TWI777113B - The production method of cyclobutene - Google Patents

Abstract

(式中，X¹ 、X² 、X³ 及X⁴ 係相同或相異地表示氫原子、鹵素原子或全氟烷基。Y表示鹵素原子。)

(式中，X¹ 、X² 、X³ 、X⁴ 及Y係與前述相同。X⁵ 及X⁶ 係相同或相異地表示氫原子、鹵素原子、或全氟烷基。)An object of the present disclosure is to produce a halogen atom-containing cyclobutene with high selectivity. A method for producing cyclobutene represented by the general formula (1), comprising the step of making the cyclobutane represented by the general formula (2) carry out a desorption reaction, and the step of carrying out the aforementioned desorption reaction in a gas phase;

(In the formula, X ¹ , X ² , X ³ and X ⁴ represent a hydrogen atom, a halogen atom or a perfluoroalkyl group identically or differently. Y represents a halogen atom.)

(In the formula, X ¹ , X ² , X ³ , X ⁴ , and Y are the same as described above. X ⁵ and X ⁶ represent the same or different hydrogen atoms, halogen atoms, or perfluoroalkyl groups.)

Description

Manufacturing method of cyclobutene

The present disclosure relates to a method for producing cyclobutene.

Cyclobutene containing a halogen atom is a compound useful as a dry etching gas for semiconductors, various refrigerants, foaming agents, heat transfer media, and the like.

Among cyclobutenes containing halogen atoms, as for 1H-pentafluorocyclobutene, a method for producing 1H-pentafluorocyclobutene from 1H,2H-hexafluorocyclobutane by dehydrofluorination is known (for example, , Non-Patent Documents 1 and 2). This technique is for the synthesis of 1H-pentafluorocyclobutene in an open reaction system using glassware. [Prior Art Literature] [Non-patent literature]

[Non-Patent Document 1] Buxton; Tatlow; Journal of the Chemical Society; (1954); p. 1177 - 1179 [Non-Patent Document 2] Fuller, G.; Tatlow, J.C.; Journal of the Chemical Society; (1961); p. 3198 - 3203

[The problem to be solved by the invention]

An object of the present disclosure is to produce a halogen atom-containing cyclobutene with high selectivity. [means to solve the problem]

The present disclosure includes the following constitutions.

Item 1. A method for producing cyclobutene represented by the general formula (1), comprising the step of making the cyclobutane represented by the general formula (2) carry out a desorption reaction, and the step of carrying out the aforementioned desorption reaction in a gas phase;

(In the formula, X ¹ , X ² , X ³ and X ⁴ are the same or different, and represent a hydrogen atom, a halogen atom, or a perfluoroalkyl group. Y represents a halogen atom.)

(In the formula, X ¹ , X ² , X ³ , X ⁴ , and Y are the same as described above. X ⁵ and X ⁶ represent the same or different hydrogen atoms, halogen atoms, or perfluoroalkyl groups.)

Item 2. The production method according to the aforementioned Item 1, wherein the X ⁵ is a hydrogen atom, the X ⁶ is a halogen atom, and the desorption reaction is a dehydrohalogenation reaction.

Item 3. A composition containing the cyclobutene represented by the general formula (1), the total amount of the composition is set as 100 mol%, and the content of the cyclobutene represented by the aforementioned general formula (1) is 95 mol% or more;

(In the formula, X ¹ , X ² , X ³ and X ⁴ represent a hydrogen atom, a halogen atom or a perfluoroalkyl group identically or differently. Y represents a halogen atom.)

Item 4. The composition of item 3 above, wherein the content of 1H-perfluorocyclobutene (1H-cC ₄ F ₅ H) is 99 mol% or more, 3H-perfluorocyclobutene (3H-cC ₄ F ₅ H) ) is less than 1 mol%.

Item 5. The composition according to the aforementioned item 3 or 4, which is used as a cleaning gas, an etching gas, a deposition gas, or a building element for organic synthesis. [Effect of invention]

According to the present disclosure, cyclobutene containing halogen atoms can be produced with high selectivity.

As a result of careful research by the present inventors, it was found that cyclobutane containing a halogen atom represented by the general formula (1) can be produced with high selectivity by carrying out the step of desorbing the raw material compound in the gas phase. ene.

The present disclosure is based on the knowledge and insights, and has been completed as a result of repeated research.

