JP4258609B2 - Method for producing alicyclic tetracarboxylic acid - Google Patents

Description

【０００９】
で表されるヒドロキシ−ジシクロペンタジエンを溶媒存在下、無触媒で硝酸酸化することを特徴とする式［２］
【００１０】
【化４】

【００１１】
で表される１，２，４−トリカルボキシ−３−カルボキシメチルシクロペンタンの製造法。
（２）前記式［１］で表されるヒドロキシ−ジシクロペンタジエンと溶媒の混合液に、硝酸を分割滴下する前記（１）に記載の１，２，４−トリカルボキシ−３−カルボキシメチルシクロペンタンの製造法。
（３）溶媒が脂肪族ハロゲン化炭化水素化合物、脂肪族ニトロ化合物、脂肪族カルボン酸化合物及び脂肪族スルホン化合物の中から選ばれる少なくとも１種の溶媒である前記（１）又は（２）に記載の１，２，４−トリカルボキシ−３−カルボキシメチルシクロペンタンの製造法。
（４）溶媒が１，２−ジクロロエタン、ニトロメタン、酢酸及びスルホランの中から選ばれる少なくとも１種の溶媒である前記（１）乃至（３）のいずれか１つに記載の１，２，４−トリカルボキシ−３−カルボキシメチルシクロペンタンの製造法。
（５）反応温度が４５〜７０℃である前記（１）乃至（４）のいずれか１つに記載の１，２，４−トリカルボキシ−３−カルボキシメチルシクロペンタンの製造法。
（６）前記（１）乃至（５）のいずれか１つに記載の１，２，４−トリカルボキシ−３−カルボキシメチルシクロペンタンの製造法において、得られた１，２，４−トリカルボキシ−３−カルボキシメチルシクロペンタンの再結晶溶媒として、１，４−ジオキサンとアセトニトリル又は１，４−ジオキサンとアセトニトリル及び酢酸エチルの混合溶媒を用いることを特徴とする１，２，４−トリカルボキシ−３−カルボキシメチルシクロペンタンの製造法。
【００１２】
以下本発明を詳細に説明する。
【００１３】
【発明の実施の形態】
本発明のＴＣＭＰの製造法は、下記のルートで表される。
【００１４】
【化５】

【００１５】
原料のＨＤＣＰは、ＤＣＰＤを硝酸や硫酸の水溶液中で加温することにより容易に製造できる。又、市販品をそのまま使用することもできる。
【００１６】
本発明の第一は、溶媒の使用である。ＨＤＣＰと硝酸の反応は、無溶媒下では極めて激しい発熱を伴い、反応温度の制御がむずかしい。この急激な昇温による脱炭酸したＴＣＰの副生が増加する。又、発生した炭酸ガスや硝酸の分解ＮＯ_２ガスの飛散に伴う硝酸のロスが大きく、大過剰の硝酸が必要になる。
【００１７】
そこで、溶媒を存在させることにより、急激な昇温が緩和される。また、溶媒中への硝酸の保持作用による飛散に伴う硝酸のロスが減少する。溶媒の種類としては、例えば、硝酸中で安定な化合物が好ましく、具体的には脂肪族ハロゲン化炭化水素化合物、脂肪族ニトロ化合物、脂肪族カルボン酸化合物及び脂肪族スルホン化合物等が挙げられる。更に具体的には、脂肪族ハロゲン化炭化水素化合物としては、１，２−ジクロロエタン、１，１，１−トリクロロエタン及び１，２，３−トリクロロプロパン、脂肪族ニトロ化合物としては、ニトロメタン、ニトロエタン及びニトロプロパン、脂肪族カルボン酸化合物としては、蟻酸、酢酸及びプロピオン酸、脂肪族スルホン化合物としては、ジメチルスルホキシド及びスルホラン等が一例として挙げられる。特には、１，２−ジクロロエタン、ニトロメタン、酢酸及びスルホランが好ましい。これらの溶媒の中から選ばれた少なくとも１種類の溶媒を用いることができる。
【００１８】
