KR20010042773A - Process for producing dimethylacetamide - Google Patents
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- KR20010042773A KR20010042773A KR1020007011509A KR20007011509A KR20010042773A KR 20010042773 A KR20010042773 A KR 20010042773A KR 1020007011509 A KR1020007011509 A KR 1020007011509A KR 20007011509 A KR20007011509 A KR 20007011509A KR 20010042773 A KR20010042773 A KR 20010042773A
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- C07C231/02—Preparation of carboxylic acid amides from carboxylic acids or from esters, anhydrides, or halides thereof by reaction with ammonia or amines
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Abstract
(a) 1.01 이상의 디메틸아민 대 아세트산의 몰비에서 상압하에 아세트산을 디메틸아민으로 중화시켜 디메틸아민 아세테이트를 합성하고, 그에 의해 합성된 디메틸아민 아세테이트를 함유하는 반응 생성액을 수득하는 중화반응단계, 그리고 (b) 상기 반응 생성액을 가압하에 아미드화 반응시키는 아미드화 반응 단계를 포함하는, 아세트산과 디메틸아민으로부터 디메틸아세트아미드의 제조 방법.(a) a neutralization step of neutralizing acetic acid with dimethylamine at atmospheric pressure at a molar ratio of at least 1.01 dimethylamine to acetic acid to synthesize dimethylamine acetate, thereby obtaining a reaction product containing the synthesized dimethylamine acetate, and ( b) an amidation reaction step of amidating the reaction product liquid under pressure, a process for producing dimethylacetamide from acetic acid and dimethylamine.
Description
지금까지 아세트산과 디메틸아민으로부터 디메틸아세트아미드를 제조하는 방법은 상압에서 수행되어 왔지만, 낮은 수율과 장시간의 반응이라는 단점을 가지고 있었다. 따라서, 일본특허공고공보 소53-82716 호는 아세트산과 디메틸아민이 도입되는 곳에 촉매로서 몰리브덴 옥사이드를 첨가함으로써, 수율을 개선시키고, 반응시간을 단축하는 방법이 제안되었다. 그러나, 이러한 방법에 의해서도, 반응시간은 충분히 단축되지 않았다. 일본특허공개공보 평6-279375 호는 가압하에 카르복실산과 아민을 반응시키고, 동시에 반응수를 제거함으로써 카르복실산 아미드를 제조하는 방법을 제안하였다. 그러나, 상기 방법에서 사용되는 가압장치 재료는 산에 저항력이 있는 것이어야하며, 탈수장치가 가압장치에 부착되어 있어야하므로, 장치비가 높다는 단점을 가지고 있다.Until now, the process for preparing dimethylacetamide from acetic acid and dimethylamine has been carried out at atmospheric pressure, but has a disadvantage of low yield and long time reaction. Therefore, Japanese Patent Application Laid-open No. 53-82716 proposes a method of improving the yield and shortening the reaction time by adding molybdenum oxide as a catalyst where acetic acid and dimethylamine are introduced. However, even by this method, the reaction time was not sufficiently shortened. Japanese Patent Laid-Open No. 6-279375 proposes a method for producing a carboxylic acid amide by reacting a carboxylic acid with an amine under pressure and simultaneously removing the reaction water. However, the pressurizer material used in the method should be acid resistant, and since the dehydrator should be attached to the pressurizer, the apparatus cost is high.
본 발명은 아세트산과 디메틸아민과의 반응을 통해 우수한 효율로 디메틸아세트아미드를 제조하는 방법에 관한 것이다. 디메틸아세트아미드는 용매로서 및 유기합성과 약학 등의 생원료로서 산업적으로 유용한 물질이다.The present invention relates to a process for preparing dimethylacetamide with good efficiency through the reaction of acetic acid with dimethylamine. Dimethylacetamide is an industrially useful material as a solvent and as a raw material for organic synthesis and pharmaceuticals.
