JPH07109244A - Production of 5-bromo-2-pentanone - Google Patents

Production of 5-bromo-2-pentanone

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Publication number
JPH07109244A
JPH07109244A JP25316293A JP25316293A JPH07109244A JP H07109244 A JPH07109244 A JP H07109244A JP 25316293 A JP25316293 A JP 25316293A JP 25316293 A JP25316293 A JP 25316293A JP H07109244 A JPH07109244 A JP H07109244A
Authority
JP
Japan
Prior art keywords
hydrobromic acid
pentanone
butyrolactone
bromo
acetyl
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
Application number
JP25316293A
Other languages
Japanese (ja)
Inventor
Hiroshi Yoshida
浩 吉田
Kiyoshi Omori
潔 大森
Hiroyuki Miyata
博之 宮田
Junichi Hashimoto
淳一 橋本
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ube Corp
Original Assignee
Ube Industries Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Ube Industries Ltd filed Critical Ube Industries Ltd
Priority to JP25316293A priority Critical patent/JPH07109244A/en
Publication of JPH07109244A publication Critical patent/JPH07109244A/en
Pending legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/61—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups
    • C07C45/67—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton
    • C07C45/673—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton by change of size of the carbon skeleton

Abstract

PURPOSE:To produce 5-bromo-2-pentanone useful as a synthetic intermediate for agrochemicals and)harmaceuticals in a high yield with decreased consumption of hydrobromic acid by reacting alpha-acetyl-gamma-butyrolactone with hydrobromic acid in a scarcely water-soluble solvent in the presence of sulfuric acid. CONSTITUTION:5-Bromo-2-pentanone is produced by reacting alpha-acetyl-gamma- butyrolactone with hydrobromic acid in a scarcely water-soluble solvent (e.g. benzene, toluene, xylene, dichloroethane and cyclohexane) in the presence of sulfuric acid. Hydrobromic acid having a concentration of about 47wt.% and often used in industrial use is preferably used in the above reaction. The amount of the hydrobromic acid is preferably 0.8-1.3mol based on 1mol of the alpha-acetyl-gamma- butyrolactone and that of the solvent is preferably 4-15 pts.vol. based on 1pt.wt. of the alpha-acetyl-gamma-butyrolactone. 5-Bromo-2-pentanone is an important synthetic intermediate for 5-bromo-2-pentanone ketal derivative which is a starting raw material for benzindane derivatives useful as pharmaceuticals.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、医農薬の合成中間体と
して有用な５−ブロモ−２−ペンタノンの製法に関する
ものである。TECHNICAL FIELD The present invention relates to a process for producing 5-bromo-2-pentanone which is useful as a synthetic intermediate for medicines and agricultural chemicals.

【０００２】[0002]

【従来技術の説明】５−ブロモ−２−ペンタノンは、医
薬として有用なベンツインダン誘導体（エストロゲン作
用，抗蛋白同化ホルモン作用，脂質移動作用，抗向子宮
作用などを有する。）の出発原料として使用されている
５−ブロモ−２−ペンタノンケタール誘導体の重要な合
成中間体である。従来、α−アセチル−γ−ブチロラク
トンと臭化水素酸とを反応させて目的化合物である５−
ブロモ−２−ペンタノンを製造する方法としては、以下
に示すような方法が知られている。Description of the Prior Art 5-Bromo-2-pentanone is used as a starting material for a drug-useful benthindane derivative (having an estrogen action, an anabolic hormone action, a lipid transfer action, an antiuterine action, etc.). It is an important synthetic intermediate of the known 5-bromo-2-pentanone ketal derivative. Conventionally, α-acetyl-γ-butyrolactone is reacted with hydrobromic acid to give the target compound 5-
The following methods are known as methods for producing bromo-2-pentanone.

【０００３】(1) 米国特許２，３７０，３９２ α−アセチル−γ−ブチロラクトンと濃臭化水素酸とを
反応させる方法。この方法では、５頁の比較例１に示す
ように目的化合物の収率は４２％と非常に低くなり、ま
た、α−アセチル−γ−ブチロラクトンに対する臭化水
素酸の使用量は２．７倍モルと多量に使用する必要があ
る。(1) A method of reacting α-acetyl-γ-butyrolactone with concentrated hydrobromic acid in US Pat. No. 2,370,392. According to this method, as shown in Comparative Example 1 on page 5, the yield of the target compound was 42%, which was extremely low, and the amount of hydrobromic acid used was 2.7 times the amount of α-acetyl-γ-butyrolactone. It is necessary to use a large amount as a mole.

