JP2010046560A - Method for preparing heteropolyoxometallate compound - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new method for producing a heteropolyoxometallate compound having a di-substituted Keggin-type structure, and a catalytic reaction using the heteropolyoxometallate compound. <P>SOLUTION: The method for producing the heteropolyoxometallate compound having the di-substituted Keggin-type structure comprises the steps of: introducing at least one element selected from group 3 elements to group 13 elements into a heteropolyoxometallate compound having a di-lacunary Keggin-type structure represented by formula (2): [XW<SB>10</SB>O<SB>36</SB>]<SP>8-</SP>obtained by using a heteropolyoxometallate compound having a mono-lacunary Keggin-type structure, and represented by formula (1): [β<SB>2</SB>-XW<SB>11</SB>O<SB>39</SB>]<SP>8-</SP>obtained by reacting a compound containing one element selected from Si and Ge with a W-containing compound under a condition of pH6-7 as a precursor. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention is a method for producing a heteropolyoxometalate compound having a disubstituted Keggin structure, which is prepared by the formula (1) [β ₂ -XW ₁₁ O ₃₉ ] ⁸⁻ prepared at pH = 6-7 (wherein X as a heteroatom represents a kind of element selected from Si or Ge, W as a polyatom represents tungsten, and O represents oxygen. A precursor compound (hereinafter referred to as a single-deficient POM compound). (XW ₁₀ O ₃₆ ] ⁸⁻ (wherein X represents a heteroatom represents a kind of element selected from Si or Ge, and W as a polyatom is Heteropolyoxometalate compound having a two-deficient Keggin structure represented by tungsten (O represents oxygen) (hereinafter referred to as a two-deficient POM compound) A heteropolyoxometalate compound having a disubstituted kegin structure (hereinafter sometimes referred to as a disubstituted POM compound), wherein at least one element selected from Group 3 to 13 is introduced into It is related with the manufacturing method.

  The heteropolyoxometalate compound expresses acid properties and / or oxidation properties and the like from its unique structure, and can be used as various catalysts, carriers, and the like (see Patent Document 1, Non-Patent Documents 1 to 3).

When used as a solid catalyst or a support, the larger the specific surface area, the higher the activity per unit weight. Therefore, a higher specific surface area is desired. It is known that a compound having a pore structure exhibits a unique catalytic performance due to reaction substrate selectivity due to steric restriction by the pore structure and product structure selectivity. Has been developed.
The heteropolyoxometalate compound having the one-deficient Keggin structure is
A. Tze, G.M. Herve, “Inorganic Synths” (USA), 1990, 270, p.85.
N. H. NSouli, B.M. S. Bassil, M.M. H. Dickman, U.D. Kortz, B.M. Keita, L .; Nadjo, “Inorg. Chem.” (USA), 2006, 45, p. 3858.
In general, it was generally prepared by setting the pH to 5 to 6, but the yield and purity of the compound and the formula (2) derived from the compound are represented by Di-substitution in which the yield and purity of a heteropolyoxometalate compound having a two-deficient Keggin structure is often reduced, resulting in synthesis using a heteropolyoxometalate compound having a two-deficient Keggin structure as a raw material There has been a problem that the yield and purity of the heteropolyoxometalate compound having a Keggin structure is lowered.

International Publication No. 02/072257 T.A. Okuhara, “Chem. Rev.” (USA), 2002, 102, p. 3641 T.A. Nakajo, A .; Miyaji, K. et al. Tsuji, “Fine Chemical” (Japan), 2007, Vol. 36, No. 11, p. 30 N. Mizuno, M.M. Misono, “Chem. Rev.” (USA), 1998, Vol. 98, p. 199

  An object of the present invention is to provide a novel method for producing a heteropolyoxometalate compound having a disubstituted Keggin structure, and to provide a catalytic reaction using the compound.

