JPH0468301B2 - - Google Patents
Info
- Publication number
- JPH0468301B2 JPH0468301B2 JP58059945A JP5994583A JPH0468301B2 JP H0468301 B2 JPH0468301 B2 JP H0468301B2 JP 58059945 A JP58059945 A JP 58059945A JP 5994583 A JP5994583 A JP 5994583A JP H0468301 B2 JPH0468301 B2 JP H0468301B2
- Authority
- JP
- Japan
- Prior art keywords
- dhna
- crude
- aqueous solution
- salt
- alkali metal
- 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.)
- Expired - Lifetime
Links
- 239000007864 aqueous solution Substances 0.000 claims description 26
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 22
- 238000000034 method Methods 0.000 claims description 20
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 13
- 239000001569 carbon dioxide Substances 0.000 claims description 11
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 11
- VOJUXHHACRXLTD-UHFFFAOYSA-N 1,4-dihydroxy-2-naphthoic acid Chemical compound C1=CC=CC2=C(O)C(C(=O)O)=CC(O)=C21 VOJUXHHACRXLTD-UHFFFAOYSA-N 0.000 claims description 9
- 239000012535 impurity Substances 0.000 claims description 9
- 150000001339 alkali metal compounds Chemical class 0.000 claims description 8
- 150000003839 salts Chemical class 0.000 claims description 8
- PCILLCXFKWDRMK-UHFFFAOYSA-N naphthalene-1,4-diol Chemical compound C1=CC=C2C(O)=CC=C(O)C2=C1 PCILLCXFKWDRMK-UHFFFAOYSA-N 0.000 claims description 6
- 239000013078 crystal Substances 0.000 claims description 3
- 239000011541 reaction mixture Substances 0.000 claims description 2
- USZZLTVYRPLBMB-UHFFFAOYSA-N 1,3-dihydroxynaphthalene-2-carboxylic acid Chemical compound C1=CC=CC2=C(O)C(C(=O)O)=C(O)C=C21 USZZLTVYRPLBMB-UHFFFAOYSA-N 0.000 claims 1
- 238000001816 cooling Methods 0.000 claims 1
- VOJUXHHACRXLTD-UHFFFAOYSA-M 1,4-dihydroxy-2-naphthoate Chemical compound C1=CC=C2C(O)=CC(C([O-])=O)=C(O)C2=C1 VOJUXHHACRXLTD-UHFFFAOYSA-M 0.000 description 50
- 108010065780 2-amino-4-hydroxy-6-hydroxymethyldihydropteridine pyrophosphokinase Proteins 0.000 description 47
- 108010089355 dihydroneopterin aldolase Proteins 0.000 description 47
- -1 alkali metal salt Chemical class 0.000 description 14
- 239000003960 organic solvent Substances 0.000 description 10
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 9
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 9
- 229910052783 alkali metal Inorganic materials 0.000 description 9
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 8
- 150000002576 ketones Chemical class 0.000 description 8
- 238000006243 chemical reaction Methods 0.000 description 7
- 239000003638 chemical reducing agent Substances 0.000 description 7
- 150000002148 esters Chemical class 0.000 description 7
- 239000002904 solvent Substances 0.000 description 7
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 description 6
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 6
- 150000003863 ammonium salts Chemical class 0.000 description 6
- 239000007789 gas Substances 0.000 description 6
- 239000006227 byproduct Substances 0.000 description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- NTIZESTWPVYFNL-UHFFFAOYSA-N Methyl isobutyl ketone Chemical compound CC(C)CC(C)=O NTIZESTWPVYFNL-UHFFFAOYSA-N 0.000 description 4
- 238000000746 purification Methods 0.000 description 4
- 229910000029 sodium carbonate Inorganic materials 0.000 description 4
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- UIHCLUNTQKBZGK-UHFFFAOYSA-N Methyl isobutyl ketone Natural products CCC(C)C(C)=O UIHCLUNTQKBZGK-UHFFFAOYSA-N 0.000 description 3
- 238000006085 Schmidt reaction Methods 0.000 description 3
- 125000001931 aliphatic group Chemical group 0.000 description 3
- PGMYKACGEOXYJE-UHFFFAOYSA-N anhydrous amyl acetate Natural products CCCCCOC(C)=O PGMYKACGEOXYJE-UHFFFAOYSA-N 0.000 description 3
- 125000004432 carbon atom Chemical group C* 0.000 description 3
- 235000014113 dietary fatty acids Nutrition 0.000 description 3
- GRWZHXKQBITJKP-UHFFFAOYSA-L dithionite(2-) Chemical class [O-]S(=O)S([O-])=O GRWZHXKQBITJKP-UHFFFAOYSA-L 0.000 description 3
- 229930195729 fatty acid Natural products 0.000 description 3
- 239000000194 fatty acid Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000011084 recovery Methods 0.000 description 3
- 229920006395 saturated elastomer Polymers 0.000 description 3
