WO1996036621A1 - Procede pour recuperer ou recycler des radicaux nitroxydes stables - Google Patents

Procede pour recuperer ou recycler des radicaux nitroxydes stables Download PDF

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Publication number
WO1996036621A1
WO1996036621A1 PCT/NL1996/000201 NL9600201W WO9636621A1 WO 1996036621 A1 WO1996036621 A1 WO 1996036621A1 NL 9600201 W NL9600201 W NL 9600201W WO 9636621 A1 WO9636621 A1 WO 9636621A1
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WO
WIPO (PCT)
Prior art keywords
stable nitroxide
tempo
azeotropic distillation
nitroxide radicals
radicals
Prior art date
Application number
PCT/NL1996/000201
Other languages
English (en)
Inventor
Andre Heeres
Hendrik Arend Van Doren
Ido Pieter Bleeker
Kornelis Fester Gotlieb
Original Assignee
Coöperatieve Verkoop- En Produktievereniging Van Aardappelmeel En Derivaten Avebe B.A.
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
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Application filed by Coöperatieve Verkoop- En Produktievereniging Van Aardappelmeel En Derivaten Avebe B.A. filed Critical Coöperatieve Verkoop- En Produktievereniging Van Aardappelmeel En Derivaten Avebe B.A.
Priority to AU57043/96A priority Critical patent/AU5704396A/en
Publication of WO1996036621A1 publication Critical patent/WO1996036621A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D295/00—Heterocyclic compounds containing polymethylene-imine rings with at least five ring members, 3-azabicyclo [3.2.2] nonane, piperazine, morpholine or thiomorpholine rings, having only hydrogen atoms directly attached to the ring carbon atoms
    • C07D295/22—Heterocyclic compounds containing polymethylene-imine rings with at least five ring members, 3-azabicyclo [3.2.2] nonane, piperazine, morpholine or thiomorpholine rings, having only hydrogen atoms directly attached to the ring carbon atoms with hetero atoms directly attached to ring nitrogen atoms
    • C07D295/24—Oxygen atoms

