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CN111484426A - Method for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid - Google Patents

Method for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid Download PDF

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Publication number
CN111484426A
CN111484426A CN202010418334.6A CN202010418334A CN111484426A CN 111484426 A CN111484426 A CN 111484426A CN 202010418334 A CN202010418334 A CN 202010418334A CN 111484426 A CN111484426 A CN 111484426A
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Prior art keywords
aminoacetonitrile
synthesizing
ammonia
hydrocyanic acid
aminoacetonitrile hydrochloride
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Inventor
刘子程
麻勇
任江胜
刘玉宝
安东亮
吴丹
李雪研
纪宇
侯奕彤
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Yingkou Derui Chemical Co ltd
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Yingkou Derui Chemical Co ltd
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    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C253/00Preparation of carboxylic acid nitriles
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C253/00Preparation of carboxylic acid nitriles
    • C07C253/30Preparation of carboxylic acid nitriles by reactions not involving the formation of cyano groups

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Abstract

The invention relates to the technical field of organic chemical synthesis, in particular to a method for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid, which comprises the following steps: firstly, hydrocyanic acid reacts with formaldehyde to obtain an aqueous solution of hydroxyacetonitrile, then the hydroxyacetonitrile reacts with ammonia to obtain an aqueous solution of aminoacetonitrile, finally the aminoacetonitrile reacts with hydrogen chloride, and the obtained feed liquid is concentrated, crystallized, filtered and dried to obtain aminoacetonitrile hydrochloride. The method provided by the invention has the advantages of simple process, mild reaction conditions, no high-temperature and high-pressure operation, and conventional equipment; except hydrocyanic acid, other raw materials are easy to obtain, and the raw material cost is lower; the amount of waste water and waste gas is small, the waste water and the waste gas can be used indiscriminately, and only a small amount of ammonium chloride is generated; the product has good quality, and the appearance and the content are higher than those of the sodium cyanide process.

