WO2002081081A1

WO2002081081A1 - Composition based on an amine compound and ammonium bifluoride and use thereof

Info

Publication number: WO2002081081A1
Application number: PCT/FR2002/001097
Authority: WO
Inventors: Hubert Jean Blancou; Franck Daniel Guillen
Original assignee: Centre National De La Recherche Scientifique (C.N.R.S.); Universite De Montpellier Ii
Priority date: 2001-04-09
Filing date: 2002-03-28
Publication date: 2002-10-17
Also published as: FR2823205A1; FR2823205B1

Abstract

The invention relates to a composition comprising at least one amine-containing compound and ammonium bifluoride, the use thereof as a fluorinating agent and a method for preparing perfluoroalkanesulphonyl fluoride using said fluorinating agent.

Description

COMPOSITION BASED ON AN AMINE COMPOUND AND AMMONIUM BIFLUORIDE AND USE THEREOF

The present invention relates to a composition comprising at least one amine and ammonium bifluoride, the use of this composition as fluorinating agent and a process for preparing perfluoroalkanesulfonyl fluoride using this fluorinating agent.

An electrochemical fluorination process (called ECF) which allows the synthesis of perfluoroalkanesulfonic acid fluoride and these derivatives from alkane sulfonic acid chloride or carbohydrated sulfone has been described in particular in US patent 2732398. However, the products resulting from these syntheses are mixtures of isomers with perfluorinated chains (CnF2n + 1, n> 1) variously branched.

In US Patents 2,809,990, 2,845,573 and 3,403,122 from 3M, these fluorides of perfluoroalkanesulfonic acid are described as intermediate products in the synthesis of derivatives for treating textiles, leather and paper. They can in particular be used to obtain perfluoroalkanesulfonamides which find application as paper treatment agents or insecticides. The sulphonic acids prepared by hydrolysis of perfluoroalkanesulphonyl fluorides are precursors of superacids used as a catalyst in carbocationic synthesis.

The synthesis of A7-perfluoroal ylsulfonyl fluoride from n-perfluoroalkylsulfonyl chloride has been described by a nucleophilic substitution reaction for chlorine with a fluorine in a dissociating solvent (formamide or sulfolane) (S. Bénéfice-Malouet, H. Blancou, R. Teissedre and A. Commeyras,

Journal of Fluorine Chemistry, 31 (1986) 319-332).

The main known fluorinating agents (see A. Lantz, Engineering technique, Treaty process engineering, J5 670 1-8), such as (NEt3.3HF),

(NH4F.HF), NaF, KF, do not give satisfactory results. More particularly, with NaF and KF, the reactivity is low, with NEt3.3HF or

NH4F.HF the reaction poses corrosion problems. In addition, the use of these reagents involves a step of separation of the products obtained, difficult to implement, expensive and often incompatible with high yields. It was unexpectedly found that this exchange could take place remarkably in a biphasic medium (H2θ-methylene chloride

(CH2CI2) or H2θ / 4-methyl-2-pentanone ((CH3) 2CHCH2COCH3) using new fluorinating mixtures prepared from amines (primary, secondary or tertiary) and ammonium bifluoride (NF ^ F.HF ).

The present invention therefore aims to provide new high performance fluorinating agents.

It also aims to propose a process for the preparation of fluorinated compounds using these fluorinating mixtures having very satisfactory yields and kinetics.

These processes using these fluorinating mixtures make it possible to limit the corrosion of the materials (reactors) used. It also becomes possible to change scale in production. The purification of the final product obtained is also made extremely easy and effective by these methods. These and other objects can be achieved by the present invention which relates to a composition comprising at least one amino compound and ammonium bifluoride (NH4F, HF).

More particularly, the amino compound is a primary, secondary or tertiary amine of formula (I) NH3_ _x (Rι) _X) in which x represents 1, 2 or 3, Rj represents a linear or saturated or unsaturated CJ-C20 alkyl radical , branched or forms a ring with the nitrogen atom, possibly aromatic.

