JPH0415215B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a novel method for producing perfluoroolefins containing di-substituted amino groups.
More specifically, the present invention is useful as a synthetic intermediate for fluorine-containing products such as surfactants, dyes, agricultural chemicals, pharmaceuticals, and optically active analytical reagents, and as a monomer for producing fluorine-containing polymeric compounds. The present invention relates to a method for easily and efficiently producing perfluoroolefins. Background Art In recent years, fluorine-containing olefin compounds have been in the spotlight as synthetic intermediates and raw materials for various fluorine-containing products. It is widely used as a monomer for producing fluorine polymer compounds. By the way, since perfluoroolefins having a perfluoro(N,N-dialkyl)amino group have a double bond as a reactive site,
By using this compound as an intermediate raw material, it is possible to produce various useful compounds having the perfluoro(N,N-dialkylamino) group. In addition, the perfluoroolefins can be copolymerized with other fluoroolefins to form perfluoro(N,N-dialkylamino) in the polymer.
By introducing a group, it becomes possible to reduce the crystallinity and improve the mechanical properties of the polymer. However, as such perfluoroolefins, perfluoro(N,
N-dimethylvinylamine) (U.S. Patent No. 3311599)
Specification), perfluoro(N-vinylpyrrolidine) (Japanese Patent Application No. 162632/1982), perfluoro(N-vinylpyrrolidine)
Vinylmorpholine) [J.Chem.Soc., Journal of Chemical Society,
Perkin I), page 5 (1973)], perfluoro(N-vinylpiperidine) [J.Chem.Soc., (C)]
No. 2608 (1968)], perfluoro(N-vinylamine) and perfluoro[3-
(N,N-dimethylamino)-2-propene] [Journal of Chemical Society (J.
Chem.Soc., Perkin I)” page 1633 (1975
)] are known. Among these, perfluoro[3-(N,N,
N-dimethylamino)-2-propene] is obtained by first converting N-bromobistrifluoromethylamine into
A 1:1 adduct is synthesized by a radical addition reaction with 1H-pentafluoropropene-1, and then an unsaturated bond is formed by dehydrobrominating the obtained 1:1 adduct. It is synthesized through a two-step reaction. That is, as (CF ₃ ) ₂ NBr＋cis/transCF ₃ CF=CHFhν --→ (CF ₃ ) ₂ NCHFCFBrCF ₃ , (CF ₃ ) ₂ CH ₂ CFBrCF ₃ , CF ₃ CFBrCHFBr, (CF ₃ ) ₂ NN(CF ₃ ) ₂ as threo(CF ₃ ) ₂ NCHFCFBrCF ₃ KOH ――――――→ cis(CF ₃ ) ₂ NCF=CFCF ₃ yield=78% erythro(CF ₃ ) ₂ NCHFCFBrCF ₃ KOH ――――――→ cis/ trans (CF ₃ ) ₂ NCF = CFCF ₃ Yield = 100% (cis/trans = 38:62) However, this method first and foremost synthesizes a terminal olefin (CF ₃ ) ₂ NCF ₂ CF = CF ₂ Furthermore, the synthesis of the raw materials (CF ₃ ) ₂ NBr and CF ₃ CF ₂ =CHF requires a complicated and multi-step process, and the two-step reaction described above is required. This has the drawback that the operation is complicated. Additionally, other types of perfluoroalkenylamines

Even if this method is applied to the synthesis of [Formula], perfluoroalkylamino radical donor (

[Formula] Br or F) is difficult to synthesize and is generally difficult to use. As such, only limited types of perfluoro(disubstituted amino-alkenes) have been obtained as nitrogen-containing olefins, so the scope of their use is subject to significant control. The emergence of certain perfluorinated compounds has been desired. Problems to be Solved by the Invention Under these circumstances, the present invention provides a tertiary amino group useful as a synthetic intermediate for various fluorine-containing compounds or as a monomer for fluorine-containing polymeric compounds. The purpose of this invention is to provide an industrial method that can produce perfluoroolefins having the following from readily available raw materials with a high yield through simple processing. Means for Solving the Problems In order to develop an industrial method for producing such perfluoroolefins, the present inventors have conducted extensive research and found that the raw material has a perfluoro-tertiary amino group at the 3-position. Perfluoro(isobutyric acid)
It has been discovered that perfluoroalkenylamines can be obtained surprisingly easily by using acid fluorides, perfluoroalkyl esters, or salts of these materials and heat-treating them at specific temperatures.Based on this knowledge, the present invention has been completed. It came to this. That is, the present invention provides the general formula [In the formula, R ₁ and R ₂ 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, It may form a heterocyclic ring, a six-membered ring, or a seven-membered ring, and X is a fluorine atom, a perfluoroalkoxy group, or a -
OM (where M is a monovalent alkali metal or alkaline earth metal)] is characterized by heat-treating a perfluoro(3-disubstituted isobutyric acid) derivative at a temperature of 100 to 500°C. The general formula (C ₃ F ₅ in the formula is a 1-perfluoropropenyl group or a 2-perfluoropropenyl group, R ₁ and R ₂
has the same meaning as above) This provides a method for producing perfluoro(3-disubstituted aminopropene). The present invention will be explained in detail below. In the compound represented by the general formula () of the present invention,

