JPH04507406A - Production method of 2,6-dichloroquinoxaline - Google Patents
Production method of 2,6-dichloroquinoxalineInfo
- Publication number
- JPH04507406A JPH04507406A JP51067990A JP51067990A JPH04507406A JP H04507406 A JPH04507406 A JP H04507406A JP 51067990 A JP51067990 A JP 51067990A JP 51067990 A JP51067990 A JP 51067990A JP H04507406 A JPH04507406 A JP H04507406A
- Authority
- JP
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- Prior art keywords
- chloro
- hydroxyquinoxaline
- oxide
- solution
- sodium salt
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D241/00—Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings
- C07D241/36—Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings condensed with carbocyclic rings or ring systems
- C07D241/50—Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings condensed with carbocyclic rings or ring systems with hetero atoms directly attached to ring nitrogen atoms
- C07D241/52—Oxygen atoms
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D241/00—Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings
- C07D241/36—Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings condensed with carbocyclic rings or ring systems
- C07D241/38—Heterocyclic compounds containing 1,4-diazine or hydrogenated 1,4-diazine rings condensed with carbocyclic rings or ring systems with only hydrogen or carbon atoms directly attached to the ring nitrogen atoms
- C07D241/40—Benzopyrazines
- C07D241/44—Benzopyrazines 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 carbon atoms of the hetero ring
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Plural Heterocyclic Compounds (AREA)
Abstract
(57)【要約】本公報は電子出願前の出願データであるため要約のデータは記録されません。 (57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.
Description
【発明の詳細な説明】 2.6−ジクロルキノキサリンの製法 本発明の対象は、技術水準に比較して、6−クロル−2−ヒドロキシキノキサリ ン−N−オキシドの6−クロル−2−ヒドロキシキノキサリンへの還元、そのナ トリウム塩の晶出、水の除去及びそれ自体公知の方法での塩素化による2、6− ジクロルキノキサリンの改善された製法である。[Detailed description of the invention] 2. Process for producing 6-dichloroquinoxaline The object of the invention is that, compared to the state of the art, 6-chloro-2-hydroxyquinoxalin Reduction of N-N-oxide to 6-chloro-2-hydroxyquinoxaline, its Na 2,6- by crystallization of the thorium salt, removal of water and chlorination in a manner known per se. This is an improved method for producing dichloroquinoxaline.
2.6−ジクロルキノキサリンは植物保護剤を製造するための重要な前駆物質で ある(欧州特許第276741A号明細書、ドイツ特許出願公開第300477 0号公報)。この場合2.6−ジクロルキノキサリンを純粋な形で使用すること が重要である。2,6−ジクロルキノキサリンを製造するだめの全ての公知方法 (Houben−Weyl、第1巻。2.6-Dichloroquinoxaline is an important precursor for the production of plant protection agents. (European Patent No. 276741A, German Patent Application No. 300477) Publication No. 0). In this case 2,6-dichloroquinoxaline should be used in pure form. is important. All known methods for producing 2,6-dichloroquinoxaline (Houben-Weyl, Vol. 1.
第359頁以下、(1952)、又はOrganikum、ベルリン1976 、 VEBドイツ科学出版社と関連した、欧州特許第0295815号明細書; 欧州特許第0295797号明細書;米国特許第4636562号明細書; 5 akata 及びその他の者、 Heterocycles 23゜143、2 025 (1985) ; ドイツ特許第3901406号明細書;欧州特許出 願環89106784、5号公報参照)の場合、品質か植物保護剤及び他の生成 物に直接さらに加工するために十分でない生成物が得られ、それゆえ公知方法に より得られる2、6−ジクロルキノキサリンはさらに加工する前に経費のかさむ 精製法に付されねばならない。それゆえ2,6〜ジクロルキノキサリンを、経費 のかさむ精製操作なしに所望の生成物に直接さらに加工することができる様に高 い純度で得られる製法をめる要求があった。Pages 359 et seq. (1952), or Organikum, Berlin 1976 , European Patent No. 0295815, associated with VEB German Scientific Publishers; European Patent No. 0295797; US Patent No. 4636562; 5 akata and others, Heterocycles 23゜143, 2 025 (1985); German Patent No. 3901406; European Patent Application 89106784, see Publication No. 5), quality or plant protection agents and other production A product is obtained which is not sufficient for further processing directly into a product and is therefore not suitable for the known method. The 2,6-dichloroquinoxaline obtained is expensive before further processing. It must be subjected to a purification process. Therefore, 2,6-dichloroquinoxaline is high purity so that it can be further processed directly to the desired product without extensive purification operations. There was a demand for a manufacturing method that would provide high purity.