The present disclosure includes the following embodiments.

The method for producing the cyclobutene represented by the general formula (1) of the present disclosure includes the step of subjecting the cyclobutane represented by the general formula (2) to a desorption reaction.

(In the formula, X ¹ , X ² , X ³ and X ⁴ represent a hydrogen atom, a halogen atom or a perfluoroalkyl group identically or differently. Y represents a halogen atom.)

(In the formula, X ¹ , X ² , X ³ , X ⁴ , and Y are the same as described above. X ⁵ and X ⁶ represent the same or different hydrogen atoms, halogen atoms, or perfluoroalkyl groups.)

The present disclosure is to carry out the step of the aforementioned desorption reaction in the gas phase.

In the present disclosure, by satisfying the above requirements, cyclobutene containing a halogen atom can be produced with high selectivity.

In the present disclosure, "selectivity" means the total molar amount of compounds other than the raw material compounds (cyclobutene including halogen atoms, etc.) in the effluent gas from the reactor outlet, the effluent gas contained in the effluent gas. The ratio (mol%) of the total molar amount of the target compound (cyclobutene containing a halogen atom).

In the present disclosure, "conversion rate" means compounds other than the raw material compound contained in the effluent gas from the reactor outlet relative to the molar amount of the raw material compound (cyclobutane containing halogen atoms) supplied to the reactor The ratio (mol %) of the total molar amount (such as cyclobutene including a halogen atom).

In addition, since the method for producing cyclobutene of the present disclosure is not a batch reaction but a gas-phase reaction in a circulation system, it has the advantages that no solvent is required and no industrial waste is generated.

(1) Raw material compounds In the present disclosure, the starting compound is cyclobutane represented by the general formula (2).

(In the formula, X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ represent a hydrogen atom, a halogen atom or a perfluoroalkyl group identically or differently. Y represents a halogen atom.)

X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ represent a hydrogen atom, a halogen atom, or a perfluoroalkyl group identically or differently.

Y represents a halogen atom.

The halogen atoms of X ¹ , X ² , X ³ , X ⁴ , X ⁵ , X ⁶ and Y include, for example, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

The perfluoroalkyl groups of X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ are alkyl groups in which all hydrogen atoms are substituted with fluorine atoms. For example, the perfluoroalkyl group has 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms, and particularly preferably 1 to 3 carbon atoms. The perfluoroalkyl group is preferred. The perfluoroalkyl group is preferably a straight-chain or branched-chain perfluoroalkyl group. As the aforementioned perfluoroalkyl group, trifluoromethyl (CF ₃ -) and pentafluoroethyl (C ₂ F ₅ -) are preferable.

The halogen atom-containing cyclobutane represented by the general formula (2) as the raw material compound is represented by X ¹ , X ² , X ³ and X ⁴ from the viewpoint that the halogen atom-containing cyclobutene can be produced with high selectivity. The same or different represents a hydrogen atom, a halogen atom or a perfluoroalkyl group, and X ⁵ is a hydrogen atom, X ⁶ is a fluorine atom, and Y is preferably a fluorine atom.

The cyclobutane represented by the general formula (2) as the starting compound includes, for example,

and other compounds.

The cyclobutanes represented by the general formula (2) can be used alone or in combination of two or more. As such a cyclobutane system, a commercial item can be used.

The halogen atom-containing cyclobutane represented by the general formula (2) is represented by X ¹ , X ² , X ³ , X ⁴ and X ⁶ from the viewpoint of producing a halogen atom-containing cyclobutene with high selectivity. A fluorine atom, X ⁵ is preferably a hydrogen atom, and Y is a fluorine atom.

(2) Detachment reaction The step of carrying out the dissociation reaction in the present disclosure is to carry out the dissociation reaction in the gas phase. The step of carrying out the desorption reaction of the present disclosure is carried out in the gas phase, especially preferably in a gas-phase continuous flow mode using a fixed bed reactor. When the gas-phase continuous flow type is used, not only the equipment, operation, etc. can be simplified, but also economical efficiency can be achieved.

In the present disclosure, in the step of performing the desorption reaction, the aforementioned X ⁵ is a hydrogen atom, the aforementioned X ⁶ is a halogen atom, and the aforementioned desorption reaction is preferably a dehydrohalogenation reaction. In the present disclosure, in the step of performing the desorption reaction, the aforementioned X ⁵ is a hydrogen atom, the aforementioned X ⁶ is a fluorine atom, and the aforementioned desorption reaction is preferably a dehydrofluorination reaction.

