JP6889646B2 - Method for Producing Fluorine-Containing Aliphatic Amine Hydrochloride - Google Patents

Description

The present invention relates to a method for producing a fluorine-containing aliphatic amine hydrochloride.

Conventionally, as a method for purifying amine, a method for purifying by distillation (Patent Documents 1 and 2), a method for purifying by crystallization by cooling (Patent Document 3), and a method for purifying by crystallization with a solvent (Patent Document 4). ), A method of separating into a hydrochloride (Patent Documents 5 to 6) is known.

Japanese Unexamined Patent Publication No. 49-14409 Japanese Unexamined Patent Publication No. 2011-500526 Japanese Unexamined Patent Publication No. 1-168648 Japanese Unexamined Patent Publication No. 57-51957 Japanese Unexamined Patent Publication No. 63-277649 Japanese Unexamined Patent Publication No. 2000-95735

However, no effective purification method for fluorine-containing aliphatic amines is known. Further, in the fluorine-containing aliphatic amine obtained by reducing the fluorine-containing aliphatic amide, there is a problem that a large amount of impurities are generated due to the elimination reaction of fluorine or the like. Further, there is a small difference in physical properties such as solubility and boiling point between the generated impurities and the fluorine-containing aliphatic amine, and it is difficult to obtain a highly pure fluorine-containing aliphatic amine (fluorine-containing aliphatic amine hydrochloride). There is.
An object of the present invention is to provide a method for producing a fluorine-containing aliphatic amine hydrochloride having high purity in high yield.

In the present invention, in a solution (X) containing fluorine-containing aliphatic amine (A), hydrogen chloride (B) and water, (A) is allowed to act on (B) to cause fluorine-containing aliphatic amine hydrochloride (C). After the step (I) of obtaining (I), (C) is solid-liquid separated, and an aqueous solution (F) in which (C) is dissolved in water and a solution (G) containing hydrogen chloride (B) are mixed to form a solution ( A method for producing a fluorine-containing aliphatic amine hydrochloride, which comprises a step (II) of precipitating (C) in a solution (H) after making H), wherein the step (II) puts (C) in water. This is a step of mixing a dissolved aqueous solution (F) and a solution (G) containing hydrogen chloride (B) to obtain a solution (H), and then precipitating (C) in the solution (H). Fluoroaliphatic amine hydrochloride in which the concentration of hydrogen chloride (B) in the solution (H) immediately after mixing F) and the solution (G) is 10 to 20% by weight based on the weight of (H). It is a manufacturing method of.

The method for producing a fluorine-containing aliphatic amine hydrochloride of the present invention can obtain a high-purity fluorine-containing aliphatic amine hydrochloride in high yield.
In the present invention, high purity means that there are few impurities due to the elimination reaction of fluorine.

In the present invention, in a solution (X) containing a fluorine-containing aliphatic amine (A), hydrogen chloride (B) and water, (A) is allowed to act on (B) to cause a fluorine-containing aliphatic amine hydrochloride (C). After the step (I) of obtaining (I), (C) is solid-liquid separated, and an aqueous solution (F) in which (C) is dissolved in water and a solution (G) containing hydrogen chloride (B) are mixed to form a solution ( A method for producing a fluorine-containing aliphatic amine hydrochloride, which comprises a step (II) of precipitating (C) in a solution (H) after making H), wherein the aqueous solution (F) and the solution (G) are mixed. This is a method for producing a fluorine-containing aliphatic amine hydrochloride in which the concentration of hydrogen chloride (B) in the solution (H) immediately after the solution (H) is 8 to 20% by weight based on the weight of (H).

In the present invention, the fluorinated aliphatic amine (A) is obtained by the amination reaction of the fluorinated aliphatic amine (A) obtained by reducing the fluorinated aliphatic amine (A') and the fluorinated aliphatic alcohol. The obtained (A) includes (A) obtained by a hydrogen reduction reaction of a fluorine-containing aliphatic nitrile, but from the viewpoint of easiness of purification of the fluorine-containing aliphatic amine (A), a fluorine-containing aliphatic amide ( The fluorine-containing aliphatic amine (A) obtained by reducing A') is preferable.
In the fluorine-containing aliphatic amine (A) obtained by reducing the fluorine-containing aliphatic amide (A'), the reducing agent is a metal hydride (eg, aluminum hydride, aluminum lithim hydride, boron borohydride). Sodium, lithium borohydride, lithium cyanoborohydride, dihydro-bis (2-methoxyethoxy) sodium aluminate, etc.), borane complexes (eg, borane-THF complex and catecholborane, etc.), dibutylaluminum hydride and their metal hydrogens. Examples thereof include a mixture of the compound and a Lewis acid (for example, aluminum chloride, titanium tetrachloride, cobalt chloride, borontrifluoride, etc.). Of these, from the viewpoint of productivity, those obtained by reducing the fluorine-containing aliphatic amide (A') in the presence of the boron hydride compound (D) and the aluminum salt (E) are preferable.

