JP2006265196A - Method for separating methyl isobutyl ketone and benzylamine - Google Patents
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Abstract
Description
本発明は、メチルイソブチルケトンとベンジルアミンを分離する方法に関する。 The present invention relates to a method for separating methyl isobutyl ketone and benzylamine.
ベンジルアミンは、アミノ基を導入するための求核剤として有用であり、例えば、米国特許第２４８９２３２号明細書（特許文献１）やジャーナル・オブ・ザ・アメリカン・ケミカル・ソサイエティ（Journal of the American Chemical Society）、（米国）、１９７８年、第１００巻、ｐ．１５５８−１５６３（非特許文献１）には、２，３−ジブロモコハク酸をエタノール溶媒中でベンジルアミンと反応させることにより、ビオチン中間体の２，３−ビス（ベンジルアミノ）コハク酸を製造することが記載されている。 Benzylamine is useful as a nucleophilic agent for introducing an amino group, and includes, for example, US Pat. No. 2,489,232 (Patent Document 1) and Journal of the American Chemical Society (Journal of the American Society). Chemical Society), (USA), 1978, Vol. 100, p. 1558-1563 (Non-patent Document 1) produces 2,3-bis (benzylamino) succinic acid as a biotin intermediate by reacting 2,3-dibromosuccinic acid with benzylamine in an ethanol solvent. It is described.
また、メチルイソブチルケトン（４−メチル−２−ペンタノン）は、水と分液可能なケトン溶媒として有用であり、先に本発明者は、メチルイソブチルケトンを反応溶媒に用いて上記反応を行うことを提案している（特願２００５−５０６６７号）。この方法によれば、反応混合物から塩基性水溶液により２，３−ビス（ベンジルアミノ）コハク酸を抽出することができると共に、抽出残液の油層としてメチルイソブチルケトンと未反応のベンジルアミンの混合物を回収することができる。 Further, methyl isobutyl ketone (4-methyl-2-pentanone) is useful as a ketone solvent that can be separated from water, and the present inventor first performs the above reaction using methyl isobutyl ketone as a reaction solvent. (Japanese Patent Application No. 2005-50667). According to this method, 2,3-bis (benzylamino) succinic acid can be extracted from the reaction mixture with a basic aqueous solution, and a mixture of methyl isobutyl ketone and unreacted benzylamine is used as an oil layer of the extraction residual liquid. It can be recovered.
上記抽出残液の如きメチルイソブチルケトンとベンジルアミンの混合物をメチルイソブチルケトンとベンジルアミンとに分離する方法としては、例えば、該混合物から酸性水溶液によりベンジルアミンを抽出し、この酸性抽出液を塩基で中和してベンジルアミンを回収すると共に、抽出残液の油層としてメチルイソブチルケトンを回収するというような、一般的な中性物質と塩基性物質の分離方法が採用しうるが、抽出及び中和の各操作に加え、中和排水の処理も必要となるため、操作が煩雑になり、それに伴うコストや設備面での負担も大きい。一方、メチルイソブチルケトンとベンジルアミンを蒸留により分離できれば、上記の如き操作の煩雑さを解消できて有利であるが、上記混合物を単純に蒸留に付すと、メチルイソブチルケトンとベンジルアミンの脱水縮合によりイミンが生成して、分離が困難となる。そこで、本発明の目的は、メチルイソブチルケトンとベンジルアミンを、イミンの形成が抑制された条件下に操作性良く分離しうる方法を提供することにある。 As a method for separating a mixture of methyl isobutyl ketone and benzylamine, such as the above extraction residue, into methyl isobutyl ketone and benzylamine, for example, benzylamine is extracted from the mixture with an acidic aqueous solution, and this acidic extract is extracted with a base. A general method for separating neutral and basic substances, such as recovering benzylamine and neutralizing methyl isobutyl ketone as an oil layer of the extraction residual liquid, can be adopted. In addition to the above operations, it is also necessary to treat the neutralized waste water, which makes the operation complicated, resulting in a large cost and equipment burden. On the other hand, if methyl isobutyl ketone and benzylamine can be separated by distillation, it is advantageous to eliminate the complexity of the operation as described above. However, if the above mixture is simply subjected to distillation, dehydration condensation of methyl isobutyl ketone and benzylamine will result. Imine is formed and separation becomes difficult. Therefore, an object of the present invention is to provide a method capable of separating methyl isobutyl ketone and benzylamine with good operability under the conditions in which the formation of imine is suppressed.
