JPH062719B2 - Process for producing halo-substituted aminophenols - Google Patents
Process for producing halo-substituted aminophenolsInfo
- Publication number
- JPH062719B2 JPH062719B2 JP60291951A JP29195185A JPH062719B2 JP H062719 B2 JPH062719 B2 JP H062719B2 JP 60291951 A JP60291951 A JP 60291951A JP 29195185 A JP29195185 A JP 29195185A JP H062719 B2 JPH062719 B2 JP H062719B2
- Authority
- JP
- Japan
- Prior art keywords
- halo
- substituted
- reaction
- nitrophenol
- chloro
- 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.)
- Expired - Lifetime
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Landscapes
- Catalysts (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Description
【発明の詳細な説明】 産業上の利用分野 本発明はハロ置換アミノフエノール類の製造方法に関す
る。更に詳しくは水添法によるハロ置換アミノフエノー
ル類の製造方法に関する。TECHNICAL FIELD The present invention relates to a method for producing halo-substituted aminophenols. More specifically, it relates to a method for producing halo-substituted aminophenols by a hydrogenation method.
従来の技術 ハロ置換アミノフエノール類は医薬、農薬用の重要な中
間体である。Prior Art Halo-substituted aminophenols are important intermediates for pharmaceuticals and agricultural chemicals.
ハロ置換アミノフエノール類の製法としては ポリハロ置換フエノール類の選択的アンモノリシスあ
るいはハロ置換ニトロフエノール類の接触還元による
方法等が知られている。Known methods for producing halo-substituted aminophenols include selective ammonolysis of polyhalo-substituted phenols or catalytic reduction of halo-substituted nitrophenols.
例えばについては、特開昭５７−７４５１の方法があ
るが、その収率は約８０％と低く満足のいくものではな
い。For example, there is a method disclosed in JP-A-57-7451, but the yield is low at about 80%, which is not satisfactory.
またについては、例えば特開昭５９−２１６８５５が
あるが、この方法では、脱ハロゲン防止や核水添防止の
ため高価な白金触媒を用いているがコストアツプをさけ
る為に厳密な触媒回収を行う必要があり、またその生産
性（仕込み効率）も低く総じて工業的に満足のいくもの
ではない。Regarding this, for example, there is JP-A-59-216855, but in this method, an expensive platinum catalyst is used for preventing dehalogenation and nuclear hydrogenation, but strict catalyst recovery is necessary to avoid cost up. Moreover, its productivity (preparation efficiency) is low, and it is not industrially satisfactory in general.
発明が解決しようとする問題点 工業的に容易に入手しうる触媒を用いて 脱ハロゲン反応、核水添反応等による副生成物が少
ない。Problems to be Solved by the Invention There are few by-products due to dehalogenation reaction, nuclear hydrogenation reaction, etc. using a catalyst that is easily industrially available.
仕込み効率が高い。 High charging efficiency.
等を満足するハロゲン置換アミノフエノール類の製造法
の開発が望まれている。It is desired to develop a method for producing a halogen-substituted aminophenol that satisfies the above requirements.
問題点を解決するための手段 本発明者らは前記したような問題点を解決する為に鋭意
研究を重ねた結果本発明に至ったものである。即ち本発
明は ラネーニツケル触媒、シアノ化合物又はチアゾール類及
びアルカリ剤を含有する水性媒体に水素加圧下ハロ置換
ニトロフエノール類のアルコール溶液を供給し水素還元
することを特徴とするハロ置換アミノフエノール類の製
造方法を提供する。Means for Solving the Problems The present inventors have achieved the present invention as a result of intensive studies to solve the above-mentioned problems. That is, the present invention is a method for producing a halo-substituted aminophenol which is characterized in that an alcoholic solution of a halo-substituted nitrophenol is supplied under hydrogen pressure to an aqueous medium containing a Raney-Nitzkel catalyst, a cyano compound or a thiazole and an alkaline agent to carry out hydrogen reduction. Provide a way.