In the fluorine-containing aliphatic amine (A) obtained by reducing the fluorine-containing aliphatic amide (A'), a large amount of impurities are generated due to the desorption reaction of fluorine, etc., and these impurities have solubility, boiling point, etc. The difference in physical properties is small, and it is difficult to obtain the desired fluorine-containing aliphatic amine with high purity by the conventional method. However, in the present invention, in the solution (X) containing the fluoroaliphatic amine (A), the hydrogen chloride (B) and water, when the (B) is allowed to act on the (A), the solution (H) is used. By setting the concentration of (B) in the above range, the target fluoroaliphatic amine (A) can be efficiently precipitated as a hydrochloride, and a highly pure fluoroaliphatic amine hydrochloride can be obtained.

The boron hydride compound (D) includes a compound (D1) represented by the following general formula (1).
M (BH ₄ ) _n (1)
In the general formula (1), M represents a metal or atomic group that can be an n-valent cation, and n represents an integer of 1 to 3.
As M, those that can be monovalent cations {alkali metals (lithium, sodium, potassium, etc.), onium, etc.}, those that can be divalent cations {alkali earth metals (magnesium, calcium, etc.)}, 3 Examples thereof include those that can be cations of valence {aluminum, etc.}.
The onium includes ammonium and quaternary ammonium (including those having a hydrocarbon group having 1 to 24 carbon atoms, and specifically, tetramethylammonium, tetraethylammonium, trimethylethylammonium, tetrapropylammonium, tetrabutylammonium. , Tetraphenylammonium and trimethylbenzylammonium, etc.), phosphonium (including those having a hydrogen atom or a hydrocarbon group having 1 to 24 carbon atoms, specifically, tetrabutylphosphonium, tetraphenylphosphoniu, etc.), sulfonium (, etc.), sulfonium ( Those having a hydrogen atom or a hydrocarbon group having 1 to 24 carbon atoms are included, and specific examples thereof include trimethylsulfonium, triethylsulfonium and triphenylsulfonium).
As M, sodium is preferable from the viewpoint of reactivity and ease of purification after the reaction.

Specific examples of the boron borohydride compound (D) include lithium borohydride, sodium borohydride, potassium borohydride, aluminum borohydride, tetramethylammonium borohydride and the like.
As (D), sodium borohydride is preferable from the viewpoint of reactivity and ease of purification after the reaction.
As (D), one type may be used, or two or more types may be used in combination.

The aluminum salt (E) includes a trivalent inorganic aluminum compound, specifically, a halide of aluminum (aluminum fluoride, aluminum chloride, aluminum bromide, aluminum iodide, etc.), aluminum hydroxide, nitrate. Examples thereof include aluminum, aluminum sulfate and aluminum phosphate.
As (E), aluminum chloride is preferable from the viewpoint of reactivity and stability of (E).
As (E), one type may be used, or two or more types may be used in combination.

In the reduction reaction of the fluorine-containing aliphatic amide (A'), the molar ratio {(D): (E)} of the boron hydride compound (D) and the aluminum salt (E) is the safety and the produced fluorine-containing fat. From the viewpoint of ease of purification of the group amine, 9: 4 to 9:10 is preferable, and 9: 4 to 9: 6 is more preferable.
In a normal reduction reaction of an amide compound, (D): (E) is used at a ratio of 9: 3, but in the present invention, the fluorine-containing aliphatic amide can be safely reduced with a high reaction rate by setting the above range. This is preferable because a highly pure fluorine-containing aliphatic amine hydrochloride can be obtained.
When (D) is 9 mol and (E) is 4 mol or more, the reaction rate of the reduction reaction is high, which is preferable. Further, when (E) is 10 mol or less with respect to 9 mol of (D), a large amount of hydrogen is generated from the surplus (E) in the quenching step after the reaction, and there is no need to perform dangerous work. Further, the produced fluorine-containing aliphatic amine is easily dissolved in the reaction solvent and separated from the reducing agent and the filtration residue without biasing the reaction solution to acidity.

