JP2543016B2 - Method for producing 1,3-diketone-based organometallic complex - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a 1,3-diketone-based organometallic complex useful as a superconducting material and a dopant material for optical devices.

[0002]

2. Description of the Related Art Conventionally, as a method for forming a single crystal thin film or a polycrystalline thin film, two kinds of methods such as a dry process and a wet process have been used, but a thin film formed by a dry process is more preferable than a wet process. At present, the dry process is frequently used because of its excellent quality.

The dry process includes a physical film forming method such as a vacuum vapor deposition method, an ion plating method and a sputtering method, and a chemical film forming method such as a chemical vapor deposition method (CVD method). Among them, the CVD method is widely used because it is suitable for mass production because it is easy to control the deposition rate, does not need to be deposited in a high vacuum, and is capable of high-speed deposition. In such a CVD method, when the metal thin film is formed by decomposing the vapor of the organometallic complex, a thermal CVD method, a photo CVD method or a plasma CVD method is adopted. Further, in these methods, a 1,3-diketone-based organometallic complex whose organic moiety (ligand) is acetylacetone, dipivaloylmethane, hexafluoroacetylacetone, diisobutyrylmethane or the like is generally used. There is.

As a method for producing the 1,3-diketone-based organometallic complex as described above, a metal salt is reacted with a 1,3-diketone compound in a 50% aqueous ethanol solution, and then concentrated aqueous ammonia is added. A method of depositing a 1,3-diketone-based organometallic complex is known. In addition, since the 1,3-diketone-based organometallic complex obtained by such a production method is in the form of a hydrate, the obtained metal complex is repeatedly recrystallized by a recrystallization method, a sublimation method or a distillation method. The metal complex was refined by sublimation or distillation to improve the purity of the metal complex.

However, when a metal thin film is formed from an organometallic complex by the above-mentioned method, metal impurities are incorporated into the obtained film-forming material due to insufficient purity of the organometallic complex, and the electrical properties and chemistry of the thin film. However, there is a problem that the physical property is deteriorated. Therefore, a method for producing a highly pure 1,3-diketone-based organometallic complex in which impurities, mainly hydrates are thoroughly removed has been demanded.

[0006]

DISCLOSURE OF THE INVENTION The present invention solves the problems of the above-mentioned conventional techniques, and makes it possible to easily mass-produce a high-purity organometallic complex with a simple operation in a 1,3-diketone system. It is intended to provide a method for producing an organometallic complex.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above problems, and as a result, have determined that a predetermined metal is 1,3
In the absence of a solvent that creates an environment in which a hydrate of the impurity metal is formed and reacts with the diketone to form its organic complex, or in a non-polar solvent that does not tend to such It was found that the reaction of the metal simple substance with the 1,3-diketone can suppress the formation of a hydrate as an impurity, and thus the present invention can be achieved.

That is, according to the present invention, a crude metal of a 1,3-diketone-based organometallic complex is produced by reacting a metal simple substance with a 1,3-diketone in the absence of a solvent or in a nonpolar solvent. The present invention provides a method for producing a 1,3-diketone-based organometallic complex, characterized in that the crude crystal is purified by a recrystallization method or the like to obtain a highly purified product.

Further, in the present invention, it is more convenient to use a Group IIA metal selected from the group consisting of barium, magnesium, calcium and strontium as a simple metal to be reacted with 1,3-diketone, and as a non-polar solvent. When an aliphatic hydrocarbon having 5 to 8 carbon atoms such as n-hexane, n-pentane, 2-methylhexane or octane, or an aromatic hydrocarbon having 6 to 9 carbon atoms having a benzene ring such as benzene, toluene or xylene is used. Particularly preferred.

Further, in the present invention, it is more preferable to use acetylacetone, dipivaloylmethane, hexafluoroacetylacetone or diisobutyrylmethane as the 1,3-diketone.

[0011]

The present invention will be described in detail as follows. First, under an inert gas atmosphere, a simple substance of metal and 1,3-diketone, especially acetylacetone, dipivaloylmethane, hexafluoroacetylacetone or diisobutyrylmethane are added under normal pressure in the absence of a solvent or in a nonpolar solvent. The mixture is heated to 20 to 80 ℃ and reacted to prepare an organometallic complex solution. Next, after confirming that the metal simple substance in the solution completely disappeared by the reaction, unreacted 1,3-diketone and nonpolar solvent remaining in the organometallic complex solution were removed to obtain a crude crystal of the organometallic complex. To get

Next, the obtained crude crystals of the organometallic complex are subjected to aliphatic carbonization such as nonpolar solvent, particularly n-pentane, n-hexane, n-heptane, 2-methylhexane or octane, which has 5 to 8 carbon atoms. Hydrogen or benzene, toluene, xylene, or other benzene ring having 6 to 6 carbon atoms
Heat-dissolve or partially-dissolve in 9 aromatic hydrocarbons. Next, the solution is left at room temperature to obtain a recrystallized product or a precipitate, and the obtained recrystallized product or the precipitate is dried under reduced pressure to obtain a highly pure 1,3-diketone-based organometallic complex. Note that it is sufficient to repeat the above recrystallization or precipitation step twice.

The present invention having the above-mentioned contents has the greatest feature in synthesizing an organometallic complex by directly reacting a metal simple substance with a 1,3-diketone in the absence of a solvent or in a nonpolar solvent. Thus, by directly reacting both in the absence of a solvent or in a non-polar solvent, the production of hydrate as an impurity is suppressed and the organometallic complex is highly purified.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited by the following examples.