溶媒量は、多くなると硝酸の滴下に伴う発熱が温和になるが、反応進行が遅くなる傾向にある。従って、原料ＨＤＣＰに対して１〜１０モル質量倍が好ましく、特には１〜５質量倍が好ましい。この溶媒の存在によって、工業的な安定操業が可能となり、且つ目的物ＴＣＭＰ収率が向上する。
【００１９】
本発明の二つ目は、無触媒下でも反応が可能であることを見出した。従来のメタバナジン酸アンモニウム等を使用する場合は、反応後高濃度の硝酸溶液中から晶析させた生成物ＴＣＭＰ結晶は、有機溶媒による洗浄でもバナジウム金属の混入が見られ、電子材料等モノマー分野で問題視されていた。そこで、所定の反応温度、硝酸量及び溶媒量等の設定により、本反応は、無触媒下でも従来の触媒存在時とほぼ同程度の速度で進行することをガスクロマトグラフィー（ＧＣ）による反応液の追跡から確認した。このことにより目的生成物中への重金属の混入が回避された。よって、微量の金属の混入が問題視される精密工業分野への用途が可能になった。
【００２０】
本反応では、炭素−炭素結合を開裂してジカルボン酸にする酸化剤として安価な硝酸を用いるのが好ましい。その濃度は、低濃度の場合は中間体類の副生が多くなりテトラカルボン酸類の選択性が低くなるので６０〜９０％の高濃度が好ましい。仕込み量は、少ない場合は、原料や中間体類が残余し、温度を上げると副生物のＴＣＰが増加するので好ましくない。一方、多い方が反応が速くなるが反応後の残余硝酸の除去が煩雑になる。従って、ＨＤＣＰに対して８〜２０モル当量が好ましく、更には１０〜１２モル当量が経済的で好ましい。
【００２１】
本発明の三つ目は、仕込み順序である。即ち、原料のＨＤＣＰと有機溶媒を反応槽に仕込んだ後、攪拌しながら所望の温度で硝酸水溶液を滴下する方法である（順滴下法）。滴下は、硝酸水溶液の滴下と同時に反応を進行させながら、その発熱による昇温を制御しつつ行う必要があり、一般に反応規模が大きくなるほど滴下時間も長くなる傾向にある。通常は、２〜１０時間かけて行うことが好ましい。
【００２２】
本発明で重要なのが反応温度の設定である。高温ほど反応が速いが脱炭酸したＴＣＰの副生を伴うので、通常４５〜７０℃の範囲が好ましく、特には５０〜６５℃の範囲が好ましい。
【００２３】
反応時間は、ガスクロマトグラフィー（ＧＣ）や液体クロマトグラフィー（ＬＣ）で反応追跡して決定することができるが、通常４〜３０時間で終了させることができる。本反応は、常圧又は加圧で行うこともでき、又回分式又は連続式でも可能である。
【００２４】
反応生成物の単離は、反応終了後反応液の生成物濃度を約４５質量％付近まで濃縮してから１５〜３０℃で１５時間以上、通常１５時間〜３０時間静置又は攪拌せることにより、結晶が析出するのでこれを濾過により分離した後、水及びトルエンで洗浄・乾燥させることによりＴＣＭＰの白色結晶が得られる。また、生成物の結晶を加えてから晶析操作を行うことにより結晶の析出を促進させることもできる。
【００２５】
更に、高純度品を得る場合は、ＴＣＭＰ粗結晶を１，４−ジオキサンに加温溶解後、濃縮しながらアセトニトリル又はアセトニトリルと酢酸エチルの混合液を加えて室温付近に冷却することにより再結晶させて精製させることができる。
【００２６】
【実施例】
以下に実施例を挙げ、本発明を更に具体的に説明するが、本発明はこれらに限定されるものではない。尚、実施例で用いた分析法は以下の通りである。
[１] ガスクロマトグラフィー(GC)
機種 : 島津製作所社製 商品名 GC-17A：カラム:キャピラリカラムCBP1-W25-100(25m X 0.53mmφ X 1μm)、カラム温度: 100℃(保持 2min.)〜290℃(保持10min.)、8℃/min.(昇温速度)、注入口温度:290℃、検出器温度:290℃、キャリアガス：ヘリウム、検出法:FID法.
