JP2003192626A - Method for producing 2-adamantanone - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To develop a method for producing 2-adamantanone in a high yield and purity without producing nonvolatile tar. <P>SOLUTION: This method for producing the 2-adamantanone comprises oxidizing at least one kind selected from adamantane, 1-adamantanol and 2- adamantanol in concentrated sulfuric acid. In the method, an alcohol such as t-butyl alcohol is added to a reaction medium in the course of the reaction, preferably in the end region of formation of the 2-adamantanone. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing 2-adamantanone which is useful as an intermediate for medical and agricultural chemicals, a raw material for electronic materials and the like.

[0002]

BACKGROUND OF THE INVENTION 2-adamantanone is a compound useful as a raw material for electronic materials and as an intermediate for medicines and agricultural chemicals. For example, it has been reported that a resist obtained by using an alkyladamantyl ester compound as a raw material has high dry etching resistance in a semiconductor manufacturing process (for example, Japanese Patent Laid-Open No. 5-2.
65212), and its potential as a resist material for semiconductors is drawing attention. However, 2-adamantanone is an important compound as a raw material for the alkyladamantyl ester compound.

Due to its use as a raw material for such resist materials for semiconductors, 2-adamantanone is highly required to be highly purified. Further, in the field of electronic materials and the like, competition is fierce and demands for manufacturing cost reduction are becoming severe. That is, for 2-adamantanone, it is extremely important to obtain a highly pure product by a simple method using inexpensive raw materials.

Conventionally, as a method for obtaining 2-adamantanone, a method has been known in which adamantane is oxidized with concentrated sulfuric acid and then purified by steam distillation (Organic Synthesis, 1973, p. 53, page 8, JP-A-11-189).
564 publication).

Further, 2-adamantanol easily undergoes a disproportionation reaction in sulfuric acid to give 1: 1 adamantane and 2
-Adamanthanone is produced, and further 1-adamantanol undergoes a rearrangement reaction in sulfuric acid to easily produce the 2-adamantanol. It is also known to carry out a reaction similar to the oxidation reaction of (for example, tetrahydrone 1968 24, 5361-
5368 pages).

[0006]

Although these methods for obtaining 2-adamantanone by sulfuric acid oxidation of adamantane can obtain 2-adamantanone in a relatively high yield,
A large amount of non-volatile tar was produced. In particular, when the reaction temperature is increased in order to improve the yield in the end region of the reaction in which the consumption of adamantane decreases, the amount of non-volatile tar component produced increases, which is a serious problem. This tar content is obtained by steam distillation or Japanese Patent Application No. 2000-1.
A special extraction method such as 29295 has to be adopted for purification, resulting in complicated operation.

On the other hand, as a method of obtaining 2-adamantanone without using the concentrated sulfuric acid, a method of oxidizing adamantane with oxygen using hydroxyphthalimide or the like is known (Japanese Patent Laid-Open No. 309469/1998, etc.). However, the yield was low at about 30%, which was not satisfactory.

From the above background, it has been a major problem to develop a method for producing 2-adamantanone in a high yield and a high purity without generating a non-volatile tar component.

[0009]

Means for Solving the Problems The present inventor has conducted earnest research to solve the above problems. As a result, when at least one selected from adamantane, 1-adamantanol, and 2-adamantanol is subjected to an oxidation reaction in concentrated sulfuric acid, the above problem is solved by adding alcohol to the reaction solution during the reaction. The inventors have found out what can be done and have completed the present invention.

That is, the present invention relates to adamantane, 1-
In a method for producing 2-adamantanone by oxidizing at least one selected from adamantanol and 2-adamantanol in concentrated sulfuric acid, alcohol is added to the reaction solution during the reaction. This is a method for producing adamantane.

The present invention also relates to 2-adamantanone obtained by the above method, and (1) alkyllithium,
(2) Grignard reagent, and (3) alkyl halide compound and at least one alkylating reagent selected from metallic lithium are reacted to obtain an alkyladamantyl alkoxide compound, and then the alkyladamantyl alkoxide compound and an acid halide or There is also provided a method for producing an alkyladamantyl ester compound, which comprises reacting with an acid anhydride.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The method of the present invention uses any of adamantane, 1-adamantanol, and 2-adamantanol (hereinafter, these raw materials are also collectively referred to as adamantane, etc.) as a reaction raw material to form a concentrated solution. By reaction in sulfuric acid,
2-adamantanone can be produced well.
That is, first, 2-adamantanol is easily oxidized in concentrated sulfuric acid or causes a disproportionation reaction with a molar ratio of 1: 1 to produce adamantane and the desired product, 2-adamantanone. In addition, 1-adamantanol easily undergoes a rearrangement reaction in sulfuric acid to be converted into 2-adamantanol. Furthermore, adamantane is easily oxidized to 1-adamantanol and 2-adamantanol in concentrated sulfuric acid.

