JP2012121845A - Method for producing sulfide by deoxygenation of sulfoxide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for deoxygenating a sulfoxide compound under a mild condition, and producing a corresponding sulfide compound with a high yield and selectivity.SOLUTION: The method for producing sulfide is characterized in that sulfoxide is deoxygenated and the corresponding sulfide is obtained in the presence of a surface-immobilized gold catalyst with gold nano-particles fixed on a surface of a carrier and a silane compound. Hydroxyapatite can be suitably used as a carrier. Dimethylphenylsilane, 1,1,3,3-tetramethyldisiloxane etc. can be used as the silane compound.

Description

  The present invention relates to a method for producing a sulfide capable of deoxygenating a sulfoxide under mild conditions to obtain a corresponding sulfide in a high yield. Sulfide is useful as a raw material for fine chemicals such as organic chemicals, pharmaceuticals, and agricultural chemicals.

  Deoxygenation of sulfoxide to sulfide is a very important reaction in the field of organic synthesis and biochemistry. However, the conventional methods have such drawbacks as low catalytic activity, low TON (turnover number) and TOF (TON per unit time), and narrow application range, and are industrially satisfactory methods. It could not be said (Non-Patent Documents 1 to 3).

Dalton Trans., 1727-1733 (2008) Tetrahedron Lett., 48, 9176-9179 (2007) J. Mol. Catal. A., 103, 87-94 (1995)

An object of the present invention is to provide a method capable of producing a corresponding sulfide compound with high yield and selectivity by deoxygenating a sulfoxide compound under mild conditions.
Another object of the present invention is to provide a method capable of industrially efficiently producing a sulfide compound by deoxygenating a sulfoxide compound in the presence of a catalyst.
Still another object of the present invention is to provide a highly versatile production method capable of obtaining a corresponding sulfide compound in a high yield from a wide range of sulfoxide compounds by deoxygenation.

  As a result of intensive studies to achieve the above object, the present inventors desorbed a sulfoxide compound using a silane compound as a reducing agent in the presence of a surface gold immobilization catalyst obtained by immobilizing gold nanoparticles on the surface of a support. It has been found that when oxygen is used, the corresponding sulfide compound can be obtained with a high yield, selectivity and TON (turnover number) under mild conditions.

  That is, the present invention provides a method for producing a sulfide, characterized by desulfurizing a sulfoxide in the presence of a surface gold immobilization catalyst in which gold nanoparticles are immobilized on a support surface and a silane compound to obtain a corresponding sulfide. To do.

  As the carrier, hydroxyapatite is preferable.

  According to the present invention, a corresponding sulfide compound can be produced from a sulfoxide compound with high yield and selectivity. In addition, since a solid catalyst is used, it is easy to handle, and the used catalyst can be easily recovered. Even if it is used in the reaction, the catalytic activity and selectivity are not lowered, so that it can be used repeatedly. Moreover, since the TON (turnover number) of the catalyst is remarkably large, the sulfide compound can be produced inexpensively and industrially efficiently. In addition, the production method of the present invention has wide substrate adaptability, can be applied to various sulfide compounds, and is excellent in versatility.

[Surface gold immobilization catalyst]
The surface gold-immobilized catalyst used in the present invention is obtained by immobilizing gold nanoparticles on the surface of a carrier. The carrier is not particularly limited, and for example, hydroxyapatite (HAP), titania (TiO ₂ ), alumina (Al ₂ O ₃ ), magnesia (MgO), silica (SiO ₂ ), ceria (CeO ₂ ), activated carbon. (C) etc. can be mentioned. In the present invention, among them, hydroxyapatite (HAP), titania (TiO ₂ ), alumina (Al ₂ O ₃ ) and the like are preferable as the carrier, and in particular, the target compound can be obtained with extremely high yield and selectivity. Hydroxyapatite (HAP) is preferable. Therefore, the surface gold-immobilized catalyst in the present invention is preferably a hydroxyapatite-immobilized gold nanoparticle catalyst (hereinafter sometimes referred to as “AuHAP”) in which gold nanoparticles are immobilized on the hydroxyapatite surface.