[２] バナジウム定量分析
サンプルを硫酸、硝酸で加熱分解後、ICP-AES測定した。
ICP-AES：セイコーインスツルメンツ社製 商品名 VISTA PRO：波長：213.618nm、検量線：絶対検量線法
【００２７】
実施例１
３００ｍｌ耐熱ガラス製４つ口反応フラスコにＨＤＣＰ１５．０ｇ（０．１０ｍｏｌ）、１，２−ジクロロエタン（ＥＤＣ）４５．０ｇ（３重量倍）を仕込んだ。続いて攪拌しながら５０℃に昇温してから、７３％硝酸９５ｇ（１．１０ｍｏｌ）を滴下開始した。滴下に伴い内温は最高５５℃まで昇温し、５０〜５５℃間で２時間かけて滴下した。その後徐々に６０℃に昇温させて２２時間攪拌を継続した。反応液の一部を採り、ガスクロマトグラフィー（ＧＣ）で分析の結果、未反応ＨＤＣＰは消失し、ＴＣＭＰ７７．２面積％、ＴＣＰ１４．９面積％であった。 そこで反応を停止させ、反応液を反応生成物濃度が約４５％付近になるまでそのまま濃縮し、更に室温（２５℃）で２４時間攪拌すると結晶が析出した。この結晶を濾過し、更に水洗及びトルエン洗浄した後乾燥すると白色結晶が１６．８ｇ（ＴＣＭＰ９０．２面積％、ＴＣＰ９．８面積％）（ＴＣＭＰ収率５８．３％）得られた。
【００２８】
この結晶に１，４−ジオキサン８４ｇを加えて７０℃に加温溶解後、濃縮してから得られた油状物にアセトニトリル３０ｇを加えて加温再溶解した後、氷冷下で１時間攪拌してから室温（２５℃）で２０時間攪拌しながら再晶析させた。得られた結晶を濾過し、アセトニトリル洗浄した後乾燥することにより、白色結晶１３．０ｇ（ＴＣＭＰ１００面積％）（ＴＣＭＰ収率５０．１％）
【００２９】
実施例２
１０００ｍｌ耐熱ガラス製４つ口反応フラスコにＨＤＣＰ４５．０ｇ（０．３０ｍｏｌ）、１，２−ジクロロエタン（ＥＤＣ）４５．０ｇ（１重量倍）を仕込んだ。続いて攪拌しながら５０℃に昇温してから、７０％硝酸２９７ｇ（３．３０ｍｏｌ）を滴下開始した。滴下に伴い内温は最高５５℃まで昇温し、５０〜５５℃間で４時間かけて滴下した。その後徐々に６０℃に昇温させて２４時間攪拌を継続した。反応液の一部を採り、ガスクロマトグラフィー（ＧＣ）で分析の結果、未反応ＨＤＣＰは消失し、ＴＣＭＰ７２．１面積％、ＴＣＰ１７．８面積％であった。そこで反応を停止させ、反応液を反応生成物濃度が約４５％付近になるまでそのまま濃縮し、更に室温（２５℃）で２４時間攪拌すると結晶が析出した。そこでこの結晶を濾過し、更に水洗及びトルエン洗浄した後乾燥すると白色結晶が４８．６ｇ（ＴＣＭＰ８６．３面積％、ＴＣＰ１３．７面積％）（ＴＣＭＰ収率５３．８％）得られた。
【００３０】
この結晶に１，４−ジオキサン２００ｇを加えて７０℃に加温溶解後、濃縮してから得られた油状物にアセトニトリル１００ｇを加えて加温再溶解した後、アセトニトリル約５０ｇを留去してから酢酸エチル５０ｇを加えて氷冷下で１時間攪拌してから室温（２５℃）で２０時間攪拌し再晶析させた。得られた結晶を濾過し、アセトニトリル洗浄した後乾燥することにより、白色結晶３８．７ｇ（ＴＣＭＰ９８．１面積％、ＴＣＰ１．９面積％）（ＴＣＭＰ収率４８．７％）が得られた。
【００３１】
比較例１
１０００ｍｌ耐熱ガラス製４つ口反応フラスコに７２％硝酸２８９ｇ（３．３０ｍｏｌ）とメタバナジン酸アンモニウム６５ｍｇ（０．１４３質量％）を仕込んだ。続いて攪拌しながら５０℃に昇温してからHDCP４５．０ｇ（０．３０ｍｏｌ）の滴下を開始した。注意深く滴下したにもかかわらず激しい発熱に伴い褐色ガスが飛散し内温は６０℃〜７０℃を超えた。５０℃に戻るのを待って、５０〜６０℃間で滴下終了まで８時間を要した（その温度制御が難しかった）。その後６０℃で２４時間攪拌を継続した。反応液の一部を採り、ガスクロマトグラフィー（ＧＣ）で分析の結果、未反応ＨＤＣＰは消失し、ＴＣＭＰ６０．７面積％、ＴＣＰ２８．３面積％であった。そこで反応を停止させ、反応液を反応生成物濃度が約４５％付近になるまでそのまま濃縮し、更に室温（２５℃）で２４時間攪拌すると結晶が析出した。そこでこの結晶を濾過し、更に水洗及びトルエン洗浄した後乾燥すると白色結晶が３８．４ｇ（ＴＣＭＰ８１．１面積％、ＴＣＰ１６．２面積％）（ＴＣＭＰ収率３９．９％）得られた。
【００３２】
この結晶に１，４−ジオキサン２００ｇを加えて７０℃に加温溶解後、濃縮してから得られた油状物にアセトニトリル１００ｇを加えて加温再溶解した後、アセトニトリル約５０ｇを留去してから酢酸エチル５０ｇを加えて氷冷下で１時間攪拌してから室温（２５℃）で２０時間攪拌し再晶析させた。得られた結晶を濾過し、アセトニトリル洗浄した後乾燥することにより、白色結晶２３．６ｇ（ＴＣＭＰ９２．１面積％、ＴＣＰ７．９面積％）（ＴＣＭＰ収率２４．９％）が得られた。
