Fluorine-containing anionic surfactants

Abstract

The purpose of the present invention is to provide a fluorine-containing anionic surfactant having excellent surface tension reduction ability and water solubility due to the use of a fluorine-containing compound composed of a perfluoroalkyl group having at most 6 carbon atoms, which is considered to have low bioaccumulation.　A fluorine-containing compound represented by general formula (1), a method for producing the same, an intermediate for producing the compound, and a surfactant using the compound, method, and intermediate are used. (In formula (1), Rf1, Rf2, and Rf3 are each independently a C1-C6 perfluoroalkyl group, X1, X2, and X3 are each independently a C1-C8 linear alkylene group which may contain an ethereal oxygen atom, and Y is a substituent containing an anionic polar group.)

Description

[Technical Field]

[0001] The present invention relates to a novel fluorine-containing compound, its use as an anionic surfactant, and a synthetic intermediate thereof. [Background technology]

[0002] Fluorine-containing anionic surfactants have an excellent ability to reduce the surface tension of a solution and are therefore used, for example, as leveling agents in paints and coatings, emulsifiers, dispersants, detergents, surface modifiers, etc.

[0003] Until now, compounds containing perfluoroalkyl groups have been used as fluorine-containing anionic surfactants, but compounds containing long-chain perfluoroalkyl groups with eight or more carbon atoms, such as perfluorooctanesulfonic acid (PFOS), have been viewed with concern due to their potential to bioaccumulate and have adverse effects on the environment.

[0004] For this reason, there is a demand for surfactants made from compounds containing short-chain perfluoroalkyl groups, which are considered to have low bioaccumulation potential. However, there is a problem that as the number of carbon atoms in the perfluoroalkyl group decreases, the ability to reduce the surface tension of a solution decreases, and as the number of carbon atoms in the perfluoroalkyl group increases, the ability to reduce surface tension improves but water solubility decreases.

[0005] Improving the water solubility of fluorine-containing anionic surfactants is important from the viewpoint of improving the handleability in aqueous systems, etc. Patent Documents 1 and 2 disclose fluorine-containing anionic surfactants with excellent water solubility. However, their surface tension reducing ability is insufficient, and further improvement is desired. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 4108985 [Patent Document 2] Japanese Patent Application Laid-Open No. 2003-286246 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a novel fluorine-containing compound composed of a short-chain perfluoroalkyl group which is considered to have low bioaccumulation potential, a surfactant containing the same, and a method for producing the fluorine-containing compound. [Means for solving the problem]

[0008] The present inventors have found that surfactants using fluorine-containing compounds composed of short-chain perfluoroalkyl groups shown below exhibit excellent surface tension reducing ability and water solubility, and have completed the present invention.

[0009] That is, the present invention relates to the following fluorine-containing compound, a surfactant containing the same, and a method for producing the fluorine-containing compound. [1] A fluorine-containing compound represented by the following general formula (1): [ka] (In formula (1), Rf 1 , Rf 2 and Rf 3 are each independently a perfluoroalkyl group having 1 to 6 carbon atoms, X 1 , X 2 and X 3 are each independently a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom, Y is a substituent containing an anionic polar group. [2] In the general formula (1), Y is a substituent containing an anionic polar group selected from the group consisting of -CO2M, -SO3M, -OSO3M, -P(=O)(OM)2 and -OP(=O)(OM)2, where M is a hydrogen atom, an alkali metal ion or NR4 +wherein R is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and all R may be the same or different. [3] The fluorine-containing compound according to [1] or [2], In general formula (1), X 1 , X 2 and X 3 are each independently a linear alkylene group having 1 to 4 carbon atoms which may contain an etheric oxygen atom, Fluorine-containing compound. [4] The fluorine-containing compound according to any one of [1] to [3], In general formula (1), X 1 , X 2 and X 3 are all CH2 or all CH2CH2, Fluorine-containing compound. [5] The fluorine-containing compound according to any one of [1] to [4], In general formula (1), Rf 1 , Rf 2 and Rf 3 are all CF3, X 1 , X 2 and X 3 are all CH2, Fluorine-containing compound. [6] The fluorine-containing compound according to any one of [1] to [5], In general formula (1), Y is —CH—O—SO—Na, —CH—O—(CH)—O—SO—Na or —CH—O—(CH)—SO—Na; Fluorine-containing compound. [7] A surfactant comprising the fluorine-containing compound according to any one of the above [1] to [6]. [8] A fluorine-containing compound represented by the following general formula (2): [ka] (In formula (2), Rf1 , Rf 2 and Rf 3 are each independently a perfluoroalkyl group having 1 to 6 carbon atoms, and X 1 , X 2 and X 3 are each independently a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom. [9] A compound represented by the following formula (3): [ka] (In formula (3), P is an acetal protecting group.)

