CN106565534A - Synthesis method for aromatic hydrazine sulfate - Google Patents
Synthesis method for aromatic hydrazine sulfate Download PDFInfo
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- CN106565534A CN106565534A CN201610965101.1A CN201610965101A CN106565534A CN 106565534 A CN106565534 A CN 106565534A CN 201610965101 A CN201610965101 A CN 201610965101A CN 106565534 A CN106565534 A CN 106565534A
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- hydrazine sulfate
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- aryl hydrazine
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C241/00—Preparation of compounds containing chains of nitrogen atoms singly-bound to each other, e.g. hydrazines, triazanes
- C07C241/02—Preparation of hydrazines
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C245/00—Compounds containing chains of at least two nitrogen atoms with at least one nitrogen-to-nitrogen multiple bond
- C07C245/20—Diazonium compounds
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Abstract
The invention discloses a synthesis method for aromatic hydrazine sulfate. The synthesis method includes the steps that firstly, aromatic amine is added in sulfuric acid with the mass fraction ranging from 15% to 65%, the temperature is lowered to -5-15 DEG C, a diazotization reagent is dropwise added in the reaction liquid, and diazonium salt is obtained after reaction; secondly, a reducing agent is prepared into a solution, a reducing solution is obtained, the diazonium salt obtained in the first step is dropwise added in the reducing solution, heating reduction is conducted after drop-by-drop addition is completed, and reducing material liquid is obtained through filtration; and thirdly, the reducing material liquid obtained in the second step is heated, dilute sulphuric acid is dropwise added in the reducing material liquid to conduct the acidolysis reaction, the temperature is lowered after the reaction is finished, the aromatic hydrazine sulfate is separated out, a filter cake and filtrate are obtained through filtration, the filter cake is washed with dilute sulphuric acid, and an aromatic hydrazine sulfate product is obtained, and sodium sulfate salt is recycled after the filtrate is preprocessed. Compared with a traditional process, the obtained aromatic hydrazine sulfate is high in yield and purity, the purity reaches 97% or above, the yield is higher than 91%, salt in the wastewater obtained through the reaction is the simplex sodium sulfate salt, and the recycling value is high.
Description
Technical field
The present invention relates to organic compound synthesis field, a kind of specifically conventional aryl hydrazine sulphuric acid of medicine intermediate
The synthetic method of salt.
Background technology
Aryl hydrazine as a kind of important industrial chemicals and intermediate, in organic synthesiss and essences such as medicine, pesticide and dyestuffs
Thin chemical field plays very important effect, especially recently as heterocyclic compound further investigation and application it is continuous
Expand, aryl hydrazine is more and more obvious in the effect of fine chemistry industry and organic synthesis field.
At present, the synthetic method of aryl hydrazine mainly carries out diazo-reaction by raw material of aromatic amine under the conditions of hydrochloric acid,
The diazol for obtaining is reduced with sodium sulfite or sodium sulfite, and reducing solution dilute hydrochloric acid carries out, after acidolysis reaction, obtaining
To fragrant hydrazinobenzene hydrochloride salt.The hydrochlorate liquid caustic soda that the method is obtained is reacted to pH and obtains to chlorophenyl hydrazine product for 10 or so, so
Aryl hydrazine is dissolved in sulphuric acid to prepare aryl hydrazine sulfate afterwards, contains substantial amounts of mixed salt, promote in the waste water that the technique is produced
Solid waste increases, and the recycling value of subsequent treatment is very low.
A kind of preparation method (CN104151188A) of 2- chlorophenyl hydrazines sulfate is using stannous chloride-hydrochloric acid as reducing agent
Sodium sulfite and sodium sulfite is replaced to carry out reduction reaction, the method reducing property is good, purity 99%, but yield only has
42%, and using the high cost of stannous chloride, in the waste water for obtaining, existing sodium sulfate has sodium chloride salt, and recovery value is low,
Can only be used as fixed-end forces.
A kind of synthetic method of phenylhydrazine of the disclosure of the invention of Application No. 201510061685.5, with aniline as raw material, adopts
It is acidified with sulphuric acid, ammonium nilrite does diazo reagent, synthesized phenylhydrazine, and in solving the problems, such as waste water, Inorganic Salts are more.But,
There is problems with：(1) acidulant is done using sulphuric acid, the acidity of required sulphuric acid is higher, of a relatively high (2) the diazonium process temperature of cost
Spend for -5～-15 DEG C, temperature is relatively low, control more difficult, high cost；(3) phenylhydrazine is obtained by extract and separate, operation is complicated,
Capital construction cost and operating cost are all high；(4) pH is adjusted using ammonia in extraction process, ammonia is volatile, is also easy to produce air pollution；
(5) diazo reagent is done using ammonium nilrite, ammonium nilrite easily decomposes, explosive, it is dangerous higher；(6) solid reductant is adopted,
It is easily caused local response acutely, the problem that reaction efficiency is reduced；(7) phenylhydrazine yield is low, and about 80% or so.