The hydroxyapatite is, for example, the following formula (1)
Ca _10-Z (HPO ₄ ) _Z (PO ₄ ) _6-Z (OH) _2-Z · nH ₂ O (1)
(Wherein, Z is a number satisfying 0 ≦ Z ≦ 1, n is a number from 0 to 2.5)
It is a compound represented by these.

  Hydroxyapatite can be prepared, for example, by a wet synthesis method. Specifically, in the wet synthesis method, a calcium solution and a phosphoric acid solution are successively dropped over a long period of time into a buffer solution in which the pH is maintained at a predetermined value of 7.4 or more at a molar concentration ratio of 10: 6. Thus, hydroxyapatite is precipitated in the buffer solution, and the precipitated hydroxyapatite is collected.

  Examples of hydroxyapatite that can be suitably used in the present invention include, for example, trade name “tricalcium phosphate” manufactured by Wako Pure Chemical Industries, Ltd.

The method for immobilizing the gold nanoparticles on the surface of the carrier is not particularly limited. For example, a gold compound such as gold chloride (AuCl ₃ ) or chloroauric acid (HAuCl ₄ ) and a carrier such as hydroxyapatite And the like. After the gold ions are immobilized on the surface of a carrier such as hydroxyapatite by mixing in a solvent, the gold ions are reduced by an appropriate method.

  The solvent only needs to dissolve the gold compound to be used, and examples thereof include water, acetone, and alcohols. The concentration of the gold compound in the solution for fixing the gold nanoparticles is not particularly limited, and can be appropriately selected from a range of 0.1 to 100 mM, for example. Although the temperature at the time of stirring can be selected from the range of 20-80 degreeC, for example, it is normally performed at room temperature (25 degreeC). Although stirring time changes also with the temperature at the time of stirring, when stirring at 25 degreeC, for example, it is about 6 to 24 hours, Preferably, it is about 8 to 12 hours. After completion of the stirring, it may be washed with water or an organic solvent as necessary, and dried by vacuum drying or the like.

Examples of the reducing agent used for the reduction include borohydride complex compounds such as sodium borohydride (NaBH ₄ ), lithium borohydride (LiBH ₄ ), potassium borohydride (KBH ₄ ), hydrazine, hydrogen (H ₂ ), silane compounds such as dimethylphenylsilane, hydroxy compounds and the like. Examples of the hydroxy compound include alcohol compounds such as a primary alcohol and a secondary alcohol. The hydroxy compound may have a plurality of hydroxyl groups, and may be any of monohydric alcohol, dihydric alcohol, polyhydric alcohol and the like.

Examples of the reducing agent used for immobilizing gold nanoparticles on the surface of a carrier such as hydroxyapatite in the present invention include sodium borohydride (NaBH ₄ ), lithium borohydride (LiBH ₄ ), and hydrogen. preferably borohydride complex compounds such as potassium borohydride (KBH _4), in particular, potassium borohydride (KBH ₄₎ is preferable. The surface gold-immobilized catalyst obtained by reduction with potassium borohydride (KBH ₄ ) tends to have a smaller average particle size of the immobilized metal particles, thereby increasing the specific surface area. The catalytic activity can be remarkably improved.

  The gold nanoparticle content in the surface gold-immobilized catalyst is, for example, 0.01 to 3 mmol, preferably 0.02 to 0.5 mmol, particularly preferably 0.03 to 0, per 1 g of a carrier such as hydroxyapatite. .1 mmol. When the gold nanoparticle content in the surface gold-immobilized catalyst exceeds the above range, the catalytic action tends to decrease.