본 발명은 선행 기술의 상기 언급된 문제의 측면에서 완성된 것으로서, 본 발명의 목적은 반응시간이 단축되고, 장치가 간단하며, 디메틸아세트아미드가 우수한 효율로 제조되는 아세트산과 디메틸아민의 반응을 통한 디메틸아세트아미드의 공업적인 제조 방법을 제공하는데 있다.The present invention has been completed in view of the above-mentioned problems of the prior art, and an object of the present invention is to reduce the reaction time, to simplify the apparatus, and to react the acetic acid with dimethylamine, in which dimethylacetamide is produced with excellent efficiency. It is to provide an industrial production method of dimethylacetamide.
본 발명자들은 상기 언급된 문제를 해결하기위해 광범위한 연구를 수행하였으며, 그 결과 아세트산과 디메틸아민으로부터 디메틸아세트아미드를 제조하는 방법에서, 디메틸아민 아세테이트가 100 ℃이상의 온도에서, 서서히 아세트산과 디메틸아민으로 분해하므로, 디메틸아세트아미드의 수율을 개선하기위해서는 아미드화 반응시간을 단축시키는 것이 중요하다는 것을 발견하였다. 따라서, 본 발명자들은 상업과 상온에서 아세트산을 디메틸아민으로 중화시키고, 이어서 중화된 생성물을 가압하에 분해 반응시킴으로써 소량의 불순물을 함유하고 있는 디메틸아세트아미드 수용액을 단시간내 고수율로 수득할수 있다는 것을 발견하였으며, 따라서 본 발명을 완성하였다.The present inventors have conducted extensive research to solve the above-mentioned problems, and as a result, in the process for preparing dimethylacetamide from acetic acid and dimethylamine, dimethylamine acetate is slowly decomposed into acetic acid and dimethylamine at a temperature of 100 ° C. or more. Therefore, it was found that it is important to shorten the amidation reaction time in order to improve the yield of dimethylacetamide. Accordingly, the present inventors have found that an aqueous solution of dimethylacetamide containing a small amount of impurities can be obtained in high yield in a short time by neutralizing acetic acid with dimethylamine at commercial and normal temperature and then decomposing the neutralized product under pressure. Therefore, this invention was completed.
따라서, 본 발명에 따라, (a) 1.01 이상의 디메틸아민 대 아세트산의 몰비에서 상압하에 아세트산을 디메틸아민으로 중화시켜 디메틸아민 아세테이트를 합성하고, 그에 의해 합성된 디메틸아민 아세테이트를 함유하는 반응 생성액을 수득하는 중화반응단계, 그리고 (b) 상기 반응 생성액을 가압하에 아미드화 반응시키는 아미드화 반응 단계를 포함하는 아세트산과 디메틸아민으로부터 디메틸아세트아미드를 제조하는 방법을 제공한다.Thus, according to the present invention, (a) neutralizing acetic acid with dimethylamine under atmospheric pressure at a molar ratio of at least 1.01 dimethylamine to acetic acid to synthesize dimethylamine acetate, thereby obtaining a reaction product containing the synthesized dimethylamine acetate. It provides a method for producing dimethylacetamide from acetic acid and dimethylamine comprising a neutralization step of the step, and (b) an amidation step of amidating the reaction product liquid under pressure.
본 발명을 수행하기위한 최선의 형태Best Mode for Carrying Out the Invention
본 발명은 하기에 상세하게 기술되어 있다.The invention is described in detail below.
본 발명의 방법에서 원료로 사용된 아세트산과 디메틸아민은 바람직하게는 가능한 고순도의 것이다. 하지만, 또한 공업용 순도의 것도 사용될수 있다.Acetic acid and dimethylamine used as raw materials in the process of the invention are preferably of the highest purity possible. However, also industrial purity may be used.
본 발명의 방법중 중화 반응단계에서, 아세트산과 디메틸아민은 반응 용기에 공급되어 물과 촉매의 모두의 부재하에 중화되어 디메틸아민 아세테이트를 합성함으로써 이를 함유하는 반응 생성액을 수득한다.In the neutralization step of the process of the present invention, acetic acid and dimethylamine are fed to the reaction vessel and neutralized in the absence of both water and catalyst to synthesize dimethylamine acetate to obtain a reaction product liquid containing the same.
