JP5223045B2 - Method for producing diphosphine compound, diphosphine compound produced by this production method and intermediate product - Google Patents

Description

  The present invention relates to a diphosphine compound that is effective for various transition metal catalyzed reactions, a method for producing a diphosphine compound, a diphosphine compound produced by this production method, and an intermediate product.

  It has been reported that phosphine ligands having a sterically crowded structure are effective for various transition metal catalyzed reactions including cross-coupling. It is a field that has been addressed as the most important issue (for example, Patent Documents 1 to 3), and has attracted interest as an important approach to the development of a highly practical catalytic organic conversion process.

JP 2001-253889 A JP 2003-292498 A JP 2003-313194 A

  However, for the synthesis of diphosphine compounds that have two phosphino groups at close positions (especially adjacent positions) and a more complicated steric structure, there are no proposals for synthetic methods that have been effective until now. It has not been.

  The reason for this is due to the crowded steric structure of the diphosphine compound, that is, when two phosphino groups are introduced step by step in the close position, steric hindrance occurs in the introduction of the second phosphino group, The reaction is significantly inhibited.

  Therefore, as a result of intensive studies to solve such problems, the present inventor has obtained an intermediate product by a coupling reaction between a bis (phosphine) boronium salt and an electrophile having at least two electrophilic sites. After the synthesis of, the process for producing the diphosphine compound of the present invention (hereinafter referred to as the present invention method) characterized by treating with a deboronium agent has been completed.

  That is, when producing the diphosphine compound, the present inventor uses a bis (phosphine) boronium salt formed by connecting two phosphino groups with a boronium bridge as a building block, and an electrophile having at least two electrophilic sites. As a result of the coupling reaction, the second phosphine introduction reaction becomes an intramolecular reaction and the reaction proceeds relatively smoothly.

  In addition, it was found that the boronium crosslinking site in the intermediate product after the coupling reaction also functions as a protective group for the phosphino group, which is relatively easily oxidized, and can be easily removed by a simple operation. It is.

  Furthermore, according to the method of the present invention, it has been found that diphosphine compounds having various structures can be easily obtained by combining bis (phosphine) boronium salts having various structures and electrophiles.

  The present invention has been completed on the basis of the above knowledge, and a novel diphosphine compound production method capable of obtaining diphosphine compounds having various structures by a simple synthesis process, a diphosphine compound produced by this production method, and an intermediate The object is to provide a product.

The method of the present invention, which is a means for solving the above problems, is a method for producing a diphosphine compound, which comprises a bis (phosphine) boronium salt and an electrophile having at least two electrophilic sites. An intermediate product is synthesized by a coupling reaction and then treated with a deboronium agent.
Hereinafter, the method of the present invention will be described in detail.

に記す構造を有する化合物、即ち、ある骨格部位Ｙに二つのホスフィノ基が導入された構造を有する化合物である。 The diphosphine compound produced by the method of the present invention is the following general formula (1)

In other words, the compound has a structure in which two phosphino groups are introduced into a certain skeleton Y.

  The skeleton site Y in this diphosphine compound is determined by the structure of an electrophile having at least two electrophilic sites to be described later, and the skeleton structure is not particularly limited.

The substituents R ¹ , R ² , R ³ and R ⁴ on the two phosphorus atoms in this diphosphine compound are determined by the substituents on the two phosphorus atoms in the bis (phosphine) boronium salt described later. There are no particular limitations on the type and structure of the device.

  The method of the present invention has the greatest feature in that a bis (phosphine) boronium salt is used as a building block for the synthesis of the diphosphine compound.

  That is, when two phosphino groups are introduced nucleophilically into a certain skeletal site, if a phosphine borane or phosphine oxide having a large substituent is used as a nucleophile, the reaction does not proceed easily because strong steric hindrance occurs. As for the introduction of alkyl-substituted bulky phosphino groups such as dialkylphosphine, the reaction did not proceed at all, and its synthesis was considered extremely difficult.

