JP2701114B2 - Method for producing 3'-amino-2'-hydroxyacetophenone - Google Patents
Method for producing 3'-amino-2'-hydroxyacetophenoneInfo
- Publication number
- JP2701114B2 JP2701114B2 JP4242864A JP24286492A JP2701114B2 JP 2701114 B2 JP2701114 B2 JP 2701114B2 JP 4242864 A JP4242864 A JP 4242864A JP 24286492 A JP24286492 A JP 24286492A JP 2701114 B2 JP2701114 B2 JP 2701114B2
- Authority
- JP
- Japan
- Prior art keywords
- reaction
- formula
- compound
- producing
- reduction
- 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.)
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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
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Description
【0001】[0001]
【産業上の利用分野】本発明は、医薬品の中間体として
有用な式(I)The present invention relates to a compound of the formula (I) useful as an intermediate for pharmaceuticals
【0002】[0002]
【化3】 Embedded image
【0003】で示される3’−アミノ−2’−ヒドロキ
シアセトフェノン塩酸塩の製造方法に関する。The present invention relates to a method for producing 3'-amino-2'-hydroxyacetophenone hydrochloride represented by the formula:
【0004】[0004]
【従来の技術】式(I)で示される化合物は、ロイコト
リエンに起因するアレルギー性の各種疾患の治療剤とし
て有用な式(A)2. Description of the Related Art A compound represented by the formula (I) is useful as a therapeutic agent for various allergic diseases caused by leukotriene.
【0005】[0005]
【化4】 Embedded image
【0006】で示される8−[4−(4−フェニルブト
キシ)ベンゾイル]アミノ−2−(5−テトラゾリル)
−4−オキソ−4H−1−ベンゾピランを製造するため
の重要な中間体である。特開昭61−50977号明細
書には、式(B)8- [4- (4-phenylbutoxy) benzoyl] amino-2- (5-tetrazolyl)
It is an important intermediate for producing 4-oxo-4H-1-benzopyran. JP-A-61-50977 discloses a compound of the formula (B)
【0007】[0007]
【化5】 Embedded image
【0008】で示される化合物をキーの中間体とした式
(A)で示される医薬品の製造方法が記載されている。
また、特開平3−95144号明細書には、式(I)で
示される化合物をキーの中間体とした式(A)で示され
る医薬品の製造方法が記載されている。これまでに式
(I)で示される中間体の製造方法としては種々の方法
が提案されている。 例えば、特開平3−95144号
明細書では、下記反応工程式[A]で示される方法が提
案されている。また、特開平3−77852号明細書で
は、前記反応工程式[A]中の接触還元の工程を水/有
機溶媒の二相系で反応させる方法が開示されている。さ
らに、本発明者らは、特願平4−108449号(平成
4年4月2日出願)において、下記反応工程式[B]で
示されるような別途合成法も提案している。A method for producing a pharmaceutical product represented by the formula (A) using a compound represented by the following formula as a key intermediate is described.
Japanese Patent Application Laid-Open No. 3-95144 describes a method for producing a drug represented by the formula (A) using a compound represented by the formula (I) as a key intermediate. Until now, various methods have been proposed as methods for producing the intermediate represented by the formula (I). For example, JP-A-3-95144 proposes a method represented by the following reaction step formula [A]. Further, Japanese Patent Application Laid-Open No. 3-77852 discloses a method in which the step of catalytic reduction in the above reaction scheme [A] is performed in a two-phase system of water / organic solvent. Furthermore, the present inventors have proposed a separate synthesis method as shown in the following reaction scheme [B] in Japanese Patent Application No. 4-108449 (filed on April 2, 1992).
