CN113480441A - Method for preparing aminoacetaldehyde dialkyl acetal - Google Patents
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- CN113480441A CN113480441A CN202110658775.8A CN202110658775A CN113480441A CN 113480441 A CN113480441 A CN 113480441A CN 202110658775 A CN202110658775 A CN 202110658775A CN 113480441 A CN113480441 A CN 113480441A
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- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
- C07C213/02—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton by reactions involving the formation of amino groups from compounds containing hydroxy groups or etherified or esterified hydroxy groups
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
- C07C213/08—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton by reactions not involving the formation of amino groups, hydroxy groups or etherified or esterified hydroxy groups
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
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Abstract
The invention discloses a method for preparing aminoacetaldehyde dimethyl acetal, which comprises the following steps: s1, reacting raw materials benzylamine shown in the formula I and the formula II under the action of an acid binding agent to generate a formula III; s2, adding the low-carbon alcohol and the ammonium formate aqueous solution into the formula III in the step S1, mixing, and conveying to a palladium-carbon fixed bed for catalytic reaction to obtain a formula VI; s3, transferring the reaction liquid prepared in the step S2 to a rectifying tower, and distilling to obtain the target product of the formula VI. By adopting the method, the amino acetaldehyde dialkyl acetal with high purity can be prepared, and the industrial production requirement of the amino acetaldehyde dialkyl acetal can be met.
Description
Technical Field
The invention relates to a method for preparing aminoacetaldehyde dialkyl acetal.
Background
Aminoacetaldehyde dialkyl acetals, e.g. aminoacetaldehyde dimethyl acetal, aminoacetaldehyde diethyl acetal, etc., aminoacetaldehyde dimethyl acetal (C)4H12NO2) Aminoacetaldehydydimethyl acetate, also known as Aminoacetaldehyde dimethyl acetal, is a colorless liquid, is commonly used as a pharmaceutical intermediate, for example, in the effective synthesis of proline analogue from ascorbic acid through 3-step reaction, and also in the synthesis of anti-AIDS materialMedicine dolutegravir, anthelmintic praziquantel and the like.
The structural formula of the aminoacetaldehyde dialkyl acetal is as follows:
the traditional process for preparing aminoacetaldehyde dialkyl acetal adopts the route that chloroacetaldehyde dimethyl acetal or chloroacetaldehyde diethyl acetal (the purity is more than 99%) and ammonia water directly carry out high-temperature high-pressure reaction, and then deamination, dehydration, neutralization, distillation and rectification are carried out to obtain the finished product. The traditional process route is a method commonly adopted in industrial production at home and abroad at present, and although the method has mature process and easily available raw materials, the amount of three wastes is large, the yield is low, and the method is not beneficial to industrial production. In addition, excessive ammonia water is needed in the reaction of the traditional process route, so that the PH value is adjusted by alkali liquor, a large amount of water needs to be distilled in the post-treatment, a large amount of energy consumption is consumed, and the environmental protection problem is caused.
In view of this, it is an urgent need to find a preparation method of aminoacetaldehyde dialkyl acetal, which is more favorable for industrial production requirements.
Disclosure of Invention
The invention aims to provide a method for preparing aminoacetaldehyde dialkyl acetal, which can prepare high-purity aminoacetaldehyde dialkyl acetal and meet the requirement of industrial production of aminoacetaldehyde dialkyl acetal.
In order to achieve the purpose, the invention adopts the following technical scheme:
a process for preparing an aminoacetaldehyde dialkyl acetal, comprising the steps of:
s1, reacting the raw materials of formula I and formula II under the action of an acid binding agent to generate a formula III;
s2, mixing the low-carbon alcohol and the ammonium formate aqueous solution with the formula III in the step S1, and conveying the mixture to a palladium-carbon fixed bed for catalytic reaction to obtain a formula VI;
s3, transferring the reaction liquid prepared in the step S2 to a rectifying tower, and distilling to obtain a target product of a formula VI;
the reaction route of the steps is as follows:
preferably, in the step S1, the formula I is added into the reaction vessel, the acid-binding agent is added, the temperature is raised to 120-140 ℃, the formula II is slowly dripped, after the dripping of the formula II is finished, the temperature is kept for 1-2 hours, the temperature is reduced, the filtration is carried out, and the filtrate is decompressed and distilled to obtain the formula III.