As a result of intensive studies on a method for producing a heteropolyoxometalate compound having a disubstituted Keggin structure, the present inventors usually hydrolyze a compound containing a hetero element and a compound containing a poly element under high pH conditions. In the production of heteropolyoxometalate compounds that have properties and are produced at low pH, conventional single-deficient POM compounds that have been produced in a pH range of 5 to 6 can be used in a pH range of 6 to 7 that is a high pH condition. Prepared formula (1) [β ₂ -XW ₁₁ O ₃₉ ] ^8- (wherein X as a heteroatom represents a kind of element selected from Si or Ge, W as a polyatom represents tungsten, O Represents a heteropolyoxometalate compound having a single-deficient Keggin structure represented by a high yield and high purity. It has been found that when a compound is used as a precursor, a disubstituted POM compound having excellent catalytic performance and a unique pore structure can be obtained, and the present invention has been completed.

That is, as means for solving the above-described problems, the following method for producing a disubstituted POM compound using a heteropolyoxometalate compound having a two-deficient Keggin structure having a one-deficient POM compound as a precursor, and the disubstituted POM A catalyst comprising the compound was invented.
(I) A method for producing a heteropolyoxometalate compound having a disubstituted Keggin structure,
By a method for producing a heteropolyoxometalate compound having a one-deficient Keggin structure, wherein a compound containing one element selected from Si or Ge and a compound containing W are reacted under conditions of pH 6-7 Obtained formula (1) [[β ₂ -XW ₁₁ O ₃₉ ] ⁸⁻ (wherein X as a heteroatom represents a kind of element selected from Si or Ge, and W as a polyatom represents tungsten, O represents oxygen.) Formula (2) [XW ₁₀ O ₃₆ ] ⁸⁻ (wherein a heteroatom is obtained using a heteropolyoxometalate compound having a one-deficient Keggin structure represented by the following formula: X represents a kind of element selected from Si or Ge, W as a poly atom represents tungsten, and O represents oxygen.) A heteropolyoxometalate compound having a disubstituted Keggin structure characterized by introducing at least one element selected from Group 3 to Group 13 into a heteropolyoxometalate compound having a two-deficient Keggin structure represented Manufacturing method.
(II) The heteropolyoxometalate compound having a two-deficient Keggin structure described in the formula (2) is characterized in that X is Si and a γ-body two-deficient structure. A method for producing a heteropolyoxometalate compound having a substituted Keggin structure.
(III) The method for producing a heteropolyoxometalate compound having a disubstituted Keggin structure according to (I) or (II), wherein the element is Zr, Hf, V, W, Mo, or Cu.
(IV) A heterogeneous catalyst comprising a heteropolyoxometalate compound having a Keggin structure obtained by the production method described in (I) to (III).
(V) A heteropolymetalate compound having a Keggin structure obtained by the production method according to (I) to (III), wherein the compound has a Keggin structure having a tetravalent valence. A heteropolyoxometalate compound comprising an anion and four cations selected from a quaternary alkylammonium cation, an alkali metal cation, an alkaline earth metal cation and / or a proton, and having a structurally limited microporous structure.

  The novel production method of the present invention is such that a disubstituted POM compound using as a precursor a two-deficient POM compound obtained from a one-deficient POM compound obtained under specific conditions exhibits excellent catalytic performance, Since it has a limited micropore structure, it is expected to have unique reactivity due to its unique structure, and at the same time, it is expected to be applied to materials such as separation membranes that make use of the characteristics of micropores.

  The one-deficient POM compound represented by the formula (1) serving as a precursor reacts a compound containing one kind of element selected from Si or Ge with a compound containing W as a poly atom under the condition of pH 6-7. Can be obtained.

  As a raw material used for the preparation of the one-deficient POM compound, a compound containing both the hetero atom and the poly atom and the atom and oxygen is preferable, an alkali metal salt, an alkaline earth metal salt, and an oxide are more preferable. Specifically, sodium tungstate, potassium tungstate, cesium tungstate, calcium tungstate, barium tungstate, tungstic acid, tungsten oxide, silicic acid, sodium silicate, potassium silicate, cesium silicate, calcium silicate, barium silicate, silicon oxide And germanium oxide.

  After mixing in an acidic aqueous solution so that W, which is a polyelement, is 11 moles per mole of the heteroelement using the raw material, the pH is adjusted to 6-7, and further neutral such as alkali metal chlorides. By adding the alkali metal salt, an alkali metal salt of a single deficient POM compound can be obtained.

