JPH06199747A - Production of l-alaninol - Google Patents
Production of l-alaninolInfo
- Publication number
- JPH06199747A JPH06199747A JP36075492A JP36075492A JPH06199747A JP H06199747 A JPH06199747 A JP H06199747A JP 36075492 A JP36075492 A JP 36075492A JP 36075492 A JP36075492 A JP 36075492A JP H06199747 A JPH06199747 A JP H06199747A
- Authority
- JP
- Japan
- Prior art keywords
- alanine
- alaninol
- ester
- nabh
- inorganic acid
- 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
Links
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明はＬ−アラニノールの製造
方法に関する。FIELD OF THE INVENTION The present invention relates to a method for producing L-alaninol.
【０００２】[0002]
【従来の技術・発明が解決しようとする課題】Ｌ−アラ
ニノールは医薬品中間体等として使用されているが、従
来よりＬ−アラニンエステルの還元により製造されてい
る。例えば、Ｌ−アラニノールはＬ−アラニンエステル
をＣｕＯ・ＣｕＣｒ2 Ｏ4 触媒を使用し１５０℃、１４
０気圧という高温・高圧下で還元する方法（Ｊ．Ａｍ．
Ｃｈｅｍ，Ｓｏｃ ８１巻，１０９６頁 １９５２年）
があるが、工業的に実施可能な方法とはいえない。2. Description of the Related Art L-Alaninol has been used as an intermediate for pharmaceuticals and the like, but it has been conventionally produced by reduction of L-alanine ester. For example, L-alaninol is prepared by converting L-alanine ester into a CuO.CuCr 2 O 4 catalyst at 150 ° C., 14
Method of reduction under high temperature and high pressure of 0 atm (J. Am.
Chem, Soc 81, 1096, 1952).
However, it is not an industrially feasible method.
【０００３】又、Ｌ−アラニンを直接ＬｉＡｌＨ4 で還
元する方法（Ｍｏｎａｆｃｉｅｆｔｅ ｆｕｒ Ｃｈｅ
ｍｉｅ ８３巻，５４１頁，１９５２年）もあるが、Ｌ
ｉＡｌＨ4 の取扱いと安全対策及び生成物水解後の水溶
液からの単離は容易でない。Further, a method of directly reducing L-alanine with LiAlH 4 (Monafciefte fur Che)
Mie 83, 541, 1952), but L
Handling and safety measures of iAlH 4 and isolation from aqueous solution after product hydrolyzation are not easy.
【０００４】さらに、ＤＬ−アラニンエチルエステルを
ＮａＢＨ4 で還元した後、生ずるＤＬ−アラニノールを
塩酸塩として取り出し、ナトリウムメチラートで遊離の
ＤＬ−アラニノールとし、ついで蒸留して精製ＤＬ−ア
ラニノールを得る方法がある（Ｃｚｅｃｈ．ＣＳ、２０
９１５１、１９８３年）。しかし、本発明者等は該チェ
コスロバキア国特許の方法に準じ、Ｌ−アラニンエチル
エステルをＮａＢＨ4で還元する方法を検討したが、収
率は３０％以下と低いうえ、収率変動が甚だしく、再現
性に乏しかった。このように従来法ではＬ−アラニノー
ルを高収率で工業的有利に製造する方法ではないのが実
情である。Furthermore, after reducing DL-alanine ethyl ester with NaBH 4 , the resulting DL-alaninol is taken out as a hydrochloride, converted into free DL-alaninol with sodium methylate, and then distilled to obtain purified DL-alaninol. There is (Czech.CS, 20
9151, 1983). However, the present inventors have examined a method of reducing L-alanine ethyl ester with NaBH 4 in accordance with the method of the Czechoslovakian patent, but the yield is as low as 30% or less, and the yield variation is extremely large. The reproducibility was poor. As described above, the conventional method is not a method for producing L-alaninol in a high yield industrially advantageously.