驚くべきことに本発明は、6−クロル−2−ヒドロキシキノキサリン−N−オキ シドを水性水酸化ナトリウム溶液中で使用される6−クロル−2−ヒドロキシキ ノキサリン−N−オキシドに対し約0.001乃至約0.5モルパーセント、好 ましくは0.01乃至約0.05モルパーセントの白金一般触媒の存在下約20 乃至約120’C1好ましくは約60乃至約100℃の温度及び約1乃至約10 0バール、好ましくは約5乃至約20バールの水素圧において水素添加し、その 際使用される6〜クロル−2−ヒドロキシキノキサリン−N−オキシドに対し約 1乃至約3当量の水酸化ナトリウムを存在させ、熱い溶液からの触媒の分離後該 溶液中に溶解した6−クロル−2−ヒドロキシキノキサリンを、約0乃至約20 ”C1好ましくは約5乃至約1o″Cの温度への反応溶液の冷却により、ナトリ ウム塩の形で結晶析出し、不活性溶剤と共に共沸的に乾燥しそしてそれ自体通常 の方法で塩素化剤により塩素化して2.6−ジクロルキノキサリンとすることに よって、2.6−ジクロルキノキサリンを高純度及び同時に良好な収率で製造す ることができることを見出した。Surprisingly, the present invention provides 6-chloro-2-hydroxyquinoxaline-N-ox 6-chloro-2-hydroxy compound used in aqueous sodium hydroxide solution. about 0.001 to about 0.5 mole percent based on noxaline-N-oxide, preferably Preferably in the presence of 0.01 to about 0.05 mole percent platinum general catalyst. a temperature of from about 120' C1 to about 120' C1, preferably from about 60 to about 100'C and from about 1 to about 10 hydrogenation at a hydrogen pressure of 0 bar, preferably from about 5 to about 20 bar; For the 6-chloro-2-hydroxyquinoxaline-N-oxide used in 1 to about 3 equivalents of sodium hydroxide are present and the catalyst is removed after separation from the hot solution. The amount of 6-chloro-2-hydroxyquinoxaline dissolved in the solution is about 0 to about 20 By cooling the reaction solution to a temperature of "C1, preferably from about 5 to about 1o"C, the sodium Crystals precipitate in the form of um salts, dry azeotropically with inert solvents and as such are usually It was chlorinated with a chlorinating agent to produce 2,6-dichloroquinoxaline using the method of Therefore, it is possible to produce 2,6-dichloroquinoxaline with high purity and good yield at the same time. I discovered that it is possible to
本発明による方法に関して詳細には次の様に実施される:通例6−クロルー2− ヒドロキシキノキサリン−N−オキシドを水性水酸化ナトリウム溶液中で約15 乃至約30重量パーセント、好ましくは約20乃至約25重量パーセントの濃度 において懸濁した形で水素添加に付することか合目的である。The process according to the invention is carried out in detail as follows: typically 6-chloro-2- Hydroxyquinoxaline-N-oxide is dissolved in aqueous sodium hydroxide solution for about 15 min. A concentration of from about 30 weight percent, preferably from about 20 to about 25 weight percent. It is expedient to subject it to hydrogenation in suspended form.
接触水素添加は、反応パラメーター次第で、約30分乃至約5時間、通例約1乃 至約3時間を必要とする。Catalytic hydrogenation takes about 30 minutes to about 5 hours, typically about 1 to 5 hours, depending on reaction parameters. It takes about 3 hours.
殻触媒は、通常称される、主として貴金属の単一分布を担体材料粒子内(孔等を 介して)も存する貴金属触媒と異なり、貴金属、例えば白金を微細形で主として 担体材料粒子、例えば活性炭の表面上に分布されている様な水素添加触媒と称さ れる。Shell catalysts are commonly referred to as monodistribution of primarily precious metals within the support material particles (through pores, etc.). Unlike noble metal catalysts, which also exist (via), precious metals, such as platinum, are mainly used in finely divided form. Hydrogenation catalysts such as those distributed on the surface of support material particles, e.g. activated carbon, It will be done.