The content of the invention
To overcome the drawbacks described above of prior art, the invention provides a kind of synthetic method of aryl hydrazine sulfate, the work
Skill is simple, and single sodium sulfate salt, recoverable are only produced in low cost, and waste water.
A kind of synthetic method of aryl hydrazine sulfate, it is characterised in that comprise the following steps：
Step one：Aromatic amine is added in the sulphuric acid that mass fraction is 15%～65%, -5～15 DEG C are cooled to；Toward instead
Deca diazo reagent in liquid, reaction is answered to obtain diazol；
Step 2：By reducing agent wiring solution-forming, reducing solution is obtained, the diazol that Deca step one is obtained toward reducing solution,
Completion of dropping post-heating is reduced, and is filtered and must be reduced feed liquid；
Step 3：The reduction feed liquid that heating stepses two are obtained, and Deca dilute sulfuric acid carries out acidolysis reaction, reaction knot thereto
Shu Jiangwen separates out aryl hydrazine sulfate, is filtrated to get filter cake and filtrate, and filter cake is washed with dilute sulfuric acid, obtains aryl hydrazine sulfate
Product；Filtrate reclaims sodium sulfate salt after pretreatment.
Preferably, the aromatic amine of step one is halo aniline or aniline, further preferably, halo aniline can be parachloroanilinum
Or para-bromoaniline.
In step one, aromatic amine carries out diazotising, and adoptable diazo reagent is sodium nitrite, ammonium nilrite, nitrosyl
Sulphuric acid etc..Preferably, the present invention adopts sodium nitrite or nitrosyl sulfuric acid to do diazo reagent.When diazo reagent is nitrous acid
During sodium, sulphuric acid mass fraction is 40%～65%；When diazo reagent be nitrosyl sulfuric acid when, sulphuric acid mass fraction be 15%～
40%.
Further, in step one, the ratio of the amount of the material of aromatic amine and diazo reagent is 1:1～1.05.
Whether the reaction end of step one is determined can have nitrosyl sulfur with starch potassium iodide paper detection reaction system
Whether acid or sodium nitrite, observation reagent paper become blue, and reagent paper becomes blue explanation aromatic amine reaction and finishes, and reaction temperature is preferably controlled in -5
～5 DEG C.
In step 2 reducing agent can be sulphite, bisulfites, one or more in pyrosulfate, preferably
One or more in sodium sulfite, sodium sulfite or sodium pyrosulfate.Aromatic amine is 1 with the ratio of the amount of the material of reducing agent:2
～3.5.
Preferably, making reduction anti-toward Deca sodium hydroxide solution while Deca diazol in reducing solution in step 2
Reactant liquor pH is kept to be 4-9 during answering.
Preferably, course of reaction is carried out in heat-insulation system in step 2, controlling reaction temperature is below 70 DEG C.This is anti-
Should be exothermic reaction, feed liquid is heated by the reaction heat discharged in course of reaction, but temperature more than 70 DEG C when, the pair of reduction reaction
Products collection efficiency is raised rapidly.
Compared to traditional handicraft, the invention has advantages below：
1) salt in the waste water that reaction is obtained is single sodium sulfate salt, recycles value high.
2) the method obtains high to aryl hydrazine sulfate yield and purity, and up to more than 97%, yield is higher than 91% to purity.
3) the aryl hydrazine sulfate that the method is obtained is compared conventional fragrant hydrazine hydrochloride and is more difficult to be oxidized, and stability is high,
Application effect is more preferable.
Specific embodiment
Below by embodiment, the present invention will be further described：
Embodiment 1
Weigh parachloroanilinum 12.7g to be added in the sulphuric acid that 60g mass fractions are 11%, ice bath is cooled to 5 DEG C, keeping should
Temperature slowly Deca content be 28% nitrosylsulfuric acid (hereinafter referred to as liquid sub-) 47g, react 2h, surveyed with starch potassium iodide paper
Determine parachloroanilinum reaction to finish, obtain diazol.
30g sodium sulfite is weighed, add water the sodium sulfite solution for being made into 20%, while toward Deca above-mentioned steps in the solution
The diazol and mass fraction of generation are 30% liquid caustic soda, and it is 6-7 that Deca process keeps pH, is heated up after diazol completion of dropping
To 70 DEG C, 13h is incubated, reduction reaction terminates, is filtered, filtrate is obtained for reduzate.