【０００５】[0005]
【課題を解決するための手段】本発明者らはＬ−アラニ
ンエステルの塩酸塩を用いて、これの還元条件を詳細に
検討した結果、Ｌ−アラニンエステルの無機酸塩を直接
ＮａＢＨ4 で還元することにより簡易かつ高収率で再現
性よくＬ−アラニノールを製造できる事を見出し、本発
明を完成するに到った。Means for Solving the Problems As a result of detailed investigation of the reducing conditions of L-alanine ester hydrochloride using the hydrochloride of L-alanine ester, the present inventors directly reduced the inorganic acid salt of L-alanine ester with NaBH 4 . By doing so, it was found that L-alaninol can be easily produced with high yield and reproducibility, and the present invention has been completed.
【０００６】即ち、本発明の要旨はＬ−アラニンエステ
ルの無機酸塩を大過剰のＮａＢＨ4水溶液中に滴下して
還元することによりＬ−アラニノールを製造する方法に
関する。That is, the gist of the present invention relates to a method for producing L-alaninol by dropping an inorganic acid salt of L-alanine ester into a large excess of NaBH 4 aqueous solution and reducing it.
【０００７】本発明においては、Ｌ−アラニンエステル
の無機酸塩を塩のまま直接還元することが極めて重要で
ある。従来の技術の如くアラニンエステルの塩酸塩をア
ルカリで中和することは収率の低下を招くからである。
即ち、本発明者等は、従来の技術によるＬ−アラニノー
ルの合成法を追試してみたが、再現性がなく、Ｌ−アラ
ニンからの収率も３０％と低収率であった。低収率とな
る原因を究明するため、種々条件を検討した結果、Ｌ−
アラニンエステル塩酸塩をアルカリ例えば苛性ソーダ水
溶液、Ｎａ−メチラート等の等量添加により中和した場
合、エステルの大半が加水分解を受け還元不能となるた
めの収率低下である事を見出した。また、このＬ−アラ
ニンエステル塩酸塩の中和時、時間の経過につれてエス
テルの加水分解が進行するため再現性が乏しいことも明
らかにすることができた。従って、本発明では、Ｌ−ア
ラニンエステルの加水分解を防止する目的で、Ｌ−アラ
ニンエステルの無機酸塩を中和せず、無機酸の塩のまま
直接ＮａＢＨ4 と反応させて還元する方法が採られる。In the present invention, it is extremely important to directly reduce the inorganic acid salt of L-alanine ester as a salt. This is because neutralizing the hydrochloride of alanine ester with an alkali as in the conventional technique causes a decrease in yield.
That is, the inventors of the present invention additionally tried a conventional method for synthesizing L-alaninol, but it was not reproducible and the yield from L-alanine was as low as 30%. As a result of examining various conditions in order to investigate the cause of the low yield, L-
It has been found that when alanine ester hydrochloride is neutralized by adding an equal amount of an alkali such as an aqueous solution of caustic soda and Na-methylate, most of the ester is hydrolyzed and cannot be reduced, resulting in a decrease in yield. It was also revealed that the reproducibility was poor because the hydrolysis of the ester proceeded with the passage of time during the neutralization of this L-alanine ester hydrochloride. Therefore, in the present invention, for the purpose of preventing hydrolysis of L-alanine ester, a method of directly reacting with NaBH 4 as a salt of an inorganic acid without reducing the inorganic acid salt of L-alanine ester and reducing To be taken.
【０００８】本発明の方法に用いられる原料化合物とし
ては、Ｌ−アラニンエステルの塩であればいずれも利用
できる。例えば、エステルとしてはＬ−アラニンの低級
アルキルエステルが利用でき、Ｌ−アラニンメチルエス
テル、Ｌ−アラニンエチルエステル、Ｌ−アラニンプロ
ピルエステル等が特に好ましい。またかかるＬ−アラニ
ンエステルの塩としては無機酸の塩であればいずれでも
よく、塩酸塩、硫酸塩、ｐ−トルエンスルホン酸塩等が
特に有利に利用できる。As the raw material compound used in the method of the present invention, any salt of L-alanine ester can be used. For example, a lower alkyl ester of L-alanine can be used as the ester, and L-alanine methyl ester, L-alanine ethyl ester, L-alanine propyl ester and the like are particularly preferable. The salt of the L-alanine ester may be any salt of an inorganic acid, and hydrochloride, sulfate, p-toluenesulfonate and the like can be particularly advantageously used.