Definitions

  • This invention relates to a method for substantially quantitatively recovering stable nitroxide radicals, in particular 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO), from a reaction mixture, for the purpose of re-using them, if desired in a continuous process.
  • TEMPO 2,2,6,6-tetramethylpiperidine-N-oxyl
  • Stable nitroxide radicals such as 2,2,6,6-tetramethyl- piperidine-N-oxyl (TEMPO) , 4,4-dimethyloxazolidine-N-oxyl (DOXYL) and 2,2,5,5-tetramethylpyrrolidine-N-oxyl (PROXYL), as well as derivatives thereof, are eminent catalysts for the selective oxidation of hydroxyl group-containing compounds and especially compounds with a primary hydroxyl group. In the presence of these catalysts, primary hydroxyl groups present in compounds are converted, depending on the reaction conditions chosen, into aldehyde functionalities and/or carboxyl groups. Secondary alcohols are oxidized to the corresponding ketones.
  • TEMPO 2,2,6,6-tetramethyl- piperidine-N-oxyl
  • DOXYL 4,4-dimethyloxazolidine-N-oxyl
  • PROXYL 2,2,5,5-tetramethylpyrrolidine-N-oxyl
  • TEMPO particularly TEMPO
  • OTEMPO 4-oxo-2,2,6,6-tetramethyl- piperidine-N-oxyl
  • TEMPOL 4-hydroxy-2,2,6,6-tetra-methylpiperidine-N-oxyl
  • other derivatives with a 2,2,6,6- tetramethylpiperidine-N-oxyl-( EMPO)-skeleton are very suitable for use as catalyst for the selective oxidation of hydroxyl groups.
  • the catalysed reactions occur in the presence of an oxidizing agent, for instance sodium hypochlorite, sodium hypobromite, copper salts or nitric acid.
  • an oxidizing agent for instance sodium hypochlorite, sodium hypobromite, copper salts or nitric acid.
  • a method for the selective oxidation of primary hydroxyl group-containing compounds by the - in situ generated - oxammonium salt of TEMPO is for instance described in R. Siedlecka, J. Skarzewski and J. Mlochowski, Tetrahedron Lett., 21 (1990) 2177-2180.
  • Stable nitroxide radicals such as TEMPO, DOXYL and PROXYL, as well as derivatives thereof, can for instance be used as catalyst in the oxidation of carbohydrates in aqueous suspensions and solutions. During the isolation of the reaction product the catalyst is often lost or the catalyst remains present in the reaction product as an impurity.
  • TEMPO reactive nitroxide radicals
  • DOXYL DOXYL
  • PROXYL aqueous suspensions and solutions
  • German patent application 42.09.869 describes a method for immobilizing 4-hydroxy-TEMPO (TEMPOL; for instance available from Sigma-Aldrich) on polyvinyl -benzyl chloride, whereby likewise an active immobilized catalyst is obtained. Further, the present inventors have found a different method for immobilizing TEMPO on a solid support. This method is represented in DIAGRAM I below. The method starts from the commercially available 4-oxo-TEMPO (OTEMPO; for instance available from Sigma-Aldrich) which through a reductive amination reaction is coupled to silica gel modified with amino groups. The immobilized TEMPO thus obtained in a single-stage process has a catalytic activity in aqueous systems and can, with only a slight decrease in activity, be recovered and re-used. This method can be carried out simply and rapidly.
  • nitroxides such as TEMPO that are immobilized (on solid supports) is less successful in reactions in which the compound to be oxidized is present in suspension or in which a homogeneous catalysis system offers advantages in other respects.
  • the reaction rate is then much lower. If the product of a reaction in the presence of an (immobilized) solid catalyst is water-insoluble, this leads to problems in the separation of the suspended product and the often toxic catalyst immobilized on a solid support.
  • the object of the present ' invention is to provide a method whereby stable nitroxide radicals which are present in non-solid form in a liquid reaction medium can be recovered from reaction mixtures and thereafter can be re ⁇ used.
  • Such a method is suitable both for use during reactions that are carried out in a, preferably aqueous, solution, and for use during reactions that are carried out in a, preferably aqueous, suspension. It has presently been found that stable nitroxide radicals form azeotropes with liquids in which these radicals dissolve. These azeotropes possess substantially a catalytic activity which is of the same order as that of an amount of a solution that contains the same amount of fresh nitroxide radicals.
  • the invention relates to a method for obtaining a catalytically active mixture based on stable nitroxide radicals, in which at least a part of a reaction mixture consisting of a solution or suspension, or a filtrate or supernatant of a suspension, in which stable nitroxide radicals are present in non-solid form, is subjected to an azeotropic distillation.
  • the stable nitroxide radicals are thereby at least partly distilled over with a part of the liquid medium.
  • This radical is prepared by reacting 4-hydroxy-2, 2,6, 6-tetramethylpiperidine with hydrogen peroxide in a medium of aliphatic or cycloaliphatic hydrocarbons, in particular in hexane and cyclohexane. It is stated that by distilling off an azeotrope of hexane or cyclohexane with water, the separation of the intended product is facilitated. The present inventors have reproduced the above and found that in the formation of the azeotrope of hexane or cyclohexane with water, 4-hydroxy- TEMPO does not come over with the azeotrope.
  • 4-hydroxy-TEMPO is illustrated in Examples 1-3 of that European patent application.
  • 4-hydroxy-TEMPO is introduced into the solvent methyl methacrylate.
  • the reaction mixture obtained is heated and an azeotrope is distilled off .
  • the present inventors have not been able to demonstrate any 4-hydroxy-TEMPO in the mixture distilled over. It is further observed that according to EP-A-0 420 790 4-hydroxy-TEMPO is used in amounts that are a factor of 30 lower than the amount of stable nitroxide radical which is preferably used as catalyst according to the present invention.
