KR20020051353A - New manufacturing of 2-halopyridine N-oxide derivatives - Google Patents
New manufacturing of 2-halopyridine N-oxide derivatives Download PDFInfo
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- C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
- C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
- C07D213/89—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members with hetero atoms directly attached to the ring nitrogen atom
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- C—CHEMISTRY; METALLURGY
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- C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
- C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
- C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
- C07D213/60—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
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Abstract
Description
본 발명은 항균제 및 곰팡이 방지제로 널리 사용되는 피리치온계 항균제의 핵심중간체로 작용하는 2-할로피리딘 N-옥사이드 유도체의 제조방법에 관한 것이다.The present invention relates to a method for preparing a 2-halopyridine N-oxide derivative that acts as a core intermediate of pyrithione-based antimicrobial agents widely used as antibacterial and antifungal agents.
종래 기술로는 2-할로피리딘을 출발물질로 하여 초산과 과산화수소를 반응중에 첨가하여 과산화초산이 형성되도록 한 후 2-할로피리딘 N-옥사이드를 제조하는 방법이 있다.In the prior art, 2-halopyridine N-oxide is prepared by adding acetic acid and hydrogen peroxide during the reaction using 2-halopyridine as a starting material to form acetic acid.
미국특허 2,745,826호에는 산화제로 사용가능한 과산화초산을 제조하여 2-할로피리딘에 2당량 이상 반응시켜 피리딘 N-옥사이드를 제조하는 방법이 소개되어 있다. 그러나 이 방법은 반응시간이 10시간 이상으로 길고 수율이 50%대로 낮으며,산화제의 과량 사용으로 인해 중화 처리시 과량의 염기사용으로 낮은 생산성을 유발한다.U.S. Patent No. 2,745,826 discloses a process for preparing pyridine N-oxide by preparing acetic acid which can be used as an oxidizing agent and reacting with 2-halopyridine for at least 2 equivalents. However, this method has a long reaction time of more than 10 hours, a low yield of 50%, and low productivity due to the use of excess base in the neutralization treatment due to the excessive use of the oxidizing agent.
또한, 미국특허 2,951,844호에서는 산화제인 과산화초산을 미리 만듦에 있어서 촉매로 황산을 사용하였고, 미국특허 4,585,871호에서는 2-할로피리딘 존재하에 반응을 진행하면서 황산 및 황산화물을 촉매로 사용하였다. 그러나, 과산화초산의 불안정성으로 인하여 산화제를 미리 제조하더라도 저장하는데 문제점이 있으며 황산 및 황산화물을 사용하는 방법은 반응시간을 줄이고 과산화수소의 사용량을 다소 줄여주는 효과는 있지만 강산을 촉매로 사용하기 때문에 중화시 염기의 사용량이 많아져서 제조 효율이 떨어지게 되고 반응 색상을 어둡게 하는 단점이 있으며 특히, 상기 방법들 모두 수율이 50%대로 낮다는 단점이 있다.In US Pat. No. 2,951,844, sulfuric acid was used as a catalyst for pre-forming acetic acid peroxide, and in US Pat. No. 4,585,871, sulfuric acid and sulfur oxide were used as catalysts in the presence of 2-halopyridine. However, due to the instability of acetic acid peroxide, there is a problem in storing the oxidizing agent even if it is prepared in advance.However, the method of using sulfuric acid and sulfur oxides reduces the reaction time and slightly reduces the amount of hydrogen peroxide. Since the amount of the base used increases, the production efficiency is lowered and the reaction color is darkened. In particular, all of the above methods have a low yield of 50%.
또한 피리딘 N-옥사이드를 제조하기 위한 과산화초산의 다른 제조방법으로는, 과산화수소와 벤조니트릴이나 아세토니트릴을 가성소다와 함께 사용하는 방법(J. Org. Chem., 1961, Vol 26, p659, p3669) 및 과산화수소와 개미산을 사용하는 방법(J. Am. Chem. Soc., 1955, Vol 77, p4846)이 있으나 일반적으로 반응성이 30% 이하로 떨어지게 되어 상업적인 방법으로는 적합하지 않다.In addition, as another method for preparing acetic acid for preparing pyridine N-oxide, hydrogen peroxide and a method of using benzonitrile or acetonitrile together with caustic soda (J. Org. Chem., 1961, Vol 26, p659, p3669) And a method using hydrogen peroxide and formic acid (J. Am. Chem. Soc., 1955, Vol 77, p4846), but the reactivity is generally less than 30%, which is not suitable for commercial methods.