Description

Method for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid
Technical Field
The invention relates to the technical field of organic chemical synthesis, in particular to a method for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid.
Background
The aminoacetonitrile hydrochloride is an important intermediate of medicines and pesticides, and can be used for synthesizing various organic compounds, such as a plant growth regulator thidiazuron, a brain function improver oxiracetam, an antirheumatic drug Iguratimod, an ocular hypotensive drug timolol and the like.
At present, the commonly adopted process is that sodium cyanide, formaldehyde, ammonium chloride and the like are used as raw materials to synthesize a one-step intermediate methylene amino acetonitrile, and then the methylene amino acetonitrile reacts in a hydrogen chloride alcohol solution to obtain amino acetonitrile hydrochloride. The disadvantages of this method are mainly three points: firstly, the process is long, three times of solid-liquid separation and two times of solid drying are needed, the production period is long, the energy consumption is large, and the equipment occupation is large. Secondly, the wastewater amount is large, and the wastewater is difficult to treat due to high cyanide, high COD, high ammonia nitrogen and high salt, so that the wastewater treatment cost is increased. Thirdly, the yield is low and the product quality is unstable.
Disclosure of Invention
In order to solve the technical problems, the invention provides a method for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid, which comprises the following steps: firstly, hydrocyanic acid reacts with formaldehyde to obtain an aqueous solution of hydroxyacetonitrile, then the hydroxyacetonitrile reacts with ammonia to obtain an aqueous solution of aminoacetonitrile, finally the aminoacetonitrile reacts with hydrogen chloride, and the obtained feed liquid is concentrated, crystallized, filtered and dried to obtain aminoacetonitrile hydrochloride.
The invention is realized in such a way that the method for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid comprises the following steps:
1) taking hydrocyanic acid and formaldehyde as raw materials, and reacting under the catalysis of alkaline inorganic salt to obtain an aqueous solution of hydroxyacetonitrile:
Figure BDA0002495924610000021
2) controlling the temperature to be 0-100 ℃, and reacting the hydroxyl acetonitrile water solution obtained in the step 1) with excessive ammonia for 0.5-5h to obtain an amino acetonitrile water solution:
Figure BDA0002495924610000022
deaminating the aqueous aminoacetonitrile solution;
3) controlling the temperature to be 0-100 ℃, and reacting the aminoacetonitrile aqueous solution obtained in the step 2) with hydrogen chloride for 0.5-5h to obtain an aminoacetonitrile hydrochloride aqueous solution:
Figure BDA0002495924610000023
dehydrochlorination of aminoacetonitrile hydrochloride water solution, concentration, crystallization, filtration and drying to obtain aminoacetonitrile hydrochloride.
Preferably, in the step 2), the ammonia is ammonia gas or ammonia water with any concentration, and the molar ratio of the raw materials is hydroxy acetonitrile to ammonia is 1: 1-5.
More preferably, in step 2), the ammonia is ammonia gas, and the molar ratio of the raw materials is hydroxyacetonitrile to ammonia is 1: 1.1-3.
More preferably, in the step 2), the reaction temperature is 20-30 ℃ and the reaction time is 1-2 h.
Further preferably, in step 2), the charging sequence is to add the aqueous hydroxyacetonitrile solution into the ammonia, and the reactor is a reaction kettle, a tubular reactor, a microchannel reactor or a tower reactor.
More preferably, in step 3), the hydrogen chloride is hydrogen chloride gas or hydrochloric acid with any concentration, and the molar ratio of the raw materials is aminoacetonitrile: hydrogen chloride 1: 1-5.
More preferably, in step 3), the hydrogen chloride is hydrogen chloride gas, and the molar ratio of the raw materials is aminoacetonitrile: hydrogen chloride 1: 1.1-1.5.
More preferably, in the step 3), the reaction temperature is 20-30 ℃ and the reaction time is 1-2 h.
Further preferably, in the step 3), the hydrogen chloride is added into the aminoacetonitrile in the feeding sequence, and the reactor is a reaction kettle, a tubular reactor, a microchannel reactor or a tower reactor.
Compared with the prior art, the invention has the advantages that: the synthesis method synthesizes aminoacetonitrile hydrochloride by using hydrocyanic acid, formaldehyde, ammonia and hydrogen chloride as raw materials, and has the following four advantages:
1. the process is simple, the reaction condition is mild, high-temperature and high-pressure operation is not involved, and the used equipment is conventional equipment;
2. except hydrocyanic acid, other raw materials are easy to obtain, and the raw material cost is lower;
3. the amount of waste water and waste gas is small, the waste water and the waste gas can be used indiscriminately, and only a small amount of ammonium chloride is generated;
4. the product has good quality, and the appearance and the content are higher than those of the sodium cyanide process.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example 1:
1) synthesizing hydroxyl acetonitrile according to a general process;
2) adding 102 g of 25% ammonia water into a 500m L four-mouth reaction bottle, stirring, controlling the temperature to be 20-30 ℃, slowly adding 114 g of 50% hydroxy acetonitrile dropwise, keeping the temperature and stirring for 1.5 hours, and deaminating to obtain the amino acetonitrile.
3) Controlling the temperature to be 20-30 ℃, and slowly dripping 183 g of 30% hydrochloric acid into the reaction bottle. Stirring for 2 hours under heat preservation. Dehydrochlorination, low-temperature negative-pressure concentration to obtain a certain amount of water, cooling crystallization, filtering, vacuum drying to obtain dry aminoacetonitrile hydrochloride powder with appearance similar to white crystal powder. Weight 75.5 g, yield 81.6% (based on hydroxyacetonitrile). The content is 99.3%.
Example 2:
1) synthesizing hydroxyl acetonitrile according to a general process;
2) adding 114 g of 50% hydroxy acetonitrile into a 500m L four-mouth reaction bottle, stirring, controlling the temperature to be 20-30 ℃, quickly introducing 25.5 g of ammonia gas, keeping the temperature and stirring for 1.5 hours, and deaminating to obtain aminoacetonitrile;