  • the azeotropic distillation according to the invention can be carried out at different pressures. Preferably, it occurs under reduced pressure, because the loss of stable nitroxide radicals is then less and distillation can be carried out at lower temperatures, which better guarantees the stability of the nitroxide radicals. It is noted that an advantage of distilling at normal pressure is that less solvent needs to be distilled over.
  • the method concerns evaporating at least a part of a solution or suspension, or of a filtrate or supernatant of a suspension, in which a reaction catalysed by stable nitroxide radicals has occurred.
  • the stable nitroxide radical forms an azeotropic mixture with an amount of the reaction medium.
  • the stable nitroxide radical can be quantitatively recovered and reused.
  • the solution or the suspension in which the reaction is carried out which is catalysed by the stable nitroxide radicals preferably contains water.
  • an azeotrope of the nitroxide radical with water is distilled over.
  • the azeotropic distillate obtained according to the invention can be subjected to an extraction.
  • the azeotropic distillation is then followed by an extraction of the obtained solution with a suitable solvent, which is typically organic.
  • a suitable solvent typically organic.
  • the stable nitroxide radical which dissolves in the solvent can subsequently be recovered from this solvent in a known manner.
  • the invention further relates to a method for recirculating stable nitroxide radicals in a continuous process, in which the liquid phase of the product stream (the mixture which contains the reaction products) is subjected to an azeotropic distillation, whereafter the nitroxide radical-containing distillate is returned to the reaction vessel.
  • this method involves the selective oxidation of compounds which contain at least one hydroxyl group, using stable nitroxide radicals as catalyst, in which the liquid phase of the mixture which contains the reaction products is subjected to an azeotropic distillation, whereafter the nitroxide radical-containing distillate is recirculated to the reaction vessel.
  • nitroxide radical-containing distillate is recirculated to the reaction vessel.
  • examples of such compounds to be oxidized are polysaccharides such as starch, cellulose and inulin, as well as derivatives thereof, and lower carbohydrates where the C ⁇ position is protected against oxidation, for instance by the presence of substituents or 1,4-compounds.
  • an oxidizing agent for instance sodium hypochlorite, sodium hypobromite, copper salts or nitric acid.
  • this oxidation reaction is carried out in an aqueous solution or aqueous suspension.
  • a primary hydroxyl group-containing compound is dissolved or suspended in a suitable medium, for instance water.
  • a catalytic amount of stable nitroxide radical preferably TEMPO, has been added.
  • an oxidizing agent is added dropwise or batchwise.
  • the desired pH depends on the oxidizing agent used.
  • the pH is as a rule between about 6 and 13, and preferably between 8 and 10. If as oxidizing agent sodium hypochlorite in the presence of a little sodium bromide is employed, the pH is preferably 9-11.5.
  • the pH is maintained constant by dripping a base or a solution thereof in water, for instance a 1M sodium or potassium hydroxide solution or an aqueous solution of sodium hydrogen carbonate, to the reaction mixture. The reaction has gone to completion if no consumption of base occurs anymore.
  • this can be effected by adding less hypochlorite and/or by quenching the reaction with, for instance, methanol or ethanol.
  • reaction mixture After optional decanting, centrifugation or filtration, is transferred into a vessel, for instance a flask, which is suitable for distillation under reduced pressure.
  • a vessel for instance a flask, which is suitable for distillation under reduced pressure.
  • the flask is placed in a heatable water bath and the pressure is reduced, for instance using a vacuum pump on a rotary evaporator, to the point where water begins to distill over.
  • the system is closed off to prevent loss of material via the vacuum pump.
  • the catalyst in particular TEMPO, is found to be azeotropically distilled over with the first amount of water. Therefore, the catalytically active material can be quantitatively removed from the reaction mixture.
  • the catalyst recovered in this manner dissolved in water or any other azeotrope-forming liquid reaction medium, can be reused. No reduction of the activity of the catalyst arises.
  • the invention further relates to the use of stable nitroxide radicals in the form of a distillate which has been obtained from an azeotropic distillation or an extract from this distillate as catalyst.
  • a compound to be oxidized can be fed to a reaction vessel in a suitable medium with simultaneous discharge of a product stream.
  • the product stream can optionally be subjected to a separation step in which solid substances are separated from the liquid medium. This liquid medium is then distilled, whereby an azeotrope with all catalytic activity therein is formed.
  • This azeotrope can then be returned to the reaction vessel.
  • the invention is presently further illustrated in and by a few non-limiting examples.
  • Other stable nitroxide radicals which form an azeotrope with water or other solvents can also be used.
  • the permanent activity of the recovered catalyst is shown in Table 1.
  • the distilled-over TEMPO containing water fraction was thereupon extracted with 2 x 15 ml diethyl ether.
  • the ether fractions were put together and dried with sodium sulfate. After filtration, the ether was evaporated on a rotary film evaporator.
  • the solution was distilled in a fully closed rotary evaporator under reduced pressure until 20 ml distillate had been collected. In this manner the TEMPO present in the reaction mixture was quantitatively distilled over.
  • the polyglucuronic acid-containing fraction was poured out into 100 ml ethanol, filtered, washed with a 70% ethanol solution and then with acetone and dried in air.

