JPH0251896B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a novel perfluorocarboxylic acid fluoride and a method for producing the same. More specifically, the present invention provides, for example, surfactants,
The present invention relates to perfluoro(3-dialkylamino-n-butyric acid fluoride) useful as a synthetic intermediate for fluorine-containing products such as agricultural chemicals and pharmaceuticals, and fluorine-containing polymeric monomers, and a method thereof. PRIOR ART Certain perfluorocarboxylic acid fluorides are known and used, for example, as surfactants, lubricants, water repellents and
It is known that it can be used as a raw material for oil repellents, monomers for producing polymeric compounds, etc. These known perfluorocarboxylic acid fluorides are mainly produced by electrolytic fluorination, but other methods include the reaction of perfluoroalkyl iodide with SO ₃ or ClSO ₃ H (French Patent No. 1343661). U.S. Patent No.
3238240), oxidation reaction of perfluoroalkylvinylidene chloride (Japanese Patent Application Laid-open No. 188345/1983)
Other methods are also known. However, perfluorocarboxylic acid fluoride containing a nitrogen atom as a heteroatom in the molecule is slightly perfluoro(N,N-dimethylglycine fluoride) [Journal of American Chemical Society (J.
Amer.Chem.Soc.) Volume 80, Page 1889 (1959)], perfluoro(β-alkylaminopropionyl fluoride (U.S. Pat. No. 3,471,484)), perfluoro(α-alkylaminopropionyl fluoride) (Unexamined Japanese Patent Publication No. 103042/1983,
60-166888) is known, the selection range of perfluorocarboxylic acid fluoride according to various purposes of use is inevitably limited. Problems to be Solved by the Invention An object of the present invention is to provide a new perfluoro(3-dialkylamino-n-butyric acid fluoride) suitable as an intermediate for surfactants, agricultural chemicals, pharmaceuticals, etc. The objective is to further expand the range of raw materials available for various products. Means for Solving the Problems As a result of intensive research in order to develop a new perfluorocarboxylic acid fluoride, the present inventors discovered that a reactive derivative of 3-dialkylamino-n-butyric acid was dissolved in liquid hydrogen fluoride. When electrolytically fluorinated in 1, the corresponding new perfluoro(3-dialkylamino-n-butyric acid fluoride) can be obtained in a relatively good yield, and this product can be used for the same applications as conventional perfluorocarboxylic acid fluoride. Based on this knowledge, the present invention was completed. That is, the present invention provides the general formula (R ₁ and R ₂ in the formula are each a perfluoroalkyl group having 1 to 5 carbon atoms, and both are bonded directly or through an oxygen atom or a nitrogen atom, and together with the nitrogen atom to which they are bonded, five perfluoro(3-dialkylamino-n-butyric acid fluoride) represented by Accordingly, the general formula (R ₁ ′ and R ₂ ′ in the formula are each an alkyl group having 1 to 5 carbon atoms, and both are bonded directly or through an oxygen atom or a nitrogen atom, and together with the nitrogen atom to which both are bonded, A reactive derivative of 3-dialkylamino-n-butyric acid represented by be able to. The present invention will be explained in detail below. The perfluoro(3-dialkylamino-n-butyric acid fluoride) of the present invention represented by the above general formula (

