JP2001122885A - Ruthenium complex, method for producing the complex, polymerization catalyst and method for producing cyclic olefin polymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new ruthenium carbene complex by a simple preparation method, useful as a catalyst for a metathesis polymerization for a cyclic olefin. SOLUTION: This new ruthenium carbene complex contains three imidazole carbenes and two chlorine atoms as ligands. The ruthenium carbene complex is useful as a polymerization catalyst for a cyclic olefin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel ruthenium carbene complex, a method for producing the same, a polymerization catalyst comprising the complex, and a method for producing a cyclic olefin polymer.
More specifically, the present invention relates to a novel ruthenium carbene complex having imidazole carbene as a ligand, a method for producing the complex, a polymerization catalyst comprising the complex, and a method for producing a cyclic olefin polymer by metathesis polymerization using the catalyst.

[0002]

2. Description of the Related Art Conventionally, as a catalyst for metathesis polymerization of cyclic olefins, a composite catalyst system mainly comprising a compound containing a transition metal such as tungsten or molybdenum has been mainly used. Also, recently, so-called “metal carbene complexes” in which various carbene are coordinated to osmium or ruthenium have been attracting attention as stable catalysts having low sensitivity to oxygen and moisture.

For example, Grubbs et al. Have reported that a ruthenium carbene complex represented by the following formula 4 in which two phosphines having a bulky alkyl group or an aryl group such as tricyclohexylphosphine is coordinated is norbornene, tetracyclododecene (TCD) Have high metathesis polymerization activity even for cyclic olefins such as dicyclopentadiene (DCPD) (J.A.).
m. Chem. Soc. , 1996, 118, 10
Page 0).

[0004]

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(In the formula 4, R is a cycloalkyl group or a phenyl group, and Ph is a phenyl group.) Herrmann et al. Disclose the bulky phosphine in the ruthenium carbene complex represented by the above formula 4 with diisopropylimidazole. It has been reported that a ruthenium carbene complex represented by the following formula 5 was synthesized instead of carbene, and that this compound was a highly active metathesis catalyst for the polymerization of cyclic olefins, similarly to the catalyst of Grubbs et al. (Angew) Chem.Int.Engl.19
1996, 35, 2805).

[0006]

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(In the formula 5, iPr is an isopropyl group, Ph
Is a phenyl group. By the way, the catalyst reported by Grubbs et al. Generally causes metathesis polymerization of cyclic olefins with high activity.
It is known that the resulting polymer has a specific trans structure. Therefore, as a cyclic olefin, DCPD
Polymers obtained from monomers having high symmetry, such as TCD and TCD, are insoluble in many organic solvents and precipitate from the solvent during the polymerization process, which poses a problem in industrial production. In the catalyst reported by Herrmann et al., The obtained polymer is soluble in an organic solvent because it contains about 25% of a cis structure. However, the catalytic activity greatly depends on the polymerization temperature, and when the temperature is lowered, there is a problem that the polymerization activity is remarkably reduced. It is considered that these catalysts cause a metathesis reaction to proceed when the benzylidene carbene and the double bond of the monomer in the structure have a cyclobutene structure. The ruthenium carbene complex represented by the above formula (Grubbs catalyst) and the ruthenium carbene complex represented by the above formula (Her)
rmann catalysts) also had problems with their method of preparation. That is, the Grubbs catalyst generally comprises (i) tristriphenylphosphine ruthenium dichloride (PP
h ₃ ) ₃ RuCl ₂ is reacted with phenyldiazomethane at an extremely low temperature to obtain bistriphenylphosphine benzylidene ruthenium dichloride, and (ii) phosphine exchange is performed by adding tricyclophosphine thereto (J. Am. Che.
m. Soc. , 1996, 118, 100-110.
P.) Or (i) dichloro (1,5-cyclooctadiene) is added with an organic base to form a salt, and then tricyclohexylphosphine is added to perform ligand exchange, and (ii) the organic base is removed. Further, it is prepared by a three-step method (JP-A-10-180114) in which acetylenes are added to give a vinylidene-type carbene, and (iii) an excess of styrene is added to give a benzylidene carbene by a metathesis reaction. Her
The rmann catalyst is prepared by further adding a step of treating the Grubbs catalyst with imidazole carbene. The methods for preparing these catalysts have problems such as a long number of steps and unstable reaction reagents. On the other hand, a catalyst composed of a ruthenium complex having no benzylidenecarbene,
There is a problem that the metathesis polymerization activity is very low.

