JP7259764B2 - Method for producing 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane and production of 1-chloro-2,3,3,4,4,5,5-heptafluoropentene Method - Google Patents

Description

The present invention provides a method for producing 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane and 1-chloro-2,3,3,4,4,5,5-hepta It relates to a method for producing fluoropentene.

1-Chloro-2,3,3,4,4,5,5 _- heptafluoro-1-pentene (CHCl= _CFCF2CF2CF2H ; HCFO- _1437dycc ) is a novel detergent, refrigerant, blowing agent, It is used as a solvent, an aerosol, or a raw material for synthesizing them. For example, 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane (CF ₂ HCF ₂ CF ₂ CF ₂ CClH ₂ , HCFC-448occc) is used to make HCFO-1437dycc used as a synthetic raw material for

As a method for producing HCFC-448occc, Non-Patent Document 1 discloses that a triethylamine complex of a polyfluorinated alcohol is reacted with thionyl chloride to obtain a polyfluoroalkylchlorosulfite, and then the polyfluoroalkylchlorosulfite is converted to diethylene glycol. is disclosed to give HCFC-448occc by reaction with an alkali metal halide such as LiCl in the presence of . In this method, since triethylamine hydrochloride precipitates in the reaction of obtaining polyfluoroalkyl chlorosulfite from polyfluorinated alcohol, filtration treatment is required to remove the precipitated salt. In addition, in the reaction to obtain HCFC-448occc from polyfluoroalkylchlorosulfite, diethylene glycol is used, so there is a problem of poor volumetric efficiency, resulting in low productivity.

In addition, Non-Patent Document 2 discloses a method of obtaining HCFC-448occc by reacting 2,2,3,3,4,4,5,5-octafluoropentanol with triphenyl phosphorus chloride. . In the above-described production method, since triphenyl phosphorus chloride remains as a solid content after the reaction, there is a problem that the post-treatment process is complicated.

Furthermore, Non-Patent Document 2 discloses a method of obtaining HCFO-1437dycc by dehydrofluorinating HCFC-448occc by reacting HCFC-448occc with sodium methoxide after obtaining HCFC-448occc as described above. It is However, in the above method, the target HCFO-1437dycc and sodium methoxide are thought to react, and as a result, the yield of HCFO-1437dycc is as low as about 50%. Hard to say.

Polyfluoroalkyl Chlorosulfites as New Polyfluorinating Agents, (Russia), 2002, 75, 7, 1162-1165 Zhurnal Organicheskoi Khimii, (Russia), 1988, Vol. 24, No. 8, pp. 1626-1633

The present invention is capable of producing 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane (HCFC-448occc) with high selectivity without complicated post-treatment steps. It is an object of the present invention to provide an efficient manufacturing method that can
In addition, the present invention uses an easily available raw material to produce 1-chloro-2,3,3,4,4,5,5-heptafluoropentene (HCFO-1437dycc) in an industrially advantageous manner. An object of the present invention is to provide an efficient method for producing HCFO-1437dycc, which can be produced with high selectivity and high yield.

The present invention provides a method for producing 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane having the structures described in the following [1] to [ 12 ] and [12] A process for the preparation of 1-chloro-2,3,3,4,4,5,5-heptafluoropentene having the described structure is provided.
[1] in the presence of at least one nitrogen-containing organic compound selected from the group consisting of N,N-dimethylformamide, dimethylacetamide, pyridine and tetramethylurea, 2,2,3,3,4,4,5, a first step of reacting 5-octafluoropentanol with thionyl chloride to produce 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite ; 5-chloro-1,1,2,2,3,3,4,4 -octafluoropentane is obtained by pyrolyzing 3,3,4,4,5,5-octafluoropentyl chlorosulfite and a second step of obtaining 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane.
[2] The 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane according to [1], wherein the reaction temperature in the first step is 0 to 70°C. manufacturing method.
[3] In the first step, the molar ratio of thionyl chloride to 2,2,3,3,4,4,5,5-octafluoropentanol (thionyl chloride/2,2,3,3,4, 5-chloro-1,1,2,2,3,3,4,4-octa according to [1] or [2], wherein 4,5,5-octafluoropentanol) is 0.1 to 5 A method for producing fluoropentane.
[4] In the first step, a predetermined amount of one of 2,2,3,3,4,4,5,5-octafluoropentanol and thionyl chloride is used as the material to be supplied, and the other is the material to be supplied. 5-chloro-1,1,2,2,3,3 according to any one of [1] to [3], which is added at a rate of 0.0015 to 5 mol/mol min as an addition amount per unit molar amount ,4,4-octafluoropentane production method.