  In this regard, in the method of the present invention, since a bis (phosphine) boronium salt is used as a building block for the synthesis of a diphosphine compound, the problem of steric hindrance can be avoided, and thus cannot be achieved conventionally. In addition, many diphosphine compounds can be synthesized.

に記す構造を有する化合物、即ち、二つのホスフィノ基が、ボロニウム部位により架橋された構造を有する化合物である。 Here, the bis (phosphine) boronium salt used in the present invention is the following general formula (2).

In other words, the compound having the structure described below, that is, a compound having a structure in which two phosphino groups are cross-linked by a boronium moiety.

  The method for synthesizing this bis (phosphine) boronium salt is not particularly limited, but the present inventor has two synthetic routes, a symmetric type synthetic route and an asymmetric type synthetic route, as a preferred synthetic method. Heading.

The former symmetric synthesis route is the simplest method for synthesizing bis (phosphine) boronium salts, and various phosphine, monoalkylphosphine, dialkylphosphine, monoarylphosphine, diarylphosphine, alkylarylphosphine, etc. Various phosphine compounds having a substituent are treated with 0.5 equivalent of mono-substituted borane in which hydrogen on borane in borane is mono-substituted with halogen, trifluoromethanesulfonyloxy group or the like (the following general reaction formula (Refer to (4)).

  However, depending on the symmetric synthesis route, it is not possible to synthesize an asymmetric bis (phosphine) boronium salt in which two phosphorus atoms have different substitution patterns.

  Here, when synthesizing an asymmetric bis (phosphine) boronium salt in which two phosphorus atoms have different substitution patterns, the simplest solution is to add two types of phosphine compounds stepwise to a mono-substituted borane. Although the means of adding one equivalent at a time can be mentioned, the present inventor has found the latter asymmetric synthetic route in order to carry out the reaction more clearly.

That is, this asymmetric synthesis route is characterized in that a phosphine compound is treated with a phosphine borane in which a hydrogen group on a boron atom is mono-substituted (see the following general reaction formula (5)), and further. Specifically, by synthesizing phosphine borane by adding a phosphine compound to an excess amount of borane, and using mono-substituted hydrogen on borane in the phosphine borane with halogen, trifluoromethanesulfonyloxy group, etc. Another phosphine compound is treated.

By the way, R ¹ , R ² , R ³ and R ⁴ , which are substituents on the phosphorus atom in the bis (phosphine) boronium salt, are alkyl groups, aryl groups, hydrogen groups, alkoxy groups and other desired types and structures of substitution. The group may be appropriately selected, and is not particularly limited. In general, an alkyl group, an aryl group, an alkoxy group, and the like are preferably selected.

  Specifically, for example, the alkyl group includes a methyl group, an ethyl group, an isopropyl group, a cyclohexyl group, a t-butyl group, an adamantyl group, and a benzyl group for the purpose of variously converting the steric properties of the diphosphine compound of the present invention. Are appropriately selected.

  In addition, in consideration of electronic effects in addition to steric properties, the aryl group may be a phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, 3,5-xylyl group, 3,5 -Diisopropylphenyl group, p-anisyl group, p-trifluoromethylphenyl group, α-naphthyl group, β-naphthyl group and the like, as alkoxy group, methoxy group, ethoxy group, isopropoxy group, t-butoxy group and A phenoxy group or the like is appropriately selected.

  However, high reactivity and stereoselectivity can be obtained in rhodium-catalyzed asymmetric hydrogenation and palladium-catalyzed asymmetric carbon-carbon bond formation reactions using P-chiral phosphines having an asymmetric center on the phosphorus atom. Therefore, the phosphorus atom of the diphosphine compound produced in the method of the present invention preferably has an asymmetric center.

Therefore, in the method of the present invention, at least one phosphorus in the bis (phosphine) boronium salt which is a building block so that at least one (optionally both) phosphorus atoms have an asymmetric center in the produced diphosphine compound. The substituents of R ^{1 to} R ⁴ are preferably selected so that the atom has an asymmetric center.