In the present invention, the fluorine-containing aliphatic amide (A') includes a compound represented by the following general formula (2).
NH ₂ CO-Rf-CONH ₂ (2)
In the general formula (2), Rf is a perfluoro linear alkylene group having 1 to 20 carbon atoms which may contain an ether bond or a perfluoro branched alkylene group having 1 to 20 carbon atoms which may contain an ether bond. Represent.

As the fluorine-containing aliphatic amide (A'), for example, a compound represented by the following general formula (3) is included.
NH ₂ CO (CF ₂ ) _r CONH ₂ (3)
In the general formula (3), r represents an integer of 1 to 20.

As the fluorine-containing aliphatic amide (A'), the compound represented by the general formula (2) is preferable, and the compound represented by the general formula (3) is more preferable, from the viewpoint of easiness of reduction.

In the reduction reaction of the fluoroaliphatic amide (A'), the molar ratio of the boron hydride compound (D) to the amide group in the fluoroaliphatic amide (A') {(D) / (A') The amide group} is preferably 9 / 3.5 to 9/9 from the viewpoint of reactivity.
In the reduction reaction of the amide compound, the molar ratio of the amide group in (D) and (A') is usually 3/4 {9/12}, but by setting the above range, It is preferable because the reaction rate is higher, there are few impurities such as those desorbed from fluorine, and a high-purity fluorine-containing aliphatic amine can be obtained.

The reduction reaction of the fluoroaliphatic amide (A') can reduce (A') in the presence of the boron hydride compound (D) and the aluminum salt (E) in an ether solvent from the viewpoint of reactivity. preferable.
The ether solvent includes an ether compound having 4 to 8 carbon atoms, and specifically, an acyclic ether solvent {diethyl ether, diisopropyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, etc.} and a cyclic ether solvent {1,4- Dioxane, tetrahydrofuran, etc.} and the like.
As the ether solvent, an acyclic ether solvent is preferable, and diethylene glycol dimethyl ether is more preferable, from the viewpoint of the solubility of (A') and a high boiling point.

The temperature of the reaction solution in the reduction reaction of the fluorine-containing aliphatic amide (A') is preferably 25 to 100 ° C. from the viewpoint of reactivity and safety.

In the reduction reaction of the fluorinated aliphatic amide (A'), the time for allowing the boron hydride compound (D) and the aluminum salt (E) to act on the fluorinated aliphatic amide (A') is 5 from the viewpoint of reactivity. ~ 50 hours is preferred.

An example of a method of reducing a fluorinated aliphatic amide (A') to obtain a fluorinated aliphatic amine (A) is shown.
(1) Borane hydride compound (D), aluminum salt (E), fluorine-containing aliphatic amide (A') and ether solvent were added to the reaction vessel to prepare a reaction solution, which was prepared at 25 to 100 ° C. under stirring (A). ') Reduction reaction is performed.
(2) After 5 to 50 hours from the start of the reduction reaction of (A'), water is added to end the reduction reaction.

In the above (1), in the order of adding the fluoroaliphatic amide (A'), the boron hydride compound (D), the aluminum salt (E) and the ether solvent, (D) and (A') are added to the ether solvent. It is preferable to drop the compound (E) dispersed or dissolved in an ether solvent into the compound dispersed or dissolved in. It is also possible to drop (E) and (A') dissolved in an ether solvent and (D) dispersed or dissolved in an ether solvent, but in general, (D) is difficult to dissolve in an ether solvent. Therefore, the dropping pump may be clogged.

In the above (2), the amount of water is determined from the viewpoint of ease of purification of the fluoroaliphatic amine hydrochloride, the fluoroaliphatic amide (A'), the ether solvent, the boron hydride compound (D) and aluminum. It is preferably 1 to 20% by weight, particularly preferably 5 to 15% by weight, based on the total weight of the salt (E).

The fluorine-containing aliphatic amine (A) obtained by reducing the fluorine-containing aliphatic amide (A') includes a compound represented by the following general formula (4).
_{NH 2 -CH 2 -Rf-CH 2} -NH 2 (4)
In the general formula (4), Rf is a perfluoro linear alkylene group having 1 to 20 carbon atoms which may contain an ether bond or a perfluoro branched alkylene group having 1 to 20 carbon atoms which may contain an ether bond. Represent.

