CN107188825A

CN107188825A - A kind of preparation method of 2,4 dinitro benzene hydrazine hydrochloride

Info

Publication number: CN107188825A
Application number: CN201710423829.6A
Authority: CN
Inventors: 李博强
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-06-07
Filing date: 2017-06-07
Publication date: 2017-09-22

Abstract

The invention provides a kind of preparation method of 2,4 dinitro benzene hydrazine hydrochlorides, this method is, for raw material, to react 2,4 dinitro benzene hydrazine hydrochlorides are made at a certain temperature with 2,4 dinitrofluorobenzene, ketazine and water.Add excessive ketazine and water during the course of the reaction so that in reaction system 2,4 DNCB reactions are complete, reaction removes water and ketazine after terminating using vacuum distillation, remaining solid matter is scrubbed, dry after obtain 2,4 dinitro benzene hydrazine hydrochlorides.The inventive method technique is simple, and side reaction is few, and post processing is simple, and product impurity is few, purity is high, and waste discharge is few, and the acetone that by-product is reclaimed during the course of the reaction is the raw material for synthesizing ketazine, be can be recycled, production cost is low.

Description

A kind of preparation method of 2,4 dinitrophenyl hydrazine hydrochloride

Technical field

The invention belongs to chemosynthesis technical field, and in particular to a kind of preparation side of DNPH hydrochloride Method.

Background technology

DNPH hydrochloride is a kind of important fine chemical material, is a variety of medicine of synthesis, agricultural chemicals and dye The intermediate of material.The preparation method of current 2,4 dinitrophenyl hydrazine hydrochloride be typically using 1-CHLORO-2,4-DINITROBENZENE and hydrazine hydrate as Raw material, is made DNPH, then obtain 2,4- dinitros after being acidified with hydrochloric acid with ethanol as solvent heating reflux reaction Hydrazinobenzene hydrochloride salt.The problem of this method is present and have the disadvantage：（1）Side reaction is more, is being heated to reflux producing DNPH During hydrazine hydrate can and ethanol react generation ethyl hydrazine, make the impurity of generation many, post processing is complicated；（2）By 2,4- Dinitrophenylhydrazine filter out after filtrate in contain substantial amounts of hydrazine hydrochloride, hydrazine hydrochloride must add alkali neutralize to reclaim hydrazine hydrate, this mistake Journey can produce a large amount of salt-containing organic wastewaters, and the wastewater treatment difficulty is big, processing cost is high, easily causes environmental pollution；（3）Hydrazine hydrate Expensive, reaction yield is low（Only 80% or so）, production cost height.

The content of the invention

In order to overcome the disadvantages mentioned above that prior art is present, the invention provides a kind of technique is simple, side reaction is few, yield It is high, production cost is low, waste discharge is few, the environmental protection new method for preparing 2,4 dinitrophenyl hydrazine hydrochloride.

The technical solution adopted by the present invention is：Using DNFB, ketazine and water as raw material, in certain temperature 2,4 dinitrophenyl hydrazine hydrochloride is made in lower reaction.Excessive ketazine is added during the course of the reaction（It is both solvent and anti- Answer thing）With water so that the DNFB reaction in reaction system is complete, the acetone produced in course of reaction is filled with rectifying Put back into receipts, reaction removes water and ketazine after terminating using vacuum distillation, remaining solid matter is scrubbed, dry after obtain 2,4 dinitrophenyl hydrazine hydrochloride.

The specific processing step of the inventive method is as follows：DNFB and ketazine are put into reactor, Stirring is opened, 120 DEG C is heated to, water is slowly dropped in reactor, controlling reaction temperature is 100 DEG C~120 DEG C, will The gas that reaction is produced is introduced into rectifying column, acetone is produced at 54 DEG C~58 DEG C of tower top temperature, into the water vapour of rectifying column With ketazine it is condensed after flow back in reactor and continue to participate in reaction；The follow-up continuous insulation reaction of water completion of dropping, works as rectifying column Tower top terminates reaction after being flowed out without acetone, the water and ketazine in reactor is all steamed with negative pressure, consolidating in reactor Body material washs with absolute ethyl alcohol, dry after obtain 2,4 dinitrophenyl hydrazine hydrochloride finished product.

