JP4482280B2 - Method for purifying and producing 2,5-bis (aminomethyl) -1,4-dithiane compound - Google Patents

Description

【０００９】
（式中、Ｒ^１及びＲ^２は、それぞれ独立して水素原子又はＣ１〜Ｃ６アルキル基を表す。）で表される化合物及び不純物を含有する水溶液のｐＨ値を１０．５〜１１．５に調整し、不純物を有機溶媒により抽出して除去する工程と、得られた水溶液のｐＨ値を１２．５〜１３．５に調整して、前記（１）で表される化合物を有機溶媒により抽出する工程とを有する式（１）で表される化合物の精製方法を提供する。
また、本発明は第２に、式（２）
【００１０】
【化５】

【００１１】
（式中、Ｒ^１及びＲ^２は、それぞれ独立して水素原子又はＣ１〜Ｃ６アルキル基を表し、Ｘ^１及びＸ^２は、それぞれ独立してハロゲン原子を表す。）
で表される化合物にアンモニアを反応させて、式（１）
【００１２】
【化６】

【００１３】
（式中、Ｒ^１及びＲ^２は、それぞれ独立して水素原子又はＣ１〜Ｃ６アルキル基を表す。）で表される化合物を含有する反応混合物を得る工程と、該混合物の水溶液のｐＨ値を１０．５〜１１．５に調整し、前記水溶液に含まれる不純物を有機溶媒により抽出して除去する工程と、得られた水溶液のｐＨ値を１２．５〜１３．５に調整して、前記式（１）で表される化合物を有機溶媒により抽出する工程を有する式（１）で表される化合物の製造方法を提供する。
【００１４】
本発明によれば、減圧蒸留を行わなくても、簡便な操作によって、光学製品等の製造原料として許容できる程度に高純度な式（１）で表される化合物を得ることができる。
【００１５】
【発明の実施の形態】
本発明は、前記式（１）で表される化合物の精製方法及び製造方法である。
式（１）中、Ｒ^１及びＲ^２は、それぞれ独立して水素原子；メチル、エチル、ｎ−プロピル、イソプロピル、ｎ−ブチル、イソブチル、ｓｅｃ−ブチル、ｔ−ブチル基等のＣ１〜Ｃ６アルキル基を表す。
【００１６】
式（１）で表される化合物の具体例としては、２，５−ビス（アミノメチル）−１，４−ジチアン、２，５−ビス（アミノメチル）−２，５−ジメチル−１，４−ジチアン、２，５−ビス（アミノメチル）−２，５−ジエチル−１，４−ジチアン、２，５−ビス（アミノメチル）−２，５−ジ−ｎ−プロピル−１，４−ジチアン、２，５−ビス（アミノメチル）−２，５−ジ−ｎ−ブチル−１，４−ジチアン等が挙げられる。
【００１７】
前記式（１）で表される化合物の製造方法として、具体的には、前記式（２）で表される化合物とアンモニアを反応させる方法を例示することができる。
式（２）中、Ｒ^１及びＲ^２は前記と同じ意味を表し、同様の具体例を例示することができる。Ｘ^１及びＸ^２は、それぞれ独立して、塩素原子、臭素原子、ヨウ素原子等のハロゲン原子を表す。
式（２）で表される化合物の製造方法としては、例えば、Ｊ．Ｏｒｇ．Ｃｈｅｍ．，第３４巻，３３８９〜３３９１頁（１９６９年）に記載の方法等が挙げられる。
【００１８】
式（２）で表される化合物とアンモニアとの反応に用いられる溶媒は特に限定されないが、アンモニアを溶解する溶媒が好ましく、具体的には、水；メタノール、エタノール等のアルコール類；塩化メチレン、クロロホルム等のハロゲン化炭化水素類等が挙げられる。これらの溶媒は１種単独で、又は２種以上を混合して用いることができる。溶媒の使用量は特に制限されないが、式（２）で表される化合物１重量部に対して、通常１〜１００重量部、好ましくは１〜２０重量部の範囲である。
【００１９】
アンモニアは、アンモニア水又はアンモニアガスとして反応系に供給することができ、両者を併用して用いることもできる。アンモニアの使用量は、式（２）で表される化合物１モルに対して過剰であれば特に制限されないが、通常１〜８０倍モル、好ましくは１０〜６０倍モル、より好ましくは２０〜６０倍モルの範囲である。
【００２０】
また、式（１）で表される化合物とアンモニアとの反応は触媒の存在下に行うのが、反応効率を向上させる上で好ましい。用いることができる触媒としては、例えば、塩化第一銅、塩化第二銅、塩化亜鉛、酸化亜鉛等が挙げられる。触媒の使用量に特に制限はないが、式（２）で表される化合物１モルに対して、通常０．０１モル重量％〜３０モル重量％の範囲である。
【００２１】
反応は、通常３０〜１５０℃、好ましくは４０〜１２０℃で円滑に進行する。反応温度を３０℃以下にすると反応が遅くなる一方、反応温度が１５０℃を超えると反応圧が高くなり好ましくない。