- JVBXVOWTABLYPX-UHFFFAOYSA-L sodium dithionite Chemical compound [Na+].[Na+].[O-]S(=O)S([O-])=O JVBXVOWTABLYPX-UHFFFAOYSA-L 0.000 description 3
- HXVNBWAKAOHACI-UHFFFAOYSA-N 2,4-dimethyl-3-pentanone Chemical compound CC(C)C(=O)C(C)C HXVNBWAKAOHACI-UHFFFAOYSA-N 0.000 description 2
- KWOLFJPFCHCOCG-UHFFFAOYSA-N Acetophenone Chemical compound CC(=O)C1=CC=CC=C1 KWOLFJPFCHCOCG-UHFFFAOYSA-N 0.000 description 2
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 description 2
- NIQCNGHVCWTJSM-UHFFFAOYSA-N Dimethyl phthalate Chemical compound COC(=O)C1=CC=CC=C1C(=O)OC NIQCNGHVCWTJSM-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 description 2
- 125000000217 alkyl group Chemical group 0.000 description 2
- 150000008365 aromatic ketones Chemical class 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- BGTOWKSIORTVQH-UHFFFAOYSA-N cyclopentanone Chemical compound O=C1CCCC1 BGTOWKSIORTVQH-UHFFFAOYSA-N 0.000 description 2
- FLKPEMZONWLCSK-UHFFFAOYSA-N diethyl phthalate Chemical compound CCOC(=O)C1=CC=CC=C1C(=O)OCC FLKPEMZONWLCSK-UHFFFAOYSA-N 0.000 description 2
- MTZQAGJQAFMTAQ-UHFFFAOYSA-N ethyl benzoate Chemical compound CCOC(=O)C1=CC=CC=C1 MTZQAGJQAFMTAQ-UHFFFAOYSA-N 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- MLFHJEHSLIIPHL-UHFFFAOYSA-N isoamyl acetate Chemical compound CC(C)CCOC(C)=O MLFHJEHSLIIPHL-UHFFFAOYSA-N 0.000 description 2
- QPJVMBTYPHYUOC-UHFFFAOYSA-N methyl benzoate Chemical compound COC(=O)C1=CC=CC=C1 QPJVMBTYPHYUOC-UHFFFAOYSA-N 0.000 description 2
- FDPIMTJIUBPUKL-UHFFFAOYSA-N pentan-3-one Chemical compound CCC(=O)CC FDPIMTJIUBPUKL-UHFFFAOYSA-N 0.000 description 2
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 2
- 239000012266 salt solution Substances 0.000 description 2
- 159000000000 sodium salts Chemical class 0.000 description 2
- 235000010265 sodium sulphite Nutrition 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- VLNUTKMHYLQCQB-UHFFFAOYSA-N 2,2-dimethylpentan-3-one Chemical compound CCC(=O)C(C)(C)C VLNUTKMHYLQCQB-UHFFFAOYSA-N 0.000 description 1
- QQZOPKMRPOGIEB-UHFFFAOYSA-N 2-Oxohexane Chemical compound CCCCC(C)=O QQZOPKMRPOGIEB-UHFFFAOYSA-N 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-M Bicarbonate Chemical compound OC([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-M 0.000 description 1
- DKPFZGUDAPQIHT-UHFFFAOYSA-N Butyl acetate Natural products CCCCOC(C)=O DKPFZGUDAPQIHT-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- JGFBQFKZKSSODQ-UHFFFAOYSA-N Isothiocyanatocyclopropane Chemical compound S=C=NC1CC1 JGFBQFKZKSSODQ-UHFFFAOYSA-N 0.000 description 1
- RJUFJBKOKNCXHH-UHFFFAOYSA-N Methyl propionate Chemical compound CCC(=O)OC RJUFJBKOKNCXHH-UHFFFAOYSA-N 0.000 description 1
- XBDQKXXYIPTUBI-UHFFFAOYSA-N Propionic acid Chemical class CCC(O)=O XBDQKXXYIPTUBI-UHFFFAOYSA-N 0.000 description 1
- UIIMBOGNXHQVGW-DEQYMQKBSA-M Sodium bicarbonate-14C Chemical compound [Na+].O[14C]([O-])=O UIIMBOGNXHQVGW-DEQYMQKBSA-M 0.000 description 1
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical class OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 description 1
- 150000001242 acetic acid derivatives Chemical class 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 238000003916 acid precipitation Methods 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 150000001447 alkali salts Chemical class 0.000 description 1
- 150000003868 ammonium compounds Chemical class 0.000 description 1
- 229940072049 amyl acetate Drugs 0.000 description 1
- 159000000032 aromatic acids Chemical class 0.000 description 1
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 1
- 239000012298 atmosphere Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 150000004648 butanoic acid derivatives Chemical class 0.000 description 1
- 229940043232 butyl acetate Drugs 0.000 description 1
- PWLNAUNEAKQYLH-UHFFFAOYSA-N butyric acid octyl ester Natural products CCCCCCCCOC(=O)CCC PWLNAUNEAKQYLH-UHFFFAOYSA-N 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 238000006473 carboxylation reaction Methods 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 150000008280 chlorinated hydrocarbons Chemical class 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 239000012043 crude product Substances 0.000 description 1
