JP7656161B2 - Method for producing vinyl fluoride compounds - Google Patents

Description

This disclosure relates to a method for producing a vinyl fluoride compound.

When a halogen atom other than the fluorine atom bonded to the SP2 carbon atom in a halogenated vinyl compound is substituted with a fluorine atom, for example, a method of fluorinating the chlorine atom of tetrachloroethylene (PCE) with hydrogen fluoride and boron trifluoride (BF ₃ ) is known (see, for example, Non-Patent Document 1).

Journal of American Chemical Society, 1948, 70 (2), pp 758-760.

The present disclosure aims to provide a method for obtaining vinyl fluoride compounds with high yield and high selectivity.

This disclosure includes the following:

Item 1. General formula (1):
CHR ¹ = CFR ² (1)
[In the formula, ^R1 represents a hydrogen atom, a halogen atom, an alkyl group, or a fluoroalkyl group. ^R2 represents a halogen atom, an alkyl group, or a fluoroalkyl group. However, when ^R2 is a fluoroalkyl group, ^R1 is a halogen atom, an alkyl group, or a fluoroalkyl group.]
A method for producing a vinyl fluoride compound represented by the following formula:
In the presence of an alkali metal fluoride,
General formula (2):
CHR ¹ = CXR ³ (2)
[In the formula, ^R1 represents a hydrogen atom, a halogen atom, an alkyl group or a fluoroalkyl group. ^R3 represents a halogen atom, an alkyl group or a fluoroalkyl group. However, when ^R3 is a fluoroalkyl group, ^R1 is a halogen atom, an alkyl group or a fluoroalkyl group. X represents a halogen atom other than a fluorine atom.]
a reaction step of reacting a vinyl halide compound represented by the general formula (1) to obtain a vinyl fluoride compound represented by the general formula (1).

Item 2. The vinyl fluoride compound represented by the general formula (1) is represented by the general formula (1A):

[In the formula, ^R1 and ^R2 are the same as above.]
Item 2. The method according to item 1, wherein the vinyl fluoride compound is represented by the formula:

Item 3. The halogenated vinyl compound represented by the general formula (2) is represented by the general formula (2A):

[In the formula, R ¹ , R ³ and X are the same as above.]
3. The method according to claim 1 or 2, wherein the vinyl halide compound is represented by the formula:

Item 4. The method according to any one of Items 1 to 3, wherein the alkali metal fluoride has a specific surface area of 500 to 2000 ^{m 2} /g.

Item 5. The method according to any one of items 1 to 4, wherein the alkali metal fluoride is supported on a carrier.

Item 6. The manufacturing method according to Item 5, in which the content of the alkali metal fluoride is 0.1 to 75 mass%, with the total amount of the carrier and the alkali metal fluoride being 100 mass%.

Item 7. The method according to any one of items 1 to 6, wherein the reaction step is carried out in the presence of a fluorine-containing gas.

Item 8. The method according to any one of items 1 to 7, wherein in the reaction step, the contact time (W/F) of the vinyl halide compound with the catalyst containing the alkali metal fluoride is 5 to 200 g·sec/cc.

Item 9. The method according to any one of items 1 to 8, wherein the reaction temperature in the reaction step is 200 to 500°C.

Item 10. General formula (1A):

[In the formula, ^R1 represents a hydrogen atom, a halogen atom, an alkyl group, or a fluoroalkyl group. ^R2 represents a halogen atom, an alkyl group, or a fluoroalkyl group. However, when ^R2 is a fluoroalkyl group, ^R1 is a halogen atom, an alkyl group, or a fluoroalkyl group.]
and a vinyl fluoride compound represented by general formula (3):
^R1- C≡C- ^R2 (3)
[In the formula, ^R1 and ^R2 are the same as above.]
and an alkyne compound represented by the formula:

Item 11. The composition according to item 10, in which the content of the vinyl fluoride compound represented by the general formula (1) is 60 to 99.9 mol % and the content of the alkyne compound represented by the general formula (3) is 0.1 to 20 mol %, with the total amount of the composition being 100 mol %.

