JP2015110581A - Alkylcyclopentadiene compound, and production method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an alkylcyclopentadiene compound the by-product content of which is made lower, which is industrially suitable and can be produced in high yield.SOLUTION: The alkylcyclopentadiene compound has the raw material content and the raw material-derived by-product content which contents are controlled to be 5% or lower, has the objective-derived by-product content which is controlled to be 3% or lower, and is shown by formula (1) (in which R is a 1-4C alkyl group; it does not matter if the 1-4C alkyl group is substituted for optional H on a cyclopentadiene ring). In the production method of the alkylcyclopentadiene compound, it does not matter if one of quaternary onium salt, a base and alkyl halide is mixed and reacted finally, if cyclopentadiene is mixed previously, or if the cyclopentadiene is mixed finally.

Description

  The present invention relates to a method for producing an alkylcyclopentadiene compound. The alkylcyclopentadiene compound is useful as a synthesis precursor for an olefin polymerization catalyst such as a metallocene catalyst, or as a precursor material for chemical vapor deposition (Chemical Vapor Deposition).

  Conventionally, as a method for producing an alkylcyclopentadiene compound, for example, cyclopentadiene and a metal hydroxide are reacted to form a cyclopentadienyl metal, and then this is reacted with an alkyl halide in dimethyl sulfoxide. A method for producing alkylcyclopentadiene (see, for example, Patent Document 1), or after forming cyclopentadienyl sodium from sodium metal and cyclopentadiene, this is reacted with an alkylating agent in an ether solvent to obtain alkylcyclopentadiene. Is disclosed (for example, see Non-Patent Document 2).

JP 2001-97895 A

Tetrahedron, Vol. 21, 313 (1965)

  An object of the present invention is to solve the above-mentioned problems and provide an industrially suitable alkylcyclopentadiene compound having a reduced by-product content in a high yield.

  The subject of the present invention is a general formula (1) in which the content of raw materials and by-products derived only from the raw materials is 5% or less, and the content of by-products derived from the target product is 3% or less.

(In the formula, R represents an alkyl group having 1 to 4 carbon atoms. Any hydrogen atom on the cyclopentadiene ring may be substituted with an alkyl group having 1 to 4 carbon atoms.)
It is solved by an alkylcyclopentadiene compound represented by:

  According to the present invention, an alkylcyclopentadiene compound useful as a synthesis precursor of an olefin polymerization catalyst such as a metallocene catalyst or as a precursor material for chemical vapor deposition is reduced by-products, and A high yield can be provided.

(Alkylcyclopentadiene compound)
In the alkylcyclopentadiene compound of the present invention, the content of the by-product derived from only the raw material and the raw material is 5% or less, and the content of the by-product derived from the target product is 3% or less. In the general formula (1), R represents an alkyl group having 1 to 4 carbon atoms, for example, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a t-butyl group. And preferably a methyl group or an ethyl group. Note that any hydrogen atom on the cyclopentadiene ring may be substituted with an alkyl group having 1 to 4 carbon atoms.

  Examples of the alkylcyclopentadiene as the alkylcyclopentadiene compound of the present invention (any hydrogen atom on the cyclopentadiene ring may be substituted with an alkyl group having 1 to 4 carbon atoms) include, for example, methylcyclopentadiene, ethyl Monoalkylcyclopentadiene such as cyclopentadiene, n-propylcyclopentadiene, isopropylcyclopentadiene, n-butylcyclopentadiene, t-butylcyclopentadiene, sec-butylcyclopentadiene; dimethylcyclopentadiene, methylethylcyclopentadiene, diethylcyclopentadiene, Di-n-propylcyclopentadiene, diisopropylcyclopentadiene, di-n-butylcyclopentadiene, disec-butylcyclopentadiene, di-t-butyl Dialkylcyclopentadiene such as clopentadiene; trialkylcyclopentadiene such as trimethylcyclopentadiene, dimethyl (ethyl) cyclopentadiene, diethyl (methyl) cyclopentadiene, tri-t-butylcyclopentadiene; tetraalkylcyclopentadiene such as tetramethylcyclopentadiene; Examples include pentaalkylcyclopentadiene such as pentamethylcyclopentadiene. These alkylcyclopentadiene compounds include various positional isomers.

