JP2003212820A - Method of producing oxalyl fluorine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of efficiently and simply producing oxalyl fluoride by reaction of oxalyl chloride with an alkali metal fluoride in an aprotic solvent. <P>SOLUTION: The oxalyl fluoride is produced by carrying out the reaction between hydrofluoric acid alkali metal fluoride and oxalyl chloride in an aprotic solvent. In this case, oxalyl chloride is reacted with hydrofluoride-acidic alkali metal fluoride, after or while a mixture of the alkali metal fluoride and an aprotic solvent is treated with ultrasonic waves. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing oxalyl fluoride. More specifically, it relates to a method for producing oxalyl fluoride by reacting oxalyl chloride with an alkali metal fluoride.

[0002]

Ogizalyl fluoride is a useful substance for producing various fluorine-containing organic compounds, and is used as a starting substance for producing perfluoroalkyl vinyl ether compounds, for example. As a method for producing oxalyl fluoride, there is a method using hydrogen fluoride. In Japanese Examined Patent Publication No. 4-10462, hydrogen fluoride is contacted with oxalyl chloride in a gas phase, and in Japanese Examined Patent Publication No. 6-99357, hydrogen fluoride is added in the presence of an aliphatic tertiary amine. A method for obtaining oxalyl fluoride by reacting with oxalyl chloride is disclosed. However, hydrogen fluoride used in such a reaction has a problem that it is difficult to handle because it is a toxic substance that has a boiling point of 19.5 ° C. and turns into a gas at room temperature. There is a problem that the cost is high and the operation is complicated. Furthermore, when hydrogen fluoride is used in the presence of an aliphatic tertiary amine, a tertiary amine-hydrogen fluoride complex solution has to be prepared, and there is a problem that the process becomes complicated.

In order to solve such a problem, a method using an alkali metal fluoride has been proposed. Japanese Patent Examination 6-9935
In No. 8 publication, it is reported that oxalyl chloride can be obtained in good yield by reacting oxalyl chloride in an aprotic polar solvent using a fine particle alkali metal fluoride having a particle size of 10 μm or less. Since the fine particle alkali metal fluoride used in the method needs to be 10 μm or less, there is a problem in that complicated work such as pulverization of particles is involved. Further, in Patent No. 2,856,849, by using sulfolane as a solvent, it is possible to use an alkali metal fluoride of 15 ~ 100 (mu) m, has solved the above problems, sulfolane has a freezing point of 28 ℃. Since reaction at room temperature is impossible, there is a problem that solidification occurs unless the reaction temperature is maintained at 28 ° C or higher. There is also a method of mixing a solvent such as tetraglyme with sulfolane, but in this case, there is a problem in that the sulfolane must be heated once to be dissolved and then mixed with another solvent.

[0004]

The object of the present invention is to produce oxalyl fluoride in the production of oxalyl fluoride by reacting oxalyl chloride with an alkali metal fluoride in an aprotic solvent. It is to provide a method of manufacturing well and simply.

[0005]

The object of the present invention is as follows.
This is achieved by a method of producing oxalyl fluoride by reacting an alkali metal fluoride fluoride with oxalyl chloride in an aprotic solvent. At this time, it is also possible to react with oxalyl chloride after or after ultrasonic treatment of a mixture of a hydrogen fluoride acidic alkali metal fluoride and an aprotic solvent.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION As an alkali metal fluoride,
Sodium fluoride, potassium fluoride, cesium fluoride,
Rubidium fluoride or the like can be used, and sodium fluoride that has low water absorption, is inexpensive, and is easily available industrially is preferably used.

Hydrogen fluoride acidic alkali metal fluoride is
Usually, it can be obtained by adsorbing or mixing hydrogen fluoride with these alkali metal fluorides. These hydrogen fluoride complexes are industrially available, and sodium hydrogen fluoride acid fluoride is preferably used because it has low water absorption, is inexpensive, and is easily available industrially. Hydrogen fluoride is used in a molar ratio of 0.1 to 1.5 times, preferably 0.2 to 1.0 times that of the alkali metal fluoride. The molar ratio of this alkali metal and hydrogen fluoride is calculated by mixing a calculated amount of metal fluoride with a hydrogen fluoride acidic alkali metal fluoride prepared in advance or adsorbing a calculated amount of hydrogen fluoride to the alkali metal fluoride or Adjusted by mixing.

