WO2002010097A1 - Procede de separation de composes de benzene a substitution o et p - Google Patents

Procede de separation de composes de benzene a substitution o et p Download PDF

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Publication number
WO2002010097A1
WO2002010097A1 PCT/IN2000/000072 IN0000072W WO0210097A1 WO 2002010097 A1 WO2002010097 A1 WO 2002010097A1 IN 0000072 W IN0000072 W IN 0000072W WO 0210097 A1 WO0210097 A1 WO 0210097A1
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WO
WIPO (PCT)
Prior art keywords
ion exchange
exchange resin
anyone
compound
formula
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PCT/IN2000/000072
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English (en)
Inventor
Vilas Gajanan Gaikar
Hyacinth Mary Anasthas
Original Assignee
Department Of Science & Technology (Dst)
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Filing date
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Application filed by Department Of Science & Technology (Dst) filed Critical Department Of Science & Technology (Dst)
Priority to AU2001210522A priority Critical patent/AU2001210522A1/en
Priority to CNB008134111A priority patent/CN1183062C/zh
Priority to PCT/IN2000/000072 priority patent/WO2002010097A1/fr
Publication of WO2002010097A1 publication Critical patent/WO2002010097A1/fr

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C209/00—Preparation of compounds containing amino groups bound to a carbon skeleton
    • C07C209/54—Preparation of compounds containing amino groups bound to a carbon skeleton by rearrangement reactions
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07B—GENERAL METHODS OF ORGANIC CHEMISTRY; APPARATUS THEREFOR
    • C07B63/00—Purification; Separation; Stabilisation; Use of additives
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/78—Separation; Purification; Stabilisation; Use of additives
    • C07C45/79—Separation; Purification; Stabilisation; Use of additives by solid-liquid treatment; by chemisorption
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/78—Separation; Purification; Stabilisation; Use of additives
    • C07C45/80—Separation; Purification; Stabilisation; Use of additives by liquid-liquid treatment
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/42—Separation; Purification; Stabilisation; Use of additives
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/42—Separation; Purification; Stabilisation; Use of additives
    • C07C51/47—Separation; Purification; Stabilisation; Use of additives by solid-liquid treatment; by chemisorption
    • C—CHEMISTRY; METALLURGY
    • C40—COMBINATORIAL TECHNOLOGY
    • C40B—COMBINATORIAL CHEMISTRY; LIBRARIES, e.g. CHEMICAL LIBRARIES
    • C40B40/00—Libraries per se, e.g. arrays, mixtures