  For example, in the production of a monoalkylcyclopentadiene using cyclopentadiene as a raw material, a by-product derived from only the raw material is a compound that generates only the raw material when pyrolyzed (cracked). Pentadiene. On the other hand, as a by-product derived from the product, it is a compound that generates a raw material and a product when pyrolyzed (cracking) (at least a product is generated). For example, cyclopentadiene and monoalkylcyclopentadiene And a multimer of monoalkylcyclopentadiene such as dialkyldicyclopentadiene.

  In the alkylcyclopentadiene compound of the present invention, the content of the by-product derived from only the raw material and the raw material is 5% or less, and the content of the by-product derived from the target product is 3% or less. When the content of the raw material and the by-product derived from the raw material is more than 5%, for example, when producing an alkylcyclopentadienyl metal complex, the metal complex derived from the raw material is mixed as a by-product, which is undesirable. When the amount of by-products derived from the product is more than 3%, the yield of the target alkylcyclopentadienyl metal complex is lowered.

(Method for producing alkylcyclopentadiene compound)
The alkylcyclopentadiene compound of the present invention is prepared by mixing a quaternary onium salt, a base, an alkyl halide and cyclopentadiene to produce an alkylcyclopentadiene. In the present invention, any of the quaternary onium salt, the base and the alkyl halide It is performed by the method of mixing and reacting one last. Cyclopentadiene may be mixed in advance (the following (1) to (3)) or finally mixed (the following (4) to (6)). In addition, as for the cyclopentadiene as a raw material at this time, the arbitrary hydrogen atom on a cyclopentadiene ring may be substituted by the C1-C4 alkyl group.

That is, it is performed by one of the following methods.
Method (1): After mixing cyclopentadiene, quaternary onium salt and base, an alkyl halide is added and reacted.
Method (2): After mixing cyclopentadiene, quaternary onium salt and alkyl halide, a base is added and reacted.
Method (3): After mixing cyclopentadiene, base and alkyl halide, a quaternary onium salt is added and reacted.
Method (4): After mixing a quaternary onium salt and a base, cyclopentadiene and an alkyl halide are added and reacted.
Method (5): After mixing a quaternary onium salt and an alkyl halide, cyclopentadiene and a base are added and reacted.
Method (6): After mixing a base and an alkyl halide, cyclopentadiene and a quaternary onium salt are added and reacted.

  The cyclopentadiene used in the reaction of the present invention can be obtained, for example, by cracking a cyclopentadiene dimer at 150 to 200 ° C., and can be used as it is.

  The quaternary onium salt used in the reaction of the present invention is, for example, tetrabutylammonium bromide, tetrabutylammonium chloride, tetrapropylammonium bromide, tetraethylammonium bromide, tetramethylammonium bromide, tetradecylammonium bromide, hexyltrimethylammonium bromide. Tetraalkyl such as hexyldimethyloctylammonium bromide, trimethyl-n-octylammonium bromide, tetraamylammonium chloride, dodecyltrimethylammonium chloride, dodecyltrimethylammonium bromide, decyltrimethylammonium chloride, didecyldimethylammonium bromide, lauryltrimethylammonium bromide Ammonium salt; benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, benzyltriethylammonium chloride, benzyltriethylammonium bromide, benzyltributylammonium chloride, benzyltributylammonium bromide, benzyldimethyltetradecylammonium chloride, benzyldimethylstearylammonium chloride, benzylcetyldimethylammonium Aralkyl trialkylammonium salts such as chloride; 2-hydroxypropyltrimethylammonium chloride, 2-hydroxyethyltrimethylammonium chloride, 2-hydroxyethyltrimethylammonium bromide, tris (2-hydroxyethyl) methylammoni Mukuroraido, tris (2-hydroxyethyl) including but tetraalkyl ammonium salts substituted by a hydroxy group, such as methyl bromide, preferably tetrabutylammonium bromide, tetrabutylammonium chloride is used.

  The amount of the quaternary onium salt to be used is preferably 0.0001 to 50 mol, more preferably 0.001 to 5 mol, per 1 mol of cyclopentadiene.

  Examples of the alkyl halide used in the reaction of the present invention include alkyl chloride, alkyl bromide, and alkyl iodide, preferably alkyl chloride, alkyl bromide, and more preferably alkyl bromide. Even if the halogens are different, as long as the alkyl groups are the same, two or more alkyl halides may be used in combination.

