JPH06306006A - Fluorine-containing unsaturated carbonyl compound and production thereof - Google Patents

Abstract

PURPOSE:To provide a novel fluorine-containing unsaturated carbonyl compound useful as a polymerization initiator, etc., for getting a fluoropolyether polymer having different functionalities at both terminalse CONSTITUTION:The compound of formula I [R is F or group of formula II ((n) is 0-10)], e.g. 2,2-dichloro-3-butenoic acid fluoride. A compound of formula I wherein R is group of formula II can be produced by reacting a dichloroallylzinc reagent of formula III (X is Br, I or CF2CH=CH2) with an acid fluoride of formula IV. A fluoropolyether of formula V ((m) is 0-100) having different functionalities at both terminals can be produced by polymerizing hexachloropropylene oxide using the compound of formula I as a polymerization initiator. The polyether is extremely useful as a functional fluorine-containing vinyl monomer or a precursor for a functional fluorine-containing organic silicon compound.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel fluorine-containing unsaturated carbonyl compound useful as a polymerization initiator or the like for obtaining a fluoropolyether polymer having different functionalities at both ends and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally known carbonyl compounds having an unsaturated group and a fluorine-containing group at the terminal have been reported, for example, those represented by the following formulas (4) and (5).

CH ₂ ═CH—CO—CF ₃ (4) [See J. Fluorine Chem., 20 , 301 (1982)] CH ₂ ═CH—CH ₂ —CO—CF ₃ (5) [J. Org. , 23 , 1396 (1958)]

However, among such carbonyl compounds, for example, the following formula (6): CH ₂ ═CH—CF ₂ —CO—Rf [In the formula, Rf may contain a fluorine atom or an ether bond. Is a fluoroalkyl group,], a ketone or acid fluoride of the type in which a fluorine atom or a perfluoroalkyl group is bonded to carbon atoms directly bonded to both sides of a carbonyl group is not yet known. Not not.

By the way, it is considered that the difluoroallylation reagent is effective for producing the compound represented by the above formula (6). As a similar example, a reaction formula (7) ) To (9) have been reported. (In the formulas below, Me is a methyl group and Ph is a phenyl group.)

Li [CH ₂ CHCF ₂ ] + ClCH ₂ COOMe → CH ₂ ═CHCF ₂ —CO—CH ₂ Cl (7) [See J. Am. Chem. Soc., 105, 4634 (1983)]

CH ₂ ═CHCF ₂ SiMe ₂ Ph + PhCHO → CH ₂ ═CHCF ₂ CH (Ph) -OH (8) [see J. Am. Chem. Soc., 107, 4085 (1985)]

[0008]

[Chemical 4] [See J. Org. Chem., 56 , 1037 (1991)]

[0009]

However, in the reaction of the above formula (7), since the lithium compound used as a reaction component is stable only at a low temperature of -95 ° C or lower, its handling is extremely difficult, Further, as for the product, a fluorine atom is bonded only to the carbon atom on one side of the carbonyl group, but a product having a fluorine atom or the like bonded on both sides cannot be obtained. Also (8) and (9)
No ketone or acid fluoride is produced in the reaction of the formula.

Therefore, an object of the present invention is to provide a novel fluorine-containing unsaturated carbonyl compound having a molecular structure in which a fluorine atom or a perfluoroalkyl group is bonded to carbon atoms on both sides of a carbonyl group, and a method for producing the same. It is in.

[0011]

According to the present invention, the following general formula (1): CH ₂ ═CHCF ₂ —CO—R (1) wherein R is a fluorine atom or the following formula (1a):

[Chemical 5] A fluorine-containing unsaturated carbonyl compound represented by the formula (wherein n is an integer of 0 to 10) is provided.

