JP2001270892A - Method for producing ruthenium compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing Hermann's catalyst and an analogues thereof without using Graves's catalyst industrially advantageously. SOLUTION: The Hermann's catalyst or the analogues thereof (1) can be producing via a production process (A) or a production process (B) (wherein R1 is a 1-12C alkyl, a cycloalkyl which may bear a 5-22C substitution or a 6-22C aromatic hydrocarbon which may be substituted; R2 is a halogen atom, a 1-6C alkyl, and the like; (n) is 0 or an integer of 1-5; (r) and (r') are each a 1-12C alkyl, a cycloalkyl which may be substituted or a 6-20C aromatic hydrocarbon group which may be substituted).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a ruthenium compound (dichlororuthenium complex), and more particularly to a method for coordinating ruthenium with a heteroatom-containing carbene compound useful as a metathesis polymerization catalyst for alicyclic olefins. The present invention relates to a method for producing a dichlorobenzylidene ruthenium complex.

[0002]

2. Description of the Related Art Hitherto, many ruthenium complexes in which a neutral electron donor or a heteroatom-containing carbene compound is coordinated to ruthenium as a ligand have been known. It is also known that these ruthenium complexes are useful as ring-opening metathesis polymerization catalysts.

For example, Grubbs et al. Used tristriphenylphosphine ruthenium dichloride as a raw material, reacted with phenyldiazomethane to form bistriphenylphosphine benzylidene ruthenium dichloride, and further exchanged ligand between triphenylphosphine and tricyclohexylphosphine. Bistricyclohexylphosphine benzylidene ruthenium dichloride (so-called "Grubbs catalyst") was produced by the reaction, and it has been reported that this exhibits ring-opening metathesis polymerization catalytic activity (J. Am. Chem. Soc., 118 , 100).
(1996). ).

However, in this production method, since phenyldiazomethane used for introducing a benzylidene group is unstable, it must be prepared immediately before use and reacted at a low temperature. The use of mercury oxide has been pointed out not only in terms of production costs but also in terms of waste disposal.

Therefore, recently, as a method for producing a Grubbs catalyst, (1,5-cyclooctadiene) ruthenium dichloride is used as a raw material, and tricyclohexylphosphine is reacted in a hydrogen atmosphere to produce bis (tricyclohexylphosphine) ruthenium dihydride. A method has been proposed in which phenyldichloromethane is reacted therewith (W
See O98 / 21214. ).

[0006] In addition, (1,5-cyclooctadiene) ruthenium dichloride is used as a raw material, a base is acted on the raw material to form a complex salt, and then acetylenes are reacted to obtain an allene-type carbene complex. A method for producing a target Grubbs catalyst by reacting a large excess of styrene with a benzene is also reported (see EP.0838821).

On the other hand, a ruthenium complex containing a heteroatom-containing carbene compound as a ligand (so-called “Herman catalyst”) reported by Herman et al. Has also attracted attention because of its high ring-opening metathesis polymerization catalytic activity.

This Hermann's catalyst, ie, bis (1,3
-Dialkyl-4-imidazole-2-ylidene) (benzylidene) ruthenium dichloride is produced by a ligand exchange reaction between tricyclohexylphosphine and 1,3-dialkylimidazole carbene using the Grubbs catalyst as a raw material (Angew). Chem.
Int. Egl. , 35 , 2805 (1996). ).

[0009]

As described above, a ruthenium complex in which a neutral electron donor or a heteroatom-containing carbene compound is coordinated to ruthenium as a ligand has attracted attention as a ring-opening metasis polymerization catalyst. However, in reality, no satisfactory production method has been established for this product in an industrial sense.

[0010] In particular, in the case of the Hermann catalyst which is known only by a production method via a Grubbs catalyst, it is not easy to prepare the Grubbs catalyst itself as a raw material, and it is necessary to use an expensive tricyclohexylphosphine group as a leaving group. For this reason, there was a problem in its manufacture.

In view of the above-mentioned problems of the prior art, the present invention provides bis (1,3-disubstituted-4-imidazole-2) without using a Grubbs catalyst as a starting material.
-Ylidene) (benzylidene) ruthenium dichloride, bis (1,3-disubstituted imidazolidine-2-ylidene) (benzylidene) ruthenium dichloride, and analogs thereof (hereinafter collectively referred to as "Hellmann-type catalyst") Is provided industrially and advantageously.