Preferably, in the step S2, the prepared ammonium formate aqueous solution is added into the formula III, and after adding the low carbon alcohol, the temperature is raised to 60 to 80 ℃, the palladium-carbon fixed bed containing the palladium-carbon catalyst is raised to 60 to 80 ℃, the conveying flow rate is adjusted, and the retention time is controlled to 10 to 100 min.
Preferably, the molar ratio of the formula I, the formula II, the acid-binding agent and the ammonium formate is as shown in the formula I: formula II: acid binding agent: ammonium formate is 2-4: 1: 1-3: 1-4.
Preferably, the lower alcohol is methanol or ethanol.
Preferably, in the step S3, the reaction liquid prepared in the step S2 is transferred to a rectifying tower, and the fraction below 120 ℃ is collected by atmospheric distillation, and then the fraction between 80 and 120 ℃ is collected by vacuum distillation, so that the target product of the formula VI is obtained.
Preferably, the acid-binding agent is one or a combination of more of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine and pyridine.
Preferably, in the step S1, the reaction temperature of the formula I and the formula II is 120-140 ℃.
Preferably, the palladium-carbon fixed bed adopts a stainless steel pipe, an outer jacket is arranged outside the stainless steel pipe for heating and heat preservation, and a damping pump is adopted to convey the solution III.
Preferably, the debenzylation hydrogenation temperature of the palladium-carbon fixed bed is 60-80 ℃.
The invention has the beneficial effects that:
the invention adopts the intermediate one-pot method to prepare the aminoacetaldehyde dialkyl acetal through continuous reaction, and can obtain the target compound only by simple operation, thereby reducing the charge ratio, saving raw materials, saving cost and simplifying operation. The method has the advantages of mild operation and adjustment, low toxicity, low risk, cheap and easily-obtained raw materials, reduction of generation and treatment of three wastes, capability of obtaining the high-purity aminoacetaldehyde dialkyl acetal as a final product, total yield of more than 90 percent, great significance for large-scale preparation of aminoacetaldehyde dialkyl acetal, accordance with the requirement of industrial mass production and remarkable application value.
Drawings
FIG. 1 is a flow diagram of the process for preparing aminoacetaldehyde dialkyl acetal according to the present invention.
Detailed Description
The technical solution of the present invention will be further described in detail with reference to the following specific examples.
As shown in fig. 1, a method for preparing aminoacetaldehyde dialkyl acetal of the present invention comprises the following steps:
s1, reacting the raw materials of formula I (benzylamine) and formula II (chloroacetaldehyde dialkyl acetal) under the action of an acid-binding agent to generate formula III (N-benzyl-aminoacetaldehyde dialkyl acetal);
s2, mixing the low-carbon alcohol and the ammonium formate aqueous solution with the step III in the S1, and conveying the mixture to a palladium-carbon fixed bed for catalytic reaction to obtain the amino acetaldehyde dialkyl acetal in the formula VI;
s3, transferring the reaction liquid prepared in the step S2 to a rectifying tower, and distilling to obtain a target product of a formula VI;
the reaction route of the steps is as follows:
in some embodiments: in the step S1, the formula I is added into a reaction vessel, the acid-binding agent is added, the temperature is raised to 120-140 ℃, the formula II is slowly dripped, the temperature is kept for 1-2 hours after the dripping of the formula II is finished, the temperature is reduced, the filtration is carried out, and the filtrate is decompressed and distilled to obtain the formula III.
In some embodiments: in the step S2, the prepared ammonium formate aqueous solution is added into the formula III, low-carbon alcohol is added, the temperature is raised to 60-80 ℃, a palladium-carbon fixed bed filled with a palladium-carbon catalyst is heated to 60-80 ℃, the conveying flow rate is adjusted, and the retention time is controlled to be 10-100 min.
In some embodiments: the molar ratio of the acid binding agent to the ammonium formate in the formula I and the formula II is as follows: formula II: acid binding agent: ammonium formate is 2-4: 1: 1-3: 1-4.
In some embodiments: the lower alcohol is methanol or ethanol.