使用される触媒は、くり返し使用することができる。The catalyst used can be used repeatedly.
水素添加により生成した、6−クロル−2−ヒドロキシキノキサリンのナトリウ ム塩は、反応条件下溶解されておりそして簡単に触媒から分離することができる 。Sodium 6-chloro-2-hydroxyquinoxaline produced by hydrogenation The mu salt is dissolved under the reaction conditions and can be easily separated from the catalyst. .
約O乃至約20°C1好ましくは約5乃至約10°Cへの引き続いての冷却の際 実際上定量的に沈澱する。この様に得られる生成物は優れた品質を有する。Upon subsequent cooling from about 0 to about 20°C, preferably from about 5 to about 10°C It precipitates practically quantitatively. The product thus obtained has excellent quality.
さらに加工するためには、好ましくは水湿潤形で、水と共に共沸体を形成するこ とができる不活性稀釈剤に導入される。適当な稀釈剤としては、例えばベンゼン 、トルエン、キシレン、(全ての異性体及びそれらの混合物)、クメン、クロル ベンゼン、エチルベンゼン、四塩化炭素、トリクロルメタン、シクロヘキサン、 ヘキサン、ヘプタン並びに適当な石油エーテル留分が挙げられる。その場合、含 存する水は共沸的に除去される。For further processing, preferably in water-wet form, it is possible to form an azeotrope with water. It is introduced into an inert diluent that can be used. Suitable diluents include, for example, benzene. , toluene, xylene, (all isomers and mixtures thereof), cumene, chlorine Benzene, ethylbenzene, carbon tetrachloride, trichloromethane, cyclohexane, Mention may be made of hexane, heptane and suitable petroleum ether fractions. In that case, including Any water present is removed azeotropically.
引き続いて通常の塩素化剤、例えば塩化チオニル、五塩化リン、ホスゲン又は、 好ましくはオキシ三塩化リンを用いてそれ自体公知の方法で塩素化される(例え ばHouben−Weyl、第■巻、359頁以下(1952) ; Orga nikum、ベルリン1986゜VEBドッッ科学出版社参照)。Subsequently, customary chlorinating agents such as thionyl chloride, phosphorus pentachloride, phosgene or It is preferably chlorinated using phosphorus oxytrichloride in a manner known per se (e.g. Houben-Weyl, Volume ■, pp. 359 et seq. (1952); Orga Nikum, Berlin 1986゜VEB Dot Science Publishers).
過剰に使用される塩素化剤は分離されそして、再取得可能な稀釈と同様に、別の 混合物に関して使用され得る。The chlorinating agent used in excess is separated and reused as a diluent, as well as a separate Can be used in conjunction with mixtures.
後処理は、常法で行われる。目的生成物、2.6−ジクロルキノキサリンは、必 要な高純度でそしてその上良好な収率で得られる。Work-up is carried out in a conventional manner. The desired product, 2,6-dichloroquinoxaline, is It is obtained in the required high purity and also in good yields.
6−クロル−2−ヒドロキシキノキサリンのナトリウム塩を本発明により実際上 定量的に結晶析出させることができることは、これが単独で加熱状態でも比較的 大なる稀釈状態でも非常に容易に溶解する限りでは驚くべきことと認められる。The sodium salt of 6-chloro-2-hydroxyquinoxaline can be practically used according to the present invention. The fact that it is possible to quantitatively precipitate crystals means that it is relatively easy to precipitate crystals even when heated alone. This is surprising insofar as it is very easily dissolved even in highly diluted conditions.
達成される実際上定量的な、6−クロル−2−ヒドロキシキノキサリンのナトリ ウム塩の結晶析出と関係している極度の精製効果は殊に驚くべきことと評価され るべきである。何となれば中性の6−クロル−2−ヒドロキシキノキサリンの再 結晶は、通常の溶剤中での又高温におけるそのわずかな溶解性及び重要な不純物 との大なる類似性のために、慣用の条件下合成される次の段階物(2,6−ジク ロルキノキサリン)の再結晶と同じくらい少なく十分であるからである。Practically quantitative concentration of 6-chloro-2-hydroxyquinoxaline achieved The extreme purification effect associated with the crystallization of the um salt has been rated as particularly surprising. Should. What happens if neutral 6-chloro-2-hydroxyquinoxaline is recycled? The crystals have a low solubility in common solvents and at high temperatures and significant impurities. The next step synthesized under conventional conditions (2,6-dimethyl) This is because as little as the recrystallization of lorquinoxaline) is sufficient.