As the fluorine-containing aliphatic amine (A), for example, a compound represented by the following general formula (5) is included.
NH ₂ −CH ₂ − (CF ₂ ) _r −CH ₂ −NH ₂ (5)
In the general formula (5), r represents an integer of 1 to 20.

As the fluorine-containing aliphatic amine (A), the compound represented by the general formula (4) is preferable, and the compound represented by the general formula (5) is more preferable, from the viewpoint of ease of purification.

In the production method of the present invention, hydrogen chloride (B) is allowed to act on the fluorine-containing aliphatic amine (A) in the solution (X) containing the fluorine-containing aliphatic amine (A), hydrogen chloride (B) and water. After the step (I) of obtaining the fluorine-containing aliphatic amine hydrochloride (C), the fluorine-containing aliphatic amine hydrochloride (C) was separated into a solution, and the aqueous solution (F) in which (C) was dissolved in water was combined with the solution (F). A fluorine-containing aliphatic amine hydrochloride comprising a step (II) of mixing a solution (G) containing hydrogen chloride (B) to prepare a solution (H) and then precipitating (C) in the solution (H). In the production method, the concentration of hydrogen chloride (B) in the solution (H) immediately after mixing the aqueous solution (F) and the solution (G) is 8 to 20% by weight based on the weight of (H). It is a method for producing a certain fluorine-containing aliphatic amine hydrochloride.
In the present invention, it is excellent in stability over time that the fluorine-containing aliphatic amine (A) is not a other salt (fluoride salt, nitrate, carbonate, sulfate, etc.) but a fluorine-containing aliphatic amine hydrochloride. This is because it is preferable because it can be phosgenated without salt substitution at the time of isocyanate formation.
In addition, in the production of fluorine-containing aliphatic amine hydrochloride using hydrogen chloride, the solubility of fluorine-containing aliphatic amine hydrochloride is efficiently improved by using ions (chloride ions) of the same type as the target salt. This is because it can be changed. Therefore, in the present invention, by adjusting the concentration of hydrogen chloride, impurities having only a slight solubility, such as those desorbed from fluorine, can be efficiently removed, and the purity is high and the yield of fluorine-containing fat is high. Group amine hydrochloride can be produced.
In the step (1), the concentration of (B) in the solution (X) immediately after the preparation of the solution (X) is the purity and yield of the fluoroaliphatic amine hydrochloride based on the weight of the solution (X). From the viewpoint, it is preferably 1 to 10% by weight, more preferably 2 to 7% by weight.
When the concentration of (B) is 1% by weight or more, a high-yield fluorinated aliphatic amine hydrochloride can be obtained, and when it is 10% by weight or less, a high-purity fluorinated aliphatic amine hydrochloride can be obtained. be able to.
In the step (1), the concentration of (A) in the solution (X) immediately after the preparation of the solution (X) is the weight of the solution (X) from the viewpoint of the purity and yield of the fluorinated aliphatic amine hydrochloride. As a reference, 1 to 10% by weight is preferable.
In addition, in the solution (X) immediately after the preparation of (X), the amino group in (A) and hydrogen chloride do not form a salt, and the fluorinated aliphatic amine hydrochloride is not formed. To do.

In step (I), the molar ratio of the amino group of the fluorine-containing aliphatic amine (A) to hydrogen chloride (B) in the solution (X) immediately after the preparation of the solution (X) {(A) :( B)} Is preferably 1: 2 to 1:10 from the viewpoint of the purity of the fluorine-containing aliphatic amine hydrochloride.

In the step (I), the temperature of the solution (X) is preferably 10 to 40 ° C. from the viewpoint of the yield and purity of the fluoroaliphatic amine hydrochloride.
In the step (I), the time when the temperature of the solution (X) is the above temperature is 80% or more of the time in the step (I) from the viewpoint of the yield and purity of the fluoroaliphatic amine hydrochloride. More preferably, the time is 90% or more.
Even if, for example, the first 20% of the time of step (I) is outside the above range (for example, a temperature exceeding 40 ° C.), the yield and purity are within the above range within 80% or more of the time. Does not make a big difference.
In step (I), the time for allowing (B) to act on (A) {including those in which the amino group in (A) is an ammonium chloride group} is the yield of the fluorine-containing aliphatic amine hydrochloride and the time. From the viewpoint of purity, it is preferably 10 minutes to 24 hours, more preferably 20 minutes to 24 hours.