The water content of the hydrogen fluoride acidic alkali metal fluoride is 2000 ppm or less, preferably 1000 ppm or less. If a water content of more than this is used, it reacts with oxalyl chloride as a raw material and oxalyl fluoride as a product to cause a decrease in yield.
Drying of the hydrogen fluoride acidic alkali metal fluoride is carried out by heating at a temperature below its decomposition temperature, preferably at about 100 to 200 ° C. for several hours. Further, it is preferable to reduce the pressure with a vacuum pump and dry.

Regarding the particle size of the hydrofluoric acid alkali metal fluoride used, the smaller the particle size, the more advantageous it is, but there is no particular restriction on the particle size, and a large particle size which is industrially readily available. The shape can be used. Examples of commercially available products include Wako Pure Chemical Industries, Ltd. first-grade reagents.

As an aprotic solvent, diglyme
(Diethylene glycol dimethyl ether), triglyme (triethylene glycol dimethyl ether), tetraglyme (tetraethylene glycol dimethyl ether), acetonitrile, adiponitrile and the like are used,
It is preferable to use triglyme, tetraglyme or the like which has a high boiling point and a low freezing point and thus does not cause the solvent to evaporate when the oxalyl fluoride is recovered and does not coagulate during the reaction. Although the reaction will proceed even if a solvent such as sulfolane is used, the freezing point is high as described above,
The reaction temperature must be maintained above 28 ° C.

The water content of the solvent is 1000 ppm or less, preferably 200 ppm or less. Also in this case, when the water content is more than that, it reacts with oxalyl chloride as a raw material and oxalyl fluoride as a product to cause a problem such as a decrease in yield. The amount of the solvent used is sufficient if it is added in such an amount that the stirring state can be maintained well when the hydrogen fluoride acidic alkali metal fluoride is dispersed in the solvent and used as a slurry. The compound is used in a weight ratio of 0.5 to 10 times, preferably 0.5 to 5 times.

The reaction of hydrogen fluoride acidic alkali metal fluoride with oxalyl chloride is carried out using oxalyl chloride.
It is used in a proportion of 1.0 to 5.0 times equivalent, preferably 1.2 to 1.7 times equivalent, in terms of F anion in the alkali metal hydrogen fluoride, relative to the COCl group of ClCOCOCl.

The reaction temperature is 0 to 60 ° C, preferably 0 to 30 ° C
Since it is at room temperature, there is no need for heating equipment or the like, and there is an advantage that oxalyl fluoride does not evaporate or decompose at high temperature.

The ultrasonic treatment is carried out by activating the particle surface of the alkali metal fluoride fluoride with an ultrasonic cleaner, for example, an ultrasonic cleaner, thereby reducing the amount of the alkali metal fluoride fluoride used. , The reaction speed can be increased. As the ultrasonic cleaner, any of those generally used can be used.

The ultrasonic treatment is applied in a mode of reacting with oxalyl chloride after or while ultrasonically treating a mixture of a hydrogen fluoride acidic alkali metal fluoride and an aprotic solvent. When the reaction is carried out while sonicating, it is not necessary to sonicate for the entire reaction time, and it may be only for the first fixed time.

The pressure during the reaction includes reduced pressure, atmospheric pressure,
It is possible to synthesize under pressure, but it is preferable to synthesize under atmospheric pressure in consideration of the cost of equipment and the like.

The recovery of oxalyl fluoride is separated by distillation under reduced pressure, pressurization and atmospheric pressure. Since oxalyl fluoride decomposes by heating, it is preferably separated under reduced pressure.

[0018]

EFFECTS OF THE INVENTION By the method for producing oxalyl fluoride according to the present invention, oxalyl chloride and hydrofluoric acid alkali metal fluoride can be reacted to easily produce oxalyl fluoride in good yield. it can. Further, during this reaction, ultrasonic treatment is performed to activate the particle surfaces of the hydrogen fluoride acidic alkali metal fluorides, thereby reducing the amount of the hydrogen fluoride acidic alkali metal fluorides used and increasing the reaction rate. Can be raised.

[0019]

EXAMPLES Next, the present invention will be explained with reference to examples, but the present invention is not limited to these.

Example 1 A 5 L flask equipped with a reflux condenser cooled to -5 to -10 ° C. and a stirrer was placed in a flask having a hydrogen fluoride mixture molar ratio of 1.0 (HF / fluoride). Sodium (first-class reagent of Wako Pure Chemical Industries) 930 g (O
(1.5 times equivalent of OCl) and 930 g of tetraglyme dried with molecular sieves were charged. While stirring at room temperature, 1270 g of oxalyl chloride was added over 3 hours. The reaction liquid 1 hour after the end of the addition is analyzed by a gas chromatograph,
When the conversion rate was measured, it was found to be 100% conversion. Therefore, oxalyl fluoride was evaporated from the solvent under reduced pressure and collected in a dry ice-methanol cold trap. As a result of analysis by infrared absorption spectrum, it was confirmed to be oxalyl fluoride, and the yield was 95%.

