JP2016131949A - Organic synthetic method using alloyed elements in oxidized membrane of active metal as disproportionation catalyst - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an alloy-containing complex by a very simple production method, the complex containing a little amount of transition metal elements and being able to be produced economically, being stable, and having high catalyst reaction activity, and also to provide a catalyst for cross-coupling reaction containing the alloy-containing complex, and a cross-coupling reaction using the catalyst for cross-coupling reaction without performing a reduction treatment with a hydrogen gas and the like.SOLUTION: The present invention relates to a complex comprising: an alloy comprising a metal active towards oxygen and a transition metal having catalytic activity at the center of the complex; an oxidized membrane formed of the metal active towards oxygen around the alloy; and a zero (0)-valent metal atom of the transition metal having catalytic activity in the oxidized membrane. The present invention further relates to a production method of the complex, a catalyst for a cross-coupling reaction containing the complex, and a cross-coupling reaction using the catalyst for cross-coupling reaction.SELECTED DRAWING: None

Description

  The present invention relates to a functional metal material, particularly a novel alloy-containing composite, and a method for producing the same, and a method for using the same in organic synthesis as a heterogeneous catalyst.

  In recent years, alloys as functional metal materials have attracted attention. For example, alloys as functional metal materials can be used for heterogeneous catalysts for organic synthesis, photocatalysts, gas storage, gas separation, gas sensor devices, magnetic heads, shape memory alloys, electrodes, hydrogen storage alloys, etc. Is known. In particular, as a catalyst for organic synthesis, a homogeneous catalyst that is soluble in a solvent in a reaction system and a heterogeneous catalyst that is insoluble are known. Here, the heterogeneous catalyst is a catalyst in which a transition metal exhibiting catalytic activity is physically adsorbed and supported on a porous inorganic oxide (eg, zeolite). Although the homogeneous catalyst has an advantage of high reaction selectivity, it is problematic to mix it in the organically synthesized product. Such a heterogeneous catalyst, unlike a homogeneous catalyst, has the disadvantage of low reaction selectivity, but on the other hand, it is easy to separate from the reaction system, and the catalyst composition hardly changes structurally. As such, it has the advantage of high stability.

  A conventional heterogeneous catalyst using an alloy has a drawback that the reaction proceeds starting from defects on the surface of the alloy, and it is difficult to control the selectivity of the reaction. Moreover, when there is much content of the transition metal in an alloy, a transition metal itself will aggregate by forming a large amount of transition metals at the time of the manufacture, and a cluster will be formed. In the case of such a cluster structure, there are edge atoms, terrace atoms, and corner atoms depending on the coordination position of the atoms, and the reactivity is different for each position, so that the selectivity is similarly reduced ( Non-Patent Documents 1 and 2).

  In addition, as a conventional method for producing an alloy catalyst, a salt containing a transition metal is generally carried on a carrier such as a porous inorganic oxide (for example, zeolite) to produce an alloy. A device for firmly holding the transition metal on the carrier has been devised (Patent Document 1). Moreover, a complicated process is required for the carrying. Furthermore, in recent studies, attempts have been made to increase the surface area by nano-catalyzing catalyst molecules in order to increase the reaction point of the catalyst (Non-patent Documents 3 and 4). However, since a bulk alloy itself has a hard property, it is difficult to make a fine particle.

  Furthermore, a recent method for producing an alloy catalyst is a process in which a solid solution composed of two or more kinds of transition metal elements is formed and added to a support to uniformly disperse an element exhibiting catalytic activity in the alloy. It has been. However, such a process goes through complicated reaction steps, and when the catalyst itself is exposed to the atmosphere, it is quickly deactivated and must be reduced in a hydrogen atmosphere (Non-Patent Document 5). There was a problem of requiring treatment (heat treatment at 100-500 ° C.) (Patent Document 2). Therefore, development of an alloy heterogeneous catalyst with a simple alloy manufacturing process, low transition metal atom content, low cost manufacturing, high catalytic activity, and high reaction activity. Is desired.

JP 2008-012419 A JP-A-10-137487

Shigeru Inui, Masaru Ichikawa, Introduction to Homogeneous and Heterogeneous Catalysts-Future Catalyst Chemistry-, Maruzen Co., Ltd. Yoshio Ono, Hideshi Hattori; Solid Base Catalysis, Springer Science & Business Media (2012) 84. Tuan T. Dang, Yinghuai Zhu, Joyce SY Ngiam, Subhash C. Ghosh, Anqi Chen, and Abdul M. Seayad; Palladium Nanoparticles Supported on ZIF-8 As an Efficient Heterogeneous Catalyst for Aminocarbonylation, ACS Catalysis 3 (2013) 1406-1410 . Megumi Hyotanishi, Yuto Isomura, Hiroko Yamamoto, Hideya Kawasakia, Yasushi Obora; Surfactant-free synthesis of palladium nanoclusters for their use in catalytic cross-coupling reactions, Chemical Communications, 47 (2011) 5750-5752. B. C. Gates; Supported Metal Clusters: Synthesis, Structure, and Catalysis, Chemical Reviews (1995) 511-522.

  It is an object of the present invention to obtain an alloy-containing composite that has a low content of transition metal atoms and can be manufactured at low cost, is stable, and has a high catalytic activity and selectivity by an extremely simple manufacturing method. And Another object of the present invention is to provide a cross-coupling reaction catalyst containing the alloy-containing composite and a cross-coupling reaction using the cross-coupling reaction catalyst without reduction treatment of hydrogen gas or the like.