  The amount of the alkyl halide to be used is preferably 0.1 to 10 mol, more preferably 0.5 to 6 mol, per 1 mol of cyclopentadiene.

  Examples of the base used in the reaction of the present invention include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium hydroxide, strontium hydroxide, preferably sodium hydroxide, water Potassium oxide, more preferably sodium hydroxide is used. In addition, you may use these bases individually or in mixture of 2 or more types.

  The amount of the base used is preferably 0.1 to 20 mol, more preferably 0.5 to 5 mol, per 1 mol of cyclopentadiene.

  In the reaction of the present invention, for example, when an alkylcyclopentadiene is produced by mixing a quaternary onium salt, a base, an alkyl halide and cyclopentadiene, any one of the quaternary onium salt, the base or the alkyl halide is finally mixed. The reaction temperature at that time is preferably 0 to 150 ° C., more preferably 10 to 60 ° C., and the reaction pressure is not particularly limited.

  Although the reaction mixture containing the alkylcyclopentadiene compound is obtained by the reaction of the present invention, for example, the alkylcyclopentadiene compound can be obtained by neutralizing, extracting, separating, concentrating, filtering, etc. the reaction mixture.

  In the present invention, the alkylcyclopentadiene compound obtained by the above method was further distilled at 25 to 150 ° C., and then the low boiling point component was distilled off, followed by heat treatment at 150 to 250 ° C., thereby further reducing impurities. A highly pure alkylcyclopentadiene compound can be obtained.

  By heat-treating at 25 to 150 ° C., the unreacted raw material (low boiling point component) can be distilled off from the alkylcyclopentadiene compound.

  Subsequently, by heat treatment at 150 to 250 ° C., by-products derived only from the raw material and by-products derived from the target product are pyrolyzed (cracked) to obtain the raw material and the target product (alkylcyclopentadiene). While distilling off a certain raw material, the target alkylcyclopentadiene compound can be obtained.

  By the above operation, a higher purity alkylcyclopentadiene compound is obtained in which the content of by-products derived from the raw material or the raw material alone is 5% or less and the content of by-products derived from the target product is 3% or less. Can do.

Next, the present invention will be specifically described with reference to examples, but the scope of the present invention is not limited thereto. The target product and by-products were analyzed under the following conditions.
(Conditions for gas chromatography analysis)
Analyzer; SHIMAZU GC-2014
Analytical column; G250

Example 1 (R = ethyl group; synthesis of ethylcyclopentadiene (method (4))
6 mL (48 mmol) of 8 mol / l sodium hydroxide aqueous solution and 0.118 g (0.365 mmol) of tetrabutylammonium bromide were added to a 100-ml flask equipped with a dropping funnel and a thermometer, and stirred at room temperature. Subsequently, a mixed solution of 2.7 ml (36.5 mmol) of ethyl bromide and 3.5 ml (43 mmol) of cyclopentadiene was dropped, and the mixture was reacted for 6 hours while stirring. After completion of the reaction, the reaction solution was separated, the organic layer was separated, and the resulting organic layer was washed with water. When the obtained organic layer was analyzed by gas chromatography, the production rate of ethylcyclopentadiene was 79.7%.

Example 2 (R = ethyl group; synthesis of ethylcyclopentadiene (method (2))
Tetrabutylammonium bromide 0.118 g (0.365 mmol), ethyl bromide 2.7 ml (36.5 mmol) and cyclopentadiene 3.5 ml (43 mmol) were added to a 100 ml internal volume flask equipped with a dropping funnel and a thermometer. Stir at room temperature. Next, 6 ml (48 mmol) of an 8 mol / l aqueous sodium hydroxide solution was added dropwise and reacted for 6 hours with stirring. After completion of the reaction, the reaction solution was separated, the organic layer was separated, and the resulting organic layer was washed with water. When the obtained organic layer was analyzed by gas chromatography, the production rate of ethylcyclopentadiene was 82.6%.