[5] In the first step, the contact time between 2,2,3,3,4,4,5,5-octafluoropentanol and thionyl chloride is 1 to 8 hours [1] to [4] A method for producing 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane according to any one of
[6] In the first step, the mass ratio of the nitrogen-containing organic compound to 2,2,3,3,4,4,5,5-octafluoropentanol (nitrogen-containing organic compound/2,2,3, 3,4,4,5,5-octafluoropentanol) is 0.001 to 1, 5-chloro-1,1,2,2,3, according to any one of [1] to [5], A method for producing 3,4,4-octafluoropentane.
[7] 5-chloro-1,1,2,2,3,3 according to any one of [1] to [6], wherein the thermal decomposition reaction temperature is 70 to 170° C. in the second step. ,4,4-octafluoropentane production method.

[8] The 5-chloro-1,1,2,2,3,3,4,4 according to any one of [1] to [7], wherein the thermal decomposition reaction is performed in a solvent in the second step. - A process for the production of octafluoropentane.
[9] Production of 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane according to [8], wherein in the second step, the solvent is a nitrogen-containing organic compound. Method.
[10] 5-chloro-1,1,2,2,3,3,4,4 according to [8] or [9], wherein in the second step, the solvent is N,N-dimethylformamide - A process for the production of octafluoropentane.
[11] In the second step, the mass ratio of the solvent to the 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite (solvent/2,2,3,3 ,4,4,5,5-octafluoropentyl chlorosulfite ) is 0.01 to 1, 5-chloro-1,1,2,2, according to any one of [8] to [10], A method for producing 3,3,4,4-octafluoropentane.
[12] 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane is obtained by the production method according to any one of [1] to [11], and the obtained 5 -Chloro-1,1,2,2,3,3,4,4-octafluoropentane is subjected to a dehydrofluorination reaction in an aqueous base solution to obtain 1-chloro-2,3,3,4,4. ,5,5-heptafluoropentene.

In the present specification, with regard to halogenated hydrocarbons, abbreviations of the compounds are written in parentheses after the compound names, but the abbreviations are used in place of the compound names as necessary. Also, as an abbreviation, only the numbers after the hyphen (-) and the lowercase letters of the alphabet (for example, "448occc" in "HCFC-448occc" and "1437dycc" in "HCFO-1437dycc") may be used.

In addition, 1437dycc has Z- and E-isomers, which are geometric isomers, depending on the position of the substituent attached to the carbon having a double bond. In this specification, when compound names and compound abbreviations are used for compounds in which Z-isomer and E-isomer exist, Z-isomer or E-isomer, or any ratio of Z-isomer and E-isomer shows a mixture of When (Z) or (E) is attached to the end of a compound name or compound abbreviation, it indicates that the respective compound is in Z-form or E-form.

According to the method for producing 448occc of the present invention, 448occc can be efficiently produced with high selectivity without requiring a complicated post-treatment process.
According to the method for producing 1437dycc of the present invention, it is possible to produce 1437dycc with high selectivity and high yield in an industrially advantageous manner using readily available raw materials.

It is a figure which shows an example of the apparatus used for the manufacturing method of 448occc of embodiment. It is a figure which shows an example of the other apparatus used for the manufacturing method of 448occc of embodiment. It is a figure which shows an example of the reactor used for the manufacturing method of 1437dycc of embodiment.

<Method for producing 448occc>
The method for producing 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane (CF ₂ HCF ₂ CF ₂ CF ₂ CClH ₂ ) of the present embodiment will be specifically described below. .

In the method for producing 448occc of the present embodiment, at least one nitrogen-containing organic compound selected from the group consisting of N,N-dimethylformamide, dimethylacetamide, pyridine and tetramethylurea (hereinafter simply referred to as "nitrogen-containing organic compound") ), 2,2,3,3,4,4,5,5-octafluoropentanol (CF ₂ HCF ₂ CF ₂ CF ₂ CH ₂ OH, hereinafter referred to as “OFPO”) and chloride thionyl (SOCl ₂ ) to produce 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite (CF ₂ HCF ₂ CF ₂ CF ₂ CH ₂ OSOCl). 1 and a second step of thermally decomposing 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite to obtain 448occc.

The reaction of OFPO and thionyl chloride in the first step is represented by the following formula (1).

In the above reaction, together with 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite , 1-pentanol- 2,2,3,3,4,4,5,5-octafluoro-1,1-sulfite may be formed. Therefore, the products of the above reaction include 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite and by-products, if any, of the above reaction. obtained as a composition. Here, 1-pentanol-2,2,3,3,4,4,5,5-octafluoro-1,1-sulfite is 2,2,3,3,4,4,5,5 -Octafluoropentyl chlorosulfite to which one OFPO molecule is added. Hereinafter, 1-pentanol-2,2,3,3,4,4,5,5-octafluoro-1,1-sulfite is also referred to as "OFPO diadduct".