  Therefore, in order to achieve the above-mentioned object, the present inventors dissolved a transition metal element having catalytic activity in an atmosphere of an inert metal element and an inert gas with respect to oxygen, alloyed it, and then dissolved the dissolved alloy. By forming an oxide film derived from a metal active to oxygen by oxidizing the metal, a transition metal element having catalytic activity is uniformly dispersed in the oxide film, and has self-repairing properties. It has been found that an alloy-containing composite that is stable and can be easily changed in shape can be obtained. The present inventors also found that the heterogeneous catalyst containing the obtained alloy-containing composite is excellent as a catalyst for cross-coupling reaction. That is, the present invention is as follows.

Item [1] An alloy composed of a metal active to oxygen and a transition metal having catalytic activity at the center of the composite,
Around the alloy, an oxide film formed from the oxygen-active metal, and a zero (0) valent metal atom of the transition metal having the catalytic activity in the oxide film,
A complex comprising
Item [2] The composite according to Item [1], wherein the metal active with respect to oxygen is at least one transition metal selected from the group consisting of Group 4A to 6A, 3B and 4B transition metals.
Item [3] The metal active against oxygen is titanium (Ti), zirconium (Zr), hafnium (Hf), chromium (Cr), vanadium (V), niobium (Nb), tantalum (Ta), aluminum The composite according to any one of Items [1] and [2], which is at least one transition metal selected from the group consisting of (Al) and silicon (Si).
Item [4] In any one of Items [1] to [3], the transition metal having catalytic activity is at least one transition metal selected from the group consisting of Group 7 to Group 11 transition metals. The complex described.
Item [5] The oxygen active metal is titanium (Ti), and the catalytic transition metal is palladium (Pd), platinum (Pt), rhodium (Rh) or rhenium (Re). The complex according to any one of Items [1] to [4].
Item [6] The item [1] to [5], wherein the transition metal having catalytic activity is contained in the alloy in a ratio of about 0.01 to about 15 mol% with respect to the metal active with respect to oxygen. The complex according to any one of the above.
Item [7] The composite according to any one of Items [1] to [6], wherein the oxide film has a thickness of about 5 nm or more.
Item [8] The complex according to any one of Items [1] to [7], which has self-healing properties.

Item [9] A transition metal element having catalytic activity is blended at a ratio of about 0.01 to about 15 mol% with respect to a metal element active against oxygen, and the mixture is melted to produce an alloy; and,
An oxide film is formed by oxidizing the manufactured alloy to obtain a composite.
The manufacturing method of the composite_body | complex of any one of claim | item [1] thru | or [8] including this.

Item [10] A catalyst for cross-coupling reaction, comprising the composite according to any one of items [1] to [8].
Item [11] A cross-coupling reaction using the complex according to any one of Items [1] to [8] as a catalyst.
Term [12] Formula: AX
(Where
A is an unsubstituted or substituted aryl group; and
X is a halogen, a mesylate group, a tosylate group, or a triflate group)
A compound represented by
Formula: BY
(Where
B is an unsubstituted or substituted aryl group;
Y is B (OR ¹ ) ₂ and R ¹ is hydrogen)
By reacting with a compound represented by
Formula: AB
(In the formula, A and B are as described above.)
A cross-coupling reaction according to item [11], comprising obtaining a product represented by the formula:
Item [13] The cross-coupling reaction according to any one of Items [11] and [12], which does not require a hydrogen reduction treatment of the catalyst.
Item [14] Use of the composite according to any one of Items [1] to [8] as a gas storage, gas separation, gas sensor device, or heterogeneous catalyst.

  The present invention is an excellent alloy-containing composite that can be produced inexpensively with a low content of transition metal atoms, has self-healing properties, and has high catalytic activity and selectivity by an extremely simple production method. You can get a body. Moreover, the obtained alloy-containing composite exhibits excellent activity as a catalyst for cross-coupling reaction.

It is drawing which shows the schematic diagram of the structure of the alloy containing composite_body | complex of this invention. The X-ray diffraction profile of an alloy comprising complexes of the present invention _{(Ti 0.99 Pd 0.01)} is a drawing showing. It is drawing which shows the X-ray photoelectron spectroscopy analysis result of the alloy containing composite_body | complex of this invention whose transition metal is palladium. The valence state (change of chemical shift) of palladium accompanying alloying with titanium from the surface of the composite is shown. It is drawing which shows the X-ray photoelectron spectroscopy analysis result of the alloy containing composite_body | complex of this invention whose transition metal is palladium. The valence state (change in peak intensity) of palladium accompanying sputtering from the surface of the composite is shown. It is drawing which shows the X-ray photoelectron spectroscopy analysis result of the alloy containing composite_body | complex of this invention whose transition metal is platinum. The valence state (change of chemical shift) of platinum accompanying sputtering from the surface of the composite is shown. It is drawing which shows the reaction with respect to the hydrogen molecule of the alloy containing composite_body | complex of this invention.

The present invention is described in further detail below.
(Definition)
The definitions of terms used in the present specification and claims are shown below. Unless otherwise indicated, the first definition given for a group or term herein applies to the group or term herein individually or as part of another group.

(Manufacture of complex)
The term “composite” means an alloy composed of a metal active to oxygen and a transition metal having catalytic activity, an oxide film formed from the metal active to oxygen, and a transition metal having the catalytic activity The structure containing a zero (0) valent metal atom. The structure of the composite is formed of an alloy composed of a metal active against oxygen and a transition metal having catalytic activity at the center of the composite; formed from a metal active against oxygen around the alloy. An oxide film; and the oxide film contains a zero (0) -valent metal atom of the transition metal having catalytic activity (see FIG. 1). Here, the zero (0) valent metal atoms of the transition metal having catalytic activity are not present in physical adsorption, but are present uniformly in the oxide film in a mixed manner. Further, the zero (0) valent transition metal atom is present in the oxide film, and thus has the advantage of not being poisoned.