Therefore, using any of the above raw materials,
Eventually, a reaction of producing 2-adamantanone from the 2-adamantanol occurs, and the target compound accumulates in the reaction solution.

Of course, even if two or more kinds of these are mixed and subjected to the reaction, 2-adamantanone is satisfactorily formed.

In the present invention, concentrated sulfuric acid is 90 to 100.
A mass% is meant. If the concentration is too high, the amount of tar produced increases, and if the concentration is too low, the oxidizing power tends to decrease, so 95% to 98% concentrated sulfuric acid is preferably used. As these concentrated sulfuric acids, reagents or industrially easily available ones can be used without any limitation, and those having a high concentration can be adjusted by adding fuming sulfuric acid or the like to a low concentration sulfuric acid.

The amount of concentrated sulfuric acid used in the present invention is not particularly limited, but even if it is used in a large excess, the effect commensurate with the amount used is not obtained, and if the amount used is too small, the oxidizing power decreases. However, since the ability to suspend reaction raw materials such as adamantane decreases, it is used in an amount 3 to 500 times, preferably 5 to 300 times the amount of adamantane or the like.

The oxidation reaction for obtaining 2-adamantanone can be carried out in the absence of a solvent, but can also be carried out in an organic solvent. As the solvent used in the present invention, an organic solvent which is incompatible with water, does not inhibit the reaction, and dissolves adamantane, 1-adamantanol, and 2-adamantanol can be used without any limitation.
Specific examples of these organic solvents include halogenated aliphatic hydrocarbons such as methylene chloride, chloroform and carbon tetrachloride; halogenated aromatic hydrocarbons such as chlorobenzene; aliphatic carbonization such as hexane and heptane. Hydrogens;
Aromatic hydrocarbons such as benzene, xylene and toluene;
Examples thereof include ethers such as diethyl ether and diisopropyl ether; esters such as ethyl acetate, propyl acetate and butyl acetate; carbonates such as dimethyl carbonate.

Among these, halogenated aliphatic hydrocarbons and halogenated aromatic hydrocarbons, which can be expected to have particularly high yields, are preferably adopted.

The amount of these organic solvents used in the present invention is not particularly limited, but if the amount is too large, the yield per batch will be small, which is not economical. If the amount is too small, the adamantane and the like will be dissolved. Since it is not possible to make it possible to reduce the reaction rate, normally, for the whole reaction solution,
It is preferable to use the organic solvent such that the amount of adamantane or the like is 0.1 to 60% by mass, preferably 1 to 50% by mass.

The greatest feature of the present invention is that alcohol is added to the reaction solution during the reaction in the reaction for obtaining 2-adamantanone from such adamantane.
This makes it possible to significantly reduce the generation of non-volatile tar components.

That is, in the above production method, the cause of the non-volatile tar component being produced during the reaction is that the non-volatile tar component is present in the reaction solution from the reaction mechanism during the reaction.
-It is considered that this is caused by the side reaction of adamantanol and 2-adamantanone to form a ketal. That is, it is presumed that this ketal inhibits the reaction of producing 2-adamantanone and actively polymerizes to give a large amount of tar content when high thermal energy is applied.

On the other hand, when alcohol is added to the reaction solution as described above, the ketal is decomposed by the action of the alcohol and the generation of the tar component is suppressed, and the decomposition product of the ketal is 2-adaman. Since it is tanone or 1-adamantanol, the yield of the target product is greatly increased. Therefore, according to the present invention, the target 2-adamantanone can be produced in a high yield and a high selectivity with almost no generation of tar components that complicate the purification process.