[0012]

Means for Solving the Problems In order to solve the above problems, the present inventors have intensively studied a method for producing a Hermann-type catalyst using a relatively inexpensive ruthenium complex having a leaving group as a starting material. The present inventors have found a production method capable of obtaining a product at a high yield and at a low cost, and have completed the present invention.

That is, the present invention firstly comprises a step of subjecting a ruthenium compound represented by the formula (2) and a compound represented by the formula (3) to a metathesis reaction, comprising the step of: A method for producing a ruthenium compound represented by the formula:

In the first aspect of the invention, before the step of subjecting the ruthenium compound represented by the formula (2) and the compound represented by the formula (3) to a metathesis reaction, the compound is represented by the formula (4) It is preferable to have a step of obtaining a ruthenium compound represented by the formula (2) by reacting the ruthenium compound with 1,3-disubstituted imidazole carbene or 1,3-di-substituted imidazolidine carbene.

The present invention secondly comprises a step of reacting a ruthenium compound represented by the formula (5) with a 1,3-disubstituted imidazole carbene or a 1,3-di-substituted imidazolidine carbene. The present invention provides a method for producing the ruthenium compound represented by 1).

In the second invention, before the step of reacting the ruthenium compound represented by formula (5) with 1,3-disubstituted imidazole carbene or 1,3-di-substituted imidazolidine carbene, It is preferable to include a step of obtaining a ruthenium compound represented by the formula (5) by subjecting the compound represented by the formula (4) and the compound represented by the formula (3) to a metathesis reaction.

According to the present invention, the target Hermann-type catalyst can be produced at a higher yield and at lower cost than in the conventional method.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The ruthenium compound represented by the formula (1) can be produced by the following two methods (A) and (B). 1) Manufacturing method (A)

[0019]

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(A) Reaction of a compound represented by the formula (4) → a compound represented by the formula (2) This reaction is carried out by adding a 1,3-disubstituted compound to a ruthenium compound represented by the formula (4). Imidazole carbene or 1,3
Reacting a di-substituted imidazolidine carbene to obtain a compound represented by the formula (2).

In the production method (a), a compound represented by the formula (4) is used as a starting material. In the formula (4), R ¹ represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a t-butyl group, an n-pentyl group, an n-hexyl group, or the like. A cycloalkyl group which may have a substituent having 5 to 22 carbon atoms such as an alkyl group having 1 to 12 carbon atoms, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and a phenyl group, α 6 to 22 carbon atoms such as -naphthyl group, β-naphthyl group, 1-anthranyl group, 2-anthranyl group and 9-anthranyl group.
And an aromatic hydrocarbon group which may have a substituent.

Examples of the substituent for the cycloalkyl group and the aromatic group include an alkyl group such as a nitro group, a methyl group and an ethyl group; a halogen atom such as fluorine, chlorine and bromine; a methoxy group, an ethoxy group and a propoxy group. And an alkoxy group such as an isopropoxy group. Also,
The cycloalkyl group and the aromatic group may have one or a plurality of the same or different substituents at arbitrary positions.

The compound represented by the formula (4) is a known substance and is described, for example, in Chem. Lett. , P67 (199
It can be manufactured and obtained by the method described in 8).

The 1,3-disubstituted imidazole carbene or 1,3-disubstituted imidazolidine carbene to be reacted with the ruthenium compound represented by the formula (4) is 1,3-disubstituted-4-imidazole-2- An ylidene group,
It coordinates to ruthenium as a 1,3-disubstituted imidazolidine-2-ylidene group.

The nitrogen atom (1,3-position) of these carbene
As a substituent bonded to a linear or branched alkyl group having 1 to 12 carbon atoms, a cycloalkyl group which may have a substituent, or a carbon atom having 7 to 2 carbon atoms which may have a substituent.
An aralkyl group having 0 or 6 carbon atoms which may have a substituent;
To 20 aromatic hydrocarbon groups. These substituents may be the same or different, but it is preferable that the 1,3-position substituents are the same from the viewpoint of production easiness, production cost, and the like.

The alkyl group having 1 to 12 carbon atoms includes methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, t-butyl and n-butyl.
Examples include a pentyl group, a neopentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, and an n-dodecyl group.

Examples of the aralkyl group include aralkyl groups having 7 to 20 carbon atoms, such as a benzyl group, a phenethyl group, a 3-phenylpropyl group and an α-methylbenzyl group.