Definitions

  • the present invention relates to a process for producing o- and p- substituted benzene compounds separately from a binary mixture in any proportions of said compounds.
  • isomeric and non-isomeric close boiling mixtures are often an industrial problem.
  • methods of resolving isomeric mixtures such as mixtures of substituted phenols e.g., hydroxyacetophenones; and substituted anilines and substituted benzoic acids.
  • the separation of isomeric mixtures is important in chemical process industries.
  • the separation of such substances by physical methods like distillation, crystallization, solvent extraction, etc. is either difficult or economically not viable.
  • HAP o- and p-hydroxyacetophenones
  • the composition of the product varies from 10% to 95% of o-HAP depending upon the conditions of the reaction and the catalyst, p- Hydroxyacetophenone (p-HAP) is a solid white crystalline powder with a boiling point of 148°C/3mm of Hg.
  • p-HAP Hydroxyacetophenone
  • o-Hydroxyacetophenone o-HAP
  • o-HAP is a greenish-yellow liquid at room temperature with a boiling point of 213°C/717mm of Hg.
  • p-HAP is used for the manufacture of Bufexamac (4-Butoxy-N-hydroxybenzeneacetamide) which is used as an anti-inflammatory, analgesic and antipyretic agent. It is also used in the manufacture of Pixifenide (l-l[4-[l(Hydroxyimino)ethyl]phenoxy] acetyljpipehdine) which is used as an anti-inflammatory agent.
  • o-HAP is used for the manufacture of 4-hydroxycoumarin which is the basic raw material for the manufacture of Acenocoumarol [3-(a-acetonyl-p-nitroben ⁇ yl)-4-hydroxycou ⁇ narin] used as an anticoagulant and vitamin K antagonist, Tioclomarol (3-[3-(4-chloro ⁇ henyl)-l-(5- chloro-2-thienyl)-3-hydroxypropyl)-4-hydroxy-2H-l-ben ⁇ opyran-2-one) used as an anticoagulant and Warfarin Sodium (3-(a -acetonylbenzyl)-4-hydroxycoumarin sodium salt) also used as an anticoagulant.
  • Another object of the present invention is to provide process for producing said pure compounds of Formula 1 and Formula 2 separately in high yield from said mix of said compounds of Formula 1 and 2.
  • Yet further object is directed to provide a process for producing said pure compounds of Formula 1 and Formula 2 separately from mix of said compounds of Formula 1 and 2 which would be simple and cost effective to carry out.
  • the said step of treating said binary mixture with said organic solvent in step (i) comprise further washing said undissolved compound separated with fresh solvent to thereby obtain an additional solution phase containing the soluble compound and a further amount of the substantially pure undissolved compound which is seperated ; and said step of contacting said solution phase with said ion exchange resin, comprise contacting the said solution phase and the said additional solution phase together with said ion exchange resin.
  • the adsorbed components of Formula 1 and 2 from said ion exchange resin subsequent to said ion exchange treatment are recovered following : a) treating the said adsorbent ion exchange resin of step (ii) with anyone of an organic polar solvent, aqueous alkali and acid solvent to thereby desorb said compounds of formula 1 and 2 from said resin ; b) recovering the said compound of formula 1 and 2 by desolventising the solution obtained in step (a) above in conventional way and adding back the thus recovered mix of said compounds of Formula 1 and 2 as said binary mix in said step (i) above. Also to favour economizing the process of the invention the ion exchange resin s regenerated and the solvents recycled in the above process.
  • the term 'isomeric mixtures' as used herein include mixtures of disubstituted benzenes with the substituent group occupying different positions on the benzene group.
  • the major substituent is generally hydroxyl group (-OH) forming substituted phenols and amino group (NH 2 ) forming substituted anilines.
  • the second substituent group is nitro, chloro, methoxy, ethoxy, hydroxy etc.
  • the term 'preferential solubilization' implies significantly higher solubility of one of the components (o-isomer) in the organic solvent as compared to the other component (p-isomer).
  • the p-isomer will also be soluble in the organic solvent due to the presence of the o-isomer. But such solubilization will not adversely affect the separation process as long as the ratio of the solubilized amount of the o-isomer to that of the p-isomer is extremely high.
  • the selection of the solvent for the first step has to be done based on the solubility data and other properties such as the boiling point, toxic-ty, etc.
  • the solvent selected should be such in which the solubility of one component is extremely high while that of the other component is comparatively low. Also, the solvent should not dissolve the ion-exchange resin selected for the adsorption in step ⁇ iii).
  • Organic solvent employed in step (i) is selected from a group of aliphatic, alicyclic, aromatic hydrocarbons, their chlorinated derivatives; ethers; esters; amides and ketones and combinations thereof.
  • n-heptane, cyclohexane, toluene are useful for selective / preferential solubilisation of these compounds, n- Aliphatic hydrocarbons are preferred solvents.
  • Ion exchange resin used in step (iii) is selected from group consisting of polymeric structures with styrene - divinylbenzene as polymeric backbone with primary, secondary or tertiary amine or quaternary ammonium group for acidic mixtures, and sulphonic acid or carboxylic acid as functional group for mixtures of amines;
  • ion exchange resins useful in this process are Indion 850, Indion 810, Indion 925, Tulsion A-2X MP, Dowex MSA-1, (These are trade names under which ion exchange resins are available).
  • the term 'preferential adsorption' implies significantly higher adsorption of one of the components on the ion-exchange resin as compared to that of the other component in the mixture. It is recognized that the second component from the extract phase can also adsorb on the same i ⁇ n-exchange resin, in lesser quantities than the predominantly adsorbed component. Such adsorption is not deleterious to resolution if the ratio of the adsorbed amount of the preferentially adsorbed component to adsorbed amount of other component is high.
  • the nature and amount of these amino and acidic groups and the presence of aromatic rings in the polymeric structure of the resins are believed to be significant for the adsorption on these ion-exchange resins.
  • the process of invention is particularly suited for the separation of isomeric mixtures of organic acids and bases. Examples of such mixtures include o-/p-hydroxyacetophenones, o-/p-nitroanilines, o-/p- chloroanilines, o-/p-nitrophenols, o-/p-chlorophenols, o-/p-hydroxybenzoic acids, o-/p- hydroxybenzaldehydes, o-/p-aminoacetophenones, etc.
  • the o-isomer is selectively solubilized in an organic solvent.
  • the p- isomer is preferentially adsorbed.
  • Organic polar solvent employed in step (v) is selected from group consisting of aliphatic alcohols, alicyclic alcohols, aromatic alcohols, esters, ethers, ketones, amides and aqueous alcohols, acids, alkalies and combinations thereof.
  • aliphatic alcohols aliphatic alcohols
  • alicyclic alcohols aromatic alcohols
  • esters ethers
  • ketones amides
  • aqueous alcohols acids, alkalies and combinations thereof.
  • Methanol, ethanol, acetone are the preferred solvents.
  • a mixture of the isomers is brought in contact with the selected organic solvent and agitated for a period sufficient for the solubilization to take place.
  • the amount of the solvent utilized is calculated from the solubility of the more soluble isomer.
  • a sufficient time for solubilization is usually 30 minutes.