For example, as a starting compound, in the halogen atom-containing cyclobutane represented by the general formula (2), X ¹ , X ² , X ³ , X ⁴ and X ⁶ are fluorine atoms, X ⁵ is a hydrogen atom, and Y is a A fluorine atom is preferred.

Preferably, the desorption reaction is a dehydrofluorination reaction according to the following reaction formula.

catalyst In the present disclosure, the step of carrying out the desorption reaction is preferably carried out in the gas phase in the presence of a catalyst.

The catalyst used in this step is preferably activated carbon. The catalyst used in this step is preferably a metal catalyst. As a metal catalyst, selected from the group consisting of chromium oxide, chromium oxide fluoride, chromium fluoride, aluminum oxide, aluminum oxide fluoride, aluminum fluoride, iron oxide, iron oxide fluoride, iron fluoride, nickel oxide, oxide fluoride At least one of the group consisting of nickel, nickel fluoride, magnesium oxide, magnesium oxide fluoride and magnesium fluoride is preferred.

Among these catalysts, activated carbon, chromium oxide, fluorided chromium oxide, alumina, and fluorided alumina are preferred from the viewpoint of obtaining the target compound with a higher selectivity. In addition, the conversion rate of the raw material compound can be further improved.

In this step, when the raw material compound is brought into contact with the catalyst in the gas phase, the catalyst is preferably brought into contact with the raw material compound in a solid state (solid phase).

In this step, the catalyst can also be in powder form, but in the gas-phase continuous flow reaction, it is preferably in the form of pellets.

The specific surface area of the catalyst (hereinafter, also referred to as BET specific surface area) measured by the BET method is usually 10 to 3,000 m ² /g, preferably 10 to 400 m ² /g, more preferably 20 to 375 m ² /g, more preferably 30 to 350 m ² /g. When the BET specific surface area of the catalyst is in this range, the target compound can be obtained with high selectivity because the particle density of the catalyst will not be too small. In addition, the conversion rate of the raw material compound can also be improved.

When using activated carbon as a catalyst, it is preferable to use powdered activated carbon such as crushed carbon, shaped carbon, granular carbon, spherical carbon, etc. The powdered activated carbon is preferably powdered activated carbon with a particle size of 4 meshes (4.76mm) to 100 meshes (0.149mm) under the JIS test.

When a metal catalyst is used as a catalyst, it is preferable to carry it on a carrier. Examples of the carrier include carbon, aluminum oxide (Al ₂ O ₃ ), zirconium oxide (ZrO ₂ ), silicon dioxide (SiO ₂ ), titanium oxide (TiO ₂ ), and the like. As carbon, activated carbon, amorphous carbon, graphite, diamond, etc. are mentioned, for example.

As an example of the catalyst in the present disclosure, a description will be given of chromium oxide and fluorinated chromium oxide. When the chromium oxide is represented by Cr ₂ O ₃ ･nH ₂ O as chromium oxide, for example, the value of n is preferably 3 or less, more preferably 1 to 1.5. In addition, in the composition formula of the chromium oxide: CrO _m , it is preferable that m is usually in the range of 1.5<m<3. As a catalyst, fluorinated chromium oxide can be prepared by fluorinating chromium oxide. Examples of fluorination include fluorination with hydrogen fluoride (HF), fluorination with fluorocarbon, and the like.

The fluorinated chromium oxide system as a catalyst can be obtained by, for example, the method described in Japanese Patent No. 3412165 . Fluorinated chromium oxide can be obtained by fluorinating chromium oxide with hydrogen fluoride (HF treatment). The temperature of the fluorination is preferably 100 to 460°C, for example. The pressure of the fluorination is preferably the pressure supplied to the catalyst reaction. In the present disclosure, it is preferable to use a highly fluorinated-chromia catalyst with a large fluorine content. Highly fluorinated-chromia catalysts can be obtained by fluorination of chromium oxide at higher temperatures than usual for extended periods of time.