In some embodiments: in the step S3, the reaction liquid prepared in the step S2 is transferred to a rectifying tower, and the distillate with the temperature of below 120 ℃ is collected by atmospheric distillation and then the distillate with the temperature of between 80 and 120 ℃ is collected by vacuum distillation, so that the target product formula VI is obtained.
In some embodiments: the acid-binding agent is one or a combination of more of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine and pyridine.
In some embodiments: in the step S1, the reaction temperature of the formula I and the formula II is 120-140 ℃.
In some embodiments: the palladium-carbon fixed bed adopts a stainless steel pipe, an outer jacket is arranged outside the stainless steel pipe for heating and heat preservation, and the palladium-carbon fixed bed adoptsDampingThe pump delivers the formula III solution. Specifically, the diameter of the stainless steel pipe is DN25, the length of the stainless steel pipe is 3 meters, the flow rate of a damping pump is 0-300 ML/min, the loading capacity of a 5% particle palladium-carbon catalyst is 200g of dry basis (600 g of wet product), the volume of a feed is about 1L, and the activity time of the palladium-carbon catalyst is 1400 hours continuously.
In some embodiments: the debenzylation hydrogenation temperature of the palladium-carbon fixed bed is 60-80 ℃.
The following 2 specific examples for the preparation of aminoacetaldehyde dimethyl acetal are listed:
implementation 1:
this example of a process for the preparation of aminoacetaldehyde dimethyl acetal comprises the following steps:
1) preparation of formula III: adding benzylamine formula I (428g, 4mol) into a reaction bottle, then adding acid-binding agent potassium carbonate (276g, 2mol), heating to 120-125 ℃, controlling the temperature to 120-125 ℃, starting to slowly dropwise add formula II (R is methyl, 248g, 2mol), after dropwise adding, preserving heat for 1-2 hours, cooling, filtering, decompressing and distilling the filtrate to recover benzylamine to obtain a residual liquid formula III (385g), and directly feeding the residual liquid formula III to the next step for reaction.
2) Preparation of aminoacetaldehyde dimethyl acetal: adding 1000ML of methanol, 50g of water and 126g of ammonium formate (2 mol) into the residual liquid formula III obtained in the step, heating to 60-65 ℃, raising the temperature of a palladium-carbon fixed bed to 60-65 ℃, starting a damping pump, adjusting the flow rate to 20ML/min, and controlling the retention time to 10-100min (namely, the time from the beginning of feeding to the discharging is 10-100 min). After the reaction liquid is pumped, 1000ML methanol is pumped to replace the reaction liquid in the palladium-carbon fixed bed, the reaction liquid is transferred into a rectifying tower, the distillate below 120 ℃ is collected by atmospheric distillation, the vacuum degree of the vacuum distillation is less than minus 0.097Mpa, the distillate at 80 to 120 ℃ is collected, and the aminoacetaldehyde dimethyl acetal (190g, 1.8094mol) is obtained, the molar yield is 90 percent, and the purity is more than 98 percent.
Implementation 2:
this example of a process for the preparation of aminoacetaldehyde dimethyl acetal comprises the following steps:
1) preparation of formula III: adding benzylamine formula I (856g, 8mol) into a reaction bottle, then adding acid-binding agent potassium carbonate (414g,3mol), heating to 120-.
2) Preparation of aminoacetaldehyde dimethyl acetal: adding 1000ML of ethanol, 50g of water and ammonium formate (252g, 4mol) into the residual liquid formula III obtained in the step, heating to 60-80 ℃, heating the palladium-carbon fixed bed to 60-80 ℃, starting a damping pump, adjusting the flow rate to 20ML/min, and controlling the retention time to 10-100min (namely, the time from the beginning of feeding to the discharging is 10-100 min). After the reaction liquid is pumped, 1000ML methanol is pumped to replace the reaction liquid in the palladium-carbon fixed bed, the reaction liquid is transferred into a rectifying tower, the distillate below 120 ℃ is collected by atmospheric distillation, the vacuum degree of reduced pressure distillation is less than minus 0.097Mpa, the distillate at 80 to 120 ℃ is collected, and aminoacetaldehyde dimethyl acetal (192g, 1.8286mol) is obtained, the molar yield is 91.4 percent, and the purity is more than 98 percent.