The two-deficient POM compound represented by the formula (2) is prepared by dissolving the alkali metal salt of the one-deficient POM compound in water and adjusting the pH of the solution to 8 to 10 to show neutral alkali metal salt such as alkali metal By adding a chloride or the like, an alkali metal salt of the two-deficient POM compound can be obtained. Further, when the pH is adjusted to 8.8 to 9.1, a two-deficient POM compound having a γ-type structure ([γ-XW ₁₀ O ₃₆ ] ⁸⁻ ) can be obtained.

  A disubstituted POM compound obtained by introducing a total of two kinds of one or two kinds of atoms selected from Group 3 to 13 into the deficient site of the two deficient structure is obtained, preferably Sc, Y, Lanthanoid, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Au, Ag, Zn, Al, In, more preferably lanthanoid, Ti, Zr, Hf, V, Mo, W, Mn, Fe, Ru, Co, Ni, Cu, Al, most preferably Zr, Hf, V, W, Mo, Cu. A disubstituted POM compound obtained by introducing two kinds of atoms selected from Zr, Hf, V, W, Mo, and Cu is more preferable. When the structure of the two-deficient POM compound used is a γ-type, it becomes a shared edge type in which the introduced adjacent metal is cross-linked with two or more oxygen, nitrogen, or the like. The disubstituted POM compound may be a monomer or a multimer. In the case of a multimer, the monomer structure site of the anion skeleton is defined as one unit. For example, if the valence is octavalent in the structure of the dimer, the valence of the disubstituted POM compound is 4 Suppose that it is worth.

  The disubstituted POM compound is a kind of atom in which the hetero atom is selected from Si or Ge, and one or two kinds of atoms in which the poly atom is selected from 10 W and Zr, Hf, V, W, Mo, Cu. Is preferably a POM having a Keggin-type structure consisting of a total of two, and most preferably a disubstituted POM compound having two kinds of atoms selected from Zr, Hf, V, W, and Cu.

  The disubstituted POM compound is a compound containing at least one element selected from Group 3 to 13 after adjusting the pH of the solution after dissolving the alkali metal salt of the two-deficient POM compound in an aqueous medium. Can be obtained by adding The pH of the solution is appropriately determined depending on the metal to be introduced. For example, in the case of Zr, pH = 2.3, in the case of Hf, pH = 2.6, in the case of V, pH = 2 or less, W or Mo In this case, it is preferable that pH = 2 or less, and in the case of Cu, pH = 6.3. As the compound containing the introduced element, alkali metal salts, alkaline earth metal salts, halides, oxides, acetates, oxalates, and the like are more preferable. Specifically, zirconium oxychloride, hafnium oxychloride, metavanadine. Sodium oxide, metavanadate, vanadium oxide, sodium tungstate, potassium tungstate, cesium tungstate, calcium tungstate, barium tungstate, tungstic acid, tungsten oxide, tungsten chloride, sodium molybdate, potassium molybdate, cesium molybdate, Examples include calcium molybdate, barium molybdate, molybdic acid, molybdenum oxide, molybdenum chloride, copper chloride, copper acetate, and copper oxalate.

  Further, when sodium azide or the like is allowed to coexist during the preparation of the disubstituted POM compound, the disubstituted POM compound in which nitrogen (azide group) is introduced into the intermetallic crosslinking site can be obtained.

  The disubstituted POM compound 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.

  Specific examples of the oxidation reaction are not particularly limited. For example, <1> oxidation of unsaturated bond (oxidation of unsaturated double bond or unsaturated triple bond of alkene or alkyne), <2> oxidation of hydroxyl group, < 3> Oxidation of heteroatoms (oxidation of sulfur atoms, nitrogen atoms, etc.), <4> Oxidation of saturated hydrocarbon moieties, <5> Oxidation of aromatic rings, <6> Oxidation cups other than these <1> to <5> Examples thereof include an oxidation reaction such as a ring reaction. 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, <7> esterification reaction, <8> carbon skeleton isomerization reaction, <9> polymerization reaction, <10> addition reaction, <11> ring-opening reaction <12> elimination reaction, <13> acetalization reaction, <14> ketalization reaction, <15> aromatic electrophilic substitution reaction, <16> aromatic nucleophilic substitution reaction, <17> aldol reaction, <18 > Pinacol transfer reaction, <19> Beckmann transfer reaction, <20> Cannizzaro reaction, <21> Claisen condensation reaction, <22> Darzens condensation reaction, <23> Diels-Alder reaction, <24> Friedel-Crafts reaction, <25 > Fries transfer reaction, <26> Gatterman-Koch reaction, <27> Mannich reaction, <28> Michael reaction, <29> Prinse reaction, <30> Glycosylation reaction, <31 Solvolysis reaction, <32> 1,3 dipolar cycloaddition reaction, <33> These <7> - <32> acid-base reaction or the like other than the like.