Among the linear or branched C1-C20 alkyl radicals, mention may in particular be made of the methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, pentyl and hexyl, heptyl, octyl, nonyl, dodecyl, pentadecyl radical. Preferred is the C1-C4 alkyl radical and more particularly the methyl, ethyl, propyl or butyl radical.

When R 1 forms a ring with nitrogen, the amino compound can be cyclic of saturated C2-C8, such as in particular cyclohexylamine or piperidine, or unsaturated. It is then advantageously aromatic, such as in particular pyridine, pyrimidine or imidazole.

Advantageously, the composition according to the invention is an aqueous composition. The molar ratio of the amino compound and the ammonium bifluoride is advantageously between 0.8 and 1.2; preferably it is 1.

The pH of the composition can vary to a large extent, depending on the nature and amounts of the compounds present. Generally, it is between 4 and 8, advantageously between 5 and 7.5.

The composition according to the invention can be prepared by simple mixing of the constituents. According to a particular mode, the amino compound is brought into contact with water, the ammonium bifluoride is then added, advantageously by fraction. Advantageously, the process for preparing the composition according to the invention is carried out at a temperature between 0 and room temperature (20-30 ° C). Preferably, this temperature is between 5 and 20 ° C.

The present invention also relates to the use of the composition described above as a fluorinating agent.

Thus, this use is particularly suitable for a process for the preparation of perfluoroalkanesulfonyl fluoride.

It therefore relates to a process for the preparation of perfluoroalkanesulfonyl fluoride, characterized in that it comprises the reaction between the composition according to the invention and at least one perfluoroalkanesulfonyl halide.

The process according to the invention has the advantage of making possible the synthesis of t? -Perfluoroalkylsulfonyl fluoride, ie with a linear alkyl chain. The perfluoroalkanesulfonyl halides can be chosen from iodides, bromides and preferably perfluoroalkanesulfonyl chlorides.

Perfluoroalkanesulfonyl halides are preferably compounds of formula RfSθ2X where X represents a halogen atom and Rf represents a linear or branched perfluorinated chain containing from 1 to 12 carbon atoms. Advantageously, the perfluorinated chain is linear. It preferably has 2, 4, 6 or 8 carbon atoms. The perfluoroalkanesulfonyl halides can in particular be obtained according to the methods described by PJ Stang et al. in Synthesis 1982, 85, by RN Haszeldine et al. in J. Chem. Soc. 1955, 2901, or also in FR 76 06303 and US 3732398. Perfluoroalkanesulfonyl halides can also be obtained by contacting the alkali metal salt, preferably sodium, perfluoroalkane sulfonic acid corresponding with at least one agent halogenation, preferably a chlorinating agent, such as in particular chlorine or sulfuryl chloride. This step can in particular be carried out in an aqueous medium or, surprisingly, in a halogenated organic solvent, more particularly chlorinated, such as in particular dichloromethane or dichloroethane.

Said reaction between the composition according to the invention and at least one perfluoroalkanesulfonyl halide of the process according to the invention is advantageously carried out in a two-phase medium.

Thus, preferably, the solvents used correspond to a mixture of water and at least one organic solvent which is not soluble in water, such as in particular methylene or ethylene chloride, 4-methyl-2-pentanone , or chloroform.

Thus, in the case where the perfluoroalkanesulfonyl chloride used was obtained by chlorination in a solvent such as dichloromethane or dichloroethane as described above, the method according to the invention has the advantage of not necessarily carrying out a step of separation of the perfluoroalkanesulfonyl chloride obtained before being brought into contact with the fluorinating agent.

In order to carry out a quantitative reaction, the perfluoroalkanesulfonyl halide and the ammonium bifluoride present in the composition according to the invention are advantageously used in an amount close to the stoichiometry of the reaction, that is to say at a molar ratio between the perfluoroalkanesulfonyl halide and the ammonium bifluoride preferably equal to 1 ± 0.2. The quantities of solvents which can be used are excessively variable and depend on the solubilities of the compounds used in said solvents. The amounts used are generally between 500 ml and 1000 ml of solvents per mole of perfluoroalkanesulfonyl halide. The reaction temperature of the process according to the invention can vary to a large extent. In practice, the temperature is generally between 0 and 40 ° C. Advantageously, the temperature is maintained at room temperature (between about 20 and 30 ° C).