本発明者らは鋭意研究を行った結果、上記混合物を水と混合してなる油水二相系の混合物を蒸留に付すことにより、上記目的を達成できることを見出し、本発明を完成するに至った。すなわち、本発明は、メチルイソブチルケトンとベンジルアミンの混合物を水と混合し、得られた油水二相系の混合物を蒸留することにより、メチルイソブチルケトンとベンジルアミンを分離する方法を提供するものである。 As a result of intensive studies, the present inventors have found that the above object can be achieved by subjecting a mixture of an oil-water two-phase system obtained by mixing the above mixture with water to distillation, and have completed the present invention. . That is, the present invention provides a method for separating methyl isobutyl ketone and benzylamine by mixing a mixture of methyl isobutyl ketone and benzylamine with water and distilling the resulting oil-water two-phase mixture. is there.
本発明によれば、メチルイソブチルケトンとベンジルアミンを操作性良く分離することができる。 According to the present invention, methyl isobutyl ketone and benzylamine can be separated with good operability.
本発明で分離の対象とされるメチルイソブチルケトンとベンジルアミンの混合物としては、例えば、前述の如き、２，３−ジブロモコハク酸をメチルイソブチルケトン溶媒中でベンジルアミンと反応させ、得られた反応混合物から塩基性水溶液により２，３−ビス（ベンジルアミノ）コハク酸を抽出した後の抽出残液である油層が挙げられるが、これに限定されるものではない。該混合物におけるメチルイソブチルケトンとベンジルアミンの含有割合は任意であるが、通常、メチルイソブチルケトン／ベンジルアミンの重量割合で１０／９０〜９０／１０程度である。また、該混合物には、メチルイソブチルケトン及びベンジルアミン以外の成分、例えば水などが含まれていてもよい。 As a mixture of methyl isobutyl ketone and benzylamine to be separated in the present invention, for example, as described above, 2,3-dibromosuccinic acid is reacted with benzylamine in a methyl isobutyl ketone solvent, and the reaction obtained Although the oil layer which is the extraction residual liquid after extracting 2, 3-bis (benzylamino) succinic acid from a mixture with basic aqueous solution is mentioned, It is not limited to this. The content ratio of methyl isobutyl ketone and benzylamine in the mixture is arbitrary, but is usually about 10/90 to 90/10 by weight ratio of methyl isobutyl ketone / benzylamine. In addition, the mixture may contain components other than methyl isobutyl ketone and benzylamine, such as water.
本発明では、上記のメチルイソブチルケトンとベンジルアミンの混合物を水と混合し、得られた油水二相系の混合物を蒸留することにより、メチルイソブチルケトンとベンジルアミンを分離する。この蒸留により、具体的には、低沸点側の留出液として、メチルイソブチルケトンと水の混合物を得ることができると共に、高沸点側の留出液として、又は缶出液として、ベンジルアミンを得ることができる。なお、ベンジルアミンを留出液として得るか、缶出液として得るかは、高沸点不純物の有無や量などに応じて、選択される。 In the present invention, methyl isobutyl ketone and benzylamine are separated by mixing the mixture of methyl isobutyl ketone and benzylamine with water and distilling the resulting oil-water two-phase mixture. Specifically, by this distillation, a mixture of methyl isobutyl ketone and water can be obtained as a distillate on the low boiling point side, and benzylamine can be used as a distillate on the high boiling point side or as a bottoms. Obtainable. Whether benzylamine is obtained as a distillate or as a bottom is selected depending on the presence and amount of high-boiling impurities.
水の使用量は、あまり少ないと、メチルイソブチルケトンとベンジルアミンの脱水縮合によるイミンの生成を抑制し難くなり、あまり多いと、留出水中にベンジルアミンを損失し易くなるので、メチルイソブチルケトンに対し、通常０．２〜５重量倍、好ましくは０．５〜２重量倍程度である。 If the amount of water used is too small, it will be difficult to suppress the formation of imine due to dehydration condensation of methyl isobutyl ketone and benzylamine, and if too large, benzylamine will be easily lost in the distilled water. On the other hand, it is usually about 0.2 to 5 times by weight, preferably about 0.5 to 2 times by weight.
蒸留の方式は適宜選択され、例えば、単蒸留であってもよいし、精留であってもよく、また、バッチ式蒸留であってもよいし、連続式蒸留であってもよい。また、蒸留の条件も適宜選択されるが、１〜５０ｋＰａ程度の減圧下に行うのが望ましい。 The distillation method is appropriately selected. For example, simple distillation, rectification, batch distillation or continuous distillation may be used. Moreover, although the conditions of distillation are also selected suitably, it is desirable to carry out under reduced pressure of about 1-50 kPa.