[10] A method for producing a fluorine-containing compound represented by the following general formula (1): A step of reacting an alcohol represented by the following general formula (4) with a compound represented by the following general formula (3) to obtain a compound represented by the following general formula (5): A step of deprotecting a compound represented by the following general formula (5) to obtain a fluorine-containing compound represented by the following general formula (2); The method includes a step of introducing a substituent containing an anionic polar group into a fluorine-containing compound represented by the following general formula (2): A method for producing a fluorine-containing compound. [ka] (In formula (1), Rf 1 , Rf 2 and Rf 3 are each independently a perfluoroalkyl group having 1 to 6 carbon atoms, and X 1 , X 2 and X 3 are each independently a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom, and Y is a substituent containing an anionic polar group. [ka] (In formula (2), Rf 1 , Rf 2 and Rf 3 are each independently a perfluoroalkyl group having 1 to 6 carbon atoms, and X1 , X 2 and X 3 are each independently a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom. [ka] Rf-X-OH (4) (In the formula (4), Rf is a perfluoroalkyl group having 1 to 6 carbon atoms, and X is a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom.) [ka] (In formula (5), Rf 1 , Rf 2 and Rf 3 are each independently a perfluoroalkyl group having 1 to 6 carbon atoms, and X 1 , X 2 and X 3 are each independently a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom, and P is an acetal protecting group.

[0010] The present invention will be described in detail below. In the fluorine-containing compound of the present invention represented by the above general formula (1), Rf 1 , Rf 2 and Rf 3 are each independently preferably a linear or branched perfluoroalkyl group having 1 to 6 carbon atoms, more preferably a linear perfluoroalkyl group having 1 to 6 carbon atoms, even more preferably a linear perfluoroalkyl group having 1 to 4 carbon atoms, and particularly preferably CF3.

[0011] Rf 1 , Rf 2 and Rf 3 may all be the same, may be different from each other, or two of them may be the same and one of them may be different. 1 , Rf 2 and Rf 3However, it is preferable that they are all the same.

[0012] In the fluorine-containing compound represented by the general formula (1) of the present invention, X 1 , X 2 and X 3 are each independently a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom, preferably a linear alkylene group having 1 to 4 carbon atoms which may contain an etheric oxygen atom, and more preferably CH2 or all CH2CH2. Preferred structures include -CH2-, -CH2CH2-, -CH2CH2CH2-, -CH2-O-CH2CH2-, -CH2CH2-O-CH2CH2-, -CH2CH2CH2-O-CH2CH2-, and the like.

[0013] X 1 , X 2 and X 3 may all be the same, may all be different from each other, or two of them may be the same and one of them may be different. 1 , X 2 and X 3 However, it is preferable that they are all the same.

[0014] In the fluorine-containing compound of the present invention represented by general formula (1), Y is a substituent containing an anionic polar group. The anionic polar group is preferably -CO2M, -SO3M, -OSO3M, -P(=O)(OM)2, or -OP(=O)(OM)2, and among these, -SO3M or -OSO3M is more preferred.

[0015] where M is a hydrogen atom, an alkali metal ion, or NR4 + where R is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and all R may be the same or different. + , K. + or NH4 + Among these, Na + is more preferable.

[0016] Further specific examples of Y include -CO2M, -CH2SO3M, -CH2OSO3M, -CH2P(=O)(OM)2, -CH2O-P(=O)(OM)2, -CH2OCH2CH2SO3M, -CH2OCH2CH2OSO3M, -CH2OCH2CH2P(=O)(OM)2, -CH2OCH2CH2O-P(=O)(OM)2, -CH2OCH2CH2CH2SO3M, -CH2OCH2CH2CH2CH2SO3M, etc. Among these, -CH2SO3M or -CH2OSO3M is preferred, and -CH2-O-SO3Na, -CH2-O-(CH2)3-O-SO3Na or -CH2-O-(CH2)3-SO3Na is more preferred.

[0017] The fluorine-containing compound represented by general formula (1) of the present invention can be used as a surfactant. The form of use is not particularly limited, and may be in the form of the compound alone, an aqueous solution, an aqueous dispersion, an organic solvent solution, an organic solvent dispersion, a mixed solution of water and an organic solvent, a mixed solution of two or more organic solvents, a mixed solution of water and two or more organic solvents, an emulsion, a gel, a mixture with wax, etc. The fluorine-containing compound represented by general formula (1) of the present invention has excellent water solubility, and is therefore particularly suitable for use in a medium containing water.

[0018] The uses of the surfactant comprising the fluorine-containing compound represented by general formula (1) of the present invention are not particularly limited, and examples thereof include additives in paints and coating compositions, leveling agents, emulsifiers, dispersants, detergents, surface modifiers, emulsifiers for emulsion polymerization of fluorine-containing polymers, foaming agents, and fire-extinguishing foams.