［バナジウム定量分析］
次に、この結晶の０．１ｇを採取し、０．１Ｍ硝酸で１０ｇとし、これをＩＣＰ−ＡＥＳで定量測定を行った。２回実施した分析値の平均値からバナジウムが１．４０ｐｐｍ含有していることが判明した。
【００３３】
以上から、公知の製造法では、結晶中のＴＣＰ含量が高く更に重金属の混入が避けられなかった。
【００３４】
【発明の効果】
反応条件の温和な条件への改良による温度制御の管理が容易で、副生物の抑制に伴う目的物収率の向上や副生ＮＯ₂ガス発生の減少、更に目的物中への不純金属の混入のない工業的製造法を提供できる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing an alicyclic tetracarboxylic acid. More specifically, the present invention relates to a process for producing 1,2,4-tricarboxy-3-carboxymethylcyclopentane (abbreviated as TCMP), characterized by nitric acid oxidation in the presence of a solvent of hydroxy-dicyclopentadiene without catalyst. .
[0002]
TCMP is a useful compound in the field of electronic materials as a raw material for polyimide, a curing agent for epoxy resin, and the like in terms of heat resistance, light transmission, electrical characteristics (insulation, dielectric constant), and the like.
[0003]
[Prior art]
Conventionally, as a method for producing TCMP, there is known a method in which hydroxy-dicyclopentadiene (abbreviated as HDCP) obtained by hydrating dicyclopentadiene (abbreviated as DCPD) is oxidized with nitric acid in the presence of a catalyst. (For example, see Patent Document 1 and Patent Document 2). However, both methods (1) dripping and charging HDCP into a large amount of nitric acid, causing intense heat generation and degassing, making temperature control during raw material charging difficult as the reaction scale increases, and rapidly A by-product of decarboxylated 1,2,3,4-tetracarboxycyclopentane (abbreviated as TCP) accompanying heat generation increases. Further, NO ₂ gas decomposed from nitric acid is scattered violently from the reaction tank, and there is a problem that the loss (therefore it is necessary to make a large excess of the charged amount) and trapping in the absorption tower.