In the production method of the present invention, after the step (I), the fluorine-containing aliphatic amine hydrochloride (C) is solid-liquid separated, and the aqueous solution (F) in which (C) is dissolved in water and hydrogen chloride (B) are mixed. A method for producing a fluorine-containing aliphatic amine hydrochloride, which comprises a step (II) of precipitating (C) in the solution (H) after mixing with the containing solution (G) to obtain a solution (H). The concentration of hydrogen chloride (B) is 8 to 20% by weight based on the weight of the solution (H) immediately after mixing the aqueous solution (F) and the solution (G).

Examples of the solid-liquid separation method include removing the supernatant by decantation after precipitating by filtration, centrifugation or the like.

In the step (II), the content of the fluorinated aliphatic amine hydrochloride (C) in the aqueous solution (F) before being dissolved in the aqueous solution (F) is the content of the aqueous solution (F) from the viewpoint of purity and yield. Based on the weight, 5 to 30% by weight is preferable.
It is assumed that the fluorinated aliphatic amine hydrochloride (C) is dissociated into the fluorinated aliphatic amine (A) and hydrogen chloride (B) by dissolving in (F).

In step (II), an amino group (-) derived from hydrogen chloride (B) and a fluoroaliphatic amine hydrochloride (C) in the solution (H) immediately after mixing the aqueous solution (F) and the solution (G). The molar ratio to NH ₂ ) {(B) _{:( −NH 2} )} is preferably 5: 1 to 22: 1, more preferably 5: 1 to 20: 1 from the viewpoint of purity and yield. ..

In the step (II), the temperature of the solution (H) is preferably 10 to 40 ° C. from the viewpoint of the yield and purity of the fluoroaliphatic amine hydrochloride.
In the step (II), the time during which the temperature of the solution (H) {including the solution in which the fluorinated aliphatic amine hydrochloride is precipitated in the solution (H)} is the above temperature is the fluorinated aliphatic amine hydrochloride. From the viewpoint of the yield and purity of the above, the time is 80% or more, more preferably 90% or more of the step (II).
Even if the first 20% of the time in step (II) is outside the above range (for example, a temperature exceeding 40 ° C.), if it is within the above range in 80% or more of the time, the yield and purity will be increased. There is no big difference.
In step (II), the time for allowing (B) to act on (A) {including those in which the amino group in (A) is an ammonium chloride group} is the yield of the fluorine-containing aliphatic amine hydrochloride and the time. From the viewpoint of purity, it is preferably 10 minutes to 24 hours, more preferably 20 minutes to 24 hours.

The content of hydrogen chloride (B) in the solution (H) immediately after mixing the aqueous solution (F) and the solution (G) is 8 to 20% by weight, and the purity and yield of the fluoroaliphatic amine hydrochloride From the viewpoint of rate, 10 to 20% by weight is preferable based on the weight of the solution (H).
The content of the fluoroaliphatic amine (A) in the solution (H) immediately after mixing the aqueous solution (F) and the solution (G) is determined from the viewpoint of the purity and yield of the fluoroaliphatic amine hydrochloride. Based on the weight of the solution (H), it is preferably 3 to 15% by weight, more preferably 3 to 10% by weight.
The content of water in the solution (H) is preferably 65 to 89% by weight, more preferably 70 to 87% by weight, based on the weight of the solution (H), from the viewpoint of the purity of the fluoroaliphatic amine hydrochloride. %.
It is assumed that the fluorinated aliphatic amine (A) and hydrogen chloride (B) are dissociated in the solution (H) immediately after the aqueous solution (F) and the solution (G) are mixed.

The step (II) does not dissolve (C) in a solution containing hydrogen chloride (B) and water, but contains (C), an aqueous solution (F) dissolved in water, and hydrogen chloride (B). By mixing with the solution (G), impurities contained in the crystal can be efficiently removed.

In the production method of the present invention, it is preferable to carry out the step (II) once or a plurality of times from the viewpoint of the purity of the fluoroaliphatic amine hydrochloride.
Further, from the viewpoint of the purity and yield of the fluorine-containing aliphatic amine hydrochloride, the number of steps (II) is preferably 1 to 5 times.

The method for producing a fluorinated aliphatic amine hydrochloride of the present invention has high purity and can obtain a fluorinated aliphatic amine hydrochloride in a high yield.
Further, by using the obtained fluorine-containing aliphatic amine hydrochloride, highly pure fluorine-containing aliphatic amine and fluorine-containing aliphatic isocyanate can be obtained.