  In the reaction, the catalyst of the present invention can be used for any reaction method of gas phase reaction or liquid phase reaction. For example, epoxidation reaction of an olefin compound using hydrogen peroxide as an oxidizing agent. In the case of performing the reaction, it is more preferable to perform the reaction in the liquid phase in consideration of the reaction activity. The epoxidation reaction of an olefin compound with hydrogen peroxide can be exemplified below.

  The olefin compound used in the epoxidation reaction may be acyclic or cyclic, and specifically includes ethylene, propylene, 1-butene, 1-hexene, 1-pentene, isoprene, diethylene. Isobutylene, 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 trimers and tetramers, terminal olefins such as 1,3-butadiene, styrene, vinyltoluene, divinylbenzene; 2-butene, 2-octene, 2-methyl-1-hexene, 2,3-dimethyl-2-butene, etc. Intramolecular olefins: cyclopentene, cyclohexene, 1-phenyl-1-cyclohe Rings such as cene, 1-methyl-1-cyclohexene, cycloheptene, cyclooctene, cyclodecene, cyclopentadiene, cyclodecatriene, cyclooctadiene, dicyclopentadiene, methylenecyclopropane, methylenecyclopentane, methylenecyclohexane, vinylcyclohexane, norbornene And olefins. As a kind of olefin compound, 1 type, or 2 or more types can be used.

  The olefin compound used in the epoxidation reaction is also, for example, —CHO, —COOH, —CN, —COOR, —OR (where R represents an alkyl, cycloalkyl, aryl or arylalkyl substituent), an aromatic group. , A functional group such as a halogen group, a nitro group, a sulfonic acid group, a carbonyl group, or a hydroxyl group.

  Practically, the use form of hydrogen peroxide is preferably an aqueous solution of 0.01 to 70% by mass and an alcohol solution, but 100% of hydrogen peroxide can also be used. 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 disubstituted POM compound used is preferably 0.0001 parts by weight or more and preferably 3000 parts by weight or less with respect to 100 parts by weight of the reaction substrate. More preferably, it is 0.01 parts by weight or more and 1500 parts by weight or less. Moreover, when using 2 or more types of said 2 substituted POM compounds as a catalyst, it is preferable to adjust the total weight so that it may become in the said range.

  When the reaction is carried out in the liquid phase, water and / or an organic solvent are used as the solvent to be used, and one or more organic solvents can be used. Examples of the organic solvent used include primary, secondary, and tertiary monohydric alcohols having 1 to 6 carbon atoms such as methanol, ethanol, normal or isopropanol, and tertiary butanol; ethylene glycol, propylene glycol, glycerin, and the like. Polyhydric alcohols; oligomers in which ethylene oxide and propylene oxide are ring-opened such as diethylene glycol and triethylene glycol; ethers such as ethyl ether, isopropyl ether, dioxane and tetrahydrofuran; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and acetyl acetone; Esters such as methyl acetate, ethyl acetate, propyl acetate, butyl acetate and methyl benzoate; carbonates such as ethylene carbonate and propylene carbonate; dimethylformer Nitrogen compounds such as nitromethane, acetonitrile and benzonitrile; phosphorus compounds such as phosphate esters such as triethyl phosphate and diethylhexyl phosphate; halogenated hydrocarbons such as chloroform and dichloromethane; aliphatics such as normal hexane and normal heptane Hydrocarbons; aromatic hydrocarbons such as toluene and xylene; and alicyclic hydrocarbons such as cyclohexane and cyclopentane.