  The term “oxygen-active metal” means a metal that reacts with oxygen to oxidize to form an oxide. For example, at least one metal selected from the group consisting of Group 4A to 6A, 3B, and 4B metal can be used. Specific examples include titanium (Ti), zirconium (Zr), hafnium (Hf), chromium (Cr), vanadium (V), niobium (Nb), tantalum (Ta), aluminum (Al), and silicon (Si). At least one metal selected from the group consisting of, but not limited to. Here, the oxygen donor may be either an oxygen donor reagent (for example, hydrogen peroxide or nitric acid) or oxygen molecules in the air.

  The term “transition metal having catalytic activity” means a transition metal having catalytic activity in an organic synthesis reaction. As the organic synthesis reaction, for example, a coupling reaction, typically a cross-coupling reaction is intended. Examples include, but are not limited to, at least one transition metal selected from the group consisting of Group 7 to Group 11 transition metals. Specific examples include Group 7 transition metals (eg, manganese (Mn), rhenium (Re), Group 8 transition metals (eg, iron (Fe), ruthenium (Ru), osmium (Os)), Group 9 Transition metals (eg, cobalt (Co), rhodium (Rh), iridium (Ir)), Group 10 transition metals (eg, nickel (Ni), palladium (Pd), platinum (Pt)), and Group 11 transitions This means at least one transition metal selected from the group consisting of metals (for example, copper (Cu), silver (Ag), gold (Au)), and typically includes Group 10 transition metals such as platinum. Palladium is preferred.

  The term “alloy” means an alloy composed of a metal active to oxygen and a transition metal having catalytic activity.

In one embodiment of a typical alloy, the oxygen active metal is at least one metal selected from the group consisting of Group 4A-6A, 3B and 4B metals and has a catalytic activity transition metal Includes a combination of these two metals, which is at least one transition metal selected from the group consisting of Group 8 to Group 11 transition metals.
One embodiment of a typical alloy is a combination of a Group 4A-6A metal as a metal active to oxygen and a transition metal of Groups 7-10 as a transition metal having catalytic activity. Or a combination of a Group 4A-5A metal as a metal active to oxygen and a transition metal of Groups 8-10 as a transition metal having catalytic activity, or a metal active to oxygen An alloy containing a combination of a transition metal selected from Group 4A to Group 5A metals and a transition metal having catalytic activity of Group 10 may be mentioned.
One embodiment of a specific alloy is a combination of metals wherein the metal active against oxygen is titanium (Ti) and the transition metal having catalytic activity is palladium (Pd) or platinum (Pt). Alloy containing.

The composition ratio of the two kinds of metals, that is, the metal active in the alloy with respect to oxygen and the transition metal having catalytic activity, may be any ratio, and the blending amount of the raw material single metal during the production of the alloy is adjusted. Thus, the content ratio in the obtained alloy can be appropriately changed. For example, the transition metal having catalytic activity is preferably about 15 mol% or less, more preferably about 10 mol% or less with respect to the metal active with respect to oxygen. For example, a ratio of about 0.01 to 15 mol%, a ratio of about 0.1 to 10 mol% can be mentioned, and the ratio is typically about 1 mol%. In addition, for example, when the compounding amount of palladium (Pd) exceeds 15 mol%, there is a report that Pd clusters are easily formed and the yield of the product is reduced (Liang-Shu Zhong, Jin-Song Hu, Zhi -Min Cui, Li-Jun Wan, Wei-Guo Song; In-Situ Loading of Noble Metal Nanoparticles on Hydroxyl-Group-Rich Titania Precursor and Their Catalytic Applications, Chemistry of Materials 19 (2007) 4557-4562). Therefore, a transition metal having catalytic activity forms a cluster when the blending ratio is large, and the transition metal having catalytic activity is relatively expensive, so that the content is preferably small. An alloy comprising 99 mol% of a metal active with respect to oxygen (abbreviated as “M”) and 1 mol% (x = 0.01) of a transition metal having a catalytic activity (abbreviated as “N”) Is also referred to as M _0.99 N _0.01 . The X-ray diffraction profile of the alloy-containing composite of the present invention (Ti _0.99 Pd _0.01 ) is shown in FIG.

  The term “zero (0) valent metal atom of transition metal having catalytic activity” means that the valence of the transition metal having catalytic activity is zero. It was confirmed by X-ray photoelectron spectroscopy that the valence was zero (0). Zero-valent transition metal atoms alloy with titanium as they move into the composite. The zero (0) valent metal atoms of the transition metal having catalytic activity are not physically adsorbed in the oxide film, but are uniformly mixed.

The term “oxide film formed from a metal active against oxygen” means an oxide film derived from a metal active against oxygen. It is known to form oxide films for Group 4A-6A, 3B and 4B metals (Alexander Michaelis; Valve Metal, Si and Ceramic Oxides as Dielectric Films for Passive and Active Electronic Devices, Advances in Electrochemical Science and Engineering, Vol.10 (2008) Chapter 1).
The thickness of the oxide film may vary depending on the conditions of the oxidation treatment when producing the alloy (for example, reaction time, reaction pressure, reaction temperature, etc.). The thickness of the oxide film of the composite of the present invention is usually, for example, about 0.1 nm to about 100 nm, and about 5 nm to about 20 nm, typically about 1 nm to about 20 nm. For example, when natural oxidation treatment was performed, a film having a thickness of about 1 to about 5 nm was formed. Therefore, when an artificial physical or chemical oxidation treatment is performed, the growth of the oxide film is faster than that when a natural oxidation treatment is performed. Therefore, an artificial oxidation treatment or a natural oxidation treatment is performed. The thickness of the oxide film in the composite of the present invention obtained by performing is preferably about 5 nm or more. In order to prevent poisoning of the zero (0) valent metal atom of the catalytically active transition metal mixed in the oxide film, the oxide film preferably has a certain thickness. The growth of the oxide film also depends on the surrounding environment. For example, in the order of inert atmosphere, reduced-pressure atmosphere, dry air, and wet environment, the inert atmosphere may be the slowest film growth and the wet environment may be fast. Generally known.