[0008]

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, an object of the present invention is to provide a novel ruthenium carbene complex which is simple to prepare and is useful as a metathesis polymerization catalyst. It is to provide a manufacturing method which is advantageous to the above. Another object of the present invention is to provide a novel metathesis polymerization catalyst capable of producing a cyclic olefin polymer soluble in an organic solvent, and a method for producing a cyclic olefin polymer using the metathesis polymerization catalyst.

[0009]

Means for Solving the Problems The present inventors have synthesized various ruthenium carbene complexes, evaluated their metathesis polymerization activity, and conducted intensive studies on the solubility of the obtained polymers in organic solvents. As a result, the specific ruthenium carbene complex coordinated by three imidazole carbene is a novel compound and can be produced industrially advantageously; and further, when this ruthenium carbene complex is used as a polymerization catalyst for cyclic olefins, Completed the present invention by finding that a cyclic olefin polymer exhibiting good polymerization activity and having good solubility in organic solvents can be obtained as compared with a ruthenium carbene complex proposed as a metathesis polymerization catalyst for cyclic olefins. I came to. Thus, according to the present invention, the following formula 1

[0010]

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(In the formula 1, R independently represents hydrogen or a hydrocarbon group having 1 to 12 carbon atoms, and the hydrocarbon group may be substituted with a halogen atom.) A complex is provided. Further, according to the present invention, a ruthenium complex represented by the following formula (2) is treated with an imidazole carbene represented by the following formula (3) and subjected to an exchange reaction between phosphine and imidazole carbene. A method for producing a ruthenium carbene complex is provided.

[0012]

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In the formula (2), R's independently of each other have 1 carbon atom.
And -12 hydrocarbon groups.

[0014]

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In the formula 3, R is the same as R in the formula 1. Further, according to the present invention, there is provided a polymerization catalyst comprising the ruthenium carbene complex represented by the above formula 1. Further, according to the present invention, there is provided a method for producing a polymer, comprising subjecting a cyclic olefin to metathesis polymerization in the presence of the catalyst represented by the above formula (1).

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Ruthenium Carbene Complex The ruthenium carbene complex of the present invention is represented by the above formula (1). Hereinafter, the components of the complex will be specifically described. The central metal is ruthenium to which chlorine and an imidazole carbene having a substituent R coordinate as a ligand (ligand).

The substituents R of the imidazole carbene each independently represent a hydrocarbon group having 1 to 12 carbon atoms, and the hydrocarbon group is usually an alkyl group having 1 to 12 carbon atoms and a hydrocarbon group having 2 to 12 carbon atoms. It is selected from the group consisting of an alkenyl group, a cycloalkyl group having 3 to 12 carbon atoms, a cycloalkenyl group having 3 to 12 carbon atoms, and an aryl group having 6 to 12 carbon atoms. Among these, an alkyl group having 1 to 12 carbon atoms and a cycloalkyl group having 3 to 12 carbon atoms are preferable. Specific examples of the hydrocarbon include an alkyl group such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, and hexyl; a cycloalkyl group such as cyclopentyl and cyclohexyl; and an aryl group such as phenyl and tolyl. Among them, methyl group,
Ethyl, propyl, isopropyl, cyclopentyl and cyclohexyl are preferred. The hydrocarbon group may be substituted with a halogen atom, and the halogen atom is not particularly limited, but chlorine is preferable.

Specific examples of imidazole carbene include:
Imidazole, N-methylimidazole, N-ethylimidazole, N, N′-dimethylimidazole, N-ethyl-N′-methylimidazole, N, N′-diethylimidazole, N, N′-dipropylimidazole, N,
N'-diisopropylimidazole, N, N'-dicyclopentylimidazole and N, N'-dicyclohexylimidazole. Of these, N,
N′-dimethylimidazole, N-ethyl-N′-methylimidazole, N, N′-diethylimidazole, N,
N'-dipropylimidazole, N, N'-diisopropylimidazole, N, N'-dicyclopentylimidazole and N, N'-dicyclohexylimidazole are preferred, and N, N'-diethylimidazole, N, N'-
Diisopropylimidazole and N, N'-dicyclohexylimidazole are more preferred. The three imidazolecarbenes coordinated with ruthenium may have the same structure or different structures, but preferably have the same structure.