【０００９】本発明においては、Ｌ−アラニンエステル
の無機酸塩を有機溶媒に溶解し、これとＮａＢＨ4 とを
反応させる。この反応に使用される有機溶媒としては、
水とよく混和し、ＮａＢＨ4 と反応しないものであれば
よく、好ましくはメタノール、エタノール、イソプロパ
ノール等の低級アルコール類が用いられ、反応によって
副生する無機物を濾別するときの流動性からみるとエタ
ノールの使用が最も好ましい。In the present invention, the inorganic acid salt of L-alanine ester is dissolved in an organic solvent and this is reacted with NaBH 4 . The organic solvent used in this reaction,
Any material that is well miscible with water and does not react with NaBH 4 may be used. Preferably, lower alcohols such as methanol, ethanol and isopropanol are used. From the viewpoint of fluidity when the inorganic substances by-produced by the reaction are filtered out, Most preferred is the use of ethanol.
【００１０】本発明に用いられるＮａＢＨ4 は、冷水中
に溶解して反応に供され、その使用量は原料化合物であ
るＬ−アラニンエステルの無機酸塩に対して大過剰であ
り、通常３．０〜５．０倍当量が好ましい。３．０倍当
量より少ないとエステルの加水分解によるＬ−アラニン
の副生により収率が低下し、５．０倍当量を越えてもそ
れに見合う効果はなく、高価なＮａＢＨ4 の消費が増加
し不経済である。NaBH 4 used in the present invention is dissolved in cold water to be used in the reaction, and its amount used is in a large excess with respect to the inorganic acid salt of L-alanine ester which is a raw material compound, and usually 3. 0 to 5.0 times equivalent is preferable. If the amount is less than 3.0 times equivalent, the yield is decreased due to L-alanine by-product due to hydrolysis of ester, and if it exceeds 5.0 times equivalent, there is no corresponding effect, and consumption of expensive NaBH 4 increases. It is uneconomical.
【００１１】Ｌ−アラニンエステルの無機酸塩とＮａＢ
Ｈ4 との反応は、ＮａＢＨ4 の冷水溶液中にＬ−アラニ
ンエステルの無機酸塩のアルコール溶液を長時間かけて
滴下することにより行う。この条件下では、常にＬ−ア
ラニンエステルの無機酸塩が大過剰のＮａＢＨ4 中に滴
下されることになり、該エステルの加水分解が最少限に
押さえられるという効果が得られ、収率、再現性の向上
に資するからである。Inorganic acid salt of L-alanine ester and NaB
The reaction with H 4 is performed by dropping an alcohol solution of an inorganic acid salt of L-alanine ester into a cold aqueous solution of NaBH 4 over a long period of time. Under this condition, the inorganic acid salt of the L-alanine ester is always added dropwise to a large excess of NaBH 4 , and the effect of suppressing the hydrolysis of the ester to the minimum can be obtained. This is because it contributes to the improvement of sex.
【００１２】本発明における反応の温度としては１０〜
４０℃、好ましくは１５〜２５℃が選ばれる。反応温度
を上げれば反応速度は高まる。しかし、反応を短時間で
完了させるため、反応温度を４０℃以上とすると、原料
化合物であるＬ−アラニンエステルの無機酸塩の中和・
加水分解が起こり、反応収率を低下させるので好ましく
ない。反応時間は通常１０〜１５時間で終了する。Ｌ−
アラニノールの反応液からの抽出・精製は、過剰のＮａ
ＢＨ4 の分解、無機物濾別、抽出等の常法により行われ
る。The reaction temperature in the present invention is 10 to
40 ° C, preferably 15 to 25 ° C is selected. Increasing the reaction temperature increases the reaction rate. However, in order to complete the reaction in a short time, if the reaction temperature is set to 40 ° C. or higher, the inorganic acid salt of the starting compound L-alanine ester is neutralized.