As an example of [formula]),

【formula】

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【formula】

[Formula] (where n and m are integers of 1 to 5). In the present invention, perfluoro(3-dialkylamino-n-
As a raw material for butyric acid fluoride), 3-dialkylamino-n- represented by the general formula ()
Reactive derivatives of butyric acid are used. Examples of the reactive derivatives include acid halides, lower alkyl esters, acid anhydrides, unsubstituted or N-mono,
Examples include dialkyl-substituted acid amides. Among these reactive derivatives, 3-(N,N-dialkylamino)-
N-butyric acid methyl ester is preferred. This 3-
(N,N-dialkylamino)-n-butyric acid methyl ester can be prepared, for example, by the method of Perring [J.Org.Chem., Vol. 18, p. 901 (1933).
It can be obtained in high yield by addition-reacting the corresponding dialkylamine or cyclic amine with methyl crotonate according to [2013]. In the electrolytic fluorination reaction in the present invention,
An electrolytic cell commonly used in conventional electrolytic fluorination reactions can be used. In addition, the reaction is carried out in liquid hydrogen fluoride, and in this case, the concentration of the reactive derivative of the starting material 3-dialkylamino-n-butyric acid is not practical if it is too low, and tar-like substances are generated if it is too high. Since it is easy to use, it is usually selected in the range of 1 to 80% by weight, preferably 3 to 20% by weight. The current density is usually 0.01 to 10 A/dm ² , preferably 0.1 to 5 A/dm ²
selected within the range. If this current density is too high, the electrolysis voltage will become too high and side reactions will easily occur. Furthermore, if the electrolysis temperature is too low, the electrolysis voltage will become too high, while if it is too high, hydrogen fluoride will easily escape, so it is usually selected in the range of -20 to 50℃, preferably -10 to 20℃. . This electrolytic reaction is usually carried out at normal pressure, but can also be carried out under increased pressure if desired. When the reaction is carried out under pressure, the boiling point of hydrogen fluoride increases, so there is an advantage that cooling of the reaction system can be eased. Moreover, either a continuous method or a batch method can be used to carry out the reaction. When this is carried out in batches, the electrolysis time to complete the reaction depends on the current density and the amount of raw materials, but generally the amount of electricity is 80 to 200% of the theoretical amount of electricity.
It is preferable to adjust the range so that Since these electrolytic fluorination conditions differ depending on the type of raw material used, they are preferably selected appropriately taking into account the yield of the desired product, current efficiency, etc.
In addition, in order to perform electrolytic fluorination efficiently and improve the yield of the target product, it is desirable to stir the electrolyte during the reaction. Methods such as the following can be used. Perfluoro(3-dialkylamino-n-butyric acid fluoride) thus obtained has a relatively low boiling point (approximately 40 to 100°C).
degree), it may come out of the electrolytic cell together with the gas produced during electrolysis. In such a case, the produced gas can be passed through, for example, a layer of pellets of sodium fluoride to remove hydrogen fluoride, and then the desired product can be collected in a cooling trap.
In addition, the perfluoro(3-dialkylamino-
n-butyric acid fluoride) has a high boiling point (approximately
100°C or higher), most of it remains in the electrolytic cell and does not dissolve in liquid hydrogen fluoride, but separates to form two layers, so it can be drained and taken out after electrolysis is complete. Through such electrolytic fluorination reaction, 3-dialkylamino-n represented by the general formula ()
- From reactive derivatives of butyric acid, perfluoro(3-dialkylamino-n-butyric acid fluoride) usually represented by the corresponding general formula ()
is obtained. That is, in the general formula ()
R ₁ ′ and R ₂ ′ usually change to R ₁ and R ₂ in the corresponding general formula () as shown below. (n and m in the formula have the same meanings as above) In this way, a nitrogen-containing perfluorocarboxylic acid fluoride having a perfluoroalkyl group corresponding to the alkyl group of the starting compound is obtained. Effects of the Invention According to the present invention, novel perfluoro(3-dialkylamino-n-butyric acid) can be produced in good yield by electrolytically fluorinating a reactive derivative of 3-dialkylamino-n-butyric acid that is easily available. fluoride) is obtained. This product is useful, for example, as a synthetic intermediate for fluorine-containing products such as surfactants, agricultural chemicals, and pharmaceuticals, and monomers for fluorine-containing polymer compounds. Examples Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples in any way. The electrolytic cell used was made of Monel metal, and the electrodes used were 7 anodes and 8 cathodes made of nickel plates arranged alternately with a distance of 2 mm, with an effective anode area of 7.5 dm ^2. did. Example 1 450 ml of anhydrous hydrofluoric acid was introduced into an electrolytic cell, and trace amounts of impurities were removed by preliminary electrolysis. then 3
-(N,N-dimethylamino)-n-butyric acid methyl ester 40.9g was added to the electrolytic cell, and the anode current density was
3.3A/dm ² , bath temperature 7~9℃, electrolysis voltage 6.1~6.2V
263Ahr electrolysis was carried out. The electrolytic voltage is finally
It reached 7.1V. The generated gas was passed through a sodium fluoride tube to remove accompanying hydrogen fluoride, and then collected in a trap cooled to -78°C, yielding 33.6 g of a fluorocarbon mixture. After electrolysis, the drain tank at the bottom of the electrolytic cell was opened and 18.7 g of high boiling point fluorocarbon was extracted as a cell drain compound. Next, a small amount of pellet-like molecular sieve 4A was added to these to remove the remaining hydrogen fluoride, and then gas chromatography [carrier: He, liquid phase: 1,6-bis(1,1,12 −
trihydroperfluorododecyloxy)hexane, carrier: 60-80 methoxychromosorb PAW],
Analysis by IR, ¹⁹ FNMR, Mass, elemental analysis (carbon), etc. revealed that perfluoro[3-(N,
N-dimethylamino)-n-butyric acid fluoride]
16.6g (yield 16.9 mol%, all percentages below are mol%)
) obtained. At this time, a small amount of perfluoro[3-(N,N-dimethylamino)oxolane] was also produced as a cyclized product. The perfluoro[3-(N,N-dimethyl)-
n-butyric acid fluoride] is a new compound, and its physical properties as a methyl ester are boiling point 125-126℃, n ²⁰ _D
1.3067, d ²⁰ ₄ 1.6843, and its infrared absorption spectrum characteristic absorption is