Preferred specific examples of the ruthenium carbene complex represented by the formula 1 include tris (N, N'-dimethylimidazoleylidene) ruthenium dichloride, tris (N, N'-diethylimidazoleylidene) ruthenium dichloride, tris ( N, N'-dipropylimidazoleylidene) ruthenium dichloride, tris (N, N'-diisopropylimidazoleylidene) ruthenium dichloride, tris (N, N'-dicyclopentylimidazoleylidene) ruthenium dichloride, tris (N, N '-Dicyclohexylpentylimidazoleylidene) ruthenium dichloride, among which tris (N, N'-diethylimidazoleylidene) ruthenium dichloride, tris (N, N'-diisopropylimida) Ruiriden) ruthenium dichloride, tris (N, N'-dicyclohexyl-pentyl-imidazole-ylidene) ruthenium dichloride is more preferable.

Method for producing ruthenium carbene complex The ruthenium carbene complex of the present invention is obtained by treating a ruthenium complex represented by the above formula (2) with an imidazole carbene represented by the above formula (3) and subjecting the phosphine to an imidazole carbene exchange reaction. Can be manufactured by

In the ruthenium complex represented by the formula 2,
R ′ independently represents a hydrocarbon group having 1 to 12 carbon atoms. The hydrocarbon group is usually selected from an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, and an aryl group having 6 to 12 carbon atoms.
A 12 cycloalkyl group and an aryl group having 6 to 12 carbon atoms are preferred. The phosphine PR ′ ₃ in the formula is not particularly limited as long as it can undergo an exchange reaction with imidazole carbene. Specific examples of preferred phosphine PR ′ ₃ include triphenylphosphine, triisopropylphosphine, tributylphosphine, and tricyclopentylphosphine. And tricyclohexylphosphine. Among them, triphenylphosphine is most preferable.

In the imidazole carbene represented by the formula (3), R is the same as R in the above formula (1). The reaction temperature is
Any temperature may be used as long as the generated tri (imidazolecarbene) -coordinated ruthenium complex is stable, and preferably 60 ° C or lower. The temperature is substantially −78 ° C. or more and 60 ° C. or less, and preferably −78 ° C. or more and 30 ° C. or less, which can be reached by dry ice / methanol or the like. The reaction time is not particularly limited, but the substitution reaction between the carbene and the phosphine is very fast, and within 5 hours is sufficient from the viewpoint of productivity. Substantially 0.5 to 5 hours is recommended.

The reaction solvent may be any solvent which dissolves imidazole carbene and the resulting tri (imidazole carbene) -coordinated ruthenium complex and does not react with the trisubstituted ruthenium dichloride, and is not particularly limited. , Ketones, esters, halogenated hydrocarbons, aromatic hydrocarbons and the like. Examples of ethers include diethyl ether, diisopropyl ether, THF, and dioxane, and examples of ketones include acetone, methyl ethyl ketone,
Examples of esters include ethyl acetate, propyl acetate, and butyl acetate; examples of halogenated hydrocarbons include dichloromethane, chloroform, carbon tetrachloride, and chlorobenzene; and examples of aromatic hydrocarbons include benzene, toluene, and xylene. Can be used. Among them, ethers and aromatic hydrocarbons are preferred.

The molar ratio of the imidazole carbene (formula 3) to the starting ruthenium compound (formula 2) may be at least equimolar to the number of phosphine groups in the ruthenium compound (formula 2), and a large excess of imidazole carbene is used. Can be. Further, even if the number of phosphine groups is less than the equimolar number, the desired product is formed, but it is not practical because it becomes a mixture with a disubstituted product and the purification becomes complicated. Further, since it is not economically practical to use a large excess, it is preferable that the substantial amount of imidazole carbene used in the reaction is 3 to 6 equivalents to ruthenium.