【００２２】
本発明は、以上のようにして得られた反応混合物から、ｐＨ値の差により、抽出操作のみによって目的物を単離精製することを特徴とする。
本発明は、式（１）で表される化合物を含有する水溶液のｐＨ値を、通常１０〜１２、好ましくは１０．５〜１１．５の範囲に調整し、次いで、不純物を有機溶媒により抽出して除去する工程を有する。すなわち、式（１）で表される化合物と不純物を含有する水溶液を所定のｐＨ値に設定することで、不純物と式（１）で表される化合物の酸性度の違いを利用して、不純物のみを水層から有機層へ選択的に抽出して除去することができる。
【００２３】
この工程においては、必要に応じて、水と相溶性を有するメタノール、エタノール等のアルコール系溶媒；アセトン、テトラヒドロフラン等のエーテル系溶媒等を水と併用することができる。また、水に不溶性の不純物については、予め少量の有機溶媒で除去しておくのが好ましい。
【００２４】
水溶液のｐＨ値は、必要に応じて水やメタノール等の溶媒を加えた後、酸又はアルカリを添加することにより所定値に調整することができる。
ｐＨ調整に用いられる酸としては、例えば、塩酸、硝酸、硫酸等が挙げられる。また、アルカリとしては、水酸化カリウム、水酸化ナトリウム、炭酸カリウム、炭酸ナトリウム、アンモニア、アンモニア水等が挙げられる。
【００２５】
酸又はアルカリの添加は、式（１）で表される化合物を含有する水溶液の急激なｐＨ変化を防止し、精密なｐＨ調整を行なう観点から溶液全体を十分に撹拌しながら少量ずつ添加して行なうのが好ましい。また、ｐＨ調整は、式（１）で表される化合物を含有する水溶液に有機溶媒を添加する前に行なっても、添加後に行なってもよい。
【００２６】
不純物の抽出に用いられる有機溶媒としては、水と混合しない有機溶媒であれば特に制限はない。具体的には、ベンゼン、トルエン、キシレン等の芳香族炭化水素類；塩化メチレン、クロロホルム、四塩化炭素等のハロゲン化炭化水素類；等を例示することができる。これらの中でも、不純物の溶解性の観点から、塩化メチレン、クロロホルム等のハロゲン化炭化水素類の使用が好ましい。
【００２７】
また、有機溶媒による不純物を抽出して除去する操作は、必要に応じて複数回繰り返すのも好ましい。複数回繰り返す場合には、設定するｐＨ値を微妙に変化させることにより、不純物をより完全に除去することができる。
【００２８】
本発明は、次に、式（１）で表される化合物を含有する水層を分取し、水層のｐＨ値を通常１２〜１４、好ましくは１２．５〜１３．５に調整したのち、式（１）で表される化合物を有機溶媒により抽出する工程を有する。この抽出操作は複数回行なうのが好ましい。
【００２９】
ｐＨ調整は、必要に応じて水等の溶媒を加えた後、酸又はアルカリを添加して行うことができる。また、ｐＨ調整は、式（１）で表される化合物を含有する水溶液に有機溶媒を添加する前に行っても、添加後に行ってもよい。
【００３０】
ｐＨ調整に用いられる酸、アルカリ及び式（１）で表される化合物の抽出溶媒としては、上述の不純物を抽出する場合において例示したものと同様のものを用いることができるが、抽出溶媒は、不純物及び式（１）で表される化合物の再利用の点を考慮して、同一の溶媒を用いるのが好ましい。
また、上記ｐＨ調整工程及び抽出工程は、通常常温で行なうのが好ましいが、分液性を向上させるため、抽出工程は加温しながら行なうこともできる。
【００３１】
最後に、有機層を分取し、所望により乾燥した後、溶媒を濃縮（減圧留去）することにより、目的とする式（１）で表される化合物を得ることができる。このものはさらに蒸留して精製することも可能であるが、この状態でも十分に高純度で、かつ着色が少ないものであり、そのまま次の反応の原料として用いることができる。
【００３２】
【実施例】
以下、本発明を実施例により更に詳細に説明するが、本発明は下記の実施例に限定されるものではない。
（実施例１）
温度計、吹き込み管及び撹拌翼を備えた５リットルのフラスコに、粗２，５−ビス（クロロメチル）−１，４−ジチアン（ＢＣＭＤ）４３４ｇ（純度５９．４％、１．１９モル）、水５５９ｇ及び２８％アンモニア水３３５１ｇ（ＢＣＭＤに対して４６倍モル）を仕込んだ。４０℃まで昇温し、同温度で１時間撹拌した後、４５℃まで昇温し、同温度で１時間さらに撹拌しながら、２８％アンモニア水６５６ｇ（ＢＣＭＤに対して９倍モル）を滴下した。アンモニア水の滴下終了後、４５℃で１時間保持し、室温まで冷却することにより、２，５−ビス（アミノメチル）−１，４−ジチアン（ＢＡＭＤ）を含む水溶液を得た。