Item 12. The vinyl fluoride compound represented by the general formula (1A) is represented by the general formula (1A1):

[In the formula, R ¹ is the same as above.]
and a difluorovinyl compound represented by the formula:
General formula (1A2):

[In the formula, ^R1 is the same as above. ^X1 represents a halogen atom other than a fluorine atom.]
Item 12. The composition according to item 10 or 11, comprising a vinyl fluoride compound represented by the following formula:

Item 13. The composition according to item 12, in which the content of the difluorovinyl compound represented by general formula (1A1) is 40 to 98 mol % and the content of the fluorinated vinyl compound represented by general formula (1A2) is 2 to 30 mol %, with the total amount of the composition being 100 mol %.

Item 14. The composition according to any one of items 10 to 13, which is used as a cleaning gas, an etching gas, a refrigerant, or a building block for organic synthesis.

According to the present disclosure, vinyl fluoride compounds can be obtained with high yield and high selectivity.

In this specification, "containing" is a concept that encompasses all of "comprise," "consist essentially of," and "consist of." In addition, in this specification, when a numerical range is indicated as "A to B," it means A or more and B or less.

In this disclosure, "selectivity" means the ratio (mol %) of the total molar amount of the target compound contained in the effluent gas from the reactor outlet to the total molar amount of compounds other than the raw material compound in the effluent gas.

In this disclosure, "conversion rate" means the ratio (mol %) of the total molar amount of compounds other than the raw material compounds contained in the effluent gas from the reactor outlet to the molar amount of the raw material compounds supplied to the reactor.

In this disclosure, "yield" refers to the ratio (mol %) of the total molar amount of the target compound contained in the effluent gas from the reactor outlet to the molar amount of the raw material compounds supplied to the reactor.

1. Method for Producing a Vinyl Fluoride Compound The method for producing a vinyl fluoride compound according to the present disclosure includes the steps of:
General formula (1):
CHR ¹ = CFR ² (1)
[In the formula, ^R1 represents a hydrogen atom, a halogen atom, an alkyl group, or a fluoroalkyl group. ^R2 represents a halogen atom, an alkyl group, or a fluoroalkyl group. However, when ^R2 is a fluoroalkyl group, ^R1 is a halogen atom, an alkyl group, or a fluoroalkyl group.]
A method for producing a vinyl fluoride compound represented by the following formula:
In the presence of an alkali metal fluoride,
General formula (2):
CHR ¹ = CXR ³ (2)
[In the formula, ^R1 represents a hydrogen atom, a halogen atom, an alkyl group or a fluoroalkyl group. ^R3 represents a halogen atom, an alkyl group or a fluoroalkyl group. However, when ^R3 is a fluoroalkyl group, ^R1 is a halogen atom, an alkyl group or a fluoroalkyl group. X represents a halogen atom other than a fluorine atom.]
The method includes a reaction step of reacting a vinyl halide compound represented by the general formula (1) with the vinyl fluoride compound represented by the general formula (1).

Conventionally, fluorine atoms have been introduced by first performing a hydrogen fluoride addition reaction and then performing a dehydrohalogenation reaction. This method requires two separate reaction steps, and in addition, when performing the dehydrohalogenation reaction, a dehydrofluorination reaction also occurs at the same time, and a large amount of by-products are generated, resulting in low selectivity for the target product. In addition, as shown in Non-Patent Document 1, a method is known in which chlorine atoms are fluorinated in tetrachloroethylene (PCE) using hydrogen fluoride and boron trifluoride (BF ₃ ), but the yield in this case is only about 20%.

According to the present disclosure, as described above, a vinyl halide compound having a halogen atom other than a fluorine atom is used as a substrate, and reacted in the presence of an alkali metal fluoride to obtain a vinyl fluoride compound in a single step with high yield and high selectivity.

(1-1) Vinyl halide compound The vinyl halide compound usable as a substrate in the production method of the present disclosure is represented by the general formula (2):
CHR ¹ = CXR ³ (2)
[In the formula, ^R1 represents a hydrogen atom, a halogen atom, an alkyl group or a fluoroalkyl group. ^R3 represents a halogen atom, an alkyl group or a fluoroalkyl group. However, when ^R3 is a fluoroalkyl group, ^R1 is a halogen atom, an alkyl group or a fluoroalkyl group. X represents a halogen atom other than a fluorine atom.]
It is a vinyl halide compound represented by the formula:

The vinyl halide compound may contain both cis and trans isomers, but the trans isomer is preferred from the viewpoint of producing a vinyl fluoride compound with a particularly high conversion rate, yield and selectivity, and is represented by the general formula (2A):

[In the formula, R ¹ , R ³ and X are the same as above.]
Preferred are vinyl halide compounds represented by the following formula:

In the general formulae (2) and (2A), examples of the halogen atom represented by ^R1 and ^R3 include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

In general formulae (2) and (2A), examples of the alkyl group represented by ^R1 and ^R3 include alkyl groups having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl. These alkyl groups may also have 1 to 6, particularly 1 to 3, substituents such as the above-mentioned halogen atoms.