The first step is carried out in the presence of at least one nitrogen-containing organic compound selected from the group consisting of N,N-dimethylformamide, dimethylacetamide, pyridine and tetramethylurea. The nitrogen-containing organic compound has a catalytic action in the reaction of formula (1) and can promote the reaction between OFPO and thionyl chloride. As the nitrogen-containing organic compound, N,N-dimethylformamide (DMF) is preferable from the viewpoint of obtaining a sufficient reaction rate. The nitrogen-containing organic compounds may be used alone or in combination of two or more.

In the first step, the mass ratio of the nitrogen-containing organic compound to OFPO (nitrogen-containing organic compound/OFPO) is preferably 0.001-1. A sufficient reaction rate can be obtained when the mass ratio (nitrogen-containing organic compound/OFPO) is within the above range. In addition, the formation of by-products such as OFPO diadducts is suppressed, and the selectivity for 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite increases. The mass ratio (nitrogen-containing organic compound/OFPO) is more preferably 0.002 or more, even more preferably 0.005 or more, from the viewpoint of further suppressing the formation of OFPO diadducts and the like. Also, the mass ratio (nitrogen-containing organic compound/OFPO) is more preferably 0.5 or less, and even more preferably 0.1 or less.

In the first step, the molar ratio of thionyl chloride to OFPO (thionyl chloride/OFPO) is preferably 0.1-5. When the molar ratio (thionyl chloride/OFPO) is within the above range, the formation of by-products such as OFPO diadduct is suppressed, and 2,2,3,3,4,4,5,5-octafluoro Increased selectivity for pentyl chlorosulfite . The molar ratio (thionyl chloride/OFPO) is more preferably 0.3 or more, still more preferably 0.5 or more, and particularly preferably 0.8 or more, in order to increase the conversion rate of the starting materials. Further, the molar ratio (thionyl chloride/OFPO) is more preferably 4 or less.

1st process WHEREIN: It is preferable that reaction temperature is 70 degrees C or less. If the reaction temperature is 70° C. or lower, the conversion of OFPO and the selectivity of 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite are improved.

Moreover, in the first step, the reaction temperature is preferably 0° C. or higher. A sufficient reaction rate can be obtained when the reaction temperature is 0° C. or higher. The reaction temperature in the first step is preferably 20° C. or higher, and more preferably 30° C. or higher, in order to allow the reaction to proceed effectively and increase the reaction rate.

If the reaction proceeds rapidly, a large amount of hydrogen chloride gas is generated, and the pressure inside the reactor rises, possibly damaging the reactor. In addition, when a large amount of hydrogen chloride gas is generated, raw materials such as OFPO and thionyl chloride, and 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite are expelled from the reactor together with hydrogen chloride gas. may be discharged into

From the above, the first step is preferably carried out at a reaction temperature of 0°C to 70°C, more preferably 30°C to 70°C. Within this range, the reaction proceeds effectively and 2,2,3,3,4,4,5,5-octafluoropentyl chlorosulfite can be obtained with high selectivity.

The first step may be performed batchwise or continuously. When the first step is performed in batch mode, a predetermined amount of one of OFPO and thionyl chloride is placed in a reactor as a material to be supplied, and the other is gradually added to the material to be supplied in the reactor. be able to. In the first step, for example, a predetermined amount of thionyl chloride is placed in a reactor, and OFPO is gradually added to thionyl chloride, or a predetermined amount of OFPO is reacted. This can be done by placing in a vessel and gradually adding thionyl chloride to OFPO. At this time, the nitrogen-containing organic compound is preferably premixed with OFPO or thionyl chloride. The nitrogen-containing organic compound may be mixed with either OFPO or thionyl chloride in all predetermined amounts. Further, the nitrogen-containing organic compound may be mixed by dividing a predetermined amount into OFPO and thionyl chloride.

In addition, when the first step is performed batchwise as described above, the other compound of OFPO and thionyl chloride is added to a supplied material consisting of a predetermined amount of either OFPO or thionyl chloride. The rate is preferably 0.0015 to 5 mol/mol·min as the amount added per unit mol (1 mol) of the substance to be supplied. If the addition rate is 0.0015 mol / mol · min or more, the reaction can be sufficiently advanced, and if the addition rate is 5 mol / mol · min or less, the formation of by-products such as OFPO diadducts is suppressed. can be suppressed. The addition rate is more preferably 0.0125 mol/mol·min or more, and more preferably 1.5 mol/mol·min or less.

