JP2004075557A - Method for purifying adamantanone - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for purifying adamantanone, by which the adamantanone can efficiently be purified in high purity and in a large amount. <P>SOLUTION: This method for purifying the adamantanone, an evaporable substance, comprises distilling the adamantanone together with a specific solvent to obtain the adamantanone solution as a main distillate, cooling the main distillate to crystallize the adamantanone, and then collecting the crystals to obtain the highly pure adamantanone. By the method, the adamantanone can be purified in a large amount. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for purifying a sublimable substance, adamantanone.
[0002]
[Prior art]
Adamantanone, which is an object to be purified of the present invention, is an important intermediate in pharmaceutical applications and electronic materials applications. Although there is a demand for high purity for both pharmaceutical use and electronic material use, there is no method capable of obtaining sufficient purity in mass purification on an industrial basis because adamantanone is a compound having sublimability.
For example, in the recrystallization method, it is difficult to separate adamantane, which is a raw material when synthesizing adamantanone, and in the sublimation method, it is not suitable for mass purification due to a problem in equipment. In addition, since adamanthanone is a sublimable solid, it cannot be purified by ordinary distillation, and even if it is distilled, the sublimated adamantanone precipitates in the cooling pipe of the distillation apparatus and blocks the distillation line. There is.
Thus, there is no efficient method for purifying a large amount of adamantanone, a sublimable substance, with high purity.
As a purification method for removing a sublimable substance as an impurity, there is a method described in JP-A-2001-97893. The method described in Japanese Patent Application Laid-Open No. 2001-97893 relates to a method of purifying a non-sublimable and high-boiling alkyladamantyl ester from a solution containing a sublimable substance such as adamantane as an impurity. The technical idea is completely different from the method of purifying adamantanone which is a sublimable substance as in the present invention.
[0003]
[Problems to be solved by the invention]
In the method of purifying adamantanone, which is a compound having sublimability, none of the recrystallization method, the sublimation method, and the distillation method simultaneously satisfies sufficient purity and large-scale purification. The present inventors have conducted intensive studies focusing on the advantages and disadvantages of these purification methods, and as a result, have found that adamantanone can be suspended using a solvent having a boiling point close to the sublimation temperature of adamantanone and a low solubility of adamantanone. The main fraction was obtained as a hot adamantanone / solvent solution by performing turbidity and distillation, and then the obtained main fraction was cooled to crystallize adamantanone, and the crystals were collected to obtain purified adamantanone. Thus, it was made possible to purify adamantanone in large amounts with high purity.
As described above, an object of the present invention is to provide an extremely excellent method capable of efficiently purifying adamantanone with high purity in large quantities.
[0004]
[Means for Solving the Problems]
The gist of the present invention made to solve the above problems is as follows:
(1) Adamantanone is mixed with a solvent having a boiling point close to the sublimation temperature of Adamantanone and having low solubility of Adamantanone, followed by distillation to obtain a main fraction as a hot Adamantanone / solvent solution. Cooling the solution to crystallize adamantanone, collecting crystals to obtain a purified adamantanone, and a method for purifying adamantanone;
(2) The method for purifying adamantanone according to the above (1), wherein one or two or more saturated or unsaturated aliphatic hydrocarbons having 10 to 14 carbon atoms are used as a solvent;
It is.
[0005]
BEST MODE FOR CARRYING OUT THE INVENTION
The purification method of the adamantanone of the present invention has a boiling point close to the sublimation temperature of the adamantanone, and distillation is performed according to a normal distillation method in a state where the adamantanone is suspended using a solvent having a low solubility of the adamantanone. Then, the main fraction is cooled and crystallized, and the precipitated crystals are collected to obtain purified adamantanone.
[0006]
In the present invention, the solvent having a boiling point close to the sublimation temperature of adamantane refers to a boiling point close to the sublimation temperature of adamantanone (180 to 210 ° C), ie, 160 to 280 ° C, preferably 210 to 260 ° C. Having a solvent.
