JP5801727B2 - Peroxo complex - Google Patents

Description

The present invention relates to peroxo complexes. More specifically, the present invention relates to a peroxo complex that can be suitably used as an oxidation catalyst, particularly as an epoxidation reaction catalyst for an unsaturated bond-containing compound such as an alkene.

A peroxo complex is a compound having a structure in which a peroxo group is coordinated to a metal element as a central atom, and a peroxo group is coordinated to a transition metal element such as Mo (IV), W (VI), V (V), Transition metal peroxo complexes and the like are known. These can be obtained by reacting hydrogen peroxide with a transition metal element, and can exhibit a function as an oxidation catalyst due to its unique structure. For example, a tungsten peroxide compound having selenium element (Se) or tellurium element (Te) sandwiched between two oxygen atoms coordinated to two central atoms with tungsten (W) as a central atom is disclosed (patent) Reference 1 etc.). Such a tungsten peroxide compound is different from a tungsten peroxo compound having elements such as Si, P, As, and S that have been reported so far, and there is a problem when such a compound is used as an oxidation catalyst, that is, the compound Solves problems such as the need for an equivalent amount to the substrate and the necessity of using expensive phosphorus-containing compounds and halogen-containing solvents, and provides high catalytic activity in the epoxidation reaction of unsaturated bond-containing compounds. It is shown.

By the way, as a reaction to which an oxidation catalyst is applied, conversion to an epoxy compound (epoxide) by an epoxidation reaction of a compound having an ethylenically unsaturated double bond such as olefin is a basic reaction in industrial organic chemistry. It is. Usually, olefin is converted into an epoxy compound using hydrogen peroxide (H ₂ O ₂ ) as an oxidizing agent. In this way, the reaction of oxidizing raw material compounds using environmentally friendly H ₂ O ₂ as an oxidizing agent and using an oxidation catalyst is performed by an environmentally friendly process for industrial production of various useful compounds including epoxides. It is effective to implement. The compounds produced in this way are useful as intermediates and raw materials used in the production of various industrial products, for example, important intermediates in the synthesis of useful compounds such as epoxy resins, surfactants, and pharmaceuticals. It can be used as a product.

JP 2010-76997 A (page 1-4, etc.)

Peroxo complexes as described above are attracting attention in various technical fields such as structural chemistry, biochemistry, catalysts, and materials.
Until now, peroxotungstates such as [PO ₄ {WO (O ₂ ) ₂ } ₄ ] ³⁻ having a μ-η ¹ : η ² —O ₂ site centered on a heteroatom are active in various oxidation reactions It has become clear. In addition, it has recently been clarified that complexes having an organic ligand such as [PPh ₄ ] [WO (O ₂ ) ₂ (C ₉ H ₆ ON) ₂ ] also exhibit high activity in oxidation reactions. Requires the addition of acid or base. On the other hand, [{WO (O ₂ ) ₂ } ₂ (μ-η ¹ : η ¹ -O ₂ )] ^2- or [W ₄ O ₆ (O ₂ ) ₆ ( There is almost no oxidation activity of peroxotungstate such as OH) ₂ (H ₂ O) ₂ ] ²⁻ , and a peroxotungstate catalyst having no heteroatoms and organic ligands and showing high activity in oxidation reaction is still known. Absent.
Patent Document 1 solves the problem of tungsten peroxo compounds having elements such as Si, P, As, and S, but includes selenium element (Se) or tellurium element (Te). There was room for improvement in order to make the molecular structure free of these elements.

As described above, a compound that does not have a heteroatom or an organic ligand and does not have a special element such as selenium element (Se) or tellurium element (Te) and has high activity in an oxidation reaction If possible, a compound useful as an oxidation catalyst or the like can be easily prepared. In addition, a novel peroxo complex that can be expected to be used in various technical fields can be provided. Furthermore, in fine chemicals synthesis, which requires high selectivity such as alkene epoxidation, an oxidation reaction with a stoichiometric amount of peracid is performed, but the use of dangerous reagents and the amount of by-products are reduced. The development of a catalyst is desired. New peroxo complexes that exhibit catalytic activity without heteroatoms, organic ligands, and special elements are expected as such catalysts.

The present invention has been made in view of the above-described situation, shows high activity in oxidation reactions without having heteroatoms, organic ligands, and special elements, and as an oxidation catalyst, in particular, unsaturated compounds such as alkenes. An object of the present invention is to provide a peroxo complex that can be suitably used as a catalyst for epoxidation of a bond-containing compound.

The present inventor has made various studies on peroxo complexes exhibiting activity as an oxidation catalyst. As a result, the mononuclear structure has a structure in which a plurality of peroxo groups are coordinated to a central atom as a bidentate ligand. In a peroxo complex, the central atom is selected as a specific transition metal element and has a structure in which a halogen atom is coordinated to the central atom, or consists of a plurality of central atoms, and a plurality of peroxo groups are bidentate. In a binuclear peroxo complex having a structure coordinated to a central atom as a ligand, the central atom is selected and specified, and one of the oxygen atoms of the peroxo group is coordinated to another central atom, and It has been found that when a structure having a structure in which central atoms are bonded to each other only by this method, the oxidation reaction is highly active. In particular, tungsten peroxo complexes with tungsten as the central atom have lower hydrogen peroxide resolution than peroxo complexes with metal species such as molybdenum and vanadium as the central atom, so the activity of oxidation reaction systems using them is higher. It becomes. Therefore, also in the mononuclear peroxo complex and the binuclear peroxo complex, the form in which the central atom is tungsten is important.
These mononuclear and binuclear peroxo complexes are useful as novel peroxo complexes that do not have heteroatoms, organic ligands, or special elements and exhibit high activity in oxidation reactions. The present inventors have arrived at the present invention.

That is, the first aspect of the present invention is a peroxo complex in which a peroxo group is coordinated to a central atom, and the central atom is at least one selected from groups 5 and 6 of the periodic table The peroxo complex is a mononuclear peroxo complex composed of one central atom, and has a structure in which a plurality of peroxo groups are coordinated to the central atom as a bidentate ligand, A peroxo complex having a structure in which a halogen atom is coordinated to a central atom.
In the present specification, the first aspect of the present invention is also simply referred to as “mononuclear peroxo complex”.

The second aspect of the present invention is a peroxo complex in which a peroxo group is coordinated to a central atom, and the central atom is at least one selected from groups 5 and 6 of the periodic table The peroxo complex is a binuclear peroxo complex composed of a plurality of central atoms, has a structure in which a plurality of peroxo groups are coordinated to the central atom as a bidentate ligand, and the peroxo group Is a peroxo complex having a structure in which one of the oxygen atoms is coordinated to another central atom and the central atoms are bonded to each other only by the oxygen atom.
In the present specification, the second aspect of the present invention is also simply referred to as “binuclear peroxo complex”.
The present invention is described in detail below.
A combination of two or more preferred embodiments of the present invention described below is also a preferred embodiment of the present invention.