【０００４】(2) Ｃ．Ａ．，４９，８２８８ｅ（１９５
５） α−アセチル−γ−ブチロラクトンと臭化水素酸とを反
応させる方法。この方法では、沸騰条件下で臭化水素酸
中にα−アセチル−γ−ブチロラクトンを滴下して反応
させた後にスチーム蒸留することによって、目的化合物
の収率は８５％となるが、α−アセチル−γ−ブチロラ
クトンに対する臭化水素酸の使用量は２．３倍モルと多
量に使用する必要がある。(2) C.I. A. , 49, 8288e (195
5) A method of reacting α-acetyl-γ-butyrolactone with hydrobromic acid. In this method, α-acetyl-γ-butyrolactone was added dropwise to hydrobromic acid under boiling conditions to cause a reaction, and then steam distillation was performed to give a target compound yield of 85%. The amount of hydrobromic acid used with respect to -γ-butyrolactone needs to be 2.3 times as much as the molar amount.

【０００５】(3) Ｓｙｎｔｈ．Ｃｏｍｍｕｎ．，１０
（１２），８９７（１９８０） α−アセチル−γ−ブチロラクトンと臭化水素酸とを、
相間移動触媒及び水難溶性溶媒の存在下に反応させる方
法。この方法では、目的化合物の収率は８５％である
が、トリエチルベンジルアンモニウムクロライドのよう
な高価な相間移動触媒が必要であり、また、α−アセチ
ル−γ−ブチロラクトンに対する臭化水素酸の使用量は
１１．２倍モルと非常に多量に使用する必要がある。(3) Synth. Commun. , 10
(12), 897 (1980) α-acetyl-γ-butyrolactone and hydrobromic acid,
A method of reacting in the presence of a phase transfer catalyst and a poorly water-soluble solvent. In this method, the yield of the target compound is 85%, but an expensive phase transfer catalyst such as triethylbenzylammonium chloride is required, and the amount of hydrobromic acid used relative to α-acetyl-γ-butyrolactone is required. Needs to be used in a very large amount of 11.2 times mole.

【０００６】以上のように、従来の方法では、目的化合
物の収率は高くても８５％を越えず、高価な臭化水素酸
を２．３〜１１．２倍モルと多量に使用する必要がある
ことから、収率，廃酸の処理，未反応臭化水素酸の回収
と再利用などの面でさらに工業的に有利な製法が求めら
れていた。As described above, in the conventional method, the yield of the target compound does not exceed 85% at the highest, and it is necessary to use expensive hydrobromic acid in a large amount of 2.3 to 11.2 times mol. Therefore, there is a demand for a more industrially advantageous production method in terms of yield, treatment of waste acid, recovery and reuse of unreacted hydrobromic acid, and the like.

【０００７】[0007]

【発明が解決すべき課題】本発明の目的は、医農薬の合
成中間体として有用な５−ブロモ−２−ペンタノンの工
業的に優れた製法を提供することである。An object of the present invention is to provide an industrially excellent process for producing 5-bromo-2-pentanone which is useful as a synthetic intermediate for medicines and agricultural chemicals.

【０００８】[0008]

【課題を解決するための手段】本発明者らは、前記の課
題を解決するために検討した結果、高収率で，臭化水素
酸の使用割合も少なくてすむ５−ブロモ−２−ペンタノ
ンの工業的に優れた製法を見出し、本発明を完成するに
至った。即ち、本発明は、α−アセチル−γ−ブチロラ
クトンと臭化水素酸とを、硫酸存在下、水難溶性溶媒中
で反応させることを特徴とする５−ブロモ−２−ペンタ
ノンの製法に関するものである。DISCLOSURE OF THE INVENTION As a result of investigations for solving the above-mentioned problems, the present inventors have found that 5-bromo-2-pentanone which has a high yield and requires a small proportion of hydrobromic acid. The inventors have found an industrially excellent manufacturing method, and have completed the present invention. That is, the present invention relates to a method for producing 5-bromo-2-pentanone, which comprises reacting α-acetyl-γ-butyrolactone with hydrobromic acid in a poorly water-soluble solvent in the presence of sulfuric acid. .