【0009】[0009]
【化6】 Embedded image
【0010】[0010]
【0011】[0011]
【化7】 Embedded image
【0012】[0012]
【0013】[0013]
【従来技術の問題点】反応工程式[A]で示される方法
は、式(I)で示される化合物の製造方法としては、
(1)選択的ニトロ化が可能である、(2)カラムクロ
マトグラフィーによる分離を必要としない、(3)原料
が他のルートのそれに比べ安価である、等の利点を有
し、工業的な製造方法としてはほぼ完成されたものであ
る。Problems of the Prior Art The method represented by the reaction formula [A] is a method for producing the compound represented by the formula (I),
(1) Selective nitration is possible, (2) Separation by column chromatography is not required, and (3) Raw materials are cheaper than those of other routes. The manufacturing method is almost completed.
【0014】しかしながら、4−クロロフェノール(す
なわち、式1において、Xaがクロロ基を表わす場合)
を出発原料として用いて反応工程式[A]に従って、式
(I)の化合物を製造すると最後の接触還元の工程の収
率が、p−ブロモフェノールを出発原料とした場合に比
べ劣っていることが判明した。However, 4-chlorophenol (ie, in formula 1, when Xa represents a chloro group)
When the compound of the formula (I) is produced according to the reaction process formula [A] using the compound of formula (I) as a starting material, the yield of the last step of catalytic reduction is inferior to the case of using p-bromophenol as a starting material. There was found.
【0015】[0015]
【問題点を解決するための手段】本発明者らは、反応工
程式[A]における5’−クロロ−3’−ニトロ−2’
−ヒドロキシアセトフェノン[式(II)で示される化
合物]の接触還元の反応条件について検討を重ねた。そ
の結果、通常の条件(中性または酸性条件下)で還元を
開始すると、ニトロ基の還元反応とクロロ基の脱離反応
とではニトロ基の還元反応の方が進みやすいこと、脱離
したクロルイオンと水素ガスが反応し塩酸が生成し、反
応液のpHが酸性側に傾くこと、酸性条件下ではクロロ
基の脱離反応が一層進みにくくなることが判明した。Means for Solving the Problems The present inventors have found that 5'-chloro-3'-nitro-2 'in the reaction scheme [A].
The reaction conditions for the catalytic reduction of -hydroxyacetophenone [compound represented by formula (II)] were repeated. As a result, when reduction is started under normal conditions (neutral or acidic conditions), the reduction reaction of the nitro group tends to proceed more easily between the reduction reaction of the nitro group and the elimination reaction of the chloro group. It was found that the ions react with the hydrogen gas to generate hydrochloric acid, the pH of the reaction solution was inclined to the acidic side, and the elimination reaction of the chloro group became more difficult to proceed under acidic conditions.
【0016】そこで、これらの知見をもとに、ニトロ基
の還元反応が完結した時点で、反応後のpHを中性付近
にもどし、引き続き接触還元反応を続行し、クロロ基の
脱離を完結させると、目的とする式(I)で示される化
合物が高収率で得られることを見い出し、本発明を完成
した。特開平3−95144号明細書では、該接触還元
が酸の存在下または不存在下に行なえること、また特開
平3−77852号明細書にも、酸の使用が反応を促進
させるとの記載はあるが、アルカリ条件下でクロロ基の
脱離反応が促進させる旨の記載はまったくない。さら
に、これらの事実は本発明者らにとってまったく予期さ
れないことであった。Therefore, based on these findings, when the reduction reaction of the nitro group is completed, the pH after the reaction is returned to near neutral, the catalytic reduction reaction is continued, and the elimination of the chloro group is completed. Then, the present inventors have found that the desired compound represented by the formula (I) can be obtained in high yield, and completed the present invention. JP-A-3-95144 describes that the catalytic reduction can be carried out in the presence or absence of an acid, and JP-A-3-77852 also describes that the use of an acid accelerates the reaction. However, there is no description that the elimination reaction of the chloro group is accelerated under alkaline conditions. Furthermore, these facts were completely unexpected for the inventors.