留出液として得られたメチルイソブチルケトンと水の混合物は、油水分離によりメチルイソブチルケトンからなる油層と水層とに分離することができ、このメチルイソブチルケトンからなる油層は、さらに蒸留や脱水などの精製操作に付してもよい。また、留出液又は缶出液として得られたベンジルアミンも、さらに蒸留や脱水などの精製操作に付してもよい。 The mixture of methyl isobutyl ketone and water obtained as a distillate can be separated into an oil layer and an aqueous layer made of methyl isobutyl ketone by oil-water separation. This oil layer made of methyl isobutyl ketone is further distilled, dehydrated, etc. You may attach | subject to refinement | purification operation of. Further, benzylamine obtained as a distillate or a bottoms may also be subjected to a purification operation such as distillation or dehydration.
以下、本発明の実施例を示すが、本発明はこれらによって限定されるものではない。例中、含有量を表す％は、特記ない限り重量基準である。 Examples of the present invention will be described below, but the present invention is not limited thereto. In the examples,% representing the content is based on weight unless otherwise specified.
参考例１（メチルイソブチルケトンとベンジルアミンの混合物の取得）
２Ｌナスフラスコに、２，３−ジブロモコハク酸２００ｇとメチルイソブチルケトン４００ｇを入れて攪拌した。この中に、内温を４０℃以下に保ちながら、ベンジルアミン５３０ｇを１時間かけて滴下した後、８０℃で２時間、次いで１００℃で２時間、保持した。得られた反応混合物に、６０℃で４９％水酸化カリウム水溶液３６０ｇと水１５０ｇを添加して混合後、油層と水層とに分離し、次いで水層をメチルイソブチルケトン２００ｇで２回洗浄して、２，３−ビス（ベンジルアミノ）コハク酸１８．３％（１７９ｇ、収率７７％）を含む塩基性水溶液９７８ｇを得た。
Reference Example 1 (Acquisition of a mixture of methyl isobutyl ketone and benzylamine)
In a 2 L eggplant flask, 200 g of 2,3-dibromosuccinic acid and 400 g of methyl isobutyl ketone were added and stirred. Into this, 530 g of benzylamine was dropped over 1 hour while keeping the internal temperature at 40 ° C. or lower, and then kept at 80 ° C. for 2 hours and then at 100 ° C. for 2 hours. To the obtained reaction mixture, 360 g of a 49% potassium hydroxide aqueous solution and 150 g of water were added at 60 ° C. and mixed, then separated into an oil layer and an aqueous layer, and then the aqueous layer was washed twice with 200 g of methyl isobutyl ketone. 978 g of a basic aqueous solution containing 18.3% of 2,3-bis (benzylamino) succinic acid (179 g, yield 77%) was obtained.
また、上で分離した油層と、水層の洗浄（２回）に使用したメチルイソブチルケトンを混合して、メチルイソブチルケトンとベンジルアミンの混合物１０８３ｇを回収した。この混合物中のベンジルアミンの含有量は３６％（３９０ｇ）であり、残部の６４％は溶解分の水を除いて略メチルイソブチルケトンであった。 Further, the oil layer separated above and methyl isobutyl ketone used for washing (twice) of the aqueous layer were mixed to recover 1083 g of a mixture of methyl isobutyl ketone and benzylamine. The content of benzylamine in this mixture was 36% (390 g), and the remaining 64% was substantially methyl isobutyl ketone except for the water of dissolved components.
実施例１
参考例１で得られたメチルイソブチルケトンとベンジルアミンの混合物１５０ｇを、水１００ｇと混合し、さらにメチルイソブチルケトン１５ｇと混合した。得られた油水二相系の混合物を、１５０Ｔｏｒｒ（２０ｋＰａ）の減圧下に、加熱浴の温度を室温から８０℃まで昇温して蒸留し、メチルイソブチルケトンと水からなる留出液１８４ｇを得、この留出液を油水分離して、メチルイソブチルケトンからなる油層１０２ｇ〔メチルイソブチルケトンの純度９８％（純分１００ｇ）、回収率８８％（参考例１で得られたメチルイソブチルケトンとベンジルアミンの混合物中のメチルイソブチルケトンの含有量を６４％（ベンジルアミンの残部）として計算した値；以下同じ）〕を得た。次いで、未留出分を引き続き、２０Ｔｏｒｒ（２．６ｋＰａ）の減圧下に、加熱浴の温度を８０℃から１２０℃まで昇温して蒸留し、ベンジルアミンからなる留出液３６ｇ〔ベンジルアミンの純度９３％（純分３３ｇ）、回収率６２％〕を得た。
Example 1
150 g of a mixture of methyl isobutyl ketone and benzylamine obtained in Reference Example 1 was mixed with 100 g of water and further mixed with 15 g of methyl isobutyl ketone. The resulting oil / water two-phase mixture was distilled under a reduced pressure of 150 Torr (20 kPa) by raising the temperature of the heating bath from room temperature to 80 ° C. to obtain 184 g of a distillate composed of methyl isobutyl ketone and water. The distillate was separated into oil and water, and 102 g of an oil layer consisting of methyl isobutyl ketone [purity of methyl isobutyl ketone 98% (pure content 100 g), recovery rate 88% (methyl isobutyl ketone and benzylamine obtained in Reference Example 1) The content of methyl isobutyl ketone in the mixture was calculated as 64% (the balance of benzylamine; the same applies hereinafter)]. Subsequently, the undistilled fraction was distilled under a reduced pressure of 20 Torr (2.6 kPa) while raising the temperature of the heating bath from 80 ° C. to 120 ° C., and 36 g of distillate consisting of benzylamine [benzylamine 93% purity (33 g pure), 62% recovery].
