JP2003183203A - Method for producing ethyl group-containing alicyclic tertiary alcohol - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing an ethyl group-containing alicyclic tertiary alcohol, by which good hydrogenation of ethynylated alicyclic tertiary alcohol be attained and the ethyl group-containing alicyclic tertiary alcohol can be obtained in high yield. <P>SOLUTION: This method for producing the ethyl group-containing alicyclic alcohol comprises carrying out (1) a step for producing the ethynylated alicyclic tertiary alcohol by reacting a cyclic ketone with acetylene in the presence of an alkali catalyst in a solvent (A), (2) a step for extracting the resultant ethynylated alicyclic tertiary alcohol with a solvent (B) having high compatibility for the alcohol and low compatibility for the solvent (A) and water and not inhibiting activity of hydrogenation catalyst of the successive hydrogenation step, (3) a step for washing a solvent (B) layer containing the ethynylated alicyclic tertiary alcohol and (4) a step for hydrogenating the ethynylated alicyclic tertiary alcohol in the solvent (B) in this order. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing an ethyl group-containing alicyclic tertiary alcohol.

[0002]

2. Description of the Related Art Ethyl group-containing alicyclic tertiary alcohols are
It is a useful compound as a raw material for photoresists and the like. As a production method thereof, for example, a method of alkylating a specific ketone with a Grignard reagent is known (Japanese Patent Laid-Open No. 2001-213826). This method
Although it is excellent in that the yield of the ethyl group-containing alicyclic tertiary alcohol is high, it has a drawback that magnesium halide in an equimolar amount with respect to the ketones is generated as waste. Further, as a method for producing an ethyl group-containing alicyclic tertiary alcohol, a method via an ethynylated alicyclic tertiary alcohol, that is, a ketone and acetylene are reacted in the presence of an alkali catalyst to produce an ethynylated alicyclic tertiary alcohol. A method of obtaining a group-III tertiary alcohol and hydrogenating it is also conceivable. In this case, as a method for producing the ethynylated alicyclic tertiary alcohol as a raw material, a method using various polar aprotic solvents (for example, N-methylpyrrolidone) as a solvent when reacting a ketone with acetylene is used. Known (Japanese Patent Publication 60-598)
88, J. Org. Chem., Vol. 27, 1498 (1962)).
However, it is known to the present inventors that when the ketones and acetylene are reacted by the above method, if the reaction mixture containing the polar aprotic solvent is directly subjected to the hydrogenation step, the hydrogenation reaction is significantly inhibited. There was a problem.

[0003]

Therefore, an object of the present invention is to provide an ethynylated alicyclic tertiary alcohol (hereinafter sometimes abbreviated as ethynylated alcohol) obtained by reacting a ketone with acetylene. A method for producing an ethyl group-containing alicyclic tertiary alcohol (hereinafter, may be abbreviated as an ethyl group-containing alcohol) via a method for achieving good hydrogenation of an ethynylated alicyclic tertiary alcohol, and finally The object of the present invention is to provide a method for obtaining an ethyl group-containing alicyclic tertiary alcohol, which is a specific object, in high yield.

[0004]

Means for Solving the Problems As a result of intensive research to solve the above problems, the present inventors have found that in the process for producing an ethynylated alcohol for reacting a ketone with acetylene,
After extracting the reaction product with a specific treatment step, that is, a specific solvent (B) different from the solvent (A) used in the reaction,
It was found that by adding a step of further washing with water, good hydrogenation of an ethynylated alcohol was achieved, and an ethyl group-containing alcohol could be produced in a high yield.

Accordingly, the present invention is a method for producing an ethyl group-containing alicyclic tertiary alcohol characterized by carrying out the following steps in the following order: (1) In solvent (A), alkali A step of reacting a cyclic ketone with acetylene in the presence of a catalyst to produce an ethynylated alicyclic tertiary alcohol; (2) converting the obtained ethynylated alicyclic tertiary alcohol to the ethynylated alicyclic tertiary alcohol; A step of extracting with a solvent (B) which has a high compatibility with a trialcohol and a low compatibility with the solvent (A) and water and does not inhibit the activity of the hydrogenation catalyst in the subsequent hydrogenation step, (3) ethinyl The step of washing the solvent (B) layer containing the alicyclic tertiary alcohol with water, (4) the step of hydrogenating the ethynylated alicyclic tertiary alcohol in the solvent (B).