Examples of the cycloalkyl group include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group and a cyclooctyl group.

Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms include a phenyl group, α-naphthyl group, β-naphthyl group, 1-anthranyl group, 2-anthranyl group, and 9-anthranyl group.

The substituents of the cycloalkyl group, aralkyl group and aromatic hydrocarbon group include fluorine,
Examples include a halogen atom such as chlorine and bromine, and a lower alkyl group such as a methyl group and an ethyl group. These may be the same or different and may be substituted plurally.

Among the substituents bonded to the nitrogen atom of these carbene, methyl, ethyl, propyl, isopropyl, cyclopentyl, cyclohexyl, 2,2
A 4,6-trimethylphenyl group and a 2,6-diisopropyl-4-methylphenyl group are preferred.

Specific examples of the imidazole carbene include 1,3-dimethyl-4-imidazole-2-ylidene and 1-ethyl-3-methyl-4-imidazole-2-yl.
Ilidene, 1,3-diethyl-4-imidazole-2-
Ilidene, 1,3-dimethyl-4-imidazole-2-
Ilidene, 1,3-dipropyl-4-imidazole-2
-Ylidene, 1,3-diisopropyl-4-imidazole-2-ylidene, 1,3-dicyclopentyl-4-imidazole-2-ylidene, 1,3-dicyclohexyl-4-imidazole-2-ylidene, 1,3- Di (2,
4,6-trimethylphenyl) -4-imidazole-2
-Ylidene, 1,3-di (2,6-diisopropyl-4
-Methylphenyl) -4-imidazole-2-ylidene and the like.

Specific examples of the imidazolidine carbene include 1,3-dimethylimidazolidin-2-ylidene,
1-ethyl-3-methylimidazolidine-2-ylidene, 1,3-diethylimidazolidine-2-ylidene,
1,3-dimethylimidazolidine-2-ylidene, 1,
3-dipropylimidazolidin-2-ylidene, 1,3
-Diisopropylimidazolidine-2-ylidene, 1,
3-dicyclopentyl imidazolidine-2-ylidene,
1,3-dicyclohexylimidazolidin-2-ylidene, 1,3-di (2,4,6-trimethylphenyl) imidazolidine-2-ylidene, 1,3-di (2,6-diisopropyl-4-methylphenyl) ) Imidazolidine-
2-ylidene and the like.

In the present invention, of these,
-Diethyl-4-imidazole-2-ylidene, 1,3
-Diisopropyl-4-imidazole-2-ylidene,
1,3-dicyclohexyl-4-imidazole-2-ylidene, 1,3-di (2,4,6-trimethylphenyl) -4-imidazole-2-ylidene, 1,3-diethylimidazolidin-2-ylidene, 1,3-diisopropylimidazolidin-2-ylidene, 1,3-dicyclohexylimidazolidin-2-ylidene, 1,3-di (2,4,6-trimethylphenyl) imidazolidin-
2-ylidene is preferred.

The 1,3-disubstituted imidazole carbene or 1,3-disubstituted imidazolidine carbene is obtained by allowing a base to act on the corresponding salt of 1,3-disubstituted imidazole or 1,3-disubstituted imidazolidine. Can be prepared. For example, a method in which sodium hydride or the like is allowed to act in an ammonia solvent of an imidazolium salt or an imidazolidinium salt, or a method in which sodium hydride is caused to act using potassium t-butoxide as a catalyst, is not limited thereto. . Since these carbene are difficult to isolate, they are usually
Store in a solution state and use it for the reaction as it is.

Examples of the salts of 1,3-disubstituted imidazole and 1,3-disubstituted imidazolidine include hydrochlorides, sulfates, nitrates, acetates, perchlorates, tetrafluoroborates and the like. Is mentioned.

These salts can be produced by a known method. Alternatively, it can be produced by a salt exchange reaction using perchloric acid, tetrafluoroboric acid or the like after isolating imidazole or imidazolidine salt.

The solvent used for the reaction between the ruthenium compound represented by the formula (4) and the 1,3-disubstituted imidazole carbene or 1,3-di-substituted imidazolidine carbene may be any solvent that does not react with the reactants. Can be arbitrarily selected. For example, ethers such as diethyl ether, tetrahydrofuran (THF) and 1,2-dimethoxyethane, aromatic hydrocarbons such as benzene, toluene and xylene, and halogenated hydrocarbons such as methylene chloride, chloroform and carbon tetrachloride. Is mentioned.