As an example of [formula],

【formula】

【formula】

【formula】

【formula】

【formula】

【formula】

【formula】

【formula】

【formula】

【formula】

[Formula] (n and m in the formula are integers of 1 to 5). In the present invention, in order to produce these compounds, a perfluoro(3-disubstituted aminoisobutyric acid) derivative represented by the above general formula () is used as a raw material. This one is, for example, the general formula (R ₃ and R ₄ 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 they are bonded, they are five-membered. A reactive derivative of 3-disubstituted aminoisobutyric acid represented by By doing so, it can be easily manufactured. In this case, for example, if methyl ester is used as a raw material, a small amount of perfluoro (methyl 3-disubstituted isobutyrate) will be produced along with perfluoro (3-disubstituted aminoisobutyric acid fluoride), but this can also be used as a raw material. There is no need to separate them because it can be done. In addition, perfluoro(3-disubstituted aminoisobutyric acid) salts can be prepared by adding an alkali metal or alkali to perfluoro(3-disubstituted aminoisobutyric acid fluoride) and perfluoro(methyl 3-disubstituted aminoisobutyrate) obtained as described above. It can be produced by reacting earth metal hydroxides. In the present invention, perfluoro(3-disubstituted aminoisobutyric acid) represented by the general formula ()
The perfluoro(3-disubstituted aminopropene) represented by the above general formula () can be easily produced by simply heat-treating the derivative at a temperature in the range of 100 to 500°C. On this occasion,
It is advantageous to use perfluoro(3-disubstituted aminoisobutyric acid fluoride), perfluoro(sodium 3-disubstituted aminoisobutyrate), and perfluoro(potassium 3-disubstituted aminoisobutyrate) as raw materials because thermal decomposition proceeds easily. It is. The thermal decomposition reaction temperature is 100-500℃, preferably
It is necessary to choose a temperature within the range of 200 to 300℃. This temperature
Below 100℃, the conversion rate is too low to be practical;
If the temperature exceeds 500°C, undesirable side reactions such as decomposition are likely to occur. Further, the reaction time depends on the treatment temperature, but is usually within the range of 10 seconds to 2 hours. When the treatment temperature is high, the reaction time becomes short, whereas when the treatment temperature is low, the reaction time becomes long, so it is desirable to adopt appropriate conditions as appropriate. In this thermal decomposition reaction, the reaction pressure is not an important factor, and the reaction can be carried out under reduced pressure, atmospheric pressure, or increased pressure.
It is preferable to carry out the reaction under atmospheric pressure or reduced pressure because it is relatively easy to recover the reaction product. Depending on the reaction form, the thermal decomposition reaction can be carried out using inert gases such as nitrogen, helium, argon, carbon dioxide, polyethers, tetrachloroethylene, n
- It may also be carried out using an aprotic liquid compound such as heptane as a diluent. In this case, the dilution ratio is preferably 100 times or less. In the method of the present invention, when perfluoro (3-disubstituted aminoisobutyric acid fluoride) is used as a raw material, it is preferable to carry out the thermal decomposition reaction in the presence of a metal salt or metal oxide. In this case, the perfluoro(3 -disubstituted aminopropenes) are obtained as a mixture. There are no particular restrictions on the material of the pyrolysis reactor, but stainless steel or Hastelloy is usually used. Furthermore, there are no particular restrictions on the format of the filling layer;
Any type of bed, such as a fixed bed, moving bed, or fluidized bed, can be used. Examples of the metal salt include sodium carbonate,
Potassium carbonate, lithium carbonate, sodium phosphate, potassium phosphate, barium carbonate, calcium carbonate, magnesium carbonate, potassium sulfate, sodium sulfate, etc.; examples of metal oxides include zinc oxide, cadmium oxide, etc.; Solid bases such as sodium carbonate and potassium carbonate are toxic substances generated in thermal decomposition reactions.
It is particularly suitable because it can decompose COF ₂ . Also,
In this case, perfluoroalkylcarbanion is thought to be produced as a reaction intermediate in this thermal decomposition reaction.