【０００９】以下、本発明について詳細に説明する。臭
化水素酸は、好ましくは工業的に多用されているもの
（４７ｗｔ％）がよい。そして、臭化水素酸の使用量
は、α−アセチル−γ−ブチロラクトンに対して１〜２
倍モル、好ましくは１．１〜１．７倍モルがよい。硫酸
の使用量は、α−アセチル−γ−ブチロラクトンに対し
て０．５倍モル未満では少なくする程反応速度が低下す
るし，１．５倍モルを越えると多くする程反応収率が低
下するので；０．５〜１．５倍モル、好ましくは０．８
〜１．３倍モルがよい。The present invention will be described in detail below. The hydrobromic acid is preferably industrially frequently used (47 wt%). The amount of hydrobromic acid used is 1-2 with respect to α-acetyl-γ-butyrolactone.
The molar ratio is preferably double, preferably 1.1 to 1.7 times. If the amount of sulfuric acid used is less than 0.5 times the molar amount of α-acetyl-γ-butyrolactone, the reaction rate will decrease, and if it exceeds 1.5 times the molar amount, the reaction yield will decrease. So; 0.5 to 1.5 times mol, preferably 0.8
~ 1.3 times the molar amount is preferred.

【００１０】水難溶性溶媒としては、本反応に直接関与
しないものであれば特に限定されず、例えば、ベンゼ
ン，トルエン，キシレン，メチルナフタリン，石油エー
テル，リグロイン，ヘキサン，クロルベンゼン，ジクロ
ルベンゼン，塩化メチレン，クロロホルム，ジクロルエ
タン，シクロヘキサンのような塩素化された又はされて
いない芳香族, 脂肪族，脂環式の炭化水素類；前記溶媒
の混合物を挙げることができる。The poorly water-soluble solvent is not particularly limited as long as it is not directly involved in this reaction, and examples thereof include benzene, toluene, xylene, methylnaphthalene, petroleum ether, ligroin, hexane, chlorobenzene, dichlorobenzene, and chlorinated. Mention may be made of chlorinated or unchlorinated aromatic, aliphatic or cycloaliphatic hydrocarbons such as methylene, chloroform, dichloroethane, cyclohexane; mixtures of the above solvents.

【００１１】水難溶性溶媒の使用量は、α−アセチル−
γ−ブチロラクトンの１重量部に対して２容量部未満で
は少なくする程反応収率が低下するし，２０容量部を越
えると多くする程製造コストの面で好ましくないので；
２〜２０容量部、好ましくは４〜１５容量部がよい。The amount of the poorly water-soluble solvent used is α-acetyl-
If it is less than 2 parts by volume with respect to 1 part by weight of γ-butyrolactone, the reaction yield decreases as it decreases, and if it exceeds 20 parts by volume, the production cost decreases as the amount increases.
The amount is 2 to 20 parts by volume, preferably 4 to 15 parts by volume.

【００１２】反応温度は、室温〜５０℃が好ましい。反
応時間は、前記の各使用原料の濃度、反応温度によって
変化するが；通常１〜２４時間である。以上のようにし
て製造された５−ブロモ−２−ペンタノンは、反応終了
後、抽出，洗浄，濃縮，蒸留などの通常の後処理を行う
ことによって容易に単離，精製することができる。The reaction temperature is preferably room temperature to 50 ° C. The reaction time varies depending on the concentration of each raw material used and the reaction temperature, but is usually 1 to 24 hours. The 5-bromo-2-pentanone produced as described above can be easily isolated and purified by subjecting it to usual post-treatments such as extraction, washing, concentration and distillation after completion of the reaction.

【００１３】[0013]

【実施例】以下、本発明を実施例及び比較例によって具
体的に説明する。なお、これらの実施例は、本発明の範
囲を限定するものではない。 実施例１ α−アセチル−γ−ブチロラクトン（１２．８ｇ、１０
０ｍｍｏｌ）と塩化メチレン（１２８ｍｌ）との混合溶
液に、室温下、臭化水素酸（４７ｗｔ％を１７．４ｍ
ｌ、１５０ｍｍｏｌ）、次いで、硫酸（９６ｗｔ％を１
０．２ｇ、９９．８ｍｍｏｌ）の順序で、炭酸ガスの発
泡が激しくならないように注意しつつ攪拌しながら滴下
した。そして、滴下終了後、内温４０℃で１０時間攪拌
した。反応終了後、反応液を室温まで冷却し、有機層と
水層とに分液し、この水層に塩化メチレン（１０ｍｌ）
を加えて抽出し、有機層を得た。EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples. It should be noted that these examples do not limit the scope of the present invention. Example 1 α-acetyl-γ-butyrolactone (12.8 g, 10
0 mmol) and methylene chloride (128 ml) in a mixed solution of hydrobromic acid (47 wt% is 17.4 m) at room temperature.
1, 150 mmol), then sulfuric acid (96 wt% to 1
0.2 g, 99.8 mmol) was added in this order with stirring, taking care not to make the bubbling of carbon dioxide gas violent. After the dropping was completed, the mixture was stirred at an internal temperature of 40 ° C for 10 hours. After the completion of the reaction, the reaction solution was cooled to room temperature, separated into an organic layer and an aqueous layer, and methylene chloride (10 ml) was added to the aqueous layer.
Was added and extracted to obtain an organic layer.