In general formulae (2) and (2A), examples of the fluoroalkyl group represented by ^R1 and ^R3 include fluoroalkyl groups having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms (particularly perfluoroalkyl groups), such as a trifluoromethyl group and a pentafluoroethyl group.

However, when R ¹ is a hydrogen atom and R ³ is a fluoroalkyl group, the vinyl fluoride compound is not represented by the general formula (1) but by the general formula (3):
^R1- C≡C- ^R2 (3)
[In the formula, ^R1 and ^R2 are the same as above.]
Therefore, when R ³ is a fluoroalkyl group, R ¹ is a halogen atom, an alkyl group, or a fluoroalkyl group.

In general formulas (2) and (2A), examples of the halogen atom represented by X include a chlorine atom, a bromine atom, and an iodine atom.

In terms of the vinyl halide compound substrate, from the viewpoint of producing a vinyl fluoride compound with particularly high conversion rate, yield and selectivity, it is preferable that ^R1 and ^R3 are both fluoroalkyl groups (particularly perfluoroalkyl groups) and X is a chlorine atom.

In addition, when both ^R3 and X are halogen atoms other than fluorine atoms, the reaction of the halogenated vinyl compounds represented by the above general formulas (2) and (2A) produces ^CHR1 = ^CFX1 in which only one halogen atom is substituted with a fluorine atom, particularly the compound represented by the general formula (1A2):

[In the formula, ^R1 is the same as above. ^X1 represents a halogen atom other than the above-mentioned fluorine atom.]
and a vinyl fluoride compound represented by the general formula (1A1) in which two halogen atoms are replaced by fluorine atoms:

[In the formula, R ¹ is the same as above.]
Both the difluorovinyl compound represented by the general formula (1A1) and the vinyl fluoride compound represented by the general formula (1A2) are the target compounds.

The above-mentioned R ¹ , R ³ and X may be the same or different.

Specific examples of vinyl halide compounds that can serve as substrates that satisfy the above conditions include:

These vinyl halide compounds can be used alone or in combination of two or more. Such vinyl halide compounds can be publicly known or commercially available products.

(1-2) Substitution Reaction In the reaction step of reacting a halogenated vinyl compound represented by general formula (2) in the present disclosure, for example, in the halogenated vinyl compound represented by general formula (2) as a substrate, R ¹ and R ³ are both preferably trifluoromethyl groups, X is preferably a chlorine atom, and a trans isomer is preferred. In addition, in the halogenated vinyl compound represented by general formula (2) as a substrate, it is also preferred that R ¹ is a hydrogen atom, and R ³ and X are chlorine atoms.

That is, the reaction equation is as follows:

It is preferable to obtain a vinyl fluoride compound in one step according to the following:

(1-3) Alkali Metal Fluoride The reaction step of reacting the vinyl halide compound represented by the general formula (2) in the present disclosure is a step in which halogen atoms are replaced with fluorine atoms in a single step in the presence of an alkali metal fluoride. The alkali metal fluoride functions as a catalyst, and the vinyl halide compound can be produced with particularly high conversion, yield and selectivity.

The alkali metal fluoride is not particularly limited, but from the viewpoint of being able to produce a vinyl fluoride compound with a particularly high conversion rate, yield, and selectivity, fluorides of alkali metals of the 4th to 7th periods are preferred, for example, potassium fluoride (KF), cesium fluoride (CsF), etc. are more preferred, and cesium fluoride (CsF) is even more preferred. These alkali metal fluorides can be used alone or in combination of two or more kinds.