The perfluoroolefin produced by selecting a carbonate of an alkali metal (for example, K ⁺ >Na ⁺ ) that can be more stable for [Formula] is a perfluoro(3-disubstituted amino-2 -propene) is obtained as product. Effects of the Invention According to the method of the present invention, perfluoro(3-disubstituted-2-propene) and perfluoro(3-disubstituted amino-2-propene) can be produced in high yield from easily available raw materials through an extremely simple process. This method is useful as an industrial method for producing these compounds. In addition, the perfluoro(3-disubstituted aminopropene) has extremely high industrial value as a synthetic intermediate or polymer monomer for fluorine-containing products such as surfactants, agricultural chemicals, pharmaceuticals, and optically active analytical reagents. It is. For example, perfluoro(3-disubstituted amino-2
-propene) can be easily derived into perfluorocarboxylic acid as shown in the reaction formula below, and this acid has an asymmetric carbon atom and can be used as an optically active substance that can be used to measure the optical purity of amines. , are useful as intermediates for the synthesis of such final substances. Furthermore, substances with bulky groups tend to have better performance as optically active substances,
From this point of view as well, the bulky compound of the present invention can provide higher performance as a synthetic intermediate for producing optically active substances. Additionally, perfluoro(3-disubstituted amino-1-
Propene) can be easily isomerized to perfluoro (3-disubstituted amino-2-propene) with a catalyst (fluorine ion) and can therefore be used in the same manner. 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. Example 1 A flash evaporator for vaporizing raw materials and a diluent gas flow rate control device were connected to the inlet side, and the outlet side was equipped with a low-temperature trap for condensing and collecting reaction products.Length 48.0 cm A stainless steel tube with an inner diameter of 2.5 cm was used as a horizontal pyrolysis reactor. Fill this with 87.6 g of powdered anhydrous sodium carbonate horizontally to almost the middle of the reactor, fill both ends with metal wool, and let helium gas flow at a rate of 100 ml/min for about 2 hours.
The temperature was kept at 300°C to dry the sodium carbonate. As a raw material, a product obtained by electrolytically fluorinating 3-dimethylaminoisobutyric acid methyl ester (celdrain compound) was used as it was. The product contains 84.4% by weight of perfluoro(3-dimethylaminoisobutyric acid fluoride) and perfluoro(methyl 3-dimethylaminoisobutyrate), respectively.
It contained 7.8% by weight. First, the reactor was kept at 220°C, helium gas was allowed to flow at 100 ml/min, and 5.03 g of the fluorocarbon mixture was poured into the reactor at 40° C. using a micro-metering pump.
The mixture was fed to an instantaneous evaporator for a few minutes, vaporized and mixed with helium gas which was quantitatively fed back in, and then introduced into the reactor. the fluorocarbon mixture
Perfluoro(3-dimethylaminoisobutyric acid fluoride) and perfluoro(methyl 3-dimethylaminoisobutyrate) in 5.03g are 4.24g and 0.39g, respectively. The reaction product was condensed and collected in a trap cooled to -78°C on the outlet side, yielding 2.67 g of a fluorocarbon mixture. This material was subjected to gas chromatography [liquid phase:
1,6-bis(1,1,12-trihydroperfluorododecyloxy)hexane, carrier: ^60-80 methane -Perfluoro(3-dimethylamino-2-propene) (boiling point 30-32℃) 0.50g
(yield 13.5%), cis-perfluoro(3-dimelamino-2-propene) (boiling point 33-34°C) 1.38g
(yield 37.3%), and perfluoro(3-dimethylaminopropene) (boiling point 42-43℃) 0.35g (yield
9.5%). The conversion rate at this time is 100%
