JP4937530B2 - Fluorine-containing compound and method for producing the same - Google Patents

Description

  The present invention relates to a fluorine-containing compound useful as a synthetic intermediate for fluorine-containing surfactants and fluorine-containing monomers, etc., and a fluorine-containing compound in which two various alcohol residues are introduced into a highly branched fluorocarbon, and It relates to the manufacturing method.

  In general, a fluorocarbon chain is introduced into a molecule of the compound as a useful method for imparting properties such as water / oil repellency, anti-adhesion properties, chemical resistance, flame retardancy and insulating properties to the compound to be modified. A method is known, and the method is widely used in various fields such as surfactants, electric and electronic parts, paints, surface treatment agents and multifunctional synthetic resins.

  As the fluorocarbon chain introducing agent, perfluorocarbon, especially branched fluorocarbon, is considered to be particularly effective because it provides a high reforming effect. In this case, the hexafluoropropene trimer that is not only relatively inexpensive as a fluorine-containing compound but also has a high degree of branching is a kind of fluorocarbon chain introducing agent or a preparation raw material that is extremely useful in practice.

  In this field, in order to enable wider use of such a perfluoropropene trimer, a high functionality modifier is introduced by introducing a plurality of other functional groups into the fluorocarbon chain of the trimer. There is a need for technology to develop

  Non-patent document 1 is known as a prior art document related to such a request. This non-patent document describes that an acetal-type disubstituted product can be obtained by reacting the trimer with phenol in the presence of sodium phenoxide. However, this type of disubstituted product has a drawback in that it does not exhibit sufficient reactivity in the subsequent modification reaction or perfluorocarbon chain introduction reaction due to steric hindrance of the phenyl group constituting the ether bond.

As a solution for such difficulties, a method of reacting a compound having an alcoholic hydroxyl group (alcohol) with the trimer instead of the phenolic hydroxyl group is conceivable.
However, in general, alcohol shows high reactivity with respect to the trimer as compared with phenol because of the small steric hindrance at the reaction point. For this reason, when the alcohol is reacted with hexafluoropropene trimer having three reactive sites under the conditions in which an acetal type disubstituted product is generated, the reaction system becomes complicated and the target 2 In addition to the substitution product, a 3-substitution product is also produced, and there is a problem that the 2-substitution product cannot be obtained efficiently.
The Journal of Chemical Society of Japan, 1978, No.2, pp.253-258

  The object of the present invention is to provide a novel disubstituted product via the alcoholic hydroxyl group of perfluoro-3- (1-methylethyl) -4-methyl-2-pentene corresponding to the major trimer of hexafluoropropene and It is to provide an efficient production method of the disubstituted product.

［式中、Ｒ_１及びＲ_２は、相互に独立して水素原子、炭素原子数が１〜１００の飽和若しくは不飽和脂肪族炭化水素基（該脂肪族炭化水素基は所望によりハロゲン原子、エーテル結合、エステル結合、アミド結合又はアリール基を有していてもよい。）又はアリール基を示す。）］ That is, the present invention relates to a fluorine-containing compound represented by the following general formula (1):

[Wherein, R ₁ and R ₂ are each independently a hydrogen atom, a saturated or unsaturated aliphatic hydrocarbon group having 1 to 100 carbon atoms (the aliphatic hydrocarbon group is optionally a halogen atom, an ether A bond, an ester bond, an amide bond or an aryl group.) Or an aryl group. ]]

In the above general formula (1), R ₁ and R ₂ are each independently a hydrogen atom, a saturated or unsaturated aliphatic carbonization having 1 to 100 carbon atoms, preferably 1 to 50 carbon atoms, particularly 1 to 20 carbon atoms. A hydrogen group or an aryl group is shown.

  Preferred examples of the saturated aliphatic hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, and an undecyl group. A methyl group and an ethyl group are preferred.

  Preferred examples of the unsaturated aliphatic hydrocarbon group include an allyl group, a methallyl group, a crotyl group, a prenyl group, and a propargyl group.

  Preferred aryl groups include phenyl group, tolyl group, xylyl group, naphthyl group and the like.