A preferable form of the mononuclear peroxo complex has a structure in which two peroxo groups are coordinated as a bidentate ligand to one central atom, and two oxygen atoms and one halogen atom are coordinated to the central atom. It is the form which becomes the ordered structure. In this mononuclear peroxo complex, the two oxygen atoms coordinated to the central atom are preferably oxygen atoms derived from H ₂ O.
The preferred form of the binuclear peroxo complex has a structure in which two peroxo groups are coordinated as bidentate ligands to each of a plurality of central atoms, and each of the central atoms has two oxygen atoms and one This is a form in which μ-O (oxygen atom bonding central atoms) is coordinated. In this binuclear peroxo complex, one of the two oxygen atoms coordinated to each of the central atoms is one of the two oxygen atoms of the peroxo group coordinated to the adjacent central atom. .

In the preferred form, the oxygen atom including the peroxo group and μ-O may be a sulfur atom, but an oxygen atom is most preferred.
In the present invention, when an atom is coordinated to a central atom, it is preferable to form a coordinate bond, but it may be a covalent bond, an ionic bond, a bond by intermolecular force, or the like. It may be recognized that a certain atom is linked to the central atom by some chemical bonding force and coordinated to the central atom.

When a preferred form of the mononuclear peroxo complex is represented by a chemical formula, it is represented by the following general formula (1) or (2). When a preferred form of the binuclear peroxo complex is represented by a chemical formula, the following general formula (3) or It is represented by (4).
[XO (O ₂ ) ₂ (H ₂ O) Y] ⁻ (1)
[XO (O ₂ ) ₂ Y] ²⁻ (2)
[{XO (O ₂ ) ₂ } ₄ (μ-O) ₂ ] ^4- (3)
[{XO (O ₂ ) ₂ } ₄ (μ-O) ₂ ] ^8- (4)
In the above general formula, X represents a central atom. In the case of a binuclear peroxo complex, a plurality of Xs may be the same or different. Y represents a halogen atom.

The peroxo complex of the present invention may be a compound in the form of an anion as represented by the above general formula, or may be a compound having a cation. In the case of having a cation, the mononuclear peroxo complex and the binuclear peroxo complex can be represented by the following general formulas (1 ′) to (4 ′), respectively.
A [XO (O ₂ ) ₂ (H ₂ O) Y] (1 ′)
_An [XO (O ₂ ) ₂ Y] (2 ′)
_{A n [{XO (O 2} ) 2} 4 (μ-O) 2] (3 ')
A _{n [{XO (O 2) 2}} 4 (μ-O) 2 ] (4 ')
In the above general formula, X and Y are the same as described above. A represents a cation. n represents the number of 1-8. When there are a plurality of A, A may be the same or different.

In the peroxo complex of the present invention, the central atom (represented by X in the general formulas (1) to (4) and (1 ′) to (4 ′)) is group 5 and 6 in the periodic table. And at least one transition metal element selected from the group.
In addition, the said group number will be the 5th group A (VA) and the 6th group A (VIA), if it represents with an old family number.
Examples of the transition metal element belonging to Group 5 and Group 6 include vanadium (V), molybdenum (Mo), and tungsten (W). In addition, niobium (Nb), tantalum (Ta), Chrome (Cr) etc. are mentioned.
In the above general formulas, the general formulas (1), (3), (1 ′), and (3 ′) represent transition metal elements (molybdenum (Mo), tungsten (W) where X is selected from Group 6. ), Chromium (Cr), etc.), and the general formulas (2), (4), (2 ′) and (4 ′) are transition metal elements (vanadium (V ), Niobium (Nb), tantalum (Ta), etc.).
In the present invention, it can be said that, regardless of which element is selected, the homologous element has the same chemical characteristics, and thus exhibits the same catalytic action although the effect is different. Even if the group numbers are different, the group numbers are adjacent to each other, and all have the characteristics as a transition metal element. Therefore, in the embodiments other than the embodiment in which the action as a catalyst is proved in the examples described later. Even if it exists, it can be said that although the effect is different, the same catalytic action is exhibited.

The central atom is preferably tungsten and / or molybdenum. That is, in the case of a mononuclear peroxo complex, the central atom is preferably tungsten or molybdenum, and in the case of a dinuclear peroxo complex, all the central atoms may be tungsten, all may be molybdenum, Tungsten and molybdenum may be mixed.
The most preferred form of the central atom is tungsten. In this case, in the case of a mononuclear peroxo complex, one central atom is in a form of tungsten, whereas in the case of a dinuclear peroxo complex, all of the plurality of central atoms are in a form of tungsten. These forms having tungsten as a central atom can further increase the activity as an oxidation catalyst.

In the above-mentioned binuclear peroxo complex, the number of the plurality of central atoms may be 2 or more, and examples thereof include 4, 6, 8, 10, 12, and the like. The number is preferably 4 or more, 4, 6, 8, 10, 12, etc., more preferably 4. The most preferred form is a form with 4 central atoms and all tungsten. Thus, when there are four central atoms, μ-O is two. That is, two μ-Os exist between one set of atomic groups having two central atoms connected by a peroxo group and another set of atomic groups, and the central atoms are connected to each other.

The raw material having the central atom is not particularly limited as long as it has the central atom, and examples thereof include the following. Examples of the tungsten raw material include lithium tungstate, sodium tungstate, potassium tungstate, cesium tungstate, calcium tungstate, barium tungstate, tungstic acid, and tungsten oxide, and tungstic acid is preferable. Examples of the vanadium raw material include vanadium oxide, lithium metavanadate, sodium metavanadate, potassium metavanadate, vanadium sulfate, and the like. Examples of the molybdenum raw material include lithium molybdate, sodium molybdate, potassium molybdate, cesium molybdate, calcium molybdate, barium molybdate, molybdic acid, and molybdenum oxide. Furthermore, examples of the niobium raw material include vanadium oxide, lithium niobate, sodium niobate, and potassium niobate. Examples of the tantalum raw material include tantalum oxide, lithium tantalate, sodium tantalate, potassium tantalate, and the like. Examples of the chromium raw material include chromium oxide, sodium chromate, chromium nitrate, and chromium acetate.

As said halogen atom (what is represented by Y of general formula (1), (1 ')), a chlorine atom, a fluorine atom, a bromine atom, and an iodine atom are mentioned, Preferably it is a chlorine atom.
Examples of the halogen atom raw material include hydrogen fluoride, hydrochloric acid, hydrogen bromide, hydrogen iodide, fluorine, chlorine, bromine and iodine, and hydrochloric acid is preferable.