【００３３】
上記で得られたＢＡＭＤを含む水溶液に、２８％アンモニア水を加えて、ｐＨ１１．１に調整し、クロロホルム（１回目：５３．６ｍｌ、２回目：２６．８ｍｌ）を加えて、十分に撹拌したのち、静置して、有機層を分離した。さらに、水層をクロロホルム１６０．７ｍｌで２回抽出し、有機層（Ａ）を分離した。得られた水層に２８重量％水酸化ナトリウム水溶液８７１ｇを加えてｐＨ１３．０に調整し、クロロホルム３６０ｇを加えて十分撹拌した後、静置して、有機層を分取した。この操作を４回繰り返し、得られた有機層を合わせて、濃縮することにより、ＢＡＭＤ１３２．６ｇ（収率：６０．３％、純度９７．３％）を得た。
【００３４】
また、有機層（Ａ）に塩酸水を加えて十分に撹拌した後、クロロホルム層を分離し、水層に水酸化ナトリウム水溶液を加えてｐＨ１３としたのち、再びクロロホルムで抽出し、ＢＡＭＤを収率１０．５％で回収することができ、合計で７０．８％の収率であった。
【００３５】
（比較例１）
温度計、吹き込み管及び撹拌機を備えた５Ｌのフラスコに、水７５０ｇと２８％アンモニア水２７５０ｇ（ＢＣＭＤに対し７８倍モル）、粗ＢＣＭＤ（純度６３．８％）を１９６．２ｇ（０．５８モル）仕込んだ。次いで、撹拌下、４０℃まで昇温し、１時間反応させ、５０℃まで昇温しながら２８％アンモニア水７７６ｇ（ＢＣＭＤに対して２２倍モル）を４時間かけて滴下し、３０分熟成させた。反応液から水１１５３ｇを留去し、室温まで冷却後、クロロホルムを加えて（１回目２５０ｍｌ、２回目１００ｍｌ）、有機層を分液除去した。
【００３６】
続いて、２８重量％水酸化ナトリウム水溶液５２０ｇを加えた後、クロロホルム２００ｍｌを加えて有機層を抽出分液し、水層を繰り返し同量のクロロホルムで抽出を行い、最後にクロロホルム１００ｍｌで抽出した。クロロホルム層を集めて濃縮し、純度８４．３％のＢＡＭＤ９１．２ｇを得た（収率７４．４％）。この濃縮液８８．６ｇを８０〜９０Ｐａ、１２８〜１３３℃で減圧蒸留し、本留分６７．８ｇ（純度９８％）を得た（トータル収率６４．３％）。得られたＢＡＭＤの色相は淡黄色であった。また、蒸留残渣は１７．６ｇだった。
【００３７】
【発明の効果】
以上説明したように、本発明は、２，５−ビス（アミノメチル）−１，４−ジチアン等を含有する溶液から抽出操作のみで高純度な２，５−ビス（アミノメチル）−１，４−ジチアン等を単離・精製することができ、高純度な２，５−ビス（アミノメチル）−１，４−ジチアン等の工業的に有利な製造方法であるといえる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a purification method and a production method of a 2,5-bis (aminomethyl) -1,4-dithiane compound useful as a raw material for producing optical products, particularly high refractive index plastic lenses.
[0002]
[Prior art]
Conventionally, as a method for producing 2,5-bis (aminomethyl) -1,4-dithiane (hereinafter referred to as “BAMD”), 2,5-bis (halomethyl) -1,4-dithiane (hereinafter referred to as “BAMD”) BXMD ") is reacted with ammonia in an aqueous solvent, deammonia and dehydrated and concentrated under reduced pressure, adjusted to pH 13 with aqueous sodium hydroxide solution, extracted with chloroform, concentrated and concentrated. Is known to obtain BAMD by distillation under high temperature and high vacuum at 143 to 145 ° C. (Patent Document 1, etc.).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-130264