When the first step is carried out in a continuous manner, OFPO, thionyl chloride, and a nitrogen-containing organic compound are continuously supplied into the reactor at a predetermined molar ratio at a predetermined supply rate, and these are placed in the reactor at a predetermined rate. It can be done in contact for hours. In this case, the nitrogen-containing organic compound is preferably premixed with OFPO or thionyl chloride and fed into the reactor from the viewpoint of operational efficiency. When the first step is carried out continuously, the feed rate of OFPO, thionyl chloride and nitrogen-containing organic compound to the reactor is adjusted by the feed flow rate of each compound.

When the first step is performed continuously, the supply rate of OFPO into the reactor is 0.0015 to 5 mol / mol min with respect to the amount (molar amount) of thionyl chloride supplied per minute. Alternatively, the supply rate of thionyl chloride is 0.0015 to 5 mol/mol min with respect to the amount (molar amount) of OFPO supplied per minute. is preferred.

The reaction time in the first step is, for example, 1 to 8 hours, depending on the amounts of OFPO and thionyl chloride. The reaction time in the first step is represented by the contact time between OFPO and thionyl chloride. For example, as described above, the first step is performed batchwise, a predetermined amount of one of OFPO and thionyl chloride is accommodated in the reactor as a feed, and the other is gradually added to the feed in the reactor. When one of OFPO and thionyl chloride is used as a to-be-supplied material, it is the time from the start of supply of the other to the end of the reaction when generation of hydrogen chloride gas ceases. When the first step is performed continuously, the reaction time is the residence time of OFPO and thionyl chloride in the reactor.

When water is present in the reaction system between OFPO and thionyl chloride, the reaction between thionyl chloride and water decomposes thionyl chloride into sulfur dioxide and hydrogen chloride. Also, when water is present in the reaction system, 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite decomposes into OFPO, sulfur dioxide and hydrogen chloride. Therefore, in order to suppress these decompositions, it is preferable to reduce water in the reaction system as much as possible. As a method for reducing water, for example, there is a method of replacing the atmosphere of the reaction system with a dry gas. The water content is preferably 1000 ppm by mass or less, more preferably 500 ppm by mass or less, and even more preferably 100 ppm by mass or less, relative to the total amount of OFPO.

In addition, from the viewpoint of increasing the selectivity of 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite in the reaction between OFPO and thionyl chloride, it should not contain any alcohol other than OFPO. is preferred. The amount of alcohol other than OFPO is preferably 1000 ppm by mass or less, more preferably 500 ppm by mass or less, and even more preferably 100 ppm by mass or less relative to the total amount of OFPO.

OFPO and nitrogen-containing organic compounds are sometimes mixed with moisture (humidity) in the atmosphere during storage, for example, and exist in the form of a mixture of OFPO and water or a mixture of nitrogen-containing organic compounds and water. Even in such a case, for the same reason as described above, the amount of water contained in the mixture of OFPO and water or the mixture of nitrogen-containing organic compound and water is reduced as much as possible before OFPO and nitrogen-containing organic compound are supplied to the reactor. preferably. As a method for reducing water, for example, water is removed by contacting a mixture of OFPO and water or a mixture of nitrogen-containing organic compound and water with a drying agent such as zeolite or silica, or a mixture of OFPO and water and nitrogen-containing A method of removing water by contacting a drying agent such as zeolite or silica after mixing a mixture of an organic compound and water can be mentioned.

When water is removed from a mixture of OFPO and water and a mixture of nitrogen-containing organic compound and water, respectively, the amount of water in the mixture of OFPO and water or the mixture of nitrogen-containing organic compound and water is It is preferably 1000 ppm by mass or less, more preferably 500 ppm by mass or less, and even more preferably 100 ppm by mass or less relative to the amount (the amount of OFPO or the amount of nitrogen-containing organic compound). In addition, when water is removed by mixing a mixture of OFPO and water and a mixture of nitrogen-containing organic compounds and water, the amount of water in the mixture of OFPO, nitrogen-containing organic compounds and water is the total amount of OFPO and nitrogen-containing organic compounds. It is preferably 1000 ppm by mass or less, more preferably 500 ppm by mass or less, and even more preferably 100 ppm by mass or less (total amount of OFPO and DMF).

In a first step a composition comprising 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite is obtained. The composition containing 2,2,3,3,4,4,5,5-octafluoropentyl chlorosulfite may contain, for example, a nitrogen-containing organic compound, unreacted raw materials OFPO and thionyl chloride. It may also contain an OFPO diadduct as a by-product.