  The above aliphatic hydrocarbon group may be a halogen atom (for example, a chlorine atom, a bromine atom and an iodine atom) or an ether bond (for example, an alkylene oxide group such as an ethylene oxide group, a propylene oxide group and a butylene oxide group). Ether bonds, etc.), ester bonds (eg, ester bonds of carboxylates such as acetate groups, propionate groups and butyrate groups), amide bonds or aryl groups (eg, phenyl groups, toluyl groups, naphthyl groups, etc.) May be.

（式中、Ｒ_１及びＲ_２の意義は、前記の一般式（１）の場合と同様である。） The present invention also relates to a method for producing a fluorine-containing compound represented by the general formula (1).
The production method includes perfluoro-3- (1-methylethyl) -4-methyl-2-pentene and an excess amount of alcohol represented by the following general formula (2), a protic solvent or an aprotic polar solvent. In which the reaction is carried out in the presence of an alkali metal alkoxide catalyst or an alkali carbonate catalyst.

(In the formula, the meanings of R ₁ and R ₂ are the same as those in the general formula (1).)

  A particularly preferred embodiment of the above method for producing a fluorine-containing compound is that an amount of alcohol (2) of 2 equivalents or more is aprotic with respect to perfluoro-3- (1-methylethyl) -4-methyl-2-pentene. A method of reacting in a polar solvent in the presence of an alkali metal alkoxide base, and using an excess amount of alcohol (2) as a reaction solvent, perfluoro-3- (1-methylethyl) -4-methyl-2- In this method, pentene and the alcohol are reacted in the presence of an alkali metal alkoxide catalyst.

  Perfluoro-3- (1-methylethyl) -4-methyl-2-pentene used in the above reaction is usually easy to prepare as a trimer by oligomerization of hexafluoropropene.

  The hexafluoropropene trimer is represented by the following formula (4) in addition to perfluoro-3- (1-methylethyl) -4-methyl-2-pentene represented by the following formula (3). Perfluoro-2,4-dimethyl-3-heptene and perfluoro-3-ethyl-2,4-dimethyl-2-pentene represented by the following formula (5) are known. In the oligomerization, the compounds (3) and (5) are mainly produced as trimers, and the compound (4) cannot be obtained.

Preferred alcohols represented by the general formula (2) include the following compounds:
CH ₃ (CH ₂ ) _n OH (where n represents a number from 0 to 11), CH ₃ (OCH ₂ CH ₂ ) _n OH (where n represents a number from 1 to 22), XCH ₂ (CH ₂ ) _n OH (wherein n represents a number of 1 to 4, X represents a chlorine atom, bromine atom or iodine atom), XCH ₂ (CH ₂ CH ₂ O) _n OH (formula In the formula, n represents a number of 1 to 4, and X represents a chlorine atom, a bromine atom or an iodine atom.), CH ₂ ═CH ₂ CH ₂ OH, CH ₃ CH═CH ₂ OH, (CH ₃ ) ₂ C _{= CH 2 OH, CH 2 =} CH (CH 3) CH 2 OH, C 6 H 5 CH 2 OH, C 6 H 5 CH 2 CH 2 OH, CF 3 (CF 2) n CH 2 OH ( in wherein, n Represents a number from 0 to 10.), (CH ₃ ) ₂ CHOH, and CH ₂ = CH ₂ CH (CH ₃ ). OH.

  The general amount of alcohol (2) used is 3 to 20 mol, preferably 4 to 6 mol, per mol of perfluoro-3- (1-methylethyl) -4-methyl-2-pentene. When the amount is less than 3 mol, a trisubstituted compound is formed, and the selectivity of the disubstituted product is lowered. On the other hand, if it exceeds 20 mol, the reaction is not affected, but it is not practical.

  Preferred examples of the protic solvent include methanol, ethanol, propanol, allyl alcohol, benzyl alcohol and phenethyl alcohol, with methanol and ethanol being particularly preferred.

  Preferred aprotic polar solvents include tetrahydrofuran, diethyl ether, dimethoxyethane, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide or any mixture thereof, Tetrahydrofuran is particularly preferable.