比較例１
参考例１で得られたメチルイソブチルケトンとベンジルアミンの混合物２００ｇを、２０％塩酸１５２ｇと混合し、さらにメチルイソブチルケトン２５ｇと混合した後、油水分離した。得られた油層８８．３ｇを、１５０Ｔｏｒｒ（２０ｋＰａ）の減圧下に、加熱浴の温度を室温から８０℃まで昇温して蒸留し、メチルイソブチルケトンからなる留出液８１ｇ〔メチルイソブチルケトンの純度９８％（純分７９ｇ）、回収率５２％〕を得た。また、上記油水分離により得られた水層を、１５０Ｔｏｒｒ（２０ｋＰａ）の減圧下に、加熱浴の温度を室温から８０℃まで昇温して蒸留し、メチルイソブチルケトンと水からなる留出液９０ｇを得、この留出液を油水分離して、メチルイソブチルケトンからなる油層６２ｇ〔メチルイソブチルケトンの純度９７％（純分６０ｇ）、回収率３９％〕を得た。次いで、未留出分を、４８％水酸化ナトリウム水溶液８４ｇと混合した後、油水分離し、得られた油層を、２０Ｔｏｒｒ（２．６ｋＰａ）の減圧下に、加熱浴の温度を室温から１２０℃まで昇温して蒸留し、ベンジルアミンからなる留出液５２ｇ〔ベンジルアミンの純度９４％（純分４９ｇ）、回収率６８％〕を得た。
Comparative Example 1
200 g of the mixture of methyl isobutyl ketone and benzylamine obtained in Reference Example 1 was mixed with 152 g of 20% hydrochloric acid, and further mixed with 25 g of methyl isobutyl ketone, followed by oil-water separation. 88.3 g of the obtained oil layer was distilled under reduced pressure of 150 Torr (20 kPa) while raising the temperature of the heating bath from room temperature to 80 ° C., and 81 g of a distillate consisting of methyl isobutyl ketone [purity of methyl isobutyl ketone] 98% (pure content 79 g), recovery rate 52%]. The aqueous layer obtained by the oil-water separation was distilled under a reduced pressure of 150 Torr (20 kPa) by raising the temperature of the heating bath from room temperature to 80 ° C., and 90 g of distillate consisting of methyl isobutyl ketone and water was distilled. This distillate was separated into oil and water to obtain 62 g of an oil layer composed of methyl isobutyl ketone (purity of methyl isobutyl ketone 97% (pure content 60 g), recovery rate 39%). Subsequently, the distillate was mixed with 84 g of a 48% aqueous sodium hydroxide solution, followed by oil-water separation. The resulting oil layer was heated under a reduced pressure of 20 Torr (2.6 kPa) and the temperature of the heating bath was changed from room temperature to 120 ° C. The mixture was heated and distilled to obtain 52 g of a distillate composed of benzylamine (benzylamine purity 94% (pure content 49 g), recovery rate 68%).