  Even if the composite of the present invention is physically damaged, a metal active to oxygen constituting the alloy existing therein is oxidized by ambient (for example, atmospheric) oxygen, so that the alloy It is distributed between the oxide film and the zero-valent transition metal element and self-repairs. It was found that the titanium oxide film exhibited a self-healing function quickly.

Next, a method for producing the composite of the present invention will be described.
Although the composite_body | complex of this invention can be manufactured with the following manufacturing method, it is not limited to this. The production method is as follows:
1) An alloy is prepared by dissolving a mixture of a single metal active against oxygen and a single transition metal having catalytic activity;
2) oxidizing the prepared alloy to form an oxide film to obtain a composite; and
3) If necessary, shape the resulting composite into the desired shape.
Including that.

The preparation method of the alloy in step 1) of the production method includes a generally known alloy production method, for example, including, but not limited to, resistance heating melting method, high frequency induction heating melting method, arc melting method and the like. At the time of alloy preparation, the ambient atmosphere may be an inert atmosphere (for example, argon, helium), a reduced pressure atmosphere, dry air, or a humid environment. Is fast.
Further, the alloy is prepared by using an apparatus usually used at the time of manufacturing the alloy in a normal pressure or reduced pressure atmosphere at a temperature equal to or higher than the melting point of the alloy constituent element. Examples of the equipment include an electric furnace, a high-frequency furnace, and the like, and specific examples include a non-consumable tungsten argon arc melting furnace (for example, manufactured by Daia Vacuum Co., Ltd.), but are not limited thereto.

  In step 2), the oxidation treatment is performed using an oxygen donor, and the oxygen donor may be either the oxygen donor reagent (for example, hydrogen peroxide or nitric acid) or oxygen molecules in the air. As a simple method, an oxidation treatment (natural oxidation treatment) may be performed by leaving the complex in the air.

  In step 3), the surface of the composite obtained by a polishing machine is polished as necessary. As a polishing method, a mirror surface can be finished using, for example, diamond paste or colloidal silica. As a result, the surface area of the composite can be used more efficiently, and the reaction can be prevented from proceeding starting from defects on the alloy surface. The complex treated and prepared at a high temperature is kept in the desiccator for a certain period of time in order to stabilize the oxidation state of the complex and prevent the complex from being poisoned. Hold for several hours to several days (typically 1 to 3 days, eg 1 day).

  In step 4), if necessary, the composite may be molded into a desired shape. For example, it is molded into a desired shape using an apparatus generally known in the molding of alloys. For example, a vertical milling machine, a lathe or the like can be used as a molding device to mold into a flake shape, a ribbon shape, or an ingot shape, but is not limited thereto.

(Catalytic use of composite)
In addition, a method for using the composite of the present invention will be described. For example, the usage in organic synthesis is mentioned. The organic synthesis is not particularly limited as long as it is an organic synthesis reaction known to be produced by a transition metal having catalytic activity. A typical example is a cross-coupling reaction.

The term “cross-coupling reaction” means a reaction that selectively binds between two different compounds. In particular, the cross-coupling reaction contemplated by the present invention refers to the following formula where the transition metal compound acts catalytically:

Means the reaction indicated by Specifically, reactions between organic halides and terminal alkenes (Mizorogi / Heck reaction), reactions between organic halides and organic zinc compounds (Negishi coupling reaction), organic halides and organic tin compounds, etc. Reaction (Migita, Kosugi, Stille coupling), reaction of organic halides with terminal alkynes (Soto coupling), reaction of organic halides with organic boron compounds (Suzuki / Miyaura coupling), organic Reaction of halides with organic amine compounds (Buchwald / Hartwig reaction), reaction of organic halides with organic magnesium compounds (Kumada / Tamao / Colleu coupling), reaction of organic halides with organosilicon compounds Intended for (Eizan coupling). In particular, the Suzuki-Miyaura coupling is intended.

In one embodiment, the cross-coupling reaction is
Formula: AX
(Where
A is an unsubstituted or substituted aryl group, an unsubstituted or substituted heteroaryl group, or an unsubstituted or substituted alkenyl group; and
X is a halogen, a mesylate group, a tosylate group, a triflate group, or a carboxylic acid halide group)
A compound represented by
Formula: BY
(Where
B is an unsubstituted or substituted aryl group, an unsubstituted or substituted heteroaryl group, an unsubstituted or substituted alkenyl group, or an unsubstituted or substituted alkynyl group;
Y is hydrogen, aryl group, alkoxycarbonyl group, nitro group, formyl group, oxo group, cyano group, amino group, B (OR ¹ ) ₂ , ZnX ¹ , AlR ² ₂ , SnR ³ ₃ , MgX ² , or SiR ⁴ _3, wherein, ^{X 1} and ^{X 2} is halogen and ^{R 1,} R 2, ^{R 3} and ^{R 4} are each independently hydrogen or alkyl)
Is reacted in the presence of a catalyst for cross-coupling reaction containing the complex of the present invention,
Formula: AB
(In the formula, A and B are as described above.)
To obtain a product represented by

