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WO2012074168A1 - Procédé de préparation du 4-hydroxyiminobenzoate de méthyle - Google Patents

Procédé de préparation du 4-hydroxyiminobenzoate de méthyle Download PDF

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Publication number
WO2012074168A1
WO2012074168A1 PCT/KR2011/001051 KR2011001051W WO2012074168A1 WO 2012074168 A1 WO2012074168 A1 WO 2012074168A1 KR 2011001051 W KR2011001051 W KR 2011001051W WO 2012074168 A1 WO2012074168 A1 WO 2012074168A1
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WO
WIPO (PCT)
Prior art keywords
dmt
alcohol
methyl
filtrate
mhb
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.)
Ceased
Application number
PCT/KR2011/001051
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English (en)
Korean (ko)
Inventor
김우선
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SK Chemicals Co Ltd
NAF Co Ltd
Original Assignee
NAF Co Ltd
SK Petrochemical Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by NAF Co Ltd, SK Petrochemical Co Ltd filed Critical NAF Co Ltd
Publication of WO2012074168A1 publication Critical patent/WO2012074168A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C67/00—Preparation of carboxylic acid esters
    • C07C67/48—Separation; Purification; Stabilisation; Use of additives
    • C07C67/52—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C249/00—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton
    • C07C249/04—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton of oximes
    • C07C249/08—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton of oximes by reaction of hydroxylamines with carbonyl compounds
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C249/00—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton
    • C07C249/04—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton of oximes
    • C07C249/14—Separation; Purification; Stabilisation; Use of additives
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C251/00—Compounds containing nitrogen atoms doubly-bound to a carbon skeleton
    • C07C251/32—Oximes
    • C07C251/62—Oximes having oxygen atoms of oxyimino groups esterified
    • C07C251/64—Oximes having oxygen atoms of oxyimino groups esterified by carboxylic acids
    • C07C251/68—Oximes having oxygen atoms of oxyimino groups esterified by carboxylic acids with at least one of the esterifying carboxyl groups bound to a carbon atom of a six-membered aromatic ring
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C67/00—Preparation of carboxylic acid esters
    • C07C67/30—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group
    • C07C67/333—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group by isomerisation; by change of size of the carbon skeleton