[Silane compound]
In the present invention, the silane compound used as the reducing agent is not particularly limited as long as it is a silane compound having at least one Si-H bond in the molecule. For example, an aromatic silane compound, an aliphatic silane Examples thereof include compounds and polysiloxanes.

  Examples of the aromatic silane compound include dimethylphenylsilane, dimethyl-p-chlorophenylsilane, dimethyl-p-methoxyphenylsilane, methyldiphenylsilane, diethylphenylsilane, ethyldiphenylsilane, diphenylsilane, 1,4-bis ( And dimethylsilyl) benzene.

  Examples of the aliphatic silane compound include t-butyldimethylsilane, tri (n-butyl) silane, tri (isopropyl) silane, triethylsilane, dimethyloctadecanoylsilane, and the like.

  Examples of the polysiloxane include 1,1,3,3, -tetramethyldisiloxane, 1,1,3,3-tetraethyldisiloxane, 1,1,3,3-tetraphenyldisiloxane, hexamethyl And polyalkyl and / or aryl hydrosiloxanes such as trisiloxane, octamethyltetrasiloxane, decamethylpentasiloxane, etc. (polymethylhydrosiloxane, polyethylhydrosiloxane, polyphenylhydrosiloxane, polymethylphenylhydrosiloxane, etc.).

（式中、Ｒ¹、Ｒ²は、同一又は異なって、置換基を有していてもよい炭化水素基、又は置換基を有していてもよく且つ複素環を構成する炭素原子が式中に示される硫黄原子に結合している複素環式基を示す。Ｒ¹、Ｒ²は互いに結合して、式中に示される硫黄原子とともに環を形成していてもよい）
で表される化合物が挙げられる。 [Sulphoxide]
In the production method of the present invention, as the sulfoxide used as a substrate (raw material component), for example,

(In the formula, R ¹ and R ² are the same or different, and a hydrocarbon group which may have a substituent, or a carbon atom which may have a substituent and constitutes a heterocyclic ring is And R ¹ and R ² may be bonded to each other to form a ring together with the sulfur atom shown in the formula)
The compound represented by these is mentioned.

Examples of the hydrocarbon group in R ¹ and R ² include an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group in which two or more of these groups are bonded.

  Examples of the aliphatic hydrocarbon group include 1 to 20 carbon atoms (preferably 1 to 1) such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, t-butyl, pentyl, hexyl, decyl, and dodecyl groups. An alkyl group of about 10); an alkenyl group of about 2 to 20 carbon atoms (preferably 2 to 10) such as vinyl, allyl and 1-butenyl groups; and 2 to 20 carbon atoms such as ethynyl and propynyl groups (preferably 2 to 2). 10) about an alkynyl group.

Examples of the alicyclic hydrocarbon group include a cycloalkyl group having about 3 to 20 members (preferably 3 to 15 members, more preferably 5 to 8 members) such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cyclooctyl groups. A cycloalkenyl group of about 3 to 20 members (preferably 3 to 15 members, more preferably 5 to 8 members) such as cyclopentenyl and cyclohexenyl groups; a perhydronaphthalen-1-yl group, norbornyl, adamantyl, tetracyclo; [4.4.0.1 ^2,5 . 1 ^7,10 ] bridged cyclic hydrocarbon groups such as dodecan-3-yl groups.

  Examples of the aromatic hydrocarbon group include aromatic hydrocarbon groups having about 6 to 14 (preferably 6 to 10) carbon atoms such as phenyl and naphthyl groups.

Examples of the hydrocarbon group in which the aliphatic hydrocarbon group and the alicyclic hydrocarbon group are bonded include cycloalkyl-alkyl groups such as cyclopentylmethyl, cyclohexylmethyl, and 2-cyclohexylethyl groups (for example, C _3-12 cyclohexane). Alkyl-C _1-4 alkyl group and the like).