In a preferred embodiment, the cross-coupling reaction is
Formula: AX
(Where
A is an unsubstituted or substituted aryl group; and
X is a halogen, a mesylate group, a tosylate group, or a triflate group)
A compound represented by
Formula: BY
(Where
B is an unsubstituted or substituted aryl group;
Y is B (OR ¹ ) ₂ and R ¹ is hydrogen)
Is reacted in the presence of a catalyst for cross-coupling reaction containing the complex of the present invention,
Formula: AB
(In the formula, A and B are as described above.)
To obtain a product represented by

  The term “compound represented by the formula: AX” means one of the reaction substrates that acts as an electrophile in the cross-coupling reaction. Here, the group A is a group having at least one carbon-carbon unsaturated bond, specifically, an unsubstituted or substituted aryl group, an unsubstituted or substituted heteroaryl group, and an unsubstituted or substituted group. Contains an alkenyl group. An unsubstituted or substituted aryl group is preferred. The X group means a group known as a leaving group in the field of organic chemistry. Specifically, halogen (for example, chloro, bromo, iodo), mesylate group (OMs), tosylate group (OTs), or carboxylic acid halide group (for example, carboxylic acid bromide (C (= O) Br, carboxylic acid) Iodide (C (= O) I)), preferably halogen, mesylate group, tosylate group, or triflate group, more preferably halogen, more preferably bromo or iodo, and particularly preferably iodo.

The term “compound represented by the formula: BY” means one of the reaction substrates that acts as a nucleophile in the cross-coupling reaction. Here, the group B is a group having at least one carbon-carbon unsaturated bond, specifically, an unsubstituted or substituted aryl, an unsubstituted or substituted heteroaryl group, an unsubstituted or substituted alkenyl group. And unsubstituted or substituted alkynyl groups. An unsubstituted or substituted aryl group is preferred. Y group is hydrogen, aryl group, alkoxycarbonyl group, nitro group, formyl group, oxo group, cyano group, amino group, B (OR ¹ ) ₂ , ZnX ¹ , AlR ² ₂ , SnR ³ ₃ , MgX ^2. Or SiR ⁴ ₃ and B (OR ¹ ) ₂ (R ¹ is hydrogen) is preferred. Wherein X ¹ and X ² are halogens (chloro, bromo, iodo are preferred, bromo, iodo are more preferred) and R ¹ , R ² , R ³ and R ⁴ are each independently hydrogen or alkyl ( Alkyl having 1 to 6 carbon atoms is preferable, and methyl, ethyl, and t-butyl are more preferable.

  The term “unsubstituted or substituted aryl group” means an aromatic carbocyclic group having 1 to 5 substituents as appropriate. Also included in this definition are polycyclic groups (eg, bicyclic groups) linked in a fused ring fashion. Specific examples include monocyclic aryl groups such as phenyl group, 1-naphthyl group and 2-naphthyl group; bicyclic aryl groups such as phenanthridinyl group, 6-chromanyl group and 5-isoindolyl group. It is done. A phenyl group, a 1-naphthyl group, and a 2-naphthyl group are preferable.

  Here, the substituent may be any group that does not hinder the progress of the cross-coupling reaction, and is known as an electron donating group (for example, amino group, alkyl group, alkoxy group) or electron withdrawing property known in the field of organic chemistry. Any of groups (for example, nitro group, formyl group, oxo group, cyano group, alkoxycarbonyl group) may be used, but an electron donating group is preferable. For example, an alkyl group (for example, an alkyl group having 1 to 6 carbon atoms (for example, a methyl group, an ethyl group)), a halogenated alkyl group (for example, a trifluoromethyl group), a nitro group, a formyl group, an oxo group, Acyl group (eg, acetyl group, propionyl group, butyryl group), amino group (eg, N-methylamino group, N-ethylamino group, N, N-dimethylamino group, N, N-diphenylamino group), hydroxy Group, alkoxy group (for example, methoxy group, ethoxy group), carboxy group, and cyano group. An alkyl group and an alkoxy group are preferred.

  The term “unsubstituted or substituted heteroaryl group” refers to at least one heteroatom selected from a nitrogen atom, an oxygen atom, or a sulfur atom in at least one ring having 1 to 5 substituents as appropriate. Means an aromatic cyclic group. Also included in this definition are polycyclic groups (eg, bicyclic groups) linked in a fused ring fashion. Specific examples include pyrrolyl, pyrazolyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, thiadiazolyl, isothiazolyl, pyridyl, furyl, thienyl, oxadiazolyl, 2-oxaazepinyl, azepinyl, pyrazinyl Group, pyrimidinyl group, pyridazinyl group, triazinyl group, triazolyl group and the like monocyclic heteroaryl group; and benzothiazolyl group, benzoxazolyl group, benzothienyl group, benzofuryl group, quinolinyl group, quinolinyl-N-oxide group, isoquinolinyl group, Benzoimidazolyl group, benzopyranyl group, indolizinyl group, cinnolinyl group, quinoxalinyl group, indazolyl group, pyrrolopyridyl group, furopyridinyl group (for example, furo [2,3-c] pyridinyl group, furo [ 3,1-b] pyridinyl group or furo [2,3-b] pyridinyl group), benzisothiazolyl group, benzisoxazolyl group, benzodiazinyl group, benzothiopyranyl group, benzotriazolyl group, And bicyclic aryl groups such as bicyclic heteroaryl groups such as benzopyrazolyl group, naphthyridinyl group, phthalazinyl group, purinyl group, pyridopyridyl group, quinazolinyl group, thienofuryl group, thienopyridyl group, and thienothienyl group. A pyridyl group is preferred. As defined in the above “unsubstituted or substituted aryl group”, the substituent may be any group that does not hinder the progress of the cross-coupling reaction, and specific examples are as described above.