本発明による方法の既記の長所のほかに、中間的に生成した6−クロル−2−ヒ ドロキシキノキサリンの中間単離及びこれと関係した中和の省略による全方法の 塩負荷の著しい低減において別の、特に生態学的点からの重要な長所がある。In addition to the already mentioned advantages of the process according to the invention, the intermediately formed 6-chloro-2-hydrocarbon of the entire process by omitting the intermediate isolation of droxyquinoxaline and the associated neutralization. There is another, particularly important advantage from an ecological point of view, in the significant reduction of salt loading.
水素添加段階の最後に高純度及び良好な収率で得られる6−クロル−2−ヒドロ キシキノキサリンはそのまま純粋で得ることが望ましい場合は、6−クロル−2 −ヒドロキシキノキサリンの分離せるナトリウム塩に又は好ましくはこの化合物 の水性溶液への鉱酸、例えば硫酸又は塩酸の添加により簡単に純粋に得ることが できる下記の例により本発明による方法を詳述するが、これにより本発明が限定 されてはならない。6-chloro-2-hydro obtained with high purity and good yield at the end of the hydrogenation step If it is desired to obtain xiquinoxaline in pure form, 6-chloro-2 - a separable sodium salt of hydroxyquinoxaline or preferably this compound; can be easily obtained pure by addition of a mineral acid, such as sulfuric acid or hydrochloric acid, to an aqueous solution of The method according to the invention is illustrated in more detail by the following examples which may be used, but do not limit the invention. must not be done.
例 6−クロル−2−ヒドロキシキノキサリン−N−オキシド593g(1モル)、 工業的に湿潤した形でのナトリウム塩を水757gに懸濁しそして白金殻触媒( タイプ2.5 Pt/C,F 101 KY/W−水約50重量ハーセントヲ含 有す6−(DEG[]5SA) ) 2gの存在下80〜90°Cに加熱しそし て10バールの圧力下1.5時間オートクレーブ中で水素で水素添加した。引き 続いて触媒を80〜90″Cにおいて加圧メツチェ上で分離し、濾液を約5℃に 冷却しそして沈澱を該メツチェ上で濾別した。example 593 g (1 mol) of 6-chloro-2-hydroxyquinoxaline-N-oxide, The sodium salt in industrial wet form was suspended in 757 g of water and the platinum shell catalyst ( Type 2.5 Pt/C, F 101 KY/W - Contains approximately 50% water by weight Heated to 80-90 °C in the presence of 2 g of 6-(DEG[]5SA)) The mixture was hydrogenated with hydrogen in an autoclave for 1.5 hours under a pressure of 10 bar. pull The catalyst was then separated on a pressurized mesh at 80-90"C and the filtrate was heated to approx. 5C. It was cooled and the precipitate was filtered off on the Metsche.
6−クロル−2−ヒドロキシキノキサリン369.5g (0,9モル)が、ナ トリウム塩の形で湿潤生成物として得られた。369.5 g (0.9 mol) of 6-chloro-2-hydroxyquinoxaline was Obtained as a wet product in the form of thorium salt.
異性体のクロルヒドロキシキノキサリンは検出できず、6−クロル−2,3−ヒ ドロキシキノキサリン又はそのナトリウム塩は、最小のこん跡しか検出されなか った(それぞれ)IPLCにより、定量的)。The isomer chlorohydroxyquinoxaline was not detected and 6-chloro-2,3-hyperoxyquinoxaline was detected. Only minimal traces of droxyquinoxaline or its sodium salt have been detected. (quantitatively by IPLC).