The hydrocarbon group in which an aliphatic hydrocarbon group and an aromatic hydrocarbon group are bonded includes an aralkyl group (for example, a C _7-18 aralkyl group) and an alkyl-substituted aryl group (for example, about 1 to 4 C _{1 -4} alkyl group-substituted phenyl group or naphthyl group), aryl-substituted C _2-10 alkenyl group (for example, 2-phenylvinyl group) and the like.

  The hydrocarbon group may have various substituents such as halogen atoms, oxo groups, hydroxyl groups, substituted oxy groups (eg, alkoxy groups, aryloxy groups, aralkyloxy groups, acyloxy groups, etc.), carboxyl groups, substituted Oxycarbonyl group (alkoxycarbonyl group, aryloxycarbonyl group, aralkyloxycarbonyl group, etc.), cyano group, nitro group, acyl group, substituted or unsubstituted amino group (hydrocarbon group substituted amino group, acyl group substituted amino group, none A substituted amino group, etc.), a sulfo group, a heterocyclic group and the like. The hydroxyl group and carboxyl group may be protected with a protective group commonly used in the field of organic synthesis. In addition, an aromatic or non-aromatic heterocycle may be condensed with the ring of the alicyclic hydrocarbon group or aromatic hydrocarbon group.

The heterocyclic ring constituting the heterocyclic group in R ¹ and R ² includes an aromatic heterocyclic ring and a non-aromatic heterocyclic ring. Examples of such a heterocyclic ring include a heterocyclic ring containing an oxygen atom as a hetero atom (for example, 5-membered ring such as furan, tetrahydrofuran, oxazole, isoxazole, and γ-butyrolactone ring, 4-oxo-4H-pyran, tetrahydro 6-membered ring such as pyran, morpholine ring, condensed ring such as benzofuran, isobenzofuran, 4-oxo-4H-chromene, chroman, isochroman ring, 3-oxatricyclo [4.3.1.1 ^4,8 ] undecane 2-one ring, a bridged ring such as 3-oxatricyclo [4.2.1.0 ^4,8 ] nonan-2-one ring), a heterocycle containing a sulfur atom as a hetero atom (for example, thiophene, 5-membered ring such as thiazole, isothiazole, thiadiazole ring, 6-membered ring such as 4-oxo-4H-thiopyran ring, benzothiophene ring Any condensed ring), heterocycles containing nitrogen atoms as heteroatoms (eg, 5-membered rings such as pyrrole, pyrrolidine, pyrazole, imidazole, and triazole rings, 6-membered rings such as pyridine, pyridazine, pyrimidine, pyrazine, piperidine, and piperazine rings) Ring, indole, indoline, quinoline, acridine, naphthyridine, quinazoline, a condensed ring such as a purine ring, etc.). In addition to the substituents that the hydrocarbon group may have, the heterocyclic group includes an alkyl group (eg, a C _1-4 alkyl group such as a methyl or ethyl group), a cycloalkyl group, an aryl group It may have a substituent such as (for example, phenyl, naphthyl group).

R ¹ and R ² may be bonded to each other to form a ring together with the sulfur atom shown in the formula. Examples of such a ring include 3- to 15-membered (particularly 5 to 8-membered) sulfur-containing non-aromatic heterocycles such as thiirane ring, thietane ring, thiolane ring, thiane ring, thiepan ring, and thiocan ring.

  In the present invention, representative examples of the sulfoxide used as a substrate include, for example, dimethyl sulfoxide, ethyl methyl sulfoxide, methyl propyl sulfoxide, dipropyl sulfoxide, dibutyl sulfoxide, diphenyl sulfoxide, methyl phenyl sulfoxide, ethyl phenyl sulfoxide, phenyl vinyl sulfoxide. , Dibenzyl sulfoxide, methoxycarbonylmethyl-phenyl-sulfoxide, cyanomethyl-phenyl-sulfoxide, (2-propynyl) -phenyl-sulfoxide, (4-acetylphenyl) -methyl-sulfoxide, and the like.