- 238000010908 decantation Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- FBSAITBEAPNWJG-UHFFFAOYSA-N dimethyl phthalate Natural products CC(=O)OC1=CC=CC=C1OC(C)=O FBSAITBEAPNWJG-UHFFFAOYSA-N 0.000 description 1
- 229960001826 dimethylphthalate Drugs 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 150000002168 ethanoic acid esters Chemical class 0.000 description 1
- 229940093499 ethyl acetate Drugs 0.000 description 1
- 150000004665 fatty acids Chemical class 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- NGAZZOYFWWSOGK-UHFFFAOYSA-N heptan-3-one Chemical compound CCCCC(=O)CC NGAZZOYFWWSOGK-UHFFFAOYSA-N 0.000 description 1
- MNWFXJYAOYHMED-UHFFFAOYSA-M heptanoate Chemical compound CCCCCCC([O-])=O MNWFXJYAOYHMED-UHFFFAOYSA-M 0.000 description 1
- FUZZWVXGSFPDMH-UHFFFAOYSA-N hexanoic acid Chemical compound CCCCCC(O)=O FUZZWVXGSFPDMH-UHFFFAOYSA-N 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 229940117955 isoamyl acetate Drugs 0.000 description 1
- JMMWKPVZQRWMSS-UHFFFAOYSA-N isopropanol acetate Natural products CC(C)OC(C)=O JMMWKPVZQRWMSS-UHFFFAOYSA-N 0.000 description 1
- 229940011051 isopropyl acetate Drugs 0.000 description 1
- GWYFCOCPABKNJV-UHFFFAOYSA-N isovaleric acid Chemical compound CC(C)CC(O)=O GWYFCOCPABKNJV-UHFFFAOYSA-N 0.000 description 1
- 229910003002 lithium salt Inorganic materials 0.000 description 1
- 159000000002 lithium salts Chemical class 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229940095102 methyl benzoate Drugs 0.000 description 1
- 229940017219 methyl propionate Drugs 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- 239000012046 mixed solvent Substances 0.000 description 1
- YKYONYBAUNKHLG-UHFFFAOYSA-N n-Propyl acetate Natural products CCCOC(C)=O YKYONYBAUNKHLG-UHFFFAOYSA-N 0.000 description 1
- UUIQMZJEGPQKFD-UHFFFAOYSA-N n-butyric acid methyl ester Natural products CCCC(=O)OC UUIQMZJEGPQKFD-UHFFFAOYSA-N 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 229910000028 potassium bicarbonate Inorganic materials 0.000 description 1
- 235000015497 potassium bicarbonate Nutrition 0.000 description 1
- 239000011736 potassium bicarbonate Substances 0.000 description 1
- 229910000027 potassium carbonate Inorganic materials 0.000 description 1
- 235000011181 potassium carbonates Nutrition 0.000 description 1
- HEZHYQDYRPUXNJ-UHFFFAOYSA-L potassium dithionite Chemical compound [K+].[K+].[O-]S(=O)S([O-])=O HEZHYQDYRPUXNJ-UHFFFAOYSA-L 0.000 description 1
- TYJJADVDDVDEDZ-UHFFFAOYSA-M potassium hydrogencarbonate Chemical compound [K+].OC([O-])=O TYJJADVDDVDEDZ-UHFFFAOYSA-M 0.000 description 1
- 159000000001 potassium salts Chemical class 0.000 description 1
- BHZRJJOHZFYXTO-UHFFFAOYSA-L potassium sulfite Chemical compound [K+].[K+].[O-]S([O-])=O BHZRJJOHZFYXTO-UHFFFAOYSA-L 0.000 description 1
- 235000019252 potassium sulphite Nutrition 0.000 description 1
- 229940090181 propyl acetate Drugs 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 229910000030 sodium bicarbonate Inorganic materials 0.000 description 1
- 235000017557 sodium bicarbonate Nutrition 0.000 description 1
- 235000017550 sodium carbonate Nutrition 0.000 description 1
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 description 1
- 235000019345 sodium thiosulphate Nutrition 0.000 description 1
- LSNNMFCWUKXFEE-UHFFFAOYSA-L sulfite Chemical class [O-]S([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-L 0.000 description 1
- 150000004764 thiosulfuric acid derivatives Chemical class 0.000 description 1
- NQPDZGIKBAWPEJ-UHFFFAOYSA-N valeric acid Chemical compound CCCCC(O)=O NQPDZGIKBAWPEJ-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
【発明の詳細な説明】
本発明は、粗製１，４−ジヒドロキシ−２−ナ
フトエ酸（以下、DHNAと略す）の精製法に関
する。更に詳しくは、１，４−ジヒドロキシナフ
タリンと炭酸ガスとをアルカリ性アルカリ金属化
合物の存在下、炭酸ガス加圧下で反応（コルベ・
シユミツト反応）させて得られる粗製１，４−ジ
ヒドロキシ−２−ナフトエ酸又はその塩の精製法
に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for purifying crude 1,4-dihydroxy-2-naphthoic acid (hereinafter abbreviated as DHNA). More specifically, 1,4-dihydroxynaphthalene and carbon dioxide are reacted under pressure of carbon dioxide in the presence of an alkaline alkali metal compound (Kolbe et al.
The present invention relates to a method for purifying crude 1,4-dihydroxy-2-naphthoic acid or a salt thereof obtained by conducting the Schmitt reaction.
DHNAの製造方法としては、一般にいわゆる
コルベ・シユミツト反応で製造される。例えば、
１，４−ジヒドロキシナフタリン（１，４−ナフ
トハイドロキノン、以下NHQと略す）の金属塩
と炭酸ガスにより製造する方法（Russing，J.