The amount of 1,3-disubstituted imidazole carbene or 1,3-disubstituted imidazolidine carbene used is sufficient if it is equivalent to the ligand to be exchanged. There is no problem with overuse, but from an economic perspective,
The amount used is preferably 2 to 4 equivalents, more preferably 2 to 2.5 equivalents to ruthenium.

This reaction normally proceeds smoothly at -20 to 60 ° C, preferably at 0 to 50 ° C. The reaction time is usually 10 minutes to 10 hours.

(B) Reaction of the compound represented by the formula (2) → the compound represented by the formula (1) Then, the compound represented by the formula (2) is added to the compound represented by the formula (3). By reacting the styrenes
The compound represented by the formula (1) can be obtained.

In the formula (3), as the substituent R ² ,
Nitro group, fluorine, chlorine, halogen atom such as bromine, methyl group, lower alkyl group such as ethyl group, methoxy group,
Lower alkoxy groups such as ethoxy group, propoxy group and isopropoxy group are exemplified. In addition, n represents 0 or an integer of 1 to 5, and when n represents 2 or more, R ² may be the same or different.

Specific examples of the styrenes represented by the formula (3) include, for example, styrene, 4-chlorostyrene,
Methylstyrene, 3-methylstyrene, 3,5-dimethoxystyrene, 3-nitrostyrene and the like can be mentioned.
In the present invention, among these, styrene is preferred from the viewpoint of availability and production cost.

The amount of styrene used in the reaction is not particularly limited as long as it can undergo a metathesis reaction with the ligand to be exchanged (vinylidene carbene), and is not particularly limited, but is important for improving the yield of the product. It is preferred to add in excess.

The solvent used in this reaction can be arbitrarily selected as long as it does not react with the reactants. Examples thereof include aliphatic hydrocarbons such as n-pentane, n-hexane and n-heptane, and diethyl ether. , THF, 1,2
Ethers such as dimethoxyethane; aromatic hydrocarbons such as benzene, toluene and xylene; and halogenated hydrocarbons such as dichloromethane, chloroform and carbon tetrachloride.

The reaction temperature is not particularly limited as long as the ligand exchange reaction proceeds, but is usually -20 to 60 ° C, preferably 0 to 50 ° C. The reaction time is usually about 10 minutes to 10 hours. 2) Manufacturing method (B)

[0047]

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(A) Reaction of the compound represented by the formula (4) → the compound represented by the formula (5) This reaction is carried out by adding the compound represented by the formula (4) to the compound represented by the formula (3)
By subjecting the styrenes represented by the formula to a metathesis reaction, an intermediate represented by the formula (5) is obtained.

The solvent that can be used in this reaction can be arbitrarily selected as long as it does not react with the reactants, but preferably, n-pentane, n-hexane, n-heptane, n-octane, cyclohexane, etc. Aliphatic hydrocarbons, ethers such as diethyl ether, THF, 1,2-dimethoxyethane, aromatic hydrocarbons such as benzene, toluene and xylene, and halogenated hydrocarbons such as dichloromethane, chloroform and carbon tetrachloride And the like.

The styrenes represented by the formula (3) include
The same as those exemplified in the above-mentioned production method (A) may be mentioned, but styrene is preferably used from the viewpoint of availability and production cost.

The amount of the styrene represented by the formula (3) may be replaced by a (substituted) vinylidene carbene by a metathesis reaction, and is not particularly limited.
In order to improve the yield of the product, it is preferable to add a large excess, preferably at least 5 molar equivalents per 1 mol of the compound represented by the formula (4).

The reaction temperature is usually -20 to 60 ° C, preferably 0 to 50 ° C. The reaction is generally performed for about 10 minutes to 10 hours.

(B) Reaction of the compound represented by the formula (5) → the compound represented by the formula (1) Then, the obtained compound represented by the formula (5) is added with 1,
The compound represented by the formula (1) can be obtained by reacting 3-disubstituted imidazolecarbene or 1,3-disubstituted imidazolidinecarbene.

The solvent used in this reaction can be arbitrarily selected as long as it does not react with the reactants. Examples thereof include ethers such as diethyl ether, THF and 1,2-dimethoxyethane, benzene, toluene xylene and the like. Aromatic hydrocarbons, dichloromethane, chloroform,
Halogenated hydrocarbons such as carbon tetrachloride and the like can be mentioned.