In the above general formula (1), R is (1a)
The compound (ketone) which is a fluorine-containing group of the formula has the following general formula (2): CH ₂ ═CHCF ₂ ZnX (2), wherein X represents Br, I or —CF ₂ CH═CH _2. The difluoroallyl zinc reagent represented by the following general formula (3):

[Chemical 6] In the formula, n represents an integer of 0 to 10, and is produced by reacting with an acid fluoride represented by

Further, in the general formula (1), the compound (acid fluoride) in which R is a fluorine atom is chlorinated from 2,2-difluorobutenoic acid to synthesize a chloride of the butenoic acid, and then fluorinated. It is manufactured by

[0014]

The fluorine-containing unsaturated carbonyl compound of the present invention represented by the general formula (1) has a molecular structure related to the fact that a fluorine atom or a fluorine-containing group is bonded to carbon atoms on both sides of the carbonyl group. It has an advantage not found in conventionally known fluorine-containing unsaturated carbonyl compounds, that is, the reactivity of the carbonyl group therein is extremely high and other fluorine-containing unsaturated compounds can be easily derived. For example, when hexafluoropropylene oxide (HFPO) is polymerized using the fluorine-containing unsaturated carbonyl compound of the present invention as a polymerization initiator, the following general formula (10):

[0015]

[Chemical 7]

In the formula, m is 0 to 100 and n is an integer of 0 to 10, and a fluoropolyether having heterofunctional groups at both terminals can be obtained. This polyether is extremely useful as a functional fluorine-containing vinyl monomer or a precursor of a functional fluorine-containing organosilicon compound.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Fluorine-containing unsaturated ketone In the fluorine-containing unsaturated carbonyl compound of the present invention represented by the general formula (1), R is a fluorine-containing group of the formula (1a) (hereinafter, fluorine-containing group). Unsaturated ketone) can be synthesized by reacting the difluoroallyl zinc reagent of formula (2) with the acid fluoride of formula (3),
The reaction formula is represented by the following formula, for example.

[0018]

[Chemical 8]

Here, the difluoroallyl zinc reagent of the above formula (2) is prepared by suspending zinc powder in an aprotic polar solvent, and the following halogen compound: CH ₂ ═CHCF ₂ Y (Y is Br or I). , Preferably Br), -50 ° C to 50 ° C, particularly -20 ° C to 10 ° C.
It can be prepared by dropping at a temperature of 15 minutes to 10 hours.

As the aprotic polar solvent used for the preparation of the difluoroallyl zinc reagent, diethyl ether,
Ethers such as THF, dioxane, glyme, diglyme, triglyme and tetraglyme, nitriles such as acetonitrile and adiponitrile, DMF, DMA
Examples thereof include amides such as c and HMPA, and sulfoxides such as DMSO. Of these, diglyme, triglyme, tetraglyme, DMF and DMAc are preferable. The zinc powder suspended in this solvent is preferably activated in advance by a method such as treatment with dilute hydrochloric acid.

The molar ratio of zinc / halogen compound is 0.
It is preferable to set it in the range of 5 to 2, particularly 0.7 to 1.2, and the amount of the aprotic polar solvent used is 0.1 to 10 liters, especially 0.2 to 1 mol of the halogen compound. A ratio of 2 liters is desirable.

After the reaction between the zinc and the halogen compound, the excess zinc can be removed by filtration or separated by collecting the supernatant liquid, whereby a solution of the difluorozinc reagent can be obtained. The resulting difluoroallyl zinc reagent can be confirmed for production by ¹⁹ F-NMR, and at the same time, consumption of the halogen compound as a raw material can be observed. In addition, the concentration of the difluoroallyl zinc reagent was determined by mixing a fixed amount of standard fluorine compound with ¹⁹ F-NM.
It can be calculated by measuring the integral ratio of R.

On the other hand, the acid fluoride of the formula (3) to be reacted with the above-mentioned difluorozinc reagent can be easily obtained by a method known per se, for example, by polymerizing HFPO.

In producing the fluorine-containing unsaturated ketone of the present invention, the reaction between the difluorozinc reagent of the formula (2) and the acid fluoride of the formula (3) is carried out at -20 to 30 ° C, particularly -5 to 30 ° C.
It can be easily carried out by mixing and stirring both at a temperature of ° C for 15 minutes to 10 hours.