The reduzate for obtaining is heated to 80 DEG C, is slowly added dropwise to the sulphuric acid that mass fraction is 20%, keeps pH to be 2, instead
1h is answered, is produced without sulfur dioxide with pH detection paper, acidolysis reaction is finished.Cooling, is filtrated to get and chlorophenyl hydrazine sulfate is slightly produced
Product and filtrate, the crude product for the obtaining dilute sulfuric acid of 60g mass fractions 20% are washed and obtain, to chlorophenyl hydrazine sulfate, obtaining
Product purity 98%, yield 92%.
Salt content 23% in the filtrate for obtaining, filtrate can obtain the sodium sulfate salt of purity 99% through processing.
Obtain to chlorophenyl hydrazine sulfate as Material synthesis downstream product 1- (4- chlorphenyls) -3- pyrazoles alcohol, obtain 1-
(4- chlorphenyls) -3- pyrazoles alcohol yield is 75%, and purity 98% can be used as the intermediate of synthesizing pyrazole kresoxim-methyl.
Embodiment 2
Weigh parachloroanilinum 12.7g to be added in the sulphuric acid that 60g mass fractions are 11%, ice bath is cooled to 5 DEG C, keeping should
Temperature slowly Deca content be 40% liquid Asia 30g, react 2h, with starch potassium iodide paper determine parachloroanilinum reaction finish,
Obtain diazol.
28g sodium sulfitees are weighed, add water the sodium sulfite solution for being made into 20%, with the liquid caustic soda that mass fraction is 30%
PH is neutralized to for 6-7, while toward the diazol of Deca above-mentioned steps generation in the solution and liquid caustic soda that mass fraction is 30%,
It is 6-7 that Deca process keeps pH, and 70 DEG C are warming up to after diazol completion of dropping, is incubated 3h, and reduction reaction terminates, and filters, obtains
Filtrate is reduzate.
The reduzate for obtaining is heated to 80 DEG C, is slowly added dropwise to the sulphuric acid that mass fraction is 20%, keeps pH to be 2, instead
1h is answered, is produced without sulfur dioxide with pH detection paper, acidolysis reaction is finished.Cooling, is filtrated to get and chlorophenyl hydrazine sulfate is slightly produced
Product and filtrate, the crude product for the obtaining dilute sulfuric acid of 60g mass fractions 20% are washed and obtain, to chlorophenyl hydrazine sulfate, obtaining
Product purity 98%, yield 91%.
Salt content 21% in the filtrate for obtaining, filtrate can obtain the sodium sulfate salt of purity 99% through processing.
Embodiment 3
Weigh parachloroanilinum 12.7g to be added in the sulphuric acid that 60g mass fractions are 50%, ice bath is cooled to 5 DEG C, keeping should
Temperature slowly Deca content be 28% sodium nitrite solution, react 2h, with starch potassium iodide paper determine parachloroanilinum reaction
Finish, obtain diazol.
30g sodium sulfite is weighed, add water the sodium sulfite solution for being made into 20%, while toward Deca above-mentioned steps in the solution
The diazol and mass fraction of generation are 30% liquid caustic soda, and it is 6-7 that Deca process keeps pH, is heated up after diazol completion of dropping
To 70 DEG C, 3h is incubated, reduction reaction terminates, is filtered, filtrate is obtained for reduzate.
The reduzate for obtaining is heated to 80 DEG C, is slowly added dropwise to the sulphuric acid that mass fraction is 20%, keeps pH to be 2, instead
1h is answered, is produced without sulfur dioxide with pH detection paper, acidolysis reaction is finished.Cooling, is filtrated to get and chlorophenyl hydrazine sulfate is slightly produced
Product and filtrate, the crude product for the obtaining dilute sulfuric acid of 60g mass fractions 20% are washed and obtain, to chlorophenyl hydrazine sulfate, obtaining
Product purity 98%, yield 91%.
Salt content 18% in the filtrate for obtaining, filtrate can obtain the sodium sulfate salt of purity 99% through processing.
Comparative example 4-9
Test as a comparison, sodium sulfite and two kinds of sodium sulfite, sodium sulfite and liquid caustic soda are selected with synthesis buffering
System can effectively control pH, obtain the generation of by-product is controlled in reduction process, obtain yield and purity is more preferable
Product, secondly reaction temperature is very big to the technogenic influence, especially diazonium temperature and reduction temperature, when diazotising temperature is higher than
15 DEG C, substantial amounts of diazol decomposes, and the product yield and purity for obtaining is relatively low, and reduction temperature is too high to occur excessive pair instead
Should, affect product purity and yield.