The 1,3-disubstituted imidazole carbene or 1,3-disubstituted imidazolidine carbene used can be obtained from the corresponding salt of 1,3-disubstituted imidazole or 1,3-disubstituted imidazolidine. , (A)
Can be prepared in the same manner as in the case of the above method.

The amount of the 1,3-disubstituted imidazolecarbene or 1,3-disubstituted imidazolidinecarbene used in this reaction is sufficient if it is equivalent to the ligand to be exchanged. Although there is no problem even if it is used in excess, it should be judged from an economic viewpoint, and preferably 2 to 4 equivalents, more preferably 2 to 2.5 equivalents, per 1 mol of the compound represented by the formula (5). .

The reaction temperature is not particularly limited as long as the temperature at which the ligand exchange reaction proceeds, but is usually-
The temperature is 20 to 60C, preferably 0 to 50C. The reaction is usually completed in 10 minutes to 10 hours.

3) Compound represented by the formula (1) The ruthenium compound represented by the above formula (1), which is an object of the present invention, has chlorine or a substituent as a ligand (imidazole carbene or imidazo Lysine carbene),
And a benzylidene group which may have a substituent R ² .

In the formula (1), the substituents of imidazole carbene and imidazolidine carbene and R ² are the same as those described above.

Specific examples of the ruthenium compound represented by the formula (1) include bis (1,3-dimethyl-4-imidazole-2-ylidene) (benzylidene) ruthenium dichloride, bis (1,3-diethyl-4) -Imidazole-2-ylidene) (benzylidene) ruthenium dichloride, bis (1,3-dipropyl-4-imidazole-
2-ylidene) (benzylidene) ruthenium dichloride, bis (1,3-diisopropyl-4-imidazole-2-ylidene) (benzylidene) ruthenium dichloride, bis (1,3-dicyclopentyl-4-imidazole-2-ylidene) ( Benzylidene) ruthenium dichloride, bis (1,3-dicyclohexyl-4-imidazole-2-ylidene) (benzylidene) ruthenium dichloride, bis (1,3-diethyl-4-imidazole-2-ylidene) (4-chlorobenzylidene) ruthenium Dichloride, bis (1,3-diethyl-4-imidazole-2-ylidene) (3-methylbenzylidene) ruthenium dichloride,

Bis (1,3-dimethylimidazolidin-
2-ylidene) (benzylidene) ruthenium dichloride, bis (1,3-diethylimidazolidine-2-ylidene) (benzylidene) ruthenium dichloride, bis (1,3-dipropylimidazolidine-2-ylidene)
(Benzylidene) ruthenium dichloride, bis (1,
3-diisopropylimidazolidine-2-ylidene)
(Benzylidene) ruthenium dichloride, bis (1,
3-dicyclopentyl imidazolidine-2-ylidene)
(Benzylidene) ruthenium dichloride, bis (1,
3-dicyclohexylimidazolidin-2-ylidene)
(Benzylidene) ruthenium dichloride, bis (1,
3-diethylimidazolidin-2-ylidene) (4-chlorobenzylidene) ruthenium dichloride, bis (1,3-diethylimidazolidin-2-ylidene)
(3-methylbenzylidene) ruthenium dichloride,
And the like.

Of these ruthenium compounds, in the present invention, bis (1,3-diethyl-4-imidazole-2-ylidene) (benzylidene) ruthenium dichloride and bis (1,3-diisopropyl-4-imidazole-2) are used. -Ylidene) (benzylidene) ruthenium dichloride, bis (1,3-dicyclohexyl-4-imidazole-2-ylidene) (benzylidene) ruthenium dichloride,

Bis (1,3-diethylimidazolidine-
2-ylidene) (benzylidene) ruthenium dichloride, bis (1,3-diisopropylimidazolidine-2)
-Ylidene) (benzylidene) ruthenium dichloride, bis (1,3-dicyclohexylimididazolidine)
Particularly preferred is 2-ylidene) (benzylidene) ruthenium dichloride.

4) Polymerization Catalyst The compound represented by the above formula (1) of the present invention is useful as a catalyst for the metathesis polymerization of alicyclic olefins. When the alicyclic olefin is subjected to metathesis polymerization, the amount of the compound represented by the formula (1) is usually about 0.0001 to 1 mol% based on 1 mol of the alicyclic olefin.