Examples of the cation (represented by A in the general formulas (1 ′) to (4 ′)) include protons, alkali metal cations, alkaline earth metal cations, ammonium cations, quaternary organic group-containing ammonium cations, Examples include quaternary organic group-containing phosphonium cations. In the case of a liquid phase reaction, the catalyst can be made homogeneous or heterogeneous depending on the type of solvent and cation. Moreover, a proton, a quaternary organic group containing ammonium cation, and a quaternary organic group containing phosphonium cation are preferable from the point which has high catalyst activity in the epoxidation reaction of an unsaturated bond compound.
The four organic groups in the quaternary organic group-containing ammonium cation may all be the same or different, and are preferably all the same alkyl group. As the said organic group, Preferably it is C1-C12, More preferably, it is C1-C10, More preferably, it is linear C1-C8. That is, the quaternary organic group-containing ammonium cation preferably has 4 to 48 carbon atoms, and more preferably has 4 to 40 carbon atoms.
Examples of the quaternary organic group-containing ammonium cation include, for example, tetramethylammonium cation, tetraethylammonium cation, tetrapropylammonium cation, tetrabutylammonium cation, tributylmethylammonium cation, trioctylmethylammonium cation, trilaurylmethylammonium cation, benzyl Examples include trimethylammonium cation, benzyltriethylammonium cation, benzyltributylammonium cation, and cetylpyridinium cation. Among these, tetramethylammonium cation, tetraethylammonium cation, tetra-n-propylammonium cation, tetra-n-butylammonium cation, tributylmethylammonium cation, benzyltriethylammonium cation, benzyltriethylammonium cation, and benzyltributylammonium cation are preferable. . More preferred are tetramethylammonium cation, tetraethylammonium cation, tetra-n-butylammonium cation, tributylmethylammonium cation and benzyltriethylammonium cation.

Examples of the cation raw material include nitrates, sulfates, halide salts, acetates, phosphates, hydroxide salts, etc., preferably nitrates, halide salts, acetates, hydroxide salts. It is. When nitrate is used, it is easy to maintain the tungsten peroxide structure by preventing contamination of impurities and coordination to tungsten.

Preferred forms of the peroxo complex of the present invention include special forms such as a form having no hetero atom such as phosphorus atom and arsenic, a form having no organic ligand, selenium element (Se) and tellurium element (Te). The form which does not have is mentioned. Most preferably, these forms are all applicable. The present invention has important technical significance in that advantageous characteristics such as high catalytic activity can be exhibited without these elements and atomic groups. In such a preferred embodiment, a novel peroxo complex that can be expected to be used in various technical fields can be provided in that a peroxo complex useful as an oxidation catalyst can be easily prepared. This is advantageous. For example, it is considered that it can be used as a precursor for highly dispersing tungsten. Further, it is advantageous in that it becomes a catalyst capable of reducing the use of dangerous reagents and the amount of by-products.
There have been no reports of mononuclear diperoxotungstates that do not use organic ligands. Therefore, a compound that is a mononuclear diperoxotungstate and is identified only by having no organic ligand can also be said to be a novel compound.

To exemplify preferred embodiments of the peroxo complex of the present invention, the mononuclear peroxo ^{_{complex, [WO (O 2) 2}} (H 2 O) Cl] -, [WO (O 2) 2 (H 2 O) F] ⁻ , [WO (O ₂ ) ₂ (H ₂ O) Br] ⁻ , [WO (O ₂ ) ₂ (H ₂ O) I] ^{− and the} like are [{WO (O ₂ ) ₂ ] as a binuclear peroxo complex. } ₄ (μ-O) ₂ ] ^{4- and the} like.
The preferred form of the case where a cationic As the mononuclear peroxo _{complex, (TPA) [WO (O} 2) 2 (H 2 O) Cl] (TPA = [(n-C 3 H 7) 4 N] ⁺ ), (TBA) [WO (O ₂ ) ₂ (H ₂ O) Cl] (TBA = [(n-C ₄ H ₉ ) ₄ N] ⁺ ), (THA) [WO (O ₂ ) ₂ (H ₂ O) Cl] (THA = [(n-C ₆ H ₁₃ ) ₄ N] ⁺ ), (CP) [WO (O ₂ ) ₂ (H ₂ O) Cl] (CP = cetylpyridinium) and the like As peroxo complexes, (TPA) ₃ H [{WO (O ₂ ) ₂ } ₄ (μ-O) ₂ ], (TBA) ₃ H [{WO (O ₂ ) ₂ } ₄ (μ-O) ₂ ] _{, (THA) 3 H [{} WO (O 2) 2} 4 (μ-O) 2], (CP) 3 H [{WO (O 2) 2 _{4 (μ-O) 2],} and the like.

If the three-dimensional structure (anion structure) of the preferred form of the peroxo complex of the present invention is shown, the mononuclear peroxo complex is as shown in FIG. 1, and the binuclear peroxo complex is as shown in FIG. In these drawings, X and Y are the same as described above.
The three-dimensional structure (anion structure) in which the central atom is tungsten is as shown in FIGS. 3 and 4, respectively. These are peroxo complexes synthesized in Examples described later.

A method for producing the peroxo complex of the present invention is described below.
The production method of the mononuclear peroxo complex of the present invention is not particularly limited. For example, the mononuclear peroxo complex can be produced using the above-mentioned raw material having a central atom, a halogen atom raw material, and a cationic raw material. It is also possible to prepare in the system without isolation.
The amount of the halogen atom raw material used is preferably 0.001 to 100,000 parts by mass, more preferably 0, based on 100 parts by mass of the raw material having the central atom from the viewpoint of production, yield, purification, and economy. 0.01 to 50000 parts by mass.
The amount of the cation raw material used is preferably 0.001 to 100,000 parts by weight, more preferably 0.001 parts by weight with respect to 100 parts by weight of the raw material having the central atom, from the viewpoint of production, yield, purification and economy. 01 to 50000 parts by mass.

In addition, the method for producing the binuclear peroxo complex of the present invention is not particularly limited. For example, the binuclear peroxo complex can be produced using the above-mentioned raw material having a central atom and a cationic raw material.
The amount of the cation raw material used is preferably 0.001 to 100,000 parts by weight, more preferably 0.001 parts by weight with respect to 100 parts by weight of the raw material having the central atom, from the viewpoint of production, yield, purification and economy. 01 to 50000 parts by mass.

A method for producing a tungsten peroxo complex, which is one embodiment of the peroxo complex of the present invention, will be described below. However, the present invention is not limited to the following embodiment.

First, among the tungsten peroxo complexes, one of the methods for producing (nC ₃ H ₇ ) ₄ N [WO (O ₂ ) ₂ (H ₂ O) Cl] (I), which is one of mononuclear tungsten peroxo complexes. An example is described.
Add tungstic acid and hydrochloric acid to aqueous hydrogen peroxide and stir. Next, the obtained solution is separated by filtration to remove insolubles, and tetra-n-propylammonium chloride is added and stirred. The formed precipitate is filtered off and washed with water and diethyl ether. The obtained white precipitate is dried, dissolved in acetonitrile, and ether is vapor-diffused into the acetonitrile solution to obtain the compound (I).