We generally operate at atmospheric pressure. Of course, pressures higher or lower than atmospheric pressure are not excluded.

The perfluoroalkanesulfonyl fluoride thus obtained can be recovered by any appropriate means, for example by simple decantation. Indeed, the present invention has the advantage of allowing very effective separation of perfluoroalkanesulfonyl fluoride by simple decantation, a phase separation can be observed at the end of the reaction.

The perfluoroalkanesulfonyl fluoride thus obtained can then be brought into contact with at least one amino compound in order to prepare a perfluorosulfonamide. Thus, the present invention finally relates to a process for the preparation of perfluorosulfonamide, characterized in that the perfluoroalkanesulfonyl fluoride obtained according to the process described above is brought into contact with at least one amino compound.

According to a particular operating mode, this step is carried out under anhydrous conditions. This mode makes it possible in particular to obtain perfluorosulfonamides with a linear perfluorinated chain.

In this step, the amino compound is preferably a compound of formula NH3_y (R) _y , in which y represents 1 or 2, R represents a linear or branched CJ-C20 alkyl radical. Preferably, y represents 1. Among the linear or branched C-1-C20 alkyl radical, mention may especially be made of the methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, pentyl and hexyl, heptyl, octyl, nonyl, dodecyl radical , pentadecyl. As regards perfluoroalkanesulfonyl, the perfluoroalkyl radical of C- | -C-i2 as defined above is preferred, more particularly the perfluorohexyl or perfluorooctyl radical.

The following examples illustrate the invention without, however, limiting its scope.

EXAMPLES:

Example 1

a / Preparation of the fluorination reagent

11.1 g (1.1 mole) of triethylamine (N (C2H5) 3) is added to 200 ml of H2θ, the temperature of the medium is maintained between 15 and 20 ° C. Then added in fractions of 15 g 62.7 g (1.1 mole) of ammonium bifluoride (NH4F, HF), the final pH of the medium is between 5.6 and 5.8.

b / fluorination reaction.

A solution of 518 g (1 mole) of C8F17SO2CI in 250 ml of CH2CI2 is added over 15 minutes to the aqueous solution of "NH4 ⁺ F", F "NH ⁺ (C2H5) 3" prepared previously. The temperature of the medium is maintained between 20 and 30 ° C for 60 minutes. The lower phase of the reaction medium which consists of 451 g of

C8F 7SO2F is then recovered by decantation.

Yield: 85-90%.

¹⁹ F NMR characteristics: -CF2-SO2F: d = -111.9 ppm. Boiling point: 155 ° C.

Spectral and physical characteristic identical to that of an authentic sample. Example 2

a / Preparation of the fluorination reagent

To 87.6 g (1.2 mol) of diethylamine (NH (C2H5) 2) dissolved in 150 ml of H2θ, 15 g fractions are added while maintaining a temperature of 15-20 ° C, 68.4 g (1.2 mole) of ammonium bifluoride (NH4F, HF), the final pH of the medium is between 7 and 7.5.

b / fluorination reaction

A solution of 518 g (1 mole) of C8F17SO2CI in 250 ml of CH2CI2 is added over 15 minutes to the aqueous solution of "NH4 ⁺ F ^" , F ^" NH2 ⁺ (C2H5) 2" prepared previously. The temperature of the medium is maintained between 30 and 35 ° C for 90 minutes. The lower phase of the reaction medium which consists of 476 g of

C8F17SO2F is then recovered by decantation.

Yield: 92-95%.

¹⁹ F NMR characteristics: -CF2-SO2F: d = -1 1 1.9 ppm. Boiling point: 155 ° C.

Spectral and physical characteristic identical to that of an authentic sample.