Prakt.Chem.〔２〕6230（1900））及びNHQと微粒
子状の無水炭酸カリウムとを非水系有機媒体中に
分散させ、炭酸ガス加圧下でカルボキシル化して
DHNAを製造する方法（園田ら（特開昭57−
126443及び特開昭57−128655））が開示されてい
る。さらに、本発明者らはNHQをアルカリ金属
化合物及び水の存在下炭酸ガス加圧下で、反応さ
せる方法（特願昭58−13651）を提案した。 DHNA is generally produced by the so-called Kolbe-Schmidt reaction. for example,
A method for producing 1,4-dihydroxynaphthalene (1,4-naphthohydroquinone, hereinafter abbreviated as NHQ) using a metal salt and carbon dioxide gas (Russing, J.
Prakt .
Method for producing DHNA (Sonoda et al.
No. 126443 and Japanese Unexamined Patent Publication No. 128655)) are disclosed. Furthermore, the present inventors proposed a method (Japanese Patent Application No. 13651/1982) in which NHQ is reacted in the presence of an alkali metal compound and water under pressure of carbon dioxide gas.
しかしながら、これらの方法により得られる粗
製DHNAには、副反応による副生成物と場合に
より原料NHQ及びNHQ中の不純物等が４〜８
％含まれる。従つて、高純度のDHNAを得るた
めには精製する必要がある。 However, the crude DHNA obtained by these methods contains by-products due to side reactions and, in some cases, raw material NHQ and impurities in NHQ.
%included. Therefore, in order to obtain highly pure DHNA, it is necessary to purify it.
本発明者等は、これら上記の方法で得られる粗
製DHNAを精製する方法について検討した。先
ず、従来一般的に行われている有機溶媒（例えば
メタノール等のアルコールとベンゼン等の芳香族
炭化水素の混合溶媒）による再結晶法では、純度
が１〜２％しか向上せず、DHNAの回収率も良
くなかつた。次に、粗製DHNAをアルカリ水溶
液に溶解した後、活性炭で処理し濾過し、その濾
液を酸析してDHNAを晶出させたが、得られた
DHNAの純度は向上しなかつた。 The present inventors investigated methods for purifying crude DHNA obtained by the above-mentioned methods. First, the conventional recrystallization method using an organic solvent (for example, a mixed solvent of an alcohol such as methanol and an aromatic hydrocarbon such as benzene) improves the purity by only 1 to 2%, making it difficult to recover DHNA. The rate was also not good. Next, crude DHNA was dissolved in an alkaline aqueous solution, treated with activated carbon and filtered, and the filtrate was precipitated with acid to crystallize DHNA.
The purity of DHNA was not improved.
本発明者らは、これら従来一般的に行なわれて
いる精製法の欠点を克服するべく、さら鋭意研究
した結果、粗製DHNAのアルカリ金属塩又はア
ンモニウム塩の水溶液を水と相溶性がないケトン
類又はエステル類を溶媒として用いて処理する
と、粗製DHNA中のNHQ及び反応中に生成した
副生成物のみが選択的に溶媒に抽出され、
DHNA塩を含む水層を分離し、必要により酸析
することにより高純度のDHNAが高収率で得ら
れることを見出し、本発明を完成した。 In order to overcome the drawbacks of these conventional purification methods, the present inventors conducted further intensive research and found that an aqueous solution of an alkali metal salt or ammonium salt of crude DHNA was used as a ketone that is not compatible with water. Alternatively, when treated with esters as a solvent, only NHQ in the crude DHNA and byproducts generated during the reaction are selectively extracted into the solvent.
The present invention was completed based on the discovery that highly purified DHNA can be obtained in high yield by separating the aqueous layer containing the DHNA salt and performing acid precipitation if necessary.
本発明は、NHQと炭酸ガスとをアルカリ性ア
ルカリ金属化合物の存在下、炭酸ガス加圧下で反
応（いわゆるコルベ・シユミツト反応）させて得
られる粗製DHNA又はその塩を精製するに当り、
該DHNAのアルカリ金属塩又はアンモニウム塩
の水溶液を還元剤の存在下又は不存在下、ケトン
類又はエステル類を用いて処理することを特徴と
する粗製DHNA又はその塩の精製法に存する。 The present invention relates to the purification of crude DHNA or its salt obtained by reacting NHQ and carbon dioxide gas under pressure with carbon dioxide gas in the presence of an alkaline alkali metal compound (so-called Kolbe-Schmidt reaction).
The present invention relates to a method for purifying crude DHNA or a salt thereof, which comprises treating an aqueous solution of the alkali metal salt or ammonium salt of DHNA with a ketone or an ester in the presence or absence of a reducing agent.
本発明に供する粗製DHNAは、NHQから、い
わゆるコルベ・シユミツト反応及びその改良法に
よつて製造される。例えば、前述のRussing及び
園田らの方法が挙げられる。その他、本発明者ら
の開発した次の方法がある。 The crude DHNA used in the present invention is produced from NHQ by the so-called Kolbe-Schmidt reaction and its improved method. For example, the method of Russing and Sonoda et al. mentioned above can be mentioned. In addition, there is the following method developed by the present inventors.
