JPH0529371B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for purifying organometallic compounds. More specifically, the present invention relates to a method for removing trace amounts of oxygen-containing components or oxygen-containing components and halogen-containing components from organometallic compounds. [Prior Art] Organometallic compounds are useful substances as polymerization catalysts, raw materials for producing olefins, raw materials for higher alcohols, or raw materials for producing electronics. However, ordinary organometallic compounds contain oxygen-containing components such as oxygen or water alone or in combination with organometallic compounds, or halogen molecules alone or in addition to these oxygen-containing components. Halogen-containing components that have reacted with organometallic compounds (hereinafter referred to as impurities)
exists. It is thought that trace amounts of impurities in this organometallic compound are mixed in from the raw material of the organometallic compound or during production, transportation, or storage. The presence of impurities in the organometallic compound causes particular problems when it is used as a raw material for the electronic industry among the above-mentioned applications. For example, it is said that if an aluminum thin film semiconductor is manufactured using an organic aluminum compound containing a trace amount of oxygen, the resistance will be extremely high in the areas where the mixed oxygen is present, resulting in wire breakage, etc.
This results in disadvantages such as a decrease in yield and an inability to obtain a product that maintains the desired performance. Methods such as precision distillation can easily be considered as a method for removing impurities in organometallic compounds, but in this case
Purification and recovery to a purity of 99.9% or higher is inherently difficult. [Problems to be Solved by the Invention] Under such circumstances, the present inventors have conducted intensive research to find an industrial method for highly efficiently removing trace amounts of impurities in organometallic compounds. The present inventors have discovered that it is possible to purify an organometallic compound containing impurities by reacting it with a reducing agent and then separating it by distillation or sublimation, leading to the completion of the present invention. [Means for Solving the Problems] That is, the present invention provides general formulas R ₁ −M ₁ , R ₁ −M ₂ −R ₂ ,

【formula】

[Effect]

To explain the present invention in detail below, the general formula ()
, M ₁ is Li, M ₂ is Mg, Zn, Cd or Te,
_M3 is B, Al, Ga or In, _M4 is Si, Ti, Ge,
Metal such as Zr or Sn, preferably Li,
Organometallic compounds having C1-12 alkyl groups, aryl groups, cycloalkadienyl groups, or hydrogen atoms of metal elements such as Mg, Zn, Cd, Al, Ga, and In are treated. Some examples of the organic compounds include ethyllithium, n-propyllithium, isopropyllithium, n-butyllithium, tert-butyllithium, neopentyllithium, cyclopentadienyllithium, diethylmagnesium, di-n-butylmagnesium, diisobutylmagnesium, ditertiarybutylmagnesium, dicyclopentadienylmagnesium,
bismethylcyclopentadienylmagnesium,
Dimethylzinc, diethylzinc, dimethylcadmium, diethylcadmium, biscyclopentadienylcadmium, trimethylaluminum, triethylaluminum, tri-n-butylaluminum, tri-isobutylaluminum, tri-tert-butylaluminum, dimethylaluminum hydride, diethylaluminum hydride, di-normal Butyl aluminum hydride, diisobutyl aluminum hydride,
Ditertiary butyl aluminum hydride, trimethyl gallium, triethyl gallium,
Examples include diethylcyclopentadienyl gallium, trimethylindium, triethyl indium, dimethylethyl indium, methyl diethyl indium, tricyclopentadienyl indium, and the like. In the purification process of the method of the present invention, the organometallic compound containing trace impurities can be subjected to the purification process alone or as a mixture with an organic solvent. As such organic solvents, saturated aliphatic hydrocarbons such as pentane, hexane, octane, decane, dodecane, heptadecane, paraffin oil, and kerosene, and alicyclic hydrocarbons such as cyclohexane and cyclopentane can be used. When treating an organometallic compound by the method of the present invention, the reducing agent and the organometallic compound containing impurities may be reacted catalytically with stirring. When a solid metal hydride compound is used alone, as a mixture, or as a double salt as a reducing agent, the finer the powder, the better the effect, so it is preferable to pulverize the compound before use. The reaction is generally exothermic, but at temperatures between 0°C and 200°C,
Preferably, it is carried out at a temperature in the range of 10 to 150°C. The reaction time can range from 1 minute to 24 hours, preferably from 10 minutes to 10 hours. The amount of reducing agent added is based on the organometallic compound.
The reaction can be carried out in an amount of 0.1 to 50% (wt), preferably in a range of 1 to 20% (wt). The organometallic compound after the reaction can be used as it is, or if necessary, the unreacted organometallic compound and the reaction product can be separated by standing, filtration, centrifugation, decantation, etc., and then subjected to distillation or sublimation purification. be done. The distillation purification may be appropriately selected from simple distillation, precision distillation, vacuum distillation, etc. depending on the purity, physical properties, etc. of the target organometallic compound. Sublimation purification may be appropriately selected from normal pressure sublimation, reduced pressure sublimation, sublimation using a carrier gas, pseudo-sublimation, etc. depending on the purity and physical properties of the target organometallic compound. [Examples] Hereinafter, the method of the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples unless the gist thereof is exceeded. Example 1 After purging a 300 ml flask equipped with a stirrer and a reflux condenser with nitrogen, 12.0 g of pulverized sodium hydride,
114.8g of trimethyl gallium was charged. The temperature was raised to 50°C while stirring and maintained for 1 hour. Next, this was distilled under normal pressure at 56°C to obtain 83 g of purified trimethyl gallium. Table 1 shows the concentration of oxygen components in the purified trimethyl gallium thus obtained.