The specific surface area of the alkali metal fluoride is preferably 500 to 2000 ^{m 2} /g, more preferably 800 to 1500 ^{m 2} /g, from the viewpoint of being able to produce a vinyl fluoride compound with particularly high conversion, yield and selectivity. In the present disclosure, the specific surface area of the alkali metal fluoride is measured by the BET method. When the specific surface area of the alkali metal fluoride is in such a range, the density of the alkali metal fluoride particles is not too small, so that the target compound can be obtained with a higher selectivity. It is also possible to further improve the conversion rate of the substrate. As described later, even when the alkali metal fluoride is supported on a carrier, there is no significant difference in the specific surface area, and the specific surface area when the alkali metal fluoride is supported on a carrier is also preferably in the above-mentioned range.

In the present disclosure, when the reaction is carried out in the gas phase, the above-mentioned substrate is contacted with a fluorine source. In this case, from the viewpoint of reactivity, it is preferable to contact the alkali metal fluoride with the substrate in a solid state (solid phase).

In the present disclosure, for example, when a gas-phase continuous flow reaction is performed, from the viewpoint of reactivity, the alkali metal fluoride may be in a powder form, but is preferably in a pellet form. The above-mentioned alkali metal fluoride may be used as is, but may be supported on a carrier and used (hereinafter, the alkali metal fluoride supported on a carrier may be referred to as "support-supported alkali metal fluoride"). This increases the specific surface area of the fluorine source, improving the reaction efficiency, and making it possible to produce a vinyl fluoride compound with a particularly high conversion rate, yield, and selectivity. There are no particular limitations on the support, and examples of the support include carbon, alumina, zirconia, silica, titania, zeolite, silica alumina, and chromium oxide. Examples of carbon include activated carbon, amorphous carbon, graphite, and diamond. These supports may be used alone or in combination of two or more types. Among them, carbon is preferred from the viewpoint of a large specific surface area and easy support of the alkali metal fluoride, and activated carbon is more preferred.

When the alkali metal fluoride is supported on a carrier, there is no particular restriction on the amount of the supported alkali metal fluoride, but from the viewpoint of being able to produce vinyl fluoride compounds with particularly high conversion rates, yields, and selectivities, it is preferable that the alkali metal fluoride content is 0.1 to 75 mass%, and more preferably 1 to 60 mass%, of 100 mass% of the total amount of alkali metal fluoride supported on a carrier.

The bulk density of the alkali metal fluoride supported on a carrier is preferably 0.01 to 10 g/mL, more preferably 0.1 to 5 g/mL, from the viewpoint of being able to produce vinyl fluoride compounds with particularly high conversion rates, yields, and selectivities. In the present disclosure, the bulk density of the alkali metal fluoride supported on a carrier is measured using a bulk density measuring device. When the bulk density of the alkali metal fluoride supported on a carrier is within this range, the density of the particles of the alkali metal fluoride supported on a carrier is not too small, and the target compound can be obtained with a higher selectivity. It is also possible to further improve the conversion rate of the substrate.

The pore volume of the alkali metal fluoride supported on a carrier is preferably 0.1 to 1.5 mL/g, and more preferably 0.25 to 1.0 mL/g, from the viewpoint of being able to produce vinyl fluoride compounds with particularly high conversion rates, yields, and selectivities. In the present disclosure, the pore volume of the alkali metal fluoride supported on a carrier is measured by the BET method. When the pore volume of the alkali metal fluoride supported on a carrier is within this range, the density of the particles of the alkali metal fluoride supported on a carrier is not too small, and the target compound can be obtained with a higher selectivity. It is also possible to further improve the conversion rate of the substrate.

The average pore diameter of the alkali metal fluoride supported on a carrier is preferably 5 to 20 μm, and more preferably 8 to 15 μm, from the viewpoint of being able to produce vinyl fluoride compounds with particularly high conversion rates, yields, and selectivities. In this disclosure, the average pore diameter of the alkali metal fluoride supported on a carrier is measured by the BET method.

(1-4) Fluorine-containing gas The above-mentioned alkali metal fluorides also function as catalysts, and can produce vinyl fluoride compounds with particularly high conversion, yield and selectivity. However, the alkali metal fluorides contain fluorine atoms, and the fluorine atoms may be extracted during the reaction to obtain the vinyl fluoride compound represented by the general formula (1). Therefore, the amount of alkali metal fluoride that effectively functions as a catalyst may decrease as the reaction proceeds for a long time. For this reason, it is preferable to carry out the above reaction in the presence of a fluorine-containing gas in order to replenish fluorine atoms.