  Among the above solvents, water, alcohols having 1 to 4 carbon atoms, dichloromethane, heptane, acetonitrile, benzonitrile, dimethyl sulfoxide, dimethylformamide, nitromethane, ethyl acetate, butyl acetate, methyl benzoate, ethyl benzoate, dimethyl phthalate It is preferable to use 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 and solvent of the disubstituted POM compound. Among them, at least one of cesium, quaternary alkyl ammonium, and proton is selected as the counter cation. Use at least one solvent selected from nitromethane, ethyl acetate, butyl acetate, methyl benzoate, ethyl benzoate, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate, ethylene carbonate, propylene carbonate More preferred.

  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, Lewis acid and the like, 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, and organic acids such as acetic acid, benzoic acid, formic acid, and trifluoromethanesulfonic acid, and inorganic materials such as zeolites and mixed oxides. Acids are preferred, and 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 preferred. 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 epoxidation 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 is preferably within 150 hours. More preferably, it is 3 minutes or more and within 48 hours. The reaction pressure is not particularly limited but is preferably 20 atm or less. More preferably, it is 10 atm or less, and the reaction can be carried out under reduced pressure.

  The disubstituted POM compound having a tetravalent valence used in the present invention has a maximum of four cations such as protons, alkali metal cations, alkaline earth metal cations, ammonium cations and quaternary alkyl ammonium cations. A di-substituted POM compound that may have one or more protons that cannot be substituted with alkali metal cations or ammonium cations (for example, protons bonded to metal bridging oxygen). Is not included in the number of cations. The non-substitutable proton is, for example, so strong that the heteropolyacid structure cannot be maintained, such as under a basic condition in which the proton is separated, the disubstituted POM compound itself decomposes and the degree of condensation of poly atoms decreases. Refers to the bound proton.

  The four alkyl groups of the quaternary alkylammonium cation may be different from each other or all may be the same, and more preferably all are the same alkyl group. The alkyl group is preferably a straight chain and / or branched alkyl group having 4 to 12 carbon atoms, more preferably a straight chain alkyl group having 4 to 12 carbon atoms, and a straight chain having 4 to 8 carbon atoms. Are more preferable, and tetra-n-butylammonium cation having 4 carbon atoms is most preferable. By combining the disubstituted POM compound anion having the tetravalent valence with an appropriate counter cation, it is possible to construct various micropore structures limited in structure. As a result of providing a unique field having a large surface area due to the presence of the microporous structure, the activity and performance when the disubstituted POM compound is used as a catalyst, a material or the like is dramatically improved. For example, it is possible to appropriately select a solvent and realize a reaction using the disubstituted POM compound as a heterogeneous catalyst, and to exhibit shape selectivity due to a microporous structure.

  The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. “%” Means “mol%” and “TBA” means “tetra-n-butylammonium”.

Reference Example 1 Synthesis Method of K ₈ [β ₂ -SiW ₁₁ O ₃₉ ] · 14H ₂ O Na ₂ SiO ₃ · 9H ₂ O (14 g) was dissolved in ion-exchanged water (100 mL) (solution A). Na ₂ WO ₄ · _{2H 2} O with (181 g) was dissolved in deionized water (300 mL), stirred vigorously added over here 4M aqueous hydrochloric acid (165 mL) 15 sec. After 3 minutes, the previously prepared solution A was added, and the mixture was further stirred for 3 minutes. Then, a 4M aqueous hydrochloric acid solution (80 mL) was added, and the mixture was further stirred for 3 minutes. 7 was set. After 2 minutes, KCl (90 g) was added and stirred gently for 30 minutes. The precipitated solid (K ₈ [β ₂ -SiW ₁₁ O ₃₉ ] · 14H ₂ O was filtered and washed with 2M aqueous potassium chloride solution (100 mL). The yield was improved by about 10% on average as compared with the above literature.

Reference Example 2 Synthesis Method of K ₈ [γ-SiW ₁₀ O ₃₆ ] · 12H ₂ O K ₈ [β ₂ -SiW ₁₁ O ₃₉ ] · 14H ₂ O (30 g) obtained in Reference Example 1 was ion-exchanged. It was made to suspend in water (300 mL) for 1 minute, and the insoluble matter was removed by filtration. Immediately, the pH of the solution was adjusted to 9.1 with 2M aqueous potassium carbonate solution and kept at that value for 16 minutes. To this, KCl (80 g) was added, and the pH of the solution was kept at 9.1 with 2M aqueous potassium carbonate solution for 10 minutes. The precipitated solid was subjected to suction filtration and dried in the air to obtain the target compound K ₈ [γ-SiW ₁₀ O ₃₆ ] · 12H ₂ O (23 g).

