JP2002320861A - Method for separating metal catalyst - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method to separate imide compounds and a metal catalyst from a mixture containing the imide compounds and the metal catalyst. SOLUTION: The imide compounds and the metal catalyst are separated from a mixture composed of the imide compounds (N-acetoxyphthalimide, N- hydroxyphthalimide or the like) and the metal catalyst (water-soluble promoter or the like) by using a specified aqueous solvent (e.g. water) and a nonaqueous soluble solvent (alcohols, nitriles, hydrocarbons or a mixture solvent of these).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a mixture containing a specific imide compound and a metal catalyst by using an aqueous solvent.
The present invention relates to a method useful for efficiently separating an imide compound and a metal catalyst.

[0002]

2. Description of the Related Art When an imide compound such as N-hydroxyphthalimide is used, a substrate can be efficiently oxidized by contact with oxygen. For example, JP-A-8-38909, JP-A-9-327626 and JP-A-9-2
No. 78675 discloses that an imide compound such as N-hydroxyphthalimide is used as an oxidation catalyst, and a substrate (hydrocarbons, for example, a methyl group-containing aromatic hydrocarbon such as cyclohexane or xylene, a diene or the like) is converted to a molecular compound. A method of oxidizing by contact with oxygen is disclosed.

Further, the imide compound is useful as a catalyst in various reactions such as a nitration reaction.
For example, JP-A-11-239730 discloses a method of reacting a substrate with nitrogen oxide in the presence of the imide compound to obtain a corresponding nitro compound, and reacting the substrate with carbon monoxide and oxygen. And methods for producing the corresponding carboxylic acids. WO 99/41219 discloses that in the presence of the imide compound, the substrate is oxygen and 1,2
It is disclosed that an acylation reaction proceeds when reacted with a dicarbonyl compound (such as biacetyl). According to the proceedings of the 1999 Annual Meeting of the Chemical Society of Japan, when an α, β-unsaturated ester is reacted with an alcohol and oxygen using N-hydroxyphthalimide as a catalyst, a radical coupling reaction proceeds, and α-hydroxy-γ -It is reported that butyrolactone is formed, and that when hydrocarbons are reacted with oxygen and sulfur dioxide, the corresponding sulfonic acid is formed.

[0004] A method for separating an oxidation reaction product from an oxidation catalyst has also been proposed. For example, JP-A-10-11
No. 4702 discloses that a target product (such as adipic acid) is obtained by oxidizing a substrate (such as cyclohexane) in the presence of the oxidation catalyst (imide compound) using an aqueous solvent and a water-insoluble solvent from the reaction mixture. And a method for separating the oxidation catalyst from the oxidation catalyst. This method is useful for separating a water-soluble reaction product from a water-insoluble oxidation catalyst. However, it is difficult to separate the water-insoluble reaction product from the water-insoluble oxidation catalyst and to separate the water-insoluble reaction product from the water-soluble oxidation catalyst. Further, in the above method, it may be difficult to separate a water-soluble product from an aqueous phase depending on the type of an oxidation reaction product. In particular, when the reaction is carried out in the presence of a metal catalyst to promote the reaction, it is difficult to efficiently separate the oxidation catalyst and the metal catalyst in addition to separating the reaction product. Therefore, it is also difficult to separate and recover the metal catalyst and reuse it.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for efficiently separating an imide compound and a metal catalyst.

Another object of the present invention is to provide a separation method capable of efficiently separating and recovering an imide compound and a metal catalyst from a reaction mixture by a simple operation.

[0007]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, in a method of contacting a substrate with oxygen in the presence of an imide compound and a metal catalyst, an aqueous solvent and a non-aqueous solvent are used. By using a water-soluble solvent, the inventors have found that the imide compound and the metal catalyst can be efficiently separated, and completed the present invention.

That is, in the method of the present invention, a mixture containing an imide compound having an imide unit represented by the following formula (I) and a metal catalyst is separated from an aqueous solvent containing at least water and the aqueous solvent. The imide compound is distributed to the non-water-soluble solvent layer and the metal catalyst is distributed to the aqueous solvent layer using a liquid-soluble non-water-soluble solvent.

[0009]

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Wherein X represents an oxygen atom, a hydroxyl group or an acyloxy group. The aqueous solvent may be water. The water-insoluble solvent may be a hydrocarbon, an alcohol, a nitrile, a mixed solvent thereof or the like. The imide compound may be an aromatic imide compound, the metal catalyst is a water-soluble compound,
Further, it may be a transition metal compound and a compound containing a Group 13 element of the periodic table. Examples of the water-insoluble solvent include hydrocarbons having 6 or more carbon atoms, alcohols having 4 or more carbon atoms, aromatic nitriles, and mixed solvents thereof such as alcohols, mixed solvents of hydrocarbons and alcohols, and carbonized solvents. It may be a mixed solvent of hydrogens and nitriles.

[0011] The present invention also relates to a method for preparing a catalyst comprising an imide compound and a metal catalyst in the presence of a catalyst system comprising the imide compound and a metal catalyst by using a solvent from a reaction mixture formed by contacting a substrate with oxygen. There is also included a method of separating a reaction product by distributing a catalyst to a solvent phase and separating an imide compound and a metal catalyst from the solvent phase. The reaction may be carried out in the presence of a solvent, and the reaction mixture may be concentrated prior to crystallization of the reaction product. The reaction product may be an aromatic carboxylic acid, the imide compound may be an aromatic compound, and the metal catalyst may be a compound soluble in an aqueous solvent. Further, the solvent for separating the reaction product may be an organic solvent which may contain water (for example, C _1-4 alkanecarboxylic acid, C _1-10 alkyl alcohol, etc.).

In the present specification, the term “imide compound” and “metal catalyst” distributed in the solvent phase are not limited to active imide compounds and metal catalysts, but also include products with reduced activity, altered or decomposed products. Is also used to include the meaning. In addition, “crystallization” includes rinsing or repulping in which the target compound is washed or crystallized using a relatively small amount of solvent.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [Imide compound] An imide compound has an imide unit represented by the following formula (I).

[0014]

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(Wherein X represents an oxygen atom, a hydroxyl group or an acyloxy group) Examples of the acyloxy group include acyloxy groups having about 1 to 6 carbon atoms such as formyloxy, acetyloxy (acetoxy), propionyloxy and butyryloxy. Groups (preferably C _1-4 acyloxy groups, especially acetyloxy groups).

Specific examples of the imide compound include, for example,
The compound represented by the following formula (II) can be exemplified.