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the first step of the method of the present invention, an ethynylated alcohol is produced by reacting a cyclic ketone with acetylene in a solvent (A) in the presence of an alkali catalyst. The cyclic ketone used here is an alicyclic ketone having at least one ring, that is, in an alicyclic hydrocarbon having one or more rings, one ketone group on any ring. Is a compound having Specifically, cyclopentanone, cyclohexanone, methylcyclohexanone, cycloheptanone, cyclooctanone, menthone, norbornanone, adamantane and the like are preferable, and cyclopentanone, cyclohexanone and adamantane are preferable.

As the solvent (A) used in the reaction, a polar aprotic solvent is usually used. Specifically, amines such as N-methylpyrrole, N-methylpyrrolidine, N-methylmorpholine and pyridine; N , Amides such as N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone and 2-imidazolidinones; nitriles such as acetonitrile and benzonitrile; sulfoxides such as dimethyl sulfoxide and diethyl sulfoxide; tetramethylene Examples thereof include sulfones such as sulfone and diethyl sulfone; and phosphoric acid amides such as hexamethylphosphoric triamide and hexaethylphosphoric triamide. Of these, preferably N, N-dimethylformamide, N, N-dimethylacetamide, N-
Methylpyrrolidone, acetonitrile, dimethylsulfoxide, 2-imidazolidinones, particularly preferably N-methylpyrrolidone, dimethylsulfoxide, 1,3
-Dimethyl-2-imidazolidinone and N, N-dimethylformamide.

The alkali catalyst used in the first step can be selected from alkali metal, alkali metal hydroxide or alkali metal alcoholate. Examples of the alkali metal include sodium metal and potassium, and examples of the alkali metal hydroxide include sodium hydroxide, potassium hydroxide, lithium hydroxide, rubidium hydroxide, and cesium hydroxide. Examples of the alkali metal alcoholate include potassium methylate, potassium ethylate, potassium isobutyrate,
Aliphatic alkali metal alcoholates such as potassium-t-butyrate, sodium methylate and sodium ethylate can be mentioned. Also, alicyclic alkali metal alcoholates such as potassium cyclohexylate can be used. Of these, the alkali metal hydroxides exemplified above are particularly preferable.

These alkali catalysts are used in an amount of 0.05 to 3 moles, preferably 0.1 to 3 moles per 1 mole of the starting ketones.
Used in the proportion of 1 mol. When the amount of the catalyst is less than 0.1 mol based on 1 mol of the ketones, the reaction rate becomes slow and the conversion rate deteriorates. Further, when the amount of the catalyst is 3 mol or more per 1 mol of the ketones, the amount of the alkali catalyst is unnecessarily excessive, which is not economical.

The reaction temperature between the cyclic ketone and acetylene is
The temperature is 0 ° C to 100 ° C, preferably 10 ° C to 80 ° C. The reaction pressure is usually 0 as acetylene partial pressure.
˜1 MPa (gauge pressure), preferably 0 to 0.2 MPa (gauge pressure). The higher the acetylene partial pressure, the higher the reaction rate. However, since acetylene easily causes decomposition and explosion, it is preferable to lower the acetylene partial pressure as much as possible in order to prevent it. Therefore, an inert gas such as nitrogen, argon, or propane may be introduced to dilute the acetylene for the reaction.

The molar ratio of acetylene to cyclic ketone is at least 1 acetylene to 1 mol of cyclic ketone.
There is no particular limitation as long as it is at least a molar amount, and the reaction is generally carried out in a large excess of acetylene.

The reaction time of this reaction depends on the raw material ratio, the reaction temperature,
Depending on other conditions such as acetylene partial pressure, usually 0.5
It is 10 hours, preferably 1 to 6 hours.

After the reaction, water is added to the reaction mixture to stop the ethynylation reaction. At this time, the amount of water added is 1 to 100 mol per 1 mol of the charged cyclic ketone. The added water does not usually need to be separated, and is used as it is in the next step.