[Problems to be solved by the invention]
However, in order to perform distillation under a reduced pressure of about 0.4 mmHg as described in the above document on an industrial scale, a special apparatus such as a high vacuum apparatus is required. In addition, since BAMD is generally easily decomposed by heat, when mass-producing BAMD by the above method, the reaction solution is heated for a long time at a high temperature of around 140 ° C. There was a problem of increasing.
[0005]
The present invention has been made in view of such problems, a purification method capable of obtaining a high-purity 2,5-bis (aminomethyl) -1,4-dithiane compound by a simple operation, and a high purity. An object of the present invention is to provide a method for industrially advantageously producing the 2,5-bis (aminomethyl) -1,4-dithiane compound.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present inventors have intensively studied. As a result, they have found that impurities and a target product can be separated by the difference in pH value of an aqueous solution containing BAMD, and have completed the present invention. .
[0007]
That is, the present invention firstly has the formula (1)
[0008]
[Formula 4]

[0009]
(In the formula, R ¹ and R ² each independently represents a hydrogen atom or a C1-C6 alkyl group.) The pH value of the aqueous solution containing the compound and impurities represented by 10.5 to 11.5 Adjusting and removing impurities by extraction with an organic solvent, adjusting the pH value of the aqueous solution obtained to 12.5 to 13.5, and extracting the compound represented by (1) with an organic solvent And a method for purifying the compound represented by the formula (1).
In addition, the present invention secondly, the formula (2)
[0010]
[Chemical formula 5]

[0011]
(In the formula, R ¹ and R ² each independently represent a hydrogen atom or a C1-C6 alkyl group, and X ¹ and X ² each independently represent a halogen atom.)