As the alcohol to be used, known alcohols can be used without particular limitation, but preferably, they have 1 to 6 carbon atoms.
The primary alcohols, secondary alcohols, and tertiary alcohols having an alkyl group and an aralkyl group are preferred. Specifically, methanol, ethanol, 1
-Propanol, n-butanol, 1-pentanol,
Primary alcohols such as 1-hexanol, benzyl alcohol, phenylethyl alcohol and phenylpropyl alcohol; isopropanol, s-butanol, 2
-Secondary alcohols such as pentanol, 3-pentanol, 2-hexanol and 3-hexanol; and tertiary alcohols such as t-butanol and triphenylmethyl alcohol.

Among these, methanol, ethanol, 1-propanol, n-
Butanol, 1-pentanol, 1-hexanol, benzyl alcohol, phenylethyl alcohol, isopropanol, s-butanol, 2-pentanol, 3-
Pentanol, 2-hexanol, 3-hexanol,
T-butanol, triphenylmethyl alcohol and the like are preferable, and tertiary alcohols such as t-butanol and the like are most preferable.

The amount of these alcohols added is not particularly limited, but if the amount is too large, side reactions are promoted, and if the amount is too small, the ketal cannot be decomposed. Therefore, it is 0 per 1 mol of the adamantane used as a raw material. 0.01 mol to 10 mol, preferably 0.02 mol to 5 mol, more preferably 0.0
It is preferably 3 mol to 2 mol.

In the present invention, the alcohol may be added to the reaction solution at any time during the reaction is completed. At the beginning of the reaction, alcohol may be oxidized by concentrated sulfuric acid, which may cause a side reaction.
It is preferable to add alcohol to the reaction solution in the final region of 2-adamantanone production to continue the reaction. Specifically, after the adamantane concentration in the reaction solution becomes 2% by mass or less, preferably 1% by mass or less as measured by gas chromatography, that is, the adamantane concentration in the reaction solution becomes the above value. It is preferable to add it during the period from the time when it cannot be confirmed by measurement by gas chromatography or the like.

When the reaction liquid reaches a state where adamanne cannot be confirmed in the reaction liquid, it is preferable to add alcohol as quickly as possible, but the temperature of the reaction liquid is 70 ° C. or lower, preferably 60 ° C. or lower. In the case where the temperature is kept at 1, the rate of generation of the tar component is gradual, so the effect of the present invention is sufficiently exerted only after an extremely long time has elapsed. Preferably, within 5 hours after reaching the state where the adamantane cannot be confirmed, more preferably 2
It is desirable to add alcohol within the time.

In the present invention, the reaction temperature including the period after the alcohol is added to the reaction solution is not particularly limited, but if the temperature is too high, the by-product of the tar content is promoted, and if the temperature is too low, the reaction occurs. Usually 10 due to reduced speed
C. to 80.degree. C., preferably 20.degree. C. to 70.degree. C. Further, a better effect can be obtained by determining the temperature raising method as described in JP-A No. 11-189564. Especially after adding alcohol to the reaction solution, 30
It is preferable to set the reaction temperature to -50 ° C from the viewpoint of further reducing the generation of tar components. In the present invention, it is advantageous that the yield of 2-adamantanone can reach an extremely high value due to the decomposition of the ketal even under mild temperature conditions after the alcohol is added to the reaction solution.

After the alcohol is added to the reaction solution, the final end point of the reaction is confirmed by measuring the concentration of 1-adamantanol in the reaction solution by gas chromatography or the like, and the concentration of the compound is 3% by mass. Below, preferably 2
It may be set when it is reduced to less than mass%. Generally, after adding alcohol to the reaction solution, it is preferable to hold it for 0.5 to 5 hours, preferably 1 to 2 hours. The overall reaction time is not particularly limited, but it cannot be generally stated because it varies depending on the sulfuric acid concentration used or the reaction temperature, but is usually 0.5.
~ 100 hours is sufficient.

The reaction pressure may be any of normal pressure, reduced pressure and increased pressure, and the reaction liquid is preferably stirred.

The operating procedure for carrying out the present invention is not particularly limited except that alcohol is added during the reaction, and any procedure may be used. Usually, concentrated sulfuric acid adjusted to a predetermined concentration is charged in a reaction vessel, and then a predetermined amount of adamantane or the like is added, and various reaction conditions such as temperature are set to carry out the reaction.

