JPS5940837B2 - Method for producing trialkyltin halide and monoalkyltin trihalide - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for producing trialkyltin halides and monoalkyltin trihalides.

Trialkyltin halides, especially tributyltin chloride, are widely used as fungicides, fungicides, marine antifouling poisons, and intermediates thereof.

On the other hand, monoalkyltin trihalides, especially monomethyltin,
Monobutyltin and monooctyltin compounds are used as intermediates for stabilizers for vinyl chloride resins, and the demand for them is increasing. Trialkyltin halide and monoalkyltin trihalide are each produced through separate processes using separate equipment, but monoalkyltin halide is extremely difficult to produce, and even if it is obtained, it is produced under industrially unfavorable conditions. However, the yield is only low.

Furthermore, conventionally, tin chloride is applied to tetraalkyltin at a low temperature around 0°C, and the following reaction formula is obtained:
Although there is a method for obtaining trialkyltin chloride and monoalkyltin trichloride according to the formula (R represents an alkyl group), it is difficult to control the temperature because of the low temperature, which is industrially disadvantageous.

If the above reaction is carried out at a temperature higher than this, for example 80°C, then in addition to the above product, about 2 dialkyltin cyclolades will be produced.
0% contamination, which not only makes purification and separation difficult, but also has the disadvantage that the yield of each product decreases, such as decomposition and unreacted substances remaining. Therefore, it has been extremely difficult to allow the above reaction to proceed completely at a relatively low temperature (30 to 180°C). As a result of intensive research to eliminate these drawbacks, we found that if the reaction between tin tetraalkyl and tin halide is carried out in the presence of an ether compound, the molar ratio is about 1:1, regardless of the reaction temperature or the charging ratio of both raw materials. However, we have found a method that can quantitatively produce trialkyltin halides and monoalkyltin trihalides.

That is, the present invention involves reacting tetraalkyltin and stannic halide in the presence of an ether compound selected from tetrahydrofuran, dioxane, and methoxybutanol to prepare trialkyltin halide and monoalkyltin trihalide in a ratio of about 1:1 (mole). The present invention relates to a method for producing trialkyltin halides and monoalkyltin trihalides, characterized in that they are obtained at a production ratio of (ratio). The additive ether compound to be present in the method of the present invention is not particularly limited, but aliphatic ethers and alicyclic ethers are preferred.

Examples include diethyl ether, dipropyl ether, dibutyl ether, ethyl vinyl ether, methoxybutanol, tetrahydrofuran, and dioxane. Examples of the tetraalkyltin to be reacted with the stannic halide include tetramethyltin, tetraethyltin, tetrapropyltin, tetrabutyltin, tetraamyltin, tetrahexyltin, tetracyclohexyltin, tetraoctyltin, tetradecyltin, and tetradodecyltin. etc.

Examples of the stannic halides include tin tetrachloride, tin tetrabromide, and tin tetraiodide. The amount of the ether compound added in the method of the present invention is normally sufficient if it is at least 2 times the molar amount of the stannic halide, and it may be used in place of the solvent, for example, at least 4 times the molar amount.

Although the method of the present invention is carried out in the presence of an ether compound, an inert solvent such as benzene, toluene, xylene, cyclohexane, n-hexane, etc. may be used if necessary.

Although the reaction temperature is not particularly limited, it can be carried out at an industrially advantageous temperature, for example, within the range of 30 to 180°C.

In order to carry out the reaction smoothly, it may be carried out at the reflux temperature of the additive or solvent. The reaction usually completes in 1 to 2 hours. The method of the present invention is generally carried out as follows.

First, stannic halide is charged into a reaction vessel, and an ether compound additive is added dropwise to the reaction vessel at a speed that does not generate too much heat to form an adduct. The tetraalkyltin is then added to the adduct and heated to complete the reaction. After the reaction, if there is an excess of stannic halide, it forms additives and adducts and precipitates out, so it is washed away. After concentrating the reaction mixture and distilling off the additives (and solvent), fractional distillation is carried out under reduced pressure or normal pressure to obtain trialkyltin halide and monoalkyltin trihalide. It is also possible to extract and separate with water by taking advantage of the philic nature of monoalkyltin trihalide. The process of the present invention produces trialkyltin halide and monoalkyltin trihalide in a molar ratio of about 1:1.

This ratio does not change even if the stannic halide is used in excess. In addition, virtually no by-product of dialkyltin dihalide was observed. Furthermore, although the raw material tetraalkyltin may contain trialkyltin halide, it does not affect the process of the present invention, but only increases the trialkyltin halide in the product by that amount. By the method of the present invention, trialkyltin halide and monoalkyltin trihalide can be produced simultaneously, and purification and separation is easy, so it is an industrially advantageous method that is not found in conventional methods. Examples will now be given to explain the method of the present invention.