According to the above production method, for example, tristriphenylphosphine ruthenium dichloride (PPh ₃ ) ₃
A ruthenium carbene complex represented by Formula 1 can be prepared from RuCl ₂ and imidazole carbene in one step. Compared with the method for producing the ruthenium carbene complex represented by the above formula 4 (Grubbs catalyst) and the ruthenium carbene complex represented by the above formula 5 (Herrmann catalyst) prepared by a multi-step process and using an unstable reaction reagent, The method for producing the ruthenium carbene complex of the present invention represented by the formula 1 is simple and extremely industrially advantageous. The imidazole carbene is synthesized by dehydrating and condensing an organic amine NR ₃ (R is as described above) with paraformaldehyde and glyoxal in the presence of hydrochloric acid to obtain imidazole hydrochloride, followed by hydrogenation in the presence of liquid ammonia. There can be mentioned a method of converting to carbene with sodium,
The method is not particularly limited as long as imidazole carbene can be synthesized.

Method for Producing Cyclic Olefin Polymer The ruthenium carbene complex of the present invention is useful as a polymerization catalyst for metathesis-polymerizing a cyclic olefin. As the cyclic olefin to be polymerized, (1) polycyclic cyclic olefins having a norbornene ring such as norbornenes, dicyclopentadienes, and tetracyclododecenes, and (2) monocyclic cyclic olefins are used. can do. These cyclic olefins may have a substituent such as an alkyl group, an alkenyl group or an alkylidene group, may have a polar group, and may have a double bond other than a double bond of a norbornene ring. It may also have.

Among these cyclic olefins, in order to obtain a ring-opened polymer having excellent heat resistance and solubility, it is preferable to use tricyclic to hexacyclic cyclic olefins having a norbornene ring. Among them, tricyclic cyclic olefins such as dicyclopentadiene and tetracyclic cyclic olefins such as tetracyclododecene are more preferable. Tricyclic cyclic olefins such as dicyclopentadiene are particularly preferred. Specific examples of dicyclopentadienes, that is, tricyclic cyclic olefins having a norbornene ring include dicyclopentadiene and methyldicyclopentadiene, and include a double bond in the 5-membered ring portion of dicyclopentadiene. Saturated tricyclo [4.3.1 ^2,5 . 0] -dec-3-ene and the like. Tetracyclododecenes have the following formula 6
Are included.

[0028]

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(Wherein R _{5 to} R ₁₂ are hydrogen, and have 1 to 3 carbon atoms)
R _{13 to} R ₁₆ represent hydrogen, a hydrocarbon group having 1 to 20 carbon atoms or a substituent containing halogen, silicon, oxygen or nitrogen, and R ₁₃ and R ₁₆
May combine with each other to form a ring. Specific examples of the tetracyclododecenes include (a) tetracyclododecene having no double bond other than a norbornene ring,
Substituents for tetracyclododecenes such as 8-methyltetracyclododecene, 8-ethyltetracyclododecene, 8-cyclohexyltetracyclododecene, 8-cyclopentyltetracyclododecene, and the above tetracyclododecenes (B) those having a double bond other than the norbornene ring, such as 8-methylidenetetracyclododecene, 8-ethylidenetetracyclododecene, 8-vinyltetracyclododecene,
Tetracyclododecenes having a double bond outside the ring, such as -propenyltetracyclododecene, 8-cyclohexenyltetracyclododecene, and 8-cyclopentenyltetracyclododecene; and (c) an aromatic ring. (D) Examples of those having a polar group include 8-methoxycarbonyltetracyclododecene, 8-hydroxymethyltetracyclododecene, and 8-carboxytetracyclod. Tetracyclododecenes having an oxygen-containing substituent such as decene, tetracyclododecene-8,9-dicarboxylic acid and anhydrides thereof; 8-cyanotetracyclododecene, tetracyclododecene-8,9-dicarboxylic acid Tetracyclododecenes having a nitrogen-containing substituent such as imide; Tetracyclododecene compounds having halogen-containing substituents such as tetracyclododecene; tetracyclododecene having 8 trimethoxysilyl tetracyclododecene silicon containing substituent such as Sen and the like.