ナトリウム塩の乾燥試料は次の分析データを示した:C:42.0%;H:2. 7%; N: 12.0%、 O: 12.9%; C1: 15.2%; N a: 10.2%、純度的 89%(HPLC:外部標準)引き続いて、湿潤し た生成物164.2g (0,4モル)をキシレン約700mj’中に懸濁し、 共沸的に乾燥しそして還流下ヒドロキシ三塩化リン245. O,g(1,、6 モル)を加えた。30分間攪拌した後過剰の塩素化剤を留出し、残留物をキシレ ン約290Tnlで稀釈し、加熱下清澄化しそして水蒸気蒸留により溶剤を除去 した。晶出した生成物を吸引ろ過しそして乾燥させた。A dry sample of the sodium salt showed the following analytical data: C: 42.0%; H: 2. 7%; N: 12.0%, O: 12.9%; C1: 15.2%; N a: 10.2%, purity 89% (HPLC: external standard), subsequently moistened 164.2 g (0.4 mol) of the product obtained were suspended in approximately 700 mj' of xylene, Azeotropically dried and under reflux hydroxyphosphorus trichloride 245. O,g(1,,6 mol) was added. After stirring for 30 minutes, the excess chlorinating agent was distilled off and the residue was diluted with approximately 290 Tnl of water, clarified under heat and removed the solvent by steam distillation. did. The crystallized product was filtered off with suction and dried.
純度97.2%を有する2、6−シクロルキノキサリン72.2gが得られた( HPLC1外部標準)。残余分は、主として無機成分から構成されていた。72.2 g of 2,6-cycloquinoxaline with a purity of 97.2% were obtained ( HPLC1 external standard). The remainder consisted primarily of inorganic components.
2、3.6−ジクロルキノキサリンの含有率: 約0.2% (GLC)異性体 のジクロキノキサリンの含有率、 < 501)pm (GLC)融点、155 乃至158°C 色調−淡ベージュ色の結晶Content of 2,3.6-dichloroquinoxaline: Approximately 0.2% (GLC) isomer Content of dichloroquinoxaline, <501) pm (GLC) melting point, 155 ~158°C Color: light beige crystals
Claims (6)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19893925969 DE3925969A1 (en) | 1989-08-05 | 1989-08-05 | METHOD FOR PRODUCING 2,6-DICHLORCHINOXALINE |
DE3925969.2 | 1989-08-05 |
Publications (1)
Publication Number | Publication Date |
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JPH04507406A true JPH04507406A (en) | 1992-12-24 |
Family
ID=6386594
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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JP51067990A Pending JPH04507406A (en) | 1989-08-05 | 1990-07-16 | Production method of 2,6-dichloroquinoxaline |
Country Status (5)
Country | Link |
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JP (1) | JPH04507406A (en) |
CA (1) | CA2064564A1 (en) |
DE (1) | DE3925969A1 (en) |
IN (1) | IN169080B (en) |
WO (1) | WO1991001977A1 (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
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CN100345831C (en) * | 2005-11-10 | 2007-10-31 | 吴永虎 | Prepn process of high purity 2, 6-dichloro quinoxaline |
CN101914069A (en) * | 2010-07-29 | 2010-12-15 | 安徽丰乐农化有限责任公司 | Novel chlorination technique of 6- chlorine-2-hydroxy quinoxaline |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4636562A (en) * | 1982-05-07 | 1987-01-13 | E. I. Du Pont De Nemours And Company | Process for preparing 6-halo-2-chloroquinoxaline |
IL86416A (en) * | 1987-06-19 | 1993-07-08 | Uniroyal Chem Co Inc | Process for the preparation of 2-quinoxalinol derivatives |
US4814444A (en) * | 1987-06-19 | 1989-03-21 | Uniroyal Chemical Company, Inc. | Process for the selective reduction of 2-hydroxyquinoxaline-4-oxides |
-
1989
- 1989-08-05 DE DE19893925969 patent/DE3925969A1/en not_active Withdrawn
-
1990
- 1990-07-16 CA CA 2064564 patent/CA2064564A1/en not_active Abandoned
- 1990-07-16 WO PCT/EP1990/001162 patent/WO1991001977A1/en not_active Application Discontinuation
- 1990-07-16 JP JP51067990A patent/JPH04507406A/en active Pending
- 1990-07-18 IN IN601/CAL/90A patent/IN169080B/en unknown
Also Published As
Publication number | Publication date |
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IN169080B (en) | 1991-08-31 |
DE3925969A1 (en) | 1991-02-07 |
WO1991001977A1 (en) | 1991-02-21 |
CA2064564A1 (en) | 1991-02-06 |
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