【0017】[0017]
【発明の構成】本発明は、式(II)The present invention relates to a compound of the formula (II)
【0018】[0018]
【化8】 Embedded image
【0019】で示される化合物のニトロ基の還元とクロ
ロ基の脱離を行なうための接触還元反応において、
(i)反応開始時は中性または酸性条件下で行ない、
(ii)ニトロ基の還元がほぼ完結した時点で、反応液
のpHを中性付近にもどし、引き続き接触還元反応を行
なうことを特徴とする、式(I)In the catalytic reduction reaction for reducing the nitro group and removing the chloro group of the compound represented by the following formula:
(I) at the beginning of the reaction, under neutral or acidic conditions,
(Ii) the formula (I) wherein the pH of the reaction solution is returned to around neutral when the reduction of the nitro group is almost completed, and the catalytic reduction reaction is carried out continuously.
【0020】[0020]
【化9】 Embedded image
【0021】で示される化合物の製造方法に関する。本
発明の接触還元を中性条件下で行なうには、不活性溶媒
[例えば、ハロゲン化炭化水素系(塩化メチレン、クロ
ロホルム、四塩化炭素、テトラクロロエタン、ヘキサク
ロロエタン等)、エーテル系(テトラヒドロフラン、テ
トラヒドロピラン、ジオキサン、ジエチルエーテル、ジ
メチルエーテル、ジイソプロピルエーテル、ジフェニル
エーテル、メチルエチルエーテル等)、アルコール系
(メタノール、エタノール、プロパノール、イソプロパ
ノール等)、炭化水素系(ペンタン、ヘキサン、オクタ
ン、シクロヘキサン等)、ケトン系(アセトン、メチル
エチルケトン、フェニルメチルケトン等)、N,N−ジ
メチルホルムアミド(以下、DMFと略記する)、酢
酸、酢酸エチル、またはそれらの2以上の混合溶媒]
中、水素化触媒(例えば、パラジウム炭素、パラジウム
黒、パラジウム、塩化パラジウム、水酸化パラジウム、
二酸化白金、ニッケル、ラネーニッケル等)の存在下、
常圧または加圧下の水素ガス中、0℃〜50℃、好まし
くは室温で行なわれる。The present invention relates to a method for producing the compound represented by In order to carry out the catalytic reduction of the present invention under neutral conditions, an inert solvent [for example, halogenated hydrocarbons (methylene chloride, chloroform, carbon tetrachloride, tetrachloroethane, hexachloroethane, etc.), ethers (tetrahydrofuran, tetrahydrofuran, etc.)] Pyran, dioxane, diethyl ether, dimethyl ether, diisopropyl ether, diphenyl ether, methyl ethyl ether, etc.), alcohols (methanol, ethanol, propanol, isopropanol, etc.), hydrocarbons (pentane, hexane, octane, cyclohexane, etc.), ketones ( Acetone, methyl ethyl ketone, phenyl methyl ketone, etc.), N, N-dimethylformamide (hereinafter abbreviated as DMF), acetic acid, ethyl acetate, or a mixed solvent of two or more thereof.
Medium, hydrogenation catalyst (for example, palladium carbon, palladium black, palladium, palladium chloride, palladium hydroxide,
In the presence of platinum dioxide, nickel, Raney nickel, etc.)
The reaction is carried out at 0 ° C. to 50 ° C., preferably at room temperature, in hydrogen gas at normal pressure or under pressure.
【0022】酸性条件下で行なうには、無機酸(例え
ば、塩酸、硫酸等)または有機酸(例えば、酢酸、p−
トルエンスルホン酸、ギ酸等)の存在下で上記還元反応
を進行すればよい。酸性条件下で行なうとニトロ基の還
元反応が促進される。ニトロ基の還元反応の完結は薄層
クロマトグラフィー等で確認することができる。ニトロ
基の還元反応がほぼ完結した時点で反応液のpHを中性
付近(pH6〜8)にもどす。反応液の中和は、アルカ
リ金属またはアルカリ土類金属の水酸化物、炭酸塩、炭
酸水素塩または酢酸塩(例えば、水酸化ナトリウム、炭
酸ナトリウム、炭酸水素ナトリウム、酢酸ナトリウム
等)または有機アミン(トリエチルアミン等)を加える
ことによって行なわれる。In order to carry out the reaction under acidic conditions, an inorganic acid (eg, hydrochloric acid, sulfuric acid, etc.) or an organic acid (eg, acetic acid, p-
The above reduction reaction may proceed in the presence of toluenesulfonic acid, formic acid, etc.). When performed under acidic conditions, the reduction reaction of the nitro group is promoted. Completion of the reduction reaction of the nitro group can be confirmed by thin layer chromatography or the like. When the reduction reaction of the nitro group is almost completed, the pH of the reaction solution is returned to around neutral (pH 6 to 8). Neutralization of the reaction solution is performed by using a hydroxide, carbonate, hydrogencarbonate or acetate of an alkali metal or alkaline earth metal (for example, sodium hydroxide, sodium carbonate, sodium hydrogencarbonate, sodium acetate, etc.) or an organic amine ( Triethylamine, etc.).