【００１４】得られた両方の有機層を一つに合わせ、こ
れを飽和重曹水（１０ｍｌ）、飽和食塩水（１０ｍｌ）
の順序で洗浄した後に、無水硫酸マグネシウムで乾燥
し、濾過し、減圧濃縮することによって黄色油状の残渣
を得、さらに、これを真空蒸留することによって無色透
明の油状物質を得た。収率は、前記の乾燥濾液に内部標
準物質を加えてガスクロマトグラフィーを行った結果、
９６．５％であった。無色透明の油状物質は、次に示す
沸点，ＩＲ，ＰＭＲで目的化合物の５−ブロモ−２−ペ
ンタノンであることを確認できた。Both of the obtained organic layers were combined into one, which was saturated sodium hydrogen carbonate solution (10 ml) and saturated saline solution (10 ml).
After being washed in this order, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure to obtain a yellow oily residue, which was further vacuum distilled to obtain a colorless transparent oily substance. The yield is the result of performing gas chromatography by adding an internal standard substance to the dried filtrate,
It was 96.5%. It was confirmed that the colorless and transparent oily substance was the target compound 5-bromo-2-pentanone by the following boiling points, IR and PMR.

【００１５】沸点：７２℃／１３ｍｍＨｇ ＩＲ（液膜法 ｃｍ-1）：１７１５（Ｃ＝Ｏ） ＰＭＲ（ＣＤＣｌ3 、δ）：２．１３（ｑｕ，Ｊ＝８Ｈ
ｚ，２Ｈ），２．１５（ｓ，３Ｈ），２．６５（ｔ，Ｊ
＝８Ｈｚ，２Ｈ），３．４５（ｔ，Ｊ＝８Ｈｚ，２Ｈ）Boiling point: 72 ° C./13 mmHg IR (liquid film method cm −1 ): 1715 (C═O) PMR (CDCl 3 , δ): 2.13 (qu, J = 8H
z, 2H), 2.15 (s, 3H), 2.65 (t, J
= 8Hz, 2H), 3.45 (t, J = 8Hz, 2H)

【００１６】実施例２ 臭化水素酸（４７ｗｔ％を１３．９ｍｌ、１２０ｍｍｏ
ｌ）、硫酸（９６ｗｔ％を１０．２ｇ、９９．８ｍｍｏ
ｌ）及びトルエン（６４ｍｌ）の混合液に、室温下、α
−アセチル−γ−ブチロラクトン（１２．８ｇ、１００
ｍｍｏｌ）を炭酸ガスの発泡が激しくならないように注
意しつつ攪拌しながら滴下した。そして、滴下終了後、
内温４０℃で１０時間攪拌した。Example 2 Hydrobromic acid (47 wt% was 13.9 ml, 120 mmo
l), sulfuric acid (96 wt% 10.2 g, 99.8 mmo
1) and toluene (64 ml) at room temperature under a
-Acetyl-γ-butyrolactone (12.8 g, 100
(mmol) was added dropwise with stirring while paying attention not to make the bubbling of carbon dioxide gas violent. And after the dropping is completed,
The mixture was stirred at an internal temperature of 40 ° C for 10 hours.

【００１７】反応終了後、反応液を室温まで冷却し、有
機層と水層とに分液し、この水層にトルエン（１０ｍ
ｌ）を加えて抽出し、有機層を得た。得られた両方の有
機層を一つに合わせ、以下、実施例１と同様にして目的
化合物を得た（収率は９４．８％）。After the reaction was completed, the reaction solution was cooled to room temperature and separated into an organic layer and an aqueous layer.
l) was added and extracted to obtain an organic layer. Both of the obtained organic layers were combined to obtain the desired compound (yield 94.8%) in the same manner as in Example 1.