[0017]

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(Wherein R ¹ and R ² are the same or different and are each a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a cycloalkyl group, a hydroxyl group, an alkoxy group, a carboxyl group, an alkoxycarbonyl group, an acyl group R ¹ and R ² may be bonded to each other to form a double bond or an aromatic or non-aromatic ring;
^The aromatic or non-aromatic ring formed by ¹ and R ² has at least one imide unit represented by the formula (I).
You may have one. X is the same as described above.) In the compound of the formula (II), the halogen atom among the substituents R ¹ and R ² includes iodine, bromine, chlorine and fluorine. Examples of the alkyl group include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-
Butyl, t-butyl, pentyl, hexyl, heptyl,
Octyl, straight-chain or branched-chain alkyl group (preferably C _1-6 alkyl groups, especially C _{1 -4} alkyl group) having about 1 to 10 carbon atoms such as decyl groups include.

The aryl group includes a phenyl group, a naphthyl group and the like, and the cycloalkyl group includes a C _3-10 cycloalkyl group such as a cyclopentyl, cyclohexyl and cyclooctyl group. Examples of the alkoxy group include an alkoxy group having about 1 to 10 carbon atoms such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, t-butoxy, pentyloxy, and hexyloxy, preferably a C _1-6 alkoxy group. , Especially C
_1-4 alkoxy groups are included.

The alkoxycarbonyl group includes, for example, carbon atoms of an alkoxy moiety such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl, t-butoxycarbonyl, pentyloxycarbonyl and hexyloxycarbonyl. About 1 to 10 alkoxycarbonyl groups (preferably C _1-6 alkoxy-carbonyl group, more preferably C _1-4 alkoxy-
Carbonyl group).

Examples of the acyl group include those having 1 to 6 carbon atoms such as formyl, acetyl, propionyl, butyryl, isobutyryl, valeryl, isovaleryl and pivaloyl groups.
A certain number of acyl groups can be exemplified.

The substituents R ¹ and R ² may be the same or different. In the above formula (II), R ¹ and R ²
May be bonded to each other to form a double bond or an aromatic or non-aromatic ring. The preferred aromatic or non-aromatic ring is a 5- to 12-membered ring, particularly a 6- to 10-membered ring, and may be a heterocyclic ring or a fused heterocyclic ring, but is often a hydrocarbon ring. An aromatic or non-aromatic ring is
It may have at least one (usually 1 or 2) imide units represented by the formula (I). Such a ring includes, for example, a non-aromatic alicyclic ring [a cycloalkane ring optionally having a substituent (such as a cyclohexane ring), a cycloalkene ring optionally having a substituent (eg, cyclohexene ring). A non-aromatic bridged ring (eg, a bridged hydrocarbon ring which may have a substituent (eg, a 5-norbornene ring)), an aromatic group which may have a substituent Ring (benzene ring, naphthalene ring, etc.). The ring is often composed of an aromatic ring.

Preferred imide compounds include those represented by the following formula:

[0024]

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Wherein R ^{3 to} R ⁶ are the same or different,
A hydrogen atom, an alkyl group, a hydroxyl group, an alkoxy group, a carboxyl group, an alkoxycarbonyl group, an acyl group, a nitro group, a cyano group, an amino group, and a halogen atom are shown. R ¹ , R ² and X are the same as described above) In the substituents R ^{3 to} R ⁶ , the same groups or atoms as described above can be exemplified as the alkyl group, alkoxy group, alkoxycarbonyl group, acyl group and halogen atom. The substituents R ^{3 to} R ⁶ are usually a hydrogen atom, a lower alkyl group having about 1 to 4 carbon atoms, a carboxyl group, a nitro group, or a halogen atom in many cases.

The imide compounds can be used alone or in combination of two or more.

The acid anhydride corresponding to the imide compound represented by the formula (I) includes, for example, a saturated or unsaturated aliphatic dicarboxylic anhydride such as succinic anhydride and maleic anhydride, and tetrahydrophthalic anhydride. Saturated or unsaturated non-aromatic cyclic polyvalent such as acid, hexahydrophthalic anhydride (1,2-cyclohexanedicarboxylic anhydride), 1,2,3,4-cyclohexanetetracarboxylic acid, 1,2-anhydride Bridged cyclic polycarboxylic anhydrides (alicyclic polycarboxylic anhydrides) such as carboxylic anhydrides (alicyclic polycarboxylic anhydrides), heptic anhydride, and hymic anhydride, and phthalic anhydride , Tetrabromophthalic anhydride, tetrachlorophthalic anhydride, nitrophthalic anhydride, trimellitic anhydride, methylcyclohexenetricarboxylic anhydride, pyromellitic anhydride Mellitic anhydride, 1,8; 4,
Aromatic polycarboxylic anhydrides such as 5-naphthalenetetracarboxylic dianhydride are included.

Preferred imide compounds include, for example,
N-hydroxysuccinimide, N-hydroxymaleimide, N-hydroxyhexahydrophthalimide, N, N'-dihydroxycyclohexanetetracarboxylic imide, N-hydroxyphthalimide, N-hydroxytetrabromophthalimide , N-hydroxytetrachlorophthalimide, N-acetoxyphthalimide, N-hydroxyhettimide, N-hydroxyhymic imide, N-hydroxytrimellitic imide, N, N'-dihydroxypyromellitic imide , N, N'-dihydroxynaphthalenetetracarboxylic imide. Particularly preferred compounds include:
Cyclic imide [N-hydroxyimide compounds derived from alicyclic polycarboxylic anhydrides, especially aromatic polycarboxylic anhydrides, such as N-hydroxyphthalimide, N-acetoxyphthalimide, etc.] Is included.

The imide compound can be prepared by a conventional imidization reaction, for example, by reacting the corresponding acid anhydride with hydroxylamine N
It can be prepared by reacting with H ₂ OH to open the acid anhydride group and then closing the ring to imidize the ring.

Such an imide compound can be used as a catalyst for various reactions (eg, oxidation reaction, carboxylation reaction, nitration reaction, sulfonation reaction, acylation reaction, radical coupling reaction, etc.). In particular, a carboxylic acid (such as an aliphatic dicarboxylic acid, an aromatic carboxylic acid, or a heterocyclic carboxylic acid), a ketone, or a lactone is selected with a high selectivity only by contacting a substrate with oxygen in the presence of the imide compound. And in yield.

The amount of the imide compound of the formula (I) used is
It can be selected in a wide range, for example, 1 ×
10 ⁻⁶ mol (1 × 10 ⁻⁴ mol%) to 1 mol (100 mol%), preferably 1 × 10 ⁻⁵ mol (1 × 10 ⁻³ mol%)
0.5 mol (50 mol%), more preferably 1 × 1
About 0 ^-4 mol (1 × 10 ^-2 mol%) to about 0.4 mol (40 mol%), and 1 × 10 ^-4 mol (1 × 10 ^-2 mol%)
It is often about 0.35 mol (35 mol%).