In addition, in various transition metal catalyzed coupling reactions using monophosphine as a ligand, in order to prevent the catalytically active species from forming a stable dimer during the reaction due to the bulk of the ligand, that is, steric hindrance. Since the reaction is considered to proceed rapidly, the diphosphine compound produced in the method of the present invention also has at least one of the phosphorus atom substituents R ^{1 to} R ⁴ (preferably at least R ¹ and R ^{1). 3} ) and having a bulky structure, for example,
It is preferable to select an alkyl group having a branched structure such as a t-butyl group, an alkyl group having a cyclic structure such as a cyclohexyl group and an adamantyl group, or an aryl group.

Therefore, in the method of the present invention, at least one of the substituents R ^{1 to} R ⁴ of the phosphorus atom in the bis (phosphine) boronium salt which is a building block (preferably at least two of R ¹ and R ³ ). It is preferable to select a bulky structure, for example, an alkyl group having a branched structure such as a t-butyl group, an alkyl group having a cyclic structure such as a cyclohexyl group or an adamantyl group, or an aryl group.

The type and structure of the counter ion “X ⁻ ” in the bis (phosphine) boronium salt are not particularly limited, and various anions can be appropriately selected and used. Halogen anions such as F ⁻ , Cl ⁻ , Br ⁻ and I ⁻ , CF ₃ SO ₃ ⁻ , BF ₄ ⁻ , PF ₆ ⁻ and SbF ₆ ⁻ are preferably used.

In the method of the present invention, first, a coupling reaction between the bis (phosphine) boronium salt and an electrophile having at least two electrophilic sites is performed (preferably under basic conditions) to form a cyclic intermediate product. After obtaining the product, it is treated with a deboronium agent. (See the general reaction formula (6) below)

  That is, since two phosphorus atoms are present as nucleophilic sites in the bis (phosphine) boronium salt, the coupling reaction with an electrophile having at least two electrophilic sites proceeds relatively quickly. In addition, after the coupling between one phosphorus atom and the electrophilic site is established, the coupling on the other side (second stage) is an intramolecular reaction and avoids the inhibition of the reaction due to steric hindrance. It can be done.

  In addition, the boronium bridge | crosslinking site | part in the intermediate product after a coupling reaction can be easily removed by the simple process mentioned later.

  Here, in the method of the present invention, the skeleton site Y in the produced diphosphine compound is determined by the structure of the electrophile having two electrophilic sites, and by appropriately selecting the electrophile. Diphosphine compounds having various skeleton sites can be produced.

For example, when an optically active diol derivative or the like is used as an electrophile, skeletal asymmetry can be introduced (see the following general reaction formula (7)).

Further, for example, when a prochiral 1,2-dicarbonyl compound is used as an electrophile, a stereoselective diphosphine compound can be synthesized (see the general reaction formula (8) below).

Furthermore, it is possible to synthesize orthophenylene-bridged diphosphine by an aromatic nucleophilic substitution reaction and a coupling reaction with a transition metal catalyst (see the following general reaction formula (9)).

  That is, in the method of the present invention, electrophiles having various structures can be used, and diphosphine compounds having any structure can be obtained by combination with the bis (phosphine) boronium salt.

  Therefore, the electrophile used in the method of the present invention is not particularly limited, but specifically, for example, α, α′-dihaloalkane, α, α′-di (sulfonyloxy) alkane, Alkylene sulfate, α, α'-dialkyl-α, α'-dihaloxylene, α, α'-dialkyl-α, α'-di (sulfonyloxy) xylene, α, α'-dialkyl-α, α'-xylyl Rensulphate, diketone, dialdehyde, diimine, α, α'-diketoxylene, α, α'-diformylxylene, α, α'-diiminoxylene, 1,2-dihalobenzene, η6-1,2-dihalobenzene metal Complexes such as 2,2′-dihalo-1,1′-biphenyl or 2,2′-di (sulfonyloxy) -1,1′-biphenyl may be mentioned as suitable examples.