工業的に安価に入手出来るラネーニツケルを用いる接触
還元水添では触媒の性質上中性あるいは弱アルカリ性で
反応するが一般的であるが、ハロ置換ニトロフエノール
類の水添においてもこのもの自体が酸性を示す物質であ
るためそのアルカリ金属塩としてから反応させるのが一
般的である。しかしながらこのハロ置換ニトロフエノー
ル類のアルカリ金属塩は、溶媒、特に水に対する溶解度
が極めて低いため水溶液での取り扱いは工業上ほとんど
意味がなく、スラリーでの取り扱いとなるがこのスラリ
ーにしてもハロ置換ニトロフエノールの種類にもよるが
せいぜい１５％〜２０％程度の濃度が上限でそれ以上の
濃度では撹拌が充分にできなくなり、仕込みにおける効
果及び反応上の問題が生じる。Catalytic reduction hydrogenation using Raney-Nitzkel, which is industrially available at low cost, generally reacts with neutrality or weak alkalinity due to the nature of the catalyst, but even in the hydrogenation of halo-substituted nitrophenols, this is itself acidic. Since it is a substance shown, it is general to react it as its alkali metal salt. However, since the alkali metal salt of this halo-substituted nitrophenol has extremely low solubility in a solvent, especially water, its handling in an aqueous solution is industrially meaningless, and it is handled as a slurry. Although depending on the type of phenol, the concentration is at most 15% to 20% at the upper limit, and if the concentration is higher than that, stirring cannot be sufficiently performed, and problems in charging and reaction occur.
本発明を詳しく説明する。The present invention will be described in detail.
本発明でいうハロ置換ニトロフエノール類の具体例とし
ては、２−クロル−４−ニトロフエノール、４−クロル
−２−ニトロフエノール、２−ブロム−４−ニトロフエ
ノール、４−ブロム−２−ニトロフエノール、2,6−ジ
クロル−４−ニトロフエノール、2,6−ジブロム−４−
ニトロフエノール、４−クロル−６−ニトロメタクレゾ
ール、２−クロル−４−ニトロ−６−メトキシメチルフ
エノール、２−クロル−４−ニトロ−６−エトキシフエ
ノール、２−クロル−４−ニトロ−６−メチルフエノー
ル等があげられるが、これらに限定されるものではな
い。Specific examples of the halo-substituted nitrophenols referred to in the present invention include 2-chloro-4-nitrophenol, 4-chloro-2-nitrophenol, 2-bromo-4-nitrophenol, 4-bromo-2-nitrophenol. , 2,6-dichloro-4-nitrophenol, 2,6-dibromo-4-
Nitrophenol, 4-chloro-6-nitrometacresol, 2-chloro-4-nitro-6-methoxymethylphenol, 2-chloro-4-nitro-6-ethoxyphenol, 2-chloro-4-nitro-6- Examples thereof include, but are not limited to, methylphenol and the like.
ハロ置換ニトロフエノール類のアルコール溶液を調製す
る為に使用されるアルコールの具体例としては、メタノ
ール、エタノール、プロピルアルコール、イソプロピル
アルコール、ブタノール、メチルセロソルブ等が挙げら
れるが特に有利なものはメタノールである。Specific examples of the alcohol used for preparing the alcohol solution of the halo-substituted nitrophenol include methanol, ethanol, propyl alcohol, isopropyl alcohol, butanol, and methyl cellosolve, but methanol is particularly advantageous. .
使用するアルコールの量は該アルコールの沸点以下常温
において、原料のハロ置換ニトロフエノール類を溶解で
きる量かそれよりわずかに多目に用いるのが望ましく通
常ハロ置換ニトロフエノール類１００部に対して５０〜
２００部である（ハロ置換ニトロフエノール類は一般に
融点が高いが、熱安定性が良くないため、溶融状態での
取り扱いはさけた方が望ましい）。The amount of the alcohol to be used is not more than the boiling point of the alcohol, and it is desirable to use the starting halo-substituted nitrophenols at a room temperature or a slightly larger amount than that at a normal temperature.
200 parts (Halo-substituted nitrophenols generally have a high melting point, but their thermal stability is poor, so it is desirable to avoid handling in the molten state).