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

Abstract

Cette invention se rapporte à un procédé pour récupérer des radicaux nitroxydes stables, dans lesquels au moins une partie d'un mélange de réaction constitué d'une solution ou d'une suspension, ou un filtrat ou surnageant d'une suspension, où sont présents des radicaux nitroxydes stables sous forme solide, est soumis à une distillatin azéotrope. Cette invention se rapporte en outre à un procédé pour l'oxydation sélective de composés qui contiennent au moins un groupe hydroxyde, en utilisant des radicaux nitroxydes stables comme catalyseur, procédé dans lequel la phase liquide du mélange contenant les produits de réaction est soumise à une distillation azéotrope, puis le distillat contenant les radicaux nitroxydes est recyclé dans la cuve de réaction.
PCT/NL1996/000201 1995-05-18 1996-05-14 Procede pour recuperer ou recycler des radicaux nitroxydes stables WO1996036621A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU57043/96A AU5704396A (en) 1995-05-18 1996-05-14 Method for recovering or recirculating stable nitroxide radi cals

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL1000396 1995-05-18
NL1000396A NL1000396C2 (nl) 1995-05-18 1995-05-18 Werkwijze voor het terugwinnen of recirculeren van stabiele nitroxideradicalen.

Publications (1)

Publication Number Publication Date
WO1996036621A1 true WO1996036621A1 (fr) 1996-11-21

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Application Number Title Priority Date Filing Date
PCT/NL1996/000201 WO1996036621A1 (fr) 1995-05-18 1996-05-14 Procede pour recuperer ou recycler des radicaux nitroxydes stables

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NL (1) NL1000396C2 (fr)
WO (1) WO1996036621A1 (fr)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999023117A1 (fr) * 1997-11-04 1999-05-14 Valtion Teknillinen Tutkimuskeskus Procede de modification de la cellulose
US6379494B1 (en) 1999-03-19 2002-04-30 Weyerhaeuser Company Method of making carboxylated cellulose fibers and products of the method
US6409881B1 (en) 1999-11-08 2002-06-25 Sca Hygiene Products Gmbh Metal-crosslinkable oxidized cellulose-containing fibrous materials and products made therefrom
WO2002059064A1 (fr) * 2001-01-26 2002-08-01 Sca Hygiene Products Ab Procede de recuperation
US6524348B1 (en) 1999-03-19 2003-02-25 Weyerhaeuser Company Method of making carboxylated cellulose fibers and products of the method
US6635755B1 (en) 1999-11-08 2003-10-21 Sca Hygiene Products Gmbh Oxidized polymeric carbohydrates and products made thereof
US6824645B2 (en) 1999-02-24 2004-11-30 Sca Hygiene Products Gmbh Oxidized cellulose-containing fibrous materials and products made therefrom
EP1541565A1 (fr) * 2003-12-08 2005-06-15 SCA Hygiene Products AB Procédé de séparation de composés nitrosonium et/ou hydroxylamine par des résines échangeuses de cations et procédés de récupération et d'oxidation à base de celui-ci
EP1541552A1 (fr) * 2003-12-08 2005-06-15 SCA Hygiene Products AB Procédé de récupération de composés nitroxy à partir de solutions organiques et procédé d'oxydation
EP1541566A1 (fr) * 2003-12-08 2005-06-15 SCA Hygiene Products AB Procédé de séparation de composés nitrosonium et hydroxylamine et son application à l'oxidation des composés hydroxyles
US6919447B2 (en) 2001-06-06 2005-07-19 Weyerhaeuser Company Hypochlorite free method for preparation of stable carboxylated carbohydrate products
US7001483B2 (en) 2003-08-05 2006-02-21 Weyerhaeuser Company Apparatus for making carboxylated pulp fibers
US7517675B2 (en) 2003-12-18 2009-04-14 Cerestar Holding B.V. Oxidation of carbohydrates by means of peroxidases and nitroxy radicals
JP2011116865A (ja) * 2009-12-03 2011-06-16 Dai Ichi Kogyo Seiyaku Co Ltd 酸化多糖類の製法

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1199351A (en) * 1968-03-06 1970-07-22 Bp Chem Int Ltd Improvements in the Preparation of Nitroxides
SU1583415A1 (ru) * 1985-04-16 1990-08-07 Предприятие П/Я А-7253 Способ получени 4-окси-2,2,6,6-тетраметилпиперидин-1-оксила
EP0420790A1 (fr) * 1989-09-25 1991-04-03 The Goodyear Tire & Rubber Company Dérivés d'ester de p-hydroxydiphénylamine