Further, when DMF is used as the nitrogen-containing organic compound in the first step, the composition containing 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite obtained in the first step containing a compound represented by the following formula (3) obtained by reacting part or all of 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite with DMF There is Hereinafter, 2,2,3,3,4,4,5,5-octafluoropentyl chlorosulfite is also referred to as "intermediate". In addition, the compound represented by formula (3) is also referred to as "intermediate-DMF adduct". In the second step, the intermediate-DMF adduct is presumed to be thermally decomposed to form 448occc.

In a second step, 448occc is obtained by pyrolysis of 2,2,3,3,4,4,5,5 -octafluoropentylchlorosulfite .

In a second step, only 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite may be pyrolyzed, the 2,2, It may be pyrolyzed in a composition containing 3,3,4,4,5,5- octafluoropentyl chlorosulfite .

In the second step, 2,2,3,3,4,4,5,5 -octafluoropentylchlorosulfite is thermally decomposed to produce 448occc as shown in formula (4) below. Specifically, 448occc is produced by desulfurization reaction.

The thermal decomposition temperature is preferably 70° C. or higher. When the temperature is 70° C. or higher, thermal decomposition of 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite is accelerated. From the viewpoint of further promoting thermal decomposition, the temperature is preferably 80°C or higher, more preferably 100°C or higher, and from the viewpoint that the reaction rate and the conversion rate of intermediates can be increased, the temperature is particularly preferably higher than 110°C, and most preferably 115°C or higher. . In addition, the pyrolysis temperature can be suppressed to prevent volatilization of 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite before pyrolysis, improving the yield of 448 occc. 170° C. or less is preferable because the temperature can be reduced. The thermal decomposition temperature means the temperature in the reactor where thermal decomposition is performed, more specifically, the temperature of the liquid phase in the reactor.

Furthermore, when DMF is used as the nitrogen-containing organic compound, if the reaction temperature is 170° C. or higher, DMF decomposes into formic acid, and formic acid becomes 2,2,3,3,4,4,5,5-octafluoropentene. 2,2,3,3,4,4,5,5- octafluoropentyl formate represented by the following formula (5) is produced as a by-product by reacting with chyl chlorosulfite. The reaction temperature is preferably 170° C. or lower also from the viewpoint of suppressing the production of this by-product. Hereinafter, 2,2,3,3,4,4,5,5-octafluoropentylformate is referred to as "intermediate-formic acid adduct".

In the second step, pyrolysis is preferably carried out in the presence of a solvent. The use of a solvent can facilitate the production of 448occc. The solvent is a compound that can dissolve 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite and 448occc and is inert in the reaction of formula (4) above. As the solvent, the aforementioned nitrogen-containing organic compounds can be used, and specifically, DMF, tetramethylurea, dimethylacetamide, pyridine and the like can be used. Among them, DMF is particularly preferable because 448occc can be efficiently obtained. As the solvent, it is preferable to use the same compound as the nitrogen-containing organic compound used in the first step.

In the second step, if the pyrolysis is carried out in the presence of a solvent, the mass ratio of solvent to 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite (solvent/2, 2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite ) is preferably 0.01-1. If the amount of the solvent is within the above range, the production of 448occc can be further promoted, and 448occc can be obtained in high yield.

The pyrolysis in the second step may be performed batchwise or continuously. From the viewpoint of production efficiency, it is preferable to carry out in a continuous manner. The thermal decomposition pressure in the second step may be normal pressure, reduced pressure or increased pressure.

When the second step is performed batchwise, it depends on the amount of 2,2,3,3,4,4,5,5-octafluoropentyl chlorosulfite to be thermally decomposed and the feed rate. For example, it is preferable to carry out the pyrolysis in 1 to 40 hours.

In a second step a composition containing 448occc can be obtained. The obtained composition containing 448occc contained the target 448occc, as well as unreacted 2,2,3,3,4,4,5,5 -octafluoropentylchlorosulfite , OFPO, and OFPO2. Adducts such as hydrogen chloride and sulfur dioxide may be included. When DMF is used as the nitrogen-containing organic compound or solvent, the composition containing 448occc may contain DMF, intermediate-DMF adducts, intermediate-formic acid adducts, and the like.

To neutralize the hydrogen chloride and sulfur dioxide in the composition containing 448occc, it is preferred to contact the composition containing 448occc with an aqueous alkaline solution. Examples of the alkaline aqueous solution used at this time include an aqueous sodium hydroxide solution and an aqueous potassium hydroxide solution. After contact with the aqueous alkaline solution, the composition containing 448occc separates into an organic phase and an aqueous phase. Since 448occc is contained in the organic phase, 448occc can be obtained by separating and recovering the organic phase.