Definitions

  • the present invention relates to a process for preparing methyl-4-hydroxyiminobenzoate (MHB) from a by-product resulting from dimethyl terephthalate production process. More specifically, the present invention relates to a process for the preparation of methyl-4-formylbenzoate ("MFB"), dimethyl terephthalate (DMT), methyl-p-toluate ) And the like. The present invention relates to a process for preparing and separating MHB from a by-product of a DMT production process.
  • MMB methyl-4-formylbenzoate
  • DMT dimethyl terephthalate
  • methyl-p-toluate methyl-p-toluate
  • Dimethyl terephthalate is a compound represented by the following formula (1) and is widely used as a raw material for polyester polymers for the production of polyester fibers, molded products and the like.
  • reaction by-products generated in the production of DMT include methyl benzoate, methylbenzoate, methyl-p-toluate (MPT), methyl-4-methylbenzoate -formylbenzoate, MFB), and it is also referred to as a crude MFB since it typically contains a large amount of MFB components.
  • MFB methyl-p-toluate
  • MFB methyl-4-methylbenzoate -formylbenzoate
  • methyl 4-hydroxyiminobenzoate is a major raw material for the production of 4- (aminomethyl) benzoic acid and 4- (aminomethyl) cyclohexanecarboxylic acid which are used as fiber modifiers, starting materials for polymers and medicinal intermediates
  • 4- (aminomethyl) benzoic acid and 4- (aminomethyl) cyclohexanecarboxylic acid which are used as fiber modifiers, starting materials for polymers and medicinal intermediates
  • the sulfite adduct of methyl 4-formylbenzoate which is a reaction intermediate, must be hydrolyzed under acidic or alkaline conditions.
  • acid hydrolysis a large amount of sulfur dioxide , A large amount of inorganic sulfurous acid waste water may be generated at the time of alkali hydrolysis, thereby causing environmental pollution problems.
  • yield of hydrolysis is low, a large amount of the separation filtrate is discharged into waste water having a high organic matter content, which is problematic in its effectiveness.
  • Korean Patent Publication Nos. 1995-0005193 and Korean Patent No. 0124964 disclose a process for producing 4-formylbenzoic acid from reaction by-products generated in a DMT production process. All of these processes are carried out at high temperature in a strong acid aqueous solution, , There are problems in industrialization due to generation of high concentration organic acid wastewater and a large amount of sulfur dioxide which is a toxic gas.
  • the recycling method of the reaction by-products in the DMT manufacturing process has a problem in that it is inexpensive in terms of environment and cost.
  • a specific example of the present invention is to provide a method for preparing, purifying or separating MHB of high purity from reaction by-products generated in a DMT production process.
  • the methylformyl benzoate-containing by-product is at least one selected from the group consisting of methyl formyl benzoate (MFB), dimethyl terephthalate (DMT), methyl benzoate (MBZ), and methyl-para- .
  • the alcohol is added to the crude MFB among the reaction by-products generated in the DMT production process, and the solubility of the reaction by-products in the DMT and other by-product components (for example, MFB)
  • the DMT contained in the reaction by-product can be recovered at a high purity of at least 90% by a simple process such as filtration after the addition of alcohol.
  • the filtrate is added with an inorganic acid salt of hydroxyamine or hydroxyamine
  • the MHB is produced by oxidizing the MFB in the filtrate, thereby providing a merit that a high-purity MHB can be produced through a simple and economical work-up process.
  • DMT and MHB of higher purity can be provided by a simple purification process as needed.
  • Typical DMT production processes involve oxidation and ester reactions sequentially with p-xylene as a starting material.
  • p-xylene is oxidized in liquid phase with terephthalic acid (or its intermediate p-formylbenzoic acid) (DMT, MBZ, MPT, etc.) in the presence of a large amount of MFB and a small amount of other components (for example, DMT, MBZ, MPT, etc.) And is referred to as crude MFB.
  • composition of such reaction byproducts may vary depending on the DMT preparation process, but typically ranges from about 60 to 90 wt% MFB, from about 5 to about 30 wt% DMT, from about 1 to about 8 wt% MPT, and from about 0.1 to about 3 MBZ % ≪ / RTI > by weight.
  • the above composition is provided for illustrative purposes, and the present invention is not necessarily limited thereto.
  • the alcohol is added to the reaction by-product of the DMT production process. Due to the difference in solubility of the components in the reaction by-product to the alcohol, the DMT is converted into a solid (solid) Is still in a dissolved state. Therefore, when the solid component and the filtrate are separated by using a filtration process, a filtrate containing solid components rich in DMT component and MFB and the like can be obtained, respectively.
  • an alcohol component may be added under stirring of the byproduct.
  • Examples of the alcohols to be added to the reaction by-products in the embodiment of the present invention include aliphatic alcohols of C 1 to C 10 , and specific examples thereof include methanol, ethanol, propanol, isopropanol, butanol, And more specifically, methanol can be used.
  • the above-listed alcohols are exemplarily described, and the present invention is not necessarily limited thereto.
  • the amount of alcohol added may range from about 0.2 to 5.0 ml / g, more specifically from about 0.5 to 2.0 ml / g, per gram of reaction by-product (or crude MFB).