比較例２
参考例１で得られたメチルイソブチルケトンとベンジルアミンの混合物２５０ｇを、１５０Ｔｏｒｒ（２０ｋＰａ）の減圧下に、加熱浴の温度を室温から８０℃まで昇温して蒸留し、メチルイソブチルケトンと水からなる留出液を得、この留出液を油水分離して、メチルイソブチルケトンからなる油層９１ｇ〔メチルイソブチルケトンの純度９５％（純分８６ｇ）、回収率５４％〕を得た。次いで、未留出物を引き続き、２０Ｔｏｒｒ（２．６ｋＰａ）の減圧下に、加熱浴の温度を８０℃から１２０℃まで昇温して蒸留したが、ベンジルアミンからなる留出液は得られなかった。さらに、未留出物を引き続き、２０Ｔｏｒｒ（２．６ｋＰａ）の減圧下に、加熱浴の温度を１２０℃から１５０℃まで昇温して蒸留したところ、留出液１８ｇが得られた。この留出液は、質量分析の結果、メチルイソブチルケトンとベンジルアミンが脱水縮合したイミンであることが分かった。
Comparative Example 2
250 g of a mixture of methyl isobutyl ketone and benzylamine obtained in Reference Example 1 was distilled under a reduced pressure of 150 Torr (20 kPa) by raising the temperature of the heating bath from room temperature to 80 ° C., and from methyl isobutyl ketone and water. This distillate was obtained, and this distillate was separated into oil and water to obtain 91 g of an oil layer consisting of methyl isobutyl ketone (purity of methyl isobutyl ketone 95% (pure content 86 g), recovery rate 54%). Subsequently, the distillate was continuously distilled under a reduced pressure of 20 Torr (2.6 kPa) while raising the temperature of the heating bath from 80 ° C. to 120 ° C., but a distillate composed of benzylamine was not obtained. It was. Further, when the undistilled product was distilled under a reduced pressure of 20 Torr (2.6 kPa) while raising the temperature of the heating bath from 120 ° C. to 150 ° C., 18 g of a distillate was obtained. As a result of mass spectrometry, the distillate was found to be imine obtained by dehydration condensation of methyl isobutyl ketone and benzylamine.
実施例２
メチルイソブチルケトン７５ｇとベンジルアミン７５ｇを混合して、メチルイソブチルケトンとベンジルアミンの混合物１５０ｇを調製し、これを水７０ｇと混合した。得られた油水二相系の混合物を、１５０Ｔｏｒｒ（２０ｋＰａ）の減圧下に、加熱浴の温度を室温から８０℃まで昇温して蒸留し、メチルイソブチルケトンと水からなる留出液１４６ｇを得、この留出液を油水分離して、メチルイソブチルケトンからなる油層７３ｇ〔メチルイソブチルケトンの純度９７％（純分７１ｇ）、回収率９４％〕を得た。次いで、未留出分を引き続き、２０Ｔｏｒｒ（２．６ｋＰａ）の減圧下に、加熱浴の温度を８０℃から１２０℃まで昇温して蒸留し、ベンジルアミンからなる留出液７３ｇ〔ベンジルアミンの純度９８％（純分７２ｇ）、回収率９６％〕を得た。
Example 2
75 g of methyl isobutyl ketone and 75 g of benzylamine were mixed to prepare 150 g of a mixture of methyl isobutyl ketone and benzylamine, which was mixed with 70 g of water. The resulting oil / water two-phase mixture was distilled under a reduced pressure of 150 Torr (20 kPa) by raising the temperature of the heating bath from room temperature to 80 ° C. to obtain 146 g of a distillate composed of methyl isobutyl ketone and water. The distillate was separated into oil and water to obtain 73 g of an oil layer composed of methyl isobutyl ketone (purity of methyl isobutyl ketone 97% (pure content 71 g), recovery rate 94%). Subsequently, the undistilled portion was continuously distilled under reduced pressure of 20 Torr (2.6 kPa) while raising the temperature of the heating bath from 80 ° C. to 120 ° C., and 73 g of distillate consisting of benzylamine [benzylamine Purity 98% (pure content 72 g), recovery rate 96%].
Claims (3)
The method according to claim 1, wherein a distillate containing methyl isobutyl ketone and a distillate containing benzylamine are obtained by the distillation.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102351725A (en) * | 2011-07-27 | 2012-02-15 | 安徽省郎溪县联科实业有限公司 | Process for synthesizing N-benzyl-3-(benzylamino)aspartic acid |
| CN108997142A (en) * | 2018-08-20 | 2018-12-14 | 浙江建业化工股份有限公司 | Remove the method that ketone is remained in ketone method production fatty amine |
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2005
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102351725A (en) * | 2011-07-27 | 2012-02-15 | 安徽省郎溪县联科实业有限公司 | Process for synthesizing N-benzyl-3-(benzylamino)aspartic acid |
| CN108997142A (en) * | 2018-08-20 | 2018-12-14 | 浙江建业化工股份有限公司 | Remove the method that ketone is remained in ketone method production fatty amine |
| CN108997142B (en) * | 2018-08-20 | 2021-01-12 | 浙江建业化工股份有限公司 | Method for removing residual ketone in production of fatty amine by ketone method |
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