출발물질이 전혀 다른 방법으로, 캐나다특허 841632호에 2-할로피리딘이 아닌 피리딘 N-옥사이드를 출발물질로하여 2번 위치에 할로겐을 도입하는 방법이 소개되어 있으나, 알칼리금속 히드리드, 알칼리금속의 메톡사이드, 에톡사이드 등의 강염기를 사용하여 피리딘 N-옥사이드로부터 2-할로피리딘 N-옥사이드를 합성하는 방법이지만, 강염기가 출발물질 대비 1당량 이상 사용되며 염기의 회수가 거의 불가능하고 가격면에서 불리하기 때문에 초산, 과산화수소를 사용하는 방법보다 경제적이지 못하다.As a completely different method of starting materials, Canadian Patent 841632 introduces a method of introducing halogen at position 2 using pyridine N-oxide instead of 2-halopyridine. It is a method of synthesizing 2-halopyridine N-oxide from pyridine N-oxide using strong base such as methoxide, ethoxide, etc., but strong base is used more than 1 equivalent compared to starting material and recovery of base is almost impossible and disadvantageous in price This is less economical than using acetic acid and hydrogen peroxide.
본 발명자들은 종래기술의 문제점을 해결하고자 연구를 거듭한 결과, 2-할로피리딘을 산화철(Ⅲ) 화합물 촉매하에서 반응시킴으로서 반응도를 높이고, 2-할로피리딘 N-옥사이드의 열 또는 과산화수소의 라디칼 형성에 따른 분해를 최소화하여 고수율의 2-할로피리딘 N-옥사이드을 얻을 수 있다는 것을 발견하고 본 발명을 완성하였다.The present inventors have conducted studies to solve the problems of the prior art, and as a result, by reacting 2-halopyridine under a catalyst of iron (III) oxide, the reactivity is increased, and according to the heat of 2-halopyridine N-oxide or radical formation of hydrogen peroxide The present invention was completed by discovering that minimization of decomposition can yield high yields of 2-halopyridine N-oxide.
본 발명은 2-할로피리딘 N-옥사이드의 개선된 제조방법을 제공하는 것을 그 목적으로 한다.It is an object of the present invention to provide an improved process for the preparation of 2-halopyridine N-oxides.
본 발명은 화학식 (1)로 나타내어지는 2-할로피리딘을 산화철(Ⅲ)화합물을 촉매로 하여 과산화수소와 반응시킴으로서 화학식(2)로 나타내어지는 2-할로피리딘 N-옥사이드를 제조하는 방법에 관한 것이다.The present invention relates to a method for producing 2-halopyridine N-oxide represented by the formula (2) by reacting 2-halopyridine represented by the formula (1) with hydrogen peroxide using a catalyst of iron (III) oxide.
본 발명에서의 2-할로피리딘 N-옥사이드의 제조방법은 하기의 반응식 (2)와 같다.Method for producing 2-halopyridine N-oxide in the present invention is shown in the following scheme (2).
화학식 1 화학식 2Chemical Formula 1 Chemical Formula 2
여기서 X는 할로겐 원소, 즉 플루오르, 염소, 브롬 및 요오드 등이며, 촉매는 산화철(Ⅲ) 화합물이다.Wherein X is a halogen element, ie fluorine, chlorine, bromine and iodine, and the catalyst is an iron (III) oxide compound.
상기 반응에 사용되는 촉매는 산화철(Ⅲ) 화합물로서 예를 들어 FeCl3, Fe2(SO4)3및 Fe(ClO4)3에서 선택되는 것이 바람직하다. 그 사용량은 화학식 (1)의 2-할로피리딘에 대해 0.1~ 1.0 몰을 사용하는 것이 바람직하며, 더욱 바람직하게는 0.1~ 0.5몰이다. 촉매 사용량이 많을 경우, 제품이 분해되어 수율이 최고 20% 이상 감소할 수 있다.The catalyst used in the reaction is preferably selected from, for example, FeCl 3 , Fe 2 (SO 4 ) 3 and Fe (ClO 4 ) 3 as the iron (III) oxide compound. It is preferable to use 0.1-1.0 mol with respect to the 2-halopyridine of General formula (1), More preferably, it is 0.1-0.5 mol. If the amount of catalyst used is high, the product may be decomposed and the yield may be reduced by up to 20% or more.
상기 반응의 온도는 50~ 90℃가 바람직하며, 60~ 85℃가 더욱 바람직하다.50-90 degreeC is preferable and, as for the temperature of the said reaction, 60-85 degreeC is more preferable.
과산화수소는 30~ 70% 수용액으로, 그 양은 화학식 (1)의 화합물에 대해 1.0~ 5.0 몰을 사용하는 것이 바람직하며, 더욱 바람직하게는 1.0~ 3.0몰이다. 과산화수소수의 양이 많거나 적을 경우 수율이 감소할 수 있다.Hydrogen peroxide is a 30-70% aqueous solution, It is preferable to use 1.0-5.0 mol with respect to the compound of General formula (1), More preferably, it is 1.0-3.0 mol. If the amount of hydrogen peroxide is high or low, the yield may decrease.