The fluorine content of the highly fluorinated-chromium oxide catalyst is preferably 30% by mass or more, more preferably 30 to 45% by mass. The fluorine content can be measured by the mass change of the catalyst, or the quantitative analysis method of general chromium oxide.

release reaction temperature In the step of carrying out the dissociation reaction of the present disclosure, the lower limit of the reaction temperature is from the viewpoint of enabling the dissociation reaction to proceed more efficiently and obtaining the target compound with a higher selectivity, and from the viewpoint of suppressing the reduction of the conversion rate, usually It is 50°C, preferably 200°C, preferably 250°C, more preferably 300°C, and particularly preferably 350°C.

The upper limit of the reaction temperature of the dehydrofluorination reaction is from the viewpoint that the dehydrofluorination reaction can be carried out more efficiently and the target compound can be obtained with a higher selectivity, and the selectivity caused by the inhibition of decomposition or polymerization of the reaction product From the viewpoint of lowering, it is usually 500°C, preferably 450°C, more preferably 400°C.

Detachment reaction time The reaction time of detachment reaction is as long as the contact time of the raw material compound to the catalyst (W/F ₀ ) [W: the weight of the metal catalyst (g), F ₀ : the flow rate of the raw material compound (cc/sec) ] can improve the conversion rate of raw material compounds, but the amount of catalyst will increase and the equipment will become larger, so it is not efficient.

Therefore, the reaction time of the dehydrofluorination reaction is from the viewpoint of improving the conversion rate of the raw material compound and reducing the equipment cost, and the contact time (W/F ₀ ) of the raw material compound to the catalyst is 5g･sec/cc~300g･ sec/cc is better, 10g･sec/cc~200g･sec/cc is better, 15g･sec/cc~ 150g･sec/cc is better, 20g･sec/cc~100g･sec/cc Excellent.

The above-mentioned contact time between the raw material compound and the catalyst means the time during which the raw material compound and the catalyst are in contact.

When the dissociation reaction of the present disclosure is carried out in the gas phase in the presence of a catalyst, the reaction temperature and reaction time (contact time) can be appropriately adjusted with a catalyst, that is, the target compound can be obtained with a higher selectivity.

When chromium oxide is used as a catalyst, the reaction temperature is preferably 300°C or higher, more preferably 350°C or higher. In addition, the contact time is preferably 10 g･sec/cc or more, more preferably 20 g･sec/cc or more, and more preferably 40 g･sec/cc or more.

When alumina is used as a catalyst, the reaction temperature is preferably 300°C or more, and the contact time is preferably 5g･sec/cc or more.

When activated carbon is used as a catalyst, the reaction temperature is preferably 300°C or higher, more preferably 350°C or higher, and more preferably 400°C or higher. Also, the contact time is preferably 5g･sec/cc~55g･sec/cc, preferably 5g･sec/cc~50g･sec/cc, more preferably 5g･sec/cc~40g･sec/cc good.

out of reaction pressure The reaction pressure of the desorption reaction is preferably -0.05MPa~2MPa, preferably -0.01MPa~1MPa, and more preferably normal pressure~0.5MPa, from the viewpoint of more efficient desorption reaction. Moreover, in the present disclosure, when the pressure is not indicated, it is the gauge pressure.

In the desorption reaction, the shape and structure are not particularly limited as long as the reactor for reacting the raw material compound and the catalyst (metal catalyst, etc.) can withstand the above-mentioned temperature and pressure. As a reactor, for example, a vertical reactor, a horizontal reactor, a multi-tubular reactor, etc. are mentioned. As a material of a reactor, glass, stainless steel, iron, nickel, iron-nickel alloy, etc. are mentioned, for example.

Example of a disengagement reaction The stripping reaction can be carried out by either a flow-through method or a batch method in which the raw material compound is continuously fed into the reactor and the target compound is continuously extracted from the reactor. When the target compound is retained in the reactor, since the desorption reaction may proceed further, it is preferable to carry out the flow-through method. The step of carrying out the desorption reaction of the present disclosure is carried out in the gas phase, especially in a gas-phase continuous flow type using a fixed-bed reactor. When it is carried out by the gas-phase continuous flow type, not only the equipment, operation, etc. can be simplified, but also economical efficiency is advantageous.

The environment in which the desorption reaction is carried out is preferably in the presence of an inert gas and/or in the presence of hydrogen fluoride from the viewpoint of suppressing the deterioration of the catalyst (metal catalyst, etc.). The inert gas system is preferably at least one selected from the group consisting of nitrogen, helium, argon and carbon dioxide. Among these inert gases, nitrogen is preferable from the viewpoint of cost reduction. The concentration of the inert gas is preferably 0 to 50 mol% of the gas components introduced into the reactor.