反応に用いるラネーニツケル触媒は、市販の展開したペ
ーストをそのまま用いてもよいし活性を落す為に常法に
より酸性亜硫酸ナトリウム、酸性亜硫酸アンモニウム等
で処理してもよく、その使用量はハロ置換ニトロフエノ
ール類１００部に対し0.1〜２０部好ましくは２〜５部
である。また、アルカリ剤は、反応で生成したハロ置換
アミノフエノール類がアルカリ金属塩となるに必要な量
以上であれば良く、通常はハロ置換ニトロフエノール類
１モルに対し、0.9〜1.1モル程度用いられる。アルカリ
剤としては水素化ナトリウム、酸化マグネシウム、水酸
化マグネシウム、水酸化カリ炭酸ナトリウム、水酸化カ
ルシウム等が用いられるが特に好ましいものは水酸化ナ
トリウムである。アルカリ剤は反応器内に一度に加えて
もよくまたニトロ化合物の供給と併行して連続的に加え
てもよい。アルカリ剤は固体状で加えてもよいが通常は
水溶液として加えられる。The Raney-Nitzkel catalyst used in the reaction may be a commercially available paste as it is, or may be treated with sodium acid sulfite, ammonium sulfite, etc. by a conventional method in order to reduce the activity, and the amount used is a halo-substituted nitrophenol. It is 0.1 to 20 parts, preferably 2 to 5 parts per 100 parts. The alkali agent may be used in an amount of at least the amount necessary for the halo-substituted aminophenols formed by the reaction to form an alkali metal salt, and is usually used in an amount of about 0.9 to 1.1 mol per 1 mol of the halo-substituted nitrophenols. . As the alkaline agent, sodium hydride, magnesium oxide, magnesium hydroxide, potassium hydroxide carbonate, calcium hydroxide and the like can be used, but sodium hydroxide is particularly preferable. The alkaline agent may be added at once to the reactor or may be added continuously in parallel with the supply of the nitro compound. The alkaline agent may be added in a solid form, but is usually added as an aqueous solution.
またシアノ化合物又はチアゾール類の具体例としては、
ジアミノマレオニトリル、コハク酸ニトリル、ジメチル
シアナミド、β−アミノプロピオニトリル、α−シアノ
アセトアミド、メチレンアミノアセトニトリル、３−シ
アノピリジン、イミノジアセトニトリル、シアナミド、
ジシアンジアミド、２−アミノチアゾール、ベンゾチア
ゾール等が挙げられるが特に好ましいものはジアナミ
ド、ジシアンジアミド、２−アミノチアゾール、ベンゾ
チアゾールであり、それらは混合して用いてもよく又そ
の使用量はハロ置換ニトロフエノール類１００部に対し
0.5〜１０部用いられる。Further, specific examples of the cyano compound or thiazoles include:
Diaminomaleonitrile, succinonitrile, dimethylcyanamide, β-aminopropionitrile, α-cyanoacetamide, methyleneaminoacetonitrile, 3-cyanopyridine, iminodiacetonitrile, cyanamide,
Although dicyandiamide, 2-aminothiazole, benzothiazole and the like are mentioned, particularly preferable ones are dianamide, dicyandiamide, 2-aminothiazole and benzothiazole, which may be used as a mixture or the amount thereof is a halo-substituted nitrophenol. For 100 parts
Used from 0.5 to 10 parts.
ラネーニツケル触媒、シアノ化合物又はチアゾール類及
びアルカリ剤を含有する水性媒体を調製するには通常水
が媒体として用いられるが例えばメタノール、エタノー
ルプロパノールのような水溶性のアルコールを含有した
水を用いてもよい。反応における、水素圧力は任意であ
るが、通常0.5〜２０kg/cm2好ましくは２〜１０kg/cm2
であり、反応温度は、室温以上〜１５０℃であり、好ま
しくは６０〜９０℃である。反応時間はハロ置換ニトロ
フエノール類のアルコール溶液の供給時間によつて決定
されるが、通常２〜１０時間である。Water is usually used as a medium for preparing an aqueous medium containing a Raney-Nitzkel catalyst, a cyano compound or a thiazole and an alkaline agent, but water containing a water-soluble alcohol such as methanol or ethanol propanol may be used. . The hydrogen pressure in the reaction is arbitrary, but is usually 0.5 to 20 kg / cm 2, preferably 2 to 10 kg / cm 2.
The reaction temperature is room temperature or higher to 150 ° C, preferably 60 to 90 ° C. The reaction time is determined depending on the feeding time of the alcohol solution of the halo-substituted nitrophenol, but it is usually 2 to 10 hours.
本発明の方法によつて、得られた反応液は、触媒を分離
した後アルコールを蒸留により除いた後酸で中和・別
することにより容易に目的のハロ置換アミノフエノール
類を得ることができる。According to the method of the present invention, the obtained reaction liquid can easily obtain the desired halo-substituted aminophenols by separating the catalyst, removing the alcohol by distillation, and then neutralizing and separating with an acid. .