[0019] When the surfactant made of the fluorine-containing compound of the present invention is used for the above-mentioned purposes, the solvent that can be used is not particularly limited, and an aqueous solution, an organic solvent, etc. can be used. For example, the organic solvent can be an alcohol such as methanol or ethanol, an ester solvent such as ethyl acetate, a ketone solvent such as acetone, an aromatic hydrocarbon solvent such as toluene, or a hydrocarbon solvent such as hexane. When used as an aqueous solution, the pH may be acidic, neutral, or alkaline. The use of these solvents can be appropriately selected depending on the purpose of use.

[0020] When using the surfactant comprising the fluorine-containing compound of the present invention, one type may be used alone, or two or more types may be used in combination.Furthermore, the surfactant may be used in combination with a component other than the surfactant comprising the fluorine-containing compound of the present invention.

[0021] The fluorine-containing compound of the present invention represented by general formula (1) can be produced via intermediates represented by the following general formulas (2) and (3).

[0022] [ka]

[0023] (In formula (2), Rf 1 , Rf 2 and Rf 3 are each independently a perfluoroalkyl group having 1 to 6 carbon atoms, and X 1 , X 2 and X 3 are each independently a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom.

[0024] [ka]

[0025] (In formula (3), P is an acetal protecting group.)

[0026] A preferred method for producing the fluorine-containing compound represented by general formula (1) of the present invention is A step of reacting an alcohol represented by the following general formula (4) with a compound represented by the following general formula (3) to obtain a compound represented by the following general formula (5): A step of deprotecting a compound represented by the following general formula (5) to obtain a fluorine-containing compound represented by the following general formula (2); A step of introducing a substituent containing an anionic polar group into a fluorine-containing compound represented by the following general formula (2): The present invention is characterized by comprising:

[0027] [ka] (In formula (1), Rf 1 , Rf 2 and Rf 3 are each independently a perfluoroalkyl group having 1 to 6 carbon atoms, and X 1 , X 2 and X 3 are each independently a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom, and Y is a substituent containing an anionic polar group.

[0028] [ka] (In formula (2), Rf 1 , Rf 2 and Rf 3 are each independently a perfluoroalkyl group having 1 to 6 carbon atoms, and X 1 , X 2 and X 3 are each independently a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom.

[0029] [ka]

[0030] Rf-X-OH (4)

[0031] (In the formula (4), Rf is a perfluoroalkyl group having 1 to 6 carbon atoms, and X is a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom.)

[0032] [ka]

[0033] (In formula (5), Rf 1 , Rf 2 and Rf 3 are each independently a perfluoroalkyl group having 1 to 6 carbon atoms, and X 1 , X 2 and X 3 are each independently a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom, and P is an acetal protecting group.

[0034] In the compound of the present invention represented by the general formula (3), P is an acetal-based protecting group, of which a tetrahydropyranyl group or an ethoxyethyl group is preferred.

[0035] In the alcohol represented by general formula (4) of the present invention, Rf is preferably a linear or branched perfluoroalkyl group having 1 to 6 carbon atoms, more preferably a linear perfluoroalkyl group having 1 to 6 carbon atoms, and even more preferably a linear perfluoroalkyl group having 1 to 4 carbon atoms.

[0036] X is a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom, and preferred structures include -CH2-, -CH2CH2-, -CH2CH2CH2-, -CH2-O-CH2CH2-, -CH2CH2-O-CH2CH2-, -CH2CH2CH2-O-CH2CH2-, and the like.

[0037] The compound of the present invention represented by general formula (3) can be obtained by acetal-protecting pentaerythritol tribromide by a known method, for example, by reacting pentaerythritol tribromide with dihydropyran or ethyl vinyl ether in the presence of an acid catalyst such as pyridinium p-toluenesulfonate.

[0038] The compound represented by general formula (3) of the present invention can be purified by known methods, such as neutralization, solvent extraction, drying, filtration, concentration, recrystallization, silica gel column chromatography, etc.

[0039] The method for obtaining the compound represented by formula (5) by reacting the alcohol represented by formula (4) with the compound represented by formula (3) is not particularly limited, and for example, a method (Williamson synthesis) can be used in which the compound represented by formula (3) is reacted with the alcohol represented by formula (4) in a solvent in the presence of a base.

[0040] Solvents that can be used in the reaction to obtain the compound represented by formula (5) include (halogenated) hydrocarbon solvents such as hexane, heptane, toluene, dichloromethane, chloroform, etc., ether solvents such as diethyl ether, diisopropyl ether, tetrahydrofuran, dioxane, etc., polar aprotic solvents such as acetonitrile, dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, etc., water, etc. Any solvent that is inert to the reaction can be used. These solvents may be used alone or in combination of two or more.