Specific examples of other cyclic olefins having a norbornene ring include bicyclics having one norbornene ring, such as norbornene, 5-methylnorbornene, 5-ethylnorbornene, 5-butylnorbornene, Norbornenes such as -hexylnorbornene, 5-cyclohexylnorbornene and 5-cyclopentylnorbornene, and corresponding oxanorbornenes; norbornenes having an extracyclic double bond such as 5-ethylidene norbornene, 5-vinyl norbornene and 5-propenyl norbornene And the corresponding oxanorbornenes.

Examples of one having one norbornene ring and one six-membered ring include hexacycloheptadecene, 12-methylhexacycloheptadecene, 12-hexylhexacycloheptadecene, 12-cyclohexylhexacycloheptadecene, and 12-cyclopentyl. Hexacycloheptadecenes such as hexacycloheptadecene, 12-ethylidenehexacycloheptadecene, 12-vinylhexacycloheptadecene, 12-cyclohexenylhexacycloheptadecene, and 12-cyclopentenylhexacycloheptadecene. Examples of those having a norbornene ring and an aromatic ring include 5-phenylnorbornene, 5-phenyloxanorbornene, 1,4-methano-1,4,4a, 9a-tetrahydrofluorene,
1,4-methano-1,4,4a, 5,10,10a-hexahydroanthracene and the like.

Examples of those having a polar group include 5-methoxycarbonylnorbornene, norbornenyl-2-methylpropionate, norbornene-5,6-dicarboxylic anhydride, 5-hydroxymethylnorbornene,
Norbornenes having an oxygen-containing polar group such as-or 5,6-di (hydroxymethyl) norbornene, 5,6-dicarboxynorbornene, 5-methoxycarbonyl-6-carboxynorbornene; 5-methoxycarbonyloxanorbornene, Methyl-5-methoxycarbonyloxanorbornene, oxanorbornenyl-
2-methylpropionate, oxanorbornene-5
6-dicarboxylic anhydride, 5-hydroxymethyloxanorbornene, 5,5- or 5,6-di (hydroxymethyl) oxanorbornene, 5-hydroxy-6-propyloxanorbornene, 5,6-dicarboxyoxanorbornene and the like Oxanorbornenes having an oxygen-containing polar group: norbornenes having a nitrogen-containing polar group such as 5-cyanonorbornene and norbornene-5,6-dicarboxylic imide; 5-cyanooxanorbornene, oxanorbornene-5,6-dicarboxylic acid Oxanorbornenes having a nitrogen-containing polar group such as acid imide are exemplified.

Among the other cyclic olefins having a norbornene ring, from the viewpoints of heat resistance and solubility,
Those having a norbornene ring and an aromatic ring are preferable, and may be copolymerized with the above-mentioned cyclopentadiene, tetracyclododecene or the like. The monocyclic olefins or diolefins have 4 to 20 carbon atoms, and preferably 4 to 20 carbon atoms.
10 cyclic olefins or diolefins and their derivatives. Specific examples thereof include JP-A-64-6621 such as cyclobutene, cyclopentene, methylcyclopentene, cyclohexene and cyclooctene.
6, monocyclic cycloolefin monomers; cyclohexadiene, methylcyclohexadiene,
Examples thereof include cyclic olefin monomers such as cyclooctadiene and phenylcyclooctadiene described in JP-A-7-258318.

The above-mentioned cyclic olefins can be used alone or in combination of two or more. It is also preferable to copolymerize dicyclopentadienes or tetracyclododecenes with a cyclic olefin copolymerizable therewith. In this case, it is preferable to use 10% by weight or more of dicyclopentadiene or tetracyclododecene based on the total monomer polymerization. The ratio of the polymerization catalyst of the present invention to the cyclic olefin is usually from 1: 100 to 1: 2,000,000 (mol / mol) as (metal ruthenium in the polymerization catalyst: cyclic olefin).
Preferably 1: 500 to 1,000,000 (mol / mol), more preferably 1: 1,000 to 1: 500,0.
00 (mol / mol). If the amount of the catalyst is too large, it becomes difficult to remove the catalyst from the polymer, and if the amount is too small, sufficient polymerization activity cannot be obtained. The polymerization reaction can be performed in the presence or absence of a solvent. However, since the cyclic olefin polymer obtained by polymerization using the catalyst of the present invention is soluble in a solvent, a polymerization reaction using a solvent can be advantageously performed.