The method for isolating and purifying 2-adamantanone from the reaction solution is not particularly limited and a known method can be adopted. In the present invention, since the reaction solution contains almost no tar content, highly pure 2-adamantanone can be obtained by a simple method without performing a complicated purification operation such as steam distillation. . For example, the reaction solution after the reaction may be poured into ice and the precipitated crystals may be filtered or centrifuged, extracted with a solvent, washed, and the solvent distilled off,
After drying, the residue is subjected to silica gel column chromatography,
It can also be separated and purified by a treatment such as recrystallization.

In the present invention, the 2-adamantanone thus obtained is, for example, a pharmaceutical intermediate, a raw material of a photoresist monomer, a raw material of a photochromic compound, a paint, an adhesive, a pressure-sensitive adhesive, a film, an adsorbent, etc. It can be usefully used as various industrial materials such as the raw material of the above materials. For example, it is preferably used as a raw material for producing an alkyladamantyl ester compound.

The alkyl adamantyl ester compound is
For example, it is known that a resist manufactured using this as a raw material has high dry etching resistance in a semiconductor manufacturing process (for example, Japanese Patent Laid-Open No. 5-265212).
Gazette), and its potential as a semiconductor resist material is drawing attention. The 2-adamantanone obtained in the present invention is extremely high in purity due to the difficulty in producing tar and the like. Therefore, when used as a raw material for producing the alkyladamantyl ester compound, the compound has a good yield, The advantageous effect of being obtained in high purity is exhibited.

The reaction for obtaining an alkyladamantyl ester compound from 2-adamantanone will be described below.

In the present invention, the production of an alkyl adamantyl ester compound using 2-adamantanone is carried out by using the 2-adamantanone, (1) alkyl lithium, (2) Grignard reagent, and (3) alkyl halide. It is preferable to carry out by a method of reacting a compound and at least one alkylating reagent selected from lithium metal to obtain an alkyladamantyl alkoxide compound, and then reacting the alkyladamantyl alkoxide compound with an acid halide or acid anhydride. .

The alkylating reagent used in this reaction is at least one selected from (1) alkyl lithium, (2) Grignard reagent, and (3) halogenated alkyl compound and metallic lithium (ie, a combination of both). The compound is not particularly limited as long as it is used, and various compounds depending on the kind of the alkyl group to be introduced are appropriately used.

Specific examples of compounds that can be suitably used as the alkylating reagent include methyllithium, ethyllithium, butyllithium, etc. as the alkyllithium; methylmagnesium bromide, ethylmagnesium chloride, etc. as the Grignard reagent. Examples of the alkyl halide include methyl iodide and ethyl bromide.

The method for obtaining the alkyladamantyl alkoxide compound by reacting these alkylating reagents with 2-adamantanone is not particularly limited. For example, an approximately equimolar or a small excess of alkylating reagent to 2-adamantanone is used. It can be suitably carried out by reacting in an organic solvent. As the solvent at this time, a known organic solvent can be used without limitation as long as it does not react with the alkylating agent. Examples of organic solvents that can be suitably used include ether solvents such as diethyl ether, tetrahydrofuran, ethylene glycol dimethyl ether, and hydrocarbon solvents such as hexane and toluene.

The reaction conditions for the above reaction are not particularly limited, but the amount of the alkylating reagent used is 0.9 to 1.5 mol, especially 1.0 to 1.0 mol per 1 mol of 2-adamantanone.
It is preferably 1.3 mol. However, when the combination of the halogenated alkyl compound of the above (3) and metallic lithium is used as the alkylating reagent, the suitable amount of each of these reagents is 2 mol of 2-adamantanone, respectively. 0.8-2.0 mol and 1.5-2.5 gram atom, especially 1.0-1.2 mol and 1.8-2.0 gram atom.

The reaction temperature is not particularly limited and may be appropriately determined depending on the type of alkylating agent used. When the alkylating reagent of (1) or (2) above is used, the reaction temperature is usually 20 to 80 ° C. Be seen. Further, in the case of using the alkylating agent of the above (3), when iodide is used as the alkyl halide, it is preferable to react at −80 to 20 ° C., and when using bromide or chloride, 0 is used. It is preferable to react at -100 ° C. further,
The reaction time is usually 0.5 to 24 hours, though it depends on the type of alkylating agent used.

The alkyladamantyl alkoxide compound thus obtained is generally used for the reaction with an acid halide or an acid anhydride without isolation. As the acid halide or acid anhydride used at this time,
An acid halide or acid anhydride having a corresponding structure may be used depending on the kind of the target alkyl adamantyl ester compound.