  • the alcohol when the alcohol is not added in a sufficient amount or the alcohol is used in an excessively large amount, the DMT content in the filtrate increases with the increase of DMT which is not solidified, It can cause problems.
  • the above numerical ranges are illustrative, and the present invention is not necessarily limited thereto.
  • the temperature of the alcohol-added by-product can be adjusted to, for example, about -5 to 120 ° C, specifically about 3 to 50 ° C, so that the DMT can be recovered in high purity and high yield in the subsequent filtration step. This suggests that as the temperature increases, the amount of DMT dissolved in the alcohol increases, which may lower the recovery rate of DMT.
  • an efficient filtration method is important. Vacuum filtration, pressure filtration, centrifugal separation, Press method may be exemplified. At this time, the efficient filtering method may be pressurized filtration, wherein the pressure is, for example, about 0.5 to about 3 kg / cm 2 , specifically about 0.5 to about 1.5 kg / cm 2 Lt; / RTI >
  • the step of washing the solids obtained through the filtration step may be additionally performed in order to further increase the purity of the recovered DMT.
  • a usable washing component it may be preferable to use a kind of solvent capable of dissolving and removing other components (for example, MFB, etc.) while maintaining the amount of DMT in the solid content to the maximum.
  • Representative examples of the alcohol component have. This is because, when a soluble component for DMT is used, the recovery rate of DMT may be lowered.
  • the alcohols e.g., C 1 to C 10 aliphatic alcohols such as methanol, ethanol, propanol, isopropanol, butanol, mixtures thereof, etc.
  • the alcohols e.g., C 1 to C 10 aliphatic alcohols such as methanol, ethanol, propanol, isopropanol, butanol, mixtures thereof, etc.
  • the amount of the alcohol to be used may be about 0.1 to about 5 times, more specifically about 0.5 to about 1.0 times the amount of the alcohol added in the previous step (based on the volume). This considers that when a large amount of alcohol is used as the washing component, the purity of DMT in the solid content may increase but the recovery rate may be lowered due to the small amount of DMT dissolved in the alcohol.
  • the recovery rate may be lowered as the washing step is repeated, it may be preferable to suitably adjust the DMT purity in the required solid content.
  • the filtrate obtained through the filtration process can be utilized in the production of MHB. Since the majority of the DMT components in the reaction by-products are separated through the above-mentioned filtration process, Is relatively increased, so that MHB having a higher purity can be produced in a subsequent process.
  • an alcohol may be further added to the filtrate in order to improve efficient stirring and reactivity with the oxime.
  • the alcohol to be added for example, the C 1 to C 10 aliphatic alcohol, Specifically, methanol, ethanol, propanol, isopropanol, butanol, a mixture thereof or water can be used.
  • alcohol may be added and the temperature may be raised to a temperature of about 40 to 70 ° C to dissolve a part of the remaining solid in the filtrate. After the solid content is completely dissolved, the heating may be terminated.
  • the MFB in the filtrate is subjected to oxydation reaction by adding (i) an inorganic acid salt of hydroxyamine or hydroxyamine and (ii) an alkali component to the filtrate (or the filtrate to which the alcohol is added) MHB < / RTI >
  • the inorganic acid salt of hydroxyamine or hydroxyamine used in the oximation reaction may be a hydrochloride, sulfate, nitrate or phosphate of hydroxyamine. More specifically, a 50% aqueous solution of hydroxyamine or a solution of hydroxyamine Hydrochloride or sulfate can be used. It is preferable that the inorganic acid salt of the hydroxyamine or hydroxyamine is used in an amount of at least about 0.5 equivalent, specifically about 1.0 to 2.0 equivalent, based on the MFB in the filtrate. Although the present invention is not limited to the specific amount of the inorganic acid salt of the hydroxyamine or hydroxyamine, when the amount is too small, it may be inefficient due to the low degree of oxigenization reaction. On the other hand, , although the reaction rate is fast, the yield of the target MHB may be lowered due to generation of a side reaction or the like, and therefore, it may be preferable to use it within the above-mentioned range.
  • the oxalization reaction can be carried out under stirring, specifically, an inorganic acid salt of hydroxyamine or hydroxyamine may be added with stirring or simultaneously with stirring. At this time, it is more preferable that the inorganic acid salt of hydroxyamine or hydroxyamine is added in a dropwise addition manner.
  • an oxalization reaction can be performed by adding an alkali component after the addition of the aforementioned inorganic acid salt of hydroxyamine or hydroxyamine.
  • an alkali component may be preferably added in the form of an aqueous solution.
  • the alkali component include NaOH, Ca (OH) 2 , KOH, Na 2 CO 3 , K 2 CO 3 , NaHCO 3 , CH 3 COONa and KNO 3. More specifically, sodium hydroxide .
  • the alkali aqueous solutions listed above are exemplarily described, and the present invention is not necessarily limited thereto.
  • an oxalization reaction can be carried out by adding an alkali component to adjust the pH of the reactant (or reaction liquid) to a range from about 7.0 to about 9.0, specifically from about 7.8 to about 8.2,
  • the pH of the reactant or reaction liquid