Hydrolysis occurs and the reaction yield is reduced, which is not preferable. The reaction time is usually 10 to 15 hours. L-
Extraction and purification of alaninol from the reaction solution is performed using excess Na
It is carried out by a conventional method such as decomposition of BH 4 , filtration of inorganic substances, extraction and the like.
【００１３】[0013]
【実施例】以下、実施例及び参考例により本発明をさら
に詳しく説明するが、本発明はこれらの実施例等により
なんら限定されるものではない。 実施例１ 冷水５６０ｍｌ中にＮａＢＨ4 ３．０モルを添加、溶解
した溶液中に、Ｌ−アラニンエチルエステル塩酸塩１．
０モルをエタノール５６０ｍｌに溶解した溶液を１５〜
２０℃で５時間を要して滴下し、更に２０〜２８℃で熟
成して反応を完了した。反応後、過剰のＮａＢＨ4 をア
セトンで分解し、酢酸エチル１０００ｍｌを流入し析出
する無機物を濾別した。濾液中の下層水層部は酢酸エチ
ル６００ｍｌで抽出し、酢酸エチル層を減圧下で溶媒を
留去したのち真空蒸留した。精製アラニノールは、Ｈ−
ＮＭＲスペクトル（ＣＤＣｌ3 溶媒、ＴＭＳ内部標準）
で同定した。主なピークは１．０４ｐｐｍ（３Ｈ、ｄ、
ＣＨ3 ）、２．４１ｐｐｍ（３Ｈ、ｓ、ＮＨ2 、Ｏ
Ｈ）、２．８７〜３．５３ｐｐｍ（３Ｈ、ｍ、ＣＨ2 −
Ｏ、ＣＨ−Ｎ）である。Ｌ−アラニノールの収率はＬ−
アラニンに対し６７．０％であった。EXAMPLES The present invention will be described in more detail with reference to Examples and Reference Examples, but the present invention is not limited to these Examples. Example 1 3.0 mol of NaBH 4 was added and dissolved in 560 ml of cold water, and L-alanine ethyl ester hydrochloride 1.
A solution of 0 mol dissolved in 560 ml of ethanol was added to
The mixture was added dropwise at 20 ° C. over 5 hours, and further aged at 20 to 28 ° C. to complete the reaction. After the reaction, excess NaBH 4 was decomposed with acetone, 1000 ml of ethyl acetate was introduced, and the precipitated inorganic substance was separated by filtration. The lower aqueous layer portion of the filtrate was extracted with 600 ml of ethyl acetate, the ethyl acetate layer was distilled under reduced pressure to remove the solvent, and then vacuum distilled. Purified alaninol is H-
NMR spectrum (CDCl 3 solvent, TMS internal standard)
It was identified by. The main peak is 1.04 ppm (3H, d,
CH 3 ), 2.41 ppm (3H, s, NH 2 , O
H), 2.87~3.53ppm (3H, m , CH 2 -
O, CH-N). The yield of L-alaninol is L-
It was 67.0% with respect to alanine.
【００１４】実施例２ 冷水５６０ｍｌ中にＮａＢＨ4 ３．０モルを添加、溶解
した溶液中に、Ｌ−アラニンエチルエステル塩酸塩１．
０モルをメタノール５６０ｍｌに溶解した溶液を１５〜
２０℃で５時間を要して滴下し、更に２０〜２８℃で熟
成して反応を完了した。反応液は実施例１と同様に処理
した。Ｌ−アラニノールの収率はＬ−アラニンに対して
５０．０％であった。Example 2 3.0 mol of NaBH 4 was added to and dissolved in 560 ml of cold water, and L-alanine ethyl ester hydrochloride 1.