Ammonia is reacted with the compound represented by the formula (1)
[0012]
[Chemical 6]

[0013]
(Wherein, R ¹ and R ² each independently represents a hydrogen atom or a C1-C6 alkyl group), and a step of obtaining a pH value of an aqueous solution of the mixture. Adjusting to 10.5 to 11.5 , extracting and removing impurities contained in the aqueous solution with an organic solvent, adjusting the pH value of the obtained aqueous solution to 12.5 to 13.5, and Provided is a method for producing a compound represented by formula (1), which comprises a step of extracting a compound represented by formula (1) with an organic solvent.
[0014]
According to the present invention, it is possible to obtain a compound represented by the formula (1) having a purity as high as acceptable as a production raw material for optical products and the like by a simple operation without performing vacuum distillation.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is a method for purifying and producing the compound represented by the formula (1).
In formula (1), R ¹ and R ² are each independently a hydrogen atom; C1-C6 alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl group, etc. Represents a group.
[0016]
Specific examples of the compound represented by the formula (1) include 2,5-bis (aminomethyl) -1,4-dithiane, 2,5-bis (aminomethyl) -2,5-dimethyl-1,4. -Dithian, 2,5-bis (aminomethyl) -2,5-diethyl-1,4-dithiane, 2,5-bis (aminomethyl) -2,5-di-n-propyl-1,4-dithiane 2,5-bis (aminomethyl) -2,5-di-n-butyl-1,4-dithiane and the like.
[0017]
Specific examples of the method for producing the compound represented by the formula (1) include a method of reacting the compound represented by the formula (2) with ammonia.
In formula (2), R ¹ and R ² represent the same meaning as described above, and the same specific examples can be exemplified. X ¹ and X ² each independently represent a halogen atom such as a chlorine atom, a bromine atom, or an iodine atom.
Examples of the method for producing the compound represented by the formula (2) include J. Org. Org. Chem. 34, 3389-3391 (1969), and the like.
[0018]
The solvent used for the reaction of the compound represented by the formula (2) and ammonia is not particularly limited, but a solvent that dissolves ammonia is preferable, and specifically, water; alcohols such as methanol and ethanol; methylene chloride; And halogenated hydrocarbons such as chloroform. These solvents can be used alone or in combination of two or more. Although the usage-amount of a solvent is not restrict | limited in particular, It is 1-100 weight part normally with respect to 1 weight part of compounds represented by Formula (2), Preferably it is the range of 1-20 weight part.
[0019]
Ammonia can be supplied to the reaction system as ammonia water or ammonia gas, or both can be used in combination. The amount of ammonia used is not particularly limited as long as it is excessive with respect to 1 mol of the compound represented by the formula (2), but is usually 1 to 80 times mol, preferably 10 to 60 times mol, more preferably 20 to 60 mol. The range is double moles.
[0020]
Further, the reaction between the compound represented by the formula (1) and ammonia is preferably performed in the presence of a catalyst in order to improve the reaction efficiency. Examples of the catalyst that can be used include cuprous chloride, cupric chloride, zinc chloride, and zinc oxide. Although there is no restriction | limiting in particular in the usage-amount of a catalyst, It is the range of 0.01 molweight%-30 molweight% normally with respect to 1 mol of compounds represented by Formula (2).
[0021]
The reaction normally proceeds smoothly at 30 to 150 ° C, preferably 40 to 120 ° C. When the reaction temperature is set to 30 ° C. or lower, the reaction is slowed. On the other hand, when the reaction temperature exceeds 150 ° C., the reaction pressure is increased, which is not preferable.
[0022]
The present invention is characterized in that the target product is isolated and purified from the reaction mixture obtained as described above only by extraction operation based on the difference in pH value.
In the present invention, the pH value of the aqueous solution containing the compound represented by the formula (1) is usually adjusted to a range of 10 to 12, preferably 10.5 to 11.5, and then impurities are extracted with an organic solvent. And removing it. That is, by setting the aqueous solution containing the compound represented by the formula (1) and the impurity to a predetermined pH value, the difference in the acidity between the impurity and the compound represented by the formula (1) can be utilized. Can be selectively extracted from the aqueous layer to the organic layer and removed.