In the subsequent second step, the solvent (B) is added to the product mixture and the target product, an ethynylated alcohol, is extracted. The extraction method may be a batch system or a continuous system, but in the case of a batch system, after the extraction system is stirred, the stirring is stopped to separate into two layers. Usually, the upper layer contains the solvent (B)
And most of the ethynylated alcohol extracted by the solvent (B). On the other hand, the lower layer contains the solvent (A) and a small amount of ethynylated alcohol, and also contains the alkali catalyst and water which have been transferred to the lower layer by the extraction treatment. This extraction process is carried out with the product mixture (ethynylated alcohol, solvent (A), water, unreacted raw materials, by-products, alkali catalyst)
The solvent (B) is added in an amount of 20 to 50% by weight based on the amount of, and extracted with stirring. This operation is usually performed once, but if the recovery of the ethynylated alcohol is poor, it is repeated once or twice. By this extraction, generally 70% by weight or more of the ethynylated alicyclic tertiary alcohol can be recovered.

The solvent (B) used in the second step has a high compatibility with the produced ethynyl alcohol, while having a low compatibility with the solvent (A) and water, and does not inhibit the activity of the hydrogenation catalyst. It is a thing. As the solvent (B) satisfying these conditions, ethers, saturated aliphatic hydrocarbons, or aromatic hydrocarbons are preferable. As the ethers, ethers having an alkyl group having 1 to 4 carbon atoms, for example, diethyl ether, dipropyl ether, t
-Butyl methyl ether, isopropyl ether and the like can be mentioned. The saturated aliphatic hydrocarbons have 5 carbon atoms.
To 12 chain saturated aliphatic hydrocarbons such as hexane, heptane, octane, nonane, decane, and alicyclic saturated aliphatic hydrocarbons having 5 to 12 carbon atoms such as cyclohexane and decalin. . Aromatic hydrocarbons include toluene, xylene, ethylbenzene,
Mesitylene etc. are mentioned. Of these, preferred solvent (B) is diethyl ether, dipropyl ether, diisopropyl ether, t-butyl methyl ether, toluene, and hexane.

In the third step, the solvent (B) layer containing the ethynylated alicyclic tertiary alcohol is washed with water. After the extraction treatment in the second step, the obtained solvent (B) layer may still contain the solvent (A) and the catalyst, and if they are contained in a relatively large amount, it may adversely affect the subsequent hydrogenation step. Because it gives. The amount of water used is 10 based on the amount of the solvent (B) layer.
~ 50% by weight. The method of washing with water may be a batch type or a continuous type.
You can do it 3 times. Solvent (A) in solvent (B) layer after washing with water
In general, the residual amount is preferably 5% by weight or less. The residual amount of water in the solvent (B) layer is generally preferably 1% by weight or less.

In the final fourth step, the ethynylated alcohol is hydrogenated in the solvent (B) in the presence of a hydrogenation catalyst to give an ethyl group-containing alcohol. As the hydrogenation catalyst, a metal catalyst such as nickel, palladium, ruthenium, rhodium or platinum is generally used. In addition, these catalysts are generally used by supporting them on an inert carrier. As the inert carrier, for example, carbon, silica, alumina, silica-alumina, magnesia, etc. are preferable, and carbon or alumina is particularly preferable. The metal catalyst is loaded on the carrier by an impregnation method,
It can be carried out by an ordinary method such as a precipitation method. At this time, the amount of metal supported is not particularly limited, but is preferably 0.3 to 10% by weight. Further, a commercially available supported hydrogenation catalyst in the present invention can be used as it is.

The amount of the metal catalyst used in the hydrogenation reaction is not particularly limited, but it is usually in the range of 0.001 to 1% by weight, preferably 0.05 to 0.5% by weight, based on the ethynylated alcohol. %.

As the reaction solvent for the hydrogenation reaction, the solvent (B) described above as the extraction solvent is generally used. It is preferred to use the same solvent used as the extraction solvent. In these reaction solvents, preferably diethyl ether, dipropyl ether, isopropyl ether, t
-Butyl methyl ether, toluene and hexane, particularly preferably t-butyl methyl ether, toluene and isopropyl ether.