[0041] The base applicable to the reaction for obtaining the compound represented by formula (5) is not particularly limited, and examples thereof include inorganic bases such as lithium hydride, sodium hydride, potassium hydride, lithium hydroxide, sodium hydroxide, potassium hydroxide, lithium carbonate, sodium carbonate, potassium carbonate, and cesium carbonate; and metal alkoxides such as potassium tert-butoxide. The compound represented by formula (5) can be purified by known methods, such as neutralization, solvent extraction, drying, filtration, concentration, recrystallization, silica gel column chromatography, etc.

[0042] The method for obtaining the fluorine-containing compound represented by formula (2) by deprotecting the compound represented by formula (5) is not particularly limited, and for example, a method of deprotecting in a solvent in the presence of an acid catalyst can be used.

[0043] The solvent applicable to the deprotection to obtain the compound represented by formula (2) is not particularly limited, but alcohols such as methanol, ethanol, isopropyl alcohol, etc., water, etc. can be used.

[0044] The acid catalyst applicable to the deprotection to obtain the compound represented by formula (2) is not particularly limited, but inorganic acids such as hydrochloric acid and sulfuric acid, and organic acids such as p-toluenesulfonic acid and pyridinium p-toluenesulfonate can be used.

[0045] The compound represented by formula (2) can be purified by known methods, such as neutralization, solvent extraction, drying, filtration, concentration, recrystallization, and silica gel column chromatography.

[0046] There is no particular limitation on the method for obtaining a fluorine-containing compound represented by general formula (1) by introducing a substituent containing an anionic polar group into a fluorine-containing compound represented by formula (2).

[0047] For example, the hydroxy group of the fluorine-containing compound represented by formula (2) can be oxidized by a known method, such as using potassium permanganate or Jones reagent, to introduce a -CO2M group.

[0048] Furthermore, for example, a -CH2OSO3M group can be introduced by reacting the fluorine-containing compound represented by formula (2) with SO3, pyridine SO3 complex, chlorosulfuric acid, sulfuric acid, or the like.

[0049] Furthermore, for example, the hydroxy group of the fluorine-containing compound represented by formula (2) can be substituted with a halogen group by a known method, which is then converted into a thiol group, followed by oxidation, thereby introducing a -CH2SO3M group.

[0050] Furthermore, for example, by reacting the fluorine-containing compound represented by formula (2) with phosphoric acid, phosphorus trichloride, or phosphorus oxychloride, a -CH2O-P(=O)(OM)2 group can be introduced.

[0051] Furthermore, for example, the hydroxy group of the fluorine-containing compound represented by formula (2) can be substituted with a halogen group by a known method, leading to a phosphonate ester group, which can then be hydrolyzed to introduce a -CH2P(=O)(OM)2 group.

[0052] Furthermore, for example, by reacting the fluorine-containing compound represented by formula (2) with 1,3-propane sultone or 1,4-butane sultone, a -CH2OCH2CH2CH2SO3M group or a -CH2OCH2CH2CH2CH2SO3M group can be introduced.

[0053] The fluorine-containing compound represented by general formula (1) of the present invention can be purified by known methods, for example, neutralization, solvent extraction, drying, filtration, concentration, recrystallization, decantation, etc., to obtain the target fluorine-containing compound represented by general formula (1). [Effects of the Invention]

[0054] By using the fluorine-containing compound represented by general formula (1) of the present invention, it is possible to provide a surfactant that is composed of a short-chain perfluoroalkyl group, which is considered to have low bioaccumulation potential, and has excellent surface tension reducing ability and water solubility. [Example]

[0055] Examples of the present invention will be described below, but the present invention is not limited to these examples.

[0056] The following equipment was used for the analysis: 1 H-NMR, 19 F-NMR: Bruker AVANCE II 400 GC-MS: Shimadzu GCMS-QP2010 Ultra Surface tension measurement: Kyowa Interface Science automatic surface tension meter DY-300

[0057] Example 1 Synthesis of THP-protected pentaerythritol tribromide (1)

[0058] [ka]

[0059] Under a nitrogen atmosphere, 300 g of toluene (Fujifilm Wako Pure Chemical Industries, Ltd.), 100.00 g of pentaerythritol tribromide (a1) (Tokyo Chemical Industry Co., Ltd., 307.8 mmol), 3.86 g of p-toluenesulfonic acid pyridinium salt (referred to as "PPTS" in the above reaction scheme) (Fujifilm Wako Pure Chemical Industries, Ltd., 15.4 mmol), and 77.69 g of 3,4-dihydro-2H-pyran (a2) (Fujifilm Wako Pure Chemical Industries, Ltd., 923.5 mmol) were charged into a 1 L four-neck flask and reacted at room temperature for 8 hours. The reaction solution was added dropwise to 400 g of 10% aqueous sodium carbonate solution. After removing the aqueous layer, the organic layer was washed twice with 200 g of pure water. The organic layer was concentrated under reduced pressure to obtain 122.00 g of compound (1) as a colorless oil. The yield was 96.9% (molar equivalent, same below).