  • the pH is too low, there is a problem that the yield is lowered due to the loss of the MHB.
  • the pH is too high, the side reaction is increased, and the present invention is not necessarily limited to the above numerical range.
  • the oxeping reaction can be carried out at a temperature of about 15 to 50 ° C, specifically about 25 to 35 ° C, taking into consideration the reaction rate, the purity of the desired MHB, and the economical efficiency.
  • the reaction product when the oxepitization reaction is terminated, the reaction product may be filtered, washed with water and dried to recover the solid MHB to obtain the desired MHB as a solid. Further, by distilling and concentrating the added alcohol and water, the MHB mixture can be separated into solid components.
  • the amount of water used is preferably in the range of about 2 to about 20 times, more specifically about 3 to 5 times, by weight based on the MFB. If too little water is used, it will affect stirring. If too much water is used, many wastewater will be generated and it will be uneconomical. In addition, the above process may be repeated at least twice as necessary.
  • the present invention it is possible to further include a purification step of washing with an organic solvent to further increase the purity of the target MHB. More specifically, the organic solvent and the solid MHB are added, refluxed, heat-off, and then washed with the organic solvent.
  • the usable cleaning component it may be preferable to use a kind of solvent capable of dissolving and removing the other components while maintaining the maximum MHB content in the solid content.
  • the added organic solvent may be, for example, about 1.5 L per kg of MHB for MHB, and specifically about 3.0 to 5.0 L, and more specifically about 1.0 to 2.0 L.
  • the washing process may be performed once or twice with an organic solvent to further increase the purity of the obtained MHB.
  • the recovery rate may be lowered as the washing process is repeated, it may be preferable to appropriately adjust the purity according to the purity of the MHB in the required solid content.
  • the organic solvent used for the washing may be further recovered.
  • the recovery method may include distillation, for example, May be used.
  • methods known in the art may be adopted for solvent recovery.
  • the purified MHB may be dried at about 80 to about 100 to obtain a solid form, as described above.
  • Conventional drying methods or apparatuses known in the art can be used for this purpose.
  • reaction by-product originating from the DMT production process and containing about 75-79% MFB, about 8.0-12.0% DMT and about 5.0-7.0% MPT was used .
  • the obtained solid content and filtrate were analyzed by HPLC.
  • the DMT, MFB and MPT contents were 92.0%, 7.2% and 0.8%, respectively, and the DMT recovery rate was 92%.
  • the DMT, MFB and MPT contents of the filtrate were 10.6%, 85.5% and 3.9%, respectively.
  • Examples 2 and 3 were the same as those of Example 1 except that only the feed amount of crude MFB, the amount of methanol added, the amount of washing, and the reaction temperature were different. Comparative Example 1 was the same as that of Example 1, and the solvent used in the purification was toluene instead of methanol.
  • Example 2 the purity of DMT in Example 2 is higher than that of Example 3, but the yield is lower.
  • Example 3 where the temperature is relatively lower, the purity of DMT is 91.0% And recovery rate of 95.0% or more is most preferable, but it can be used in consideration of energy efficiency according to lowering of reaction temperature and efficiency of working volume.
  • toluene which is an expensive solvent, is used as a solvent for recovering DMT, which is not suitable as a solvent because of the problem that distillation time and distillation energy cost are large in solvent recovery. 3, the purity and the recovery rate are not remarkably excellent.
  • MFB of 302.1 kg was obtained from the filtrate obtained by recovering DMT in Example 1 above. 80 L of methanol was further added to the filtrate. After the temperature of the filtrate was raised to about 40, the solid was completely dissolved in the filtrate, followed by heat off. Then, 72.0 kg of a hydroxylamine-HCl aqueous solution dissolved in 11 L of water was added dropwise with stirring at 500 rpm for about 6 hours. At this time, half of the amount of the hydroxylamine hydrochloric acid aqueous solution was added dropwise for about 3 hours. When the solid started to be formed, the rest was then added dropwise for about one and a half hours. It was then stirred for 1 hour.
  • Examples 5 to 7 and Comparative Example 2 were carried out in the same manner as in Example 4, except that the amount of c-MFB, the amount of methanol (L) at the purification and the amount of methanol (L) But the addition of 2.0 L, additionally used in Example 7, was carried out using water rather than methanol.
  • Example 5 The yield of Example 5 was lower than that of Example 4, which is because the volume yield was reduced, and Example 4 is more economical than Example 5.
  • Example 7 water, which is not methanol, was added.
  • the yield was lower than that of Example 4 because stirring was not performed smoothly as compared with the case of using methanol.
  • Example 8 The components, content, and yields used in Example 8 and Comparative Example 3 are shown in Table 3 below.
  • Example 8 toluene was used as a solvent for purifying c-MHB.
  • Example 8 The yield and purity of Example 8 was higher than that of Comparative Example 3, and toluene was excellent as a refining solvent.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Chemical Kinetics & Catalysis (AREA)