  In various transition metal catalyzed coupling reactions using monophosphine as a ligand, the reaction is promptly performed to prevent a catalytically active species from forming a stable dimer during the reaction due to steric hindrance of the ligand. In addition to the fact that the spatial distance between the ligands approaches, reductive elimination is promoted, or the catalytically active species are forced to become coordination unsaturated. Since each elementary reaction is expected to be accelerated, it is preferable that two phosphino groups are arranged at close positions (particularly adjacent positions) in the diphosphine compound produced in the method of the present invention.

  Therefore, in the method of the present invention, it is preferable to use an electrophile in which two electrophilic sites are arranged in close positions, and in particular, an electrophile in which two electrophilic sites are arranged in adjacent positions. It is more preferable to use an agent.

  As a final step, in the method of the present invention, an intermediate product synthesized by a coupling reaction between the bis (phosphine) boronium salt and an electrophile having at least two electrophilic sites is treated with a deboronium agent. Thus, a diphosphine compound is obtained.

  The boronium crosslinking site in the intermediate product functions as a protecting group for the easily oxidized phosphino group, but this boronium crosslinking site is relatively easy to treat with various deboronium agents such as fluoride anions. It can be removed.

  The deboronium agent is not particularly limited as long as it can remove a boronium crosslinking site in the intermediate product. Generally, hydrogen fluoride, metal fluoride salt, tetrafluoride Butylammonium, pyridinium fluoride, N, N'-diethylaminosulfur trifluoride, tetrabutylammonium bifluoride, tetrabutylammonium triphenyldifluorotin, difluorotrimethylsilyltris (dimethylamino) sulfur, lithium aluminum hydride, bismuth hydride A suitable example is at least one selected from (methoxyethoxy) aluminum.

  The diphosphine compound of the present invention is produced by the above-described method of the present invention and has a unique steric and electronic characteristic in which two phosphorus atoms are close to each other. Realization of highly efficient organic conversion processes that have been difficult to achieve, for example, extension of substrate compatibility in transition metal catalyzed cross-coupling reactions using inert substrates such as alkyl halides and their efficiency, optical activity Enantioselective implementation of reactions by applying diphosphine ligands and highly stereoselective implementation of hydroformylation reactions of olefins with transition metal catalysts are expected, and its application range is very wide. .

に記される環状構造を有するものである。 The intermediate product of the present invention is an intermediate product generated in the method of the present invention, that is, produced by a coupling reaction between a bis (phosphine) boronium salt and an electrophile having at least two electrophilic sites. The following general formula (3)

It has the cyclic structure described in the above.

  This intermediate product is a phosphino group that is easily oxidized in a diphosphine compound protected by a boronium crosslinking site, but this boronium crosslinking site can be removed relatively easily by treatment with a deboronium agent. Therefore, this intermediate product is used as, for example, a form for stable storage and distribution of diphosphine compounds.

  The method of the present invention is a novel method for producing a diphosphine compound having the above-described configuration and capable of obtaining diphosphine compounds having various structures by a simple synthesis process.

  That is, in the present invention, in producing a diphosphine compound, since a bis (phosphine) boronium salt formed by connecting two phosphino groups with a boronium bridge is used, the second-stage phosphine introduction reaction becomes an intramolecular reaction and compared. The reaction proceeds smoothly and smoothly.

  Moreover, the boronium crosslinking site in the intermediate product after the coupling reaction also functions as a protective group for the phosphino group that is relatively easily oxidized, and can be easily removed by a simple operation.

  Furthermore, according to the method of the present invention, diphosphine compounds having various structures can be easily obtained by combining bis (phosphine) boronium salts having various structures and electrophiles. It is also possible to build a library.