[0060] The analysis results were as follows: 1 H-NMR (solvent: deuterated chloroform, internal standard: tetramethylsilane) δ (ppm): 4.60 (t, J = 2.8 Hz, 1H, CH), 3.83 (m, 1H, CH), 3.78 (d, 1H, CH), 3.50 (d, 6H, CH), 3.47 (m, 1H, CH), 3.35 (d, 1H, CH), 1.73-1.45 (m, 6H, CH) GC-MS: Calculated value [C 10 H 17 Br3O2+H] + : 407, Actual value: 407

[0061] Example 2 Synthesis of THP-protected pentaerythritol tris(2,2,2-trifluoroethyl) ether (2)

[0062] [ka]

[0063] Under a nitrogen atmosphere, a 2 L four-neck flask was charged with 740 g of dimethyl sulfoxide (ultra-dehydrated (reagent grade), Fujifilm Wako Pure Chemical Industries, Ltd.) and 63.55 g of sodium hydride (oil-based (reagent grade), Fujifilm Wako Pure Chemical Industries, Ltd., 1.589 mol). While cooling in a 20 °C water bath, 146.77 g of 2,2,2-trifluoroethanol (a3) (Tosoh Finechem Co., Ltd., 1.467 mmol) was added dropwise over 30 min using a dropping funnel. The reaction solution was heated to 60 °C, and a mixture of 100.00 g (244.52 mmol) of compound (1) and 100 g of dimethyl sulfoxide (prepared separately) was added dropwise over 15 min. After 18 h of reaction at 60 °C, 500 g of 5% hydrochloric acid was added and the mixture was extracted with 500 g of diisopropyl ether (Fujifilm Wako Pure Chemical Industries, Ltd.). The organic layer was washed twice with 500 g of pure water, and the aqueous layer was discarded. The residue was then concentrated under reduced pressure to obtain 109.86 g of compound (2) as a pale yellow oil in a yield of 96.3%.

[0064] The analysis results were as follows: 1 H-NMR (solvent: deuterated chloroform, internal standard: tetramethylsilane) δ (ppm): 4.56 (t, J = 2.8 Hz, 1H, CH), 3.82 (m, 1H, CH), 3.80 (q, J = 8.8 Hz, 6H, CH), 3.63 (d, 6H, CH), 3.51 (m, 1H, CH), 3.33 (d, 1H, CH), 1.85-1.45 (m, 6H, CH) 19 F-NMR (solvent: deuterated chloroform, internal standard: benzotrifluoride) δ (ppm): -74.85 (t, J = 8.0 Hz, 9F, CF3) GC-MS: Calculated value [C16 H 23 F9O5-H] + :465, Actual value:465

[0065] Example 3 Synthesis of pentaerythritol tris(2,2,2-trifluoroethyl) ether (3)

[0066] [ka]

[0067] A 1-L four-neck flask was charged with 300 g of methanol (Fujifilm Wako Pure Chemical Industries, Ltd.), 100.00 g (214.44 mmol) of compound (2), and 6.80 g of p-toluenesulfonic acid monohydrate (referred to as "p-TsOH" in the above reaction scheme) (Fujifilm Wako Pure Chemical Industries, Ltd., 21.4 mmol), and the mixture was allowed to react at room temperature for 3 hours. The reaction mixture was added dropwise to 300 g of 10% aqueous sodium bicarbonate solution, extracted with 300 g of diisopropyl ether, and the organic layer was washed twice with 300 g of purified water. The organic layer was concentrated under reduced pressure and subjected to precision distillation to obtain 46.88 g of compound (3) as a colorless oil from the fraction at 105-110 °C under 1.0 kPa. The yield was 57.2%.