  The term “unsubstituted or substituted alkenyl group” means a straight, branched or cyclic group having 2 to 12 carbon atoms and at least one double bond, optionally having 1 to 5 substituents. A hydrocarbon group is meant. Specific examples include ethenyl group (vinyl group), 1-propenyl group, 1-butenyl group, 1-pentenyl group, 1,3-dipentenyl group, cyclohexenyl group and the like. An ethenyl group is preferred. As defined in the above “unsubstituted or substituted aryl group”, the substituent may be any group that does not hinder the progress of the cross-coupling reaction, and specific examples are as described above.

  The term “unsubstituted or substituted alkynyl group” refers to a linear or branched hydrocarbon group having 2 to 6 carbon atoms and one triple bond, optionally having 1 to 3 substituents. means. A terminal alkynyl group in which hydrogen on carbon at one end of acetylene is substituted with a group other than hydrogen is preferable. Specific examples include 1-propynyl, 1-butynyl, 3,3-dimethyl-1-butynyl and the like. 1-propynyl is preferred. As defined in the above “unsubstituted or substituted aryl group”, the substituent may be any group that does not hinder the progress of the cross-coupling reaction, and specific examples are as described above.

  The term “alkoxycarbonyl group” means an alkoxycarbonyl group containing an alkyl group having 1 to 12 carbon atoms, preferably 1 to 8 carbon atoms, more preferably 1 to 6 carbon atoms. Specific examples include methoxycarbonyl, ethoxycarbonyl, n-propoxycarbonyl, butoxycarbonyl (n-butoxycarbonyl, iso-butoxycarbonyl, t-butoxycarbonyl), pentyloxycarbonyl, hexyloxycarbonyl and the like. Methoxycarbonyl, ethoxycarbonyl and t-butoxycarbonyl are preferred.

  The cross-coupling reaction is generally performed according to a procedure known as a catalytic cross-coupling reaction as shown in the above formula 1. Specifically, the compound (1) represented by the formula: AX and the compound (2) represented by the formula: BY in the presence of a catalyst containing the alloy-containing composite obtained above. React. Here, depending on the type of the cross-coupling reaction, the reaction is performed in the presence of a base. Bases include organic bases (eg triethylamine, pyridine) or inorganic bases (eg hydroxides (eg sodium hydroxide)), carbonates (eg potassium carbonate), bicarbonates (eg sodium bicarbonate) ).

  A compound (1) represented by the formula: AX and a compound (2) represented by the formula: BY, which are reaction substrates, are either commercially available or a method known in the field of organic chemistry, Or it can manufacture by the method according to these.

  As a reaction solvent for the cross-coupling reaction, an ordinary organic solvent can be used, or a reaction substrate or a base can be used as a solvent. For example, typical reaction solvents include alcoholic organic solvents (eg, methanol, ethanol).

  The compounding ratio of the compound (1) and the compound (2) as the reaction substrate is such that the amount of the compound (2) is equal or excessive based on the compounding amount of the compound (1). For example, the compound (2) is used in an amount of 1.0 to 3.0 equivalents, 1.0 to 2.0 equivalents, preferably 1.2 to 1.5 equivalents.

The amount of the catalyst containing the alloy-containing composite of the present invention is about 10 ⁻¹ to 10 ⁻⁵ mol%, about 10 ⁻¹ to 10 ⁻³ mol%, based on the amount of compound (1) as the reaction substrate, Preferably about 10 ^{< -1} > -10 ^<-2> mol% can be used. In particular, in the case of Suzuki-Miyaura coupling, it can be used at about 10 ⁻¹ to 10 ⁻² mol%, specifically about 0.1 to 1.0 mol%.

  The evaluation as the catalyst of the present invention can be expressed by, for example, the conversion rate to the final product often used in the field of catalytic chemistry. The catalyst of the present invention exhibits a conversion of about 90% or more, about 92% or more, about 94% or more, or about 95% or more, typically about 99% or more. This therefore suggests that little by-product is produced. Also, the yield of the product of the present invention is about 90% or higher, or about 95% or higher, typically about 99% or higher. Therefore, the conversion rate and yield suggest that the coupling reaction of the present invention proceeds extremely efficiently.

  In the case of a normal cross-coupling reaction, generally, the catalyst to be used is exposed to the atmosphere and deactivated, so that reduction treatment of hydrogen gas or the like is required. On the other hand, the catalyst containing the alloy composite of the present invention does not require such reduction treatment because zero (0) -valent transition metal atoms are protected in the oxide film.

  The coupling reaction of the present invention can be carried out at a low temperature (for example, −70 ° C. or lower) to a high temperature (for example, 100 ° C. or higher), and is usually from room temperature to the boiling point of the reaction solvent used, preferably a temperature of 80 or higher. A temperature of 100 ° C. or higher is more preferable.

  The reaction of the present invention can be performed under normal pressure from a normal pressure in a pressurized container (for example, a commercially available container such as a pressure tube), and is usually performed at normal pressure.

  The reaction time of the present invention may vary depending on the reaction conditions such as the solvent used, reaction temperature, etc., but it is completed in several hours to several days, usually about 5 hours to about 3 days, and about 24 hours. preferable.

(Functional material of composite)
Further, the alloy-containing composite of the present invention is difficult to be poisoned because the transition metal element having catalytic activity is mixed in the oxide film, and can maintain the catalytic activity of the transition metal. In addition, since it exhibits self-healing properties, it forms an alloy-containing composite that is stable and can change its shape. Therefore, the composite of the present invention can be used as a functional material for various applications based on the above functions. For example, gas storage and gas separation for gas (eg, nitrogen, hydrogen, carbon monoxide, carbon dioxide, helium, argon); catalyst (eg, heterogeneous catalyst (hydrogenation reaction catalyst, photocatalyst, Kunefener gel condensation) Reaction catalysts)); and devices (eg gas sensor devices, solid electrolytes for fuel cells).