【００１８】比較例１ 引例(1) の方法に準じて目的化合物を合成した。α−ア
セチル−γ−ブチロラクトン（１２．８ｇ、１００ｍｍ
ｏｌ）と臭化水素酸（４７ｗｔ％を３１．４ｍｌ、２７
０ｍｍｏｌ）とを１５〜２０℃で１２時間攪拌した。反
応終了後、塩化メチレン（６４ｍｌ）を加えて有機層と
水層とに分液し、この水層に塩化メチレン（１０ｍｌ）
を加えて抽出し、有機層を得た。得られた両方の有機層
を一つに合わせ、以下、実施例１と同様にして目的化合
物を得た（収率は４２．３％）。Comparative Example 1 A target compound was synthesized according to the method of Reference (1). α-Acetyl-γ-butyrolactone (12.8 g, 100 mm
ol) and hydrobromic acid (47 wt% 31.4 ml, 27
0 mmol) was stirred at 15 to 20 ° C. for 12 hours. After completion of the reaction, methylene chloride (64 ml) was added to separate into an organic layer and an aqueous layer, and methylene chloride (10 ml) was added to the aqueous layer.
Was added and extracted to obtain an organic layer. Both of the obtained organic layers were put together to obtain the target compound in the same manner as in Example 1 (yield: 42.3%).

【００１９】比較例２ α−アセチル−γ−ブチロラクトン（１２．８ｇ、１０
０ｍｍｏｌ）と塩化メチレン（１２８ｍｌ）との混合液
に、室温下、臭化水素酸（４７ｗｔ％を１３．９ｍｌ、
１２０ｍｍｏｌ）を炭酸ガスの発泡が激しくならないよ
うに注意しつつ攪拌しながら滴下した。そして、滴下終
了後、内温４０℃で３６時間攪拌した。以下、実施例１
と同様にして目的化合物を得た（収率は７２．３％）。Comparative Example 2 α-Acetyl-γ-butyrolactone (12.8 g, 10
0 mmol) and methylene chloride (128 ml) at room temperature, hydrobromic acid (47 wt% 13.9 ml,
120 mmol) was added dropwise with stirring while paying attention not to make the bubbling of carbon dioxide gas violent. After the dropping was completed, the mixture was stirred at an internal temperature of 40 ° C. for 36 hours. Hereinafter, Example 1
The target compound was obtained in the same manner as described above (yield: 72.3%).

【００２０】[0020]

【発明の効果】本発明によれば、医農薬の合成中間体と
して重要な５−ブロモ−２−ペンタノンを、高収率で，
かつ高価な臭化水素酸の使用割合を減らして生産するこ
とができる。INDUSTRIAL APPLICABILITY According to the present invention, 5-bromo-2-pentanone, which is important as a synthetic intermediate for medicines and agricultural chemicals, can be obtained in high yield.
In addition, it is possible to reduce the amount of expensive hydrobromic acid used and to produce it.

───────────────────────────────────────────────────── フロントページの続き (72)発明者 橋本 淳一 山口県宇部市大字小串1978番地の５ 宇部 興産株式会社宇部研究所内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Junichi Hashimoto 5 1978, Kogushi, Ube City, Ube Yamaguchi Prefecture 5 Ube Kosan Co., Ltd. Ube Laboratory

Claims (1)

【特許請求の範囲】[Claims] 【請求項１】 α−アセチル−γ−ブチロラクトンと臭
化水素酸とを、硫酸存在下、水難溶性溶媒中で反応させ
ることを特徴とする５−ブロモ−２−ペンタノンの製
法。1. A method for producing 5-bromo-2-pentanone, which comprises reacting α-acetyl-γ-butyrolactone with hydrobromic acid in the presence of sulfuric acid in a poorly water-soluble solvent.
JP25316293A 1993-10-08 1993-10-08 Production of 5-bromo-2-pentanone Pending JPH07109244A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP25316293A JPH07109244A (en) 1993-10-08 1993-10-08 Production of 5-bromo-2-pentanone

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP25316293A JPH07109244A (en) 1993-10-08 1993-10-08 Production of 5-bromo-2-pentanone

Publications (1)

Publication Number Publication Date
JPH07109244A true JPH07109244A (en) 1995-04-25

Family

ID=17247401

Family Applications (1)

Application Number Title Priority Date Filing Date
JP25316293A Pending JPH07109244A (en) 1993-10-08 1993-10-08 Production of 5-bromo-2-pentanone

Country Status (1)

Country Link
JP (1) JPH07109244A (en)

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