반응용매는 사용하지 않으며, 반응이 완결되면 남아있는 과산화수소수 또는 퍼옥사이드는 산을 사용하여 제거한다. 산을 사용하여 제거함으로서 고순도의 제품을 얻을 수 있다.The reaction solvent is not used. When the reaction is completed, the remaining hydrogen peroxide or peroxide is removed using an acid. By removing with acid, a high purity product can be obtained.
이하 실시예를 들어 본 발명의 내용을 구체적으로 설명하나 본 발명이 이에 한정되는 것은 아니다.Hereinafter, the content of the present invention will be described in detail with reference to the following examples, but the present invention is not limited thereto.
실시예 1. 2-클로로피리딘 N-옥사이드의 제조Example 1.Preparation of 2-chloropyridine N-oxide
1ℓ둥근바닥플라스크에 2-염화피리딘 113g(1.0몰)과 삼염화철 63g(0.5몰)을 투입하고 교반하였다. 온도를 60℃까지 승온한 후 50% 과산화수소수 204g(3.0몰)을 80℃이하에서 적가하였다. 적가완료 후 10시간동안 반응시켰다.Into a 1L round bottom flask, 113 g (1.0 mole) of 2-chloropyridine and 63 g (0.5 mole) of iron trichloride were added and stirred. After the temperature was raised to 60 ° C., 204 g (3.0 mol) of 50% hydrogen peroxide solution was added dropwise at 80 ° C. or lower. After completion of the dropwise addition, reaction was carried out for 10 hours.
HPLC분석 결과 반응이 75% 진행되었다. 반응완결 후 동일 온도에서 증류하여 반응후 남은 2-염화피리딘을 회수하고, 아세톤을 투입하여 여과한 후 용매를 증류하여 상기의 목적화합물 92g을 얻었다. 염화피리딘을 회수한 것은 28g으로 회수율이 99%이고 회수한 것을 고려한 수율은 95%이었고 갈색고체이었으며 HPLC분석에 의한 순도는 99.3%이었다.HPLC analysis showed a 75% reaction. After completion of the reaction, the reaction mixture was distilled at the same temperature to recover the remaining 2-chloropyridine, acetone was added and filtered, and the solvent was distilled off to obtain 92 g of the target compound. The recovery of pyridine chloride was 28 g, the yield was 99%, the yield was 95%, brown solid, and the purity by HPLC analysis was 99.3%.
실시예 2. 2-클로로피리딘 N-옥사이드염산염의 제조Example 2. Preparation of 2-chloropyridine N-oxide Hydrochloride
1ℓ둥근플라스크에 2-염화피리딘 113g(1.0몰)과 황화철수화물 49g(0.1몰)과 50% 과산화수소수 136g(2.0몰)을 투입하고 70℃까지 승온하여 12시간 동안 반응시켰다. HPLC 분석에 의한 순도는 99%이었다113 g (1.0 mol) of 2-chloropyridine, 49 g (0.1 mol) of ferric sulfide, and 136 g (2.0 mol) of 50% hydrogen peroxide were added to a 1 L round flask, and the reaction mixture was heated to 70 ° C. for 12 hours. Purity by HPLC analysis was 99%
비교예 1.Comparative Example 1.
1ℓ 둥근바닥플라스크에 2-염화피리딘 113g(1.0몰), 초산 60g(1.0몰)을 넣은 뒤, 70℃ 항온조에서 교반하면서 50% 과산화수소 100g(1.5몰)을 적가 장치를 이용하여 2시간에 걸쳐 적가하였다. 적가를 마친 반응액을 70℃로 유지하면서 계속 교반하면서 과산화수소 투입 후 30분마다 HPLC로 반응 진행사항을 확인하였다. HPLC로 반응이 더이상 진행되지 않을 때를 반응완료 시점으로 하였다.Into a 1L round bottom flask, 113 g (1.0 mole) of 2-chloropyridine and 60 g (1.0 mole) of acetic acid were added, and then 100 g (1.5 mole) of 50% hydrogen peroxide was added dropwise over 2 hours while stirring in a 70 ° C. constant temperature bath. It was. After the dropwise addition, the reaction solution was maintained at 70 ° C. while stirring was continued to check the progress of the reaction every 30 minutes after adding hydrogen peroxide. When the reaction no longer proceeded by HPLC, the reaction was completed.
반응이 30%정도 진행되었다.The reaction proceeded about 30%.
비교예 2.Comparative Example 2.