本発明の方法は脱ハロゲン反応、核水添反応等による副
生物の生成が少ない、又仕込み効率がたかくかつ安価な
触媒として容易に入手しうるラネーニツケル触媒を使用
する等の理由からハロ置換アミノフエノール類の製造法
として極めて有利な製造方法である。In the method of the present invention, a halo-substituted aminophenol is used because it produces less by-products due to a dehalogenation reaction, a nuclear hydrogenation reaction, etc., and uses a Raney-Nitzkel catalyst that is easily available as an inexpensive catalyst with a high charging efficiency. It is a very advantageous manufacturing method as a manufacturing method of a class.
実施例 本発明の方法を実施例によつて更に詳細に説明する。EXAMPLES The method of the present invention will be described in more detail by way of examples.
実施例１ オートクレーブにラネーニツケル１０ｇ、ジシアンジア
ミド3.0ｇ、２０％苛性ソーダ水溶液１００ｇを加え、
水素圧力８kg/cm2に調整して撹拌しながら８５℃に昇温
した。Example 1 To an autoclave was added 10 g of Raney-Neckel, 3.0 g of dicyandiamide, 100 g of 20% aqueous sodium hydroxide solution,
The hydrogen pressure was adjusted to 8 kg / cm 2 and the temperature was raised to 85 ° C. with stirring.
ついで、2,6−ジクロル−４−ニトロフエノール１０４
ｇをメタノール６０ｇ（７５ml）に溶解した溶液を加圧
注入ポンプを用いて３時間を要してオートクレーブ中に
注入し反応を行つた。水素吸収が終了してからさらに２
０分間、同温度、同圧力で熟成を行つた後、室温まで冷
却した。ガスクロマトグラフイーによる反応液の組成
は、2,6−ジクロル−４−アミノフエノール（目的物）9
9.8鵜、２−クロル−４−アミノフエノール0.02％2,6−
ジクロル−４−アミノシクロヘキサノール0.18であつ
た。Then, 2,6-dichloro-4-nitrophenol 104
A solution prepared by dissolving 60 g of methanol in 60 g (75 ml) was injected into the autoclave for 3 hours using a pressure injection pump to carry out the reaction. 2 more after hydrogen absorption is completed
After aging for 0 minutes at the same temperature and the same pressure, the mixture was cooled to room temperature. The composition of the reaction solution by gas chromatography was 2,6-dichloro-4-aminophenol (target compound) 9
9.8 Cormorant, 2-chloro-4-aminophenol 0.02% 2,6-
It was 0.18 dichloro-4-aminocyclohexanol.
触媒を別した後、３５％塩酸52.9ｇで中和し、析出し
た結晶を取、水洗後乾燥して99.9％の純度の2,6−ジ
クロル−４−アミノフエノール８６ｇを得た。これは対
理論の96.6％の収率であつた。After separating the catalyst, it was neutralized with 52.9 g of 35% hydrochloric acid, and the precipitated crystals were washed with water and dried to obtain 86 g of 2,6-dichloro-4-aminophenol having a purity of 99.9%. This was a yield of 96.6% of theory.
実施例２ オートクレーブに、実施例１においてジシアンジアミド
3.0ｇの代りに、２−アミノチアゾール1.0ｇを加える他
は実施例１と同様にして反応を行つた。反応終了後にお
けるガスクロマトグラフイーによる反応液の組成は、2,
6−ジクロル−４−アミノフエノール（目的物）99.7
％、２−クロル−４−アミノフエノール0.2％、2,6−ジ
クロル−４−アミノシクロヘキサノール0.1％であつ
た。Example 2 In an autoclave, the dicyandiamide in Example 1
The reaction was carried out in the same manner as in Example 1 except that 1.0 g of 2-aminothiazole was added instead of 3.0 g. After completion of the reaction, the composition of the reaction solution by gas chromatography is 2,
6-dichloro-4-aminophenol (target product) 99.7
%, 2-chloro-4-aminophenol 0.2%, and 2,6-dichloro-4-aminocyclohexanol 0.1%.
実施例３ オートクレーブに、ラネーニツケル8.0ｇジシアンジア
ミド4.0、３５％苛性ソーダ水溶液57.2ｇを加え、水素
圧力１０kg/cm2に調整し８０℃に昇温した。次に２−ク
ロル−４−ニトロフエノール86.75ｇをメタノール６０
ｇに溶かした溶液を、実施例１と同様にして2.5時間を
要して同オートクレーブに注入した。水素吸収停止後２
０分間同温度、同圧力で熟成を行い反応を終了させた。
ガスクロマトグラフイーによる反応液の組成は、２−ク
ロル−４−アミノフエノール（目的物）99.7％、４−ア
ミノフエノール0.1％、４−アミノシクロヘキサノール
0.1％、２−クロル−４−アミノシクロヘキサノール0.1
％であつた。反応液から触媒を別した後、実施例１と
同様にして純度99.9％の２−クロル−４−アミノフエノ
ール６８ｇを得た。これは対理論の９５％の収率であつ
た。Example 3 To an autoclave, 8.0 g of Raney-Nickel dicyandiamide 4.0 and 57.2 g of 35% aqueous sodium hydroxide solution were added, the hydrogen pressure was adjusted to 10 kg / cm 2 , and the temperature was raised to 80 ° C. Next, 86.75 g of 2-chloro-4-nitrophenol was added to 60 parts of methanol.