The alicyclic olefin used in the polymerization is not particularly limited as long as it can be polymerized. For example, cyclobutene, cyclopentene, cyclopentadiene, norbornene, methylnorbornene, ethylnorbornene, dicyclopentadiene, Cyclic hydrocarbons such as tetracyclodecene, methyltetracyclodecene, ethyltetracyclodecene, ethylidenetetracyclodecene, cyclooctene, norbornene carboxylic acid,
Examples include norbornene carboxylic anhydride, norbornene carboxylic acid methyl ester, norbornene methanol, norbornene dimethanol, and tricyclodecyl methacrylate.

The solvent used in the polymerization is not particularly limited, and examples thereof include aliphatic hydrocarbons such as n-pentane, n-hexane and n-heptane, benzene, toluene, xylene, 1,2-diene. Aromatic hydrocarbons such as chlorobenzene, diethyl ether, THF, 1,
Examples thereof include a hetero atom-containing hydrocarbon such as 2-dimethoxyethane. Of these, hexane, cyclohexane, methylcyclohexane, octane, toluene, xylenes and the like are preferred from the viewpoints of boiling point and toxicity.

The reaction temperature may be any temperature generally used industrially, and for example, a range of 0 ° C. to 200 ° C. is recommended. The temperature is more preferably from 20C to 150C. Further, the catalyst activity does not decrease even in a low temperature range of 20 to 60 ° C.

The reaction time may be within the range usually used industrially, and for example, 30 minutes to 24 hours is recommended. The time is preferably 1 hour to 12 hours, but is specifically determined from productivity and the like.

The polymer obtained by subjecting the monomer exemplified above to metathesis polymerization using the ruthenium compound represented by the formula (1) of the present invention as a polymerization catalyst has a high cis content of 30% or more. , Cyclohexane, methylcyclohexane, octane, toluene, xylene, THF,
It is soluble in various medium-polarity and low-polarity organic solvents such as methylene chloride, chloroform, carbon tetrachloride, and chlorobenzene. Here, the “cis content” indicates the ratio of the cis structure of the main chain double bond of the metathesis polymer.

[0070]

Next, the present invention will be described in more detail by way of examples.

Example 1 Synthesis of bis (1,3-diisopropyl-4-imidazole-2-ylidene) benzylidene ruthenium dichloride (1)

(1) Preparation of 1,3-diisopropylimidazole carbene solution 4.5 g (0.15 mol) of paraformaldehyde was suspended in 25 ml of toluene, and 8.9 g (0.15 mol) of isopropylamine was added to this suspension. The solution was added dropwise over 20 minutes while cooling with water so that the temperature in the reaction system did not exceed 30 ° C. After the addition, the mixture was further stirred for 10 minutes. The reaction mixture was cooled on ice to 5 ° C., and 8.9 g of isopropylamine (0.1 g
(5 mol) was added in 15 minutes. After stirring for 5 minutes, 25 ml (0.15 mol) of 6N HCl was added over 20 minutes.

Next, the temperature of the reaction solution was raised to 22 ° C., and 21.8 g (0.1%) of a 40% aqueous glyoxal solution was added thereto.
5 mol) in 10 minutes. After stirring for 1 hour (the solution turned pale yellow), 25 ml of toluene was added, and De was added.
Water was removed by azeotropic distillation using an-Stark trap (the solution turned reddish brown). After confirming that the distilled toluene became transparent, the reaction was terminated. The solvent was distilled off from the reaction mixture under reduced pressure to obtain 31.8 g (100% yield) of 1,3-diisopropylimidazolium chloride as a reddish brown viscous liquid. In addition, about 5
Crystallization was performed by adding 0 ml of acetone. The obtained crystals were collected by filtration, washed with acetone, and dried under vacuum to obtain 10.0 g (0.053 mol, 35% yield) of brass powdery crystals.

¹ H-NMR (δ ppm, D ₂ O):
8, 7.55, 4.6, 1.5

The 1,3-diisopropylimidazolium chloride (0.94 g, 5 mmol) obtained above was suspended in anhydrous THF (20 ml), and NaH (O
ilfree, 180 mg, 7.5 mmol). The mixture was cooled to −60 ° C., ammonia (50 ml) was introduced into the reaction system in about 10 minutes, and the mixture was further stirred for 2 hours while maintaining the reaction temperature at −40 ° C. NaCl was precipitated with the progress of the reaction. After the completion of the reaction, the reaction system was returned to room temperature, and ammonia was removed. The reaction mixture was filtered under reduced pressure using Celite, and the Celite was washed with toluene.
The filtrate was collected and THF was distilled off under reduced pressure. Toluene was added to the obtained residue to prepare a 0.2 mmol / ml carbene solution (hereinafter, this carbene solution is referred to as “carbene solution”).