Since the compatibility of the solvent of the above zinc reagent with the acid fluoride is usually low, the reaction is carried out in a heterogeneous two-layer system. In this case, the progress of the reaction can be confirmed by performing a gas chromatography analysis on the fluorine-containing compound as the lower layer or by performing a ¹⁹ F-NMR analysis on the solvent containing the zinc reagent as the upper layer. After the reaction,
The lower layer can be separated and the target fluorinated unsaturated ketone can be isolated by means such as distillation.

Acid Fluoride Further, the acid fluoride in which R in the general formula (1) is a fluorine atom, that is, 2,2-difluoro-3-butenoic acid fluoride, is 2,2-difluoro-3-butenoic acid. As a raw material, it can be produced by the following synthetic route.

[0027]

In the above synthetic route, butenoic acid (2,
The synthesis of butenoic acid chloride from 2-difluoro-3-butenoic acid) is carried out by reacting the butenoic acid with a chlorinating agent. The chlorinating agent to be used is not particularly limited, and thionyl chloride, phosphorus pentachloride and the like can be used, but thionyl chloride is preferably used because the aftertreatment of the by-product is easy. The chlorinating agent is
It is usually used in an amount of 1.1 to 1.5 times the molar amount of butenoic acid to be chlorinated.

The reaction between butenoic acid and the chlorinating agent can be carried out by simply mixing the two, but in order to proceed the reaction safely and smoothly, the chlorinating agent is dropped into butenoic acid. It is preferable. The reaction temperature is 30-80.
C., especially 40 to 60.degree. C. are suitable. If necessary, dimethylformamide (DMF) can be used as a reaction catalyst.

The butenoic acid chloride obtained above (2,
Fluorination of (2-difluoro-3-butenoic acid chloride) is carried out by reacting this with an alkali metal fluoride. As the alkali metal fluoride, sodium fluoride, potassium fluoride, cesium fluoride or the like can be used, and generally, with respect to butenoic acid chloride.
It is used in an amount of 1.1 to 2.5 molar times.

The reaction may be carried out by suspending the metal fluoride in a solvent and dropping the butenoic acid chloride to be fluorinated therein. As the solvent, nitriles such as acetonitrile and adiponitrile, ethers such as diethyl ether, THF and dioxane, and other glymes can be used, and nitriles are particularly preferable. The reaction temperature is 20
To 70 ° C., preferably 30 to 50 ° C. Usually, the desired butenoic acid chloride is synthesized by reacting for 1 to 5 hours, and after completion of the reaction, the target product can be obtained by distillation and isolation. it can.

In the above synthetic route, 2,2-difluoro-3-butenoic acid used as a starting material is, for example, represented by the following formula (11): BrCH ₂ CH ₂ CF ₂ COOEt (11) [wherein Et Is an ethyl group (hereinafter, the same)] is subjected to a HBr-removing reaction in the presence of an alkali, and the Br-substituted fluorine-containing ethyl ester is subjected to the following formula (12): CH ₂ ═CHCF ₂ COOEt (12) It is obtained by synthesizing the ester represented by and further hydrolyzing the ester in an aqueous solution of alkali hydroxide.

The fluorine-containing unsaturated carbonyl compound of the present invention thus obtained is used for homopolymerization, various olefin compounds, in addition to the use of HFPO as a polymerization initiator.
Production of high-molecular polymers by copolymerization with vinyl compounds,
It can be used for modification of a silicon compound by a hydrosilylation reaction with a silicon compound having a SiH bond. Further, since the fluorine-containing unsaturated carbonyl compound of the present invention has high reactivity of the carbonyl group in the molecule, it can easily react with alcohols and amides to form derivatives such as esters and acid amides. In particular, various polymers or compounds derived from the compound of the present invention are expected to have good water repellency, oil repellency, lubricity, and affinity for fluorine materials.