아세트산과 디메틸아민은 동시에 반응 용기에 공급하거나 혹은 아세트산을 먼저 공급한 후 디메틸아민을 거기에 공급할수 있다. 반응물의 비에 대해서는, 디메틸아민이 아세트산에 대해 과량으로 존재하는 것이 바람직하다. 즉, 디메틸아민 대 아세트산의 몰비는 1.01 이상이며, 더 바람직하게는 1.01 내지 1.5이고, 더욱 바람직하게는 1.01 내지 1.20이다.Acetic acid and dimethylamine can be fed to the reaction vessel at the same time or acetic acid is fed first followed by dimethylamine. As for the ratio of reactants, it is preferred that dimethylamine is present in excess of acetic acid. That is, the molar ratio of dimethylamine to acetic acid is at least 1.01, more preferably 1.01 to 1.5, more preferably 1.01 to 1.20.
반응 온도는 특히 제한되지 않지만, 바람직하게는 30 내지 60℃이다.The reaction temperature is not particularly limited, but is preferably 30 to 60 ° C.
본 발명의 공정중 아미드화 반응 단계에서, 상기 언급된 중화 반응 단계에서 수득된 반응 생성액은 가압하에 아미드화 반응을 거친다. 바람직하게는, 중화 반응단계에서 수득된 반응 생성액은 중화 반응용기로부터 빼내고, 빼낸 반응생성액에 디메틸아민을 더 첨가하고, 수득한 혼합물을 가압하에 아미드화 반응을 시킨다.In the in-process amidation step of the present invention, the reaction product liquid obtained in the above-mentioned neutralization step is subjected to amidation under pressure. Preferably, the reaction product liquid obtained in the neutralization reaction step is taken out from the neutralization reaction vessel, dimethylamine is further added to the taken-out reaction product liquid, and the obtained mixture is subjected to an amidation reaction under pressure.
아미드화 반응용기로 공급시, 상기 언급된 중화 반응 단계에서 수득된 반응 생성액과 디메틸아민은 동시에 아미드화 반응용기에 공급하거나, 혹은 중화 반응 단계에서 수득한 반응생성액을 먼저 공급하고, 이후에 거기에 디메틸포름아미드를 공급할수 있다. 첨가되는 디메틸아민은 액체 또는 기체의 형태이다. 첨가되는 디메틸아민의 양은 중화 반응단계에 충전되는 아세트산에 대한 몰비로서, 0.1 내지 5, 바람직하게는 0.2 내지 2, 더욱 바람직하게는 0.5 내지 1이다.When supplied to the amidation reaction vessel, the reaction product and dimethylamine obtained in the above-mentioned neutralization reaction step are simultaneously supplied to the amidation reaction vessel, or the reaction product obtained in the neutralization reaction step is first supplied, and then Dimethylformamide can be supplied there. The dimethylamine added is in the form of a liquid or gas. The amount of dimethylamine added is 0.1 to 5, preferably 0.2 to 2, more preferably 0.5 to 1 as the molar ratio to acetic acid charged in the neutralization step.
디메틸아민과 중화 반응단계에서 수득된 반응생성액을 아미드화 반응용기에 공급한후, 수득한 혼합물을 100 내지 300℃, 바람직하게는 150 내지 250℃의 반응온도와 0.1 내지 5 MPa, 바람직하게는 1 내지 3 MPa의 반응압력에서 1 내지 2시간동안 반응시킨다.After supplying the reaction product obtained in the neutralization reaction step with dimethylamine to the amidation reaction vessel, the resulting mixture is reacted with a reaction temperature of 100 to 300 ℃, preferably 150 to 250 ℃ and 0.1 to 5 MPa, preferably The reaction is carried out at a reaction pressure of 1 to 3 MPa for 1 to 2 hours.