(2) Since ammonium metavanadate is used as a catalyst, the product TCMP crystals crystallized from the highly concentrated nitric acid solution after the reaction can be mixed with vanadium metal even when washed with an organic solvent. It was regarded as a problem in the field of monomers such as materials.
[0004]
[Patent Document 1]
West German Patent Application Publication No. 1,078,120 [Patent Document 2]
Japanese Patent Application Laid-Open No. 60-13740
[Problems to be solved by the invention]
Easy control of temperature control by improving the reaction conditions to mild conditions, improving the yield of the target product due to the suppression of by-products, reducing the generation of by-product NO ₂ gas, and mixing impurities in the target product It is an object of the present invention to provide an industrial production method without any problem.
[0006]
[Means for Solving the Invention]
As a result of intensive research in order to solve the above-mentioned problems, the present inventor made an industrial operation surface by adding HDCP, which is a non-catalyzed raw material, in an organic solvent and dropping nitric acid into divided portions. The present invention has found an economical production method that is advantageous in terms of yield and purification under the mild reaction conditions that can be carried out in the above.
[0007]
That is, the present invention relates to the following inventions (1) to (6).
(1) Formula [1]
[0008]
[Chemical 3]

[0009]
Wherein the hydroxy-dicyclopentadiene represented by the formula is oxidized with nitric acid in the presence of a solvent in the absence of a catalyst [2]
[0010]
[Formula 4]

[0011]
The manufacturing method of 1,2,4-tricarboxy-3-carboxymethylcyclopentane represented by these.
(2) Nitric acid is added dropwise in a mixed solution of hydroxy-dicyclopentadiene represented by the formula [1] and a solvent, and 1,2,4-tricarboxy-3-carboxymethylcyclo described in (1) above. A method for producing pentane.
(3) The solvent according to (1) or (2), wherein the solvent is at least one solvent selected from an aliphatic halogenated hydrocarbon compound, an aliphatic nitro compound, an aliphatic carboxylic acid compound, and an aliphatic sulfone compound. Of 1,2,4-tricarboxy-3-carboxymethylcyclopentane.
(4) The 1,2,4- as described in any one of (1) to (3), wherein the solvent is at least one solvent selected from 1,2-dichloroethane, nitromethane, acetic acid and sulfolane. A process for producing tricarboxy-3-carboxymethylcyclopentane.
(5) The process for producing 1,2,4-tricarboxy-3-carboxymethylcyclopentane according to any one of (1) to (4), wherein the reaction temperature is 45 to 70 ° C.
(6) In the process for producing 1,2,4-tricarboxy-3-carboxymethylcyclopentane according to any one of (1) to (5), the 1,2,4-tricarboxy obtained 1,2,4-tricarboxy- characterized by using 1,4-dioxane and acetonitrile or a mixed solvent of 1,4-dioxane, acetonitrile and ethyl acetate as a recrystallization solvent of -3-carboxymethylcyclopentane A process for producing 3-carboxymethylcyclopentane.
[0012]
The present invention will be described in detail below.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
The manufacturing method of TCMP of this invention is represented by the following route.
[0014]
[Chemical formula 5]

[0015]
The raw material HDCP can be easily produced by heating DCPD in an aqueous solution of nitric acid or sulfuric acid. Moreover, a commercial item can also be used as it is.
[0016]
The first of the present invention is the use of a solvent. The reaction between HDCP and nitric acid is accompanied by extremely intense heat generation in the absence of a solvent, and the reaction temperature is difficult to control. By-production of decarboxylated TCP due to this rapid temperature increase increases. Also, the loss of nitrate due to scattering of the generated decomposed NO ₂ gas carbon dioxide and nitric acid is large, require a large excess of nitric acid.