Next, among tungsten peroxo complexes, production of (nC ₃ H ₇ ) ₃ H [{WO (O ₂ ) ₂ } ₄ (μ-O) ₂ ] (II), which is one of the binuclear tungsten peroxo complexes. An example of the method will be described.
Mix acetonitrile and aqueous hydrogen peroxide and stir. In this solution, the compound (I) obtained as described above is reacted with silver nitrate. After mixing the ether, the ether is vapor diffused to obtain a colorless square plate-like compound (II).

The concentration of hydrogen peroxide used in the above production method is not particularly limited, and 100% by mass of hydrogen peroxide can also be used. However, in view of easy availability and safe handling, an aqueous solution of 0.1 to 70% by mass is suitable, and more preferably 3 to 65% by mass.

In the above production method, a solvent can be used. The solvent is not particularly limited, but water; primary, secondary, and tertiary monohydric alcohols having 1 to 6 carbon atoms such as methanol, ethanol, n-propanol, isopropanol, and t-butanol; ethylene glycol, propylene glycol Polyhydric alcohols such as glycerin; ethylene oxide such as diethylene glycol and triethylene glycol; oligomers in which propylene oxide is opened; ethers such as diethyl ether, isopropyl ether, dioxane, tetrahydrofuran, and cyclopentyl methyl ether; acetone, methyl ethyl ketone, and methyl isobutyl Ketones such as ketones and acetylacetones; ketones such as ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate Bonates; nitrogen-containing compounds such as methylformamide, dimethylacetamide, nitromethane, acetonitrile, benzonitrile; sulfur compounds such as dimethyl sulfoxide; phosphorus compounds such as phosphate esters such as triethyl phosphate and diethylhexyl phosphate; chloroform, dichloromethane, etc. Halogenated hydrocarbons of the following: aliphatic hydrocarbons such as n-hexane and n-heptane; aromatic hydrocarbons such as toluene and xylene; and alicyclic hydrocarbons such as cyclohexane and cyclopentane. Acetonitrile, benzonitrile, diethyl ether, water, hexane and toluene are preferred.
The amount of the solvent used is preferably 0.0001 to 1000000 parts by mass, more preferably 100 parts by mass with respect to 100 parts by mass of the raw material having the central atom, from the viewpoint of production, yield, purification, economy, and safety. 0.001 to 500000 parts by mass.

The reaction temperature is preferably −20 to 200 ° C., more preferably −10 to 190 ° C. from the viewpoint of production, yield, purification, economy, and safety.
The reaction time is preferably 0.1 to 72 hours, more preferably 0.5 to 60 hours, from the viewpoint of yield, economy, and safety.

The peroxo complex of the present invention can be used as a catalyst for organic reactions such as various oxidation reactions and acid-base reactions, and is particularly preferably used when performing an oxidation reaction or an acid-base reaction in a liquid phase. The catalyst may be in any form as long as it contains a peroxo complex. Specifically, the catalyst is supported on an inorganic carrier such as α-alumina, silica, zirconium oxide, titanium oxide, crystalline, or reacted. It can be used in any form such as being dissolved in a solvent, and can be mixed with other catalysts.

Specific examples of the oxidation reaction are not particularly limited. For example, unsaturated bond oxidation (alkene or alkyne unsaturated double bond or unsaturated triple bond oxidation); hydroxyl group oxidation; heteroatom oxidation (sulfur). Oxidation of atoms and nitrogen atoms); oxidation of saturated hydrocarbon sites; oxidation of aromatic rings; oxidation reactions such as oxidative coupling reactions other than these. By such an oxidation reaction, the oxidizable functional group is oxidized, and an oxidized organic compound is produced.

Specific examples of the acid-base reaction are not particularly limited. For example, esterification reaction; carbon skeleton isomerization reaction; polymerization reaction; addition reaction; ring-opening reaction; elimination reaction; acetalization reaction; ketalization reaction; Aromatic nucleophilic substitution reaction; Aldol reaction; Pinacol transfer reaction; Beckmann transfer reaction; Cannizzaro reaction; Claisen condensation reaction; Darzens condensation reaction; Diels-Alder reaction; Friedel-Crafts reaction; -Koch reaction; Mannich reaction; Michael reaction; Prince reaction; glycosylation reaction; solvolysis reaction; 1,3-dipolar cycloaddition reaction; acid-base reaction other than these.

In the above reaction, the catalyst of the present invention can be used in any reaction method of a gas phase reaction or a liquid phase reaction. For example, an alkene epoxidation reaction using hydrogen peroxide as an oxidizing agent is performed. In the case of carrying out the reaction, it is more preferable to carry out the reaction in a liquid phase in consideration of the reaction activity. The epoxidation reaction of an alkene with an oxidizing agent is exemplified below.

The alkene used in the epoxidation reaction may be acyclic or cyclic. Specifically, ethylene, propylene, 1-butene, 1-hexene, 1-pentene, isoprene, diisobutylene. 1-heptene, 1-octene, 1-nonene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, propylene Terminal olefins such as 1,3-butadiene, styrene, vinyltoluene, divinylbenzene; molecules such as 2-butene, 2-octene, 2-methyl-1-hexene, 2,3-dimethyl-2-butene Inner olefin: cyclopentene, cyclohexene, 1-phenyl-1-cyclohexene, 1 Cyclic olefins such as methyl-1-cyclohexene, cycloheptene, cyclooctene, cyclodecene, cyclopentadiene, cyclodecatriene, cyclooctadiene, dicyclopentadiene, methylenecyclopropane, methylenecyclopentane, methylenecyclohexane, vinylcyclohexane, norbornene, etc. Can be mentioned. As a kind of alkene, 1 type, or 2 or more types can be used. The number of double bond sites present in one molecule may be one, or two or more.

Examples of the alkene used in the epoxidation reaction include —CHO, —COOH, —CN, —COOR, —OR (R represents an alkyl, cycloalkyl, aryl, or arylalkyl substituent), an aromatic group, a halogen, It may have a functional group such as a group, a nitro group, a sulfonic acid group, a carbonyl group, or a hydroxyl group. The number of double bond sites present in one molecule may be one, or two or more. Among these, alkenes having a hydroxyl group are particularly preferred. Examples of the alkene having a hydroxyl group include allyl alcohols and homoallyl alcohols. Examples of homoallylic alcohols include isopropenyl alcohol, 3-butenol, 3-methyl-3-butenol, 3-pentenol, 4-methyl-3-pentenol, 3-hexenol, and 1-methyl-3-hexenol. , 3-heptenol, 3-octenol, 3-nonenol, 3-decenol, 3-undecenol, 3-dodecenol, 3-cyclohexenol, 3-cyclooctenol and the like.