고압반응기와 같은 꽉 밀폐된 아미드화 반응용기를 사용하여 소정의 반응압력을 유지하고, 상기 언급된 반응온도로 반응액을 가열한다.A tightly sealed amidation reaction vessel such as a high pressure reactor is used to maintain a predetermined reaction pressure, and the reaction solution is heated to the above-mentioned reaction temperature.
아미드화 반응이 완결된 후, 과량의 디메틸아민을 미반응물의 기체형태로 컬럼의 상부에서 회수할수 있다. 압력을 방출한후, 주성분으로써 디메틸아세트아미드를 함유한 액체를 칼럼 바닥에서 회수할수 있다.After the amidation reaction is complete, excess dimethylamine can be recovered at the top of the column in the form of a gas of unreacted material. After releasing the pressure, a liquid containing dimethylacetamide as the main component can be recovered at the column bottom.
촉매는 본 발명의 아미드화 반응단계에서 사용할수 있다. 촉매의 예로는 몰리브덴 옥사이드 및 실리코몰리브덴산과 같은 몰리브덴산 화합물, 텅스텐 트리옥사이드 및 포스포텅스텐 산과 같은 텅스텐산, 그리고 나트륨 메타바나데이트를 포함한다.The catalyst can be used in the amidation reaction step of the present invention. Examples of catalysts include molybdate compounds such as molybdenum oxide and silicomolybdic acid, tungstic acids such as tungsten trioxide and phosphotungstic acid, and sodium metavanadate.
본 발명은 하기 실시예를 참고로 더욱 상세하게 기술되지만, 이러한 실시예로만 본 발명이 한정되는 것이 아니다.The invention is described in more detail with reference to the following examples, but the invention is not limited to these examples.
실시예 1Example 1
교반장치와 환류 냉각기가 설치된 500 ml 분리가능한 플라스크에 아세트산 120 g(2.0 몰)을 채운 다음, 냉각하에 디메틸아민 92.0 g(2.04 몰)로 중화시킨다.A 500 ml separable flask equipped with a stirrer and a reflux condenser is charged with 120 g (2.0 moles) of acetic acid and then neutralized with 92.0 g (2.04 moles) of dimethylamine under cooling.
전체 수득한 중화액을 가열기와 교반장치가 설치된 500 ml 고압반응기에 이송한다. 고압 반응기를 닫고, 기체 공급라인을 통해 디메틸아민 45 g(1 몰)을 채운다음, 고압 반응기를 꽉 밀폐한다. 수득한 혼합물을 교반하에 170℃와 2 MPa의 최대 압력에서 1시간동안 반응시킨다. 반응 수율은 86.5%이다. 실온으로 냉각후, 과량의 디메틸아민을 회수하고, 반응액 220.7 g을 회수한다. (아세트산 기준으로) 반응액중의 디메틸아세트아미드의 농도는 58.7%이고, 반응수율은 86.0%이다.The obtained neutralized liquid is transferred to a 500 ml high pressure reactor equipped with a heater and a stirring device. Close the high pressure reactor, fill 45 g (1 mole) of dimethylamine through the gas feed line, and close the high pressure reactor tightly. The resulting mixture is reacted under stirring at 170 ° C. and a maximum pressure of 2 MPa for 1 hour. The reaction yield is 86.5%. After cooling to room temperature, excess dimethylamine is recovered and 220.7 g of the reaction solution is recovered. The concentration of dimethylacetamide in the reaction solution (based on acetic acid) is 58.7%, and the reaction yield is 86.0%.
비교예 1Comparative Example 1
교반장치와 환류 냉각기가 설치된 500 ml 분리가능한 플라스크에 아세트산 120 g(2.0 몰)을 채운 다음, 냉각하에 디메틸아민 92.0 g(2.04 몰)로 중화시킨다.A 500 ml separable flask equipped with a stirrer and a reflux condenser is charged with 120 g (2.0 moles) of acetic acid and then neutralized with 92.0 g (2.04 moles) of dimethylamine under cooling.