The fluoroaliphatic amine hydrochloride obtained by the production method of the present invention can be obtained as a fluoroaliphatic amine by dissolving it in an alkaline aqueous solution such as an aqueous sodium hydroxide solution, dehydrochlorinating it and distilling it.
Since the fluorinated aliphatic amine hydrochloride obtained by the production method of the present invention has few impurities, the fluorinated aliphatic amine obtained by dehydrochlorination is also high in purity.

Examples of the alkaline aqueous solution include hydroxides of alkali metals (lithium, sodium, potassium, etc.) and hydroxides of alkaline earth metals (magnesium, calcium, etc.).

The distillation conditions are not particularly limited, and general distillation conditions can be used.
The pressure is preferably 10 to 50 torr, more preferably 10 to 20 torr, from the viewpoint of thermal stability of the compound.
The temperature is preferably 60 to 120 ° C., more preferably 80 to 100 ° C. from the viewpoint of thermal stability of the compound.

The obtained fluorine-containing aliphatic amine may be phosgenated by a known method (for example, International Publication No. 2008/086922) to obtain a fluorine-containing aliphatic isocyanate.

The fluorinated aliphatic amine hydrochloride obtained by the production method of the present invention may be phosgenated by a known method (for example, Organic Syntheses, 1963, Coll. Vol 4, p521, etc.) to obtain a fluorinated aliphatic isocyanate. By using the fluorinated aliphatic amine hydrochloride obtained by the production method of the present invention, a fluorinated aliphatic isocyanate having high purity can be obtained.

The fluorinated aliphatic isocyanate obtained by phosgenation using the fluorinated aliphatic amine hydrochloride obtained by the production method of the present invention has high purity and is therefore useful not only for experiments but also for medical and electronic purposes. ..

Hereinafter, the present invention will be further described with reference to Examples and Comparative Examples, but the present invention is not limited thereto. Hereinafter, unless otherwise specified, parts indicate parts by weight. Examples 5 and 7 are reference examples.

<Manufacturing example 1>
<Production of filtered supernatant (1) containing fluorine-containing aliphatic amine (A1)>
2100 parts of diethylene glycol dimethyl ether was placed in a glass container, and 170 parts (4.5 mol parts) of tetrahydroborohydride and 288 parts of octafluorohexanediamide (manufactured by Wako Pure Chemical Industries, Ltd.) (2 moles of amide group). A molar portion) was added to prepare a liquid (I) dispersed until the whole became uniform. Further, 2200 parts of diethylene glycol dimethyl ether was placed in another glass container, and 300 parts (2.25 mol parts) of aluminum chloride was slowly added to prepare a liquid (II) dispersed until the whole became uniform. The liquid (II) was added dropwise to the liquid (I) at a rate of foaming at 20 to 30 ° C. and heat generation did not become intense. After dropping the whole amount, the temperature was raised to 65 to 75 ° C. and the reaction was carried out for 20 hours.
Then, 575 parts of ion-exchanged water was added to obtain a fluorine-containing aliphatic amine-containing aqueous solution (1).
The fluorine-containing aliphatic amine-containing aqueous solution (1) is filtered through a filter paper (Advantech No. 2) to remove solid inorganic salts and the like, and octafluorohexanediamine is added as the fluorine-containing aliphatic amine (A1) by 5.25 weight. 5200 parts of the filtered supernatant (1) containing% was obtained.

<Manufacturing example 2>
<Production of filtered supernatant (2) containing fluorine-containing aliphatic amine (A2)>
In Production Example 1, "decafluoroheptane diamide 388 parts (2 mol parts as the number of moles of the amide group)" is used instead of "288 parts of octafluorohexanediamide (2 mol parts as the number of moles of the amide group)". In the same manner except for the above, 5300 parts of a filtered supernatant (2) containing 6.86% by weight of decafluoroheptanediamine as a fluoroaliphatic amine (A2) was obtained.

<Manufacturing example 3>
<Production of filtered supernatant (3) containing fluorine-containing aliphatic amine (A1)>
Regarding the liquid (I) of Production Example 1, sodium tetrahydroboron was replaced with "170 parts (4.5 mol parts)" to be "85 parts (2.25 mol parts)", and in the liquid (II), aluminum chloride was ". 266 parts (2 mol parts) "is replaced with" 500 parts (3.75 mol parts) ", and ion-exchanged water is replaced with" 575 parts "and" 1415 parts "is added. 6000 parts of the filtered supernatant (3) containing 4.50% by weight of octafluorohexanediamine as the aliphatic amine (A1) was obtained.