The reaction conditions for hydrogenation are not particularly limited, but the reaction temperature is usually 30 to 150 ° C., preferably 40 to
The temperature is 100 ° C., and the hydrogen pressure is 0.3 to 15 MPa, preferably 0.5 to 10 MPa. The reaction time is 1 to 20.
The time is preferably 2 to 10 hours.

From the reaction mixture obtained by the above hydrogenation reaction, the hydrogenation catalyst is first removed by a precipitation method, a filtration method, a centrifugation method or the like, and then the solvent (B) is separated by a distillation method or the like. Ethyl group-containing alcohol can be recovered.

[0022]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.
The raw material ketone and the product were analyzed by gas chromatography. Further,% in the examples is on a weight basis unless otherwise specified.

Example 1 <Ethynylation Step> Into a 1.1 L reactor, 635 g of dimethylformamide as a reaction solvent and 50 g of potassium hydroxide as a catalyst (12 mol% with respect to a ketone raw material) were charged, and 67.9 g of cyclohexanone ( 0.63 mol) and acetylene were fed and reacted. The supply of cyclohexanone, which is a raw material, was carried out over 3 hours from the start of the supply, and the reaction with acetylene was for 4 hours with the start of the supply of cyclohexanone being the reaction start time, and the reaction pressure was 0.
The reaction temperature was 02 MPa and the temperature was 25 ° C. After the reaction, water was added to the reaction mixture in an amount corresponding to 1/3 of the liquid amount (on a weight basis; the same applies below) to stop the reaction.

When the product mixture was analyzed, the conversion of cyclohexanone was 96.3% and the yield of 1-ethynyl-1-cyclohexanol was 86.4 mol%.

<Extraction Step> Next, with respect to 430 g of the liquid of the above reaction mixture containing water, 2/3 of this liquid amount as an extractant was used.
A considerable amount of t-butyl methyl ether was added. After stirring this liquid, it was left to stand and separated into two layers of an organic phase and an aqueous phase. The organic phase was recovered and analyzed to show 1-ethynyl-
The 1-cyclohexanol extraction rate was 84.2%.

<Washing Step> Next, to 300 g of the organic layer thus extracted, 1/3 of the water of the organic layer was added,
Washed with water. That is, the liquid to which water was added was stirred and then separated, and the organic layer was recovered. This operation was repeated twice more. When the obtained organic layer was analyzed, 1-ethynyl-
The recovery rate of 1-cyclohexanol was 80.4%.

<Hydrogenation reaction> Palladium supported on carbon (palladium 0.0
15 g), and the hydrogenation reaction is carried out for 8 times while supplying hydrogen.
I went on time. The reaction conditions are a temperature of 50 ° C and a pressure of 1.0 MPa.
Met. As a result of the analysis, the conversion rate of 1-ethynyl-1-cyclohexanol by the hydrogenation reaction was 99.9%, and the yield of 1-ethyl-1-cyclohexanol was 7%.
It was 2.0%.

Comparative Example 1 In this example, the hydrogenation reaction was carried out without performing extraction with t-butyl methyl ether and washing with water. That is, Example 1
The reaction of cyclohexanol and acetylene was carried out under the same conditions as above to obtain a product mixture. Next, the resulting product mixture was stirred for 4 hours while blowing carbon dioxide gas to neutralize the potassium hydroxide as a catalyst. Use this mixture as is,
When the hydrogenation reaction was carried out under the same conditions as in Example 1, 1-
The conversion of ethynyl-1-cyclohexanol is 70.1.
%, And the yield of 1-ethyl-1-cyclohexanol was 3.9%. Therefore, when the extraction treatment with t-butyl methyl ether and the washing with water are not carried out, the conversion rate is low and the yield is remarkably low.

Example 2 <Ethynylation step> N was used as a reaction solvent in a 1.1 L reactor.
-Methylpyrrolidone 633 g and potassium hydroxide 80 g as a catalyst were added, and cyclopentanone 110 g (1.
33 mol) and acetylene were fed and reacted. The supply of cyclopentanone, which is a raw material, was carried out over 3 hours from the start of the supply, the reaction time with acetylene was 4 hours from the start of the supply of cyclopentanone, and the reaction pressure was 0.02 MPa, The reaction temperature was 20 ° C. After the reaction, water was added to the obtained reaction mixture in an amount corresponding to 1/3 of the liquid volume to stop the reaction.