即ち、NHQをアルカリ性アルカリ金属化合物
及び水の存在下、炭酸ガス加圧下で反応させるこ
とからなるDHNAの製造方法である。この場合
の反応条件は、反応圧力が１〜50Kg／cm2Ｇ、反応
温度が100〜200℃、反応時間が30〜120分、アル
カリ金属化合物の使用量がNHQに対して等モル
倍以上、好ましくは２〜20モル倍、水の量が
NHQに対して２重量倍以上、好ましくは４〜20
重量倍で行なわれる。該方法は、好ましくは亜二
チオン酸ナトリウムなどの亜二チオン酸塩；亜硫
酸ナトリウムなどの亜硫酸塩等の還元剤の存在下
で行なわれる。還元剤は、一般に0.01％以上好ま
しくは0.05〜２％の水溶液として用いる。該アル
カリ性アルカリ金属化合物としては、一般に炭酸
ナトリウム、炭酸カリウム、重炭酸ナトリウム、
重炭酸カリウムなどの炭酸塩が有利に用いられ
る。この方法の場合、反応生成物は晶出する
NHQ及び重炭酸塩をデカンテーシヨン又は濾過
等の常法によつて分離することにより、粗製
DHNAのアルカリ金属塩の水溶液として得られ
るので、要すればそのまま本発明の方法に供する
ことができるので好都合である。 That is, the method for producing DHNA comprises reacting NHQ in the presence of an alkaline alkali metal compound and water under pressure of carbon dioxide gas. The reaction conditions in this case are a reaction pressure of 1 to 50 Kg/cm 2 G, a reaction temperature of 100 to 200°C, a reaction time of 30 to 120 minutes, an amount of the alkali metal compound used equal to or more than the equivalent mole of NHQ, Preferably 2 to 20 times the amount of water
At least 2 times the weight of NHQ, preferably 4 to 20
It is done by weight. The process is preferably carried out in the presence of a reducing agent such as a dithionite salt such as sodium dithionite; a sulfite salt such as sodium sulfite. The reducing agent is generally used as an aqueous solution of 0.01% or more, preferably 0.05 to 2%. The alkaline alkali metal compounds generally include sodium carbonate, potassium carbonate, sodium bicarbonate,
Carbonates such as potassium bicarbonate are advantageously used. In this method, the reaction product crystallizes
The crude product is obtained by separating NHQ and bicarbonate by conventional methods such as decantation or filtration.
Since it is obtained as an aqueous solution of an alkali metal salt of DHNA, it is convenient because it can be used as is in the method of the present invention if necessary.
粗製DHNAを用いる場合は、粗製DHNAをア
ルカリ性水溶液に溶解する。 When using crude DHNA, dissolve the crude DHNA in an alkaline aqueous solution.
しかして、得られる粗製DHNAのアルカリ金
属塩又はアンモニウム塩水溶液を構成するアルカ
リ金属塩としてはナトリウム塩、カリウム塩、リ
チウム塩が挙げられるが、通常は安価なナトリウ
ム塩が用いられる。 The alkali metal salts constituting the aqueous alkali metal salt or ammonium salt solution of the crude DHNA thus obtained include sodium salts, potassium salts, and lithium salts, and usually inexpensive sodium salts are used.
この粗製DHNAをアルカリ性アルカリ金属又
はアンモニウム化合物水溶液を用いて溶解する場
合は、該アルカリ水溶液としては水酸化物水溶液
を用いることもできるが、比較的温和な炭酸ナト
リウム、重炭酸ナトリウムなどの水溶液を粗製
DHNAに対して中和当量以上、一般に過剰量好
ましくは1.2〜2.0当量倍用いるのが好ましい。 When this crude DHNA is dissolved using an alkaline alkali metal or ammonium compound aqueous solution, a hydroxide aqueous solution can be used as the alkaline aqueous solution, but a relatively mild aqueous solution such as sodium carbonate or sodium bicarbonate can be used as the crude alkali aqueous solution.
It is preferable to use a neutralizing equivalent or more of DHNA, generally an excess amount, preferably 1.2 to 2.0 equivalents.
粗製DHNA塩の水溶液の濃度は、常識的に溶
解度以下であればよいが、工業的には経済性の上
から通常３％以上好ましくは５％以上である。 The concentration of the aqueous solution of the crude DHNA salt should be no more than the solubility in common sense, but from the viewpoint of economic efficiency, it is usually 3% or more, preferably 5% or more.
DHNAはアルカリ性水溶液中では非常に酸化
され易いため、還元剤を含む水溶液を用いるのが
好ましく、還元剤の量は特に限定されないが、好
ましくは0.01％以上、さらに好ましくは0.05〜２
％の水溶液になるようにもちいる。 Since DHNA is very easily oxidized in an alkaline aqueous solution, it is preferable to use an aqueous solution containing a reducing agent, and the amount of the reducing agent is not particularly limited, but is preferably 0.01% or more, more preferably 0.05 to 2%.
% aqueous solution.
該還元剤としては、水の存在下で酸素を還元吸
収し得るような還元剤、例えば亜二チオン酸ナト
リウム、亜二チオン酸カリウムなどの亜二チオン
酸塩；亜硫酸ナトリウム、亜硫酸カリウムなどの
亜硫酸塩；チオ硫酸ナトリウムなどのチオ硫酸塩
などが挙げられる。 The reducing agent includes a reducing agent capable of reducing and absorbing oxygen in the presence of water, such as dithionite salts such as sodium dithionite and potassium dithionite; sulfites such as sodium sulfite and potassium sulfite. Salt; Examples include thiosulfates such as sodium thiosulfate.
本発明に用いられる溶媒としては、実質的に水
と相溶性のない有機溶媒であり、しかも粗製
DHNA塩の水溶液と処理したときにNHQ及び副
生成物などの不純物のみが選択的に有機溶媒に抽
出されるようなものである。この要件に適合する
のは、ケトン類とエステル類であり、ベンゼンな
どの炭化水素、塩化メチレン、クロロホルムなど
の塩素化炭化水素などでは純度が思うように向上
しない。 The solvent used in the present invention is an organic solvent that is substantially incompatible with water, and is a crude solvent.