A solution of 0 mol dissolved in 560 ml of methanol
The mixture was added dropwise at 20 ° C. over 5 hours, and further aged at 20 to 28 ° C. to complete the reaction. The reaction solution was treated in the same manner as in Example 1. The yield of L-alaninol was 50.0% based on L-alanine.
【００１５】実施例３ 冷水５６０ｍｌ中にＮａＢＨ4 ３．０モルを添加、溶解
した溶液中に、Ｌ−アラニンエチルエステル塩酸塩１．
０モルをイソプロパノール５６０ｍｌに溶解した溶液を
１５〜２０℃で５時間を要して滴下し、更に２０〜２８
℃で熟成して反応を完了した。反応液は実施例１と同様
に処理した。Ｌ−アラニノールの収率はＬ−アラニンに
対して５６．０％であった。Example 3 3.0 mol of NaBH 4 was added and dissolved in 560 ml of cold water, and L-alanine ethyl ester hydrochloride 1.
A solution of 0 mol dissolved in 560 ml of isopropanol was added dropwise at 15 to 20 ° C over 5 hours, and further 20 to 28
The reaction was completed by aging at ° C. The reaction solution was treated in the same manner as in Example 1. The yield of L-alaninol was 56.0% with respect to L-alanine.
【００１６】実施例４ 冷水５６０ｍｌ中にＮａＢＨ4 ４．０モルを添加、溶解
した溶液中に、Ｌ−アラニンエチルエステル塩酸塩１．
０モルをエタノール５６０ｍｌに溶解した溶液を実施例
１と同様に処理した。Ｌ−アラニノールの収率はＬ−ア
ラニンに対して６８．０％であった。Example 4 4.0 mol of NaBH 4 was added and dissolved in 560 ml of cold water, and L-alanine ethyl ester hydrochloride 1.
A solution of 0 mol dissolved in 560 ml of ethanol was treated in the same manner as in Example 1. The yield of L-alaninol was 68.0% with respect to L-alanine.
【００１７】実施例５ 冷水５６０ｍｌ中にＮａＢＨ4 ３．０モルを添加、溶解
した溶液中に、Ｌ−アラニンメチルエステル塩酸塩１．
０モルをエタノール５６０ｍｌに溶解した溶液を１５〜
２０℃で５時間を要して滴下し、更に２０〜２８℃で熟
成して反応を完了した。反応液は実施例１と同様に処理
した。Ｌ−アラニノールの収率はＬ−アラニンに対して
６６．５％ であった。Example 5 3.0 mol of NaBH 4 was added to and dissolved in 560 ml of cold water, and L-alanine methyl ester hydrochloride 1.
A solution of 0 mol dissolved in 560 ml of ethanol was added to
The mixture was added dropwise at 20 ° C. over 5 hours, and further aged at 20 to 28 ° C. to complete the reaction. The reaction solution was treated in the same manner as in Example 1. The yield of L-alaninol was 66.5% based on L-alanine.
【００１８】参考例 Ｌ−アラニンエチルエステル塩酸塩１モルを水４００ｍ
ｌに溶解し氷冷却下１０℃以下で苛性ソーダ１モルを１
６０ｍｌの水に溶解した溶液を滴下・中和したのちエタ
ノール５６０ｍｌを流入し、ＮａＢＨ4 ３．０モルを５
時間を要して１５〜２０℃で分割投入し、２０〜２８℃
で熟成して反応を完了した。反応液は実施例１と同様に
処理した。Ｌ−アラニノールの収率はＬ−アラニンに対
して３０．５％であった。Reference Example 1 mol of L-alanine ethyl ester hydrochloride was added to 400 m of water.
1 mol of caustic soda was dissolved in 1 liter under ice cooling at 10 ° C or lower.
After dripping and neutralizing the solution dissolved in 60 ml of water, 560 ml of ethanol was introduced, and 3.0 mol of NaBH 4 was added to 5 ml.
It takes 20 to 28 ℃ at 15 to 20 ℃ in divided doses.
The reaction was completed by aging. The reaction solution was treated in the same manner as in Example 1. The yield of L-alaninol was 30.5% based on L-alanine.