As the oxidizing agent for the epoxidation reaction, hydrogen peroxide is preferable, and practically 0.1 to 70% by mass of an aqueous solution or alcohol solution is preferable, but 100% by mass of hydrogen peroxide can also be used. It is. The amount used is preferably such that the molar ratio of the reaction substrate to hydrogen peroxide (number of moles of reaction substrate / number of moles of hydrogen peroxide) is 100/1 or less, more preferably 10/1 or less. is there. Moreover, it is preferable to set it as 1/100 or more, More preferably, it is 1/50 or more.

The amount of the peroxo complex of the present invention is preferably 0.0001 parts by mass or more and 10,000 parts by mass or less with respect to 100 parts by mass of the reaction substrate. More preferably, it is 0.001 to 5000 parts by mass. Moreover, when using 2 or more types of peroxo complexes as a catalyst, it is preferable to adjust the total mass so that it may become in the said range.

When performing the said epoxidation reaction in a liquid phase, as a solvent, water and / or an organic solvent etc. can be used, for example.
Examples of the organic solvent include primary, secondary, and tertiary monohydric alcohols having 1 to 6 carbon atoms such as methanol, ethanol, n-propanol, isopropanol, and t-butanol; many such as ethylene glycol, propylene glycol, and glycerin. Dihydric alcohol; Diethylene glycol, triethylene glycol and other ethylene oxide and propylene oxide ring-opened oligomers; Ethyl ether, isopropyl ether, dioxane, tetrahydrofuran and other ethers; Acetone, methyl ethyl ketone, methyl isobutyl ketone, acetyl acetone and other ketones; Acetic acid Esters such as methyl, ethyl acetate, propyl acetate, butyl acetate, methyl benzoate, ethyl benzoate, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate; Carbonates such as tylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate; sulfur compounds such as dimethyl sulfoxide; nitrogen compounds such as dimethylformamide, dimethylacetamide, nitromethane, acetonitrile, benzonitrile; triethyl phosphate, diethylhexyl phosphate, etc. Phosphorus compounds such as phosphate esters; Halogenated hydrocarbons such as chloroform and dichloromethane; Aliphatic hydrocarbons such as n-hexane and n-heptane; Aromatic hydrocarbons such as toluene and xylene; Alicyclic rings such as cyclohexane and cyclopentane Formula hydrocarbons and the like. One or two or more organic solvents can be used.

Among the above solvents, water, alcohols having 1 to 4 carbon atoms, dichloromethane, heptane, acetonitrile, benzonitrile, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, nitromethane, ethyl acetate, butyl acetate, methyl benzoate, ethyl benzoate, It is preferable to use dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate, ethylene carbonate, propylene carbonate, or a mixture thereof. When the olefin compound is a liquid under the reaction conditions, it is possible to carry out the reaction neat without using the solvent. In the present invention, it is possible to make the catalyst heterogeneous by selecting the counter cation species of the peroxo complex and the solvent. In this case, for example, at least one of quaternary alkyl ammonium and proton is selected as a counter cation, and nitromethane, ethyl acetate, butyl acetate, methyl benzoate, ethyl benzoate, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, phthalate More preferably, at least one solvent selected from dioctyl acid, ethylene carbonate, and propylene carbonate is used.

The epoxidation reaction is preferably carried out in a neutral to acidic solution, and an acidic substance may be added to the reaction system for pH adjustment. Examples of the acidic substance include Bronsted acid and Lewis acid, and one kind or two or more kinds can be used. Examples of Bronsted acids include mineral acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, and boric acid, organic acids such as acetic acid, benzoic acid, formic acid, and trifluoromethanesulfonic acid; zeolites, mixed oxides, and the like. Inorganic acids are preferred. As the Lewis acid, aluminum chloride, ferric chloride, boron chloride compounds, stannic chloride, antimony fluoride, zinc chloride, titanium compounds, zeolites, composite oxides and the like are suitable. In addition, inorganic and / or organic acid salts can also be used.

In the epoxidation reaction, a phase transfer catalyst and a surfactant can coexist. It is also possible to carry out the reaction under light irradiation.

The reaction temperature of the epoxidation reaction in the liquid phase reaction is preferably 0 ° C. or higher, more preferably 15 ° C. or higher. Moreover, 100 degrees C or less is preferable, More preferably, it is 80 degrees C or less. The reaction time is preferably 1 minute or longer and 150 hours or shorter. More preferably, it is 3 minutes or more and 48 hours or less. The reaction pressure is not particularly limited, but is preferably 2.03 MPa or less. More preferably, it is 1.02 MPa or less, and the reaction can be carried out under reduced pressure.

As described above, the peroxo complex of the present invention is preferably used as an oxidation catalyst. In general, any mononuclear peroxo complex or binuclear peroxo complex can be applied as an oxidation catalyst as long as it is an oxidation reaction to which a peroxo complex can be applied.
Among various oxidation catalysts, the peroxo complex of the present invention is preferably used as an alkene epoxidation reaction catalyst as described above. The epoxidation reaction is one of basic reactions in industrial organic chemistry, and the epoxy compound obtained by the epoxidation reaction is a useful compound in various industrial chemical applications.

For example, as an example of production of an industrial product having an epoxy compound as an intermediate compound, ethylene oxide is converted to ethylene glycol or polyethylene glycol, and alcohol is alkoxylated with propylene oxide to produce polypropylene polyether or the like. Polyether polyols are formed. Industrial products produced in this way are consumed in large quantities in the production of polyurethanes and synthetic elastomers. Epoxy compounds are also important intermediates in the production of alkylene glycols and alkanolamines such as propylene glycol and dipropylene glycol, which are one of important industrial products as a raw material for solvents and surfactants. Furthermore, a compound having a functional group other than an epoxy group in the molecule can be used as an intermediate capable of synthesizing various derivatives utilizing the reactivity of these functional groups, for example, glycidol in which the double bond of allyl alcohol is epoxidized. Is a compound useful as a raw material for pharmaceuticals and intermediates thereof, paints, adhesives, semiconductor UV curing agents, and the like, such as glycidyl ether, glycidyl ester, glycerin ether, glycerin ester, and dihydroxypropylamine.

In the present invention, novel mononuclear peroxo complexes and binuclear peroxo complexes were obtained. The peroxo complex exhibits high activity in oxidation reactions without having heteroatoms, organic ligands, and special elements, and is suitable as an oxidation catalyst, particularly as an epoxidation reaction catalyst for unsaturated bond-containing compounds such as alkenes. Can be used.