Examples of acid halides that can be preferably used include acetyl chloride, methacrylic acid chloride and benzoyl chloride. On the other hand, examples of acid anhydrides that can be preferably used include acrylic acid anhydride and methacrylic acid anhydride.

The reaction method of the alkyladamantyl alkoxide compound and the acid halide or acid anhydride is not particularly limited, and a known method can be used. For example, it can be suitably carried out by mixing both in the presence of a solvent. At this time, the amount of the acid halide used is 0.9 with respect to 1 mol of the alkyladamantyl alkoxide compound.
It is preferable to use ˜2.0 mol, especially 1.0 to 1.3 mol.

When the acid halide is used in an excessive amount, it is possible to add 1 mol or more of the tertiary amine compound to 1 mol of the excess acid halide, which is a particular object. When the alkyladamantyl ester compound is unstable to acid, it is more preferable to add such an amount of the tertiary amine compound. At this time, the tertiary amine compound is not particularly limited, but triethylamine, pyridine, dimethylaminopyridine, diazabicyclo [2.2.2. ] Octane etc. can be used.

The amount of the acid anhydride used is 0.8 to 1 mol with respect to 1 mol of the alkyladamantyl alkoxide compound.
It is preferable to use 2.0 mol, particularly 0.9 to 1.3 mol.

The reaction temperature and reaction time depend on the type of acid halide or acid anhydride, but when an acid halide is used, it is generally 0.5 to 20 ° C. to 100 ° C.
The reaction may be performed for about 24 hours. On the other hand, when an acid anhydride is used, the reaction temperature is 0 ° C to
It is preferable to react at 40 ° C. for 0.5 hours to 6 hours.

The alkyl adamantyl ester compound thus obtained is subjected to usual post-treatments such as washing with water, drying, distilling off the solvent and the like, and subjected to usual purification methods such as silica gel column chromatography, distillation and recrystallization. It can be isolated by using the method.

[0049]

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

Example 1 13.6 g of adamantane was added to 184 g of 96% concentrated sulfuric acid, heated to 50 ° C. with vigorous stirring, reacted for 5 hours, and then heated to 60 ° C. After heating to 60 ° C., the reaction solution was sampled every 30 minutes, and the adamantane concentration in the reaction solution was measured. After 20 hours of reaction, adamantane was detected by gas chromatography (hereinafter referred to as G
Since it was confirmed that the content of C was 1% by mass or less, it was cooled to 30 ° C., and 1.48 g of tert-butyl alcohol (an amount corresponding to 0.1 mol with respect to 1 mol of adamantane charged). ) Added. The mixture was stirred at 30 ° C. for 1 hour, and it was confirmed that 1-adamantanol was 2% by mass or less by GC, and the mixture was cooled.

Then, when the reaction solution was poured into 400 g of ice and extracted with 400 ml of dichloromethane, it was visually confirmed that precipitation of solid matter insoluble in dichloromethane was slight, and saturated sodium hydrogencarbonate water and 10% saline solution were added. It was washed with and dried over magnesium sulfate, and then dichloromethane was distilled off. The pale yellow crystalline 2-adamantanone was 13.
2 g (yield 88%) was obtained, and GC analysis using dodecane as an internal standard revealed a purity of 96.1%.

Example 2 In Example 1, 15.2 g of 1-adamantanol was reacted in 161 g of 96% concentrated sulfuric acid at 50 ° C. for 17 hours.
After confirming that the amount of adamantane is 1% by mass or less on GC, add tert-butyl alcohol to 1.48.
The same operation as in Example 1 was performed except that g was added.

As a result, solids insoluble in dichloromethane were not found at the time of extraction with dichloromethane, 13.5 g (yield 90%) of 2-adamantanone of pale yellow crystals was obtained, and the purity was 97.7%. It was

Example 3 In Example 1, 15.2 g of 2-adamantanol
Was reacted in 163 g of 96% concentrated sulfuric acid at 50 ° C. for 15 hours, and after confirming that adamantane was 1% by mass or less on GC, tert-butyl alcohol was added to 1.
The same operation as in Example 1 was performed except that 48 g was added.