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. Confirmation of the alloy-containing composite and the product of the cross-coupling reaction was performed by analysis of various spectroscopic analyses.

Example 1
Preparation of alloy catalyst Sponge titanium (manufactured by Toho Titanium) with a purity of 99.5% or more is melted at a current of 200 mA or more in a 99.99% or more argon atmosphere using a non-consumable electrode type tungsten arc melting furnace. The titanium ingot was obtained. Pd is weighed so as to have a target composition (1.0 mol% Pd) with respect to the obtained button-shaped ingot, added to the button-shaped titanium ingot obtained previously, and the mixture is again melted with a non-consumable electrode type tungsten arc. It melt | dissolved using the furnace and the button-shaped alloy was obtained. The alloy was cut from the surface using a vertical milling machine and a carbide tool to obtain a flaky alloy catalyst.

(Example 2)
Manufacture of the composite The composite was obtained by utilizing a natural oxide film of titanium. That is, the flaky sample cut with a milling machine was not prepared under an inert atmosphere, but was prepared under the open atmosphere. Then, it was left to stand in a desiccator adjusted to a temperature of 20 ° C. and a humidity of 25% for 1 day or more under dry air to grow a natural oxide film.
The surface of the plate-like alloy is roughly polished using water-resistant abrasive paper (grain size # 150- # 800) and finished to a mirror surface using diamond paste (grain size 1-9 μm) and colloidal silica (grain size 0.04 μm) It was. When finishing to a mirror surface, ultrapure water (Merck Millipore, specific resistance value 18.2 MΩcm ⁻¹ ) is gradually added to colloidal silica for the purpose of preventing residual abrasives and contamination of the spreading liquid, and finally ultrapure water. Only the alloy surface was cleaned. After finishing the mirror surface, it was left in a desiccator for at least one day to promote the growth of a natural oxide film. The structure of the complex was analyzed using an X-ray photoelectron spectrometer (ULVAC Phi, PHI 5000 VersaProbe). As a result, the structure of the composite of the present invention obtained is shown in FIG.

Example 3
Structure of complex The structure of the complex (Ti _0.99 Pd _0.01 ) was analyzed by X-ray diffraction profile. The result is shown in FIG. Due to the valence state of palladium in the titanium oxide, it was found that the outermost surface of the composite was covered with an oxide film only to a certain extent from the surface, and the center inside was a solid alloy metal. In addition, since the inside of the center is an alloy metal, even if the film is temporarily destroyed, the film is repaired immediately (for example, in a few ms).

Moreover, the X-ray photoelectron spectroscopy analysis result of the alloy containing composite_body | complex of this invention was performed. Specifically, sputtering was performed from the surface of the alloy-containing composite of the present invention, and the valence state of the transition metal atoms inside was examined. The transition metal atoms were analyzed for palladium (FIG. 3) and platinum (FIG. 5). In the case of palladium, peaks with binding energies of about 336 and 341 ev suggest the presence of Pd (0). The valence of palladium was all zero from the surface to the inside, and a slight chemical shift was observed due to metal bonding with titanium inside the alloy (FIG. 3). These peaks shifted to a higher energy side as the sputtering time increased, that is, as they moved into the composite. This suggested that palladium was alloyed with titanium (FIG. 3). Further, as the sputtering time of the peak intensity increased, the peak intensity increased. This suggests that the concentration of palladium increases as it moves inward (FIG. 4).
Similarly, in the alloy-containing composite to which platinum was added, a peak having a binding energy of about 71 and 75 ev suggests the presence of Pt (0). As in the case of palladium, these peaks shifted to the high energy side, indicating that platinum is zero-valent and exists on the surface of the alloy-containing composite, and that the central interior is alloyed with titanium (FIG. 5).
Since palladium and platinum are zero-valent, it can be said that the cross-coupling reaction has proceeded.

Example 4
Properties of composites Palladium and platinum are known to act as catalysts for the dissociation of hydrogen molecules. FIG. 6 shows the change in the pressure of the hydrogen gas when the temperature is raised and maintained from room temperature to 400 ° C. in a hydrogen atmosphere. Titanium is known to cause a chemical reaction with hydrogen thermodynamically at normal temperature and atmospheric pressure in an atmosphere of hydrogen, but in the present invention, the surface oxide film is actually a barrier and does not react with hydrogen. Therefore, it was recognized that by adding palladium to titanium, dissociation of hydrogen molecules was promoted by palladium atoms on the alloy surface, and the pressure of hydrogen gas was quickly reduced.

(Example 5)
Cross Coupling Reaction As a representative example of the cross coupling reaction of the present invention, the Suzuki-Miyaura reaction was selected, and the catalytic ability of the alloy-containing composite of the present invention was examined. In addition, abbreviations used in the following examples will be described.
Me represents a methyl group, Et represents an ethyl group, iPr represents an isopropyl group, DMA represents dimethylacetamide, DMF represents dimethylformamide, and THF represents tetrahydrofuran.
The reagents and all starting materials used in the following examples are commercially available and were used without further purification.
A stirrer was placed in a 15 mL pressure tube, 0.024 g of titanium-1.0 mol% palladium alloy obtained in Example 1 (0.5 mmol, 0.005 mmol in terms of Pd), 4-methylphenylboronic acid or phenylboronic acid 0 .75 mmol (0.1020 g) and 0.1382 g (1.0 mmol) of sodium carbonate were added, and the inside of the container was replaced with argon. Next, 0.1020 g (0.5 mmol) of iodobenzene and 2 mL of methanol as a solvent were added and stirred. Then, it heated at 120 degreeC for 24 hours, and reaction was performed.
Quantitative analysis was performed by gas chromatography using an internal standard method (the reference material is tridecane), and as a result, biphenyl or 4-methylbiphenyl as a coupling product was quantitatively obtained. It could be confirmed. The following examination was performed with Ti-0.2 mol% Pd 0.024 g (0.5 mmol, 0.001 mmol in terms of Pd).