The following 2 specific examples for the preparation of aminoacetaldehyde diethyl acetal are listed:
implementation 3:
the process for the preparation of aminoacetaldehyde diethyl acetal of this example comprises the following steps:
1) preparation of formula III: adding benzylamine formula I (428g, 4mol) into a reaction bottle, then adding acid-binding agent potassium carbonate (276g, 2mol), heating to 120-125 ℃, controlling the temperature to 120-125 ℃, starting to slowly dropwise add formula II (R is ethyl, 266g, 2mol), after dropwise adding, preserving heat for 1-2 hours, cooling, filtering, decompressing and distilling the filtrate to recover benzylamine to obtain a residual solution formula III (440g), and directly feeding the residual solution formula III to the next step for reaction.
2) Preparation of aminoacetaldehyde diethyl acetal: adding 1000ML of methanol, 50g of water and 126g of ammonium formate (2 mol) into the residual liquid formula III obtained in the step, heating to 60-65 ℃, raising the temperature of a palladium-carbon fixed bed to 60-65 ℃, starting a damping pump, adjusting the flow rate to 20ML/min, and controlling the retention time to 10-100min (namely, the time from the beginning of feeding to the discharging is 10-100 min). After the reaction liquid is pumped, 1000ML methanol is pumped to replace the reaction liquid in the palladium-carbon fixed bed, the reaction liquid is transferred into a rectifying tower, the distillate with the temperature below 120 ℃ is collected by atmospheric distillation, the vacuum degree of reduced pressure distillation is less than minus 0.097Mpa, the distillate with the temperature of 90 to 120 ℃ is collected, and the aminoacetaldehyde diethyl acetal (239.4g, 1.8mol) is obtained, the molar yield is 90 percent, and the purity is more than 98 percent. Implementation 4:
the process for the preparation of aminoacetaldehyde diethyl acetal of this example comprises the following steps:
1) preparation of formula III: adding benzylamine formula I (856g, 8mol) into a reaction bottle, then adding acid-binding agent potassium carbonate (414g,3mol), heating to 120-.
2) Preparation of aminoacetaldehyde diethyl acetal: adding 1000ML of ethanol, 50g of water and ammonium formate (252g, 4mol) into the residual liquid formula III obtained in the step, heating to 60-80 ℃, raising the temperature of a palladium-carbon fixed bed to 60-80 ℃, starting a damping pump, adjusting the flow rate to 20ML/min, and controlling the retention time to 10-100min (namely, the time from the beginning of feeding to the discharging is 10-100 min). After the reaction liquid is pumped, 1000ML methanol is pumped to replace the reaction liquid in the palladium-carbon fixed bed, the reaction liquid is transferred into a rectifying tower, the distillate with the temperature below 120 ℃ is collected by atmospheric distillation, the vacuum degree of the vacuum distillation is less than minus 0.097Mpa, the distillate with the temperature of 80 to 120 ℃ is collected, and the aminoacetaldehyde diethyl acetal (241g, 1.812mol) is obtained, the molar yield is 90.6 percent, and the purity is more than 98 percent.
Finally, it is necessary to point out that: the above embodiments are merely illustrative of the present invention, and should not be construed as limiting the scope of the invention, and the non-essential modifications and improvements made by those skilled in the art according to the above disclosure are within the scope of the invention.
Claims (10)
1. A method for preparing aminoacetaldehyde dialkyl acetal, which is characterized by comprising the following steps:
s1, reacting the raw materials of formula I and formula II under the action of an acid binding agent to generate a formula III;
s2, mixing the low-carbon alcohol and the ammonium formate aqueous solution with the formula III in the step S1, and conveying the mixture to a palladium-carbon fixed bed for catalytic reaction to obtain a formula VI;
s3, transferring the reaction liquid prepared in the step S2 to a rectifying tower, and distilling to obtain a target product of a formula VI;
the reaction route of the steps is as follows:
2. the method for preparing aminoacetaldehyde dialkyl acetal as claimed in claim 1, wherein in step S1, the formula I is added into the reaction vessel, the acid-binding agent is added, the temperature is raised to 120-140 ℃, the formula II is slowly dropped, after the dropping of the formula II, the temperature is kept for 1-2 hours, the temperature is reduced, the filtration is carried out, and the filtrate is distilled under reduced pressure to obtain the formula III.