[0023]
In this step, if necessary, an alcohol solvent such as methanol and ethanol having compatibility with water; an ether solvent such as acetone and tetrahydrofuran, and the like can be used in combination with water. Moreover, it is preferable to remove insoluble impurities in water with a small amount of an organic solvent in advance.
[0024]
The pH value of the aqueous solution can be adjusted to a predetermined value by adding a solvent such as water or methanol as necessary and then adding an acid or an alkali.
Examples of the acid used for pH adjustment include hydrochloric acid, nitric acid, sulfuric acid and the like. Examples of the alkali include potassium hydroxide, sodium hydroxide, potassium carbonate, sodium carbonate, ammonia, aqueous ammonia and the like.
[0025]
Addition of acid or alkali prevents abrupt pH change of the aqueous solution containing the compound represented by the formula (1), and from the viewpoint of precise pH adjustment, add the whole solution little by little with sufficient stirring. It is preferred to do so. Moreover, pH adjustment may be performed before adding an organic solvent to the aqueous solution containing the compound represented by Formula (1), or may be performed after addition.
[0026]
The organic solvent used for extraction of impurities is not particularly limited as long as it is an organic solvent that is not mixed with water. Specific examples include aromatic hydrocarbons such as benzene, toluene and xylene; halogenated hydrocarbons such as methylene chloride, chloroform and carbon tetrachloride; Among these, halogenated hydrocarbons such as methylene chloride and chloroform are preferable from the viewpoint of impurity solubility.
[0027]
In addition, the operation of extracting and removing impurities by the organic solvent is preferably repeated a plurality of times as necessary. In the case of repeating a plurality of times, impurities can be more completely removed by slightly changing the set pH value.
[0028]
In the present invention, the aqueous layer containing the compound represented by the formula (1) is fractionated, and the pH value of the aqueous layer is usually adjusted to 12 to 14, preferably 12.5 to 13.5. And a step of extracting the compound represented by the formula (1) with an organic solvent. This extraction operation is preferably performed a plurality of times.
[0029]
The pH can be adjusted by adding a solvent such as water as necessary and then adding an acid or alkali. Moreover, pH adjustment may be performed before adding an organic solvent to the aqueous solution containing the compound represented by Formula (1), or may be performed after addition.
[0030]
As the extraction solvent for the acid, alkali and compound represented by formula (1) used for pH adjustment, the same solvents as those exemplified in the case of extracting the above-mentioned impurities can be used. In consideration of the reuse of impurities and the compound represented by the formula (1), it is preferable to use the same solvent.
In addition, the pH adjustment step and the extraction step are usually preferably performed at room temperature, but the extraction step can be performed while warming in order to improve the liquid separation property.
[0031]
Finally, the organic layer is collected, dried if desired, and then the solvent is concentrated (distilled under reduced pressure) to obtain the target compound represented by the formula (1). This can be further purified by distillation, but even in this state, it is sufficiently pure and little colored, and can be used as it is as a raw material for the next reaction.
[0032]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to the following Example.
Example 1
In a 5 liter flask equipped with a thermometer, a blowing tube and a stirring blade, 434 g of crude 2,5-bis (chloromethyl) -1,4-dithiane (BCMD) (purity 59.4%, 1.19 mol), 559 g of water and 3351 g of 28% ammonia water (46 times moles relative to BCMD) were charged. The temperature was raised to 40 ° C., and the mixture was stirred at the same temperature for 1 hour, then heated to 45 ° C., and further stirred at the same temperature for 1 hour, and 656 g of 28% aqueous ammonia (9-fold mol to BCMD) was added dropwise. . After completion of the dropwise addition of aqueous ammonia, the solution was kept at 45 ° C. for 1 hour and cooled to room temperature to obtain an aqueous solution containing 2,5-bis (aminomethyl) -1,4-dithiane (BAMD).