Preferable alkali metal alkoxide catalysts include potassium t-butoxide, sodium t-butoxide and the like, and preferable alkali carbonates include potassium carbonate, cesium carbonate and the like.
A particularly preferred catalyst for reacting an excessive amount of alcohol (2) with perfluoro-3- (1-methylethyl) -4-methyl-2-pentene in an aprotic polar solvent is potassium t. A particularly preferred catalyst for the reaction using butoxide and the alcohol (2) to be reacted as a reaction solvent is sodium alkoxide or potassium alkoxide corresponding to the alcohol.

  The amount of alkali metal alkoxide catalyst or alkali carbonate used depends on the type of reaction solvent used and is not particularly limited. For example, perfluoro-3- (1-methylethyl) -4-methyl-2-pentene On the other hand, when an excessive amount of alcohol (2) is reacted in an aprotic polar solvent, 2 mol per mole of perfluoro-3- (1-methylethyl) -4-methyl-2-pentene 0.0 to 2.6 mol, preferably 2.2 to 2.4 mol, and perfluoro-3- (1-methylethyl) -4- with an excessive amount of the alcohol to be reacted (2) as a reaction solvent. In the case of reacting methyl-2-pentene with the alcohol, 2.0 to 4.0 moles, preferably 1 mole per mole of perfluoro-3- (1-methylethyl) -4-methyl-2-pentene. The municipal district is 2.2 to 2.6 mol.

  Generally, when the amount of these catalysts used is less than the above range, the reaction does not proceed sufficiently and monosubstituted compounds are also produced. On the other hand, if the amount is larger than the above range, a tri-substituted compound is formed when the reaction is carried out using an aprotic polar solvent.

  The temperature of the reaction is usually −20 ° C. to + 80 ° C., preferably 0 ° C. to 30 ° C. If the temperature is lower than −20 ° C., a sufficient reaction rate cannot be obtained. Moreover, when it becomes higher than +80 degreeC, a reaction system will become complicated and a yield will fall.

  The reaction time depends on the above-mentioned reaction components, the type of catalyst, the reaction temperature and the like, but is usually 0.5 hours to 24 hours, preferably 1 hour to 4 hours.

Hereinafter, the present invention will be described by way of examples.
Example 1
100 g of methanol was placed in a four-necked flask (200 ml) equipped with a dropping funnel, and 13.4 g (120 mmol) of potassium t-butoxide was added and dissolved while stirring at an ice bath temperature (5 ° C.). It was. 22.5 g (50 mmol) of hexafluoropropene trimer [mixture of the compound containing 34% of the above compound (3) and compound (5)] was put in the dropping funnel, and this was put into the above solution in an ice bath. While stirring at a temperature (5 ° C.), the solution was gradually added dropwise over about 30 minutes. After completion of the dropwise addition, stirring was further continued for 2 hours at an ice bath temperature (5 ° C.), and then the reaction was stopped by adding 20 ml of 1N hydrochloric acid to the reaction mixture.
The reaction mixture was transferred into a 300 ml beaker and then subjected to a washing treatment using 100 ml of water three times to obtain 21.4 g of a crude product (yield: 90%). By subjecting this crude product to vacuum distillation, 19.2 g of a compound represented by the following formula (6) was obtained (yield: 81%). The compound contains 15% of an isomer represented by the following formula (7).

The physical properties of the compound (6) and the compound (7) are shown in Table 1 below.

Example 2
500 g of ethanol was put into a four-necked flask (1000 ml) equipped with a dropping funnel, and 123.2 g (1.1 mol) of potassium tert-butoxide was added and dissolved while stirring at an ice bath temperature (5 ° C.). I let you. 225 g (0.5 mol) of hexafluoropropene trimer [mixture of the above compound containing 34% of the above compound (3) and compound (5)] was placed in the dropping funnel, and this was put into the solution under ice bath temperature. While stirring at (5 ° C.), the solution was gradually added dropwise over about 2 hours. After completion of the dropwise addition, stirring was further continued for 2 hours at an ice bath temperature (5 ° C.), and then the reaction was stopped by adding 100 ml of 1N hydrochloric acid to the reaction mixture.
The reaction mixture was transferred into a 3 liter beaker and then subjected to a washing treatment using 1000 ml of water three times to obtain 241 g of a crude product (yield: 96%). The crude product was subjected to vacuum distillation to obtain 196 g of a purified compound represented by the following formula (8) (yield: 78%). The purified compound contains 3% and 7% of a compound represented by the following formula (9) and a compound estimated to be represented by the formula (10), respectively.