The polymerization solvent is not particularly limited, and is selected from aliphatic hydrocarbons, aromatic hydrocarbons, heteroatom-containing hydrocarbons and the like. Aliphatic hydrocarbons include butane, pentane, cyclopentane, hexane,
Examples thereof include cyclohexane, methylcyclohexane, octane, and cyclooctane. Examples of the aromatic hydrocarbon include benzene, toluene, xylenes, cumene, and naphthalene. Examples of the hetero atom-containing hydrocarbon include ether compounds such as diethyl ether, dipropyl ether, and tetrahydrofuran (THF), acetone, methyl ethyl ketone, and methyl isobutyl ketone (M
Examples include ketone compounds such as IBK), cyclopentanone and cyclohexanone, esters such as ethyl acetate and butyl acetate, and halogen compounds such as methylene chloride, chloroform, carbon tetrachloride, and chlorobenzene. From the viewpoint of toxicity, hexane, cyclohexane, methylcyclohexane, octane, toluene, and xylenes are preferred.

The reaction temperature may be any temperature which is generally used in industry for the polymerization of cyclic olefins.
A range of from 0C to 200C is recommended. More preferably 20
C. to 150C. Since the ruthenium carbene complex catalyst of the present invention exhibits high catalytic activity even at low temperatures,
Polymerization can be advantageously performed even in a low temperature range of -60 ° C. The reaction time may be within the range usually used industrially,
For example, 30 minutes to 24 hours are recommended. Preferably 1
The time is from 12 hours to 12 hours.

As described above, a polymer obtained by subjecting a cyclic olefin to metathesis polymerization using the ruthenium carbene complex of the present invention as a polymerization catalyst has a high cis content of 30% or more, and cyclohexane, methylcyclohexane, It is soluble in various organic solvents of medium to low polarity such as octane, toluene, xylene, tetrahydrofuran (THF), methylene chloride, chloroform, carbon tetrachloride, chlorobenzene and the like. Therefore, when polymerization is performed using an organic solvent, the polymer is not insolubilized during the polymerization and does not precipitate. Here, the “cis content” indicates the ratio of the cis structure of the main chain double bond of the metathesis polymer. The cis structure when norbornadiene undergoes ring-opening metathesis polymerization is shown in Formula 7 below. The method for measuring the “cis content” is well known in the art and can be measured by any method. Infrared spectroscopy, ¹³ C-NMR analysis, ¹ H-NMR analysis and the like are recommended.

[0038]

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Hereinafter, a synthesis example of the ruthenium carbene complex of the present invention and an application example as a polymerization catalyst will be specifically described. In the following specific examples, the compounds to be synthesized were identified by ¹ H-NMR analysis, and the obtained chemical shifts were shown.

[0040]

EXAMPLE 1 Synthesis of tris (N, N'-dicyclohexylimidazoleylidene) ruthenium dichloride complex Paraformaldehyde (0.15 mol, 4.5 gr) was suspended in toluene (25 ml), and the temperature was 30-40. Cyclohexylamine (0.3 mol, 2
9.8 gr) was added dropwise over 40 minutes. After the addition, the mixture was further stirred for 10 minutes. Cool to 20 ° C, 6N-
Hydrochloric acid (25 ml, 0.15 mol) was added over 30 minutes. To this, 40% -glyoxal (21.8 g
r, 0.15 mol) in 10 minutes. After stirring for 1 hour (the solution is pale yellow), 25 ml of toluene was added. Water was removed by azeotropic distillation (the solution was reddish brown). The solvent was removed from the reaction solution with an evaporator to obtain a reddish brown viscous liquid N, N'-dicyclohexylimymidazolium chloride (Cy salt). [CH ^* -N: δ = 4.25 ppm, CH ^* = CH: δ
= 7.55 ppm, CH ^* = N: δ = 8.8 ppm] Cy salt (1.34 gr, 5 mmol) was added to anhydrous THF (2
0 ml), and sodium hydride (180 m
g, 7.5 mmol). This was cooled to −60 ° C., and ammonia (50 ml) was introduced into the reaction system in about 10 minutes. The reaction temperature was kept at -40 ° C and the mixture was stirred for 2 hours. The Cy salt disappeared with the progress of the reaction. After the reaction, the system was returned to room temperature to remove ammonia. The reaction was filtered under reduced pressure using celite and washed with toluene. TH
F was removed. Toluene was added to this to make the total amount 40
A carbene solution of 0.125 mmol / ml was prepared in accordance with the amount of the carbene.