It was hot. Their spectroscopic data are as follows. Trans-perfluoro(3-dimethylamino-2-propene): ¹⁹ F NMR data Chemical shift (ppm, CFCl ₃ standard) −57.6 (d, d) −113.4 (d, q) −69.3 (d, d) −156.2 (d) Coupling constant (Hz) −=3.7, −=3.7, − =22.3,
-=135, -=9.9 Mass spectrometry data m/z 283M ⁺ 264 [M-F] ⁺ 245C ₅ F ₉ N ⁺ Infrared absorption spectrum data 1756cm ^-1 (C=C) Cis-perfluoro(3-dimethylamino- 2
−propene): ¹⁹ F NMR data Chemical shift (ppm, CFCl ₃ standard) −57.5 (m) −97.7 (m) −142.1 (q, d) −69.0 (t, hept) Coupling constant (Hz) −=20.6, −=10.4, −=10.6 ,
-=2 Mass spectrometry data m/z 283M ⁺ 264 [M-F] ⁺ 195C ₄ F ₇ N ⁺ Infrared absorption spectrum data 1759cm ^-1 (C=C) Perfluoro[3-(dimethylamino)]-1-
Propene: ¹⁹ F NMR data Chemical shift (ppm, CFCl ₃ standard) -53.9 (t) -81.0 (m) -186.2 (d, d, t) -92.2 (d, d, t) -104.6 (d, d, t) Coupling constant ( Hz) −=12.0, −=12.0, −=15.8,
−=7.4, −=28.3, −=40.7, −
= 118.7, -54.2 Mass spectrometry data m/z 283M ⁺ 264 [M-F] ⁺ 202C ₃ F ₈ N ⁺ infrared absorption spectrum data 1791 cm ^-1 (C=C) Example 2 50 ml flask with reflux condenser 6.16 g of methyl ester of perfluoro(3-dimethylaminoisobutyric acid), 20 ml of methanol, and potassium hydroxide.
1.20 g and 1 ml of water were charged, and the saponification reaction was carried out at room temperature for 20 hours with magnetic stirring. After the reaction, most of the methanol was removed using a rotary evaporator, and then vacuum-dried at room temperature for 4 hours, yielding 4.11 g of a white solid substance in the flask. Thermal decomposition of this material takes about 25 minutes under vacuum (3 torr) using an oil bath and heats from 140℃ to 200℃.
℃, then 200℃ to 240℃ in another 30 minutes.
This was done by heating to a temperature raised to . The product was condensed and collected in a trap cooled with liquid nitrogen. first,
The cold trap containing the crude product was immersed in an ethanol/dry ice bath and any contaminating carbon dioxide gas was removed by vacuum suction (3 torr) for several minutes. The amount of product thus obtained was 2.18 g. When this product was analyzed in the same manner as in Example 1, 0.46 g (yield 11.2%) of trans-perfluoro(3-dimethylamino-2-propene) and 0.46 g (yield 11.2%) of cis-perfluoro(3-dimethylamino-2-propene) were found. 1.36g (yield 33.2%), 0.32g perfluoro(3-dimethylamino-1-propene)
(yield 7.7%). Example 3 Using the same reactor as in Example 1, 3 was used as the raw material.
-Product obtained by electrolytic fluorination of diethylaminoisobutyric acid methyl ester (celdrain compound)
The reaction was carried out in the same manner as in Example 1, except that . The product contains 79.4% perfluoro(3-diethylaminoisobutyric acid fluoride) by weight.
It was included. 6.71 g of the above fluorocarbon mixture [perfluoro(3-diethylaminoisobutyric acid fluoride)]
5.33 g] was fed into the reactor over a period of 30 minutes and thermally decomposed, yielding 4.43 g of fluorocarbon in the cooling trap. When this product was analyzed in the same manner as in Example 1,
trans-perfluoro(3-diethylamino-
2-propene) (boiling point 74.0-74.5℃) 0.99g (yield
23.2%), cis-perfluoro(3-diethylamino-2-propene) (boiling point 77.5-78.5°C) 3.47g
(yield 31.0%), perfluoro(3-diethylamino-1-propene) (boiling point 85.5-86.5℃) 1.00g
(Yield: 23.3%) and 0.14 g of perfluoro(N,N-diethylvinylamine) were obtained. The conversion rate in this case was 90.2%. Example 4 Using the same reactor as in Example 1, 3 was used as the raw material.
The reaction was carried out in the same manner as in Example 1, except that a product obtained by electrolytic fluorination of -pyrrolidinoisobutyric acid methyl ester (celledrain compound) was used. The product contained 83.7% by weight of perfluoro(3-pyrrolidinoisobutyric acid fluoride). 6.95 g of the above fluorocarbon mixture [perfluoro(3-pyrrolidinoisobutyric acid fluoride) 6.07
When the reactor was fed for 30 minutes and thermally decomposed, 4.64 g of fluorocarbon was obtained in the cooling trap. When this product was analyzed in the same manner as in Example 1,