When treated with an aqueous solution of DHNA salt, only impurities such as NHQ and by-products are selectively extracted into an organic solvent. Ketones and esters meet this requirement; hydrocarbons such as benzene and chlorinated hydrocarbons such as methylene chloride and chloroform do not improve purity as expected.
ケトン類としては、例えば脂肪族飽和ケトン、
脂環式ケトン、芳香族ケトンがあげられる。 Examples of ketones include aliphatic saturated ketones,
Examples include alicyclic ketones and aromatic ketones.
脂肪族飽和ケトンとしては、一般式R1COR2
〔但し、R1及びR2は炭素数２〜５のアルキル基を
表す〕の化合物が、水に対する非相溶性及び不純
物に対する溶解性が比較的大きいので好ましく、
炭素数が小さいと水に溶解し、大きくなると不純
物の溶解度が小さくなる。該ケトンとしては、例
えばジエチルケトン、ジイソプロピルケトン、イ
ソブチルメチルケトン、ブチルメチルケトン、ブ
チルエチルケトン、ｔ−ブチルエチルケトンが挙
げられる。 For aliphatic saturated ketones, the general formula R 1 COR 2
The compound [wherein R 1 and R 2 represent an alkyl group having 2 to 5 carbon atoms] is preferable because it has relatively high incompatibility with water and solubility with respect to impurities.
If the carbon number is small, it will dissolve in water, and if the carbon number is large, the solubility of impurities will be reduced. Examples of the ketone include diethyl ketone, diisopropyl ketone, isobutyl methyl ketone, butyl methyl ketone, butyl ethyl ketone, and t-butyl ethyl ketone.
脂環式ケトンとしては、例えばシクロペンタノ
ン、芳香族ケトンとしては、例えばアセトフエノ
ンが挙げられる。 Examples of alicyclic ketones include cyclopentanone, and examples of aromatic ketones include acetophenone.
実用的には、脂肪族飽和ケトン、特に好ましく
はイソブチルメチルケトン（MIBK）が好まし
い。 Practically speaking, aliphatic saturated ketones are preferred, particularly isobutyl methyl ketone (MIBK).
エステル類としては、例えば脂肪酸のエステ
ル、芳香族酸のエステルが挙げられる。 Examples of esters include fatty acid esters and aromatic acid esters.
脂肪酸のエステルとしては、一般式R3COOR4
〔但し、R3及びR4はそれぞれ炭素数１〜５のアル
キル基を表す〕の化合物が水に対する非相溶性及
び不純物に対する溶解性が比較的大きいので好ま
しく、炭素数が大きくなると不純物の溶解度が小
さくなる。 As esters of fatty acids, the general formula R 3 COOR 4
[However, R 3 and R 4 each represent an alkyl group having 1 to 5 carbon atoms] is preferable because it has relatively high incompatibility with water and relatively high solubility to impurities, and as the number of carbon atoms increases, the solubility of impurities decreases. becomes smaller.
該エステルとしては、例えば酢酸エチル、酢酸
プロピル、酢酸イソプロピル、酢酸ブチル、酢酸
アミル、酢酸イソアミル、酢酸ペンチル、などの
酢酸エステル；プロピオン酸メチルなどのプロピ
オン酸エステル；酪酸メチルなどの酪酸エステル
が挙げられる。 Examples of the ester include acetate esters such as ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, amyl acetate, isoamyl acetate, and pentyl acetate; propionate esters such as methyl propionate; butyrate esters such as methyl butyrate. .
芳香族酸エステルとしては、比較的沸点の低い
低級なエステルが好ましく、例えば安息香酸メチ
ル、安息香酸エチル、フタル酸ジメチル、フタル
酸ジエチルなどが挙げられる。 The aromatic acid ester is preferably a lower ester having a relatively low boiling point, such as methyl benzoate, ethyl benzoate, dimethyl phthalate, diethyl phthalate, and the like.
実用的には、脂肪酸エステル、特に酢酸エステ
ル類が好ましい。 Practically speaking, fatty acid esters, particularly acetic acid esters, are preferred.
本発明に用いる前記の有機溶媒の使用量は、特
に限定されないが一般に粗製DHNA中の不純物
を溶解し、目的の純度を保証しうるだけの量が用
いられ、溶媒の種類によつても異なるが、通常は
粗製DHNAに対して同重量倍以上、50重量倍以
下が用いられる。 The amount of the organic solvent used in the present invention is not particularly limited, but is generally an amount sufficient to dissolve impurities in the crude DHNA and ensure the desired purity, although it varies depending on the type of solvent. Usually, it is used in an amount of not less than the same weight and not more than 50 times the weight of crude DHNA.
本発明において、粗製DHNAのアルカリ金属
塩又はアンモニウム塩の水溶液を前記有機溶媒で
処理する方法は、一般に次のように実施する。 In the present invention, the method of treating an aqueous solution of a crude alkali metal salt or ammonium salt of DHNA with the organic solvent is generally carried out as follows.