As a result, solids insoluble in dichloromethane were not observed at the time of extraction with dichloromethane, 13.6 g (yield 91%) of 2-adamantanone of pale yellow crystals was obtained, and the purity was 97.8%. It was

Examples 4 to 10 Examples of Example 1 except that the alcohol shown in Table 1 was added in place of tert-butyl alcohol in an amount corresponding to 0.1 mol per 1 mol of adamantane charged. The same operation as in 1 was performed. In any of the Examples, solid matter insoluble in dichloromethane was not observed at the time of extraction with dichloromethane, or the amount of precipitation was slight even if observed.

The above results are shown in Table 1.

[0058]

[Table 1]

Example 11 The same as Example 1 except that the amount of tert-butyl alcohol used was 11.8 g (equivalent to 0.8 mol with respect to 1 mol of adamantane charged). The operation was performed.

As a result, solids insoluble in dichloromethane were precipitated only slightly during extraction with dichloromethane, and 12.4 g of 2-adamantanone as pale yellow crystals (yield 85%).
Was obtained and the purity was 96.5%.

Comparative Example 1 To 184 g of 96% concentrated sulfuric acid, 13.6 g of adamantane was added, heated to 50 ° C. with vigorous stirring, reacted for 5 hours, and then heated to 60 ° C. After heating to 60 ° C, the reaction solution was sampled every 30 minutes, and the adamantane concentration in the reaction solution was measured. After 20 hours of reaction, it was confirmed that the adamantane was 1% by mass or less by GC. , Further heat to 70 ° C and stir for 3 hours,
It was confirmed that 1-adamantanol was 2% by mass or less by GC, and the mixture was cooled.

Then, the reaction solution was poured into 400 g of ice and extracted with 400 ml of dichloromethane. At that time, a large amount of tar-like solid material insoluble in dichloromethane was deposited. Then, it was washed with saturated aqueous sodium hydrogencarbonate solution and 10% saline solution, dried over magnesium sulfate, and then dichloromethane was distilled off. Light yellow crystalline 2-adamantanone is 9.75.
g (yield 65%) was obtained, and G was obtained by using dodecane as an internal standard.
When analyzed by C, the purity was 88.0%.

Comparative Example 2 1-adamantanol 15.2 in 163 g of 96% concentrated sulfuric acid
g and heat to 50 ° C. with vigorous stirring,
After reacting for 60 hours, the mixture was stirred at 60 ° C. for 3 hours and at 70 ° C. for 2 hours, and it was confirmed that 1-adamantanol was 2% by mass or less by GC, and the mixture was cooled.

Then, the reaction solution was poured into 400 g of ice and extracted with 400 ml of dichloromethane. At that time, a large amount of a solid substance insoluble in dichloromethane was deposited. Then, it was washed with saturated aqueous sodium hydrogencarbonate solution and 10% saline solution, dried over magnesium sulfate, and then dichloromethane was distilled off.
10.5 g of 2-adamantanone of pale yellow crystal (yield 7
It was obtained, and the GC analysis using dodecane as an internal standard revealed a purity of 94.8%.

Example 11 7.5 g (50 g) of 2-adamantanone obtained in Example 1
mmol) in tetrahydrofuran (25 mL),
50 mL of a previously prepared solution of methylmagnesium bromide in tetrahydrofuran (1 mol / L) was added dropwise at 40 ° C. or lower. After confirming the progress of the reaction by GC, 1.25 g (12.5 mmol) of triethylamine and 7.5 g (75 mmol) of methacrylic acid chloride were added to the reaction solution to give 5
The mixture was stirred at 0 ° C for 3 hours.

After confirming the progress of the reaction by GC, 5 mL of water was added to stop the reaction. Then, the tetrahydrofuran was distilled off under reduced pressure, 50 mL of heptane was added, and the mixture was washed successively with a 1N ammonium chloride aqueous solution, a 10% sodium hydroxide aqueous solution, and ion-exchanged water. Then, heptane was distilled off under reduced pressure to obtain a crude product. 0.75 g of diethylene glycol was added to the crude product, and vacuum distillation (92
C./0.4 mmHg), and 7.06 g (yield 60%) of 2-methyl-2-adamantyl methacrylate was obtained.

Example 12 7.5 g of 2-adamantanone (50 g obtained in Example 2)
mmol) in tetrahydrofuran (25 mL),
6 g (55 mmol) of ethyl bromide was added. While vigorously stirring the solution, 0.1 g of lithium metal was added so that the temperature of the solution did not exceed 30 ° C., and the total amount was 0.75 g (8
5 mmol) was added. After confirming the progress of the reaction by GC and visually confirming that the metallic lithium disappeared, 5 g (50 mmol) of methacrylic acid chloride was added to the reaction solution.