[0015]

EXAMPLES As an example of the method for producing the 1,3-diketone-based organometallic complex of the present invention, the method for producing bisdipivaloylmethanatobarium will be described below.

First, 4.1 g (30 mmol) of metal barium was added to 2
The mixture was placed in a 00 ml reaction flask, and the inside of the flask was replaced with argon, 20 ml of n-hexane was added, 22 g (120 mmol) of dipivaloylmethane was subsequently added, and the mixture was stirred at 40 ° C. overnight to react with metal barium. After all the metal barium has reacted, n-hexane is distilled off under reduced pressure (1-2 mmHg) at room temperature, and this solution is heated to 100 ° C to reduce the unreacted dipivaloylmethane remaining in the solution under reduced pressure. Distilled off. After distilling off n-hexane and dipivaloylmethane under reduced pressure, the precipitated bisdipivaloylmethanatobarium crude crystal was recrystallized and purified by n-hexane according to a known recrystallization method to produce a hydrate. 7.8 g (yield 52%) of suppressed and highly pure bisdipivaloylmethanatobarium was obtained. In the recrystallization purification, a larger amount of bisdipivaloylmethanatobarium can be recovered by allowing the liquid to dry and performing recrystallization.

The bisdipivaloylmethanatobarium thus obtained was subjected to thermogravimetric measurement (TG) and differential thermal analysis (DTA), and the results are shown in FIG.
The measurement was conducted by continuously raising the temperature to 600 ° C., and thermogravimetric measurement and differential thermal analysis were simultaneously performed in the process. Also, T
In order to estimate the amount of impurities in the measured sample from the G data, T
A differential curve (DTG) of G is taken and also shown in FIG.

[0018]

Comparative Example As a comparative example of the present invention, a conventional method for producing bisdipivaloylmethanatobarium is shown below.

First, 3 g of 4.1 g (30 mmol) of metal barium was added.
The mixture was placed in a 00 ml reaction flask, the inside of the flask was replaced with argon, and 100 ml of ethanol was added to react metal barium to obtain an ethanol solution of barium ethoxide. Next, 11 g (60 mmol) of dipivaloylmethane was added to the solution, ethanol was distilled off under reduced pressure (1-2 mmHg) at room temperature, and the solution was heated to 100 ° C. The dipivaloylmethane in the reaction was distilled off under reduced pressure to obtain 13.1 g (yield 87%) of bisdipivaloylmethanatobarium. After that, since a considerable amount of hydrate was formed in the obtained bisdipivaloylmethanatobarium, a refined product was obtained by repeatedly performing recrystallization purification with n-hexane, but the recrystallization yield was 5
% Or less, which was extremely low.

TG and DTA, that is, thermogravimetric measurement and differential thermal analysis were performed on the bisdipivaloylmethanatobarium before purification, and the results are shown in FIG. In addition,
The measurement was performed by continuously raising the temperature to 600 ° C, and in the process, thermogravimetric measurement and differential thermal analysis were performed simultaneously. Further, in order to estimate the amount of impurities in the measurement sample from the TG data, a differential curve (DTG) of TG was taken and also shown in FIG.

Comparison of the TG and DTA results for bisdipivaloylmethanatobarium produced by the method of the present invention (example) and the conventional method (comparative example), as can be seen from FIG. 1 and FIG. The bisdipivaloylmethanatobarium produced by the method of the present invention has a TG reduction amount (impurity amount) on the low temperature side (200 ° C. or lower).
The TG weight loss of bisdipivaloylmethanatobarium produced by the conventional method is 4.6%, which is much higher than 2%.
In order to reduce it to 2% or less, the purification must be repeated a considerable number of times, which is very inefficient. Further, the total TG loss of bisdipivaloylmethanatobarium produced by the method of the present invention (bisdipivaloylmethanatobarium sublimation amount) showed a large value of 90% or more (94.5%). 87.5% was produced by the conventional method.
Further, in the DTG of bisdipivaloylmethanatobarium produced by the conventional method, the main peak is split into two, which suggests the inclusion of impurities.

[0022]

As a result of the development of the present invention, it has become possible to produce a highly pure 1,3-diketone-based organometallic complex in which the formation of hydrates is suppressed. Further, according to the present invention, since the number of recrystallization steps or the number of precipitation steps is remarkably reduced as compared with the conventional method, it has become possible to mass-produce easily and efficiently.

[Brief description of drawings]

FIG. 1 is a graph showing the results of TG and DTA for a 1,3-diketone-based organometallic complex produced by the method of the present invention.

FIG. 2 is a graph showing the results of TG and DTA for a 1,3-diketone-based organometallic complex produced by a conventional method.

Claims (4)

(57) [Claims] 1. A simple metal is reacted with a 1,3-diketone in the absence of a solvent or in a non-polar solvent to give 1,
A method for producing a 1,3-diketone-based organometallic complex, which comprises producing a crude crystal of a 3-diketone-based organometallic complex and purifying the crude crystal to obtain a highly purified product. 2. The method for producing a 1,3-diketone-based organometallic complex according to claim 1, wherein the elemental metal is a Group IIA metal selected from the group consisting of barium, magnesium, calcium and strontium. 3. The 1,3-diketone organic compound according to claim 1, wherein the nonpolar solvent is an aliphatic hydrocarbon having 5 to 8 carbon atoms or an aromatic hydrocarbon having 6 to 9 carbon atoms and having a benzene ring. Method for producing metal complex. 4. The method for producing a 1,3-diketone-based organometallic complex according to claim 1, wherein the 1,3-diketone is acetylacetone, dipivaloylmethane, hexafluoroacetylacetone or diisobutyrylmethane.