【0023】式(II)で示される化合物は、特開平3
−95144号明細書に記載の方法により製造すること
ができる。The compound represented by the formula (II) is disclosed in
It can be produced by the method described in -95144.
【0024】[0024]
【効果】本発明方法は、途中で生成物を単離すること
も、溶媒や触媒を替える必要もなく(ワンバッチで行な
える)かつ収率よく目的化合物を得ることのできる工業
的にすぐれた方法である。The method of the present invention is an industrially superior method that can obtain the target compound in good yield without isolating the product on the way and without changing the solvent or catalyst (can be performed in one batch). It is.
【0025】[0025]
【実施例】以下、参考例および実施例によって本発明を
詳述するが、本発明はこれらに限定されるものではな
い。 参考例1 4−クロロフェニルアセテートEXAMPLES The present invention will now be described in detail with reference to Examples and Examples, but the present invention is not limited thereto. Reference Example 1 4-chlorophenyl acetate
【0026】[0026]
【化10】 Embedded image
【0027】無水酢酸(11.3ml)に濃硫酸(0.05m
l)を加えて25℃でかくはんした。ここへp−クロロ
フェノール(12.856g)をゆっくり加えていった。少し
発熱するが、そのまま3時間かくはんした。その後、n
−ヘキサン(50ml)を加えて希釈し、水(50m
l)で2回洗浄した。無水硫酸マグネシウムで乾燥した
後濃縮し、次の物性値を有する標題化合物(16.96g)
を粗生成物として得た。 TLC:Rf0.46(ベンゼン)。 参考例2 2’−ヒドロキシ−5’クロロアセトフェノンConcentrated sulfuric acid (0.05m) in acetic anhydride (11.3ml)
1) and stirred at 25 ° C. To this was slowly added p-chlorophenol (12.856 g). It generated a little heat, but was stirred for 3 hours. Then n
-Hexane (50 ml) was added for dilution, and water (50 m
Washed twice in l). After drying over anhydrous magnesium sulfate and concentrating, the title compound having the following physical data (16.96 g)
Was obtained as a crude product. TLC: Rf 0.46 (benzene). Reference Example 2 2'-hydroxy-5 'chloroacetophenone
【0028】[0028]
【化11】 Embedded image
【0029】塩化カルシウム管をつけた反応容器にo−
ジクロロベンゼン(40ml)と塩化アルミニウム(2
0g)を加えてかくはんし、130℃まで昇温した。こ
こへアセテート体(参考例1で製造した、16.96g)を
ゆっくり滴下した。滴下後さらに130℃で1時間反応
させた後、放冷した。次に反応溶液を濃塩酸(20m
l)と氷(80ml)の中へかくはんしながら移した
後、塩化メチレン(40ml)で抽出した。さらに水層
に2N塩酸(40ml)と塩化メチレン(40ml)を
加えて抽出した。次に有機層を合わせて2N塩酸(40
ml)と水(40ml)で洗い、無水硫酸マグネシウム
で乾燥した後濃縮した。得られた粗生成物にメタノール
(20ml)を加えてかくはんし、種晶を加えて冷却す
ると結晶が析出した。一次晶として標題化合物(5.76
g)を得た。さらに母液にエタノール(10ml)を加
えてかくはんし、種晶を加えて冷却すると、二次晶とし
て標題化合物(3.65g)を得た。標題化合物は次の物性
値を有していた。 TLC:Rf0.65(ベンゼン) NMR(CDCl3)200MHz δ12.14(s,H),7.69(d,H,J=2.4Hz),7.42