  The diphosphine compound of the present invention is produced by the above-described method of the present invention and has a unique steric and electronic characteristic in which two phosphorus atoms are close to each other. Realization of highly efficient organic conversion processes that have been difficult to achieve, for example, extension of substrate compatibility in transition metal catalyzed cross-coupling reactions using inert substrates such as alkyl halides and their efficiency, optical activity Enantioselective implementation of reactions by applying diphosphine ligands and highly stereoselective implementation of hydroformylation reactions of olefins with transition metal catalysts are expected, and its application range is very wide. .

  The intermediate product of the present invention is an intermediate product generated in the method of the present invention, and is produced by a coupling reaction between a bis (phosphine) boronium salt and an electrophile having at least two electrophilic sites. It can be used as an embodiment for stable storage and distribution of the diphosphine compound of the present invention.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

  FIG. 1 exemplarily shows a conventional method in which two phosphino groups are introduced nucleophilically into an electrophile 3 having a certain skeleton Y using a phosphine borane (deprotonated product) 5. That is, when phosphine borane 5 is used as a nucleophile, the reaction does not proceed easily due to strong steric hindrance during the introduction of the second stage phosphino group. In particular, bulky phosphino substituted with alkyl such as dialkylphosphine. Regarding the introduction of the group, the reaction does not proceed at all.

  On the other hand, FIG. 2 illustrates the method of the present invention in which two phosphino groups are introduced nucleophilically into an electrophile 3 having a certain skeleton Y using a bis (phosphine) boronium salt (deprotonated) 2. In other words, since the bis (phosphine) boronium salt 2 is used as a building block for the synthesis of the diphosphine compound 1, the phosphine introduction reaction in the second stage becomes an intramolecular reaction, resulting in steric hindrance. The problem is avoided, so that it is possible to realize the synthesis of many diphosphine compounds 1 that could not be synthesized conventionally.

Table 1 is a table listing examples of various structures of the intermediate product of the present invention and diphosphine compound produced when an electrophile having various structures and a bis (phosphine) boronium salt are subjected to a coupling reaction.

  That is, in the method of the present invention, diphosphine compounds having various structures can be easily obtained by combining bis (phosphine) boronium salts having various structures and electrophiles. A rally can be built.

<Production of [1,2-bis (t-butyl (methyl) phosphino) benzene-κ ² P, P ′] boronium bromide (intermediate product)>
Add 10 mg of bis (t-butyl (methyl) phosphine) boronium bromide and a rotary stirrer to the 10 mL test tube and replace with nitrogen. Add 1 mL of tetrahydrofuran and 50 μL of N, N, N ′, N′-tetramethylethylenediamine. It was.

  The mixture was cooled to −78 ° C. with stirring, and 209 μL of a 1.6 Mn-hexane solution of n-butyllithium was added dropwise. The mixture was stirred at room temperature for 1 hour, then cooled again to −78 ° C. and cooled to o-difluorobenzene. A 2 mL tetrahydrofuran solution of 42 mg tricarbonyl chromium was added.

  Then, after stirring at room temperature for 3 hours, 5 mL of water and 7 mL of dichloromethane were added and stirred vigorously, and after separating the organic layer and the aqueous layer, the aqueous layer was extracted twice with 7 mL of dichloromethane and obtained by adding sodium sulfate. The organic layer was dehydrated.

  This was filtered, and the filtrate was concentrated on a rotary evaporator, and then the resulting residue was purified by silica gel column chromatography (chloroform / methanol = 20/1 → 10/1 → 3/1), and after concentration, yellow Of residue was obtained.

The obtained residue was dissolved in about 3 mL of chloroform and irradiated with sunlight for 24 hours. The obtained green suspension was filtered through Celite, and the filtrate was concentrated using a rotary evaporator to obtain bromide [1,2- Bis (t-butyl (methyl) phosphino) benzene-κ ² P, P ′] boronium 58.8 mg was obtained as a white semi-solid (94% yield).