3. The method for preparing aminoacetaldehyde dialkyl acetal according to claim 1, wherein in step S2, the prepared ammonium formate aqueous solution is added into formula III, and the lower alcohol is added, then the temperature is raised to 60-80 ℃, the temperature of the palladium-carbon fixed bed containing palladium-carbon catalyst is raised to 60-80 ℃, the conveying flow rate is adjusted, and the retention time is controlled to 10-100 min.
4. The method of claim 1, wherein the molar ratio of the formula I, the formula II, the acid-binding agent and the ammonium formate is as follows: formula II: acid binding agent: ammonium formate is 2-4: 1: 1-3: 1-4.
5. The method of claim 3, wherein the lower alcohol is methanol or ethanol.
6. The method for preparing aminoacetaldehyde dialkyl acetal according to claim 1, wherein in step S3, the reaction solution obtained in step S2 is transferred to a rectifying tower, and the distillation under atmospheric pressure is firstly carried out to collect the fraction below 120 ℃, and then the distillation under reduced pressure is carried out to collect the fraction at 80-120 ℃ to obtain the target product of formula VI.
7. The method for preparing aminoacetaldehyde dialkyl acetal according to claim 1, wherein the acid-binding agent is one or more of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine and pyridine.
8. The method as claimed in claim 1, wherein the reaction temperature of the reaction between formula I and formula II in step S1 is 120-140 ℃.
9. The method for preparing aminoacetaldehyde dialkyl acetal according to claim 1, wherein the palladium-carbon fixed bed is made of stainless steel tube, the stainless steel tube is externally provided with jacket for heating and heat preservation, and the solution of formula III is conveyed by damping pump.
10. The method for preparing aminoacetaldehyde dialkyl acetal according to claim 1, wherein the fixed bed debenzylation hydrogenation temperature of palladium-carbon is 60-80 ℃.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130289275A1 (en) * | 2010-12-13 | 2013-10-31 | Sequent Scientific Limited | Process for the preparation of praziquantel |
| RU2654853C1 (en) * | 2017-11-02 | 2018-05-23 | федеральное государственное бюджетное образовательное учреждение высшего образования "Алтайский государственный университет" | Method of production amoloacethaldehyde dialkyl acetals by restoring aziloacethdehyde dialkyl acetals by triphyliphosphin |
| CN110015964A (en) * | 2019-04-30 | 2019-07-16 | 内蒙古圣氏化学股份有限公司 | A kind of aminoacetaldehyde dimethyl acetal production technology |
| CN112375003A (en) * | 2020-11-13 | 2021-02-19 | 内蒙古圣氏化学股份有限公司 | Production process of high-purity aminoacetaldehyde dimethyl acetal |
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- 2021-06-15 CN CN202110658775.8A patent/CN113480441A/en not_active Withdrawn
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130289275A1 (en) * | 2010-12-13 | 2013-10-31 | Sequent Scientific Limited | Process for the preparation of praziquantel |
| RU2654853C1 (en) * | 2017-11-02 | 2018-05-23 | федеральное государственное бюджетное образовательное учреждение высшего образования "Алтайский государственный университет" | Method of production amoloacethaldehyde dialkyl acetals by restoring aziloacethdehyde dialkyl acetals by triphyliphosphin |
| CN110015964A (en) * | 2019-04-30 | 2019-07-16 | 内蒙古圣氏化学股份有限公司 | A kind of aminoacetaldehyde dimethyl acetal production technology |
| CN112375003A (en) * | 2020-11-13 | 2021-02-19 | 内蒙古圣氏化学股份有限公司 | Production process of high-purity aminoacetaldehyde dimethyl acetal |
Non-Patent Citations (2)
| Title |
|---|
| BRINGMANN GERHARD等: "A simple, chiral-pool-independent synthesis of enantiomerically pure alanine-derived α-amino aldehyde acetals" * |
| MARIA ISABEL MONTANEZ等: "Synthetic Approach to Gain Insight into Antigenic Determinants of Cephalosporins: In Vitro Studies of Chemical Structure_IgE Molecular Recognition Relationships" * |
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Application publication date: 20211008 |