[Co-catalyst] The imide compound is used in combination with a metal catalyst (sometimes referred to as a metal co-catalyst or simply a co-catalyst). Examples of the co-catalyst include a metal compound, for example, a compound containing a Group 13 element of the periodic table (boron B, aluminum Al, etc.) such as a transition metal compound and a boron compound. The cocatalyst can be used alone or in combination of two or more.

The elements of the transition metal include, for example, elements belonging to Group 3 of the periodic table (eg, scandium Sc, yttrium Y, lanthanum La, cerium Ce, samarium S).
lanthanoid elements such as m, actinoid elements such as actinium Ac), Group 4 elements of the periodic table (such as titanium Ti, zirconium Zr, and hafnium Hf); Group 5 elements (such as vanadium V, niobium Nb, and tantalum Ta); Chromium Cr, molybdenum Mo, tungsten W, etc.), Group 7 elements (manganese Mn, etc.), Group 8 elements (iron F
e, ruthenium Ru, osmium Os, etc.), group 9 elements (cobalt Co, rhodium Rh, iridium Ir, etc.), group 10 elements (nickel Ni, palladium Pd, platinum Pt, etc.), group 11 elements (copper Cu, silver Ag, Au, etc.).

In particular, when combined with the imide compound represented by the formula (I), a lanthanoid element such as Ce, Ti
Group 4 element such as V, group 5 element such as V, 6 such as Mo and W
A compound containing a Group 7 element, a Group 7 element such as Mn, a Group 8 element such as Fe or Ru, a Group 9 element such as Co or Rh, a Group 10 element such as Ni, or a Group 11 element such as Cu has high oxidation activity. Show.

The co-catalyst is not particularly limited as long as it contains the above-mentioned element and has catalytic ability, and may be a hydroxide or the like. Usually, a metal oxide, an organic acid salt or an inorganic acid containing the above-mentioned element is used. It is often a salt, a halide, a coordination compound (complex) containing the metal element, a heteropolyacid or a salt thereof. Examples of the boron compound include, for example, borohydride (eg, borane, diborane, tetraborane, pentaborane, decaborane), boric acid (eg, orthoboric acid, metaboric acid, tetraboric acid), borate (eg, boric acid) Nickel, magnesium borate, manganese borate, etc.), boron oxides such as B ₂ O ₃ , nitrogen compounds such as borazane, borazene, borazine, boron amide, boron imide, BF ₃ , BCl ₃ , tetrafluoroborate, etc. And borate esters (for example, methyl borate, phenyl borate, etc.).

Examples of the organic acid salt include C _1-30 carboxylate (C _2-24 carboxylate, etc.) such as acetate, propionate, naphthenate, octylate, stearate and the like. As the inorganic acid salt, for example, nitrate,
Sulfate or phosphate may be mentioned. Examples of the halide include chloride and bromide.

The ligands forming the complex include alkoxy groups such as OH (hydroxo), methoxy, ethoxy, propoxy and butoxy groups, acyl groups such as acetyl and propionyl, and alkoxy groups such as methoxycarbonyl (acetato) and ethoxycarbonyl. Phosphorus such as carbonyl group, acetylacetonate, cyclopentadienyl group, halogen atom such as chlorine and bromine, CO, CN, oxygen atom, H ₂ O (aquo), phosphine (for example, triarylphosphine such as triphenylphosphine) Compound, NH
_And nitrogen-containing compounds such as ₃ (ammine), NO, NO ₂ (nitro), NO ₃ (nitrat), ethylenediamine, diethylenetriamine, pyridine and phenanthroline. In the complex or complex salt, the same or different ligands may be coordinated by one kind or two or more kinds.

Preferred complexes include those containing the above-mentioned transition metal elements. The transition metal element and the ligand can be appropriately combined to form a complex, for example, cerium acetylacetonate, cobalt acetylacetonate,
Ruthenium acetylacetonate, copper acetylacetonate and the like may be used.

The polyacid forming the heteropolyacid is, for example, an element belonging to Group 5 or 6 of the periodic table, for example, V (vanadic acid), Mo (molybdic acid) and W (tungstic acid).
In many cases, and the central atom is not particularly limited. Specific examples of the heteropolyacid include, for example,
Cobalt molybdate, cobalt tungstate,
Molybdenum tungstate, vanadium molybdate, vanadomolybdophosphate and the like can be mentioned.

As a co-catalyst, a co-catalyst composed of a Group 7 element and / or a Group 9 element [for example, a combination of a compound containing a Group 7 element and a compound containing a Group 9 element (particularly,
A combination of a manganese compound and a cobalt compound)] can efficiently produce an aliphatic dicarboxylic acid (particularly adipic acid) or an aromatic carboxylic acid (such as terephthalic acid).

The metal catalyst is preferably soluble in an aqueous solvent (particularly, an aqueous solvent such as water or a water-containing solvent). Examples of such a metal catalyst include organic acid salts (such as acetates), inorganic acid salts (such as sulfates), halides (such as chlorides), complexes, and heteropolyacids.

The catalyst system composed of the imide compound (I) and the cocatalyst may be a homogeneous system or a heterogeneous system. Further, the catalyst system may be a solid catalyst in which a catalyst component is supported on a carrier. As the carrier, a porous carrier such as activated carbon, zeolite, silica, silica-alumina and bentonite is often used. The supported amount of the catalyst component in the solid catalyst is about 0.1 to 50 parts by weight with respect to 100 parts by weight of the carrier. The amount of the cocatalyst carried is about 0.1 to 30 parts by weight based on 100 parts by weight of the carrier.

The amount of the cocatalyst used is, for example, 1 × 10 ^-6 mol to 0.7 mol, preferably 1 × 1 mol per mol of the substrate.
0 ^-5 mol to 0.3 mol, more preferably about 1 × 10 ^-5 mol to 0.1 mol (10 mol%), and 1 × 10 ^-6 mol
Mol to 1 × 10 ⁻² mol, especially 1 × 10 ⁻⁶ mol to 1 × 10
^It may be about ^-3 mol. When a heteropolyacid or a salt thereof is used as a cocatalyst, 0.1 to 25 parts by weight, preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the substrate,
More preferably, it is about 1 to 5 parts by weight.

The co-catalyst is usually 1 to 10,000 ppm, preferably 5 to 50 ppm by weight in the liquid phase reaction system.
It can be used at a concentration of about 00 ppm, more preferably about 10 to 300 ppm.

The ratio between the imide compound and the cocatalyst is
For example, imide compound / co-catalyst = 95 / 5-5 / 95
(Molar ratio), preferably about 90/10 to 20/80 (molar ratio), and more preferably about 85/15 to 50/50 (molar ratio).