The absorption based on [Formula] is at ν _c=p 1788cm ^-1 . Example 2 The same conditions and method as in Example 1 were used, except that 40.6 g of 3-(diethylamino)-n-butyric acid methyl ester was used and electrolysis was performed for 249 Ahr at an electrolytic voltage of 6.6 to 6.7 V until it reached 8.4 V. Electrolytic fluorination was performed. After the electrolysis was completed, the drain tank at the bottom of the electrolytic cell was opened to obtain 23.6 g of a fluorocarbon mixture. Also, during the cooling trap, fluorocarbon mixtures
24.8g was collected. When these were treated and analyzed in the same manner as in Example 1, it was found that perfluoro[3]
-(diethylamino)-n-butyric acid fluoride〕5.2
g (yield 4.7%) was obtained. Perfluoro[3-(diethylamino)-n-butyric acid fluoride] is a new compound, and its physical properties as a methyl ester are boiling point 159-160℃, n ²⁰ _D 1.3142,
d ²⁰ ₄ 1.7508, and its infrared absorption spectrum characteristic absorption is

Absorption based on [Formula] ν _c=p 1788cm ^-1 . Example 3 3-(pyrrolidino)-n-butyric acid methyl ester
Example 1 except that 40.3g was used and electrolysis was performed for 221Ahr at an electrolysis voltage of 6.4 to 6.5V until reaching 7.0V.
Electrolytic fluorination was carried out under the same conditions and method.
After electrolysis, 45.1 g of cell drain compound and 13.0 g of fluorocarbon mixture were obtained in the cooling trap. When these were treated and analyzed in the same manner as in Example 1, 20.5 g of perfluoro[3-(pyrrolidino)-n-butyric acid fluoride] (yield
21.2%) obtained. At this time, a small amount of perfluoro[3-(pyrrolidino)oxolane] was also produced as a cyclization product. Perfluoro[3-(pyrrolidino)-n-butyric acid fluoride] is a new compound, and its physical properties as a methyl ester are boiling point 151-153℃, n ²⁰ _D 1.3220, d ²⁰ _D
1.7444, and its infrared absorption spectrum characteristic absorption is