Example 2 In a flask having a capacity of 300 mL equipped with a reflux condenser cooled to -5 to -10 ° C and a stirrer, hydrogen fluoride acidic fluorinated with a hydrogen fluoride mixing molar ratio of 1.0 (HF / fluoride). 59 g of potassium (1.5 equivalents of oxalyl chloride COCl in terms of F anion) and 50 g of tetraglyme dried with molecular sieves were charged. 64 g of oxalyl chloride while stirring at room temperature
Added over time. After 1 hour from the end of the addition, the reaction solution was analyzed by gas chromatography and the conversion was measured.
Since 0% conversion had occurred, oxalyl fluoride was evaporated from the solvent under reduced pressure and collected in a dry ice-methanol cold trap. As a result of analysis by infrared absorption spectrum, it was confirmed to be oxalyl fluoride, and the yield was 93%.

Example 3 The same operation as in Example 1 was carried out by using 129 g of cesium hydrogen fluoride acid fluoride (HF / fluoride molar ratio: 1.0) in place of sodium hydrogen fluoride acid fluoride. ,
The results were 100% conversion and 92% yield.

Example 4 The same operation as in Example 1 was carried out by using 48 g of triglyme instead of tetraglyme, and the conversion rate was 100.
%, Yield 95% was obtained.

Example 5 The same operation as in Example 1 was carried out by using 38 g of acetonitrile instead of tetraglyme, and the conversion was 1
The result was 00% and the yield was 93%.

Example 6 The same operation as in Example 1 was carried out by using 56 g of sodium hydrogen fluoride acid fluoride having an HF molar ratio (HF / fluoride) of 0.25. The conversion was 100% and the yield was 100%. The result of 92% was obtained.

Example 7 The same operation as in Example 1 was carried out using 51 g of sodium hydrogen fluoride hydrofluoride having an HF molar ratio of 0.55, and the results were a conversion of 99% and a yield of 88%. Was given.

Example 8 The same operation as in Example 2 was carried out using 76 g of potassium hydrogen fluoride acid fluoride having an HF molar ratio of 0.25, and the results were that the conversion rate was 100% and the yield was 90%. Was obtained.

Example 9 In a flask having a volume of 5 L equipped with a reflux condenser cooled to -5 to -10 ° C and a stirrer, 806 g of sodium hydrogen fluoride acid fluoride having a hydrogen fluoride mixing molar ratio of 1.0 (F anion conversion) Then, 1.3 g equivalent of oxalyl chloride COCl) and 806 g of tetraglyme dried with molecular sieves were charged. Under stirring conditions,
After ultrasonic treatment for 30 minutes using an ultrasonic cleaner (UT-204 manufactured by Sharp), 1270 g of oxalyl chloride was added over 3 hours with stirring at room temperature. After 1 hour from the end of the addition, the reaction mixture was analyzed by gas chromatography and the conversion was measured.As a result, it was found that 100% conversion had occurred, so oxalyl fluoride was evaporated from the solvent under reduced pressure, and dry ice-methanol cold trap was used. Collected in. As a result of analysis by infrared absorption spectrum, it was confirmed to be oxalyl fluoride, and the yield was 96%.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuhiro Yamamoto             831-2 Kamiaida, Isohara-cho, Kitaibaraki-shi, Ibaraki             Inside Mectron Co., Ltd. F-term (reference) 4H006 AA02 AC47 BA91 BB41 BE01                       BE61 BM71 BS90

Claims (4)

[Claims] 1. A method for producing oxalyl fluoride, which comprises reacting an alkali metal fluoride fluoride with oxalyl chloride in an aprotic solvent. 2. A method for producing oxalyl fluoride, which comprises sonicating a mixture of a hydrogen fluoride acidic alkali metal fluoride and an aprotic solvent and then reacting the mixture with oxalyl chloride. 3. A method for producing oxalyl fluoride, which comprises reacting with oxalyl chloride while sonicating a mixture of a hydrogen fluoride acidic alkali metal fluoride and an aprotic solvent. 4. The method for producing oxalyl fluoride according to claim 1, 2 or 3, wherein the aprotic solvent is diglyme, triglyme, tetraglyme, acetonitrile or adiponitrile.