Example 1 1307 (0.5 mol) of tin tetrachloride and 200 ml of benzene were charged into 11 four-bottle flasks equipped with a stirrer, a thermometer, a condenser, and a dropping funnel, and while stirring, 86.17 g of tetrahydrofuran was added from the dropping funnel. (1 mol) is added dropwise at room temperature.

Tin tetrachloride and tetrahydrofuran react immediately and generate heat, so the reaction is controlled by cooling. After the dropwise addition is completed, the mixture is heated and reacted under reflux for 30 minutes. Then, 173.6y (0,5
mol) was added dropwise over 30 minutes, and the reaction was then carried out for 1 hour.
The reaction mixture is a light brown clear solution. As a result of analyzing the product composition of this reaction mixture using gas chromatography, only peaks for monobutyltin trichloride and tributyltin chloride were observed, and only traces of unreacted tin tetrachloride, tetrabutyltin, and dibutyltin cyclolade were observed. Ta. The production ratio of monobutyltin towachloride and towabutyltin chloride was approximately 1:1 in molar ratio (46:54 in weight ratio). The reaction mixture was concentrated to remove benzene and tetrahydrofuran, and then distilled under reduced pressure to 92-94°C/10
Monobutyltin trichloride of mmH7 fraction 140.
07 (purity 99.2%) and 144-146℃/10m
Tributyltin chloride of fraction 711H7 160.9
y (purity 98.7%) was obtained. Total yield 99.1%. Examples 2 to 6 The same reaction operations as in Example 1 were carried out using the same amounts of tin tetrachloride, tetrabutyltin and benzene, but varying the amount of tetrahydrofuran added.

The results are shown in Table 1. Examples 7 to 9 In this example, 104.17 (0.3 mol) of tetrabutyltin and 200 ml of benzene were used, and the charging ratio of tin tetrachloride was changed.

The amount of tetrahydrofuran added is 2 to tin tetrachloride.
The reaction was carried out under the same conditions and operations as in Example 1 except that twice the molar amount was used. In this example, since an excess of tin tetrachloride is used, it precipitates as an adduct with tetrahydrofuran after the reaction. This precipitate was filtered out and its amount was measured. The results are shown in Table 2. Example 10 A reaction vessel was charged with 130.07 y (0.5 mol) of tin tetrachloride, and 114.2 y (1.5 mol) of methoxybutanol was added dropwise thereto over about 30 minutes at room temperature.

After that, keep it at a temperature of 100±5℃ for 30 minutes, and then
℃ and in about 1 hour, 267.8% of tetraoctyltin
7 (0.5 mol) was added dropwise. The reaction was further continued at this temperature for 1 hour. The resulting reaction mixture was concentrated and the composition of the product was examined using gas chromatography, and it was found that the weight ratio of monooctyltin trichloride and trioctyltin monochloride was 40.3:59.7 (molar ratio 1:1). exists,
Only traces of dioctyltincyclolade were observed. No peaks for tin tetrachloride or tetraoctyltin were observed. 300 ml of 10% hydrochloric acid water was added to the reaction mixture to extract monooctyltin trichloride, and the hydrochloric acid water extract layer was hydrolyzed with an aqueous caustic soda solution to obtain 130.87% monooctyltin trichloride (purity was determined by the methylation method). The analysis result was 99.1%). The organic layer was dehydrated and decolorized by adding activated clay, and the resulting solution was concentrated to obtain 236.5y of trioctyltin chloride (purity 98.7%). The total yield was almost quantitative. Example 11 A reaction vessel was charged with 130.0 y (0.5 mol) of tin tetrachloride and 200 m2 of toluene, and 88.1 y of dioxane was added thereto.
(1.0 mol) was added dropwise at room temperature over about 30 minutes.

Then, after keeping the temperature at 100±5℃ for 15 minutes,
Tetrapropyltin 145.57 (0.
5 mol) was added dropwise over 45 minutes. It was further kept at the same temperature for 15 minutes. The resulting reaction mixture was concentrated and the composition of the product was examined using gas chromatography. The production ratio of monopropyltin trichloride and tripropyltin chloride was 48.6:51.4 by weight (about a molar ratio). 1:1). Also, only traces of dipropyltin cyclolade were observed. No peaks of tin tetrachloride and tin tetrapropyl were observed. The reaction mixture was distilled to give monopropyltin trichloride 131.87 (B.p. 99~
100℃/13 Dragon Hg) and tripropyltin chloride 1
38.7y (B.p.l22~123℃/13m77H
g) was obtained.

Claims (1)

[Claims] 1 In the presence of an ether compound selected from tetrahydrofuran, dioxane, and methoxybutanol, tetraalkyltin and stannic halide are reacted to form trialkyltin halide and monoalkyltin trihalide at a ratio of approximately 1:1.
A method for producing trialkyltin halide and monoalkyltin trihalide, characterized in that they are obtained at a production ratio of (molar ratio).