【００１９】[0019]
【発明の効果】Ｌ−アラニンエステルの無機酸塩を直接
ＮａＢＨ4 で還元する本発明の方法により、簡易かつ高
収率で収率変動もなくＬ−アラニノールを工業的有利に
製造できる。INDUSTRIAL APPLICABILITY By the method of the present invention in which the inorganic acid salt of L-alanine ester is directly reduced with NaBH 4 , L-alaninol can be produced industrially advantageously in a simple and high yield with no fluctuation in yield.
Claims (1)
剰のＮａＢＨ4 水溶液中に滴下して還元することを特徴
とするＬ−アラニノールの製造方法。1. A method for producing L-alaninol, which comprises adding an inorganic acid salt of L-alanine ester dropwise to a large excess of NaBH 4 aqueous solution for reduction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP36075492A JPH06199747A (en) | 1992-12-28 | 1992-12-28 | Production of l-alaninol |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP36075492A JPH06199747A (en) | 1992-12-28 | 1992-12-28 | Production of l-alaninol |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH06199747A true JPH06199747A (en) | 1994-07-19 |
Family
ID=18470781
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP36075492A Pending JPH06199747A (en) | 1992-12-28 | 1992-12-28 | Production of l-alaninol |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH06199747A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999007199A2 (en) * | 1997-08-08 | 1999-02-18 | Lonza Ag | Method for producing l-alaninol and gamma-glutamyl isopropylamide and a microbial strain of the pseudomonas |
| WO2005061435A1 (en) * | 2003-12-22 | 2005-07-07 | Sumitomo Chemical Company, Limited | Method for producing optically active bisamido alcohol compound |
| JP2005206580A (en) * | 2003-12-22 | 2005-08-04 | Sumitomo Chemical Co Ltd | Method for producing optically active bisamidealcohol compound |
| US7659409B2 (en) | 2002-03-19 | 2010-02-09 | Mitsubishi Chemical Corporation | 3-Hydroxy-3-(2-thienyl) propionamides and production method thereof, and production method of 3-amino-1-(2-thienyl)-1-propanols using the same |
| US8344182B2 (en) | 2007-12-20 | 2013-01-01 | Basf Se | Process for the preparation of (S)-2-amino-1-propanol (L-alaninol) from (S)-1-methoxy-2-propylamine |
-
1992
- 1992-12-28 JP JP36075492A patent/JPH06199747A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999007199A2 (en) * | 1997-08-08 | 1999-02-18 | Lonza Ag | Method for producing l-alaninol and gamma-glutamyl isopropylamide and a microbial strain of the pseudomonas |
| WO1999007199A3 (en) * | 1997-08-08 | 1999-04-29 | Lonza Ag | Method for producing l-alaninol and gamma-glutamyl isopropylamide and a microbial strain of the pseudomonas |
| US7659409B2 (en) | 2002-03-19 | 2010-02-09 | Mitsubishi Chemical Corporation | 3-Hydroxy-3-(2-thienyl) propionamides and production method thereof, and production method of 3-amino-1-(2-thienyl)-1-propanols using the same |
| WO2005061435A1 (en) * | 2003-12-22 | 2005-07-07 | Sumitomo Chemical Company, Limited | Method for producing optically active bisamido alcohol compound |
| JP2005206580A (en) * | 2003-12-22 | 2005-08-04 | Sumitomo Chemical Co Ltd | Method for producing optically active bisamidealcohol compound |
| US7612236B2 (en) | 2003-12-22 | 2009-11-03 | Sumitomo Chemical Company, Limited | Method for producing optically active bisamidoalcohol compound |
| JP4706241B2 (en) * | 2003-12-22 | 2011-06-22 | 住友化学株式会社 | Process for producing optically active bisamide alcohol compound |
| US8344182B2 (en) | 2007-12-20 | 2013-01-01 | Basf Se | Process for the preparation of (S)-2-amino-1-propanol (L-alaninol) from (S)-1-methoxy-2-propylamine |
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