[0034]

EXAMPLES Reference Example 1 A 100 ml three-necked flask equipped with a magnetic stirrer, a dropping funnel, a thermometer and a condenser was charged with 9.8 g (150 mmol) of Zn powder which had been previously activated with dilute hydrochloric acid and sufficiently dried. D was previously dehydrated and distilled by using CaH _2.
MF39.0g was added and stirring was started. Then, the flask was cooled with ice brine, and 15.6 g (99 mmol) of CH ₂ ═CHCF ₂ Br was added dropwise over 50 minutes while continuing vigorous stirring. During this time, heat generated up to 4 ° C
It was seen that the internal temperature increased. After further stirring at 0 ° C. for 1 hour, suction filtration was performed using a glass filter to remove excess Zn powder to obtain 56.8 g of DMF solution. The above operation was always carried out in a stream of dry nitrogen to prevent the entry of water. 1.45 of the obtained DMF solution
0 g was put into an NMR tube, 0.039 g (0.267 mmol) of PhCF ₃ was added and mixed well, and ¹⁹ F-NMR analysis was performed.

In the NMR spectrum, in addition to 12.5 ppm showing the absorption of PhCF ₃ (CF ₃ COOH standard, the same applies hereinafter), only absorption at −21.7 ppm was observed, and CH ₂
= CHCF ₂ Br, there was no absorption at the 27.1 ppm position. This indicates that CH ₂ ═CHCF ₂ Br was completely consumed, and the difluoroallyl zinc reagent represented by the above formula (2) was produced.

In the above NMR spectrum, 1
The integral ratio between the absorption of 2.5ppm and the absorption of -21.7ppm is 1
It was 4.65. From this integration ratio, CH ₂ = 1 contained in the state of the zinc reagent of the formula (2) in 1 g of the DMF solution
The amount of CHCF ₂ -residue was calculated to be 1.28 mmol. Amount of DMF solution obtained and CH ₂ = CH used
Considering the amount of CF ₂ Br, the yield was 73%.

The DMF solution of the difluoroallyl zinc reagent thus obtained was stored in a refrigerator at a predetermined temperature, and the concentration after a certain period of time was measured by ¹⁹ F-NMR. As a result, −
The concentration after 4 days of storage at 20 ° C is 45% of the initial value.
However, the concentration after 13 days at -65 ° C was 8% of the initial value.
It kept 7%.

Example 1 A 500 ml three-necked flask equipped with a magnetic stirrer, a thermometer and a condenser was cooled to 0 ° C., and a DMF solution of a difluoroallyl zinc reagent prepared in Reference Example 1 (concentration:
0.87 mmol / g) was charged in an amount of 160.0 g (139 mmol).

Next, 50.8 g (15) of HFPO dimer acid fluoride represented by the following formula (3a): CF ₃ CF ₂ CF ₂ —O—CF (CF ₃ ) —COF (3a)
3 mmol) was added and vigorous stirring was started. At this time, 20
The temperature was raised to 25 ° C over a period of 2 minutes, and the stirring was continued for 2 hours. Then, the reaction system was separated into two layers, and the upper layer was sampled and subjected to ¹⁹ F-NMR analysis.
Absorption of ppm zinc reagent has disappeared. Also the lower GC
As a result of analysis, in addition to the acid fluoride as the raw material represented by the formula (3a), peaks of main products were observed. The lower layer is separated and distilled to give a boiling point of 72 ° C / 154 mm
22.2 g of Hg product was isolated (41% yield).

¹⁹ F-NMR, ¹ H-N of the obtained product
MR, was subjected to IR and GC-MS analysis, the following formula _{(i): CH 2 = CHCF} 2 -CO-CF (CF 3) has a structure represented by _{OCF 2 CF 2 CF 3 (i} ) Was confirmed. The results of each analysis are as follows.

[0041]¹⁹F-NMR: CF₃COOH standard -59.5ppm (m, 1F, -CO-CF<) -53.0ppm (s, 2F, -O-CF₂-CF ₂-CF₃) −28.9ppm (m, 2F, −CF ₂−CO−) −5.2 to −3.3ppm (m, 8F, −CO−CF (CF ₃ ) −O- CF
₂-CF₂-CF ₃) ¹ H-NMR: TMS standard 5.6 to 6.1 ppm (m, 3H) IR: (chart shown in FIG. 1) 1780 cm^-1(C = O) 1660 cm^-1(C = C) GC-MS: 371 (MF)⁺

Example 2 DMF of difluoroallyl zinc reagent prepared in Reference Example 1
A solution of 50.8 g (65 mmol) and the following formula (3b):

[0043]

[Chemical 9]

54.0 g (65 mmol) of acid fluoride represented by
An experiment was performed in the same manner as in Example 1 except that and were reacted, and 17.7 g of the compound represented by the following formula (ii) was obtained (yield 31%).