(2) Bis (1,3-diisopropyl-4)
Synthesis of -imidazole-2-ylidene) vinylidene ruthenium dichloride

[0077]

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Bis (triphenylphosphine) ruthenium dichloride (1 g, 1.04 mmol) was dissolved in 50 ml of benzene, and phenylacetylene (1 m
1,9 mmol) and stirred at room temperature for 24 hours. The insolubles were removed by filtration, and the filtrate was concentrated under reduced pressure. The obtained residue was crystallized by adding pentane to obtain bistriphenylphosphine (phenylvinylidene) ruthenium dichloride (0.50 g, 0.63 mmol, yield 60%). This was dissolved in 25 ml of toluene, and 8 ml of the previously prepared carbene solution (0.2 mmol / ml) (1.
6 mmol) was added at room temperature. After stirring at room temperature for 1 hour, the solvent was distilled off under reduced pressure. The obtained crude product was recrystallized from toluene / pentane to give bis (1,3-diisopropyl-4-imidazole-2-ylidene) (phenylvinylidene) ruthenium dichloride (0.25 g, 0.1 g).
44 mmol, yield 70%).

Then, 0.25 g of the obtained bis (1,3-diisopropyl-4-imidazole-2-ylidene) (phenylvinylidene) ruthenium dichloride was dissolved in 10 ml of toluene, and styrene (2 ml, 17.5 m) was dissolved.
mol), and the mixture was stirred at room temperature for 3 hours.

After the solvent was distilled off from the reaction mixture under reduced pressure, the obtained residue was dissolved in 1 ml of methylene chloride, and pentane 2
0 ml was added to precipitate crystals, and the precipitated crystals were collected by filtration.
This operation was repeated twice to obtain the desired product.

¹ H-NMR (δ ppm, CDCl ₃ ): 2
0.5, 8.4, 7.7, 7.3, 7.2, 7.0

Example 2 Synthesis of bis (1,3-diisopropyl-4-imidazole-2-ylidene) benzylidene ruthenium dichloride (2)

[0083]

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Bistriphenylphosphine (phenylvinylidene) ruthenium dichloride (0.50 g, 0.1 g)
63 mmol) was dissolved in 10 ml of toluene, styrene (2 ml, 17.5 mmol) was added, and the mixture was stirred at room temperature for 3 hours. After evaporating the solvent and excess styrene from the reaction mixture under reduced pressure, the obtained residue was dissolved in 1 ml of methylene chloride, crystallized by adding 20 ml of pentane, and the precipitated crystals were collected by filtration. This operation was repeated twice to obtain 0.37 g of the target bistriphenylphosphine (benzylidene) ruthenium dichloride. 75% yield

0.37 g of the obtained bistriphenylphosphine (benzylidene) ruthenium dichloride was dissolved in 20 ml of toluene, and 8 ml (1.6 mmol) of the carbene solution (0.2 mmol / ml) prepared in Example 1 was dissolved.
Was added at room temperature. After stirring at room temperature for 1 hour, the solvent was distilled off under reduced pressure. The target product was obtained by recrystallizing the obtained crude product with toluene / pentane.

¹ H-NMR (δ ppm, CDCl ₃ ): 2
0.5, 8.4, 7.7, 7.3, 7.2, 7.0

Reference Example Synthesis of bis (1,3-diisopropyl-4-imidazole-2-ylidene) benzylidene ruthenium dichloride (produced by a conventional method)

[0088]

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Wherein COD is 1,5-cyclooctadiene, Pcy ₃ is tricyclohexylphosphine,
x represents an integer of 2 or more. ) (COD) RuCl ₂ (6 g, 21.4 mmol), tricyclohexylphosphine (12 g, 42.9 mmol)
l) and sodium hydroxide (7.2 g) were suspended in 250 ml of degassed sec-butyl alcohol, and the suspension was reacted at 80 ° C. under hydrogen pressure overnight, and then returned to room temperature. Water (30 ml) was added to the reaction solution to precipitate crystals, and the precipitated crystals were collected by filtration. The crystals obtained by filtration are washed with water (30
ml) and washed twice with methanol (20 ml).
Washed twice. This was dried under a hydrogen atmosphere to obtain 11.8 g (83% yield) of pale yellow crystals of bistricyclohexylphosphine ruthenium hydride.