Such fluorine-containing gases are not particularly limited, and examples thereof include F2, _HF , _CFCl3 , _CF2Cl2 , _CFHCl2 , _CF2HCl , _CF3H , _NF3 , _IF5 , _IF7 , FCl, _ClF3 , and _the like.

In this disclosure, when the reaction is carried out in the gas phase, it is preferable to blow in the fluorine-containing gas in a gaseous state (gas phase).

(1-5) Reaction Temperature In the step of obtaining a vinyl fluoride compound by reacting a vinyl halide compound in the present disclosure, the reaction temperature is usually preferably 200 to 500° C., more preferably 250 to 450° C., and even more preferably 300 to 400° C., from the viewpoint of producing a vinyl fluoride compound with particularly high conversion rate, yield, and selectivity.

(1-6) Reaction Time In the present disclosure, when the reaction is carried out in the gas phase, for example, when a gas-phase flow system is adopted, the reaction time is the contact time (W/F) of the raw material compound (vinyl halide compound) to the catalyst (alkali metal fluoride) [W: weight of the catalyst including alkali metal fluoride (total weight including the carrier in the case of an alkali metal fluoride supported on a carrier) (g), F: flow rate (cc/sec) of the raw material compound (vinyl halide compound)], from the viewpoint of a particularly high conversion rate of the reaction and a higher yield and higher selectivity of the vinyl fluoride compound, preferably 5 to 200 g·sec./cc, more preferably 10 to 150 g·sec./cc, and even more preferably 15 to 100 g·sec./cc. Note that the above contact time means the time during which the raw material compound and the catalyst are in contact with each other.

The above contact times indicate the conditions when the reaction is carried out in the gas phase, particularly in a gas phase continuous flow system, but they can also be adjusted appropriately when the reaction is carried out in a batch system.

In the present disclosure, when the reaction step is carried out in the presence of a fluorine-containing gas, the content of the fluorine-containing gas is preferably 0.1 to 10 moles, more preferably 0.5 to 5 moles, and even more preferably 1 to 2.5 moles per mole of the raw material compound (vinyl halide compound), from the viewpoint of particularly high conversion rate of the reaction and obtaining a vinyl fluoride compound with a higher yield and higher selectivity.

(1-7) Reaction Pressure The reaction pressure when a vinyl fluoride compound is obtained by reacting a vinyl halide compound in the present disclosure is preferably -0.05 to 2 MPa, more preferably -0.01 to 1 MPa, and even more preferably normal pressure to 0.5 MPa, from the viewpoint of producing a vinyl fluoride compound with a particularly high conversion rate, yield, and selectivity. In the present disclosure, the pressure is a gauge pressure unless otherwise specified.

In the reaction of the present disclosure, the reactor in which the raw material compound (vinyl halide compound) is reacted in the presence of an alkali metal fluoride and, if necessary, a gas containing fluorine is used, is not particularly limited in shape and structure as long as it can withstand the above-mentioned temperature and pressure. Examples of the reactor include a vertical reactor, a horizontal reactor, and a multi-tube reactor. Examples of the material of the reactor include glass, stainless steel, iron, nickel, and iron-nickel alloys.

(1-8) Examples of reactions The reaction step in the present disclosure for obtaining a vinyl fluoride compound by reacting a vinyl halide compound can be carried out by either a continuous gas phase flow system or a batch system in which a raw material compound (vinyl halide compound) is continuously charged into a reactor and a target compound (vinyl fluoride compound) is continuously withdrawn from the reactor. If the target compound remains in the reactor, the elimination reaction may proceed further, so it is preferable to carry out the reaction in a continuous gas phase flow system. In the present disclosure, the reaction step for obtaining a vinyl fluoride compound by reacting a vinyl halide compound is carried out in the gas phase, and in particular, it is preferable to carry out the reaction in a continuous gas phase flow system using a fixed bed reactor. When the reaction is carried out in a continuous gas phase flow system, the apparatus, operation, etc. can be simplified and it is economically advantageous.