After completion of the desorption reaction, if necessary, purification treatment is carried out according to an ordinary method, and the halogen atom-containing cyclobutene represented by the general formula (1) can be obtained.

(3) target compound The objective compound of the present disclosure is a halogen atom-containing cyclobutene represented by the general formula (1).

(In the formula, X ¹ , X ² , X ³ and X ⁴ represent a hydrogen atom, a halogen atom or a perfluoroalkyl group identically or differently. Y represents a halogen atom.)

X ¹ , X ² , X ³ and X ⁴ , and Y are the same as described above.

The cyclobutenes represented by the general formula (1) to be produced include, for example, the following

and other compounds.

In the halogen atom-containing cyclobutene represented by the general formula (1), X ¹ , X ² , X ³ and X ⁴ represent a hydrogen atom, a halogen atom or a perfluoroalkyl group identically or differently, and Y represents a fluorine atom better. In the halogen atom-containing cyclobutene represented by the general formula (1), X ¹ , X ² , X ³ and X ⁴ are preferably fluorine atoms, and Y is preferably a fluorine atom.

In the method for producing a halogen atom-containing cyclobutene of the present disclosure, the halogen atom-containing cyclobutane represented by the general formula (2) is used as a raw material compound, and X ¹ , X ² , X ³ , X ⁴ and X ^{6 The} desorption reaction is preferable when X is a fluorine atom, X5 is a hydrogen atom, and Y is a fluorine atom.

It is preferable that the desorption reaction is a dehydrofluorination reaction according to the following reaction formula.

The target compound is a halogen atom-containing cyclobutene represented by the general formula (1), wherein X ¹ , X ² , X ³ and X ⁴ are fluorine atoms, and Y is preferably a fluorine atom.

(4) Composition containing cyclobutene containing halogen atom Through the above operation, the cyclobutene containing halogen atoms represented by the general formula (1) can be obtained, and as above, there are also cyclobutene containing halogen atoms represented by the general formula (1), which is different from the general formula (1). The case where it is obtained in the form of the composition of cyclobutane containing a halogen atom represented by the formula (2).

The halogen atom-containing cyclobutene represented by the general formula (1) contained in the composition is preferably such that X ¹ , X ² , X ³ and X ⁴ are fluorine atoms, and Y is a fluorine atom.

In the composition comprising the halogen atom-containing cyclobutene represented by the general formula (1) of the present disclosure, the total amount of the aforementioned composition is set to 100 mol %, and the halogen atom-containing cyclobutene represented by the general formula (1) The content of alkene is preferably 95 mol% or more, preferably 99 mol% or more.

In the composition comprising the halogen atom-containing cyclobutene represented by the general formula (1) of the present disclosure, the total amount of the aforementioned composition is set to 100 mol %, and the halogen atom-containing cyclobutene represented by the general formula (1) The content of alkene is preferably 1 mol % to 99.9 mol %, preferably 5 mol % to 99.9 mol %, and more preferably 10 mol % to 99.9 mol %.

In the method for producing a halogen atom-containing cyclobutene of the present disclosure, the above-mentioned desorption reaction system may generate the following compounds as impurities.

In the composition comprising the halogen atom-containing cyclobutene represented by the general formula (1) of the present disclosure, the total amount of the aforementioned composition is set as 100 mol %, and 1H-perfluorocyclobutene (1H-cC ₄ F The content of ₅ H) is 99 mol% or more, and the content of 3H-perfluorocyclobutene (3H-cC ₄ F ₅ H) is preferably 1 mol % or less.

According to the production method of the present disclosure, even if it is obtained as a composition containing the halogen atom-containing cyclobutene represented by the general formula (1), the compound represented by the general formula (1) can be obtained with an extremely high selectivity. As a result of the halogen atom-containing cyclobutene, components other than the halogen atom-containing cyclobutene represented by the general formula (1) in the aforementioned composition can be reduced. According to the production method of the present disclosure, the labor for purification to obtain the halogen atom-containing cyclobutene represented by the general formula (1) can be reduced.