(dd,H,J=9,2.4Hz)6.94(d,H,J=9H
z),2.63(s,3H) 参考例3 5’−クロロ−3’−ニトロ−2’−ヒトロキシアセト
フェノンIn a reaction vessel equipped with a calcium chloride tube, o-
Dichlorobenzene (40 ml) and aluminum chloride (2
0 g), and the mixture was stirred and heated to 130 ° C. The acetate body (16.96 g produced in Reference Example 1) was slowly added dropwise thereto. After the addition, the mixture was further reacted at 130 ° C. for 1 hour, and then allowed to cool. Next, the reaction solution was concentrated hydrochloric acid (20 m
1) and transferred to ice (80 ml) with stirring, and extracted with methylene chloride (40 ml). The aqueous layer was further extracted by adding 2N hydrochloric acid (40 ml) and methylene chloride (40 ml). Next, the organic layers were combined and 2N hydrochloric acid (40
ml) and water (40 ml), dried over anhydrous magnesium sulfate and concentrated. Methanol (20 ml) was added to the obtained crude product, the mixture was stirred, seed crystals were added, and the mixture was cooled to precipitate crystals. The title compound (5.76
g) was obtained. Further, ethanol (10 ml) was added to the mother liquor, stirred, seed crystals were added, and the mixture was cooled to obtain the title compound (3.65 g) as secondary crystals. The title compound had the following physical data. TLC: Rf 0.65 (benzene) NMR (CDCl 3) 200 MHz δ 12.14 (s, H), 7.69 (d, H, J = 2.4 Hz), 7.42
(Dd, H, J = 9, 2.4 Hz) 6.94 (d, H, J = 9H
z), 2.63 (s, 3H) Reference Example 3 5'-chloro-3'-nitro-2'-hydroxylacetophenone
【0030】[0030]
【化12】 Embedded image
【0031】塩化カルシウム管を付けた反応容器にアセ
トフェノン体(参考例2で製造した、1.706g)のジク
ロロエタン溶液(5ml)を入れ、ここにメタンスルホ
ン酸(1ml)を加えてかくはんし、0℃に冷却した。
次に濃硝酸(1.5ml)をゆっくり加えていった。30
分間かくはんした後、n−ヘキサン(10ml)を加え
てかくはんし、析出した結晶を濾取し水洗、乾燥して次
の物性値を有する標題化合物(1.70g)を得た。 TLC:Rf0.30(ベンゼン) NMR(CDCl3)200MHz δ12.84(s,H),8.19(d,H,J=2.6Hz),8.01
(d,H,J=2.6Hz)2.73(s,3H) 実施例1 3’−アミノ−2’−ヒドロキシアセトフェノンハイド
ロクロライドA reaction vessel equipped with a calcium chloride tube was charged with a solution (5 ml) of an acetophenone compound (1.706 g prepared in Reference Example 2) in dichloroethane, and methanesulfonic acid (1 ml) was added thereto, and the mixture was stirred at 0 ° C. And cooled.