In the present disclosure, the reaction step of reacting a vinyl halide compound to obtain a vinyl fluoride compound is preferably carried out under an inert gas atmosphere in order to suppress deterioration of the alkali metal fluoride. Examples of the inert gas include nitrogen, helium, and argon. Among these inert gases, nitrogen is preferred in terms of reducing costs. The concentration of the inert gas is preferably 0 to 50 mol% of the gas components introduced into the reactor. When the reaction is carried out in the presence of a fluorine-containing gas, the reaction can be carried out under an atmosphere of the fluorine-containing gas or a mixed atmosphere of the inert gas and the fluorine-containing gas. The concentration of the fluorine-containing gas is preferably 0.1 to 90 mol% of the gas components introduced into the reactor.

After the reaction is complete, purification can be performed according to standard methods as necessary to obtain the vinyl fluoride compound represented by general formula (1).

(1-9) Target Compound The target compound of the present disclosure thus obtained is represented by the general formula (1):
CHR ¹ = CFR ² (1)
[In the formula, ^R1 represents a hydrogen atom, a halogen atom, an alkyl group, or a fluoroalkyl group. ^R2 represents a halogen atom, an alkyl group, or a fluoroalkyl group. However, when ^R2 is a fluoroalkyl group, ^R1 is a halogen atom, an alkyl group, or a fluoroalkyl group.]
It is a vinyl fluoride compound represented by the formula:

This vinyl fluoride compound may contain both cis and trans isomers, but the trans isomer is preferred from the viewpoint of being able to produce it with a high conversion rate, yield and selectivity, and is represented by the general formula (1A):

[In the formula, ^R1 and ^R2 are the same as above.]
Preferred are vinyl fluoride compounds represented by the following formula:

^R1 and ^R2 in the general formulae (1) and (1A) correspond to ^R1 and ^R3 in the general formulae (2) and (2A) described above. When ^R3 in the general formulae (2) and (2A) is a halogen atom other than a fluorine atom, the target compound, the fluorinated vinyl compound, may include a compound in which the halogen atom is replaced by a fluorine atom and a compound in which the halogen atom remains as it is. Therefore, the vinyl fluorinated compound represented by the general formulae (1) and (1A) to be produced may be, for example, specifically:

These include:

The vinyl fluoride compounds obtained in this way can be effectively used for a variety of purposes, such as etching gases for forming cutting-edge microstructures in semiconductors, liquid crystals, etc., cleaning gases, and building blocks for organic synthesis. Building blocks for organic synthesis will be described later.

2. Composition A vinyl fluoride compound can be obtained as described above. The vinyl fluoride compound represented by the general formula (1) or (1A) and the vinyl fluoride compound represented by the general formula (3):
^R1- C≡C- ^R2 (3)
[In the formula, ^R1 and ^R2 are the same as above.]
The compound may be obtained in the form of a composition containing an alkyne compound represented by the formula:

In this case, the content of the vinyl fluoride compound represented by general formula (1) is preferably 60 to 99.9 mol%, more preferably 80 to 99 mol%, based on the total amount of the composition of the present disclosure being 100 mol%. The content of the alkyne compound represented by general formula (3) is preferably 0.1 to 20 mol%, more preferably 0.2 to 10 mol%, based on the total amount of the composition of the present disclosure being 100 mol%. Note that when the vinyl fluoride compound represented by general formula (1) contains both general formulas (1A1) and (1A2) as described below, the above content is the total amount.

As described above, when ^R3 in the general formulae (2) and (2A) is a halogen atom other than a fluorine atom, the target vinyl fluoride compound may include a compound in which the halogen atom is replaced with a fluorine atom and a compound in which the halogen atom remains as it is.

For this reason, the vinyl fluoride compounds represented by the general formulas (1) and (1A) include the general formula (1A1):

[In the formula, R ¹ represents a hydrogen atom, a halogen atom, an alkyl group, or a fluoroalkyl group.]
and a difluorovinyl compound represented by the formula:
General formula (1A2):

[In the formula, R ¹ represents a hydrogen atom, a halogen atom, an alkyl group or a fluoroalkyl group. X ¹ represents a halogen atom other than a fluorine atom.]
and a vinyl fluoride compound represented by the formula:

In the general formulae (1A) and (1B), R ¹ can be as defined above, and examples of the halogen atom other than a fluorine atom represented by X ¹ include a chlorine atom, a bromine atom and an iodine atom.