It is a figure which shows the stereostructure (anion structure) of the preferable form of the mononuclear peroxo complex of this invention. It is a figure which shows the stereostructure (anion structure) of the preferable form of the binuclear peroxo complex of this invention. It is a figure which shows the stereostructure (anion structure) of the preferable form of the mononuclear peroxo complex which made the central atom tungsten. It is a figure which shows the stereostructure (anion structure) of the preferable form of the binuclear peroxo complex which made the central atom tungsten. It is a figure which shows IR spectrum ((a), (b), respectively) of compound (I) and compound (II). It is a figure which shows the Raman spectrum ((a), (b), respectively) of compound (I) and compound (II). It is a graph which shows the reaction rate of compound (II). It is a graph which shows TOF of the epoxidation reaction of cyclooctene. It is a graph which shows the correlation with TOF and the chemical shift of ¹⁸³ W-NMR. It is a figure which shows ¹⁸³ W-NMR spectrum ((a), (b), respectively) of compound (I) and compound (II). It is a figure which shows the positive ion CSI-MS spectrum (upper part) and the calculated pattern (lower part) of compound (I).

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. “TPA” means “tetra-n-propylammonium”.

Example 1 Synthesis of (TPA) [WO (O ₂ ) ₂ (H ₂ O) Cl] (I) Tungstic acid (H ₂ WO ₄ , 1.7 mmol) and 12M hydrochloric acid (20 mmol) were peroxidized to 15%. In addition to hydrogen water (42 mmol), tetra-n-propylammonium chloride (TPA · Cl, 30 mmol) was added to the hydrogen peroxide solution to obtain a crude product. Compound (I) was synthesized by vapor diffusion of ether into the acetonitrile solution at 0 ° C.
Ether was added to an acetonitrile solution containing compound (I) and hydrogen peroxide, and ether vapor was further diffused to obtain colorless square plate crystals suitable for X-ray structural analysis. The anion structure of compound (I) is shown in FIG. The anion has a seven-coordinate pentagonal bipyramidal structure, and two peroxo ligands and a Cl ligand are located in the equatorial position. The BVS values of O1 and O6 located in the axial position were 0.28 and 1.90, respectively, and were estimated to be aco and oxo, respectively.
From elemental analysis, Cl was present in Compound (I), and TPA: W: Cl = 1: 1: 1. Bands attributed to the peroxo ligand were confirmed in the IR spectrum (851, 837, 643, 554 cm ⁻¹ ) and the Raman spectrum (860, 648, 563 cm ⁻¹ ) ((a) of FIG. 5 and FIG. 6). ). An IR absorption band derived from ν (O—H) of the acoligand was confirmed at 3636 cm ⁻¹ . Bands belonging to ν (W—Cl) were confirmed at 336 cm ⁻¹ and 319 cm ⁻¹ in the IR spectrum and the Raman spectrum, respectively. These results were consistent with the crystal structure.
In the stoichiometric oxidation reaction of triphenylphosphine with compound (I), 2 equivalents of triphenylphosphine oxide were formed, which was consistent with the presence of 2 equivalents of peroxo in compound (I).
In the ¹⁸³ W-NMR spectrum of the compound (I), a single signal could be confirmed at −407.3 ppm (Δν _1/2 = 4.4 Hz) ((a) in FIG. 10). Further, in the positive ion CSI-MS spectrum, [(TPA) ₂ WO (O ₂ ) ₂ Cl] ⁺ was confirmed, and it was stable in a dissolved state (FIG. 11).
Table 1 shows crystal data of the compound (I). In addition, the analysis results are shown below. UV / Vis (CH ₃ CN) λ _max (ε) 269.0 nm (1270 (mol of W) ⁻¹ dm ³ cm ⁻¹ ); IR (KCl): 3636, 1174, 1039, 975, 875, 851, 837 , 755, 643, 554, 336, 323 cm ⁻¹ ; Raman: v = 1146, 1133, 1046, 985, 944, 930, 881, 860, 783, 762, 648, 621, 563, 378, 319 cm ⁻¹ ; MS (+) (CSI, CH ₃ CN): m / z: 672 [(TPA) ₂ WO (O ₂ ) ₂ Cl]; Elemental analysis calcd (%) for C ₁₂ H ₃₀ Cl ₁ N ₁ O ₆ W ₁ ( _{(TPA) [WO (O 2} ) 2 (H 2 O) Cl]): C28.62, H6.00, N2.78, Cl7.04, W36.50; ound: C28.54, H6.10, N2.79, Cl7.17, W36.74.

Example 2 Synthesis of (TPA) ₃ H [{WO (O ₂ ) ₂ } ₄ (μ-O) ₂ ] (II) 30% hydrogen peroxide (0.5 mL) was added to acetonitrile (5 mL). In the mixed solution of the hydrogen peroxide solution, the compound (I) (1.0 mmol) obtained in Example 1 and silver nitrate (1.0 mmol) were reacted. After mixing ether with the reaction solution, vapor diffusion of ether was further performed to obtain a colorless square plate crystal compound (II) suitable for X-ray structural analysis.
The anion (FIG. 4) of compound (II) is composed of two [{WO (O ₂ ) ₂ } ₂ (μ-O)] ^2- units. Binuclear peroxotungstate [{WO (O ₂ ) ₂ } ₂ (μ-O)] ^2- and [{WO (O ₂ ) ₂ } ₂ (μ-O ₂ )] ^2- Are cross-linked. In contrast, in compound (II), peroxo bridges tungsten between units. Since three TPAs were confirmed in the crystal structure and elemental analysis was also TPA: W = 3: 4, the molecular formula was (TPA) ₃ H [{WO (O ₂ ) ₂ } ₄ (μ-O) ₂ It was estimated. Since the BVS values of O21 and O22 were 1.77 and 1.55, respectively, it was considered that H ⁺ existed between O21 and O22 and was hydrogen-bonded. In addition, the anion structure of compound (II) (a structure in which H ⁺ is present between O21 and O22 [{WO (O ₂ ) ₂ } ₄ (μ-O) ₂ H] ³⁻ (A), O21 and O22 When a quantum calculation of a structure [{WO (O ₂ ) ₂ } ₄ (μ-O) ₂ ] ⁴⁻ (B)) in which H ⁺ does not exist in between is performed, the calculation structure of A agrees well with the experimental value. The error in the bond length was within 0.072 mm, but the error in the bond length in the case of B was within 0.121 mm. The error of the bond angles of W1-O21-W3 and W2-O22-W4 was within 1.90 ° in the case of A, but was within 16.48 ° in the case of B. These results supported the presence of hydrogen between O21 and O22. (Tables 4-6)
Bands attributed to the peroxo ligand were confirmed in the IR spectrum (844, 573, 511 cm ⁻¹ ) and the Raman spectrum (859, 580, 526 cm ⁻¹ ) (FIG. 5 and FIG. 6B). Stoichiometric oxidation of triphenylphosphine with compound (II) yielded 8 equivalents of triphenylphosphine oxide. This was consistent with the presence of 8 equivalents of peroxo in the molecule. Further, in the ¹⁸³ W-NMR of the compound (II), one signal appears at −565.6 ppm (Δν _1/2 = 1.6 Hz), suggesting that the tungsten 4 nucleus structure is retained in the dissolved state. It was.
Table 1 shows crystal data of the compound (II). In addition, the analysis results are shown below. UV / Vis (CH ₃ CN) λ _max (ε) 269.0 nm (1270 (mol of W) ⁻¹ dm ³ cm ⁻¹ ); IR (KCl): 1038, 981, 967, 844, 755, 707, 670 , 642, 585, 573, 511, 377 cm ⁻¹ ; Raman: v = 1136, 1105, 1036, 973, 859, 580, 526, 309 cm ⁻¹ ; elemental analysis calcd (%) for C ₃₆ H ₈₅ N ₃ O _{22 W 4 ((TPA) 3 H} [{WO (O 2) 2} 4 (μ-O) 2]): C26.25, H5.20, N2.55, W44.64; found: C26.01, H5 .31, N2.53, Cl 7.17, W44.45.
This compound can also be synthesized by the following steps.
H ₂ WO ₄ (4 mmol) was added to 30% aqueous hydrogen peroxide (4 mL) and stirred at room temperature for 90 minutes. 1M TPAOH solution (4 mL) was added and stirred, and the resulting solid was filtered. The filtrate was concentrated to about 2 mL at room temperature under reduced pressure, this solution was added dropwise to diethyl ether / isopropanol = 80/20 (mL / mL), and the resulting solid was filtered and washed with diethyl ether. This solid (50 mg) was dissolved in acetonitrile (0.8 mL), and ether vapor was further diffused at 293 K to obtain (TPA) ₂ [{WO (O ₂ ) ₂ } ₂ (μ-O)]. (TPA) ₂ [{WO (O ₂ ) ₂ } ₂ (μ-O)] (58 μmol) and 70% nitric acid (100 μmol) in acetonitrile (0.5 mL) and 30% hydrogen peroxide (0.05 mL) Was dissolved in a dissolved solution. Diethyl ether (0.5 mL) was added, and ether vapor was further diffused at 277 K to obtain colorless square plate crystal compound (II).