[Substrate] The type of the substrate is not particularly limited, and various types of substrates disclosed in JP-A-9-327626, for example, hydrocarbons, alcohols, aldehydes, ketones, amines, and complexes are disclosed. Ring compounds, thiols,
Examples include sulfides and amides. The substrate may be a substrate that produces a water-soluble compound or a substrate that produces a water-insoluble compound. Preferred substrates produce water-insoluble compounds. Preferred substrates include hydrocarbons (such as cycloalkanes and polycyclic cycloalkanes), and methyl group-containing aromatic compounds.

Examples of cycloalkanes include cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, methylcyclohexane, ethylcyclohexane, dimethylcyclohexane, chlorocyclohexane, methoxycyclohexane, cyclooctane, cyclononane, cyclododecane, cyclopentadecane, And C _4-20 cycloalkane such as cyclooctadecane (preferably C _4-16 cycloalkane, more preferably C _4-10 cycloalkane). These cycloalkanes may be used alone or in combination of two or more.

Preferred cycloalkanes include C _4-10 cycloalkanes (preferably C _5-8 cycloalkanes) such as cyclohexane, methylcyclohexane and cyclooctane.

Polycyclic cycloalkanes include compounds having a tertiary carbon atom at the bridgehead (for example, bicyclic hydrocarbons such as bornane, norbornane, norbornene, and tricyclo [4.3.1.1 ^2,5 Hydrogenated products of tricyclic hydrocarbons such as undecane, homobredan and adamantane, tetracyclic hydrocarbons, terpenes, etc., and condensed polycyclic aromatic hydrocarbons (eg, decalin, perhydroanthracene, par Hydrophenanthrene).

As the aromatic compound having a methyl group,
At least one (for example, 1 to 10, preferably 1 to 8
) Is a compound in which the methyl group is substituted with an aromatic ring
The aromatic ring may be an aromatic hydrocarbon ring or an aromatic ring.
It may be any of heterocycles. Aromatic coal containing methyl group
Hydrogens include aromatic hydrocarbon rings (diphenylmethane,
Diphenylmethane, dibenzyl, stilbene, etc.
Or triaryl-C _1-3Methyl group in alkane)
Are substituted, for example, toluene, (o-,
m-, p-) xylene, trimethylbenzene (1, 2,
3-trimethylbenzene, 1,3,5-trimethylben
And tetramethylbenzene (1,2,3,4-
Tetramethylbenzene, 1,2,4,5-tetramethyl
Benzene, etc.), hexamethylbenzene, 4-t-butyl
1-methylbenzene, 2-methoxy-1-methylbenzene
Benzene, 1-methylnaphthalene, 2-methylnaphthale
1,5-dimethylnaphthalene, 2,5-dimethylna
Aroma substituted with about 1 to 6 methyl groups such as phthalene
Group hydrocarbons and the like. Preferred methyl group containing
Aromatic hydrocarbons have a methyl group substitution number in the molecule.
About 1 to 4 (especially 1 to 2) C_6-10Aromatic hydrocarbon
(Eg, toluene, xylene, tetramethylbenze)
) Are included.

Examples of the heterocyclic compound having a methyl group include compounds in which a heterocyclic ring is substituted with a methyl group, for example, 2-methylfuran, 3-methylfuran, 2-methylpyran, 3-methylpyran, 3,4-dimethylpyran, methyl Chroman,
Picolines (2-, 3- or 4-methylpyridine), lutidines (2,3-dimethylpyridine, 2,4-dimethylpyridine, 2,5-dimethylpyridine, 3,5-dimethylpyridine), collidines ( 2,3,4-trimethylpyridine, 2,3,5-trimethylpyridine, 2,4
6-trimethylpyridine, etc.), methylindoles (4-methylindole, 5-methylindole, 7-
And methyl indole.

The substrate is a substrate having various substituents, for example, an alkyl group having 2 or more carbon atoms (for example,
Ketones such as C _2-10 alkyl groups such as ethyl, propyl, butyl, t-butyl, hexyl and octyl groups, halogen atoms (such as fluorine, chlorine and bromine atoms) and carbonyl groups (such as cyclohexanone and adamantanone) ), A substrate having a hydroxyl group (alcohols such as cyclohexanol and adamantanol), a substrate having a carboxyl group (carboxylic acids such as carboxytoluene) or a derivative thereof (such as an ester), a mixture thereof (KA oil) and esters. (Cyclohexyl acetate, acetyloxytoluene, etc.) can also be used.

The imide compound has a catalytic action in various reactions (oxidation reaction, carboxylation reaction, nitration reaction, sulfonation reaction, acylation reaction, radical coupling reaction, etc.).

(Oxidation reaction) The reaction is carried out in an oxygen atmosphere. The oxygen source is not particularly limited, and pure oxygen may be used, or oxygen diluted with an inert gas such as nitrogen, helium, argon, or carbon dioxide may be used. It is preferable to use air from the viewpoint of economy as well as operability and safety. The amount of oxygen used can be selected according to the type of the substrate, and is usually 0.5 mol or more (for example, 1 mol or more), preferably 1 to 100 mol per 1 mol of the substrate.
Mole, more preferably about 2 to 50 moles, and the reaction is usually performed in an oxygen atmosphere containing an excess mole of oxygen.

The reaction may be carried out in a closed system after sufficient molecular oxygen has been supplied into the reactor in advance, or may be carried out by continuously passing molecular oxygen. When flowing continuously, the oxygen can be supplied at a flow rate corresponding to the used amount.

In the oxidation reaction, when the reaction is carried out in the presence of aldehydes (particularly, C _1-6 aldehydes such as acetaldehyde), ketones and / or alcohols, the oxidation reaction is accelerated, and An aliphatic dicarboxylic acid or an aromatic carboxylic acid can be produced efficiently. When a radical generator or a radical accelerator is used in combination, the reaction may be accelerated in some cases.

(Reaction Solvent) The reaction may be carried out in the absence of a solvent inert to the reaction, but can usually be carried out in the presence of a solvent. As the solvent, for example, formic acid, acetic acid,
Organic carboxylic acids such as propionic acid, trichloroacetic acid, and trifluoroacetic acid; hydrocarbons such as hexane, octane, and benzene; halogenated hydrocarbons such as chloroform, dichloromethane, dichloroethane, carbon tetrachloride, dichlorobenzene, and trifluoromethylbenzene Alcohols such as methanol, ethanol, propanol, butanol, octanol and 2-ethylhexanol; ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; esters such as methyl acetate, ethyl acetate and butyl acetate; dimethyl ether, diethyl ether, Ethers such as diisopropyl ether;
Nitro compounds such as nitrobenzene, nitromethane and nitroethane; nitriles such as acetonitrile, propionitrile and benzonitrile; amides such as formamide, acetamide, dimethylformamide (DMF) and dimethylacetamide; water; Can be

As the solvent, carboxylic acids (such as acetic acid), hydrocarbons, and alcohols (methanol, 2-
Ethyl hexanol, etc., ketones, esters, ethers, nitro compounds, nitriles, amides, aqueous solvents (such as aqueous organic carboxylic acids such as aqueous acetic acid) are used, and the substrate is often used as a solvent. In addition, as the water-containing solvent, an aqueous solution containing a high-concentration (for example, about 40 to 99% by weight, preferably about 60 to 95% by weight, particularly about 80 to 95% by weight) organic solvent may be used.