粗製DHNAのアルカリ金属塩又はアンモニウ
ム塩の水溶液と該有機溶媒とを、不活性ガス雰囲
気下に十分に撹拌接触させ、不純物を抽出する。
この抽出操作は、通常室温〜50℃位で、数十分行
なえば十分である。抽出後、静置しNHQ及び副
生成物を含む溶媒層とDHNAのアルカリ金属塩
又はアンモニウム塩を含む水層とを分液し、該水
層を塩酸又は硫酸等の無機酸でPH2.0付近まで酸
性化し、晶出する結晶を濾過等で分離し、乾燥す
ることにより高純度のDHNAを取得することが
できる。なお、分液した有機溶媒層には、溶媒の
種類によつては多少のDHNAが存在するので、
これを弱アルカリ性水溶液又は水で再抽出して、
最初の水層に加えるような回収法も採りうる。し
かして、得られるDHNAは純度約99％の高純度
のものである。 An aqueous solution of a crude alkali metal salt or ammonium salt of DHNA and the organic solvent are brought into contact with sufficient stirring under an inert gas atmosphere to extract impurities.
It is sufficient to carry out this extraction operation for several tens of minutes, usually at room temperature to about 50°C. After extraction, leave to stand and separate the solvent layer containing NHQ and by-products from the aqueous layer containing an alkali metal salt or ammonium salt of DHNA, and add the aqueous layer to a pH of around 2.0 with an inorganic acid such as hydrochloric acid or sulfuric acid. Highly pure DHNA can be obtained by acidifying the solution to 100%, separating the crystallized crystals by filtration, etc., and drying them. Note that depending on the type of solvent, some DHNA may be present in the separated organic solvent layer.
Re-extract this with a weak alkaline aqueous solution or water,
Recovery methods such as addition to the initial aqueous layer may also be used. Thus, the obtained DHNA has a high purity of about 99%.
以上説明したように、本発明によれば、室温付
近の操作のみで容易に約99％という高純度の
DHNAを得ることができる。特に、NHQのカル
ボキシル化反応を水溶液中で実施する場合には、
反応終了後粗製DHNAがアルカリ塩水溶液とし
て得られるので、粗製DHNAを単離することな
く、該反応液を本発明の方法に従つて処理するこ
とにより、高純度のDHNAを得ることが可能で
あり、極めて工業的に有利である。 As explained above, according to the present invention, high purity of approximately 99% can be easily obtained by only operation near room temperature.
You can get DHNA. In particular, when carrying out the carboxylation reaction of NHQ in an aqueous solution,
After the reaction is completed, crude DHNA is obtained as an aqueous alkali salt solution, so it is possible to obtain highly pure DHNA by treating the reaction solution according to the method of the present invention without isolating the crude DHNA. , which is extremely industrially advantageous.
次に、実施例によつて本発明を詳細に説明す
る。本明細書においては、断らない限り「％」は
重量％を表す。 Next, the present invention will be explained in detail with reference to Examples. In this specification, unless otherwise specified, "%" represents % by weight.
実施例 １
粗製DHNA（純度93.6％、NHQ2.6％、副生成
物3.8％）3.50ｇを、炭酸ナトリウム1.40ｇを含む
0.1％ハイドロサルフアイト（亜二チオン酸ナト
リウム）水溶液40mlに窒素雰囲気中で溶解する。
酢酸エチル20mlを加え、40℃で15分間よく撹拌し
た後、静置して有機溶媒層と水層とを分離し、該
水層に30％硫酸水溶液をPH2.0になるまでくわえ、
DHNAを晶出させ、濾過、乾燥し、精製
DHNA3.12ｇ（純度99.5％）を得た。該精製
DHNAの回収率は94.8％であつた。Example 1 3.50 g of crude DHNA (93.6% purity, 2.6% NHQ, 3.8% by-products) containing 1.40 g of sodium carbonate
Dissolve in 40 ml of 0.1% hydrosulfite (sodium dithionite) aqueous solution in a nitrogen atmosphere.
After adding 20 ml of ethyl acetate and stirring well at 40°C for 15 minutes, leave it to stand to separate the organic solvent layer and the aqueous layer, and add 30% sulfuric acid aqueous solution to the aqueous layer until the pH reaches 2.0.
Crystallize DHNA, filter, dry, and purify
3.12 g of DHNA (purity 99.5%) was obtained. The purification
The recovery rate of DHNA was 94.8%.
実施例 ２
有機溶媒として、イソブチルメチルケトン20ml
を用いた以外は実施例１と同様に実施して、精製
DHNA3.10ｇ（純度99.7％）を得た。回収率は
94.6％であつた。Example 2 20 ml of isobutyl methyl ketone as organic solvent
Purification was carried out in the same manner as in Example 1 except that
3.10 g of DHNA (purity 99.7%) was obtained. The recovery rate is
It was 94.6%.
実施例 ３
DHNA12.0ｇ、炭酸ナトリウム47.7ｇ、水130
ｇを300mlガラス製オートクレーブに仕込み、炭
酸ガス10Kg／cm2Ｇで、145℃、１時間反応させた
後、40℃まで冷却し、放圧して、得られる反応混
合物より水溶液のみを窒素シールした容器に吸引
しながら取り出した。該水溶液に酢酸エチル30ml
を加え、40℃で15分間よく撹拌して静置し、分液
して得た水層に30％硫酸水溶液をPH2.0になるま
で加え、晶出する結晶を濾過、水洗し、乾燥して
DHNA6.5ｇ（純度99.2％）を得た。Example 3 DHNA 12.0g, sodium carbonate 47.7g, water 130g
g into a 300 ml glass autoclave, reacted with carbon dioxide gas 10 Kg/cm 2 G at 145°C for 1 hour, cooled to 40°C, depressurized, and removed only the aqueous solution from the resulting reaction mixture into a nitrogen-sealed container. It was removed while being suctioned. Add 30 ml of ethyl acetate to the aqueous solution.
was added, stirred well for 15 minutes at 40℃ and allowed to stand, separated. To the resulting aqueous layer, 30% sulfuric acid aqueous solution was added until the pH reached 2.0, and the crystals that crystallized were filtered, washed with water, and dried. hand
6.5 g of DHNA (purity 99.2%) was obtained.