(Reference Example 3) K ₈ [γ-GeW ₁₀ O ₃₆ ] · 6H ₂ O Synthesis Method Germanium dioxide (5.4 g) was dissolved in ion-exchanged water (100 mL) (solution A). Na ₂ WO ₄ · 2H ₂ O (182 g) was dissolved in ion-exchanged water (300 mL), and a 4M aqueous hydrochloric acid solution (165 mL) was added thereto over 15 seconds, followed by vigorous stirring. After 3 minutes, the previously prepared solution A was added, and the mixture was further stirred for 3 minutes. Then, a 4M aqueous hydrochloric acid solution (80 mL) was added, and the mixture was further stirred for 3 minutes. 7 was set. After 2 minutes, KCl (90 g) was added and stirred gently for 30 minutes. The precipitated solid was filtered, washed with 2M aqueous potassium chloride (100 mL), and dried for 1 hour. The yield was improved by about 2-3% on average compared to the above literature. The obtained K ₈ [β ₂ -GeW ₁₁ O ₃₉ ] · 14H ₂ O (15 g) was suspended in ion-exchanged water (150 mL) for 1 minute, and insolubles were removed by filtration. Immediately, the pH of the solution was adjusted to 8.8 with 2M aqueous potassium carbonate solution, and kept at that value for 16 minutes. To this, KCl (40 g) was added, and the pH of the solution was kept at 8.8 with 2M aqueous potassium carbonate solution for 10 minutes. The precipitated solid was subjected to suction filtration and dried in the air to obtain the target compound K ₈ [γ-GeW ₁₀ O ₃₆ ] · 6H ₂ O (13 g).

Example 1 (TBA) ₄ [γ-H ₂ SiW ₁₀ O ₃₆ Cu ₂ (μ-1,1-N ₃ ) ₂ ] • Synthesis Method of 9H ₂ O According to the synthesis method of Reference Example 2, K ₈ [γ The synthesis was performed according to the following document, except that -SiW ₁₀ O ₃₆ ] · 12H ₂ O was synthesized.
K. Kamata, S .; Yamaguchi, M .; Kotani, K .; Yamaguchi, N .; Mizuno, “Angevant. Chem. Int. Ed.” (Germany), 2008, 47, p. 2407.
The X-ray crystal structure analysis result of this compound is shown in FIG. From this, it was found that (TBA) ₄ [γ-H ₂ SiW ₁₀ O ₃₆ Cu ₂ (μ-1,1-N ₃ ) ₂ ] has a microporous structure. Moreover, the XRD (powder X-ray diffraction) pattern calculated based on this micropore structure is shown in FIG.

Example 2 Synthesis Method of (TBA) ₄ [γ-H ₂ SiV ₂ W ₁₀ O ₄₀ ] · H ₂ O According to the synthesis method of Reference Example 2, K ₈ [γ-SiW ₁₀ O ₃₆ ] · 12H ₂ O Except for the synthesis, the synthesis was carried out according to the following literature.
Y. Nakagawa, K .; Kamata, M .; Kotani, K .; Yamaguchi, N .; Mizuno, “Angevant. Chem. Int. Ed.” (Germany), 2005, vol. 44, p. 5136. Moreover, the result of the powder X-ray diffraction (XRD) measurement of (TBA) ₄ [γ-H ₂ SiV ₂ W ₁₀ O ₄₀ ] · H ₂ O is as shown in FIG. 2B, and (TBA) ₄ [γ _{-H 2 SiW 10 O 36 Cu 2} (μ-1,1-N 3) 2] · 9H 2 O XRD pattern (calculated) to be consistent with proved. Therefore, (TBA) ₄ [γ-H ₂ SiV ₂ W ₁₀ O ₄₀ ] · H ₂ O is also (TBA) ₄ [γ-H ₂ SiW ₁₀ O ₃₆ Cu ₂ (μ-1,1-N ₃ ) _2. It became clear that it has the same micropore structure as 9H ₂ O.