[0017]
Therefore, the rapid increase in temperature is mitigated by the presence of the solvent. In addition, the loss of nitric acid due to scattering due to the action of retaining nitric acid in the solvent is reduced. As the type of the solvent, for example, a compound that is stable in nitric acid is preferable, and specific examples include aliphatic halogenated hydrocarbon compounds, aliphatic nitro compounds, aliphatic carboxylic acid compounds, and aliphatic sulfone compounds. More specifically, aliphatic halogenated hydrocarbon compounds include 1,2-dichloroethane, 1,1,1-trichloroethane and 1,2,3-trichloropropane, and aliphatic nitro compounds include nitromethane, nitroethane and Examples of nitropropane and aliphatic carboxylic acid compounds include formic acid, acetic acid and propionic acid, and examples of aliphatic sulfone compounds include dimethyl sulfoxide and sulfolane. In particular, 1,2-dichloroethane, nitromethane, acetic acid and sulfolane are preferred. At least one kind of solvent selected from these solvents can be used.
[0018]
When the amount of the solvent is increased, the exotherm accompanying the dropwise addition of nitric acid becomes mild, but the reaction progress tends to be slow. Therefore, 1-10 mol times mass is preferable with respect to raw material HDCP, and 1-5 mass times is especially preferable. The presence of this solvent enables stable industrial operation and improves the yield of the target TCMP.
[0019]
The second aspect of the present invention has found that the reaction is possible even without a catalyst. When using conventional ammonium metavanadate, etc., the product TCMP crystals crystallized from the highly concentrated nitric acid solution after the reaction are mixed with vanadium metal even after washing with an organic solvent. It was regarded as a problem. Therefore, the reaction solution by gas chromatography (GC) indicates that this reaction proceeds at a rate almost the same as that in the presence of a conventional catalyst even in the absence of a catalyst by setting a predetermined reaction temperature, nitric acid amount, solvent amount, and the like. Confirmed from tracking. This avoided heavy metal contamination in the target product. Therefore, the application to the precision industrial field where mixing of a trace amount of metal is regarded as a problem has become possible.
[0020]
In this reaction, it is preferable to use inexpensive nitric acid as an oxidizing agent which cleaves the carbon-carbon bond to form a dicarboxylic acid. When the concentration is low, by-products of the intermediates increase and the selectivity of tetracarboxylic acids decreases, so a high concentration of 60 to 90% is preferable. If the charging amount is small, raw materials and intermediates remain, and if the temperature is raised, the by-product TCP increases, which is not preferable. On the other hand, the larger the reaction, the faster the reaction, but the removal of the residual nitric acid after the reaction becomes complicated. Therefore, 8 to 20 molar equivalents are preferable with respect to HDCP, and further 10 to 12 molar equivalents are economical and preferable.
[0021]
The third aspect of the present invention is the order of preparation. That is, a raw material HDCP and an organic solvent are charged into a reaction vessel, and then a nitric acid aqueous solution is dropped at a desired temperature while stirring (forward dropping method). The dropping needs to be performed while the reaction proceeds simultaneously with the dropping of the nitric acid aqueous solution, while the temperature rise due to the heat generation is controlled, and generally the dropping time tends to be longer as the reaction scale is larger. Usually, it is preferably performed over 2 to 10 hours.
[0022]
What is important in the present invention is the setting of the reaction temperature. The higher the temperature, the faster the reaction, but it is accompanied by by-product of decarboxylated TCP, and therefore the temperature is usually preferably 45 to 70 ° C, particularly preferably 50 to 65 ° C.
[0023]
The reaction time can be determined by tracking the reaction with gas chromatography (GC) or liquid chromatography (LC), but it can usually be completed in 4 to 30 hours. This reaction can be carried out at normal pressure or increased pressure, and can also be carried out batchwise or continuously.
[0024]
Isolation of the reaction product is carried out by concentrating the product concentration of the reaction solution to about 45% by mass after completion of the reaction and then allowing to stand at 15 to 30 ° C. for 15 hours or longer, usually 15 to 30 hours, or stirring. Since crystals are precipitated, they are separated by filtration, washed with water and toluene and dried to obtain white crystals of TCMP. Moreover, precipitation of a crystal | crystallization can also be accelerated | stimulated by performing crystallization operation after adding the crystal | crystallization of a product.
[0025]
Furthermore, when obtaining a high-purity product, the TCMP crude crystals are dissolved in 1,4-dioxane by heating and then recrystallized by adding acetonitrile or a mixture of acetonitrile and ethyl acetate while cooling and cooling to around room temperature. And can be purified.