When the product mixture was analyzed, the conversion of cyclopentanone was 99.4% and the yield of 1-ethynyl-1-cyclopentanol was 74.3%.

<Extraction Step> Next, with respect to 980 g of a liquid of this reaction mixture containing water, t-thrate equivalent to 2/3 of this liquid amount is obtained.
Butyl methyl ether was added. After stirring the liquid, it was left to stand and separated into two layers of an organic phase and an aqueous phase. The separated aqueous layer was extracted once again, the organic layer was collected, and added to the first organic layer. 1-ethynyl-1 by two extraction operations
-Cyclopentanol extraction was 73.8%.

<Washing Step> Next, 950 g of the extracted organic layer and 1/3 amount of water of this solution were added and washed with water. That is, the liquid to which water was added was stirred and then separated, and the organic layer was recovered. This operation was repeated twice more. When the obtained organic layer was analyzed, the recovery rate of 1-ethynyl-1-cyclopentanol was 81.5%.

<Hydrogenation Step> Palladium on carbon (palladium 0.015 g) as a hydrogenation catalyst was added to the organic layer washed with water as described above, and the hydrogenation reaction was carried out for 22 hours in the same manner as in Example 1. . 1-by hydrogenation reaction
100% conversion of ethynyl-1-cyclopentanol
And the yield of 1-ethyl-1-cyclopentanol was 99.5%.

Example 3 <Ethinylation Step> In Example 2, the reaction solvent was 1,
Except that it was replaced with 3-dimethyl-2-imidazolidinone.
Reaction was carried out in the same manner as in Example 2.

<Extraction Step> The reaction mixture obtained above was extracted with t-butyl methyl ether in the same manner as in Example 2. However, the extraction operation with t-butyl methyl ether was only once. As a result of the analysis, 1-
Ethynyl-1-cyclopentanol extraction rate is 97.5%
Met.

<Washing Step> Then, 1530 g of the organic layer thus extracted was washed with water by adding 1/4 amount of water of this liquid. That is, after stirring the liquid to which water has been added, the liquid is separated,
The organic layer was collected. This operation was repeated twice more.
When the obtained organic layer was analyzed, 1-ethynyl-1-
The recovery of cyclopentanol was 81.5%.

<Hydrogenation Step> Using an organic layer washed with water,
The hydrogenation reaction was carried out for 8 hours in the same manner as in Example 1. The conversion rate of 1-ethynyl-1-cyclopentanol by the hydrogenation reaction was 100%, and the yield of 1-ethyl-1-cyclopentanol was 70.6%.

Example 4 <Ethynylation Step> 35 g of 2-adamantanone as a raw material of ketone and dimethyl sulfoxide 655 as a reaction solvent.
g and 3.12 g of potassium hydroxide as a catalyst, the reaction with acetylene was carried out for 4 hours under the same reaction conditions as in Example 1. The raw material ketone was dissolved in 420 g of the solvent and introduced into the reactor over 15 minutes using a pump.

As a result of the analysis, the conversion rate of 2-adamantanone was 98.7% and the yield of 2-ethynyl-2-adamantanol was 90.1%.

<Extraction Step> 300 g of this reaction mixture was treated with t-butyl methyl ether 203 in the same manner as in Example 2.
Extraction treatment was carried out with g. However, the extraction operation with t-butyl methyl ether was only once. As a result of the analysis, 2-
Extraction rate of ethynyl-2-adamantanol is 80.1%
Met.

<Washing Step> Next, the obtained organic layer 21
Water equivalent to ⅕ of this liquid was added to 0 g and washed with water. That is, the liquid to which water was added was stirred and then separated, and the organic layer was recovered. This operation was repeated twice more. When the organic layer thus obtained was analyzed, the recovery of 2-ethynyl-2-adamantanol was 75.8%.

<Hydrogenation Step> The hydrogenation reaction of the above organic layer was carried out for 4 hours in the same manner as in Example 1. The result of the analysis,
The conversion of 2-ethynyl-2-adamantanol is 100.
%, And the yield of 2-ethyl-2-adamantanol was 99.0%.