Example 3 Epoxidation The catalytic activities of Compound (I) and Compound (II) were examined as follows. When cyclooctene was epoxidized using Compound (I) with hydrogen peroxide as an oxidizing agent, the reaction proceeded fairly slowly. When compound (II) was used as a catalyst, cyclooctene was efficiently oxidized, and the corresponding epoxide was obtained in 98% yield in 30 minutes (FIG. 7). The epoxidation reaction of cyclooctene using hydrogen peroxide as an oxidizing agent was performed. Even when cyclooctene was oxidized using compound (II) under stoichiometric conditions (substrate: hydrogen peroxide = 1: 1), the corresponding epoxide was obtained in high yield (yield 86%, reaction time 4). time).
Of the various solvents studied, acetonitrile was the best.

Example 4
Using compound (II) as a catalyst, the substrate applicability of the oxidation reaction with hydrogen peroxide was examined as follows (Table 3). The reaction proceeded efficiently at room temperature, and cyclic and internal alkenes were oxidized to the corresponding epoxides in high yield and high selectivity (Table 3, entries 1-8). Dicyclopentadiene having two C═C bonds in the molecule was also efficiently oxidized, and the corresponding diepoxide was obtained with high yield and high selectivity. Compound (II) could be recovered by adding an excess amount of ether. The recovered compound (II) could be reused without a significant decrease in activity. (Compound (II) (20 μmol), cyclooctene (4 mmol), 30% hydrogen peroxide (4 mmol), acetonitrile (24 mL) under conditions of 6 hours, product: yield 92%, reuse (first time): Yield was 88%.)
The sulfide was also selectively oxidized to the corresponding sulfoxide (entries 10, 11). Oxidation of secondary amines with 2 equivalents of hydrogen peroxide gave the corresponding nitrones in high yield and high selectivity (entry 12). Oxidation of aniline with 2 equivalents of hydrogen peroxide gave the corresponding nitrosobenzene in high yield and high selectivity (entry 13). The excess oxidation product, nitrobenzene, was hardly formed. Triethylsilane was also efficiently oxidized to the corresponding silanol (entry 14).
20 mmol of cyclooctene was also efficiently oxidized by compound (II) to give the corresponding epoxide in 86% yield. At this time, TON (turnover number) reached 1720. This value _{is, [(n-C 6 H} 13) 4 N] 2 [{WO (O 2) 2} 2 (μ-O)] (600), Na 2 WO 4 / NH 2 CH 2 PO 3 H 2 _{/ [CH 3 (n-C} 8 H 17) 3 n] HSO 4 (490), PW 12 O 40 / C 3 n 2 H 3 (CH 2) 3 SiO 3 / SiO 2 (648) or the like of the catalyst system of It is much larger than the value. _{Na 2 WO 4 / H 2 WO} 4 / CH 3 (n-C 8 H 17) 3 NCl / ClCH 2 COOH (1800) and _{[WO (O 2) (CPHA} ) 2] / NaHCO 3 (7200; CPHA = N Although it does not reach the value of -cinnamyl-N-phenylhydroxamate), these require the addition of a toxic acid or a large amount of base.

(Example 5)
The reaction rate of the catalyst system obtained in Example 2 was examined. The reaction rate was linearly dependent on the concentrations of Compound (II) and cyclooctene, and was not dependent on the concentration of hydrogen peroxide (FIG. 7). From these results, it became clear that the compound (II) is an active species, and the reaction between the compound (II) and the substrate is rate-limiting.
The epoxidation reaction of cyclooctene by compound (II) proceeded efficiently, and the initial TOF (turnover frequency) reached 314 (hours) ⁻¹ . This value is [ZO ₄ {WO (O ₂ ) ₂ } ₄ ] ^n- (Z = P, As), [RR′ZO ₄ {WO (O ₂ ) ₂ } ₂ ] ^n- (Z = P, Se, As), [{WO (O ₂ ) ₂ } ₂ (μ-O)] is the largest among the catalysts (FIG. 8). The activity of these catalysts has been shown to correlate with the chemical shift of ¹⁸³ W-NMR. The same tendency was confirmed also about compound (II) (FIG. 9). The electron density was compared by quantum calculation. Compound (II) has the largest NO4 charge of O4. This indicated that Compound (II) has a strong electrophilicity.

A specific description of FIGS. 7 to 11 will be given below.
FIG. 7 shows the dependence of the reaction rate on the concentrations of (a) compound (II), (b) cyclooctene, and (c) hydrogen peroxide. Reaction conditions for (a): Compound (II) (0.23-1.44 mM), cyclooctene (0.14 M), hydrogen peroxide (0.14 M), water (0.56 M), acetonitrile (7 mL), 305K, slope = 1.02 (R ² = 0.99). Reaction conditions for (b): Compound (II) (0.36 mM), cyclooctene (0.04-0.43 M), hydrogen peroxide (0.14 M), water (0.56 M), acetonitrile (7 mL), 305K, slope = 1.11 (R ² = 0.99). Reaction conditions for (c): Compound (II) (0.36 mM), cyclooctene (0.14 M), hydrogen peroxide (0.04-0.43 M), water (0.56 M), acetonitrile (7 mL), 305K.