The composition containing the halogen atom-containing cyclobutene represented by the general formula (1) of the present disclosure can be effectively used to form the same as the case of the halogen atom-containing cyclobutene represented by the general formula (1) alone. Etching gas for cutting-edge microstructures such as semiconductors and liquid crystals, and various applications such as deposition gas, structural components for organic synthesis, and cleaning gas.

The aforementioned deposition gas system means a gas for depositing the etch-resistant polymer layer.

The aforementioned building block for organic synthesis means a substance that can become a precursor of a compound having a highly reactive skeleton. For example, when cyclobutene containing a halogen atom represented by the general formula (1) of the present disclosure, and a composition containing the same, are reacted with a fluorine-containing organosilicon compound such as CF ₃ Si(CH ₃ ) ₃ , the introduction of A fluoroalkyl group such as a CF ₃ group can be converted into a detergent or a substance that can become a fluorine-containing pharmaceutical intermediate.

The embodiment of the present disclosure has been described above, but various changes in form and detail can be added as long as they do not depart from the gist and scope of the scope of the patent application. [Example]

The following examples are given to specifically illustrate the present disclosure, but the present disclosure is not limited by these examples.

EXAMPLES In the method for producing cyclobutene containing a halogen atom of the embodiment, the raw material compound is prepared as the cyclobutane containing a halogen atom represented by the general formula (2), X ¹ , X ² , X ³ , X ⁴ and X ⁶ is a fluorine atom, X ⁵ is a hydrogen atom, and Y is a fluorine atom.

According to the following reaction formula, the desorption reaction utilizes a dehydrofluorination reaction.

The target compound is prepared as a halogen atom-containing cyclobutene represented by the general formula (1), wherein X ¹ , X ² , X ³ and X ⁴ are fluorine atoms, and Y is a fluorine atom.

In addition, in the above-mentioned desorption reaction, the following compounds may be produced as impurities.

Examples 1 to 3 (chromium oxide catalyst) A SUS pipe (outer diameter: 1/2 inch) was used as a reaction tube, and 10 g of chromium oxide containing Cr ₂ O ₃ as a main component was filled as a catalyst. As a treatment before using the aforementioned catalyst for the desorption reaction (dehydrofluorination reaction), anhydrous hydrogen fluoride was circulated in the reactor, and the temperature of the reactor was raised from 200°C to 300°C to perform the fluorination treatment. The fluorinated chromium oxide is taken out and used in the dehydrofluorination reaction. The BET specific surface area of the fluorinated chromium oxide was 75 m ² /g.

To the SUS piping (outer diameter: 1/2 inch) of the reactor, 10 g of fluorinated chromium oxide (fluorinated chromium oxide) as a catalyst was added. Under nitrogen atmosphere, after drying at 200°C for 2 hours, the pressure is normal pressure, and the contact time (W/F ₀ ) of cC ₄ F ₆ H ₂ (raw material compound) and fluorinated chromium oxide (catalyst) becomes 20 g The raw material compound (cC ₄ F ₆ H ₂ ) was circulated in the reactor in the manner of ･sec/cc or 40g･sec/cc.

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

The reactor was heated at 250°C or 350°C and the dehydrofluorination reaction started.

The dehydrofluorination reaction was started until 1 hour later, and the distillate passing through the detoxification tower was collected.

After that, mass analysis was performed by gas chromatography/mass spectrometry (GC/MS) using a gas chromatograph (manufactured by Shimadzu Corporation, trade name "GC-2014"), and mass analysis was performed using NMR (manufactured by JEOL Corporation, trade name "GC-2014"). Name "400YH") was subjected to structural analysis using NMR spectroscopy.

From the results of mass analysis and structural analysis, it was confirmed that cC ₄ F ₅ H was produced as the target compound. In Example 1, the conversion rate from cC ₄ F ₆ H ₂ (raw compound) was 3.34 mol %, and the selectivity (yield) of cC ₄ F ₅ H (object compound) was 45.9 mol %. In Example 2, conversion rate: 29.1 mol%, selectivity: 98.6 mol%. In Example 3, conversion rate: 26.1 mol%, selectivity: 97.2 mol%.