<Production of [1,2-bis (di-t-butylphosphino) benzene-κ ² P, P ′] boronium bromide (intermediate product)>
154 mg of bis (di-t-butylphosphine) boronium bromide and a rotary stirrer were placed in a 10-mL branch test tube equipped with a Liebig condenser and replaced with nitrogen, and 1 mL of tetrahydrofuran and N, N, N ′, N ′, N ″, N ″ -Hexamethylphosphoric triamide 330 μL was added.

  The mixture was cooled to −78 ° C. with stirring, and 510 μL of a 1.6 Mn-hexane solution of n-butyllithium was added dropwise. The mixture was stirred at room temperature for 1 hour, and then cooled to −78 ° C. again to o-difluorobenzene. A 2 mL tetrahydrofuran solution of 50 mg tricarbonyl chromium was added.

  Thereafter, the temperature was raised to 60 ° C. and stirred for 24 hours, then cooled to room temperature, 5 mL of water and 7 mL of dichloromethane were added, and the mixture was vigorously stirred to separate the organic layer and the aqueous layer, and then the aqueous layer was twice with 7 mL of dichloromethane. The organic layer obtained by extraction and adding sodium sulfate was dehydrated.

This was filtered, and the filtrate was concentrated with a rotary evaporator, and then the resulting residue was purified by silica gel column chromatography (chloroform / methanol = 20/1 → 10/1 → 3/1) and brominated [ Obtained 57.4 mg of 1,2-bis (di-t-butylphosphino) benzene-κ ² P, P ′] boronium as a white solid (62% yield).

<Production of 1,2-bis (di-t-butylphosphino) benzene (bisphosphine compound)>
To a 10 mL branch test tube equipped with a Liebig condenser, 100 mg of [1,2-bis (di-t-butylphosphino) benzene-κ ² P, P ′] boronium bromide obtained in Example 2 and A rotary stirrer was added to replace the nitrogen, and 3 mL of tetrahydrofuran was added.

  While stirring this at room temperature, 1.14 mL of a 1.0 M tetrahydrofuran solution of tetra (n-butyl) ammonium was added dropwise.

  After stirring at 70 ° C. for 48 hours, the mixture was allowed to cool to room temperature and concentrated under reduced pressure. The obtained residue was filtered through about 3 g of basic alumina under a nitrogen stream, and eluted with about 10 mL of diethyl ether.

  The filtrate was concentrated under reduced pressure to obtain 41 mg of 1,2-bis (di-t-butylphosphino) benzene as a colorless solid (yield 64%).

<Production of [1,2-bis (diphenylphosphino) benzene-κ ² P, P ′] boronium bromide (intermediate product)>
A 10-ml branch test tube was charged with 93 mg of bis (diphenylphosphine) boronium bromide and a magnetic stirrer and purged with nitrogen, and 2 ml of tetrahydrofuran and 60 μl of N, N, N ′, N′-tetramethylethylenediamine were added.

  This was cooled to −78 ° C. with stirring, 250 μl of 1.6 Mn-hexane solution of n-butyllithium was added dropwise, and further stirred at room temperature for 30 minutes, and then cooled to −78 ° C. again to o-difluorobenzene trimethyl. A 1 ml tetrahydrofuran solution of 50 mg carbonyl chromium was added.

  After stirring at room temperature for 90 minutes, 4 ml of 1M hydrochloric acid and 4 ml of chloroform were added and vigorously stirred. After separating the organic phase and the aqueous phase, 4 ml of saturated saline was added to the organic phase and stirred vigorously. The phase and the aqueous phase were separated, and the resulting organic phase was dehydrated with sodium sulfate.

  This was filtered, and the filtrate was concentrated with a rotary evaporator. Then, the obtained residue was washed with diethyl ether, and a yellow solid was obtained after drying under reduced pressure.