FIG. 8 shows the TOF of various catalysts in the epoxidation reaction of cyclooctene using hydrogen peroxide. Reaction conditions: catalyst (W: 1 mol%), cyclooctene (5 mmol), 30% hydrogen peroxide (1 mmol), acetonitrile (6 mL), 305K. TOF was measured from the reaction at a low concentration of hydrogen peroxide (≦ 10%). The abbreviations of peroxotungstate are as follows. SeW2: (TBA) ₂ [SeO ₂ {WO (O ₂ ) ₂ } ₂ ], AsW4: (THA) ₃ [AsO ₄ {WO (O ₂ ) ₂ } ₄ ], SW2: (TBA) ₂ [SO ₄ { WO (O ₂ ) ₂ } ₂ ], PW4: (THA) ₃ [PO ₄ {WO (O ₂ ) ₂ } ₄ ], AsW2: (TBA) ₂ [HAsO ₄ {WO (O ₂ ) ₂ }], PW ₂ : (TBA) ₂ [HPO ₄ {WO (O ₂ ) ₂ } ₂ ], W2: (TBA) ₂ [{WO (O ₂ ) ₂ } ₂ (μ-O)], SiW ₂ : (TBA) ₂ [Ph _{2 SiO 2 {WO (O 2} ) 2} 2].

FIG. 9 shows the correlation between TOF and ¹⁸³ W-NMR chemical shift. The reaction conditions are the same as in FIG.
FIG. 10 shows ¹⁸³ W-NMR spectra of (a) compound (I) (0.57 M, in CH ₃ CN, 298 K) and (b) compound (II) (0.061 M, in CD ₃ CN, 253 K). .
FIG. 11 shows a positive ion CSI-MS spectrum (CH ₃ CN; m / z = 500-1500) of compound (I). Positive ion CSI-MS spectrum (m / z = 660-690) of the calculated pattern (bottom) of compound (I) (top) and [(TPA) ₂ WO (O ₂ ) Cl] ⁺ .

Each table shows the following.
Table 1: Crystal data of compounds (I) and (II) Table 2: Bond lengths (angstroms) and angles (°) of compounds (I) and (II)
Table 3: Oxidation of various alkenes and amines using compound (II) as a catalyst and hydrogen peroxide Table 4: Bond length of calculated structure and crystal structure (angstrom) in compound (II)
Table 5: Cartesian coordinates of the calculated structure, [{WO (O ₂ ) ₂ } ₄ (μ-O) ₂ H] ^3-
Table 6: Cartesian coordinates of the calculated structure, [{WO (O ₂ ) ₂ } ₄ (μ-O) ₂ ] ⁴⁻

Each comment in Table 3 is as follows.
Reaction conditions: Compound (II) (2.5 μmol), substrate (1 mmol), 30% hydrogen peroxide (1 mmol), acetonitrile (6 mL), air [b]: Compound (II) (10 μmol), 30% peroxidation Hydrogen (1.5 mmol)
[C]: Compound (II) (5 μmol), 30% hydrogen peroxide (1.5 mmol)
[D]: Compound (II) (10 μmol)
[E]: Compound (II) (20 μmol), 30% hydrogen peroxide (1.5 mmol)
[F]: Compound (II) (10 μmol), substrate (0.5 mmol), 30% hydrogen peroxide (1.5 mmol)
[G]: Compound (II) (5 μmol), 30% hydrogen peroxide (2 mmol)
[H]: Compound (II) (20 μmol), substrate (5 mmol)
[I]: Compound (II) (5 μmol)
[J]: Compound (II) (0.6 μmol)

In the above examples, novel mononuclear peroxo complexes and binuclear peroxo complexes were obtained. In addition, both the mononuclear peroxo complex and the binuclear peroxo complex were shown to have high catalytic activity in the alkene epoxidation reaction and the like, and in particular, the binuclear peroxo complex was shown to have superior catalytic activity.
In the above examples, the central atom has been demonstrated in the form of tungsten. However, if selected from transition metal elements belonging to Group 5 and Group 6, they are in the same or similar / adjacent groups. If it is an element to which it belongs, the same catalytic action can be exhibited. That is, by using a peroxo complex having a transition metal element belonging to Group 5 and Group 6 as a central atom, the mechanism of action of the complex exhibiting high catalytic activity in the alkene epoxidation reaction is the present invention. This is the same in all cases where the peroxo complexes of are used.
Therefore, it can be said from the results of the above-described embodiments that the present invention can be applied in the entire technical scope of the present invention and in various forms disclosed in the present specification, and can exhibit advantageous effects.

Claims (8)

A peroxo complex in which a peroxo group is coordinated to a central atom,
The central atom is at least one transition metal element selected from Group 5 and Group 6 of the Periodic Table;
The peroxo complex is a mononuclear peroxo complex composed of one central atom, has a structure in which a plurality of peroxo groups are coordinated to the central atom as a bidentate ligand, and a halogen atom is coordinated to the central atom. A peroxo complex having a coordinated structure. A peroxo complex in which a peroxo group is coordinated to a central atom,
The central atom is at least one transition metal element selected from Group 5 and Group 6 of the Periodic Table;
The peroxo complex is a binuclear peroxo complex composed of a plurality of central atoms, has a structure in which a plurality of peroxo groups are coordinated to the central atom as a bidentate ligand, and one of the oxygen atoms of the peroxo group is the other. A peroxo complex having a structure in which central atoms are bonded to each other only by oxygen atoms. The peroxo complex according to claim 1 or 2, wherein the central atom is tungsten and / or molybdenum. The peroxo complex according to claim 1, wherein the central atom is tungsten. The peroxo complex according to any one of claims 1 to 4, wherein the peroxo complex is used as an oxidation catalyst. The peroxo complex according to any one of claims 1 to 5, wherein the peroxo complex is used as a catalyst for an epoxidation reaction of an alkene. A structure in which two peroxo groups are coordinated to a central atom as a bidentate ligand, and further has a structure in which two oxygen atoms and one halogen atom are coordinated to the central atom. 2. The peroxo complex according to 1. The following general formula (1), general formula (2), general formula (1 '), or general formula (2'):
[XO (O ₂ ) ₂ (H ₂ O) Y] ⁻     (1)
[XO (O ₂ ) ₂ Y] ^2-     (2)
A [XO (O ₂ ) ₂ (H ₂ O) Y] (1 ')
A ₂ [XO (O ₂ ) ₂ Y] (2 ')
(In the above general formula, X represents a central atom. Y represents a halogen atom. A represents a cation. When there are a plurality of A, A may be the same or different. The peroxo complex according to claim 1, which is represented by:

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