[0026]
【Example】
Examples Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. The analytical methods used in the examples are as follows.
[1] Gas chromatography (GC)
Model: Shimadzu Corporation Product name GC-17A: Column: Capillary column CBP1-W25-100 (25m X 0.53mmφ X 1μm), Column temperature: 100 ℃ (holding 2min.) To 290 ℃ (holding 10min.), 8 ° C / min. (Temperature increase rate), inlet temperature: 290 ° C, detector temperature: 290 ° C, carrier gas: helium, detection method: FID method.
[2] Vanadium quantitative analysis sample was subjected to ICP-AES measurement after thermal decomposition with sulfuric acid and nitric acid.
ICP-AES: Seiko Instruments Inc. Product name VISTA PRO: Wavelength: 213.618nm, Calibration curve: Absolute calibration curve method [0027]
Example 1
HDCP 15.0 g (0.10 mol) and 1,2-dichloroethane (EDC) 45.0 g (3 times by weight) were charged in a 300 ml heat-resistant glass four-necked reaction flask. Subsequently, the temperature was raised to 50 ° C. while stirring, and then 95 g (1.10 mol) of 73% nitric acid was added dropwise. The internal temperature was increased to 55 ° C. along with the dropwise addition, and was dropped between 50 to 55 ° C. over 2 hours. Thereafter, the temperature was gradually raised to 60 ° C. and stirring was continued for 22 hours. A part of the reaction solution was taken and analyzed by gas chromatography (GC). As a result, unreacted HDCP disappeared, and TCMP was 77.2 area% and TCP was 14.9 area%. Therefore, the reaction was stopped, and the reaction solution was concentrated as it was until the reaction product concentration was about 45%, and further stirred at room temperature (25 ° C.) for 24 hours to precipitate crystals. The crystals were filtered, washed with water and washed with toluene, and dried to obtain 16.8 g of white crystals (TCMP 90.2 area%, TCP 9.8 area%) (TCMP yield 58.3%).
[0028]
To this crystal, 84 g of 1,4-dioxane was added and dissolved by heating to 70 ° C., and after concentration, 30 g of acetonitrile was added to the oily substance obtained by reconstitution, followed by stirring for 1 hour under ice cooling. Then, recrystallization was performed with stirring at room temperature (25 ° C.) for 20 hours. The obtained crystals were filtered, washed with acetonitrile, and dried to obtain 13.0 g of white crystals (TCMP 100 area%) (TCMP yield 50.1%).
[0029]
Example 2
HDCP 45.0 g (0.30 mol) and 1,2-dichloroethane (EDC) 45.0 g (1 times by weight) were charged into a 1000 ml heat-resistant glass four-necked reaction flask. Subsequently, the temperature was raised to 50 ° C. while stirring, and then 297 g (3.30 mol) of 70% nitric acid was started to be dropped. The internal temperature was raised to 55 ° C. along with the dropwise addition, and was dropped over a period of 4 hours between 50 and 55 ° C. Thereafter, the temperature was gradually raised to 60 ° C. and stirring was continued for 24 hours. A part of the reaction solution was taken and analyzed by gas chromatography (GC). As a result, unreacted HDCP disappeared, and TCMP was 72.1 area% and TCP was 17.8 area%. Therefore, the reaction was stopped, and the reaction solution was concentrated as it was until the reaction product concentration was about 45%, and further stirred at room temperature (25 ° C.) for 24 hours to precipitate crystals. Therefore, the crystals were filtered, washed with water and washed with toluene, and dried to obtain 48.6 g of white crystals (TCMP 86.3 area%, TCP 13.7 area%) (TCMP yield 53.8%).
[0030]
200 g of 1,4-dioxane was added to this crystal and dissolved by heating to 70 ° C., and after concentration, 100 g of acetonitrile was added to the oily substance obtained by concentration and redissolved by heating. Then, about 50 g of acetonitrile was distilled off. Then, 50 g of ethyl acetate was added and the mixture was stirred for 1 hour under ice-cooling and then stirred for 20 hours at room temperature (25 ° C.) for recrystallization. The obtained crystals were filtered, washed with acetonitrile, and dried to obtain 38.7 g of white crystals (TCMP 98.1 area%, TCP 1.9 area%) (TCMP yield 48.7%).