After confirming that the reaction proceeded sufficiently by GC, 1.5 mL of methanol and 1.5 mL of 5% aqueous sodium hydroxide solution were added to the reaction solution, and the mixture was stirred at room temperature for 1 hour to stop the reaction. Then, the organic solvent was distilled off under reduced pressure, 100 mL of hexane was added, and the obtained solution was washed successively with a 10% aqueous sodium hydroxide solution and a 20% saline solution. Then, hexane was distilled off under reduced pressure to obtain a crude product, which was recrystallized from isopropanol to obtain 5.21 g of 2-ethyl-2-adamantyl methacrylate (yield 42%).

Example 13 7.5 g of 2-adamantanone (50 g obtained in Example 3)
mmol) in tetrahydrofuran (25 mL),
50 mL of a previously prepared solution of methylmagnesium bromide in tetrahydrofuran (1 mol / L) was added dropwise at 40 ° C. or lower. After confirming the progress of the reaction by GC, 5.34 g (51 mmol) of acrylic acid anhydride was added to the reaction solution, and the mixture was stirred at room temperature for 4 hours.

After confirming the progress of the reaction by GC, 1.5 mL of methanol and 1.5 mL of 5% sodium hydroxide aqueous solution were added at 10 ° C. or lower and stirred for 1 hour, and the organic layer was separated.
The organic layer was further washed with 10% aqueous sodium hydroxide solution, and then the solvent was distilled off to obtain a crude product. When the crude product was distilled under reduced pressure (85 ° C./0.3 mmHg), 2-methyl-2-adamantyl acrylate 7.3 was obtained.
8 g (yield 60%) was obtained.

Example 14 7.5 g (50 mmol) of 2-adamantanone obtained in the same experiment as in Example 2 was added to tetrahydrofuran 25.
It was dissolved in mL and 6 g (55 mmol) of ethyl bromide was added. 0.1 g of metallic lithium while stirring the solution vigorously
Each was added so that the temperature of the solution did not exceed 30 ° C., and a total of 0.75 g (85 mmol) was added. G of reaction progress
After confirming by C that the metallic lithium has disappeared, 5.34 g (51 m) of acrylic acid anhydride was added to the reaction solution.
mol) was added.

After confirming that the reaction proceeded sufficiently by GC, 1.5 mL of methanol and 1.5 mL of 5% aqueous sodium hydroxide solution were added to the reaction solution, and the mixture was stirred at room temperature for 1 hour to stop the reaction. Then, the organic layer is separated, the organic layer is further washed with 10% aqueous sodium hydroxide solution, the organic solvent is distilled off under reduced pressure, and the residue is distilled under reduced pressure to give 2-ethyl-2-.
7.43 g (yield 64%) of adamantyl acrylate was obtained.

[0073]

According to the present invention, when adamantane or the like is oxidized to produce 2-adamantanone, generation of non-volatile tar component can be greatly suppressed. Therefore, high-purity 2-adamantanone can be obtained from the reaction solution by a simple separation and purification operation such as filtration and recrystallization without performing a complicated purification operation such as steam distillation.

Further, the yield of 2-adamantanone is extremely high, and it is industrially very useful.

Claims (4)

[Claims] 1. Adamantane, 1-adamantanol,
And a method for producing 2-adamantanone by oxidizing at least one selected from 2-adamantanol in concentrated sulfuric acid, wherein alcohol is added to the reaction solution during the reaction. Production method. 2. The method for producing 2-adamantanone according to claim 1, wherein alcohol is added to the reaction solution in the final region of 2-adamantanone production to continue the reaction. 3. The end region of the production of 2-adamantanone is
The method for producing 2-adamantanone according to claim 2, which is after the adamantane concentration in the reaction solution becomes 2% by mass or less. 4. 2-adamantanone obtained by the production method according to claim 1, (1) alkyllithium, (2) Grignard reagent, and (3) halogenated alkyl compound And at least one alkylating reagent selected from lithium metal to obtain an alkyladamantyl alkoxide compound, and then reacting the alkyladamantyl alkoxide compound with an acid halide or an acid anhydride. Process for producing ester compound.