Example 3 (R = ethyl group; synthesis of ethylcyclopentadiene (method (1))
To a 100 ml flask equipped with a dropping funnel and a thermometer, 8 ml / l aqueous sodium hydroxide solution 6 ml (48 mmol), tetrabutylammonium bromide 0.118 g (0.365 mmol) and cyclopentadiene 3.5 ml (43 mmol) were added. And stirred at room temperature. Next, 2.7 ml (36.5 mmol) of ethyl bromide was added dropwise and reacted for 6 hours with stirring. After completion of the reaction, the reaction solution was separated, the organic layer was separated, and the resulting organic layer was washed with water. When the obtained organic layer was analyzed by gas chromatography, the yield of ethylcyclopentadiene was 82.0%.

Comparative Example 1 (R = ethyl group; synthesis of ethylcyclopentadiene)
Into a 100 ml flask equipped with a dropping funnel and a thermometer, 6 ml (48 mmol) of 8 mol / l sodium hydroxide aqueous solution, 0.118 g (0.365 mmol) of tetrabutylammonium bromide and 2.7 ml (36.5 mmol) of ethyl bromide And stirred at room temperature. Next, 3.5 ml (43 mmol) of cyclopentadiene was added dropwise and reacted for 6 hours with stirring. After completion of the reaction, the reaction solution was separated, the organic layer was separated, and the resulting organic layer was washed with water. When the obtained organic layer was analyzed by gas chromatography, the production rate of ethylcyclopentadiene was 65.9%.

Example 4 (R = ethyl group; synthesis of ethylcyclopentadiene (method (4))
30 ml (240 mmol) of 8 mol / l sodium hydroxide aqueous solution and 0.59 g (1.82 mmol) of tetrabutylammonium bromide were added to a 200 ml internal flask equipped with a dropping funnel and a thermometer and stirred at room temperature. Subsequently, a mixed solution of 13.5 ml (182.5 mmol) of ethyl bromide and 17.5 ml (215 mmol) of cyclopentadiene was added dropwise and reacted for 6 hours while stirring. After completion of the reaction, the reaction solution was separated, the organic layer was separated, and the resulting organic layer was washed with water.
After adding the organic layer to a vessel equipped with a distillation apparatus and distilling off a low-boiling component (main component is cyclopentadiene) at 120 to 150 ° C., heat treatment is then performed at 200 to 220 ° C. to obtain dicyclopentadiene, Diethyldicyclopentadiene, and a complex of cyclopentadiene and ethylcyclopentadiene were pyrolyzed (cracked), and then low-boiling components (main component was cyclopentadiene) were distilled off.
Thereafter, 5.72 g of ethylcyclopentadiene was obtained at 220 to 240 ° C. (isolation yield; 37.8%). The obtained ethylcyclopentadiene (fraction) was analyzed by gas chromatography.
As a result, the content of by-products in ethylcyclopentadiene was as follows.

(By-products derived from raw materials or raw materials only)
Cyclopentadiene; 0.8%
Dicyclopentadiene; less than 0.1% (by-product derived from the target product)
Complex of cyclopentadiene and ethylcyclopentadiene; 0.1%
Diethyldicyclopentadiene; 0.5%
Triethyltricyclopentadiene; less than 0.1%

  As distillation residues, 2.11 g (12.3% based on ethyl bromide) were present as high-boiling components such as dicyclopentadiene, a complex of cyclopentadiene and ethylcyclopentadiene, and diethyldicyclopentadiene.

  Furthermore, the content of cyclopentadiene was less than 0.1% by subjecting the ethylcyclopentadiene to a reduced pressure treatment (2 to 3 kPa) at room temperature.

Comparative Example 2 (R = ethyl group; synthesis of ethylcyclopentadiene)
Into a 200-ml flask equipped with a dropping funnel and a thermometer, 30 ml (240 mmol) of 8 mol / l aqueous sodium hydroxide, 0.59 g (1.82 mmol) of tetrabutylammonium bromide and 13.5 ml (182.5 mmol) of ethyl bromide And stirred at room temperature. Next, a mixed solution of 17.5 ml (215 mmol) of cyclopentadiene was added dropwise and reacted for 6 hours with stirring. After completion of the reaction, the reaction solution was separated, the organic layer was separated, and the resulting organic layer was washed with water.
The organic layer is added to a container equipped with a vacuum distillation apparatus, and low-boiling components are distilled off at 25 ° C. under reduced pressure (2.7 to 13.3 kPa). 2.67 kPa) and 4.85 g of ethylcyclopentadiene were obtained at 25 ° C. (isolation yield: 28.3%). The obtained ethylcyclopentadiene (fraction) was analyzed by gas chromatography.
As a result, the content of by-products in ethylcyclopentadiene was as follows.