trans-perfluoro(3-pyrrolidino-2-
propene) (boiling point 75.5-76.5℃) 4.06g (yield 27.5
%), cis-perfluoro(3-pyrrolidino-2
-propene) (boiling point 77.0-78.0℃) 5.07g (yield
34.3%), perfluoro(3-pyrrolidino-1-
propene) (boiling point 78.5-80.0℃) 2.23g (yield 15.1
%) and perfluoro(N-vinylpyrrolidine)
0.10g was obtained. The conversion rate was 100%. Example 5 The same reactor as in Example 1 was used, calcium carbonate (47.7 g) was used as the filler, 300°C was adopted as the reaction temperature, and 3-3 was used as the raw material.
The same method as in Example 1 was carried out except that a product obtained by electrolytically fluorinating methyl morpholino-isobutyrate (celledrain compound) was used. The product contained 84.3% by weight perfluoro(3-morpholino-isobutyric acid fluoride). 8.38 g of the above fluorocarbon mixture [perfluoro(3-morpholinoisobutyric acid fluoride) 7.06
(containing g) was fed to the reactor over a period of 38 minutes and pyrolyzed, yielding 5.74 g of fluorocarbon in the cooling trap. When this product was analyzed in the same manner as in Example 1,
trans-perfluoro(3-morpholino-2-
propene) (boiling point 83.0-83.5℃) 0.96g (yield 16.1
%), cis-perfluoro(3-morpholino-2
-propene) (boiling point 85.5-86.5℃) 1.96g (yield
32.8%), perfluoro(3-morpholino-1-
propene) (boiling point 89.5-91.0℃) 1.66g (yield 27.8
%) and perfluoro(N-vinylmorpholine)
It contained 0.31g. The conversion rate was 100%. Example 6 Using the same reactor as in Example 1, 3 was used as the raw material.
The reaction was carried out in the same manner as in Example 5, except that a product obtained by electrolytically fluorinating methyl piperidinoisobutyrate (celledrain compound) was used. The product contained 76.5% by weight perfluoro(3-piperidinoisobutyric acid fluoride). 6.37 g of the above fluorocarbon mixture [perfluoro(3-piperidinoisobutyric acid furiolide) 4.88
When the reactor was fed for 28 minutes and pyrolyzed, 4.00 g of fluorocarbon was obtained in the cooling trap. When this product was analyzed in the same manner as in Example 1,
trans-perfluoro(3-piperidino-2-
propene) (boiling point 95.0-95.5℃) 0.80g (yield 19.2
%), cis-perfluoro(3-piperidino-2
-propene) (boiling point 97.5-98.5℃) 1.87g (yield
44.7%), perfluoro(3-piperidino-1-
propene) (boiling point 107.0-108.0℃) 0.37g (yield
8.9%) and 0.49 g of perfluoro(N-vinylpiperidine) were obtained. Example 7 Using a reactor similar to Example 1, a reaction temperature of 250°C was used, and perfluoro[3-(N′-methylpiperazino)] purified by GC was used as a raw material.
-isobutyric acid fluoride] was used, but the reaction was carried out in the same manner as in Example 1. Perfluoro[3-(N'-methylpiperazino)
-Isobutyric acid fluoride] 2.14 g was fed into the reactor over a period of 9 minutes and thermally decomposed, yielding 1.30 g of fluorocarbon in the cooling trap. When this product was analyzed in the same manner as in Example 1,
Trans-perfluoro[3-(N'-methylpiperazino)-2-propene] (boiling point 106.5-108.5℃)
0.41g (yield 21.9%), cis-perfluoro[3
-(N'-methylpiperazino)-2-propene] (boiling point 110.5-111.5°C), 0.68 g (yield 36.7%) and perfluoro[3-(N'-methylpiperazino)-1
-propene] (boiling point 116.5-117.5℃) 0.50g (yield
11.6%) was obtained.

Claims (1)

[Claims] 1. General formula [In the formula, R ₁ and R ₂ 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, It may form a heterocyclic ring, a six-membered ring, or a seven-membered ring, and X is a fluorine atom, a perfluoroalkoxy group, or a -
OM (where M is a monovalent alkali metal or alkaline earth metal)] is characterized by heat-treating a perfluoro(3-disubstituted isobutyric acid) derivative at a temperature of 100 to 500°C. The general formula (C ₃ F ₅ in the formula is a 1-perfluoropropenyl group or a 2-perfluoropropenyl group, R ₁ and R ₂
has the same meaning as above) A method for producing perfluoro(3-disubstituted aminopropene).