Example 5 <Ethynylation Step> The ethynylation step was carried out under the same conditions as in Example 4.

<Extraction Step> The reaction mixture obtained above was extracted with toluene in the same manner as in Example 2.
However, the extraction operation with toluene was only once. As a result of the analysis, the extraction rate of 2-ethynyl-2-adamantanol was 71.8%.

<Washing Step> Next, 300 g of the extracted organic layer and 1/3 of the amount of this solution were added and washed with water.
That is, the liquid to which water was added was stirred and then separated, and the organic layer was recovered. This operation was repeated twice more. When the obtained organic layer was analyzed, the recovery rate of 2-ethynyl-2-adamantanol was 81.3%.

<Hydrogenation Step> The hydrogenation reaction was performed on the above organic layer for 8 hours in the same manner as in Example 1. The result of the analysis,
The conversion of 2-ethynyl-2-adamantanol is 100.
%, And the yield of 2-ethyl-2-adamantanol was 89.6%.

Example 6 <Ethynylation Step> Acetylene was produced in the same manner as in Example 4 except that 65 g of adamantane and 635 g of 1,3-dimethyl-2-imidazolidinone were used as the reaction solvent instead of dimethyl sulfoxide. Was reacted for 6 hours.

As a result of the analysis, the conversion rate of 2-adamantanone was 99.8%, and the yield of 2-ethynyl-2-adamantanol was 90.9%.

<Extraction Step> The above-mentioned reaction mixture was extracted once with isopropyl ether in the same manner as in Example 2. As a result of the analysis, the extraction rate of 2-ethynyl-2-adamantanol was 97.2%.

<Water washing step> Next, the obtained organic layer 40
To 0 g, 1/3 amount of water of this solution was added and washed with water. That is, the liquid to which water was added was stirred and then separated, and the organic layer was recovered. This operation was repeated twice more. When the organic layer thus obtained was analyzed, the recovery of 2-ethynyl-2-adamantanol was 82.1%.

<Hydrogenation Step> The hydrogenation reaction of the above organic layer was carried out for 8 hours in the same manner as in Example 1. The result of the analysis,
The conversion of 2-ethynyl-2-adamantanol is 100.
%, And the yield of 2-ethyl-2-adamantanol was 97.0%.

[0052]

INDUSTRIAL APPLICABILITY In the method for producing an ethyl group-containing alicyclic tertiary alcohol via an ethynylated alicyclic tertiary alcohol obtained by reacting a ketone with acetylene, an ethynylated alicyclic tertiary alcohol is used. Good hydrogenation of alcohol can be achieved, and ethyl group-containing alicyclic tertiary alcohol can be obtained in high yield.

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Claims (6)

[Claims] 1. A method for producing an ethyl group-containing alicyclic tertiary alcohol, which comprises performing the following steps in the following order: (1) In a solvent (A) in the presence of an alkali catalyst. A step of producing an ethynylated alicyclic tertiary alcohol by reacting a cyclic ketone with acetylene, (2) compatibility of the obtained ethynylated alicyclic tertiary alcohol with the ethynylated alicyclic tertiary alcohol And a low compatibility with the solvent (A) and water, which does not inhibit the activity of the hydrogenation catalyst in the subsequent hydrogenation step (B), (3) Ethynylated alicyclic group A step of washing the solvent (B) layer containing a trialcohol with water, (4) a step of hydrogenating the ethynylated alicyclic tertiary alcohol in the solvent (B). 2. The cyclic ketone is cyclopentanone,
The production method according to claim 1, which is cyclohexanone or adamantane. 3. The solvent (A) is selected from N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, 2-imidazolidinones, acetonitrile and dimethylsulfoxide. Manufacturing method. 4. The method according to claim 1, wherein the solvent (B) is selected from the group consisting of ethers, saturated aliphatic hydrocarbons, and aromatic hydrocarbons. 5. The production method according to claim 1, wherein the solvent (B) is selected from diethyl ether, dipropyl ether, diisopropyl ether, t-butyl methyl ether and toluene. 6. The production method according to claim 1, wherein the alkali catalyst is an alkali metal hydroxide.