The reaction temperature is, for example, 0 to 300 ° C., preferably 15 to 250 ° C., more preferably 30 to 200 ° C.
° C, usually 50-190 ° C (especially 70-19 ° C).
(0 ° C.) in many cases.

The reaction can be carried out under normal pressure or under pressure.
100 atm (for example, 1.5 to 80 atm), preferably 2
In many cases, it is about 70 to 70 atm, more preferably about 3 to 50 atm. Reaction time (residence time in a flow reaction)
Can be appropriately selected from the range of, for example, about 1 minute to 48 hours, preferably 2 minutes to 24 hours, more preferably about 5 minutes to 8 hours, depending on the reaction temperature and pressure.

The water content of the reaction system is 30% by weight or less (for example, 0 to 30% by weight), preferably 0 to 20% by weight (for example, 0 to 18% by weight) based on the whole reaction system.
More preferably, when the content is adjusted to a range of about 0 to 15% by weight (for example, 0 to 10% by weight), the oxidation reaction can be promoted, the generation of by-products can be suppressed, and a reaction product such as carboxylic acid can be produced at a high yield Can be obtained at a rate.

The reaction operation may be carried out in a continuous, batch or semi-batch mode. The reaction may be performed by reactive distillation while removing water, or may be performed by reactive distillation in which water is removed in combination with a water separator such as a decanter. The reaction may be performed in two or more stages. As the reaction device, a conventional device can be used, and one or more devices may be used. If multiple devices are used, the devices may be connected in series and / or in parallel.

By such a reaction, various products, for example, alcohols or derivatives thereof (eg, esters),
Oxidation reaction products such as ketones, aldehydes and carboxylic acids can be produced. In addition, an organic carboxylic acid or a derivative thereof (eg, an ester) lower than the target compound may be generated. Further, with the oxidation reaction, the activity of the imide compound and / or the cocatalyst may be reduced, and a modified or decomposed product may be generated.

In the present invention, a mixture containing the imide compound and the metal catalyst (for example, a reaction mixture obtained by the above-mentioned reaction) is mixed with an aqueous solvent containing at least water and a non-aqueous solution capable of being separated from the aqueous solvent. The imide compound is separated into a water-insoluble solvent layer and the metal catalyst is separated into an aqueous solvent layer by using a neutral solvent. Therefore, this method is advantageous when the imide compound is a water-insoluble compound (such as an aromatic imide compound) and the metal catalyst is a water-soluble compound.

(Aqueous solvent containing at least water) As the aqueous solvent containing at least water, an aqueous solvent containing water as a main component can be used according to the solubility characteristics of the metal catalyst. This aqueous solvent includes water and other water-soluble organic solvents (eg, C _1-3 alcohols such as methanol, ketones such as acetone, ethers such as dioxane or tetrahydrofuran, lower aliphatic carboxylic acids such as acetic acid, Mixed solvents with nitriles such as acetonitrile).
These water-soluble solvents can be used alone or in combination of two or more.

The proportion of the organic solvent in the mixed solvent is, for example, 0 to 50% by weight (normally 0 to 20% by weight) with respect to water,
Preferably, it is about 0 to 5% by weight. Preferred aqueous solvents include water.

(Water-insoluble solvent) The water-insoluble solvent used in the extraction may be any solvent as long as it can be separated from the aqueous solvent, and examples thereof include alcohols (butanol, hexanol, 2-ethylhexanol, octanol, etc.). An aliphatic monohydric alcohol having 4 to 15 carbon atoms, an alicyclic alcohol having 5 to 15 carbon atoms such as cyclohexanol, and an aromatic alcohol having 6 to 12 carbon atoms such as benzyl alcohol)
Are particularly preferable, aliphatic hydrocarbons (hydrocarbons having 5 to 12 carbon atoms such as hexane and octane), alicyclic hydrocarbons (alicyclic hydrocarbons having 5 to 15 carbon atoms such as cyclohexane), Aromatic hydrocarbons (aromatic hydrocarbons having 6 to 12 carbon atoms such as toluene, pt-butyltoluene, xylene, and ethylbenzene), halogenated hydrocarbons (such as dichloromethane and chloroform), ketones (methyl ethyl ketone and diethyl) ketones, aliphatic ketones having from 4 to 15 carbon atoms such as methyl isobutyl ketone, cyclic ketones having 5 to 15 carbon atoms such as cyclohexanone), esters (C _2-10 aliphatic carboxylic acids such as methyl acetate -
C _1-10 alkyl ester, cyclohexyl acetate, etc.
_2-10 aliphatic carboxylic acid-C _5-10 cycloalkyl ester, C _2-10 aliphatic carboxylic acid-C such as phenyl acetate
C _7-12 aromatic carboxylic acid-C _1-10 alkyl ester such as _6-10 aryl ester and methyl benzoate, nitro compound (aliphatic nitro compound having 2 to 10 carbon atoms such as nitroethane, carbon number such as nitrobenzene) 6-10 aromatic nitro compounds), nitriles (valeronitrile,
Aliphatic nitriles having 5 to 12 carbon atoms such as capronitrile, benzonitrile, and 7-1 carbon atoms such as tolunitrile
2, aromatic nitriles and the like), ethers (chain ethers such as diethyl ether, diisopropyl ether and dibutyl ether), and mixed solvents thereof.

The water-insoluble solvent can be appropriately selected according to the kind of the imide compound. When the imide compound and the metal catalyst are separated from the reaction mixture, these hydrophobic (water-insoluble) solvents may be added to the reaction mixture after completion of the reaction, or may be used as the reaction solvent.

Preferred water-insoluble solvents include, for example, hydrocarbons (aliphatic or alicyclic hydrocarbons having 6 or more carbon atoms,
Examples thereof include aromatic hydrocarbons), alcohols (aliphatic alcohols having 4 or more carbon atoms), nitriles (such as aromatic nitriles such as benzonitrile), and mixed solvents thereof. Note that the hydrocarbons are preferably used as a mixed solvent with alcohols and / or nitriles. Particularly preferred non-water-soluble solvents include alcohols that can be separated from water [alcohols having 4 or more carbon atoms (for example, alcohols having 4 to 12 carbon atoms)] and hydrocarbons (aliphatic having 6 or more carbon atoms). Hydrocarbons (e.g., aliphatic hydrocarbons having 6 to 12 carbon atoms), nitriles (e.g., _C7-12 aromatic nitriles), and mixed solvents thereof.