[0031]
Comparative Example 1
A 4-ml reaction flask made of 1000 ml heat-resistant glass was charged with 289 g (3.30 mol) of 72% nitric acid and 65 mg (0.143% by mass) of ammonium metavanadate. Subsequently, the temperature was raised to 50 ° C. with stirring, and then dropwise addition of 45.0 g (0.30 mol) of HDCP was started. Despite careful dripping, brown gas was scattered with intense heat generation, and the internal temperature exceeded 60 ° C to 70 ° C. Waiting for the temperature to return to 50 ° C., it took 8 hours to complete the dropping between 50 ° C. and 60 ° C. (it was difficult to control the temperature). Thereafter, stirring was continued at 60 ° C. for 24 hours. A part of the reaction solution was taken and analyzed by gas chromatography (GC). As a result, unreacted HDCP disappeared, and TCMP was 60.7 area% and TCP was 28.3 area%. Therefore, the reaction was stopped, and the reaction solution was concentrated as it was until the reaction product concentration was about 45%, and further stirred at room temperature (25 ° C.) for 24 hours to precipitate crystals. Therefore, the crystals were filtered, washed with water and washed with toluene and dried to obtain 38.4 g of white crystals (TCMP 81.1 area%, TCP 16.2 area%) (TCMP yield 39.9%).
[0032]
200 g of 1,4-dioxane was added to this crystal and dissolved by heating to 70 ° C., and after concentration, 100 g of acetonitrile was added to the oily substance obtained by concentration and redissolved by heating. Then, about 50 g of acetonitrile was distilled off. Then, 50 g of ethyl acetate was added and the mixture was stirred for 1 hour under ice-cooling and then stirred for 20 hours at room temperature (25 ° C.) for recrystallization. The obtained crystals were filtered, washed with acetonitrile, and then dried to obtain 23.6 g of white crystals (TCMP 92.1 area%, TCP 7.9 area%) (TCMP yield 24.9%).
[Quantitative analysis of vanadium]
Next, 0.1 g of this crystal was collected and made 10 g with 0.1 M nitric acid, and this was quantitatively measured with ICP-AES. It was found that vanadium contained 1.40 ppm from the average value of the analytical values carried out twice.
[0033]
From the above, in the known production method, the TCP content in the crystal is high, and further mixing of heavy metals cannot be avoided.
[0034]
【The invention's effect】
Easy control of temperature control by improving the reaction conditions to mild conditions, improving the yield of the target product due to the suppression of by-products, reducing the generation of by-product NO ₂ gas, and mixing impurities in the target product An industrial manufacturing method without any problem can be provided.

Claims (4)

Formula [1]

Hydroxyl-dicyclopentadiene represented by the formula is oxidized by dropping nitric acid without catalyst in the presence of at least one solvent selected from aliphatic halogenated hydrocarbon compounds, aliphatic nitro compounds and aliphatic sulfone compounds. Formula [2] characterized by

The manufacturing method of 1,2,4-tricarboxy-3-carboxymethylcyclopentane represented by these. The solvent is 1,2-dichloroethane, the preparation of 1,2,4-tricarboxy-3-carboxymethyl-cyclopentane according to claim 1 is at least one solvent selected from among Nitorometa down及 beauty sulfolane. The method for producing 1,2,4-tricarboxy-3-carboxymethylcyclopentane according to any one of claims 1 to 2 , wherein the reaction temperature is 45 to 70 ° C. A 1,2,4-tricarboxy-3-carboxymethylcyclopentane is produced by the production method according to any one of claims 1 to 3 , and then 1,4-dioxane and acetonitrile are used as a recrystallization solvent. Or a method for producing 1,2,4-tricarboxy-3-carboxymethylcyclopentane, which is purified using a mixed solvent of 1,4-dioxane and acetonitrile and ethyl acetate.