Next, 1 g (1.5 mmol) of bistricyclohexylphosphine ruthenium hydride was dissolved in 40 ml of pentane, and cyclohexene (1.5
ml, 14.8 mmol) and stirred at room temperature for 1 hour. The reaction solution was concentrated under reduced pressure, and pentane and α, α-phenyldichloromethane (0.4 ml, 3 m
mol) was added. The reaction turned red. After stirring the reaction mixture for 45 minutes, the solvent was distilled off under reduced pressure. The obtained crude product was washed three times with cold methanol (10 ml) to obtain 0.75 g of bistricyclohexylphosphine benzylidene ruthenium dichloride as purple crystals.
I got Yield 61%.

¹ H-NMR (δ ppm, CDCl ₃ ): 2
0.0, 8.5, 7.55, 7.35

The obtained bistricyclohexylphosphine benzylidene ruthenium dichloride (1.0 mmol
l) was dissolved in 20 ml of toluene, and a carbene solution (2.2 mmol / 5) prepared in the same manner as in Example 1 was added thereto.
ml) and stirred at room temperature for 45 minutes. After completion of the reaction, the reaction solution was filtered, and the filtrate was concentrated to 2 ml. The obtained concentrated solution was crystallized by adding pentane (20 ml), and the crystals were collected by filtration and recrystallized from toluene and pentane. 80% yield

¹ H-NMR (δ ppm, CDCl ₃ ): 2
0.5, 8.4, 7.7, 7.3, 7.2, 7.0

[0094]

As described above, according to the present invention, a Hermann-type catalyst can be produced at a higher yield and at lower cost than in the conventional method.

Continued on front page F-term (reference) 4H050 AB40 BB11 BB12 BB15 BB19 WB11 WB14 WB21 4J032 CA23 CA25 CA28 CA34 CA35 CA36 CA38 CA43 CA45 CD02 CE03

Claims (4)

[Claims] (1) Formula (2) (Wherein, R ¹ represents an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group which may have a substituent having 5 to 22 carbon atoms, or an aromatic hydrocarbon group having 6 to 22 carbon atoms. ,
L and L 'are the same or different and each represents 1,3-disubstituted-
Represents a 4-imidazole-2-ylidene group or a 1,3-disubstituted imidazolidine-2-ylidene group. A) a ruthenium compound represented by the formula (3): (Wherein, R ² represents a nitro group, a halogen atom, an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms, and n represents an integer of 0 or 1 to 5). Having a step of subjecting the compound to be subjected to a metathesis reaction to a compound represented by the formula (1): (Wherein, L, L ′, R ² and n have the same meanings as described above). 2. Prior to the step of subjecting the ruthenium compound represented by the formula (2) and the compound represented by the formula (3) to a metathesis reaction, the compound represented by the formula (4): (Wherein, R ¹ has the same meaning as described above), and 1,3-disubstituted imidazole carbene or 1,3-di-substituted imidazolidine carbene is reacted with a ruthenium compound represented by the formula (2). ) (In the formula, R ¹ , L and L ′ represent the same meaning as described above.)
The method for producing a ruthenium compound according to claim 1, comprising a step of obtaining a ruthenium compound represented by the following formula: (3) Formula (5) (Wherein, R ² and n represent the same meaning as described above) with a 1,3-disubstituted imidazole carbene or 1,3-di-substituted imidazolidine carbene. , Formula (1) (Wherein, L, L ′, R ² and n have the same meanings as described above). 4. A ruthenium compound represented by the formula (5), wherein 1,3-disubstituted imidazole carbene or 1,3
-Before the step of reacting the di-substituted imidazolidine carbene, the compound of formula (4) (Wherein, R ¹ has the same meaning as described above) and a compound represented by the formula (3): (Wherein R ² and n represent the same meaning as described above) by a metathesis reaction with a compound represented by the following formula:
Formula (5) The method for producing a ruthenium compound according to claim 3, comprising a step of obtaining a ruthenium compound represented by the formula (wherein, R ² and n represent the same meaning as described above).