When the boiling point of the solvent is lower than 160 ° C., only the solvent is distilled first, so that there is no purification effect. If the boiling point of the solvent is higher than 280 ° C., sublimation of adamantanone starts before the solvent is distilled off, which may cause blockage of the distillation line due to precipitation of crystals on the inner wall of the distillation apparatus or in the cooling pipe.
[0007]
The solvent having a low solubility of adamantanone means a solvent capable of dissolving adamantanone at the time of heating (or heating) but capable of precipitating adamanthanone crystals when cooled to room temperature to about 0 ° C. That is, it is a solvent that can be usually used for recrystallization of adamantanone.
More specifically, a solvent having a solubility of adamantanone at room temperature to about 0 ° C. of 10 w / v% or less, preferably 5 w / v% or less, more preferably 2 w / v% or less is used.
[0008]
The solvent used in the present invention is not particularly limited as long as it satisfies the above conditions, but preferred examples thereof include a saturated or unsaturated aliphatic hydrocarbon having 10 to 14 carbon atoms (for example, decane, undecane, dodecane, tridecane, tetradecane, Decene, undecene, dodecene, tridecene, tetradecene, decadiene, tetradecadiene, decalin, tetralin and the like).
These solvents may be used as a mixture of two or more kinds.
[0009]
The purification method of the present invention can be carried out using a usual distillation method and apparatus, except that a mixture of the above-mentioned solvent and adamantanone is used.
The conditions of normal pressure and reduced pressure at the time of distillation do not matter, but distillation under reduced pressure is preferable because normal pressure requires a high temperature of about 200 ° C., and 100 ° C. under reduced pressure of 2.7 kPa. Distillation in the vicinity becomes possible.
Further, the main fraction is distilled as a hot solution of adamantanone and a solvent, and when cooled, adamantanone is deposited. Therefore, it is desirable to keep the temperature at a level such that adamantanone does not precipitate during distillation.
[0010]
By cooling the main fraction distilled as a hot solution of adamantanone and a solvent, adamanthanone crystals are precipitated.
The method for collecting the precipitated crystals is not particularly limited, and a conventional method can be used, and examples thereof include filtration, centrifugation, and decantation. The filtration method is simple and preferred.
In the present invention, since a solvent having a low solubility of adamantanone is used during distillation as described above, cooling and crystallization of adamantanone can be performed by ordinary cooling and crystallization without any special operation or special equipment. It can be done easily.
[0011]
The liquid after collecting the purified adamantanone can be used as it is in the next distillation. If a solvent having a high solubility of adamantanone was used during distillation, crystals did not precipitate even when the main fraction was cooled, or even if the crystals were precipitated, the amount thereof was small, and after the crystals were collected. Since a large amount of adamantanone remains in the solution, there is a problem that the purification yield is reduced.
[0012]
The collected purified adamantanone may be dried as it is, but can be easily dried by washing with a low boiling point solvent such as hexane or heptane or water, and replacing the solvent used during distillation.
[0013]
【The invention's effect】
As described above, there was no method capable of obtaining sufficient purity in a large-scale industrial-based purification of adamantanone, which is a sublimable compound, but according to the method of the present invention, a method similar to the sublimation temperature of adamantanone was used. By sublimating and distilling adamantanone together with a solvent having a boiling point and a low solubility of adamantanone, clogging of the apparatus by a sublimate can be prevented, and distillation can be performed by the same operation and the same apparatus as ordinary distillation. It becomes possible. In addition, since a solvent having a low solubility of adamantanone is used, adamantanone is crystallized and collected from the main fraction distilled as a hot solution only by cooling.
Therefore, according to the present invention, except for suspending in the above-mentioned solvent and conducting distillation, adamantanone can be produced in a large amount with high purity by the same operation and the same apparatus as general distillation, cooling crystallization, and crystallization. It can be purified.
[0014]
【Example】
Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to the examples.