比較例 １
有機溶媒として、ベンゼン及び塩化メチレン各
20mlを用いた以外は、実施例１と同じ様に実施し
て、それぞれ純度95.5％のDHNA3.15ｇ及び純度
96.1％のDHNA3.11ｇを得た。Comparative Example 1 Benzene and methylene chloride were used as organic solvents.
The procedure was carried out in the same manner as in Example 1, except that 20 ml was used, and 3.15 g of DHNA with a purity of 95.5% and DHNA with a purity of 95.5% were used, respectively.
3.11 g of 96.1% DHNA was obtained.
Claims (1)
とをアルカリ性アルカリ金属化合物の存在下、炭
酸ガス加圧下で反応させて得られる粗製１，４−
ジヒドロキシ−２−ナフトエ酸又はその塩を精製
するに当り、該粗製１，４−ジヒドロキシ−２−
ナフトエ酸のアルカリ金属塩又はアンモニウム塩
の水溶液を、還元剤の存在下又は不存在下、ケト
ン類又はエステル類を用いて処理することを特徴
とする粗製１，４−ジヒドロキシ−２−ナフトエ
酸又はその塩の精製法。 ２ 粗製１，４−ジヒドロキシ−２−ナフトエ酸
の塩が、１，４−ジヒドロキシナフタリンをアル
カリ性アルカリ金属化合物及び水の存在下、炭酸
ガス加圧下で反応させたのち、反応混合物を冷却
し、生成した結晶と分離して得られる１，４−ジ
ヒドロキシ−２−ナフトエ酸塩及び不純物を含有
する水溶液である特許請求の範囲第１項記載の方
法。[Scope of Claims] 1. Crude 1,4-dihydroxynaphthalene obtained by reacting 1,4-dihydroxynaphthalene and carbon dioxide gas under pressure of carbon dioxide gas in the presence of an alkaline alkali metal compound.
In purifying dihydroxy-2-naphthoic acid or its salt, the crude 1,4-dihydroxy-2-
Crude 1,4-dihydroxy-2-naphthoic acid or How to purify the salt. 2 The salt of crude 1,4-dihydroxy-2-naphthoic acid is produced by reacting 1,4-dihydroxynaphthalene with an alkaline alkali metal compound and water under pressure of carbon dioxide gas, and then cooling the reaction mixture. The method according to claim 1, which is an aqueous solution containing the 1,4-dihydroxy-2-naphthoate obtained by separating the crystals and impurities.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5994583A JPS59186942A (en) | 1983-04-07 | 1983-04-07 | Purification of crude 1,4-dihydroxy-2-naphthoic acid or its salt |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5994583A JPS59186942A (en) | 1983-04-07 | 1983-04-07 | Purification of crude 1,4-dihydroxy-2-naphthoic acid or its salt |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59186942A JPS59186942A (en) | 1984-10-23 |
| JPH0468301B2 true JPH0468301B2 (en) | 1992-11-02 |
Family
ID=13127789
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5994583A Granted JPS59186942A (en) | 1983-04-07 | 1983-04-07 | Purification of crude 1,4-dihydroxy-2-naphthoic acid or its salt |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59186942A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0744419U (en) * | 1993-10-05 | 1995-11-21 | 久仁夫 大塚 | Perforated partition plate with two types of rice cookers for electric rice cookers |
| WO2003016544A1 (en) | 2001-08-10 | 2003-02-27 | Meiji Dairies Corporation | Process for producing 1,4-dihydroxy-2-naphthoic acid |
| WO2004085364A1 (en) | 2003-03-26 | 2004-10-07 | Meiji Dairies Corporation | Method of stabilizing 1,4-dihydroxy-2-naphthoic acid |
| CN100364518C (en) * | 2005-12-20 | 2008-01-30 | 西安交通大学 | Use of 1,4-naphthalene diphenol in preparing external use sperm killing contraceptive medicine of preventing and curing genital tract infection |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB638196A (en) * | 1948-05-08 | 1950-05-31 | Douglas James Fry | Improvements in or relating to the preparation of hydroxy aromatic carboxylic acids |
| JPS57126443A (en) * | 1981-01-29 | 1982-08-06 | Nippon Shokubai Kagaku Kogyo Co Ltd | Preparation of 1,4-dihydroxy-2-naphthoic acid |
-
1983
- 1983-04-07 JP JP5994583A patent/JPS59186942A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB638196A (en) * | 1948-05-08 | 1950-05-31 | Douglas James Fry | Improvements in or relating to the preparation of hydroxy aromatic carboxylic acids |
| JPS57126443A (en) * | 1981-01-29 | 1982-08-06 | Nippon Shokubai Kagaku Kogyo Co Ltd | Preparation of 1,4-dihydroxy-2-naphthoic acid |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59186942A (en) | 1984-10-23 |
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