In this case, the content of the difluorovinyl compound represented by general formula (1A1) is preferably 40 to 98 mol%, more preferably 50 to 90 mol%, based on the total amount of the composition of the present disclosure being 100 mol%. Also, the content of the difluorovinyl compound represented by general formula (1A2) is preferably 2 to 30 mol%, more preferably 3 to 20 mol%, based on the total amount of the composition of the present disclosure being 100 mol%.

In addition, according to the manufacturing method of the present disclosure, even when the above-mentioned composition is obtained, the vinyl fluoride compound represented by general formula (1) can be obtained in one step with a high reaction conversion rate, high yield, and high selectivity, and therefore it is possible to reduce components other than the vinyl fluoride compound represented by general formula (1) in the composition, thereby reducing the purification effort required to obtain the vinyl fluoride compound represented by general formula (1).

The composition of the present disclosure can be effectively used for a variety of applications, including as an etching gas for forming cutting-edge fine structures in semiconductors, liquid crystals, etc., as a building block for organic synthesis, a cleaning gas, etc. The building block for organic synthesis means a substance that can be a precursor of a compound having a highly reactive skeleton. For example, when the composition of the present disclosure is reacted with a fluorine-containing organosilicon compound such as CF ₃ Si(CH ₃ ) ₃ , a fluoroalkyl group such as a CF ₃ group can be introduced to convert the composition into a substance that can be a cleaning agent or a fluorine-containing pharmaceutical intermediate.

Although the embodiments of the present disclosure have been described above, various modifications of form and details are possible without departing from the spirit and scope of the claims.

The following examples are presented to clarify the features of the present disclosure. The present disclosure is not limited to these examples.

Synthesis example 1: 50%CsF/AC
Activated carbon (specific surface area ^1200m2 /g) and cesium fluoride were mixed so that the amount of cesium fluoride used was 50% by mass, with the total amount of activated carbon and cesium fluoride being 100% by mass, to obtain a 50% CsF/AC catalyst in which cesium fluoride is supported on activated carbon. The specific surface area of the obtained catalyst was ^600cm2 /g, the pore volume was 0.7mL/g, and the pore diameter was 10μm.

Synthesis example 2: 5%CsF/AC
Activated carbon (specific surface area ^1200m2 /g) and cesium fluoride were mixed so that the amount of cesium fluoride used was 5% by mass, with the total amount of activated carbon and cesium fluoride being 100% by mass, to obtain a 5%CsF/AC catalyst in which cesium fluoride is supported on activated carbon. The specific surface area of the obtained catalyst was ^900cm2 /g, the pore volume was 0.8mL/g, and the pore diameter was 10μm.

Synthesis Example 3: 5%KF/AC
Activated carbon (specific surface area ^1200m2 /g) and potassium fluoride were mixed so that the amount of potassium fluoride used was 5% by mass, with the total amount of activated carbon and potassium fluoride being 100% by mass, to obtain a 5% KF/AC catalyst in which cesium fluoride is supported on activated carbon. The specific surface area of the obtained catalyst was ^900cm2 /g, the pore volume was 0.8mL/g, and the pore diameter was 10μm.

Examples 1 to 5
In the methods for producing vinyl fluoride compounds in Examples 1 to 5, the raw material compound is a vinyl halide compound represented by the general formula (2), in which R ¹ and R ³ are trifluoromethyl groups and X is a chlorine atom, and the compound is represented by the following reaction formula:

The vinyl fluoride compound was obtained according to the following procedure.

10 g of the catalyst obtained in Synthesis Example 1, 2 or 3 was placed in a stainless steel pipe (outer diameter: 1/2 inch) serving as a reaction tube. After drying at 200°C for 2 hours under a nitrogen atmosphere, _CF3CH = _CClCF3 (raw material compound) was passed through the reaction tube at normal pressure so that the contact time (W/F) between _CF3CH = _CClCF3 (raw material compound) and the catalyst was 16.0 g·sec/cc or 42.0 g·sec/cc.

The reaction was carried out in a continuous gas phase flow system.

The reaction was started by heating the reaction tube to 300°C or 400°C.

One hour after the reaction started, the distillate that passed through the detoxification tower was collected.