In above-mentioned steps, the mol ratio of DNFB and ketazine is 1: 1.5~2, DNFB Mol ratio with water is 1: 3~5.Its reaction equation is as follows：

Compared with prior art, the beneficial effects of the invention are as follows：The inventive method technique is simple, and side reaction is few, and post processing is simple, Product impurity is few, purity is high（Content is more than 99%）；Course of reaction does not produce salt-containing organic wastewater, and waste discharge is few, almost Produced without " three wastes ", environmental protection；Ketazine is with low cost, be readily synthesized, and reaction yield is high（Existed with ketazine rate of collecting More than 90%）, the acetone that by-product is reclaimed during the course of the reaction is the raw material for synthesizing ketazine, be can be recycled, production cost It is low.

Embodiment

Embodiment 1

1-CHLORO-2,4-DINITROBENZENE 205.6g, ketazine 168g are put into four with stirring, dropping funel, thermometer and rectifying column In mouth flask, stirring is opened, solution is heated to 120 DEG C, water 54ml is slowly dropped in four-hole boiling flask, control reaction Temperature is 100 DEG C~120 DEG C, and after the gas that reaction is produced enters rectifying column, third is produced at 54 DEG C~58 DEG C of column top temperature Ketone, into rectifying column water vapour and ketazine it is condensed after flow back in flask and continue to participate in reaction；Water completion of dropping is follow-up Continuous insulation reaction, terminates reaction after rectifying column receiver flows out without acetone, and the water and ketazine in flask is complete with negative pressure Portion is steamed, the solid matter in flask washs with absolute ethyl alcohol, dry after obtain DNPH hydrochloride 222.7g.

Embodiment 2

1-CHLORO-2,4-DINITROBENZENE 205.6g, ketazine 196g are put into four with stirring, dropping funel, thermometer and rectifying column In mouth flask, stirring is opened, solution is heated to 120 DEG C, water 72ml is slowly dropped in four-hole boiling flask, control reaction Temperature is 100 DEG C~120 DEG C, and after the gas that reaction is produced enters rectifying column, third is produced at 54 DEG C~58 DEG C of column top temperature Ketone, into rectifying column water vapour and ketazine it is condensed after flow back in flask and continue to participate in reaction；Water completion of dropping is follow-up Continuous insulation reaction, terminates reaction after rectifying column receiver flows out without acetone, and the water and ketazine in flask is complete with negative pressure Portion is steamed, the solid matter in flask washs with absolute ethyl alcohol, dry after obtain DNPH hydrochloride 224.5g.

Embodiment 3

1-CHLORO-2,4-DINITROBENZENE 205.6g, ketazine 224g are put into four with stirring, dropping funel, thermometer and rectifying column In mouth flask, stirring is opened, solution is heated to 120 DEG C, water 90ml is slowly dropped in four-hole boiling flask, control reaction Temperature is 100 DEG C~120 DEG C, and after the gas that reaction is produced enters rectifying column, third is produced at 54 DEG C~58 DEG C of column top temperature Ketone, into rectifying column water vapour and ketazine it is condensed after flow back in flask and continue to participate in reaction；Water completion of dropping is follow-up Continuous insulation reaction, terminates reaction after rectifying column receiver flows out without acetone, and the water and ketazine in flask is complete with negative pressure Portion is steamed, the solid matter in flask washs with absolute ethyl alcohol, dry after obtain DNPH hydrochloride 226.1g.

Claims

1. a kind of preparation method of DNPH hydrochloride, it is characterised in that comprise the following steps：By 2,4- dinitros Chlorobenzene and ketazine are put into reactor, are opened stirring, are heated to 120 DEG C, water is slowly dropped in reactor, are controlled Reaction temperature processed is 100 DEG C~120 DEG C, the gas for reacting generation is introduced into rectifying column, at 54 DEG C~58 DEG C of tower top temperature Produce acetone, into rectifying column water vapour and ketazine it is condensed after flow back in reactor and continue to participate in reaction；Water droplet adds Follow-up continuous insulation reaction is finished, terminates reaction after rectifying column tower top flows out without acetone, by the water and ketazine in reactor All steamed with negative pressure, the solid matter in reactor washs with absolute ethyl alcohol, dry after obtain DNPH hydrochloric acid Salt finished product；In above-mentioned steps, the mol ratio of DNFB and ketazine is 1: 1.5~2, DNFB and The mol ratio of water is 1: 3~5.