In order to neutralize impurities, the method of contacting the composition containing 448 occc with an alkaline aqueous solution as described above can be carried out in the absence of a phase transfer catalyst or a water-soluble organic solvent for a short period of time. preferable. As a result, 448occc itself does not sufficiently come into contact with the alkaline aqueous solution, and the dehydrofluorination reaction in which 1437dycc is produced from 448occc can be suppressed by contacting with the alkaline aqueous solution described later.

In a second step pyrolysis of 2,2,3,3,4,4,5,5- octafluoropentyl chlorosulfite yields 2,2,3,3,4,4,5,5 - The conversion rate of octafluoropentyl chlorosulfite can be 50% or more.

Moreover, according to the present invention, the selectivity of 448 occc can be increased to 50% or higher through the second step. Here, the selectivity (%) of 448occc means the ratio of the molar amount of 448occc in the composition containing 448occc obtained in the second step to the molar amount of the intermediate consumed in the second step (( mol amount of 448occc produced)/(molar amount of intermediate consumed)×100).

In addition, when the composition containing 448occc is contacted with an aqueous alkaline solution, the selectivity of 448occc in the organic phase obtained by contacting the distillate with respect to the molar amount of the intermediate consumed in the second step with the aqueous alkaline solution of 448 occc (((moles of 448 occc)/(moles of intermediate consumed)×100).

Compounds other than 448occ contained in the organic phase, such as OFPO, OFPO diadducts, nitrogen-containing organic compounds, solvents, DMF, intermediate-DMF adducts, and intermediate-formic acid adducts can be separated by ordinary distillation. , which gives 448occc of high purity. Distillation of the composition containing 448occc may be carried out under normal pressure, under reduced pressure, or under increased pressure, preferably under reduced pressure.

Alternatively, the second step may be carried out by reactive distillation using a reactor equipped with a distillation column. By extracting high-purity 448 occc as a fraction from the top of the distillation column by reactive distillation, the load of the subsequent distillation process can be reduced. The pressure in the reactor and distillation column for reactive distillation is preferably 30 to 2000 hPa, more preferably 100 to 1500 hPa, more preferably 200 to 1100 hPa, in order to obtain 448 occc of high purity and increase the recovery amount of 448 occc. More preferred. Moreover, the recovery amount of 448 occc can be further increased by extracting and distilling the composition containing 448 occc remaining as still residue.

Through the first step, second step and distillation, the content of OFPO diadduct in the composition containing 448occc can be reduced to less than 10% by mass. The content of the OFPO diadduct is preferably 7% by mass or less, more preferably 5% by mass or less.

Moreover, according to the present invention, the content of 448occc in the resulting composition containing 448occc can be made 80% by mass or more through the first step, second step and distillation. The content of 448occc is preferably 85% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more.

The same reactor may be used for the first step and the second step, or different reactors may be used. Examples of reactors that can be used for both the first step and the second step include those having a reactor and a temperature controller.

As a reactor, OFPO and thionyl chloride can be introduced and reacted, and 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite can be thermally decomposed. Anything that can be done is good. Examples of materials for such a reactor include glass, stainless steel such as SUS, glass lining materials, and resin lining materials.

As a temperature control unit, the reaction temperature between OFPO and thionyl chloride can be adjusted, and the Anything that can adjust the temperature may be used. Such devices include an oil bath, a heater, and the like. In addition, the temperature control unit may be provided integrally with the reactor.

On the other hand, when different reactors are used for the first step and the second step, the reactor used for each step only needs to have the functions required for that step. By using different reactors for the first step and the second step, for example, an industrially used device can be used, facilitating mass production of 448 occc.

FIG. 1 shows an example of an industrially used apparatus for performing the first step in a batch manner and the second step in a continuous manner.

In FIG. 1, in the first step, a predetermined amount of thionyl chloride is placed in a reactor 11 as a material to be supplied, and a mixture of OFPO and a nitrogen-containing organic compound is continuously supplied thereto at a predetermined supply rate. Although the apparatus for performing the operation will be described as an example, it is not limited to this. The reaction apparatus 10 includes a reactor 11, a raw material supply means 12 for supplying a mixture of OFPO and a nitrogen-containing organic compound to the reactor 11, and a liquid phase after the reaction is taken out from the reactor 11 to perform the second step. and a liquid supply means 13 for supplying to the reactor 14 . The reactor 10 further comprises means 15 for removing the reacted liquid phase from the reactor 14 .