Example 3

al Preparation of fluorination reagent To an aqueous solution containing 1.5 moles of ethylamine (NH2C2H5) are added in portions of 15 g, maintaining a temperature between 5 and 10 ° C, 85.5 g (1.5 moles) of ammonium bifluoride (NH4 ⁺ F-, H ⁺ F-), the final pH of the medium is between 6 and 7.

b / fluorination reaction.

A solution of 518 g (1 mole) of C8F17SO2CI in 250 ml of CH2CI2 is added over 15 minutes to the aqueous solution of "NH4 ⁺ F", F "NH3 ⁺ C2H5" prepared previously. The temperature of the medium is maintained between 45 and 50 ° C for 120 minutes.

The lower phase of the reaction medium which consists of 400 g of C8F 7SO2F is then recovered by decantation.

Yield: 80%.

¹⁹ F NMR characteristics: -CF2-SO2F: d = -111.9 ppm.

Boiling point: 155 ° C.

Spectral and physical characteristic identical to that of an authentic sample.

Example 4

a / Preparation of the fluorination reagent

203.9 g (1.1 mol) of tributylamine (N (C4Hg) 3) is added to 400 ml of H2θ, the temperature of the medium is maintained between 15 and 20 ° C. Then added in fractions of 15 g 62.7 g (1.1 mole) of ammonium bifluoride (NH4F, HF), the final pH of the medium is between 6 and 7.

b / fluorination reaction A solution of 518 g (1 mole) of C8F17SO2CI in 250 ml of CH2CI2 is added over 15 minutes to the aqueous solution of "NH4F, NH (C2H5) 3F" prepared previously. The temperature of the medium is maintained at 20 ° C for 60 minutes. The lower phase of the reaction medium which consists of 451 g of

C8F17SO2F is then recovered by decantation.

Yield: 85-90%.

^{1 9} F NMR characteristics: -CF2-SO2F: d = -1 1 1.9 ppm. Boiling point: 155 ° C.

Spectral and physical characteristic identical to that of an authentic sample.

Example 5

Preparation of 1,1,2,2,3,3,4,4,4,5,5,6,6,6 tridecafluoro hexane-1 -sulfonyl

The procedure is as in examples 1, 2 and 3 but replacing the fluoride of 1, 1, 2,2,3,3,4,4,5,5,6,6,7,7,8,8,8 heptadecafluoro octane-1-sulfonyl by the fluoride of 1, 1, 2,2,3,3,4,4,5,5,6,6,6 tridecafluoro hexane-1 -sulfonyl.

Yield: 80-95%. 1 ⁹ F NMR characteristics: -CF2-SO2F: d = -111.9 ppm.

Spectral and physical characteristic identical to that of an authentic sample.

Example 6 Preparation of n-perfluoroalkanesulfonyl fluorides (C8E17SO2F and CfiFiaSOgF) in other solvents.

The procedure is as in the previous examples with the fluorinating agent, the mixtures consisting of an amine and ammonium bifluoride

(NH2C2H5 / NH4F, HF or NH (C2H5) 2 NH4F, HF or N (C2H5.3 / H4F, HF) in different solvents such as methylisobutylketone or sulfolane, in this case, the yields vary from 70 to 85%.

Example 7

Preparation of N-hexyl 1,1,2,2,3,3,4.4,5.5,6,6,7,7,8,8,8,8 heptadecafluoro octane-1 -sulfonamide

At 103 g (0.2 M) of fluoride of 1, 1, 2,2,3,3,4,4,5,5,6,6,7,7,8,8,8 heptadecafluoro hexane-1 - anhydrous sulfonyl, 106 g (0.4 M) of anhydrous hexylamine are added.

The reaction temperature is maintained at 50 ° C for 1/2 hour, with stirring and protected from ambient humidity. At the end of the reaction, crystals appear in the reaction medium. Maintaining the medium at the same temperature, the product is dissolved in 200 ml of ethyl acetate.