Next, concentrated nitric acid (1.5 ml) was slowly added. 30
After stirring for minutes, n-hexane (10 ml) was added and the mixture was stirred, and the precipitated crystals were collected by filtration, washed with water and dried to give the title compound (1.70 g) having the following physical data. TLC: Rf 0.30 (benzene) NMR (CDCl 3) 200 MHz δ 12.84 (s, H), 8.19 (d, H, J = 2.6 Hz), 8.01
(D, H, J = 2.6 Hz) 2.73 (s, 3H) Example 1 3'-amino-2'-hydroxyacetophenone hydrochloride
【0032】[0032]
【化13】 Embedded image
【0033】クロロニトロフェノール体(参考例3で製
造した、216mg)のイソプロパノール溶液(3.5m
l)に5%パラジウム炭素(10mg)を加えて25℃
で水素雰囲気下3時間かくはんした。TLCで原料のス
ポットの消失を確認した後、酢酸ナトリウム・3水和物
(204mg)を加え、さらに水素雰囲気下4時間かく
はんした。反応終了後、反応溶液を酢酸エチルで希釈し
た後濾別し、濾液に濃塩酸を加えると結晶が析出した。
結晶を濾取して酢酸エチルで洗い、次の物性値を有する
標題化合物(170mg)を得た。 TLC:Rf0.55(n−ヘキサン:酢酸エチル=1:
1) NMR(CD3OD)200MHz δ8.05(dd,H,J=8,1.5Hz),7.63(dd,H,J
=8,1.5Hz),7.11(dd,H,J=8,8Hz),2.7
1(s,3H)A solution of a chloronitrophenol compound (216 mg produced in Reference Example 3) in isopropanol (3.5 m
5) palladium on carbon (10 mg)
For 3 hours under a hydrogen atmosphere. After confirming disappearance of the spot of the raw material by TLC, sodium acetate trihydrate (204 mg) was added, and the mixture was further stirred under a hydrogen atmosphere for 4 hours. After completion of the reaction, the reaction solution was diluted with ethyl acetate and filtered off, and concentrated hydrochloric acid was added to the filtrate to precipitate crystals.
The crystals were collected by filtration and washed with ethyl acetate to give the title compound (170 mg) having the following physical data. TLC: Rf0.55 (n-hexane: ethyl acetate = 1:
1) NMR (CD3OD) 200 MHz δ 8.05 (dd, H, J = 8, 1.5 Hz), 7.63 (dd, H, J
= 8,1.5 Hz), 7.11 (dd, H, J = 8.8 Hz), 2.7
1 (s, 3H)
Claims (1)
行なうための接触還元反応において、(i)反応開始時
は中性または酸性条件下で行ない、(ii)ニトロ基の
還元がほぼ完結した時点で、反応液のpHを中性付近に
もどし、引続き接触還元反応を行なうことを特徴とす
る、式(I) 【化2】 で示される化合物の製造方法。1. A compound of the formula (II) In the catalytic reduction reaction for the reduction of the nitro group and the elimination of the chloro group of the compound represented by the formula (i), the reaction is carried out under neutral or acidic conditions at the start of the reaction, and (ii) the reduction of the nitro group is almost completed. At the time of the reaction, the pH of the reaction solution is returned to around neutral, and the catalytic reduction reaction is carried out continuously. A method for producing a compound represented by the formula:
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JP4242864A JP2701114B2 (en) | 1992-09-11 | 1992-09-11 | Method for producing 3'-amino-2'-hydroxyacetophenone |
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JP4242864A JP2701114B2 (en) | 1992-09-11 | 1992-09-11 | Method for producing 3'-amino-2'-hydroxyacetophenone |
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JPH0692916A JPH0692916A (en) | 1994-04-05 |
JP2701114B2 true JP2701114B2 (en) | 1998-01-21 |
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JP4242864A Expired - Fee Related JP2701114B2 (en) | 1992-09-11 | 1992-09-11 | Method for producing 3'-amino-2'-hydroxyacetophenone |
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JP5938358B2 (en) * | 2013-02-28 | 2016-06-22 | 株式会社日立製作所 | Optical module lifetime prediction system, optical module lifetime prediction apparatus, optical module lifetime prediction method, and optical module lifetime prediction program |
CN104402728A (en) * | 2014-11-21 | 2015-03-11 | 山东金城医药化工股份有限公司 | Preparation method for 5-chlorine-2-hydroxyl-3-nitroacetophenone |
CN108911988B (en) * | 2018-06-14 | 2020-11-06 | 昆山力田医化科技有限公司 | Green synthesis method of 2-hydroxy-3-nitroacetophenone |
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1992
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