（式中、Ｒ¹、Ｒ²は前記に同じ）
で表される対応するスルフィドが得られる。 [Production of sulfide]
In the present invention, sulfoxide is deoxygenated in the presence of a surface gold immobilization catalyst in which gold nanoparticles are immobilized on the support surface and a silane compound, to produce a corresponding sulfide. When the compound represented by the formula (2) is used as the sulfoxide, the following formula (3)

(Wherein R ¹ and R ² are the same as above)
The corresponding sulfide represented by

  The amount of the surface gold immobilization catalyst used is, for example, about 0.0001 to 50 mol%, particularly about 0.01 to 20 mol% as gold (Au) with respect to the sulfoxide as a substrate, About 0.1-5 mol% is preferable.

  The amount of the silane compound is, for example, 0.8 to 50 mol, preferably 0.9 to 20 mol, and more preferably 1 to 10 mol with respect to 1 mol of sulfoxide as a substrate. If the amount of the silane compound used is too small, the yield of the target compound tends to decrease. Conversely, if the amount of the silane compound used is too large, it is economically disadvantageous.

  The above reaction is preferably carried out in a liquid phase. Examples of the solvent used include fluorine solvents such as trifluorotoluene, fluorobenzene, and fluorohexane; aromatic hydrocarbons (for example, benzene, toluene, xylene, chlorobenzene). , Nitrobenzene, etc.) and aliphatic hydrocarbons (eg, pentane, hexane, heptane, octane, cyclohexane, methylcyclohexane, etc.); 1,2-dioxane, 1,3-dioxane, 1,4-dioxane, tetrahydrofuran And ethers such as tetrahydropyran, diethyl ether and dimethyl ether; esters such as ethyl acetate, propyl acetate and butyl acetate; and mixtures thereof. Of these, hydrocarbons are preferable as the solvent, and aromatic hydrocarbons such as toluene are particularly preferable. Moreover, as a usage-amount of a solvent, it is preferable to use in the range from which the density | concentration of a substrate will be about 2 to 10 weight%, for example.

  The above reaction can be carried out by a conventional method such as batch, semi-batch or continuous.

  According to the production method of the present invention, the reaction can proceed smoothly even under mild conditions. The reaction temperature can be appropriately adjusted according to the type of substrate, the type of target product, and the like, and is, for example, -20 to 200 ° C, preferably about 0 to 150 ° C, particularly preferably about 0 to 100 ° C. It is. The reaction time can be appropriately adjusted according to the reaction temperature and the like, and is, for example, about 5 minutes to 120 hours, preferably about 10 minutes to 90 hours.

  After completion of the reaction, the reaction product can be separated and purified by separation means such as filtration, concentration, distillation, extraction, crystallization, recrystallization, column chromatography, etc., or a separation means combining these.

  According to the production method of the present invention, the deoxygenation reaction of sulfoxide can be carried out under mild conditions. Further, since the surface gold-immobilized catalyst exhibits a high TON (turnover number), the corresponding sulfide can be produced efficiently with a small amount of catalyst. Further, not only the activity but also the reaction selectivity is high, and it can be applied to a wide range of sulfoxides.

  In addition, since the surface gold-immobilized catalyst used in the reaction is supported on a carrier, the supported gold nanoparticles are not easily eluted into the reaction solution and are not easily deteriorated. The surface gold-immobilized catalyst can be easily recovered from the reaction solution by physical separation techniques such as filtration and centrifugation. The recovered surface gold-immobilized catalyst can be reused as it is or after washing and drying. The washing treatment can be performed by a method of washing several times (for example, 2 to 3 times) with an appropriate solvent (for example, an organic solvent such as water or toluene).

  The recovered surface gold-immobilized catalyst exhibits almost the same catalytic ability as an unused surface gold-immobilized catalyst. Thus, according to the present invention, the surface gold-immobilized catalyst that occupies a large proportion of the manufacturing cost can be recovered and repeatedly used, so that the manufacturing cost can be significantly reduced.

  EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited by these Examples.

Production Example 1
In a 50 mL eggplant-shaped flask, 0.1 mmol of chloroauric acid (HAuCl ₄ ) and 50 mL of ion exchange water are added, and 1.0 g of hydroxyapatite (HAP; tricalcium phosphate, manufactured by Wako Pure Chemical Industries, Ltd.) is added to the solution. After adding and stirring at room temperature for 2 minutes, ammonia (5 mmol) was added and further stirred for 12 hours. Thereafter, the mixture was filtered with suction, washed with deionized water (1 L), and vacuum-dried to obtain Au (III) HAP (Au: trivalent) (Au: 0.083 mmol / g).
In a 50 mL eggplant-shaped flask, water (50 mL) was added and dissolved in KBH ₄ (0.9 mmol), and 0.9 g of the obtained Au (III) HAP was added thereto, followed by stirring at room temperature for 1 hour in an argon atmosphere. did.
After stirring, it is filtered by suction, washed with 1 L of deionized water, and vacuum-dried for 24 hours to obtain AuHAP (Au: 0 valent) as a reddish purple powder (Amount of Au supported on 1 g of carrier: 0.083 mmol / g) It was. The average particle size of the obtained powder was 3.0 nm (standard deviation σ = 0.9 nm).

Production Example 2
A catalyst (Au / Al ₂ O ₃ ) having gold nanoparticles immobilized on the alumina surface was obtained in the same manner as in Production Example 1 except that alumina (Al ₂ O ₃ ) was used instead of hydroxyapatite.

Production Example 3
A catalyst (Au / TiO ₂ ) having gold nanoparticles immobilized on the titania surface was obtained in the same manner as in Production Example 1 except that titania (TiO ₂ ) was used instead of hydroxyapatite.

Production Example 4
A catalyst (Au / MgO) having gold nanoparticles immobilized on the surface of magnesia was obtained in the same manner as in Production Example 1 except that magnesia (MgO) was used instead of hydroxyapatite.

Production Example 5
A catalyst (Au / SiO ₂ ) having gold nanoparticles immobilized on the silica surface was obtained in the same manner as in Production Example 1 except that silica (SiO ₂ ) was used instead of hydroxyapatite.

Example 1
In a pressure-resistant reaction tube made of glass, 0.10 g of AuHAP obtained in Production Example 1 (Au: 0.0083 mmol; 1.6 mol% with respect to diphenyl sulfoxide), 3 mL of 1,4-dioxane, 0.5 mmol of diphenyl sulfoxide, dimethyl 1 mmol of phenylsilane was added, and the mixture was stirred at 30 ° C. for 1 hour under an argon atmosphere (1 atm (= 0.10 MPa)) to obtain diphenyl sulfide (yield 99% or more, selectivity 99% or more). The yield and selectivity were determined by liquid chromatography (internal standard method).

Example 2
Instead of AuHAP obtained in Production Example 1, after completion of the reaction of Example 1, the reaction solution was filtered to separate the catalyst, washed with 10 mL of 1,4-dioxane three times, and then at room temperature (25 ° C.). Diphenyl sulfide was obtained in the same manner as in Example 1 except that AuHAP obtained by drying under reduced pressure was used (yield 99% or more, selectivity 99% or more).

Example 3
Instead of AuHAP obtained in Production Example 1, after completion of the reaction of Example 2, the reaction solution was filtered to separate the catalyst, washed with 10 mL of 1,4-dioxane three times, and then at room temperature (25 ° C.). Diphenyl sulfide was obtained in the same manner as in Example 1 except that AuHAP obtained by drying under reduced pressure was used (yield 99%, selectivity 99% or more).