After washing the organic phase with 100 ml of 2N aqueous HCl solution, the solvent is distilled under reduced pressure; 1 16 g of crystals are obtained (purity

95%). The product is then purified by crystallization from a mixture of solvent: dichloromethane / methanol (80/20, v / v).

Yield: 90%.

¹⁹ F NMR characteristics: -CF2-SO2NR: d = -1 1 1.9.9 ppm. ¹ H NMR: d ppm 0.85 (t, 3H -CH3), 1, 3 (m, 6H (CH2) 3), 1, 6 (m, 2H -CH2), 3.3 (t, 2H CH2- NH).

Melting point = 88 ° C. Example 8

Preparation of N-octyl 1,1,2,2,3,3,4,4,5,5,6,6,6 heptadecafluoro octane-1 -sulfonamide

The procedure is as in the previous example, replacing the hexylamine with 106 g (0.4 M) of octylamine. 122 g of crystals are obtained (purity 95%).

The product is then purified by crystallization from a mixture of solvent: dichloromethane / methanol (80/20, v / v).

Yield: 90%.

⁹ F NMR characteristics: -CF2-SO2NR: d = -1 11.9 ppm. 1 H NMR: d ppm 0.85 (t, 3H -CH3), 1, 3 (m, 10H (CH2) 5), 1, 6 (m, 2H -CH2), 3.3 (t, 2H CH2- NH). Exact mass calculated: 582.0396; exact mass found: 582.0439 (Err- mmu = 4.3) Melting point = 91 ° C.

Example 9

Preparation of N-dodecyl 1,1,2,2,3,3,4,4.5,5,6,6,7,7,8,8,8 heptadecafluoro octane-1 -sulfonamide

To 70 g (0.37 M) of anhydrous dodecylamine is rapidly added 95 g (0.19 M) of n-perfluorooctylsulfonyl fluoride. The reaction temperature is brought to 60 ° C. for 1 hour with stirring and protected from ambient humidity.

At the end of the reaction, crystals appear in the reaction medium. Maintaining the medium at the same temperature, the product is dissolved in 200 ml ethyl acetate. After washing the organic phase with 100 ml of 2N aqueous HCl solution, the solvent is distilled under reduced pressure; 129.2 g of crystals are obtained (purity 95%).

The product is then purified by crystallization from a mixture of solvent: dichloromethane / methanol (70/30, v / v).

Yield: 90%.

¹⁹ F NMR characteristics: -CF2-SO2NR: d = -11 1.9 ppm. 1 H NMR: d ppm 0.85 (t, 3H -CH3), 1, 3 (m, 18H (CH2) 9), 1.6 (m, 2H -CH2), 3.3 (t, 2H CH2-NH ).

Exact mass calculated: 610.0709; exact mass found: 610.0636 (Err-mmu = 7.3)

Melting point = 93.3 ° C.

Example 10

Preparation of N-hexadecyl 1.1.2.2.3.3.4.4.5.5.6,6.7.7,8,8,8 heptadecafluoro octane-1 -sulfonamide

To 243 g (0.4 M) of anhydrous hexadecylamine, 103 g (0.2 M) of n-perfluorooctylsulfonyl fluoride are added. The reaction temperature is brought to 60 ° C, for 1 hour, with stirring and protected from ambient humidity. At the end of the reaction, crystals appear in the reaction medium. By maintaining the reaction medium at the same temperature, the product is dissolved in 400 ml of ethyl acetate. After washing the organic phase with 100 ml of 2N aqueous HCl solution, the solvent is distilled under reduced pressure; 144 g of crystals are obtained (purity 95%).

Yield: 95%. ¹⁹ F NMR characteristics: -CF2-SO2NR: d = -1 1 1.9.9 ppm. ¹ H NMR: d ppm 0.85 (t, 3H -CH3), 1, 3 (m, 26H (CH2) 13), 1.6 (m, 2H -CH2), 3.3 (t, 2H CH2- NH).

Exact mass calculated: 722.1912; exact mass found: 722.1961 (Err- mmu = -4.8)

Melting point = 92.4 ° C.