Tristriphenylphosphine dichlororuthenium (0.5 mmol) was dissolved in 15 ml of toluene. The carbene solution (0.125 mmol
/ Ml, 1.6 mmol) was added dropwise over 10 minutes. After reacting at room temperature for 45 minutes, the solvent was removed with an evaporator. The residue was dissolved in 1 ml of methylene chloride and pentane 20
Precipitated as a solid in ml. This was collected by filtration under reduced pressure. This operation was repeated twice to obtain the desired product. [CH ₃ CH ₂ ^* -: δ = 4.4 ppm, CH ^* = CH: δ
= 10.0 ppm]

Example 2 Synthesis of tris (N, N'-diethylimidazoleylidene) ruthenium dichloride complex Paraformaldehyde (0.15 mol, 4.5 gr) was suspended in toluene (25 ml), and the temperature was 5 to 7 ° C. While maintaining the ethylamine (70% aqueous solution, 0.3 mol,
1.93 gr) was added dropwise over 50 minutes. After completion of the dropwise addition, the mixture was further stirred for 5 minutes. At 10 ° C., 6N hydrochloric acid (25 ml, 0.15 mol) was added over 20 minutes. Heat to 15 ° C. and add 40% -glyoxal (21.
(8 gr, 0.15 mol) in 10 minutes. This one
After stirring for an hour (the solution is pale yellow), 25 ml of toluene was added. Water was removed by azeotropic distillation (the solution was reddish brown). The solvent was removed from the reaction solution using an evaporator, and N, N'-diethylimidazolium chloride (Et.
Salt). [CH ₃ ^* CH ₂ −: δ = 1.5 ppm, CH ₃ ^* CH ₂ −:
δ = 4.25 ppm, CH ^* = CH: δ = 7.5 pp
m, CH ^* = N: δ = 8.8 ppm] Et salt (0.94 gr, 5 mmol) was added to anhydrous THF (2
0 ml), and sodium hydride (180 m
g, 7.5 mmol). This was cooled to −60 ° C., and ammonia (50 ml) was introduced into the reaction system in about 10 minutes. The reaction temperature was kept at -40 ° C and the mixture was stirred for 2 hours. The Et salt disappeared with the progress of the reaction. After the reaction, the system was returned to room temperature to remove ammonia. The reaction was filtered under reduced pressure using celite and washed with toluene. The filtrate was evaporated to remove THF. Toluene was further added thereto to adjust the total amount to 40 ml to prepare a 0.125 mmol / ml carbene solution. Tristriphenylphosphine dichlororuthenium (0.5 mmol)
Dissolved in ml. This was added to the carbene solution (0.12
5 mmol / ml, 1.6 mmol) was added dropwise over 10 minutes. After reacting at room temperature for 45 minutes, the solvent was removed with an evaporator. The residue was dissolved in 1 ml of methylene chloride and precipitated as a solid with 20 ml of pentane. This was collected by filtration under reduced pressure. This operation was repeated twice to obtain the desired product. [CH ₃ ^* CH _2- : δ = 1.5 ppm, CH ₃ CH ₂ ^* -:
δ = 4.4 ppm, CH ^* = CH: δ = 10.0 pp
m]