[0068] The analysis results were as follows: 1 H-NMR (solvent: deuterated chloroform, internal standard: tetramethylsilane) δ (ppm): 3.79 (q, J = 8.8 Hz, 6H, CH), 3.69 (s, 2H, CHOH), 3.63 (s, 6H, CH), 2.06 (s, 1H, OH) 19 F-NMR (solvent: deuterated chloroform, internal standard: benzotrifluoride) δ (ppm): -74.87 (t, J = 8.0 Hz, 9F, CF3) GC-MS: Calculated value [C 11 H 15 F9O4+H] + :383, Actual value:383

[0069] Example 4 Synthesis of sodium pentaerythritol tris(2,2,2-trifluoroethyl) sulfate (4)

[0070] [ka]

[0071] A 100 mL three-neck flask was charged with 20 g of dichloromethane (Fujifilm Wako Pure Chemical Industries, Ltd.) and 4.58 g of SO₃-pyridine complex (referred to as "SO₃·Py" in the above reaction scheme) (Tokyo Chemical Industry Co., Ltd., 28.78 mmol) and cooled to 0°C. A solution of 10.00 g (26.16 mmol) of compound (3) dissolved in 10 g of dichloromethane was added dropwise, and the mixture was allowed to react at room temperature for 1 hour. The reaction solution was added dropwise to 100 g of 5% aqueous sodium bicarbonate solution and concentrated under reduced pressure. 100 g of acetone was added to the concentrated, dried product, and the insoluble matter was filtered. 100 g of toluene was added, and the mixture was concentrated under reduced pressure until the weight was 55 g. The supernatant was removed by decantation, and the resulting viscous oil was dried under vacuum to obtain 9.25 g of compound (4) as a white solid. The yield was 73.0%.

[0072] The analysis results were as follows: 1 H-NMR (solvent: deuterium oxide, internal standard: 2,2,2-trifluoroethanol) δ (ppm): 4.00 (s, 2H, CH2OS), 3.88 (q, J = 9.2 Hz, 6H, CH2), 3.63 (s, 6H, CH2) 19 F-NMR (solvent: deuterium oxide, internal standard: 2,2,2-trifluoroethanol) δ (ppm): -75.40 (t, J = 9.2 Hz, 9F, CF3)

[0073] Example 5 Synthesis of allyl(pentaerythritol tris(2,2,2-trifluoroethyl)) ether (5)

[0074] [ka]

[0075] In a 100 mL three-neck flask, 40 g of tetrahydrofuran (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and potassium tert-butoxide (" in the above reaction formula") were added. t 4.40 g (Tokyo Chemical Industry Co., Ltd., 39.2 mmol) of 4.40 g of (denoted as "BuOK") and 10.00 g (26.16 mmol) of compound (3) were charged and cooled to 0°C. 4.75 g of allyl bromide (Tokyo Chemical Industry Co., Ltd., 39.2 mmol) was added, and the mixture was allowed to react at room temperature for 1 hour. The reaction solution was added dropwise to 60 g of a 10% aqueous ammonium chloride solution, extracted twice with 50 g of diisopropyl ether, and the organic layer was concentrated under reduced pressure. The mixture was then purified by silica gel column chromatography using hexane as a developing solvent to obtain 8.06 g of compound (5) as a colorless liquid. The yield was 73.0%.

[0076] The analysis results were as follows: 1 H-NMR (solvent: deuterated chloroform, internal standard: benzotrifluoride) δ (ppm): 5.94 (m, 1H, CH), 5.33 (m, 1H, CH), 5.21 (m, 1H, CH), 4.00 (tt, J = 4.0 Hz, 1.2 Hz, 2H, CH), 3.85 (q, J = 5.6 Hz, 6H, CH), 3.69 (s, 6H, CH), 3.50 (s, 2H, CH). 19 F-NMR (solvent: deuterated chloroform, internal standard: benzotrifluoride) δ (ppm): -74.96 (t, J = 7.5 Hz, 9F, CF3)

[0077] Example 6 Synthesis of 3-hydroxypropyl(pentaerythritol tris(2,2,2-trifluoroethyl)) ether (6)

[0078] [ka]

[0079] A 100 mL three-neck flask was charged with 5.00 g (11.8 mmol) of compound (5), and 30 mL of 0.5 M 9-borabicyclo[3.3.1]nonane (tetrahydrofuran solution, designated "9-BBN" in the above reaction scheme) (Tokyo Chemical Industry Co., Ltd., 13.0 mmol) was added dropwise. The mixture was then reacted at room temperature for 2 hours. 30 g of purified water was added to the reaction solution, followed by 9.11 g of sodium peroxoborate tetrahydrate (Fujifilm Wako Pure Chemical Industries, Ltd., 59.2 mmol). The mixture was then reacted for 1 hour. 50 g of 20% aqueous ammonium chloride solution was added to the reaction solution, and the mixture was extracted twice with 50 g of diisopropyl ether. The organic layer was then concentrated under reduced pressure. The mixture was then purified by silica gel column chromatography using ethyl acetate / hexane = 4 / 1 (v / v) as a developing solvent to obtain 4.89 g of compound (6) as a colorless liquid. The yield was 93.4%.