When a hydrophobic solvent is used as a reaction solvent,
After the reaction, it can be used as a separation solvent for an aqueous solvent. When a hydrophobic substrate (for example, hydrocarbons) is used as the substrate, if the substrate is used as a reaction solvent, after the reaction, the remaining substrate can be used as a separation solvent for an aqueous solvent.

(Extraction operation) The extraction operation is carried out by mixing a mixture (mixture) containing an imide compound and a metal catalyst, or a reaction mixture obtained by reacting a substrate in the presence of a catalyst system containing an imide compound and a metal catalyst, or a reaction mixture thereof. Processed product (for example, a mixture that has been subjected to processes such as concentration, filtration, extraction, distillation, and crystallization)
, The aqueous solvent and the water-insoluble solvent are added, mixed by stirring or the like, and separated.

The ratio between the aqueous solvent and the hydrophobic (non-water-soluble) solvent can be appropriately selected according to the type of the imide compound and the metal catalyst. For example, the former / the latter (weight ratio) = 0.
01/1 to 10/1, preferably 0.05 / 1 to 5 /
1, more preferably about 0.1 / 1 to 3/1, and usually about 0.2 / 1 to 2/1.

The extraction may be performed by any method such as a batch method and a continuous method, and may be performed in multiple stages as necessary. The number of times the reaction mixture is extracted using the hydrophilic solvent and the hydrophobic solvent is, for example, about 1 to 5 times, and usually about 1 to 3 times.

The extraction may be heated, for example, at an extraction temperature of 0 to 100 ° C., preferably about 5 to 70 ° C. (eg, about 15 to 70 ° C.), and more preferably about 10 to 70 ° C.
５０50 ° C., and usually is often extracted at a temperature of about 15-50 ° C. If necessary, a shearing force may be applied to enhance the extraction efficiency, and the extraction may be performed under normal pressure or under pressure.

By this extraction operation, the metal catalyst was transferred to the aqueous solvent phase, and the imide compound was transferred to the water-insoluble solvent phase.
The imide compound and the metal catalyst can be separated. The separated imide compound and metal catalyst may be recycled to the reaction system. Further, the imide compound and the metal catalyst may be regenerated if necessary and recycled to the reaction system. For example, the recovered metal catalyst or metal component may be regenerated to a carbonate or an acetate if necessary, or after incineration and incineration, the metal component may be recovered and regenerated and recycled to the reaction system. Recovery of metal catalysts and metal components includes crystallization, filtration (filtration washing, etc.), adsorption (adsorption and desorption by ion exchange resin etc.),
Drying or a conventional method combining these can be performed. By such an operation, the imide compound remaining in the aqueous solvent phase can be further separated.

When the mixture is a reaction mixture obtained by reacting a substrate with an imide compound and a metal catalyst in the presence of the imide compound and a metal catalyst, the reaction mixture can be preliminarily mixed with a component containing a reaction product, an imide compound and a metal. After separating the component containing the catalyst, the aqueous solvent and the water-insoluble solvent, the imide compound and the metal catalyst may be separated, without separating the reaction product, from the reaction mixture from the reaction mixture, by the solvent, The crystallization component containing the imide compound and the non-crystallization component containing the metal catalyst may be separated. In the latter case,
The reaction product partitions into an aqueous or non-aqueous solvent phase, depending on its solubility characteristics.

In the present invention, the target reaction product (target compound) is separated from the reaction mixture by distributing the imide compound and the metal catalyst to the solvent phase by using a specific solvent. The imide compound and the metal catalyst may be separated.

In order to separate solid components and impurities in the reaction mixture, the reaction mixture may be subjected to a separation treatment such as a filtration treatment and then subjected to a separation treatment.

In the separation method using various solvents such as extraction and crystallization, the solvent used in the reaction product separation step is a solvent capable of separating the reaction product, the imide compound and the metal catalyst. Any solvent may be used as long as the reaction product is distributed to the solvent phase and the imide compound and / or the metal catalyst are precipitated. As the solvent, a solvent that can crystallize a reaction product and partition or extract the imide compound and the metal catalyst in a solvent phase is usually used.
Therefore, the target compound is preferably a reaction product that can be crystallized by a solvent, and may be, for example, an alcohol derivative (eg, an ester) or an aldehyde.
Usually, alcohols and ketones, preferably carboxylic acids.

In the present invention, in particular, water-insoluble compounds (for example, compounds which are solid at ordinary temperature (about 15 to 25 ° C.)) such as carboxylic acids (for example, adipic acid and the like having 6 or more carbon atoms, preferably 6 to 16 carbon atoms). , More preferably 6 to 12) aliphatic dicarboxylic acids and aromatic carboxylic acids), especially aromatic carboxylic acids, are useful to be separated from imide compounds and / or metal catalysts.

When the reaction is carried out in the presence of a solvent, the reaction mixture may be concentrated prior to crystallization of the target compound, or the reaction mixture may be subjected to the crystallization step without concentration. When the reaction is performed in the presence of a solvent, a solvent that is a poor solvent for the reaction product and a good solvent for the imide compound and the metal catalyst may be used as the reaction solvent. The solvent may be capable of dissolving the reaction product, imide compound and metal catalyst at the reaction temperature. Such a solvent can be used as a crystallization solvent, and by cooling, the reaction product can be crystallized from the reaction mixture, and the imide compound and the metal catalyst can be distributed in the solvent phase. For example, when the target compound is a water-insoluble carboxylic acid (especially aromatic carboxylic acid), lower carboxylic acids (C _1-4 alkane carboxylic acids such as acetic acid, particularly water-soluble carboxylic acids, etc.) and alcohols as reaction solvents (C _1-10 such as methanol and 2-ethylhexanol
By using an alcohol or a water-containing solvent, the water-insoluble carboxylic acid can be efficiently crystallized from the reaction mixture, and an imide compound (such as an aromatic imide compound) and a metal catalyst (such as a carboxylate) are dissolved in a solvent phase. Can be distributed.

Crystallization of the target compound can be carried out by crystallization by cooling or crystallization using a crystallization solvent (solvent crystallization). Cooling crystallization includes a target compound and a crystallization solvent,
The reaction can be performed by cooling a reaction mixture or a mixture heated to an appropriate temperature (for example, about 70 to 200 ° C.) to about −10 ° C. to 150 ° C. (particularly room temperature). In the solvent crystallization, the target compound may be crystallized by adding a solvent to the mixture containing the target compound.The solvent is added to the mixture, and the target compound is heated and cooled in the same manner as described above. It may be crystallized. After concentrating the mixture containing the target compound, a solvent may be added.