Example 4
To a glass pressure-resistant reaction tube, 0.01 g of AuHAP obtained in Production Example 1 (Au: 0.8 μmol), 20 mL of 1,4-dioxane, 10 mmol of diphenyl sulfoxide, and 20 mmol of dimethylphenylsilane were added, and an argon atmosphere (1 atm ( = 0.10 MPa)), and stirring at 130 ° C. for 48 hours gave diphenyl sulfide (yield 94%, selectivity 99% or more). Yield and selectivity were determined by liquid chromatography (internal standard method). The isolated yield was 93%. TON and TOF were 10000 and 200 hr ⁻¹ , respectively. These values are three orders of magnitude higher than conventional catalysts.

Examples 5-12
The corresponding sulfide was obtained in the same manner as in Example 1 except that the substrate (sulfoxide) was changed to the substrate shown in Table 1 below. In Examples 9 and 11, the reaction temperature was 60 ° C. The results of Examples 1-12 are shown in Table 1. In the table, the number in parentheses in the yield column is the isolated yield.

Example 13
Diphenyl sulfide was obtained in the same manner as in Example 1 except that 0.25 mmol of diphenyl sulfoxide as a substrate was used and 0.5 mL of polymethylhydrosiloxane (PMHS) was used instead of dimethylphenylsilane. %, Selectivity 99% or more).

Example 14
Diphenyl sulfide was obtained in the same manner as in Example 1 except that 1 mmol of methyldiphenylsilane was used instead of dimethylphenylsilane (yield 52%, selectivity 99% or more).

Example 15
Diphenyl sulfide was obtained in the same manner as in Example 1 except that 3 mL of tetrahydrofuran was used instead of 1,4-dioxane (yield 98%, selectivity 99% or more).

Example 16
Diphenyl sulfide was obtained in the same manner as in Example 1 except that 3 mL of toluene was used instead of 1,4-dioxane (yield 94%, selectivity 99% or more).

Example 17
Diphenyl sulfide was obtained in the same manner as in Example 1 except that 3 mL of ethyl acetate was used instead of 1,4-dioxane (yield 89%, selectivity 99% or more).

Example 18
Except for using Au / Al ₂ O ₃ obtained in Production Example 2 instead of AuHAP obtained in Production Example 1 (Au: 1.6 mol% with respect to diphenyl sulfoxide), the same as in Example 1, Diphenyl sulfide was obtained (yield 94%, selectivity 99% or more).

Example 19
In the same manner as in Example 1 except that Au / TiO ₂ (Au: 1.6 mol% with respect to diphenyl sulfoxide) obtained in Production Example 3 was used instead of AuHAP obtained in Production Example 1, diphenyl sulfide was used. (Yield 89%, selectivity 99% or more).

Example 20
Diphenyl sulfide was prepared in the same manner as in Example 1 except that Au / MgO obtained in Production Example 4 (Au: 1.6 mol% with respect to diphenyl sulfoxide) was used instead of AuHAP obtained in Production Example 1. Obtained (yield 76%, selectivity 99% or more).

Example 21
In the same manner as in Example 1, except that Au / SiO ₂ (Au: 1.6 mol% with respect to diphenyl sulfoxide) obtained in Production Example 5 was used instead of AuHAP obtained in Production Example 1, diphenyl sulfide was used. (Yield 64%, selectivity 99% or more).

Comparative Example 1
Diphenyl sulfide was not obtained when the same operation as in Example 1 was performed except that hydroxyapatite (HAP) was used instead of AuHAP obtained in Production Example 1.

Comparative Example 2
Diphenyl sulfide was not obtained when the same operation as in Example 1 was performed except that the catalyst was not used.

Claims (2)

  A method for producing a sulfide, comprising desulfurizing a sulfoxide in the presence of a surface gold immobilization catalyst having gold nanoparticles immobilized on a carrier surface and a silane compound to obtain a corresponding sulfide.   The sulfide production method according to claim 1, wherein hydroxyapatite is used as a carrier.