rd step, constant potential is-0.8V that the energising amount is every mol 1,5-dinitronaphthalene 6F;

In the 4th step, productive rate is 75.45%.

Embodiment nine

In second step, catholyte is by 0.0436g 1,5-dinitronaphthalene, 16.67ml N, dinethylformamide and 3.33ml 3.5mol.L ^-1Sulphuric acid soln mix, anolyte is 20ml3.5mol.L ^-1Sulphuric acid soln;

In the 3rd step, constant potential is-0.8V that the energising amount is every mol 1,5-dinitronaphthalene 6F;

In the 4th step, productive rate is 47.77%.

Claims (1)

1, a kind of 1, the electrochemical method for synthesizing of 5-diaminonaphthalene is characterized in that, concrete steps:

The first step equipment is prepared

Described synthetic method need contain the cathode and anode chamber, implement in therebetween by the electrolyzer of separating as the cationic exchange membrane of permeable membrane, electrolyzer is made up of the cathode and anode chamber, separate with cationic exchange membrane between two Room, make work electrode and reference electrode respectively with copper sheet and saturated calomel electrode, working electrode and reference electrode insert cathode compartment, iron net with the plating nail is made supporting electrode, and supporting electrode inserts the anolyte compartment;

The preparation of the second one-step electrolysis liquid

Electrolytic solution comprises catholyte and anolyte, and catholyte is by 1 of substrate 0.0218～0.0545g, 5-dinitronaphthalene, the N of solvent 16.67ml, 1.5～3.5mol.L of dinethylformamide and supporting electrolyte 3.33ml ^-1Sulphuric acid soln mix, anolyte is 1.5～3.5mol.L that volume equals the catholyte volume ^-1Sulphuric acid soln, described catholyte and anolyte inject described cathode compartment and anolyte compartment respectively;

The 3rd one-step electrolysis process

Electrolytic process at room temperature and working electrode with respect to reference electrode be-0.5～-carry out under the driving of certain constant potential between the 1.0V, the energising amount is every mol 1,5-dinitronaphthalene 4.5～9F;

The 4th step aftertreatment

Add the neutralization of solid sodium hydroxide to the catholyte of handling through the 3rd step, add the solid sodium bicarbonate again to saturated, the pH value that makes catholyte is between 8～9, revolve and steam the N that removes in the catholyte, dinethylformamide and water, to the complete evaporate to dryness of liquid quilt, divide the product that obtains to evaporate to dryness for four times to add methylene chloride, the add-on of methylene dichloride is respectively 40,30,20,10ml merges four dichloromethane solutions that are dissolved with product, the water extracting and washing, remove inorganic salt residual in the methylene dichloride, add anhydrous sal epsom to extraction liquid, remove the moisture in the extraction liquid, remove by filter sal epsom, vacuum rotary steam is removed part methylene chloride, get product 1,5-diaminonaphthalene solution, productive rate are 36.24%～75.45%.