[0045]

[Chemical 10]

Example 3 Dry potassium fluoride was placed in a 500 ml four-necked flask equipped with a Dimroth condenser, a dropping funnel, a thermometer and a stirrer.
78.8 g and 147.6 g of dehydrated acetonitrile were charged. Then, with stirring at 25 ° C, 2,2-difluoro-3
-Butenoic acid chloride (104.3 g) was added dropwise using a dropping funnel over about 1 hour. Internal temperature is 50 due to heat generation at the end of dropping
Rose to ℃. Then, stirring was continued for 1 hour to complete the reaction. The reaction mixture obtained is distilled to obtain a fraction having a boiling point of 32 to 37 ° C.
79.6 g (yield: 86%) was obtained.

The analysis results of this fraction are shown below. Infrared absorption spectrum: CaF ₂ gas cell A chart is shown in FIG. Characteristic absorption; 1885cm ^-1 (C = O), 1420cm ^-1 , 1265c
m ^-1 , 1220 cm ^-1 , 1120 cm ^-1 , 1030 cm ^-1

GC-MS: Molecular weight 124 ¹ H-NMR: (TMS standard) 5.9 ppm (m, 3H, CH ₂ = CH-) ¹⁹ F-NMR: (CF ₃ COOH standard) -28.7 ppm (s, CF ₂ , 2F) 94.5ppm (s, COF, 1F)

Elemental analysis: (%) C H F calculated value (%): 38.5 2.6 46.3 Measured value (%): 38.7 2.4 46.0 From the above results, the obtained compound was 2,2-difluoro-3-butene. It was confirmed to be acid fluoride.

[0050]

The fluorine-containing unsaturated carbonyl compound of the present invention has extremely high reactivity and can be easily produced. When this compound is used as an HFPO polymerization initiator, a fluoropolyether polymer having an unsaturated group and an acid fluoride group at both ends and having different functional groups at both ends can be obtained. Further, it can be used for homopolymerization, synthesis of high-molecular polymers by various copolymerizations, and modification of silicon compounds by hydrosilylation with SiH compounds. Furthermore, since the carbonyl group has high reactivity, derivatives such as esters and amides can be easily formed by reaction with various alcohols and amines.

[Brief description of drawings]

FIG. 1 is an IR chart of a fluorine-containing unsaturated ketone synthesized in Example 1.

FIG. 2 is 2,2-difluoro-3-synthesized in Example 3.
The figure which shows a butenoic acid fluoride IR chart.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location // C08F 16/00 MLD 6904-4J 16/36 MLC 6904-4J 299/02 MRS 7442-4J C09D 5/00 PPG 6904-4J PPK 6904-4J C09K 3/18 102 8318-4H (72) Inventor Hiroshi Inomata, Hitotsumi, Matsuida-cho, Usui-gun, Gunma 10 Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory

Claims (3)

[Claims] 1. The following general formula (1): CH ₂ ═CHCF ₂ —CO—R (1) In the formula, R is a fluorine atom or the following formula (1a): (Here, n is an integer of 0 to 10) A fluorine-containing unsaturated carbonyl compound represented by: _2. A difluoroarylzinc reagent represented by the following general formula (2): CH ₂ ═CHCF ₂ ZnX (2), wherein X represents Br, I or —CF ₂ CH═CH ₂ . The following general formula (3): In the formula, n represents an integer of 0 to 10, and is reacted with an acid fluoride represented by the following formula; In formula, n shows the integer of 0-10, The manufacturing method of the fluorine-containing unsaturated ketone represented by these. 3. A method for producing 2,2-difluoro-3-butenoic acid fluoride, characterized by chlorinating 2,2-difluorobutenoic acid to synthesize a chloride of said butenoic acid, and then fluorinating this. .