<Manufacturing example 4>
<Production of filtered supernatant (4) containing fluorine-containing aliphatic amine (A1)>
5400 parts of the filtered supernatant (1) obtained in Production Example 1 was concentrated under the conditions of 35 mmHg and 75 ° C. until the filtered supernatant reached 2600 parts, and 10 octafluorohexanediamine was added as a fluorine-containing aliphatic amine (A1). 2600 parts of the filtered supernatant (4) containing 5.5% by weight was obtained.

<Manufacturing example 5>
<Production of filtered supernatant (5) containing fluorine-containing aliphatic amine (A3)>
In Production Example 1, "Tetrafluorobutanediamide 188 parts (2 mol parts as the number of moles of the amide group)" is used instead of "288 parts of octafluorohexanediamide (2 mol parts as the number of moles of the amide group)". In the same manner except for the above, 5100 parts of a filtered supernatant (5) containing 2.79% by weight of tetrafluorobutanediamine as a fluoroaliphatic amine (A3) was obtained.

<Manufacturing example 6>
<Production of filtered supernatant (6) containing fluorine-containing aliphatic amine (A4)>
In Production Example 1, instead of "288 parts of octafluorohexanediamide (2 mol parts as the number of moles of the amide group)", "588 parts of hexadecafluorodecandamide (2 mol parts as the number of moles of the amide group)" is used. In the same manner except for the above, 5400 parts of a filtered supernatant (6) containing 8.49% by weight of hexadecafluorodecanediamine as a fluoroaliphatic amine (A4) was obtained.

<Example 1>
In step (I), 700 parts (6.8 mol) of a 35% hydrogen chloride aqueous solution was added to 5200 parts of the filtered supernatant (1) containing octafluorohexanediamine as the fluoroaliphatic amine (A1) obtained in Production Example 1. Part) was added to make a solution (X), the temperature was adjusted to 20 ° C., and after 10 hours, the precipitated amine hydrochloride was collected by filtration with a filter paper (Advantech No. 2), and a fluorine-containing aliphatic amine hydrochloride (C1) was collected. ) Was obtained in 260 copies.
In step (II), 100 parts of the obtained fluorine-containing aliphatic amine hydrochloride (C1) was dissolved in 800 parts of ion-exchanged water at 30 ° C. to prepare an aqueous solution (F), which was 35.5% by weight at 25 ° C. 570 parts of the aqueous hydrogen chloride solution (G) was added to prepare a solution (H), which was left in a thermostat at 25 ° C. for 1 hour to precipitate (C1), and then the precipitated amine hydrochloride was subjected to filter paper (Advantech No. 2). It was recovered to obtain a fluorine-containing aliphatic amine hydrochloride (C1).
The operation of the above step (II) was repeated twice more to obtain a fluorine-containing aliphatic amine hydrochloride (1).
The purity of the obtained fluorine-containing aliphatic amine hydrochloride (1) was measured by the following measuring method. In addition, the yield was calculated from the amount of the obtained fluorine-containing aliphatic amine hydrochloride (1). The results are shown in Table 1.
Yield of amine hydrochloride in step (I) (1) (%) = (amount / molecular weight of recovered fluoroaliphatic amine hydrochloride) / (number of moles of charged fluoroaliphatic amide) × 100
Yield of amine hydrochloride in step (II) (2) (%) = (Amount / molecular weight of fluoroaliphatic amine hydrochloride recovered in Example 1) / (Fluorine-containing acid charged in first step (II)) Amount / molecular weight of aliphatic amine hydrochloride)
Yield in all steps (3) (%) = Yield (1) x Yield (2) / 100

<Examples 2 to 14>
In Example 1, the type and amount of the filtered supernatant in step (I), the amount of hydrogen chloride aqueous solution, the type and amount of hydrochloride in step (II), the amount of solution (G), the amount of ion-exchanged water, The temperature of the incubator and the number of steps (II) were set in the same manner except as shown in Table 1 or 2, to obtain fluorine-containing aliphatic amine hydrochlorides (2) to (14), and the purity was obtained. And the yield were calculated. The results are shown in Table 1 or 2.