Example 3 Synthesis Method of (TBA) ₄ [H ₂ GeV ₂ W ₁₀ O ₄₀ ] · 2H ₂ O K ₈ [γ-GeW ₁₀ O ₃₆ ] · 6H ₂ O (15 g) was added to 1M HCl aqueous solution (53 mL). Quickly dissolved. 0.5 M NaVO ₃ aqueous solution (20 mL) was added thereto, and the mixture was stirred at 25 ° C. for 5 minutes. The pH of the solution at this time was 0.4. After removing insolubles, RbCl (7.5 g) was added. The precipitate was collected by suction filtration and washed with cold water (10 mL) (8.3 g). The obtained compound (4.0 g) was dissolved in 250 mL of 0.05 M aqueous hydrochloric acid, tetrabutylammonium bromide (3.8 g) was added, and the mixture was stirred for 30 min. The yellow precipitate was collected by suction filtration, reprecipitated with acetonitrile (50 mL) / water (1 L) solution, recrystallized with acetone (250 mL), filtered and dried under reduced pressure to obtain the target compound. Some (TBA) ₄ [H ₂ GeV ₂ W ₁₀ O ₄₀ ] · 2H ₂ O (2.5 g) was obtained. Moreover, the result of the powder X-ray diffraction (XRD) measurement of (TBA) ₄ [H ₂ GeV ₂ W ₁₀ O ₄₀ ] · 2H ₂ O is as shown in FIG. 2 (c), and (TBA) ₄ [γ-H ₂ SiW ₁₀ O ₃₆ Cu ₂ (μ-1,1-N ₃ ) ₂ ] It was found to be consistent with the XRD pattern (calculated value) of 9H ₂ O. From this, (TBA) ₄ [H ₂ GeV ₂ W ₁₀ O ₄₀ ] · 2H ₂ O is also (TBA) ₄ [γ-H ₂ SiW ₁₀ O ₃₆ Cu ₂ (μ-1,1-N ₃ ) ₂ ]. It became clear that it has the same micropore structure as 9H ₂ O.

Example 4
(TBA) ₄ [γ-H ₂ SiV ₂ W ₁₀ O ₄₀ ] · H ₂ O (5 μmol) was taken in a test tube, and acetonitrile / t-butanol = 1/1 solution (3 mL), 30% hydrogen peroxide. Aqueous solution (0.1 mmol) and 1-octene (0.1 mmol) were added and stirred at 20 ° C. for 24 hours. The analysis was performed by gas chromatography, and the yield of the target epoxy compound was 93% (based on hydrogen peroxide).

(Example 5)
(TBA) ₄ [γ-H ₂ GeV ₂ W ₁₀ O ₄₀ ] · 6H ₂ O (8 μmol) is taken in a test tube, where acetonitrile / t-butanol = 1/1 (3 mL), 30% aqueous hydrogen peroxide solution (0.1 mmol) and 1-octene (0.1 mmol) were added and stirred at 20 ° C. for 250 minutes. The analysis was performed by gas chromatography, and the yield of the target compound, the epoxy compound, was 94% (based on hydrogen peroxide).

(Example 6)
(TBA) ₄ [γ-H ₂ GeV ₂ W ₁₀ O ₄₀ ] · 6H ₂ O (4 μmol) is taken into a test tube, where ethyl acetate / t-butanol = 1/1 (3 mL), 30% hydrogen peroxide An aqueous solution (0.5 mmol) and 1-octene (0.5 mmol) were added, and the mixture was stirred at 32 ° C. for 24 hours. At this time, the catalyst was not dissolved and was uneven. The analysis was performed by gas chromatography, and the yield of the target epoxy compound was 5% (based on hydrogen peroxide).