Examples of the crystallization or partitioning solvent include various solvents exemplified in the above-mentioned reaction solvent, for example, carboxylic acids (C _1-4 alkane carboxylic acids such as formic acid, acetic acid and propionic acid, particularly C _2-3 alkane) Carboxylic acids), hydrocarbons (aliphatic hydrocarbons such as hexane and octane, alicyclic hydrocarbons such as cyclohexane, cyclopentane and decalin, and aromatic hydrocarbons such as ethylbenzene, toluene and xylene), Alcohols (methanol,
Aliphatic alcohols such as ethanol, propanol, isopropanol, butanol, isobutanol, octanol and 2-ethylhexanol; ketones (aliphatic ketones such as acetone, methyl ethyl ketone, diethyl ketone and methyl isobutyl ketone); esters ( Acetates and lactates such as methyl acetate, ethyl acetate and butyl acetate; ethers (chain ethers such as dimethyl ether, diethyl ether, diisopropyl ether and di-n-butyl ether; cyclic ethers such as tetrahydrofuran and dioxane) , Alkylpyridines such as α-picoline, β-picoline and γ-picoline, halogenated hydrocarbons such as methylene chloride and chloroform, and nitro compounds (nitromethane such as nitromethane and nitroethane). Alkanes), nitriles (acetonitrile, propionitrile, benzonitrile, etc.), amides (formamide, acetamide, dimethylformamide (DMF), dimethylacetamide, etc.), dimethyl sulfoxide, carbon disulfide, carbon tetrasulfide, petroleum ether , Water, aqueous solvents (acetic acid aqueous solution,
Aqueous solution containing water-soluble organic solvent such as alcohol aqueous solution)
Is included. These solvents may be mixed and used as a crystallization solvent.

The crystallization or partitioning solvent is usually an aqueous solvent or a water-soluble solvent, for example, carboxylic acids (eg, C _2-3 alkanecarboxylic acids such as acetic acid) and alcohols (eg, C ₁ such as methanol, ethanol and isopropanol). _And at least one solvent selected from ketones, nitriles, amides, and water, and a mixed solvent thereof (eg, an aqueous solvent). The hydrated solvent is, for example, 5 to 95% by weight, preferably 5 to 95% by weight.
An aqueous solution containing about 75% by weight, particularly about 5% to 50% by weight of an organic solvent may be used. Usually, water or a mixed solvent of water and a water-soluble solvent is used as the crystallization solvent.

When crystallization is performed by adding a crystallization solvent to the object to be treated containing the target compound, the amount of the crystallization solvent is not particularly limited as long as the target compound can be crystallized. 1 to 100 parts by weight of the object containing the compound
It may be about 0 to 500 parts by weight.

In a preferred embodiment of the present invention, an aromatic carboxylic acid (benzene carboxylic acid, heterocyclic carboxylic acid, etc.) as a target compound, an aromatic imide compound as an imide compound, and an aqueous solvent as a metal catalyst are used. is applied to separation of soluble compounds (especially water-soluble metal catalyst), as crystallization or distribution solvent used in the separation of the reaction product, C _1-4
Alkane carboxylic acids (especially C _2-3 alkane carboxylic acids such as acetic acid), alcohols (C _1-10 alkyl alcohols), mixed solvents thereof, or hydrated solvents thereof are used.

The crystallization component containing the target compound and the solvent phase (non-crystallization component) containing the imide compound and the metal catalyst can be separated by a simple operation such as filtration, decantation and centrifugation. The crystallized component may be purified by operations such as washing, recrystallization (crystallization), and extraction, if necessary.

The solvent phase (non-crystallized component) is subjected to a metal catalyst separation step using the aqueous solvent and the water-insoluble solvent,
The imide compound and the metal catalyst are separated. In order to increase the separation efficiency, it is advantageous to subject the solvent phase to a concentration step to concentrate (or remove the solvent) and to perform an extraction treatment with the solvent. Further, crystallization may be generated in association with the extraction treatment (treatment such as addition of an extractant, shaking, and liquid separation). Therefore, the concentrate is treated with a solvent (such as an aqueous solvent) (for example,
(Addition, shaking or extraction treatment, etc.) to separate into a crystallization component (crystallized product containing an imide compound) and a solvent phase (aqueous solvent phase or the like), and the metal catalyst may be recovered from the solvent phase. Also,
The concentrate may be extracted with an aqueous solvent, separated into an organic phase containing an imide compound and an aqueous phase containing a metal catalyst, and the metal catalyst may be recovered from the aqueous phase (aqueous solvent phase).

Among the by-products, carboxylic acid precursors (alcohols or derivatives thereof corresponding to the substrate, monocarboxylic acids, ketones, aldehydes, etc.) are separated from the crystallization components separated in the crystallization step and / or Or distribution (extraction, etc.), crystallization, adsorption, hydrolysis, saponification, neutralization,
It may be separated by distillation (evaporation or the like), filtration (filtration washing or the like), drying or a combination thereof, and may be recycled to the reaction system if necessary.

[0090]

According to the present invention, an imide compound and a metal catalyst can be efficiently separated by using an aqueous solvent and a water-insoluble solvent. Further, since the reaction product, the imide compound and the metal catalyst are separated from the reaction mixture, and the metal catalyst is extracted from the solvent phase, the reaction product and the metal catalyst can be efficiently separated.

[0091]

EXAMPLES The present invention will be described below in more detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 4.028 g (50 mmol) of cyclohexane, 0.816 g (5 mmol) of N-hydroxyphthalimide, 0.015 g (0.05 g) of cobalt (II) acetylacetonate.
025 mmol) and a mixture of benzonitrile (200 ml) were reacted at 100 ° C. for 6 hours in an oxygen atmosphere to obtain 2.946 g (35 mmol) of cyclohexane.
0.981 g (10 mmol) of cyclohexanone, 0.731 g (2 mmol) of adipic acid, N-hydroxyphthalimide, phthalimide, phthalic acid, cobalt (II)
A reaction mixture containing acetylacetonate and benzonitrile was obtained. Cyclohexane (20 ml) and water (150 ml) were added to the reaction mixture at 26 ° C., and after complete mixing, the mixture was separated into an aqueous layer and an organic layer.
Water was further added to the obtained organic layer, mixed thoroughly, and separated into an aqueous layer and an organic layer. As a result of analyzing the aqueous layer and the organic layer by liquid chromatography, the extraction rate of N-hydroxyphthalimide into the organic layer (based on N-hydroxyphthalimide contained in the reaction mixture) was 79%, and the extraction rate into the organic layer of phthalimide was 79%. Extraction rate of 82%, extraction rate of phthalic acid to organic layer is 65%, extraction rate of cobalt (II) acetylacetonate to aqueous layer (based on cobalt (II) acetylacetonate contained in reaction mixture) ) Was 95%.