<LC / MS analysis conditions>
Equipment: LCMS-8030 (manufactured by Shimadzu Corporation)
Mobile phase:
X: 10 mM ammonium acetate aqueous solution / methanol = 80/20 (v / v%)
Y: Acetonitrile X / Y = 80/20 (constant)
Flow velocity: 0.2 mL / min
Column: InnertSstein C18 (particle size: 2.0 μm x inner diameter: 2.1 mm x length 100 mm) (manufactured by GL Sciences)
Analysis mode: During reduction of octafluorohexanediamide
SIM (+) 261.00, 243.00
During reduction of decafluorooctanediamide
SIM (+) 381.00, 363.00
Ion source: ESI (±)
Injection volume: 0.5 μL

<Comparative Examples 1 and 2>
In the step (II) of Example 1, the same procedure was carried out except that the amount of the solution (G) was changed as shown in Table 1, and the fluorine-containing aliphatic amine hydrochlorides (1') to (2') were added. Obtained. The purity and yield of the obtained fluorine-containing aliphatic amine hydrochloride were measured by the following measuring methods. The results are shown in Table 2.

From the results of Tables 1 and 2, it can be seen that in Comparative Example 1 in which the concentration of hydrogen chloride is 8.4 % by weight, the yield of the amine hydrochloride in all the steps is as low as 31%. It can also be seen that if the concentration of hydrogen chloride is too high, 22.6 % by weight, the purity of the amine hydrochloride is as low as 96.4%.
On the other hand, in the production methods of Examples 1 to 4, 6 and 8 to 14 in which the concentration of hydrogen chloride is in the range of 10 to 20% by weight, a high-purity amine hydrochloride having a purity of 99% or more is yielded in all steps. It can be seen that the yield is as good as 50 to 70%.

According to the method for producing a fluorine-containing aliphatic amine hydrochloride of the present invention, a fluorine-containing aliphatic amine hydrochloride having a small amount of impurities such as those desorbed from fluorine and having high purity can be obtained in good yield. Further, the fluorinated aliphatic isocyanate obtained by phosgenation using the fluorinated aliphatic amine hydrochloride obtained by the production method of the present invention has high purity and is therefore useful not only for experiments but also for medical and electronic purposes. Is.

Claims (6)

A step of reacting (A) with (B) in a solution (X) containing a fluorine-containing aliphatic amine (A), hydrogen chloride (B) and water to obtain a fluorine-containing aliphatic amine hydrochloride (C) ( After I), (C) was solid-liquid separated, and an aqueous solution (F) in which (C) was dissolved in water and a solution (G) containing hydrogen chloride (B) were mixed to obtain a solution (H). A method for producing a fluorine-containing aliphatic amine hydrochloride, which comprises a step (II) of precipitating (C) in the solution (H).
In step (II), an aqueous solution (F) in which (C) is dissolved in water and a solution (G) containing hydrogen chloride (B) are mixed to obtain a solution (H), and then in the solution (H). This is a step of precipitating (C).
The concentration of hydrogen chloride (B) in the solution (H) immediately after mixing the aqueous solution (F) and the solution (G) is 10 to 20% by weight based on the weight of (H). Method for producing hydrochloride. Mol of hydrogen chloride (B) in solution (H) immediately after mixing aqueous solution (F) and solution (G) and amino group (-NH _{2) derived from fluoroaliphatic amine hydrochloride (C).} The method for producing a fluorine-containing aliphatic amine hydrochloride according to claim 1, wherein the ratio {(B) :( −NH _{2)} is 5: 1 to 20: 1.} The method for producing a fluorine-containing aliphatic amine hydrochloride according to claim 1 or 2, wherein the temperature of the solution (H) is 10 to 40 ° C. in 80% or more of the time of the step (II). The fluorinated aliphatic amine according to any one of claims 1 to 3 , wherein the operation of carrying out the step (II) using the fluorinated aliphatic amine hydrochloride (C) obtained by solid-liquid separation is performed 1 to 5 times. Method for producing amine hydrochloride. The method for producing a fluorinated aliphatic amine hydrochloride according to any one of claims 1 to 4, wherein the fluorinated aliphatic amine (A) is a compound represented by the following general formula (5).
NH _2- CH _2- (CF ₂ ) _r- CH _2- NH ₂ (5)
[In the general formula (5), r represents an integer of 1 to 20. ] Claimed that the fluoroaliphatic amine (A) is a fluoroaliphatic amine obtained by reducing the fluoroaliphatic amide (A') in the presence of the boron hydride compound (D) and the aluminum salt (E). Item 8. The method for producing a fluoroaliphatic amine hydrochloride according to any one of Items 1 to 5.