In addition, the reactors 11 and 14 are configured to adjust the temperature inside the reactors by a temperature controller (not shown). The reaction apparatus 10 includes an alkali cleaning means 16 for contacting the liquid phase after the reaction taken out from the reactor 14 with an alkaline aqueous solution, and a separating means 17 for separating the liquid phase after contacting with the alkaline aqueous solution into an organic phase and an aqueous phase. It has

In the reactor 10, a mixed solution of OFPO and a nitrogen-containing organic compound is supplied from the raw material supply means 12 into the reactor 11 with thionyl chloride contained in the reactor 11 at a predetermined supply flow rate. is added to The supply flow rate of the mixture of OFPO and the nitrogen-containing organic compound can be automatically controlled by installing a mass flow controller or the like. In the reactor 11, thionyl chloride and OFPO react in the presence of a nitrogen-containing organic compound to produce 2,2,3,3,3,4,4,5,5 -octafluoropentylchlorosulfite . The liquid phase composed of the composition containing the produced 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite is then supplied to the reactor 14 by the liquid supply means 13. .

In the reactor 14, a composition containing 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite is heated to a predetermined temperature by a temperature controller (not shown), and 2,2 ,3,3,4,4,5,5 -octafluoropentyl chlorosulfite is thermally decomposed to produce 448occc. The liquid phase composed of the composition containing the produced 448occc is taken out from the reactor 14 by the liquid feeding means 15, passed through the alkali cleaning means 16 and brought into contact with the alkaline aqueous solution, and then separated by the separation means 17 into the organic phase and the water. The phases are separated. 448occc, which is the desired product, can be obtained in the separated organic phase.

FIG. 2 shows an example of an industrially used apparatus which is used when both the first step and the second step are performed in a continuous manner.

The reaction apparatus 20 shown in FIG. 2 includes a reactor 21 for performing the first step, a raw material supply means 22a for supplying thionyl chloride to the reactor 21, a raw material supply means 22b for supplying OFPO, and a nitrogen-containing organic compound. A raw material supply means 22c for supplying is provided. In addition, the reactor 20 is provided with liquid supply means 23 for extracting the liquid phase after the reaction from the reactor 21 and supplying it to the reactor 24 for performing the second step. The reactor 20 further comprises means 25 for removing the reacted liquid phase from the reactor 24 .

In addition, the reactors 21 and 24 are configured to adjust the temperature inside the reactors by a temperature controller (not shown). The reaction apparatus 20 includes an alkali cleaning means 26 for contacting the liquid phase after the reaction taken out from the reactor 24 with an alkaline aqueous solution, and a separation means 27 for separating the liquid phase after being contacted with the alkaline aqueous solution into an organic phase and an aqueous phase. It has

Thionyl chloride, OFPO and a nitrogen-containing organic compound are supplied into the reactor 21 at a predetermined supply flow rate by raw material supply means 22a to 22c. At this time, the nitrogen-containing organic compound may be mixed with any one of thionyl chloride and OFPO and supplied to the reactor 21 . The flow rate of thionyl chloride, OFPO, and nitrogen-containing organic compound supplied to the reactor 21 can be automatically controlled by installing a mass flow controller or the like, for example. In the reactor 21, thionyl chloride and OFPO react in the presence of a nitrogen-containing organic compound to produce 2,2,3,3,3,4,4,5,5 -octafluoropentylchlorosulfite . The liquid phase composed of the composition containing the produced 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite is then supplied to the reactor 24 by the liquid supply means 23. .

In the reactor 24, a composition containing 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite is heated to a predetermined temperature by a temperature controller (not shown), and 2,2 ,3,3,4,4,5,5 -octafluoropentyl chlorosulfite is thermally decomposed to produce 448occc. The liquid phase composed of the composition containing the generated 448 occc is taken out from the reactor 24 by the liquid feeding means 25, passed through the alkaline cleaning means 26 and brought into contact with the alkaline aqueous solution, and then separated by the separating means 27 into an organic phase and an aqueous phase. separated into
448 occc, which is the desired product, can be obtained in the separated organic phase.

<Method for producing 1437dycc>
The method for producing 1-chloro-2,3,3,4,4,5,5-heptafluoropentene (1437dycc) of the present invention is the method of the present invention described above, wherein 5-chloro-1,1,2, 2,3,3,4,4-Octafluoropentane (448occc) is obtained, and the obtained 448occc is subjected to a dehydrofluorination reaction in an aqueous base solution to obtain 1437dycc.

The reaction according to the method for producing 1437dycc of this embodiment is represented by the following formula (6).

1437dycc obtained by the production method of the present embodiment has a high proportion of halogen that suppresses combustibility, and has a carbon-carbon double bond in the molecule that is easily decomposed by OH radicals in the atmosphere. low, low impact on the ozone layer, and low impact on global warming. Therefore, it is highly useful as a solvent and a working medium (a heat medium used for heat exchange, a working medium used for a heat cycle system, etc.).