Example 2 25 g (164.2 mmol) of adamantanol, N-
5.36 g of hydroxyphthalimide (32.8 mmol
l), vanadium (II) acetylacetonate 0.11
4 g (0.328 mmol), benzonitrile (150
A mixture of acetic acid (150 ml) and acetic acid (150 ml) was reacted under an oxygen atmosphere at 85 ° C. for 20 hours. As a result, adamantanol 1.41 g (9.2 mmol), adamantanediol 13.9 g (82.6 mmol), adamantanetriol A reaction mixture containing 10.5 g (57.5 mmol) of N-hydroxyphthalimide, phthalimide, phthalic acid, vanadium (III) acetylacetonate and benzonitrile was obtained. After acetic acid was distilled off from the reaction mixture, benzonitrile was added to make up to 300 ml, and at 26 ° C., 300 ml of water was added. After complete mixing, the mixture was separated into an aqueous layer and an organic layer. Water was further added to the obtained organic layer, mixed thoroughly, and separated into an aqueous layer and an organic layer.
As a result of analyzing the aqueous layer and the organic layer by liquid chromatography, the extraction rate of N-hydroxyphthalimide into the organic layer (based on N-hydroxyphthalimide contained in the reaction mixture) was 80%, and the extraction rate into the organic layer of phthalimide was 80%. Is 86%, phthalic acid is 75% in the organic layer, and vanadium (III) acetylacetonate is in the aqueous layer (based on vanadium (III) acetylacetonate contained in the reaction mixture). ) Was 93%.

Example 3 9.3 g (100 mmol) of 2-methylpyridine, N-
1.6 g (10 mmol) of hydroxyphthalimide, 0.15 g (0.5 g) of cobalt (II) acetylacetonate
mmol), and a mixture of acetic acid (250 ml) was reacted at 100 ° C. for 6 hours under an oxygen atmosphere. As a result, the conversion of 2-methylpyridine was 82%, and the yield of 2-pyridinecarboxylic acid (picolinic acid) was 77%. Obtained. After distilling off acetic acid from the reaction mixture, 400 ml of benzonitrile and
After adding 00 ml and shaking well, the mixture was allowed to stand and liquid was separated into two layers. Add 400 ml of water to the obtained organic layer.
Was added, and the mixture was shaken well and allowed to stand still to separate into two layers. As a result of analyzing the aqueous layer and the organic layer by liquid chromatography, the extraction rate of N-hydroxyphthalimide into the organic layer (based on N-hydroxyphthalimide contained in the reaction mixture) was 83%, and the extraction rate into the organic layer of phthalimide was 83%. Extraction rate of 85%, extraction rate of phthalic acid to the organic layer is 66%,
The extraction rate of cobalt (II) acetylacetonate into the aqueous layer (based on cobalt (II) acetylacetonate contained in the reaction mixture) was 97%.

Example 4 30.68 kg (0.23 kmol) of adamantane, N
5.51 kg of hydroxyphthalimide (0.0001
A mixture of 204.57 kg of acetic acid and 204.57 kg of acetic acid was reacted at 90 ° C. for 4.5 hours in an oxygen atmosphere, and 0.28 kg (0.002 kmol) of adamantane, 6.48 kg (0.04 kmol) of adamantanol, and 2 .95 kg (0.02 kmol), adamantanediol 10.73 kg (0.06 kmol), adamantanetriol 2.78 kg (0.02 kmol),
A reaction mixture containing 0.88 kg of N-hydroxyphthalimide, 0.22 kg of phthalimide, 0.05 kg of vanadium (III) acetylacetonate and acetic acid was obtained. After acetic acid was distilled off from the reaction mixture, water was added.
After adding 31 kg and stirring at 40 ° C., the precipitate was removed by filtration. A mixed liquid of 71.60 kg of n-butanol and 71.60 kg of n-heptane was added to the filtrate, and the mixture was completely mixed at 25 ° C., and then separated into an aqueous layer and an organic layer.
A mixed solution of 61.37 kg of n-butanol and 61.37 kg of n-heptane was added to the obtained aqueous layer, and the mixture was completely mixed at 25 ° C., and then separated into an aqueous layer and an organic layer. After this operation was repeated once, the aqueous layer and the organic layer were analyzed by liquid chromatography. As a result, the extraction ratio of N-hydroxyphthalimide into the organic layer (N
100%, the extraction rate of phthalimide into the organic layer was 100%, and vanadium (II
I) The extraction rate of acetylacetonate into the aqueous layer (based on vanadium (III) acetylacetonate contained in the filtrate) was 83%.

Continuing on the front page (72) Inventor Mami Shimamura 1367-21 F-term of the new resident at Aboshi-ku, Himeji-shi, Hyogo Pref. BC42A BC43A BC44A BC45A BC49A BC50A BC51A BC52A BC53A BC54A BC54B BC55A BC56A BC57A BC58A BC59A BC60A BC61A BC62A BC65A BC66A BC67A BC67B BC68A BC69A BC70A BC71A BC72A BC73A BC74A BC75A BEB19 BE11CAB

Claims (6)

[Claims] 1. A compound represented by the following formula (I): (Wherein, X represents an oxygen atom, a hydroxyl group or an acyloxy group) From a mixture containing an imide compound having an imide unit represented by the formula (I) and a metal catalyst, an aqueous solvent containing at least water, A method in which an imide compound is distributed to a water-insoluble solvent layer and a metal catalyst is distributed to an aqueous solvent layer using a water-insoluble solvent capable of liquid separation. 2. The method according to claim 1, wherein the aqueous solvent is water. 3. The method according to claim 1, wherein the water-insoluble solvent is at least one selected from alcohols, hydrocarbons, nitriles, and a mixed solvent thereof. 4. The method according to claim 1, wherein the water-insoluble solvent is an alcohol, a mixed solvent of a hydrocarbon and an alcohol, or a mixed solvent of a hydrocarbon and a nitrile. 5. The imide compound is an aromatic imide compound, and the metal catalyst is a water-soluble compound and is at least one selected from a transition metal compound and a compound containing a Group 13 element of the periodic table. the method of. 6. The aqueous solvent is water, the alcohol having 4 or more carbon atoms, and the water-insoluble solvent is at least one selected from hydrocarbons having 6 or more carbon atoms, aromatic nitriles, and a mixed solvent thereof. The method of claim 1, wherein