Examples 4 and 5 (alumina catalyst) Following the experimental method of the aforementioned Example 1, alumina with Al ₂ O ₃ as the main component was used as the catalyst. Following the experimental method of Example 1, the contact time (W/F ₀ ) of cC ₄ F ₆ H ₂ (raw compound) and alumina (catalyst) was 10g･sec/cc or 40g･sec/cc , so that the raw material compound is circulated in the reactor. Following the experimental method of Example 1 above, the reactor was heated at 400°C and the dehydrofluorination reaction was started. Except for the above-mentioned conditions, the dehydrofluorination reaction, mass analysis, and structural analysis were carried out in the same manner as in Example 1.

From the results of mass analysis and structural analysis, it was confirmed that cC ₄ F ₅ H was produced as the target compound. In Example 4, the conversion rate from cC ₄ F ₆ H ₂ (raw compound) was 7.92 mol %, and the selectivity of cC ₄ F ₅ H (object compound) was 45.1 mol %. In Example 5, conversion rate: 4.11 mol%, selectivity: 35.0 mol%.

Examples 6 to 10 (Activated carbon catalyst) Following the experimental method of the aforementioned Example 1, activated carbon was used as a catalyst. Following the experimental method of Example 1, the contact time (W/F ₀ ) of cC ₄ F ₆ H ₂ (raw compound) and activated carbon (catalyst) was 10g･sec/cc, 27g･sec/cc or 47g ･Sec/cc method, the raw material compound is circulated in the reactor. Following the experimental method of Example 1 above, the reactor was heated at 300°C, 350°C or 400°C and the dehydrofluorination reaction was started. Except for the above-mentioned conditions, the dehydrofluorination reaction, mass analysis, and structural analysis were carried out in the same manner as in Example 1.

From the results of mass analysis and structural analysis, it was confirmed that cC ₄ F ₅ H was produced as the target compound. In Example 6, the conversion rate from cC ₄ F ₆ H ₂ (raw material compound) was 57.6 mol %, and the selectivity of cC ₄ F ₅ H (object compound) was 95.3 mol %. In Example 7, conversion rate: 97.7 mol%, selectivity: 68.3 mol%. In Example 8, conversion rate: 84.1 mol%, selectivity: 83.8 mol%. In Example 9, conversion rate: 72.3 mol%, selectivity: 94.6 mol%. In Example 10, the conversion rate: 84.7 mol%, and the selectivity: 95.7 mol%.

The results of each example are shown in Table 1 below. In Table 1, the contact time (W/F ₀ ) means the speed at which the circulating raw material gas system is released, that is, the time during which the catalyst and the raw material gas are brought into contact.

Claims (3)

A method for producing cyclobutene represented by general formula (1), which comprises the step of de-reacting cyclobutane represented by general formula (2), and is carried out in a gas phase in the presence of a catalyst the steps of the aforementioned disengagement reaction;

In the formula, X ¹ , X ² , X ³ and X ⁴ identically or differently represent a hydrogen atom, a halogen atom, or a perfluoroalkyl group, and Y represents a halogen atom;

In the formula, X ¹ , X ² , X ³ , X ⁴ and Y are the same as the above, X ⁵ and X ⁶ are the same or different represent a hydrogen atom, a halogen atom, or a perfluoroalkyl group; the aforementioned catalyst is selected from At least one catalyst grouped from the following (i) to (iii); (i) activated carbon; (ii) selected from the group consisting of chromium oxide, fluorided chromium oxide, chromium fluoride, aluminum oxide, fluorided aluminum oxide, oxide At least one metal catalyst consisting of iron, fluorinated iron oxide, nickel oxide, fluorided nickel oxide, magnesium oxide and magnesium oxide fluoride; (iii) a metal catalyst supported on a carrier; the carrier is selected from At least one kind of carbon, alumina, zirconia, silicon dioxide, and titanium oxide group, the carbon is at least one kind of carbon selected from the group of activated carbon, amorphous carbon, graphite and diamond; the aforesaid is carried on The metal catalyst of the carrier is selected from the group consisting of chromium oxide, fluorinated chromium oxide, chromium fluoride, aluminum oxide, fluorided aluminum oxide, iron oxide, fluorided iron oxide, iron fluoride, nickel oxide, fluorided nickel oxide, fluoride At least one metal catalyst consisting of nickel, magnesium oxide and magnesium oxide fluoride. The production method according to claim 1, wherein the X ⁵ is a hydrogen atom, the X ⁶ is a halogen atom, and the desorption reaction is a dehydrohalogenation reaction. The production method according to claim 1 or 2, wherein the desorption reaction step is carried out in a gas-phase continuous flow system.