[0080] The analysis results were as follows: 1 H-NMR (solvent: deuterated chloroform, internal standard: benzotrifluoride) δ (ppm): 1 H-NMR (solvent: methanol-d4, internal standard: benzotrifluoride) δ (ppm): 3.83 (q, 8.8 Hz, 6H, CH2), 3.79 (t, J = 6.0 Hz, 2H, CH2), 3.65 (s, 6H, CH2), 3.62 (t, J = 6.0 Hz, 2H, CH2), 3.49 (s, 2H, CH2), 2.36 (s, 1H, OH), 1.86 (quin, J = 6.0 Hz, 2H, CH2) 19 F-NMR (solvent: deuterated chloroform, internal standard: benzotrifluoride) δ (ppm): -74.92 (t, J = 7.5 Hz, 9F, CF3)

[0081] Example 7 Synthesis of sodium 3-(pentaerythritoltris(2,2,2-trifluoroethyl))propyl sulfate (7)

[0082] [ka]

[0083] A 100 mL three-neck flask was charged with 5.0 g of dichloromethane (Fujifilm Wako Pure Chemical Industries, Ltd.) and 0.54 g of SO₃-pyridine complex (referred to as "SO₃·Py" in the above reaction scheme) (Tokyo Chemical Industry Co., Ltd., 2.5 mmol) and cooled to 0°C. A solution of 1.00 g (2.27 mmol) of compound (6) dissolved in 2.0 g of dichloromethane was added dropwise, and the mixture was allowed to react at room temperature for 1 hour. The reaction solution was added dropwise to 10 g of 5% aqueous sodium bicarbonate solution and concentrated under reduced pressure. 20 g of acetone was added to the concentrated solid, and the insoluble matter was filtered. 20 g of toluene was added, and the mixture was concentrated under reduced pressure until the weight was 7.0 g. The supernatant was removed by decantation, and the resulting viscous oil was dried under vacuum to obtain 0.43 g of compound (7) as a white wax. The yield was 34%.

[0084] The analysis results were as follows: 1 H-NMR (solvent: methanol-d4, internal standard: benzotrifluoride) δ (ppm): 4.13 (t, 6.4 Hz, 2H, CH2), 3.89 (q, 8.8 Hz, 6H, CH2), 3.64 (s, 6H, CH2), 3.52 (t, J = 6.0 Hz, 2H, CH2), 3.43 (s, 2H, CH2), 1.92 (quin, J = 6.4 Hz, 2H, CH2) 19 F-NMR (solvent: methanol-d4, internal standard: benzotrifluoride) δ (ppm): -75.01 (t, J = 7.5 Hz, 9F, CF3)

[0085] Example 8 Synthesis of sodium 3-(pentaerythritol tris(2,2,2-trifluoroethyl))propanesulfonate (8)

[0086] [ka]

[0087] In a 100 mL three-neck flask, 15 g of tetrahydrofuran (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and potassium tert-butoxide (" in the above reaction scheme") were added. t1.76 g (Tokyo Chemical Industry Co., Ltd., 15.7 mmol) of 1,3-propane sultone (referred to as "BuOK") and 5.00 g (13.1 mmol) of compound (3) were charged and cooled to 0°C. 1.92 g of 1,3-propane sultone (Tokyo Chemical Industry Co., Ltd., 15.7 mmol) was added, and the mixture was reacted at room temperature for 1 hour. The reaction solution was added dropwise to 100 g of 5% aqueous sodium bicarbonate solution and concentrated under reduced pressure. 50 g of acetone was added to the concentrated dry product, and the insoluble matter was filtered off. 500 g of toluene was added, and the mixture was concentrated under reduced pressure until the weight of the mixture reached 20 g. The supernatant was removed by decantation, and the resulting viscous oil was dried under vacuum to obtain 4.10 g of compound (8) as a white solid. The yield was 62.1%.

[0088] The analysis results were as follows: 1 H-NMR (solvent: methanol-d4, internal standard: benzotrifluoride) δ (ppm): 3.91 (q, 8.8 Hz, 6H, CH2), 3.64 (s, 6H, CH2), 3.52 (t, 2.8 Hz, 2H, CH2), 3.43 (s, 2H, CH2), 2.91 (m, 2H, CH2), 2.06 (m, 2H, CH2) 19 F-NMR (solvent: methanol-d4, internal standard: benzotrifluoride) δ (ppm): -75.02 (t, J = 11.8 Hz, 9F, CF3)

[0089] surface tension measurement Example 9 The compound (4) obtained in Example 4 was dissolved in pure water to prepare an aqueous solution of a predetermined concentration, and the surface tension was measured by the Wilhelmy method. The results are shown in Table 1.

[0090] [Table 1]

[0091] Example 10 The same measurements were carried out as in Example 9, except that compound (7) was used instead of compound (4). The results are shown in Table 2.