Example 11

Preparation of N-butyl 1, 1, 2.2,3,3,4,4,5,5,6,6,6 tridecafluoro hexane-1 -sulfonamide

To 103 g (0.2 M) of hexane-1-sulfonyl fluoride 1, 1, 2,2,3,3,4,4,5,5,6,6,6 anhydrous tridecafluoro, 29 is added, 2 g (0.4 M) of anhydrous n-butylamine. The reaction temperature is maintained at 50 ° C for 1/2 hour with stirring and protected from ambient humidity. At the end of the reaction, crystals appear in the reaction medium. Maintaining the medium at the same temperature, the product is dissolved in 200 ml of ethyl acetate. After washing the organic phase with 100 ml of 2N aqueous HCl solution, the solvent is distilled under reduced pressure, 430 g of crystals are obtained (purity 95%).

Yield: 90%.

1 ⁹ F NMR characteristics: -CF2-SO2NR: d = -1 1 1.9 ppm. ¹ H NMR: d ppm 0.85 (t, 3H -CH3), 1, 3 (m, 2H -CH2), 1.6 (m, 2H -CH2), 3.3

(t, 2H CH2-NH). Identification by spectral comparison with an authentic sample.

Claims

1- Composition, characterized in that it comprises at least one amino compound and ammonium bifluoride.

2- Composition according to the preceding claim, characterized in that the amino compound is an amine of formula (I) NH3_ _X (R <|) _X , in which x represents 1, 2 or 3, Rj represents an alkyl radical, saturated or unsaturated, of C ^< | ~ C20 linear, branched or forms a cycle with nitrogen.

3- Composition according to claim 2, characterized in that the amino compound has an alkyl radical of C1-C4 and more particularly the methyl, ethyl, propyl or butyl radical.

4- Composition according to any one of the preceding claims, characterized in that it is an aqueous composition.

5- Composition according to any one of the preceding claims, characterized in that the molar ratio of the amino compound and of ammonium bifluoride is between 0.8 and 1, 2.

6. Composition according to any one of the preceding claims, characterized in that the pH is between 4 and 8.

7- Composition according to the preceding claim, characterized in that the pH is between 5 and 7.5.

8- Use of the composition defined according to any one of the preceding claims as fluorinating agent.

9- Process for the preparation of perfluoroalkanesulfonyl fluoride, characterized in that it comprises the reaction between the composition defined according to any one of claims 1 to 7 and at least one perfluoroalkanesulfonyl halide.

10- Method according to the preceding claim, characterized in that the halides of perfluoroalkanesulfonyl are chosen from iodides, bromides and chlorides of perfluoroalkanesulfonyl.

11- Method according to any one of claims 9 or 10, characterized in that the perfluoroalkanesulfonyl halides are obtained beforehand by bringing the alkali metal salt of the corresponding perfluoroalkane sulfonic acid into contact with at least one halogenating agent , preferably a chlorinating agent.

12- Method according to the preceding claim, characterized in that the step of obtaining perfluoroalkanesulfonyl halides is carried out in a halogenated organic solvent.

13- A method according to any one of claims 9 to 12, characterized in that said reaction between the composition and at least one perfluoroalkanesulfonyl halide is carried out in a two-phase medium.

14- The method of claim 13, characterized in that the solvents used correspond to a mixture of water and at least one organic solvent not soluble in water.

15- Method according to the preceding claim, characterized in that the organic solvent not soluble in water is chosen from methylene or ethylene chloride, 4-methyl-2-pentanone or even chloroform.

16- Method according to one of claims 9 to 15, characterized in that the perfluoroalkanesulfonyl halide and the ammonium bifluoride present in said composition are used in an amount close to stoichiometry. 17- Process for the preparation of perfluoroalkanesulfonamide, characterized in that the perfluoroalkanesulfonyl fluoride obtained according to the process described in one of claims 9 to 16 is brought into contact with at least one amino compound.

18- The method of claim 17, characterized in that this step is carried out under anhydrous conditions.