The solution dissolved in g was injected into the same autoclave as in Example 1 for 2.5 hours. After stopping hydrogen absorption 2
The reaction was terminated by aging for 0 minutes at the same temperature and the same pressure.
The composition of the reaction solution by gas chromatography was 2-chloro-4-aminophenol (target product) 99.7%, 4-aminophenol 0.1%, 4-aminocyclohexanol.
0.1%, 2-chloro-4-aminocyclohexanol 0.1
It was in%. After removing the catalyst from the reaction solution, 68 g of 2-chloro-4-aminophenol having a purity of 99.9% was obtained in the same manner as in Example 1. This was a yield of 95% of the theory.
実施例４ 実施例１において、2,6−ジクロル−４−ニトロフエノ
ール１０４ｇの代りに２−クロル−４−ニトロ−６メチ
ルフエノール94.25ｇを用いた他は実施例１と同様にし
て反応を行つた。反応終了時のガスクロマトグラフイー
による反応液の組成は、２−クロル−４−アミノ−６−
メチルフエノール（目的物）99.9、核水添物0.1％であ
つた。反応液を実施例１と同様に処理して、純度99.9％
の２−クロル−４−アミノ−６−メチルフエノールを対
理論の９７％で得た。Example 4 The reaction was carried out in the same manner as in Example 1 except that 94.25 g of 2-chloro-4-nitro-6-methylphenol was used in place of 104 g of 2,6-dichloro-4-nitrophenol in Example 1. Ivy. At the end of the reaction, the composition of the reaction solution by gas chromatography was 2-chloro-4-amino-6-
Methylphenol (target product) was 99.9 and the nuclear hydrogenated product was 0.1%. The reaction mixture was treated as in Example 1 to give a purity of 99.9%.
2-chloro-4-amino-6-methylphenol was obtained in 97% of theory.
発明の効果 安価で入手の容易なラネーニツケル触媒を用い脱ハロゲ
ン、核水添等による副生物が少なく、高い生産性で、ハ
ロ置換アミノフエノール類を高収率で製造することが出
来るようになつた。EFFECTS OF THE INVENTION It has become possible to produce halo-substituted aminophenols in a high yield with high productivity by using a cheap and easily available Raney-Nitzkel catalyst with little by-products such as dehalogenation and nuclear hydrogenation. .
Claims (1)
アゾール類及びアルカリ剤を含有する水性媒体に水素加
圧下ハロ置換ニトロフエノール類のアルコール溶液を供
給し水素還元することを特徴とするハロ置換アミノフエ
ノール類の製造方法1. A halo-substituted aminophenol which is characterized in that an alcoholic solution of a halo-substituted nitrophenol is supplied under hydrogen pressure to an aqueous medium containing a Raney-Nitzkel catalyst, a cyano compound or a thiazole and an alkaline agent to carry out hydrogen reduction. Production method
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60291951A JPH062719B2 (en) | 1985-12-26 | 1985-12-26 | Process for producing halo-substituted aminophenols |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60291951A JPH062719B2 (en) | 1985-12-26 | 1985-12-26 | Process for producing halo-substituted aminophenols |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62153262A JPS62153262A (en) | 1987-07-08 |
| JPH062719B2 true JPH062719B2 (en) | 1994-01-12 |
Family
ID=17775570
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60291951A Expired - Lifetime JPH062719B2 (en) | 1985-12-26 | 1985-12-26 | Process for producing halo-substituted aminophenols |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH062719B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2632951B1 (en) * | 1988-06-15 | 1990-09-21 | Rhone Poulenc Chimie | PROCESS FOR THE PREPARATION OF DICHLORO-2,6 AMINO-4 PHENOL |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL7311193A (en) * | 1972-08-19 | 1974-02-21 |
-
1985
- 1985-12-26 JP JP60291951A patent/JPH062719B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62153262A (en) | 1987-07-08 |
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