수득한 중화액을 이송하지 않고 그대로 120℃의 반응온도와 상압에서 교반하에 1시간동안 반응시킨다. 반응 결과, 반응 수율은 32%이고, 5시간후 반응수율은 55%, 20시간후 반응수율은 69%이다.The obtained neutralized liquid is reacted for 1 hour under stirring at a reaction temperature of 120 ° C. and normal pressure without being transferred. As a result of the reaction, the reaction yield was 32%, the reaction yield was 55% after 5 hours, and the reaction yield was 69% after 20 hours.
비교예 2Comparative Example 2
형성된 물을 증류제거하는 장치를 분리가능한 플라스크에 부착하고, 형성된 물을 계 밖으로 배출하면서, 150℃의 반응온도에서 1시간동안 반응을 수행하는 것을 제외하고는 비교예 1과 동일한 절차에 따랐다. 반응 수율은 46%이다. 5시간후 반응수율은 82%, 10시간후 반응수율은 95%이다.An apparatus for distilling off the formed water was attached to the detachable flask, and the same procedure as in Comparative Example 1 was followed except that the reaction was carried out for 1 hour at a reaction temperature of 150 ° C while the formed water was discharged out of the system. The reaction yield is 46%. The reaction yield after 5 hours is 82%, after 10 hours the reaction yield is 95%.
실시예 2Example 2
고압 반응기에 촉매로서 MoO30.6 g을 첨가하고, 150 내지 160℃에서 교반하에 반응을 수행하는 것을 제외하고는 실시예 1과 동일한 절차에 따랐다. 1시간후 반응 수율은 88.1%이고, 10시간후 반응수율은 94.5%이다.0.6 g of MoO 3 was added as a catalyst to the high pressure reactor and the same procedure as in Example 1 was followed except that the reaction was carried out under stirring at 150 to 160 ° C. The reaction yield is 88.1% after 1 hour, and 94.5% after 10 hours.
실시예 3Example 3
고압 반응기에 촉매로서 WO30.6 g을 첨가하고, 1.7 MPa의 최대 압력과 150 내지 160℃에서 교반하에 반응을 수행하는 것을 제외하고는 실시예 1과 동일한 절차에 따랐다. 1시간후 반응 수율은 88.0%이다.The same procedure as in Example 1 was followed except that 0.6 g of WO 3 as catalyst was added to the high pressure reactor and the reaction was carried out under stirring at 150 to 160 ° C. with a maximum pressure of 1.7 MPa. The reaction yield after 8 hours is 88.0%.
실시예 4Example 4
고압 반응기에 촉매로서 NaVO30.6 g을 첨가하고, 1.7 MPa의 최대 압력과 150 내지 160℃에서 교반하에 반응을 수행하는 것을 제외하고는 실시예 1과 동일한 절차에 따랐다. 1시간후 반응 수율은 87.3%이다.The same procedure as in Example 1 was followed except that 0.6 g of NaVO 3 as catalyst was added to the high pressure reactor and the reaction was carried out under stirring at 150-160 ° C. with a maximum pressure of 1.7 MPa. The reaction yield after 1 hour is 87.3%.
비교예 3Comparative Example 3
분리가능한 플라스크에 촉매로서 MoO30.6 g을 첨가하고, 반응을 수행하는 것을 제외하고는 비교예 1과 동일한 절차에 따랐다. 반응 수율은 45%이다. 5시간후 반응수율은 69%, 10시간후 반응수율은 79%이다.0.6 g of MoO 3 was added as a catalyst to the detachable flask and the same procedure as in Comparative Example 1 was followed except that the reaction was carried out. The reaction yield is 45%. The reaction yield was 69% after 5 hours and 79% after 10 hours.
비교예 4Comparative Example 4
분리가능한 플라스크에 촉매로서 MoO30.6 g을 첨가하고, 반응을 수행하는 것을 제외하고는 비교예 2와 동일한 절차에 따랐다. 반응 수율은 82%이다. 5시간후 반응수율은 94%, 10시간후 반응수율은 94%이다.0.6 g of MoO 3 was added as a catalyst to the detachable flask and the same procedure as in Comparative Example 2 was followed except that the reaction was carried out. The reaction yield is 82%. The reaction yield was 94% after 5 hours and the reaction yield was 94% after 10 hours.