  • the agitation is conducted at selected temperature and atmospheric pressure. After agitation, the precipitated component is separated from the organic solution by filtration or by decantation.
  • the organic phase containing almost all o-isomer and small quantities of the dissolved p- isomer in the organic solvent is brought into contact with the ion exchange resin (IER) in the form of a slurry or it can be passed through a column packed with the ion exchange resin.
  • IER ion exchange resin
  • the slurry is agitated for a period sufficient for the adsorption to take place.
  • a typical adsorption time is in the range of 15 min to 2 hrs.
  • the mixing is conducted at selected temperature and atmospheric pressure.
  • the ion-exchange resin is separated from the liquid by decantation or filtration or centrifugation.
  • the separated ion-exchange resin is treated either with polar solvent, such as methanol or with aqueous alkali solution to release the adsorbed organic compounds. This release can be conducted at selected temperature.
  • the ion exchange resin is recovered, dried and recycled for subsequent separation.
  • the organic compounds liberated from the ion-exchange resin by polar solvent is recovered by fractional distillation. If an aqueous alkali solution is used for liberation of adsorbed phenolic compounds, then the solution is first treated with aqueous mineral acid to neutralize the base and the organic compound is separated as a second phase. This organic compound can be separated by decantation or filtration or centrifugation.
  • the ion exchange resins are packed in a column, with a provision of influent and effluent streams of mixtures, and the orgamc phase containing almost all o-isomer and small quantities of the dissolved p-isomer in the organic solvent is pumped through the ion exchange resin bed at a specified flow rate wherein preferential adsorption of p-HAP takes place.
  • the effluent from the column is thus pure o-HAP.
  • the effluent from the column is collected till the concentration of p-HAP starts increasing in the effluent. After this concentration, the flow of the mixture solution is stopped and the column is drained of any residual liquid.
  • a flow of alcohol is started through the column in the same direction as the mixture solution or in the opposite direction.
  • the solution at the effluent is collected until the effluent concentration of the hydroxyacetophenones drops to zero.
  • the column is then drained of the solution, dried and used for next cycle of adsorption.
  • the column was drained of residual fluid and aqueous alkaline solution is passed through the column until concentration of HAP's in effluent drops to zero. The column is then drained of solution, washed with methanol, dried and used for next cycle of adsorption.
  • the major advantage of this method is that the mixture of o- and p-isomers can be separated into pure o- and p-isomers in single equilibrium stage operations by adopting this two step strategy.
  • the process of invention is particularly suited for the separation of isomeric mixtures of organic acids and bases. Isomeric mixtures susceptible to treatment with the process of invention include o- and p-substituted compounds.
  • Such mixtures include o-/p-hydroxyacetophenones, o- /p-nitroanilines, o-/p-chloroanilines, o-/p-nitrophenols, o-/p-chlorophenols, o-/p- hydroxybenzoic acids, o-/p-hydroxybenzaldehydes, o-/p-aminoacetophenones, etc.
  • Ion exchange resin Indion 850 (Ion Exchange India, Ltd.) Methanol (AR grade)
  • a reaction vessel (200ml) equipped with a stirrer was charged with a mixture containing 2.68 gms of o-HAP and 0.22 gms of p-HAP. To this mixture, 50ml of n- heptane was added. This mixture was stirred for a period of 30 minutes at room temperature of 303K. The mixture was filtered to separate the precipitated p-HAP from the orgamc phase and then washed with pure heptane to give 0.176 gms (80% recovery) in pure form (100% purity).
  • the mixture contained 3.6gms of o-HAP and 0.34gms of p-HAP.
  • the extract phase contained 0.067gms of p-HAP and 3.5gms of o-HAP After adsorption, the residual solution contained 3.48gms by weight of o-HAP (96.67% recovery) without any trace of p-HAP.
  • Example 3 Example 3:
  • a reaction vessel equipped with a stirring means was charged with 23 ml of solution containing 0.61 gms of o-HAP and 0.62 gms of p-HAP in dichloromethane.
  • 2.0 gms of dried ion exchange resin, Indion 850 was added to form a slurry.
  • the adsorption was conducted by stirring this mixture for 8 hours at 303K.
  • the mixture was filtered under suction so as to separate the ion exchange resin from the liquid solution.
  • the separated ion exchange resin was washed with dichloromethane.
  • the filtrate contain 0.21 gms of p-HAP and 0.58 gms of o-HAP (as determined by high performance liquid chromatography).
  • a reaction vessel (200ml) equipped with a stirrer was charged with a mixture containing 35 gms of o-HAP and 1.75 gms of p-HAP. To this mixture, 500ml of n- heptane was added. This mixture was stirred for a period of 30 minutes at room temperature of 303K. The mixture was filtered to separate the precipitated p-HAP from the organic phase and then washed with pure heptane (55ml) to give 1.567 gms (89.5% recovery) in pure form (100% purity).
  • the extract solution phase contained 0.183 gms of p-HAP and 35 gms of o-HAP as determined by HPLC.
  • the extract solution phase was then pumped through a column (2.0 cm diameter and 37 cm height) filled with the ion exchange resin, Indion 850.
  • the ion exchange resin Indion 850.
  • the recovery of o-HAP in the extract solution was 78.5% (100% purity).
  • Ion exchange resin Indion 850, weak base resin (Ion Exchange India, Ltd.) : Indion 810 strong base resin (Ion Exchange India, Ltd.)
  • Example 5 Ion exchange resin : Indion 850, weak base resin (Ion Exchange India, Ltd.) : Indion 810 strong base resin (Ion Exchange India, Ltd.)
  • a reaction vessel (200 ml) equipped with a stirrer was charged with a mixture containing 0.48 gms of o-NP and 0.4 gms of p-NP. To this mixture, 50 ml of n-heptane was added. This mixture was stirred for a period of 30 minutes at room temperature of 303 K. The mixture was filtered to separate the precipitated p-NP from the organic phase and then washed with pure heptane to give 0.3995 gms (99.88% recovery) in pure form (100% purity).
  • the example was the same as Example 5 except that the quantities of NP's and the resin used were different.
  • the mixture contained 5 gms of o-NP and 5 gms of p-NP.
  • the extract phase contained 0.006 gms of p-NP and 4.7 gms of o-NP.
  • the residual solution contained 4.55 gms by weight of o- NP (96.8% recovery) without any trace of p-NP.
  • a reaction vessel equipped with a stirring means was charged with 10 ml of solution containing 0.12 gms (0.93% w/w) of p-PDA and 0.1 gms (0.8% w/w) of o- PDA and 9.8 ml of 1,2-dichloroethane as a solvent for the phenylenediamines.
  • 0.1 gms of dried ion exchange resin (Indion 840) was added to form a slurry like mixture. The adsorption was run by stirring this mixture for 8 hours at room temperature. The mixture as filtered under suction so as to separate the ion exchange resin from the liquid solution.
  • the filtrate contain 0.042% (w/w) of p-PDA and 0.69% (w/w) of o-PDA as determined by GC using SE-30 column (Perkin Elmer model).
  • Example 8 Example 8 :
  • the example was the same as example 7 except thatthe quantities of PDA's used were different.
  • the mixture contained 0.23 gms (1.8% w/w) of o-PDA and 0.21 gms (1.66% w/w) of p-PDA. After adsorption, the filtrate contain 0.718% (w/w) of p- PDA and 1.64% (w/w) of o-PDA as determined by GC.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