(Example 7)
Cs ₈ [(SiW ₁₀ O ₃₆ ) ₂ {Hf (H ₂ O)} ₄ O (OH) except that K ₈ [γ-SiW ₁₀ O ₃₆ ] · 12H ₂ O was synthesized according to the synthesis method of Reference Example 2. ₆ ] • 23H ₂ O was synthesized according to the following literature.
Y. Kikukawa, S .; Yamaguchi, K .; Tsuchida, Y. et al. Nakagawa, K .; Uehara, K .; Yamaguchi, N .; Mizuno “Journal of the American Chemical Society (J. Am. Chem. Soc.)” (USA), 2008, vol. 130, p. 5472.
_{Cs 8 [(SiW 10 O 36} ) 2 {Hf (H 2 O)} 4 O (OH) 6] · 23H 2 O (1.3mol%)
Was added to nitromethane (0.8 mL), (+)-citronellal (0.26 mmol) was added thereto, and the mixture was stirred at 75 ° C. for 48 hours. At this time, the catalyst did not dissolve and was uneven. The intramolecular carbonyl-ene reaction proceeded, and isopulegol compound isomers were obtained in a total yield of 86%.

From the above examples, it was found that the following can be said.
As shown in Reference Example 1 and Reference Example 3, in synthesizing [β ₂ -XW ₁₁ O ₃₉ ] ⁸⁻ (X is a kind of element selected from Si or Ge) which is a single deficient POM compound, Si or Ge Yield can be improved by reacting a compound containing one element selected from W and a compound containing W under conditions of pH 6-7, compared with the conventional methods of reacting under conditions of pH = 5-6. Became clear. In addition, as shown in Reference Example 2 and Examples 1 to 3, using the one-deficient POM compound obtained by the present synthesis method, synthesis of a two-deficient POM compound or a two-deficient POM compound It has been found that a disubstituted POM compound can be synthesized by introducing a metal such as Cu or V into the deficient site. Furthermore, (TBA) ₄ [γ-H ₂ SiW ₁₀ O ₃₆ Cu ₂ (μ-1,1-N ₃ ) ₂ ] is newly revealed to have a microporous structure, and (TBA) ₄ [ _{γ-H 2 SiV 2 W 10} O 40] · H 2 O and _{(TBA) 4 [H 2 GeV} 2 W 10 O 40] · 2H 2 O was also found to have the same structure as that of ( Examples 1 to 3). As a result, the POM compound can be used not only as a homogeneous catalyst (Examples 4 to 5) but also as a heterogeneous catalyst (Examples 6 to 7) by selecting an appropriate counter cation (tetrabutylammonium) and a solvent. Was also found to be possible to use.
(Figure 1)

(Figure 2)

Claims (5)

A method for producing a heteropolyoxometalate compound having a disubstituted Keggin structure,
Formula (1) [β ₂ -XW ₁₁ O ₃₉ ] ⁸⁻ (formula obtained by reacting a compound containing one element selected from Si or Ge with a compound containing W under conditions of pH 6-7 In which hetero atom X represents a kind of element selected from Si or Ge, poly atom W represents tungsten, and O represents oxygen. Heteropolyoxometa having a one-deficient Keggin type structure represented by Formula (2) [XW ₁₀ O ₃₆ ] ⁸⁻ obtained using a rate compound as a precursor (wherein, X, which is a heteroatom, represents a kind of element selected from Si or Ge, and is a poly atom) W represents tungsten, and O represents oxygen.) A heteropolyoxometalate compound having a two-deficient Keggin structure represented by: A method for producing a heteropolyoxometalate compound having a disubstituted Keggin structure, wherein at least one element selected from the group is introduced. 2. The disubstituted kegin type compound according to claim 1, wherein the heteropolyoxometalate compound having a two-deficient Keggin structure represented by the formula (2) is a two-deficient structure of X and Si and a γ form. A method for producing a heteropolyoxometalate compound having a structure. The method for producing a heteropolyoxometalate compound having a disubstituted Keggin structure according to claim 1 or 2, wherein the element is Zr, Hf, V, W, Mo, or Cu. A heterogeneous catalyst comprising a heteropolyoxometalate compound having a Keggin structure obtained by the production method according to claim 1. A heteropolymetalate compound having a Keggin structure obtained by the production method according to claim 1, wherein the compound has a heteropolyoxometalate anion having a Keggin structure having a tetravalent valence, and a quaternary. A heteropolyoxometalate compound comprising four cations selected from an alkylammonium cation, an alkali metal cation, an alkaline earth metal cation and / or a proton, and having a structurally limited micropore structure.