(By-products derived from raw materials or raw materials only)
Cyclopentadiene; 1.03%
Dicyclopentadiene; 0.76%
(By-product derived from the target)
Complex of cyclopentadiene and ethylcyclopentadiene; 0.5%
Diethyldicyclopentadiene; 1.4%
Triethyltricyclopentadiene; less than 0.1%

  As distillation residues, 2.52 g (14.7% based on ethyl bromide) of high-boiling components such as dicyclopentadiene, a complex of cyclopentadiene and ethylcyclopentadiene, and diethyldicyclopentadiene were present.

Example 5 (R = ethyl group; synthesis of ethylmethylcyclopentadiene mixture (method (4)) Into a 100 ml flask equipped with a dropping funnel and a thermometer, 26 ml (207 mmol) of an 8 mol / l aqueous sodium hydroxide solution and tetra 0.51 g (1.58 mmol) of butylammonium bromide was added and stirred at room temperature, and then a mixture of 11.7 ml (157.5 mmol) of ethyl bromide and 14.91 g (186 mmol) of methylcyclopentadiene was added dropwise and stirred. The reaction was allowed to proceed for 10 hours at 50 ° C. After completion of the reaction, the reaction solution was separated, the organic layer was separated, and the resulting organic layer was washed with water.
After adding the organic layer to a vessel equipped with a distillation apparatus to distill off low-boiling components (main component is methylcyclopentadiene) at 120 to 220 ° C., heat treatment is then carried out at 220 to 230 ° C. to dimethyldicyclohexane. After thermal decomposition (cracking) of the complex of pentadiene, diethyldicyclopentadiene, methylcyclopentadiene and ethylcyclopentadiene, the low boiling point component (main component is methylcyclopentadiene) was distilled off.
Thereafter, 2.89 g of ethylmethylcyclopentadiene was obtained at 230 to 240 ° C. (isolation yield; 17.0%). The obtained ethylmethylcyclopentadiene (fraction) was analyzed by gas chromatography.
As a result, the content of by-products in ethylmethylcyclopentadiene was as follows.

(By-products derived from raw materials or raw materials only)
Methylcyclopentadiene; 3.9%
Dimethyldicyclopentadiene; 1.0%
(By-product derived from the target)
Complex of methylcyclopentadiene and ethylmethylcyclopentadiene; 0.5%
Diethyldimethyldicyclopentadiene; 0.5%
Triethyltrimethyltricyclopentadiene; 0.5%

  The distillation residue contains 2.71 g (15.9% based on ethyl bromide) of high-boiling components such as dimethyldicyclopentadiene, a complex of methylcyclopentadiene and ethylmethylcyclopentadiene, and diethyldimethyldicyclopentadiene. It was.

  Further, the ethylmethylcyclopentadiene was subjected to a reduced pressure treatment (2.7 to 13.3 kPa) at room temperature, whereby the methylcyclopentadiene content was 0.6%.

  According to the present invention, it is possible to provide an alkylcyclopentadiene compound that is useful as a synthesis precursor of a catalyst for olefin polymerization such as a metallocene catalyst or as a precursor material for chemical vapor deposition.

Claims (4)

The general formula (1), wherein the content of raw materials and by-products derived only from the raw materials is 5% or less, and the content of by-products derived from the target product is 3% or less.
(In the formula, R represents an alkyl group having 1 to 4 carbon atoms. Any hydrogen atom on the cyclopentadiene ring may be substituted with an alkyl group having 1 to 4 carbon atoms.)
An alkylcyclopentadiene compound represented by:   The alkylcyclopentadiene compound according to claim 1, wherein the content of the by-product derived from only the raw material and the raw material is 5% or less and the content of the by-product derived from the target product is 3% or less.   In the method for producing an alkylcyclopentadiene by mixing a quaternary onium salt, a base, an alkyl halide and cyclopentadiene, any one of a quaternary onium salt, a base and an alkyl halide is mixed and reacted at the end. 5. The method for producing an alkylcyclopentadiene compound according to any one of 4 above.   The alkylcyclopentadiene compound obtained by the method according to claim 3 is further heat-treated at 150 to 250 ° C after distilling off low-boiling components at 25 to 200 ° C. Compound production method.