The physical properties of the compound (8) and the compound (9) are shown in Table 2 below.

Example 3
In a three-necked flask (100 ml) equipped with a dropping funnel, hexafluoropropene trimer [a mixture of the compound containing 34% of the compound (3) and the compound (5)] 9.00 g (20 mmol), 7.20 g (80 mmol) of ethoxyethanol and 20 g of tetrahydrofuran were added. On the other hand, a solution prepared by dissolving 5.38 g (48 mmol) of potassium t-butoxide in 20 g of tetrahydrofuran was placed in a dropping funnel, and the solution was stirred into the contents of the flask at an ice bath temperature (5 ° C.). The solution was gradually added dropwise over about 30 minutes. After completion of the dropwise addition, stirring was continued for 3 hours under an ice bath temperature (5 ° C.), and the reaction was stopped by adding 8 ml of 1N hydrochloric acid to the reaction mixture.
The reaction mixture was transferred into a 200 ml beaker and then subjected to washing treatment with 50 ml of water three times to obtain 9.02 g of a crude product represented by the following formula (11) (yield: 76%). ). This crude product contains 11% and 6% of a compound represented by the following formula (12) and a compound estimated to be represented by the following formula (13), respectively.

The physical properties of the compound (11) and the compound (12) are shown in Table 3 below.

The novel fluorine-containing compounds according to the present invention are useful as synthetic intermediates such as fluorine-containing surfactants and fluorine-containing monomers. A fluorine-containing compound having 8 to 50 alkylene oxide groups in the molecule is useful as a fluorine-containing surfactant by itself.

Claims (8)

Perfluoro-3- (1-methylethyl) -4-methyl-2-pentene and an excessive amount of alcohol represented by the following general formula (2) are mixed with an alkali metal in a protic solvent or an aprotic polar solvent. The method for producing a fluorine-containing compound represented by the following general formula (1), wherein the reaction is carried out in the presence of an alkoxide catalyst or an alkali carbonate catalyst:

[Wherein, R ₁ and R ₂ are each independently a hydrogen atom, a saturated or unsaturated aliphatic hydrocarbon group having 1 to 100 carbon atoms (the aliphatic hydrocarbon group is optionally a halogen atom, an ether A bond, an ester bond, an amide bond or an aryl group.) Or an aryl group. ]]
R ₂ R ₁ CHOH (2)
[Wherein, R ₁ and R ₂ are as defined above. ] The method according to claim 1 , wherein the protic solvent is a solvent selected from methanol, ethanol, propanol, allyl alcohol, benzyl alcohol and phenethyl alcohol. A solvent in which the aprotic polar solvent is selected from the group consisting of tetrahydrofuran, diethyl ether, dimethoxyethane, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide or any mixture thereof The method according to claim 1 or 2 . The method according to any one of claims 1 to 3 , wherein the alkali metal alkoxide catalyst is potassium t-butoxide or sodium t-butoxide. The method according to any one of claims 1 to 4 , wherein the alkali carbonate is potassium carbonate or cesium carbonate. An alkali metal alkoxide catalyst or alkali carbonate, relative to perfluoro-3- (1-methylethyl) -4-methyl-2-pentene to 1 mole, any claims 1 to 5 2.0 to 2.6 moles The method of crab. The method according to any one of claims 1 to 6 , wherein the alcohol is used in an amount of 3 to 20 mol per mol of perfluoro-3- (1-methylethyl) -4-methyl-2-pentene. The method according to any one of claims 1 to 7 , wherein the reaction is carried out at a temperature of -20 ° C to + 80 ° C.