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1199351A (en) * 1968-03-06 1970-07-22 Bp Chem Int Ltd Improvements in the Preparation of Nitroxides
SU1583415A1 (ru) * 1985-04-16 1990-08-07 Предприятие П/Я А-7253 Способ получени 4-окси-2,2,6,6-тетраметилпиперидин-1-оксила
EP0420790A1 (fr) * 1989-09-25 1991-04-03 The Goodyear Tire & Rubber Company Dérivés d'ester de p-hydroxydiphénylamine

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
DATABASE WPI Section Ch Week 9124, Derwent World Patents Index; Class A60, AN 91-176790, XP002008481 *
T. KAWAI ET AL.: "Hydrogenation of Nitroxides on Pt/SiO2", JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, vol. 104, no. 11, WASHINGTON DC US, pages 2951 - 2956, XP002008480 *

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999023117A1 (fr) * 1997-11-04 1999-05-14 Valtion Teknillinen Tutkimuskeskus Procede de modification de la cellulose
US6824645B2 (en) 1999-02-24 2004-11-30 Sca Hygiene Products Gmbh Oxidized cellulose-containing fibrous materials and products made therefrom
US6379494B1 (en) 1999-03-19 2002-04-30 Weyerhaeuser Company Method of making carboxylated cellulose fibers and products of the method
US6524348B1 (en) 1999-03-19 2003-02-25 Weyerhaeuser Company Method of making carboxylated cellulose fibers and products of the method
US6409881B1 (en) 1999-11-08 2002-06-25 Sca Hygiene Products Gmbh Metal-crosslinkable oxidized cellulose-containing fibrous materials and products made therefrom
US6635755B1 (en) 1999-11-08 2003-10-21 Sca Hygiene Products Gmbh Oxidized polymeric carbohydrates and products made thereof
US6987181B2 (en) 1999-11-08 2006-01-17 Sca Hygiene Products Gmbh Oxidized polymeric carbohydrates and products made thereof
WO2002059064A1 (fr) * 2001-01-26 2002-08-01 Sca Hygiene Products Ab Procede de recuperation
US6919447B2 (en) 2001-06-06 2005-07-19 Weyerhaeuser Company Hypochlorite free method for preparation of stable carboxylated carbohydrate products
US7135557B2 (en) 2001-06-06 2006-11-14 Weyerhaeuser Company Hypochlorite free method for preparation of stable carboxylated carbohydrate products
US7109325B2 (en) 2001-06-06 2006-09-19 Weyerhaeuser Company Hypochlorite free method for preparation of stable carboxylated carbohydrate products
US7001483B2 (en) 2003-08-05 2006-02-21 Weyerhaeuser Company Apparatus for making carboxylated pulp fibers
WO2005058850A1 (fr) * 2003-12-08 2005-06-30 Sca Hygiene Products Ab Procede de separation de composes hydroxylamine et nitrosonium et son utilisation pour l'oxydation de composes hydroxy
WO2005058851A1 (fr) * 2003-12-08 2005-06-30 Sca Hygiene Products Ab Procede permettant la separation de nitrosonium organique et/ou de composes hydroxylamine au moyen de resines echangeuses de cations, et procedes d'extraction et d'oxydation derives de ce procede
WO2005058818A1 (fr) * 2003-12-08 2005-06-30 Sca Hygiene Products Ab Procede de recuperation de composes nitroxy a partir de solutions organiques et procede d'oxydation
EP1541566A1 (fr) * 2003-12-08 2005-06-15 SCA Hygiene Products AB Procédé de séparation de composés nitrosonium et hydroxylamine et son application à l'oxidation des composés hydroxyles
EP1541552A1 (fr) * 2003-12-08 2005-06-15 SCA Hygiene Products AB Procédé de récupération de composés nitroxy à partir de solutions organiques et procédé d'oxydation
EP1541565A1 (fr) * 2003-12-08 2005-06-15 SCA Hygiene Products AB Procédé de séparation de composés nitrosonium et/ou hydroxylamine par des résines échangeuses de cations et procédés de récupération et d'oxidation à base de celui-ci
US7517675B2 (en) 2003-12-18 2009-04-14 Cerestar Holding B.V. Oxidation of carbohydrates by means of peroxidases and nitroxy radicals
JP2011116865A (ja) * 2009-12-03 2011-06-16 Dai Ichi Kogyo Seiyaku Co Ltd 酸化多糖類の製法

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Publication number Publication date
AU5704396A (en) 1996-11-29
NL1000396C2 (nl) 1996-11-19

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