La présente invention concerne un procédé de production de composés de benzène à substitution o et p séparément à partir d'un composé binaire suivant n'importe quelle proportion desdits composés. Les composés de benzène à substitution o ou p comprennent respectivement un composé de benzène 1, 2 substitué isomère de formule (1) et un composé de benzène 1,4 substitué de formule (2). Dans les formules, R1 est sélectionné dans le groupe formé par -OH, -COOH, -NH2, N(R3)(R4) où R3 et R4 proviennent du groupe -H, (CH2)nCH3; n est compris entre 0 et 4; et R2 est sélectionné dans le groupe formé par -(CO-CH3), -(NH2), -(OH), -(NO2), -(X), -(OCH3), -COOH, -CHO, -(OCH2CH3) et X représente halogène sélectionné parmi F, CL, Br et I. Le procédé comprend, de manière fondamentale, (i) le traitement du mélange binaire tout d'abord avec un solvant organique pour séparer par phase au moyen d'une solubilisation préférentielle un desdits composés, (ii) la mise en contact de la phase solution avec une résine échangeuse d'ions pour adsorber et récupérer de manière préférentielle un des composés non dissous présents pour effectuer ensuite la séparation par phase du composé présent dans ladite phase solution, de l'autre composé sous forme de composé non dissous sensiblement pur, et (iii) la récupération dans ladite phase solution de l'étape (ii) au-dessus dudit composé soluble sous forme sensiblement pure au moyen de la désolvantisation de la phase solution de manière classique. Ce processus constitue un procédé simple et peu coûteux de production de composés purs de formules (1) et (2) séparément et avec un rendement élevé.
PCT/IN2000/000072 2000-07-27 2000-07-27 Procede de separation de composes de benzene a substitution o et p WO2002010097A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
AU2001210522A AU2001210522A1 (en) 2000-07-27 2000-07-27 A process for separating o- and p-substituted benzene compounds
CNB008134111A CN1183062C (zh) 2000-07-27 2000-07-27 分离邻-和对-取代苯化合物的方法
PCT/IN2000/000072 WO2002010097A1 (fr) 2000-07-27 2000-07-27 Procede de separation de composes de benzene a substitution o et p