상기에서 살펴본 바와 같이, 상압에서 아세트산을 디메틸아민으로 중화시킨후, 수득한 생성물을 가압하에 아미드화 반응시키고, 그리고 아미드화 반응단계에서 추가로 디메틸아민을 첨가한후, 수득한 혼합물을 가압하에 아미드화 반응시킴으로써, 불순물 함량이 낮은 디메틸아세트아미드를 고수율로 제조할수 있다.As described above, after acetic acid was neutralized with dimethylamine at atmospheric pressure, the obtained product was subjected to amidation under pressure, and further dimethylamine was added in the amidation reaction step, and then the obtained mixture was pressurized under amide. By the oxidization reaction, dimethylacetamide having a low impurity content can be produced in high yield.
디메틸아세트아미드는 용매로서, 그리고 유기합성 및 약품 등의 생원료으로 산업적으로 유용한 물질이다.Dimethylacetamide is an industrially useful material as a solvent and as a raw material for organic synthesis and medicine.
Claims (4)
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP98-123853 | 1998-04-20 | ||
| JP12385398 | 1998-04-20 | ||
| PCT/JP1999/002070 WO1999054281A1 (en) | 1998-04-20 | 1999-04-19 | Process for producing dimethylacetamide |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| KR20010042773A true KR20010042773A (en) | 2001-05-25 |
Family
ID=14871024
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| KR1020007011509A KR20010042773A (en) | 1998-04-20 | 1999-04-19 | Process for producing dimethylacetamide |
Country Status (4)
| Country | Link |
|---|---|
| KR (1) | KR20010042773A (en) |
| CN (1) | CN1147464C (en) |
| CA (1) | CA2329241A1 (en) |
| WO (1) | WO1999054281A1 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100313669B1 (en) * | 1999-10-14 | 2001-11-15 | 박영구 | Process for preparing N,N- dimethylacetamide |
| CN1325467C (en) * | 2004-08-26 | 2007-07-11 | 西南化工研究设计院 | Technological process of synthesizing dimethyl acetylamide with methyl acetate and dimethylamine |
| CN100420668C (en) * | 2005-12-29 | 2008-09-24 | 西南化工研究设计院 | Process for synthesizing dimethylacetamide by ethyl acetate and dimethylamine |
| CN100537521C (en) * | 2006-06-23 | 2009-09-09 | 中国石油天然气集团公司 | Method for synthesizing N,N dimethyl acetamide in high purity |
| CN106563438B (en) * | 2016-10-12 | 2020-01-03 | 中海油天津化工研究设计院有限公司 | Catalyst for synthesizing amide and method for synthesizing N, N-dimethylpropionamide |
| CN112341353B (en) * | 2020-11-05 | 2022-11-25 | 广州市荔盛化学品有限公司 | Propyl betaine and preparation method thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5382716A (en) * | 1976-12-27 | 1978-07-21 | Shiyosutokinsukii Zabuodo Himi | Process for preparing dimethylacetamide |
| DE4432540A1 (en) * | 1994-09-13 | 1995-03-02 | Thalmann & Kunde Ohg | Process for the preparation of N,N-dimethylcarboxamides |
-
1999
- 1999-04-19 CN CNB99805285XA patent/CN1147464C/en not_active Expired - Lifetime
- 1999-04-19 CA CA002329241A patent/CA2329241A1/en not_active Abandoned
- 1999-04-19 KR KR1020007011509A patent/KR20010042773A/en not_active Application Discontinuation
- 1999-04-19 WO PCT/JP1999/002070 patent/WO1999054281A1/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| CA2329241A1 (en) | 1999-10-28 |
| WO1999054281A1 (en) | 1999-10-28 |
| CN1147464C (en) | 2004-04-28 |
| CN1298382A (en) | 2001-06-06 |
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