[0033]
28% aqueous ammonia was added to the aqueous solution containing BAMD obtained above to adjust to pH 11.1, chloroform (first time: 53.6 ml, second time: 26.8 ml) was added, and the mixture was sufficiently stirred. After that, the organic layer was separated by standing. Further, the aqueous layer was extracted twice with 160.7 ml of chloroform, and the organic layer (A) was separated. To the obtained aqueous layer, 871 g of 28 wt% sodium hydroxide aqueous solution was added to adjust the pH to 13.0, 360 g of chloroform was added and stirred sufficiently, and then allowed to stand to separate the organic layer. This operation was repeated 4 times, and the obtained organic layers were combined and concentrated to obtain 132.6 g of BAMD (yield: 60.3%, purity 97.3%).
[0034]
Further, after adding hydrochloric acid water to the organic layer (A) and stirring sufficiently, the chloroform layer was separated, and the aqueous layer was adjusted to pH 13 by adding aqueous sodium hydroxide solution, and then extracted again with chloroform to obtain BAMD yield. It could be recovered at 10.5%, for a total yield of 70.8%.
[0035]
(Comparative Example 1)
In a 5 L flask equipped with a thermometer, a blowing tube and a stirrer, 196.2 g (0.58) of 750 g of water, 2750 g of 28% aqueous ammonia (78 times mol to BCMD), and crude BCMD (purity 63.8%). Mol) charged. Next, with stirring, the temperature was raised to 40 ° C. and reacted for 1 hour. While raising the temperature to 50 ° C., 776 g of 28% aqueous ammonia (22-fold mol to BCMD) was added dropwise over 4 hours and aged for 30 minutes. It was. After removing 1153 g of water from the reaction solution and cooling to room temperature, chloroform was added (first 250 ml, second 100 ml), and the organic layer was separated and removed.
[0036]
Subsequently, 520 g of 28 wt% sodium hydroxide aqueous solution was added, 200 ml of chloroform was added, the organic layer was extracted and separated, the aqueous layer was repeatedly extracted with the same amount of chloroform, and finally extracted with 100 ml of chloroform. The chloroform layer was collected and concentrated to obtain 91.2 g of BAMD having a purity of 84.3% (yield 74.4%). 88.6 g of this concentrated liquid was distilled under reduced pressure at 80 to 90 Pa and 128 to 133 ° C. to obtain 67.8 g (purity 98%) of the main fraction (total yield 64.3%). The hue of the obtained BAMD was pale yellow. Moreover, the distillation residue was 17.6g.
[0037]
【The invention's effect】
As described above, the present invention provides a high-purity 2,5-bis (aminomethyl) -1, which is extracted from a solution containing 2,5-bis (aminomethyl) -1,4-dithiane and the like only by an extraction operation. It can be said that this is an industrially advantageous production method of high-purity 2,5-bis (aminomethyl) -1,4-dithiane and the like because 4-dithiane can be isolated and purified.

Claims (2)

Formula (1)

(In the formula, R ¹ and R ² each independently represents a hydrogen atom or a C1-C6 alkyl group.) The pH value of the aqueous solution containing the compound and impurities represented by 10.5 to 11.5 is adjusted. And removing the impurities by extraction with an organic solvent;
The pH value of the obtained aqueous solution is adjusted to 12.5 to 13.5 , and the compound represented by the formula (1) is extracted with an organic solvent. Purification method. Formula (2)

(In the formula, R ¹ and R ² each independently represent a hydrogen atom or a C1-C6 alkyl group, and X ¹ and X ² each independently represent a halogen atom.)
A compound represented by the formula (1) is reacted with ammonia.

(Wherein R ¹ and R ² each independently represents a hydrogen atom or a C1-C6 alkyl group), and a step of obtaining a reaction mixture containing the compound represented by:
Adjusting the pH value of the aqueous solution of the mixture to 10.5 to 11.5 and extracting and removing impurities contained in the aqueous solution with an organic solvent;
The pH value of the obtained aqueous solution is adjusted to 12.5 to 13.5 , and the compound represented by the formula (1) is extracted with an organic solvent. Production method.