1ℓ 둥근바닥플라스크에 2-염화피리딘 113g(1.0몰), 초산 60g(1.0몰)을 넣은 뒤, 촉매로서 황산을 0.04몰을 투입하고 70℃ 항온조에서 교반하면서 50% 과산화수소 100g(1.5몰)을 적가 장치를 이용하여 2시간에 걸쳐 적가하였다. 적가를 마친 반응액을 70℃로 유지하면서 계속 교반하면서 과산화수소 투입 후 30분마다 HPLC로 반응 진행사항을 확인하였다.Into a 1L round bottom flask, 113 g (1.0 mole) of 2-chloropyridine and 60 g (1.0 mole) of acetic acid were added. Then, 0.04 mole of sulfuric acid was added as a catalyst and 100 g (1.5 mole) of 50% hydrogen peroxide was added dropwise while stirring in a 70 ° C. constant temperature bath. It was added dropwise over 2 hours using the apparatus. After the dropwise addition, the reaction solution was maintained at 70 ° C. while stirring was continued to check the progress of the reaction every 30 minutes after adding hydrogen peroxide.
반응이 46%정도 진행되었고 더 이상 진행되지 않았다.The reaction proceeded by 46% and no longer.
비교예 3.Comparative Example 3.
1ℓ둥근바닥플라스크에 2- 염화피리딘 113g(1.0몰), 초산 60g(1.0몰)을 넣은 뒤, 촉매로서 황산을 4.0g(0.04몰)을 넣고 70℃ 항온조에서 교반하면서 50% 과산화수소 136g(2.5몰당량)을 적가 장치를 이용하여 2시간에 걸쳐 적가하였다. 적가를 마친 반응액을 70℃로 유지하면서 계속 교반하면서 과산화수소를 투입하여 30분마다 HPLC로 반응 진행사항을 확인하였다.Into a 1L round bottom flask, 113 g (1.0 mol) of 2-chloropyridine and 60 g (1.0 mol) of acetic acid were added, followed by 4.0 g (0.04 mol) of sulfuric acid as a catalyst and 136 g (2.5 mol) of 50% hydrogen peroxide while stirring in a 70 ° C thermostat. Equivalent) was added dropwise over 2 hours using the dropping apparatus. While maintaining the reaction solution at the dropwise addition, the hydrogen peroxide was added while the stirring was continued, and the reaction progress was checked by HPLC every 30 minutes.
반응이 50% 정도 진행된 후, 더 이상 진행되지 않았다.After about 50% of the reaction, no further progress was made.
비교예 4.Comparative Example 4.
1ℓ둥근바닥플라스크에 2-염화피리딘 113g(1.0몰), 초산 120g(1.0몰), 촉매로서 황산을 4.0g(0.04몰)을 넣고, 70℃ 항온조에서 교반하면서 50% 과산화수소 100g(1.5몰)을 적가 장치를 이용하여 2시간에 걸쳐 적가하였다. 적가를 마친 반응액을 70℃로 유지하면서 계속 교반하면서 과산화수소를 투입하여 30분마다 HPLC로 반응 진행사항을 확인하였다.Into a 1 liter round bottom flask, 113 g (1.0 mole) of 2-chloropyridine, 120 g (1.0 mole) of acetic acid, 4.0 g (0.04 mole) of sulfuric acid as a catalyst, and 100 g (1.5 mole) of 50% hydrogen peroxide while stirring in a 70 ° C. thermostatic bath. It was added dropwise over 2 hours using the dropping device. While maintaining the reaction solution at the dropwise addition, the hydrogen peroxide was added while the stirring was continued, and the reaction progress was checked by HPLC every 30 minutes.
반응이 49%까지 진행된 후 더 이상 진행되지 않았다.The reaction proceeded up to 49% and no longer.
본 발명의 제조방법으로 2-할로피리딘 N-옥사이드 제조과정에서의 2-할로피리딘 N-옥사이드의 열 또는 과산화수소의 라디칼 형성에 따른 분해를 최소화하여 고수율의 2-할로피리딘 N-옥사이드를 얻을 수 있으며, 또한 본 발명으로 2-할로피리딘 N-옥사이드의 상업적 생산이 용이하다.In the manufacturing method of the present invention, high yield of 2-halopyridine N-oxide can be obtained by minimizing decomposition of the heat of 2-halopyridine N-oxide or radical formation of hydrogen peroxide in the process of preparing 2-halopyridine N-oxide. In addition, the present invention facilitates the commercial production of 2-halopyridine N-oxide.
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| KR100830557B1 (en) * | 2002-01-02 | 2008-05-21 | 에스케이케미칼주식회사 | Preparation method of pyrithione salt |
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