Comparative Example 1 Synthesis of bis (N, N'-dicyclohexylimidazoleylidene) ruthenium dichloride complex Paraformaldehyde (0.15 mol, 4.5 gr) was suspended in toluene (25 ml), and the temperature was 30 to 40 ° C. While maintaining the cyclohexylamine (0.3 mol, 2
9.8 gr) was added dropwise over 40 minutes. After the addition, the mixture was further stirred for 10 minutes. Cool to 20 ° C, 6N-
Hydrochloric acid (25 ml, 0.15 mol) was added over 30 minutes. To this, 40% -glyoxal (21.8 g
r, 0.15 mol) in 10 minutes. After stirring for 1 hour (the solution is pale yellow), 25 ml of toluene was added. Water was removed by azeotropic distillation (the solution was reddish brown). The solvent was removed by an evaporator to obtain a reddish brown viscous liquid N, N'-dicyclohexylimidazolium chloride (Cy salt). [CH ₂ ^* : δ = 1.2-2.2 ppm, CH ^* -N: δ
= 4.25 ppm, CH ^* = CH: δ = 7.55 pp
m, CH ^* = N: δ = 8.8 ppm] Cy salt (1.34 gr, 5 mmol) was added to anhydrous THF (2
0 ml), and sodium hydride (180 m
g, 7.5 mmol). This was cooled to −60 ° C., and ammonia (50 ml) was introduced into the reaction system in about 10 minutes. The reaction temperature was kept at -40 ° C and the mixture was stirred for 2 hours. The Cy salt disappeared with the progress of the reaction. After the reaction, the system was returned to room temperature to remove ammonia. The reaction was filtered under reduced pressure using celite and washed with toluene. TH
F was removed. Toluene was added to this to make the total amount 40
A 0.125 mmol / ml carbene solution was prepared according to the volume of the carbene solution. Bistriphenylphosphine benzylidene ruthenium dichloride (1.5 mmol, 1.23
gr) was dissolved in 50 ml of toluene. The carbene solution (3.6 mmol) was added dropwise thereto over 5 minutes. After reacting at room temperature for 45 minutes, the solvent was removed with an evaporator. The residue was dissolved in 1 ml of methylene chloride and pentane 2
It precipitated as a solid at 0 ml. This was collected by filtration under reduced pressure. This operation was repeated twice to obtain the desired product. [CH-CH ₃ ^* : δ = 1.2-2.2 ppm, = CH ^* P
h: δ = 20.5 ppm]

Example 3 and Comparative Example 2 Metathesis polymerization of dicyclopentadiene (DCPD) using a ruthenium complex catalyst A magnetic stirrer was placed in a 30 ml ampoule, and the mixture was stoppered and replaced with nitrogen. There, DCPD (2gr, 15.1mmo)
1), 1-hexene (19.1 mg, 0.23 mmol)
l) and cyclohexane (Ts = 20%) were added.
After heating to a predetermined temperature, the respective toluene solutions of the catalysts prepared in Example 1 and Comparative Example 1 were added to initiate polymerization.
After 2 hours, the mixture was allowed to cool and solidified with isopropanol to obtain a polymer. Analysis of the polymer was performed by gel permeation chromatography (GPC). Table 1 shows the polymerization temperature, yield, and cis content of the polymer.

[0045]

[Table 1]

(Monomer / catalyst = 20,000 (mol)
/ Mol))

[0047]

The novel ruthenium carbene complex of the present invention is useful as a polymerization catalyst for cyclic olefins. Despite having a specific structure in which imidazole carbene is coordinated to three, it exhibits good metathesis polymerization activity for cyclic olefins. Further, since the obtained cyclic olefin polymer has a high cis content in the main chain structure, it has good solubility in an organic solvent and can prevent precipitation of the polymer in the polymerization process. Since the ruthenium carbene complex of the present invention does not require the introduction of benzylidene carbene in the production, it is easier to produce than the carbene complexes represented by the formulas 4 and 5, and is industrially advantageous.

Claims (4)

[Claims] 1. A ruthenium carbene complex represented by the following formula 1. Embedded image In the formula 1, R is independently of each other hydrogen or a group having 1 to 1 carbon atoms.
2 represents a hydrocarbon group, which may be substituted with a halogen atom. 2. The ruthenium carbene complex according to claim 1, wherein the ruthenium complex represented by the following formula 2 is treated with an imidazole carbene represented by the following formula 3, and the phosphine and the imidazole carbene are subjected to an exchange reaction. How to manufacture. Embedded image In Formula 2, R ′ independently represents a hydrocarbon group having 1 to 12 carbon atoms. Embedded image In Formula 3, R is independently of each other hydrogen or a group having 1 to 1 carbon atoms.
2 represents a hydrocarbon group, which may be substituted with a halogen atom. 3. A polymerization catalyst comprising the ruthenium carbene complex according to claim 1. 4. A method for producing a polymer, comprising subjecting a cyclic olefin to metathesis polymerization in the presence of the catalyst according to claim 3.