[0092] [Table 2]

[0093] Example 11 The same measurements were carried out as in Example 9, except that compound (8) was used instead of compound (4). The results are shown in Table 3.

[0094] [Table 3]

[0095] Comparative Example 1 The same measurements were carried out as in Example 9, except that potassium nonafluorobutanesulfonate (compound (i), manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was used instead of compound (4). The results are shown in Table 4.

[0096] [Table 4]

[0097] The results in Tables 1 to 4 show that the fluorine-containing compounds of the present invention, although composed of short-chain perfluoroalkyl groups, have a superior ability to reduce the surface tension of water compared to existing compounds containing short-chain perfluoroalkyl groups and anionic polar groups.

[0098] Example 12 Water solubility evaluation 1 g of the compound (4) obtained in Example (4) and 1 g of pure water were mixed and stirred at room temperature for 30 minutes. The supernatant was filtered through a syringe filter with a pore size of 0.45 μm, and the content of compound (4) in the filtrate was 19 The solubility was calculated by quantitative analysis using F-NMR (solvent: heavy water, internal standard: 2,2,2-trifluoroethanol). The results are shown in Table 5.

[0099] Example 13 The same measurements were carried out using compound (7) instead of compound (4) in Example 12. The results are shown in Table 5.

[0100] Example 14 The same measurements were carried out using compound (8) instead of compound (4) in Example 12. The results are shown in Table 5.

[0101] Comparative Example 2 The same measurements were carried out as in Example 12, except that compound (i) was used instead of compound (4). The results are shown in Table 5.

[0102] [Table 5]

[0103] The results in Table 5 show that the fluorine-containing compounds of the present invention are superior in water solubility to existing compounds containing a perfluoroalkyl group and an anionic polar group. [Industrial Applicability]

[0104] The fluorine-containing compound of the present invention is composed of a short-chain perfluoroalkyl group which is considered to have low bioaccumulation potential, and can be used as a surfactant excellent in surface tension reducing ability and water solubility.

Claims

1. A fluorine-containing compound represented by the following general formula (1): 【Chemical 1】 (In formula (1), Rf １ , Rf ２ and Rf ３ All are CF ３ and X １ , X ２ and X ３ are each independently a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom, Y is -CO2M, -CH2SO3M, -CH2OSO3M, -CH2P(=O)(OM)2, -CH2O-P(=O)(OM)2, -CH2OCH2CH2SO3M, -CH2OCH2CH 2 OSO 3 M, -CH 2 OCH 2 CH 2 P(=O)(OM) 2 , -CH 2 OCH 2 CH 2 OP(=O) (OM) 2 , -CH 2 OCH 2 CH 2 CH 2 SO 3 M, -CH 2 OCH 2 CH 2 CH 2 CH 2 O-SO 3 M, or -CH 2 -O-(CH 2 ) 3 -O-SO 3 Na, where M is a hydrogen atom or an alkali metal ion.

2. In general formula (1), X １ , X ２ and X ３ are each independently a linear alkylene group having 1 to 4 carbon atoms which may contain an etheric oxygen atom; The fluorine-containing compound according to claim 1.

3. In general formula (1), X １ , X ２ and X ３ are all CH ２ Or all CH ２ CH ２ That is, The fluorine-containing compound according to claim 1 or 2.

4. In general formula (1), Rf １ , Rf ２ and Rf ３ All are CF ３ and X １ , X ２ and X ３ are all CH ２ That is, The fluorine-containing compound according to any one of claims 1 to 3.

5. In general formula (1), Y is -CH ２ -O-SO ３ Na, -CH ２ -O-(CH ２ ) ３ -O-SO ３ Na or -CH ２ -O-(CH ２ ) ３ -SO ３ Na, The fluorine-containing compound according to any one of claims 1 to 4.

6. A surfactant comprising a fluorine-containing compound represented by the following general formula (1): 【Chemistry 2】 (In formula (1), Rf １ , Rf ２ and Rf ３ All are CF ３ and X １ , X ２ and X ３ are each independently a linear alkylene group having 1 to 8 carbon atoms which may contain an etheric oxygen atom, Y is -CO2M, -CH2SO3M, -CH2OSO3M, -CH2P(=O)(OM)2, -CH2O-P(=O)(OM)2, -CH2OCH2CH2SO3M, -CH2OCH2CH 2 OSO 3 M, -CH 2 OCH 2 CH 2 P(=O)(OM) 2 , -CH 2 OCH 2 CH 2 OP(=O) (OM) 2 , -CH 2 OCH 2 CH 2 CH 2 SO 3 M, -CH 2 OCH 2 CH 2 CH 2 CH 2 O-SO 3 M, or -CH 2 -O-(CH 2 ) 3 -O-SO 3 Na, where M is a hydrogen atom or an alkali metal ion.

Images