The absorption based on [Formula] is at ν _c=p 1788cm ^-1 . Example 4 3-(morpholino)-n-butyric acid methyl ester
Example 1 except that 40.7g was used and electrolysis was performed for 228Ahr at an electrolysis voltage of 5.9 to 6.1V until reaching 7.0V.
Electrolytic fluorination was carried out under the same conditions and method.
After electrolysis, 34.1 g of the fluorocarbon mixture was obtained as cell drain compound and 12.6 g as agglomerate in the cooling trap. When these were treated and analyzed in the same manner as in Example 1, perfluoro[3-(morpholino)-n-butyric acid fluoride] was detected.
12.6g (yield 13.5%) was obtained. In addition, a small amount of perfluoro[3-(morpholino)oxolane] was also obtained as a cyclized product. Perfluoro[3-(morpholino)-n-butyric acid fluoride] is a new compound, and its physical properties as a methyl ester are boiling point 160-163℃, n ²⁰ _D 1.3248,
d ²⁰ ₄ 1.7671, and its infrared absorption spectrum characteristic absorption is

The absorption based on [Formula] is at ν _c=p 1793cm ^-1 . Example 5 3-(piperidino)-n-butyric acid methyl ester
Example 1 except that 40.3g was used and electrolysis was performed for 243Ahr at an electrolysis voltage of 6.1 to 6.3V until reaching 6.5V.
Electrolytic fluorination was carried out under the same conditions and method.
After electrolysis, 50.8 g of the fluorocarbon mixture was obtained as cell drain compound and 8.6 g as agglomerate in the cooling trap. When these were treated and analyzed in the same manner as in Example 1, it was found that perfluoro[3]
-(piperidino)-n-butyric acid fluoride) is 21.1g
(yield 21.0%). At the same time, perfluoro[3-(piperidino)] is also used as a cyclization product.
A small amount of oxolane] was also obtained. Perfluoro[3-(piperidino)-n-butyric acid fluoride] is a new compound, and its physical properties as a methyl ester are boiling point 167-168℃, n ²⁰ _D 1.3271,
d ²⁰ ₄ 1.7958, and its infrared absorption spectrum characteristic absorption is

The absorption based on [Formula] is at ν _c=p 1788cm ^-1 . Example 6 Using 40.5 g of 3-(hexamethyleneimino)-n-butyric acid methyl ester, the electrolytic voltage was 6.5 to 6.6 V.
Except for 243Ahr electrolysis until reaching 8.0V,
Electrolytic fluorination was carried out under the same conditions and method as in Example 1. After electrolysis, 55.2 as a cell drain compound
g, and 8.2 g of fluorocarbon mixture as agglomerate in the cooling trap. When these were processed and analyzed in the same manner as in Example 1, the target product perfluoro[3-(hexamethyleneimino)-n
-Butyric acid fluoride] 12.9 g (yield 12.4%) and ring-isomerized perfluoro[3-(methylpiperidino)-n-butyric acid fluoride] 15.3 g (yield 14.7%) were obtained. Perfluoro[3-(hexamethyleneimino)-
n-butyric acid fluoride] is a new compound, and its physical properties as a methyl ester include a boiling point of 186-188℃;
n ²⁰ _D 1.3332, d ²⁰ ₄ 1.8162, and its infrared absorption spectrum characteristic absorption is

The absorption based on [Formula] is at ν _c=p 1791cm ^-1 .

Claims (1)

[Claims] 1. General formula (R ₁ and R ₂ in the formula are each a perfluoroalkyl group having 1 to 5 carbon atoms, and both are bonded directly or through an oxygen atom or a nitrogen atom, and together with the nitrogen atom to which they are bonded, five perfluoro(3-dialkylamino-n-butyric acid fluoride), which may form a heterocyclic ring, a six-membered ring, or a seven-membered ring. 2 General formula (R ₁ ′ and R ₂ ′ in the formula are each an alkyl group having 1 to 5 carbon atoms, and both are bonded directly or through an oxygen atom or a nitrogen atom, and together with the nitrogen atom to which both are bonded, It is characterized by electrolytically treating a reactive derivative of 3-dialkylamino-n-butyric acid represented by , general formula (R ₁ and R ₂ in the formula are each a perfluoroalkyl group having 1 to 5 carbon atoms, and both are bonded directly or through an oxygen atom or a nitrogen atom, and together with the nitrogen atom to which they are bonded, five A method for producing perfluoro(3-dialkylamino-n-butyric acid fluoride), which may form a heterocyclic ring, a six-membered ring, or a seven-membered ring.