3) controlling the temperature of 30 ℃ to be 20-30 ℃, and slowly introducing 55 g of hydrogen chloride gas into the reaction bottle. Stirring for 2 hours under heat preservation. Dehydrochlorination, low-temperature negative-pressure concentration to obtain a certain amount of water, cooling crystallization, filtering, vacuum drying to obtain dry aminoacetonitrile hydrochloride powder with appearance similar to white crystal powder. 76 g in weight, yield 82.2% (based on hydroxyacetonitrile). The content is 99.6%.
Example 3:
1) synthesizing hydroxyl acetonitrile according to a general process;
2) and (2) adding 75 g of 25% ammonia water into a 500m L four-mouth reaction bottle, stirring, controlling the temperature to be 20-30 ℃, slowly dropwise adding 114 g of 50% hydroxyacetonitrile, preserving the temperature, stirring for 1.5 hours, and deaminating to obtain the aminoacetonitrile.
3) Controlling the temperature to be 20-30 ℃, and slowly dripping 134 g of 30% hydrochloric acid into the reaction bottle. Stirring for 2 hours under heat preservation. Dehydrochlorination, low-temperature negative-pressure concentration to obtain a certain amount of water, cooling crystallization, filtering, vacuum drying to obtain dry aminoacetonitrile hydrochloride powder with appearance similar to white crystal powder. Weight 74 g, yield 80% (based on hydroxyacetonitrile). The content is 99.3%.
Example 4:
1) synthesizing hydroxyl acetonitrile according to a general process;
2) and (2) adding 102 g of 25% ammonia water into a 500m L four-mouth reaction bottle, stirring, controlling the temperature to be 10-20 ℃, slowly dropwise adding 114 g of 50% hydroxyacetonitrile, preserving the temperature, stirring for 3 hours, and deaminating to obtain the aminoacetonitrile.
3) Controlling the temperature to be 10-20 ℃, and slowly dripping 183 g of 30% hydrochloric acid into the reaction bottle. Stirring for 3 hours under heat preservation. Dehydrochlorination, low-temperature negative-pressure concentration to obtain a certain amount of water, cooling crystallization, filtering, vacuum drying to obtain dry aminoacetonitrile hydrochloride powder with appearance similar to white crystal powder. Weight 74.2 g, yield 80.2% (based on hydroxyacetonitrile). The content is 99.4%.
Example 5:
1) synthesizing hydroxyl acetonitrile according to a general process;
2) adding 204 g of 25% ammonia water into a 500m L four-mouth reaction bottle, stirring, controlling the temperature to be 20-30 ℃, slowly adding 114 g of 50% hydroxy acetonitrile dropwise, keeping the temperature and stirring for 1.5 hours, and deaminating to obtain the amino acetonitrile.
3) Controlling the temperature to be 20-30 ℃, and slowly dripping 183 g of 30% hydrochloric acid into the reaction bottle. Stirring for 2 hours under heat preservation. Dehydrochlorination, low-temperature negative-pressure concentration to obtain a certain amount of water, cooling crystallization, filtering, vacuum drying to obtain dry aminoacetonitrile hydrochloride powder with appearance similar to white crystal powder. 76.3 g in weight, yield 82.5% (based on hydroxyacetonitrile). The content is 99.5%.
Example 6:
1) synthesizing hydroxyl acetonitrile according to a general process;
2) adding 114 g of 50% hydroxy acetonitrile into a 500m L four-mouth reaction bottle, stirring, controlling the temperature to be 20-30 ℃, quickly introducing 51 g of ammonia gas, keeping the temperature, stirring for 1.5 hours, and deaminating to obtain aminoacetonitrile;
3) and controlling the temperature of 30 ℃ to be 20-30 ℃, and slowly dripping 183 g of 30% hydrochloric acid into the reaction bottle. Stirring for 2 hours under heat preservation. Dehydrochlorination, low-temperature negative-pressure concentration to obtain a certain amount of water, cooling crystallization, filtering, vacuum drying to obtain dry aminoacetonitrile hydrochloride powder with appearance similar to white crystal powder. Weight 75.7 g, yield 81.8% (based on hydroxyacetonitrile). The content is 99.6%.
Example 7:
1) synthesizing hydroxyl acetonitrile according to a general process;
2) adding 102 g of 25% ammonia water into a 500m L four-mouth reaction bottle, stirring, controlling the temperature to be 20-30 ℃, slowly adding 114 g of 50% hydroxy acetonitrile dropwise, keeping the temperature and stirring for 1.5 hours, and deaminating to obtain the amino acetonitrile.
3) Controlling the temperature to be 20-30 ℃, and slowly introducing 47.5 g of hydrogen chloride gas into the reaction bottle. Stirring for 2 hours under heat preservation. Dehydrochlorination, low-temperature negative-pressure concentration to obtain a certain amount of water, cooling crystallization, filtering, vacuum drying to obtain dry aminoacetonitrile hydrochloride powder with appearance similar to white crystal powder. 76 g in weight, yield 82.2% (based on hydroxyacetonitrile). The content is 99.5%.
Example 8:
1) synthesizing hydroxyl acetonitrile according to a general process;
2) adding 102 g of 25% ammonia water into a 500m L four-mouth reaction bottle, stirring, controlling the temperature to be 40-50 ℃, slowly adding 114 g of 50% hydroxy acetonitrile dropwise, keeping the temperature and stirring for 1 hour, and deaminating to obtain the amino acetonitrile.
3) Controlling the temperature to be 40-50 ℃, and slowly dripping 183 g of 30% hydrochloric acid into the reaction bottle. Stirring for 1 hour under heat preservation. Dehydrochlorination, low-temperature negative-pressure concentration to obtain a certain amount of water, cooling crystallization, filtering, vacuum drying to obtain dry aminoacetonitrile hydrochloride powder with appearance similar to white crystal powder. Weight 74 g, yield 80% (based on hydroxyacetonitrile). The content is 99.4%.
Example 9:
1) synthesizing hydroxyl acetonitrile according to a general process;
2) adding 114 g of 50% hydroxy acetonitrile into a 500m L four-mouth reaction bottle, stirring, controlling the temperature to be 20-30 ℃, rapidly introducing 85 g of ammonia gas, keeping the temperature, stirring for 1 hour, and deaminating to obtain aminoacetonitrile;
3) and controlling the temperature of 30 ℃ to be 20-30 ℃, and slowly dripping 183 g of 30% hydrochloric acid into the reaction bottle. Stirring for 2 hours under heat preservation. Dehydrochlorination, low-temperature negative-pressure concentration to obtain a certain amount of water, cooling crystallization, filtering, vacuum drying to obtain dry aminoacetonitrile hydrochloride powder with appearance similar to white crystal powder. 76.6 g in weight, yield 82.8% (based on hydroxyacetonitrile). The content is 99.6%.
The embodiments of the present invention have been described in detail, but the present invention is not limited to the above embodiments, and various changes can be made without departing from the gist of the present invention within the knowledge of those skilled in the art.