Comparative example 10-12
Test as a comparison, from inferior ammonium nitrate as diazo reagent, because inferior ammonium nitrate is in temperature under acid condition
It is extremely easy in decomposition when higher so that product yield is substantially low, and compared to aniline, is synthesized to chlorophenyl hydrazine sulfur from parachloroanilinum
Hydrochlorate is obtained in that higher yield.
Claims (9)
1. a kind of synthetic method of aryl hydrazine sulfate, it is characterised in that comprise the following steps：
Step one：Aromatic amine is added in the sulphuric acid that mass fraction is 15%～65%, -5～15 DEG C are cooled to；Toward reactant liquor
Middle Deca diazo reagent, reaction obtain diazol；
Step 2：By reducing agent wiring solution-forming, reducing solution is obtained, the diazol that Deca step one is obtained toward reducing solution, Deca
Post-heating reduction is finished, is filtered and must be reduced feed liquid；
Step 3：The reduction feed liquid that heating stepses two are obtained, and Deca dilute sulfuric acid carries out acidolysis reaction thereto, reaction terminates drop
Temperature separates out aryl hydrazine sulfate, is filtrated to get filter cake and filtrate, and filter cake is washed with dilute sulfuric acid, obtains aryl hydrazine sulfate product
Product；Filtrate reclaims sodium sulfate salt after pretreatment.
2. the synthetic method of aryl hydrazine sulfate as claimed in claim 1, it is characterised in that the aromatic amine described in step one is halogen
For aniline or aniline.
3. the synthetic method of aryl hydrazine sulfate as claimed in claim 2, it is characterised in that the halo aniline described in step one is
Parachloroanilinum or para-bromoaniline.
4. the synthetic method of aryl hydrazine sulfate as claimed in claim 1, it is characterised in that the diazo reagent described in step one
For sodium nitrite, sulphuric acid mass fraction is 40%～65%.
5. the synthetic method of aryl hydrazine sulfate as claimed in claim 1, it is characterised in that the diazo reagent described in step one
For nitrosyl sulfuric acid, sulphuric acid mass fraction is 15%～40%.
6. the synthetic method of aryl hydrazine sulfate as claimed in claim 1, it is characterised in that aromatic amine and diazotising in step one
The ratio of the amount of the material of reagent is 1:1～1.05.
7. the synthetic method of aryl hydrazine sulfate as claimed in claim 1, it is characterised in that reducing agent is sulfurous acid in step 2
One or more in salt, bisulfites, pyrosulfate, aromatic amine are 1 with the ratio of the amount of the material of reducing agent:2～3.5.
8. the synthetic method of aryl hydrazine sulfate as claimed in claim 7, it is characterised in that reducing agent is sulfurous acid in step 2
One or more in sodium, sodium sulfite, sodium pyrosulfate.
9. the synthetic method of aryl hydrazine sulfate as claimed in claim 1, it is characterised in that drip toward reducing solution in step 2
Deca sodium hydroxide solution while diazonium salt, keeps reactant liquor pH to be 4-9 during making reduction reaction.
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Cited By (5)
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| CN107827821A (en) * | 2017-10-31 | 2018-03-23 | 南通醋酸化工股份有限公司 | A kind of pyrazolone series of products continuous stream process for cleanly preparing |
| CN110922340A (en) * | 2019-12-28 | 2020-03-27 | 新华制药（寿光）有限公司 | Synthetic method of phenylhydrazine |
| CN111662206A (en) * | 2020-06-08 | 2020-09-15 | 江苏好收成韦恩农化股份有限公司 | Clean production method of phenylhydrazine compounds |
| CN112939805A (en) * | 2019-12-10 | 2021-06-11 | 江苏优嘉植物保护有限公司 | Preparation method of p-chlorophenylhydrazine sulfate |
| CN113956187A (en) * | 2021-11-08 | 2022-01-21 | 山东省药学科学院 | Synthetic method of p-sulfanilamide phenylhydrazine hydrochloride |
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| CN107827821A (en) * | 2017-10-31 | 2018-03-23 | 南通醋酸化工股份有限公司 | A kind of pyrazolone series of products continuous stream process for cleanly preparing |
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| CN112939805A (en) * | 2019-12-10 | 2021-06-11 | 江苏优嘉植物保护有限公司 | Preparation method of p-chlorophenylhydrazine sulfate |
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| CN111662206A (en) * | 2020-06-08 | 2020-09-15 | 江苏好收成韦恩农化股份有限公司 | Clean production method of phenylhydrazine compounds |
| CN113956187A (en) * | 2021-11-08 | 2022-01-21 | 山东省药学科学院 | Synthetic method of p-sulfanilamide phenylhydrazine hydrochloride |
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