[0015]
Example 1
In a 500 mL three-necked flask equipped with a thermometer, a stirrer, and a fractionating tube, 0.1% (weight%, the same applies hereinafter) of 1-adamantanol as a sublimable impurity, and 13.9% of impurities of tar and high-boiling substances. After adding 30.0 g of crude adamantane (purity: 86.0%, pure content: 25.8 g) and 300 mL of dodecane and removing a small amount as an initial fraction, distillation was carried out at about 100 ° C. under reduced pressure of about 2.7 kPa. The hot adamantanone / dodecane solution obtained as the main fraction was cooled to around 0 ° C., the precipitated adamantanone was collected by filtration, washed with 300 mL of tap water, dried under reduced pressure, and dried to obtain 19.2 g of purified adamantanone (purity 99). 0.5%, purification yield 74.0%). The purified adamantanone contained 0.1% water, 0.2% dodecane, 1-adamantanol 0.1%, and tar and high-boiling substances 0.1%.
[0016]
Example 2
In Example 1, adamantane was added as a sublimable impurity in an amount of 1.0%, and the composition of the impurities was changed to 1.0% adamantane, 0.1% 1-adamantanol, tar and 13.8% of a high boiling point substance. Purified adamantanone was prepared in the same manner as in Example 1 except that 30.0 g of tanone (purity: 85.1%, pure content: 25.5 g) was used and the initial fraction was removed to about 5% of the total amount. 18.1 g (purity 99.1%, purification yield 70.0%) was obtained. The purified adamantanone contains 0.1% water, 0.2% dodecane, 0.4% adamantane, 0.1% 1-adamantanol, 0.1% tar and high-boiling substances. there were.
[0017]
Example 3
Purification was carried out by the same material and operation as in Example 1 except that a new dodecane was added to the dodecane filtrate of Example 1 to make 300 mL, and 22.3 g of purified adamantanone (purity 99.6%, purification yield 86) 0.0%). The purified adamantanone contained 0.1% of water, 0.1% of dodecane, 0.1% of 1-adamantanol, and 0.1% of tar and high-boiling substances.
[0018]
Example 4
Purification was performed in the same manner as in Example 1 except that tetradecane was used instead of dodecane and washing was performed with 90 mL of heptane instead of 300 mL of tap water in Example 1, and 16.7 g of purified adamantanone (purity: 98) was used. 8.8%, purification yield 64.1%). Heptane contained in this purified adamantanone was 0.2%, tetradodecane was 0.7%, 1-adamantanol was 0.1%, and tar and high-boiling substances were 0.2%.
[0019]
Example 5
Purification was performed in the same manner as in Example 4 except that dodecene was used instead of tetradecane in Example 4, to obtain 12.1 g of purified adamantanone (purity: 99.1%, purification yield: 46.5%). Was. Heptane contained in this purified adamantanone was 0.2%, dodecene was 0.5%, 1-adamantanol was 0.1%, and tar and high-boiling substances were 0.1%.
[0020]
Comparative Example 1
As a comparison with the case where a solvent having a high solubility of adamantane was used, the same operation as in Example 1 was performed except that nitrobenzene was used instead of dodecane in Example 1, and crystals of adamanthanone were precipitated from the main fraction. Did not.
[0021]
Comparative Example 2
In Example 2, when the amount removed as the initial fraction and the content of adamantane remaining in the purified adamantane were compared, the content of adamantane in the purified adamantane in the case where 5% of the total amount was removed as the initial fraction was determined. The ratio was 0.4%, 0.16% when 20% was removed, and was about trace when 40% was removed.

Claims (2)

Adamantanone is mixed with a solvent having a boiling point close to the sublimation temperature of adamantanone and having low solubility of adamantanone, followed by distillation to obtain a main fraction as a hot adamantanone / solvent solution. A method for purifying adamanthanone, comprising cooling to crystallize adamanthanone, collecting crystals, and obtaining purified adamantanone. The method for purifying adamantanone according to claim 1, wherein one or more kinds of a saturated or unsaturated aliphatic hydrocarbon having 10 to 14 carbon atoms are used as the solvent.