Claims (9)

1. A method for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid is characterized by comprising the following steps:
1) taking hydrocyanic acid and formaldehyde as raw materials, and reacting under the catalysis of alkaline inorganic salt to obtain an aqueous solution of hydroxyacetonitrile:
Figure FDA0002495924600000011
2) controlling the temperature to be 0-100 ℃, and reacting the hydroxyl acetonitrile water solution obtained in the step 1) with excessive ammonia for 0.5-5h to obtain an amino acetonitrile water solution:
Figure FDA0002495924600000012
deaminating the aqueous aminoacetonitrile solution;
3) controlling the temperature to be 0-100 ℃, and reacting the aminoacetonitrile aqueous solution obtained in the step 2) with hydrogen chloride for 0.5-5h to obtain an aminoacetonitrile hydrochloride aqueous solution:
Figure FDA0002495924600000013
dehydrochlorination of aminoacetonitrile hydrochloride water solution, concentration, crystallization, filtration and drying to obtain aminoacetonitrile hydrochloride.
2. The method for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid according to claim 1, wherein in the step 2), the ammonia is ammonia gas or ammonia water of any concentration, and the molar ratio of the raw materials is hydroxyacetonitrile to ammonia is 1: 1-5.
3. The method for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid according to claim 2, wherein in the step 2), the ammonia is ammonia gas, and the molar ratio of the starting material is hydroxyacetonitrile to ammonia is 1: 1.1-3.
4. The process for synthesizing aminoacetonitrile hydrochloride of claim 1 wherein, in the step 2), the reaction temperature is 20 to 30 ℃ and the reaction time is 1 to 2 hours.
5. The process for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid according to claim 1, wherein in step 2) the sequence of addition is to add aqueous hydroxyethylnitrile to ammonia, and the reactor is a reaction vessel, a tubular reactor, a microchannel reactor or a column reactor.
6. The method for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid according to claim 1, wherein in step 3), the hydrogen chloride is hydrogen chloride gas or hydrochloric acid of any concentration, and the molar ratio of the raw materials is aminoacetonitrile: hydrogen chloride 1: 1-5.
7. The method for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid according to claim 6, wherein in step 3), the hydrogen chloride is hydrogen chloride gas, and the molar ratio of the raw materials is aminoacetonitrile: hydrogen chloride 1: 1.1-1.5.
8. The process for synthesizing aminoacetonitrile hydrochloride of claim 1 wherein, in the step 3), the reaction temperature is 20 to 30 ℃ and the reaction time is 1 to 2 hours.
9. The process for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid according to claim 1, wherein in step 3), the order of addition is such that hydrogen chloride is added to aminoacetonitrile, and the reactor is a reaction vessel, a tubular reactor, a microchannel reactor or a column reactor.
CN202010418334.6A 2020-05-18 2020-05-18 Method for synthesizing aminoacetonitrile hydrochloride from hydrocyanic acid Pending CN111484426A (en)

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CN116023341A (en) * 2023-03-28 2023-04-28 山东国邦药业有限公司 Synthesis process of 2-methylpyrazine
CN117164479A (en) * 2023-08-21 2023-12-05 甘肃康巴斯生物科技有限公司 Preparation method of aminoacetonitrile hydrochloride

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