Mass analysis was then performed by gas chromatography/mass spectrometry (GC/MS) using a gas chromatograph (Shimadzu Corporation, product name "GC-2014"), and structural analysis was performed by NMR spectroscopy using an NMR (JEOL, product name "400YH").

Mass spectrometry and structural analysis confirmed that the target compound was CF ₃ CH═CFCF _3. The results are shown in Table 1.

Examples 6 to 8
In the methods for producing vinyl fluoride compounds in Examples 6 to 8, the raw material compound is a vinyl halide compound represented by the general formula (2), in which R ¹ is a hydrogen atom, R ³ and X are chlorine atoms, and the compound is represented by the following reaction formula:

The vinyl fluoride compound was obtained according to the following procedure.

10 g of the catalyst obtained in Synthesis Example 1 or 3 was placed in a stainless steel pipe (outer diameter: 1/2 inch) serving as a reaction tube. After drying at 200°C for 2 hours under a nitrogen atmosphere, _CH2 = _CCl2 (raw material compound) was passed through the reaction tube at normal pressure so that the contact time (W/F) between _CH2 = _CCl2 (raw material compound) and the catalyst was 10.0 g·sec/cc or 20.0 g·sec/cc.

The reaction was carried out in a continuous gas phase flow system.

The reaction was started by heating the reaction tube to 400°C.

One hour after the reaction started, the distillate that passed through the detoxification tower was collected.

Mass analysis was then performed by gas chromatography/mass spectrometry (GC/MS) using a gas chromatograph (Shimadzu Corporation, product name "GC-2014"), and structural analysis was performed by NMR spectroscopy using an NMR (JEOL, product name "400YH").

Mass spectrometry and structural analysis confirmed that the target compounds were CH ₂ ═CClF and CH ₂ ═CF _2. The results are shown in Table 2.

Claims (7)

General formula (1):
CHR ¹ = CFR ² (1)
[wherein ^R1 represents a hydrogen atom, a halogen atom, an alkyl group or a fluoroalkyl group; ^{and R2} represents a halogen atom, an alkyl group or a fluoroalkyl group; provided that when ^R2 is a fluoroalkyl group, ^R1 is a halogen atom, an alkyl group or a fluoroalkyl group], the method for producing a vinyl fluoride compound represented by the following formula is provided:
In the presence of an alkali metal fluoride,
General formula (2):
CHR ¹ = CXR ³ (2)
[In the formula, ^R1 represents a hydrogen atom, a halogen atom, an alkyl group or a fluoroalkyl group. ^R3 represents a halogen atom, an alkyl group or a fluoroalkyl group. However, when ^R3 is a fluoroalkyl group, ^R1 is a halogen atom, an alkyl group or a fluoroalkyl group. X represents a halogen atom other than a fluorine atom.]
a reaction step of reacting a vinyl halide compound represented by the general formula (1) to obtain a vinyl fluoride compound represented by the general formula (1),
the alkali metal fluoride is potassium fluoride and/or cesium fluoride;
the reaction step is carried out in a gas-phase continuous flow system , the contact time (W/F) of the vinyl halide compound with the catalyst containing the alkali metal fluoride is 5 to 200 g·sec/cc, and the reaction temperature in the reaction step is 200 to 450° C. The vinyl fluoride compound represented by the general formula (1) is represented by the general formula (1A):

[In the formula, ^R1 and ^R2 are the same as above.]
The method according to claim 1, wherein the vinyl fluoride compound is represented by the formula: The vinyl halide compound represented by the general formula (2) is represented by the general formula (2A):

[In the formula, R ¹ , R ³ and X are the same as above.]
The method according to claim 1 or 2, wherein the vinyl halide compound is represented by the formula: The method according to any one of claims 1 to 3, wherein the alkali metal fluoride is supported on a carrier. 5. The method according to claim 4, wherein the alkali metal fluoride supported on the carrier has a specific surface area of 500 to 2000 ^{m 2} /g. The manufacturing method according to claim 4 or 5, wherein the content of the alkali metal fluoride is 0.1 to 75 mass%, with the total amount of the carrier and the alkali metal fluoride being 100 mass%. The method according to any one of claims 1 to 6, wherein the reaction step is carried out in the presence of a gas containing fluorine.