[Table] Example 2 After purging a 300 ml flask equipped with a stirrer and reflux condenser with nitrogen, 3.6 g of lithium aluminum hydride,
72.1 g of trimethylaluminum was charged. The temperature was raised to 100°C while stirring and maintained for 1 hour. then this
Distillation was carried out under reduced pressure at 86° C. under 200 mmHg to obtain 50.4 g of purified trimethylaluminum. The concentration of oxygen component in the purified trimethylaluminum thus obtained was <2 ppm. Example 3 A 300 ml flask equipped with a stirrer and a reflux condenser was purged with nitrogen, and 9.6 g of lithium hydride and 96 g of dimethyl zinc were charged therein. Stir and hold at room temperature for 2 hours. Next, this was distilled at 46° C. under normal pressure to obtain 69 g of purified dimethyl zinc. The oxygen component concentration in the purified dimethyl zinc thus obtained is <
It was 2ppm. Example 4 After purging a 300 ml flask equipped with a stirrer and a reflux condenser with nitrogen, 3.2 g of lithium aluminum hydride,
64 g of tertiary butyl lithium and 100 ml of n-hexane were charged. The temperature was raised to 60°C while stirring and maintained for 1 hour. Normal hexane was distilled off from this at normal pressure and 68°C. Next, sublimation was carried out under reduced pressure at 50° C. under 0.1 mmHg to obtain 51.2 g of purified tert-butyllithium. The oxygen component in the tertiary butyl lithium thus obtained is <2 ppm, and the halogen component is <0.5 ppm.
It was hot. Example 5 After purging a 300 ml flask equipped with a stirrer and a reflux condenser with nitrogen, sodium aluminum hydride was added at 5.7 mL.
g, and 114 g of triethylaluminum were charged. The temperature was raised to 80°C while stirring and maintained for 1 hour. next
The pressure was reduced to 10 mmHg and vacuum distillation was performed at 97°C to obtain 91 g of purified triethylaluminum. The oxygen component concentration in the purified triethylaluminum thus obtained was <2 ppm. Example 6 The same procedure as in Example 2 was carried out except that the temperature during treatment was changed to room temperature. The results are shown in Table 2. Example 7 The same procedure as Example 2 was carried out except that the temperature during treatment was changed to 70°C. The results are shown in Table 2. Example 8 The same procedure as in Example 2 was carried out except that the temperature during treatment was changed to 120°C. The results are shown in Table 2.

〔Effect of the invention〕

According to the present invention, an organometallic compound substantially or completely free of impurities can be produced from an organometallic compound containing a trace amount of an oxygen-containing component or a trace amount of an oxygen-containing component and a trace amount of a halogen-containing component, and thus purified. The resulting organometallic compounds can be suitably used in the electronic industry and other fine chemical fields, and their industrial value is enormous.

Claims (1)

[Claims] 1 General formula () R ₁ −M ₁ , R ₁ −M ₂ −R ₂ , [Formula] [Formula] (In the formula, M ₁ is a monovalent element, M ₂ is a divalent element, M ₃ represents a trivalent element, M ₄ represents a tetravalent element, and R ₁ , R ₂ , R ₃ and R ₄ represent the same or different alkyl group, aryl group, cycloalkadienyl group, or hydrogen atom.
However, in the case of M ₁ , the case where R ₁ is a hydrogen atom is excluded. ) and containing a trace amount of an oxygen-containing component, or a trace amount of an oxygen-containing component and a trace amount of a halogen-containing component, is added to 0.1 to 50% (wt) of the organometallic compound under stirring conditions. Corresponding metal hydride compounds such as sodium hydride, potassium hydride,
Lithium hydride, calcium hydride, aluminum hydride, titanium hydride, zirconium hydride or their double salts such as lithium aluminum hydride, sodium aluminum hydride, sodium borohydride, lithium borohydride or sodium diethylaluminum dihydride. By adding a reducing agent selected from at least one type of hydride or a mixture thereof, and then separating the reducing agent and the organometallic compound by distillation or sublimation, the above-mentioned trace amount of oxygen-containing component or trace amount of oxygen-containing component is removed. A method for purifying organometallic compounds characterized by removing components and trace amounts of halogen-containing components. 2. The method for purifying an organometallic compound according to claim 1, wherein the organometallic compound is subjected to the purification treatment as a mixture with an organic solvent.