Below, the result at the time of changing various reaction conditions of this application reaction is shown. The examination result of reaction conditions is shown.
(Example 5-1)
About the alloy containing composite catalyst of this invention, the case where a hydrogenation reduction process is given and the case where it does not give were compared.


Product mass spectrum (MS): 154.21

  In the table, Pt (Hy) means a catalyst subjected to a hydrogenation treatment. As a result, it was shown that the composite catalyst of the present invention that does not require hydroreduction treatment has high catalytic activity.

(Example 5-2)
The alloy type of the present invention was examined. The substrate was changed to p-tolylboronic acid and examined using various alloys and metal bulks.


Product mass spectrum (MS): 168.23

  As a result, it was shown that the alloy composite catalyst of the present invention showed higher catalytic activity than the case of titanium alone.

(Example 5-3)
The substrate was examined. Specifically, the reaction was carried out with benzene bromide and benzene chloride instead of benzene iodide.

  As a result, it was found that the reaction proceeded slower than iodobenzene, but the reaction proceeded.

(Example 5-4)
The reaction atmosphere was examined. Specifically, the progress of the reaction in the air atmosphere was examined.

  As a result, it was found that even when the reaction was carried out in an air atmosphere, the catalytic reaction proceeded smoothly and the product was given in high yield.

(Example 5-5)
The solvent was examined.

  As a result, it was shown that the reaction proceeds smoothly in the case of MeOH, diethylene glycol, and water.

(Example 5-6)
Base species were examined.

The reaction proceeded smoothly with NaHCO ₃ , Na ₂ CO ₃ , K ₂ CO ₃ , Cs ₂ CO ₃ , K ₃ PO ₄ , and NaOH.

(Example 5-7)
The reaction temperature was examined.

  As a result, it is suggested that a high temperature of 100 ° C. or higher is suitable for proceeding with this reaction.

  The alloy-containing composite obtained by the present invention can be manufactured at a low cost with a low content of transition metal atoms by a very simple manufacturing method, has self-healing properties, and has catalytic activity and selectivity. To provide a high and excellent alloy-containing composite. Further, the obtained alloy-containing composite exhibits excellent activity as a catalyst for cross-coupling reaction, and does not require reduction treatment of hydrogen gas or the like. Furthermore, it is useful as a functional material such as gas storage, gas separation, gas sensor device, or heterogeneous catalyst.

Claims (14)

An alloy composed of a metal active against oxygen and a transition metal having catalytic activity at the center of the composite;
Around the alloy, an oxide film formed from the oxygen-active metal, and a zero (0) valent metal atom of the transition metal having the catalytic activity in the oxide film,
A complex comprising   The composite according to claim 1, wherein the oxygen active metal is at least one transition metal selected from the group consisting of Group 4A-6A, 3B and 4B transition metals.   Metals active against oxygen are titanium (Ti), zirconium (Zr), hafnium (Hf), chromium (Cr), vanadium (V), niobium (Nb), tantalum (Ta), aluminum (Al), The composite according to claim 1, which is at least one transition metal selected from the group consisting of silicon and silicon (Si).   The composite according to any one of claims 1 to 3, wherein the transition metal having catalytic activity is at least one transition metal selected from the group consisting of Group 7 to Group 11 transition metals.   The metal active to oxygen is titanium (Ti), and the transition metal having catalytic activity is palladium (Pd), platinum (Pt), rhodium (Rh), or rhenium (Re). 5. The complex according to any one of 1 to 4.   6. The alloy according to any one of claims 1 to 5, wherein the catalytically active transition metal comprises in the alloy at a ratio of about 0.01 to about 15 mole percent relative to the oxygen active metal. Complex.   The composite according to any one of claims 1 to 6, wherein the oxide film has a thickness of about 5 nm or more.   The composite according to any one of claims 1 to 7, which has self-healing properties. A single elemental transition metal having catalytic activity is blended at a ratio of about 0.01 to about 15 mole percent with respect to a single element active against oxygen, and the mixture is melted to produce an alloy; and
An oxide film is formed by oxidizing the manufactured alloy to obtain a composite.
The manufacturing method of the composite_body | complex of any one of Claims 1 thru | or 8 including this.   A catalyst for cross-coupling reaction, comprising the composite according to any one of claims 1 to 8.   A cross-coupling reaction using the complex according to any one of claims 1 to 8 as a catalyst. Formula: AX
(Where
A is an unsubstituted or substituted aryl group; and
X is a halogen, a mesylate group, a tosylate group, or a triflate group)
A compound represented by
Formula: BY
(Where
B is an unsubstituted or substituted aryl group;
Y is B (OR ¹ ) ₂ and R ¹ is hydrogen)
By reacting with a compound represented by
Formula: AB
(In the formula, A and B are as described above.)
The cross-coupling reaction according to claim 11, comprising obtaining a product represented by:   The catalyst for cross-coupling reaction according to claim 11, which does not require hydrogen reduction treatment of the catalyst.   Use of a composite according to any one of claims 1 to 8 as gas storage, gas separation, gas sensor device or heterogeneous catalyst.