This was dissolved in about 3 ml of chloroform, and the green suspension obtained by irradiating with light for 3 hours was filtered through Celite. The filtrate was concentrated with a rotary evaporator, and the resulting residue was subjected to silica gel column chromatography (chloroform / Methanol = 20/1 → 10/1 → 5/1), and 72 mg of [1,2-bis (diphenylphosphino) benzene-κ ² P, P ′] boronium bromide was obtained as a white solid (yield 65 %).

FIG. 1 is a schematic diagram showing a conventional method in which two phosphino groups are introduced nucleophilically into a certain skeleton using phosphine borane. FIG. 2 is a schematic view showing the method of the present invention in which two phosphino groups are introduced nucleophilically into a certain skeleton using a bis (phosphine) boronium salt.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Diphosphine compound 2 Bis (phosphine) boronium salt 3 Electrophile 4 Intermediate product 5 Phosphine borane

Claims (6)

The following general formula (1)
[Chemical 1]

A method for producing a diphosphine compound having the following structure, which comprises the following general formula (2)
[Chemical 2]

A bis (phosphine) boronium salt having the following structure and an electrophile having at least two electrophilic sites are coupled to form the following general formula (3):
[Chemical 3]

After the synthesis of an intermediate product having the structure: a method for producing a diphosphine compound, which is treated with a deboronium agent (in the general formulas (1) to (3), R ¹ , R ² , R ³ , R ⁴ is any one substituent selected from an alkyl group, an aryl group, a hydrogen group, or an alkoxy group. In the general formulas (2) and (3), X ⁻ represents F ⁻ , Cl ^−. , Br ⁻ , I ⁻ , CF ₃ SO ₃ ⁻ , BF ₄ ⁻ , PF ₆ ⁻ or SbF ₆ ⁻ , Y in the general formulas (1) and (3) , A skeletal site determined by the structure of the electrophile .   The method for producing a diphosphine compound according to claim 1, wherein at least one phosphorus atom in the bis (phosphine) boronium salt has an asymmetric center. ^{2. At} least one of substituents R ¹ , R ² , R ³ and R ^{4 in} the bis (phosphine) boronium salt is an alkyl group having a branched structure, an alkyl group having a cyclic structure, or an aryl group. Or the manufacturing method of the diphosphine compound of 2.   Substituent R in bis (phosphine) boronium salt ¹ , R ² , R ³ And R ⁴ At least one of which is methyl group, ethyl group, isopropyl group, cyclohexyl group, t-butyl group, adamantyl group, benzyl group, phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, 3, 5-xylyl group, 3,5-diisopropylphenyl group, p-anisyl group, p-trifluoromethylphenyl group, α-naphthyl group, β-naphthyl group, methoxy group, ethoxy group, isopropoxy group, t-butoxy group Or a phenoxy group. The method for producing a diphosphine compound according to any one of claims 1 to 3. The electrophile is α, α′-dihaloalkane, α, α′-di (sulfonyloxy) alkane, alkylene sulfate, α, α′-dialkyl-α, α′-dihaloxylene, α, α′-dialkyl- α, α'-di (sulfonyloxy) xylene, α, α'-dialkyl-α, α'-xylylenesulfate, diketone, dialdehyde, diimine, α, α'-diketoxylene, α, α'-diformyl Xylene, α, α'-diiminoxylene, 1,2-dihalobenzene, η6-1,2-dihalobenzene metal complex, 2,2'-dihalo-1,1'-biphenyl or 2,2'-di (sulfonyloxy) The method for producing a diphosphine compound according to any one of claims 1 to 4 , which is selected from:)-1,1'-biphenyl.   The deboronium agent is hydrogen fluoride, metal fluoride, tetrabutylammonium fluoride, pyridinium fluoride, N, N′-diethylaminosulfur trifluoride, tetrabutylammonium bifluoride, tetrabutylammonium triphenyldifluorotin, The method for producing a diphosphine compound according to any one of claims 1 to 5, wherein the diphosphine compound is at least one selected from difluorotrimethylsilyltris (dimethylamino) sulfur, lithium aluminum hydride, and bis (methoxyethoxy) aluminum hydride. .

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