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/IN2000/000072 WO2002010097A1 (fr) 2000-07-27 2000-07-27 Procede de separation de composes de benzene a substitution o et p

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Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100369883C (zh) * 2006-06-28 2008-02-20 乔旭 邻氯苯甲酸和对氯苯甲酸混合物的分离方法
CN106554264A (zh) * 2016-11-07 2017-04-05 北京天弘天达医药科技有限公司 一种对羟基苯乙酮产品及其制备方法与用途

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2838570A (en) * 1954-03-26 1958-06-10 Byk Gulden Lomberg Chem Fab Process of producing pure halogeno methyl (p-hydroxy phenyl) ketones
US3894096A (en) * 1971-12-07 1975-07-08 American Cyanamid Co Separation of para-nitrated phenolic compounds from crude reaction mixtures containing ortho-and para-nitrated phenolic compounds
EP0487818A1 (fr) * 1990-11-27 1992-06-03 Director-General Of The Agency Of Industrial Science And Technology Procédé pour la séparation d'isomères de benzènes disubstitués et agents pour y être utilisés
WO1994014746A1 (fr) * 1992-12-23 1994-07-07 Technische Universiteit Delft Procede de separation des ortho- et para-isomeres d'acide hydroxymandelique ou de son sel, isomeres ainsi obtenus, et utilisation de l'ortho-isomere dans la preparation de eddha

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2838570A (en) * 1954-03-26 1958-06-10 Byk Gulden Lomberg Chem Fab Process of producing pure halogeno methyl (p-hydroxy phenyl) ketones
US3894096A (en) * 1971-12-07 1975-07-08 American Cyanamid Co Separation of para-nitrated phenolic compounds from crude reaction mixtures containing ortho-and para-nitrated phenolic compounds
EP0487818A1 (fr) * 1990-11-27 1992-06-03 Director-General Of The Agency Of Industrial Science And Technology Procédé pour la séparation d'isomères de benzènes disubstitués et agents pour y être utilisés
WO1994014746A1 (fr) * 1992-12-23 1994-07-07 Technische Universiteit Delft Procede de separation des ortho- et para-isomeres d'acide hydroxymandelique ou de son sel, isomeres ainsi obtenus, et utilisation de l'ortho-isomere dans la preparation de eddha

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CN1183062C (zh) 2005-01-05
AU2001210522A1 (en) 2002-02-13
CN1376140A (zh) 2002-10-23

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