Abstract

La présente invention a pour objet un procédé de préparation du MHB (4-hydroxyiminobenzoate de méthyle) à partir de sous-produits engendrés dans un procédé de préparation du DMT (téréphtalate de diméthyle). Le procédé comprend les étapes consistant : (a) à ajouter de l'alcool à des sous-produits de réaction contenant du formylbenzoate de méthyle et à filtrer le produit résultant, les sous-produits étant engendrés dans un procédé de préparation du DMT ; (b) à convertir le formylbenzoate de méthyle au sein d'un filtrat en 4-hydroxyiminobenzoate de méthyle par une réaction d'oximation par l'ajout (i) d'hydroxylamine ou de sels d'acide inorganique d'hydroxylamine et (ii) de composants alcalins au filtrat après la filtration ; et (c) à purifier le 4-hydroxyiminobenzoate de méthyle converti.
PCT/KR2011/001051 2010-11-30 2011-02-17 Procédé de préparation du 4-hydroxyiminobenzoate de méthyle Ceased WO2012074168A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR1020100120279A KR101778617B1 (ko) 2010-11-30 2010-11-30 메틸-4-히드록시이미노메틸벤조에이트의 제조방법
KR10-2010-0120279 2010-11-30

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WO2012074168A1 true WO2012074168A1 (fr) 2012-06-07

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005058845A2 (fr) * 2003-12-19 2005-06-30 Novo Nordisk A/S Nouveaux antagonistes/agonistes inverses du glucagon
WO2010062264A1 (fr) * 2008-11-25 2010-06-03 Merlion Pharmaceuticals Pte Ltd Composés de lipopeptides et utilisation de ceux-ci

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005058845A2 (fr) * 2003-12-19 2005-06-30 Novo Nordisk A/S Nouveaux antagonistes/agonistes inverses du glucagon
WO2010062264A1 (fr) * 2008-11-25 2010-06-03 Merlion Pharmaceuticals Pte Ltd Composés de lipopeptides et utilisation de ceux-ci

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
SIMONI, D. ET AL.: "Heterocycle-Containing Retinoids. Discovery of a Novel Isoxazole Arotinoid Possessing Potent Apoptotic Activity in Multidrug and Drug-Induced Apoptosis- Resistant Cells", JOURNAL OF MEDICINAL CHEMISTRY, vol. 44, no. 14, 2001, pages 2308 - 2318 *
SIMONI, D. ET AL.: "Novel Terphenyls and 3,5-Diaryl Isoxazole Derivatives Endowed with Growth Supporting and Antiapoptotic Properties", JOURNAL OF MEDICINAL CHEMISTRY, vol. 51, no. 15, 2008, pages 4796 - 4803 *

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Publication number Publication date
KR101778617B1 (ko) 2017-09-15
KR20120058806A (ko) 2012-06-08

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