1437dycc obtained by the production method of the present embodiment may be only the Z-isomer, only the E-isomer, or a mixture of the Z-isomer and the E-isomer. 1437dycc(Z), which is the Z-isomer, has higher chemical stability than 1437dycc(E), which is the E-isomer, and is more preferable as a solvent or working medium. According to the manufacturing method of the present embodiment, 1437dycc including 1437dycc(Z) can be efficiently manufactured. Furthermore, according to the production method of the present embodiment, 1437dycc having a higher content of 1437dycc (Z) than 1437dycc (E) can be obtained.

In the method for producing 1437dycc of the present embodiment, as described above, 448occc is subjected to a dehydrofluorination reaction in an aqueous base solution according to the reaction represented by formula (6) (hereinafter referred to as reaction (6)). is.

The starting material for reaction (6) may contain 448occc, and for example, 448occc obtained by the method for producing 448occc in the above embodiment can be used. The crude liquid containing 448occc obtained by the method for producing 448occc of the above embodiment may be used as it is, or the crude liquid may be purified by a known method before use. From the viewpoint of economy, the starting material for reaction (6) may contain impurities such as by-products other than 448occc in the method for producing 448occc and unreacted raw materials. Conceptually preferred. Impurities are preferably compounds that do not interfere with the dehydrofluorination reaction of 448occc. Examples of impurities include 1437dycc, OFPO, DMF, and the like.

When the starting material contains impurities, the ratio of 448occc to the total amount of impurities and 448occc is preferably 85% by mass or more and less than 100% by mass, more preferably 90% by mass or more and 99% by mass or less.

Further, when the starting material for reaction (6) contains at least one compound selected from 1437dycc, OFPO and DMF, the ratio of the total amount of 1437dycc, OFPO and DMF is More than 0 mass % and 15 mass % or less are preferable, and 0.1 mass % or more and 7 mass % or less are more preferable with respect to the total amount.

When the starting material for reaction (6) contains OFPO, the content of OFPO is preferably more than 0% by mass and 3% by mass or less relative to the total amount of the starting material, and 0.1% by mass or more and 1% by mass or less. more preferred. If the content of OFPO is within the above range, the production cost can be suppressed and the selectivity of 1437dycc is further improved.

The base in reaction (6) is not particularly limited as long as it is a base capable of performing the dehydrofluorination reaction of reaction (6). The base is preferably at least one selected from the group consisting of metal hydroxides, metal oxides and metal carbonates.

Examples of metal hydroxides include alkaline earth metal hydroxides and alkali metal hydroxides. Preferred alkaline earth metal hydroxides are magnesium hydroxide, calcium hydroxide, strontium hydroxide and barium hydroxide, and preferred alkali metal hydroxides are lithium hydroxide, sodium hydroxide and potassium hydroxide. 1 type may be sufficient as a metal hydroxide and 2 or more types may be sufficient as it.

Examples of metal oxides include alkali metal oxides and alkaline earth metal oxides. Sodium oxide is preferred as the alkali metal oxide, and calcium oxide is preferred as the alkaline earth metal oxide. The metal oxide may be of one kind, two or more kinds, or a composite oxide of two or more kinds of metals.

Examples of metal carbonates include alkali metal carbonates and alkaline earth metal carbonates. Alkali metal carbonates include carbonates of lithium, sodium, potassium, rubidium, cesium or francium. Alkaline earth metal carbonates include beryllium, magnesium, calcium, strontium, barium or radium carbonates. One type of metal carbonate may be used, or two or more types may be used.

Among the above bases, it is preferable to use metal hydroxides. At least one selected from potassium hydroxide and sodium hydroxide is preferable as the metal hydroxide. Potassium hydroxide or sodium hydroxide may be used alone, or potassium hydroxide and sodium hydroxide may be used in combination.

The amount of base relative to 448occc is preferably 0.5 to 10 mol, more preferably 0.5 to 5.0 mol, relative to 1 mol of 448occc, from the viewpoint of improving the conversion rate of 448occc and the selectivity of 1437dycc. More preferably 0.5 to 2.5 mol, most preferably 0.5 to 2.0 mol.

In reaction (6), the base is used as an aqueous solution of the base. As the aqueous solution of the base, an aqueous alkali metal hydroxide solution is preferable, and an aqueous sodium hydroxide solution or an aqueous potassium hydroxide solution is more preferable.

The amount of base relative to the total amount of aqueous solution of base is preferably 0.5 to 40% by mass, more preferably 10 to 40% by mass. When the amount of the base relative to the total amount of the aqueous solution of the base is at least the above lower limit, a sufficient reaction rate can easily be obtained, and the target substance can be easily separated by two-layer separation. If the content is equal to or less than the above upper limit, the base is easily dissolved sufficiently and the metal salt is less likely to precipitate, which is likely to be advantageous in industrial processes. Further, the amount of the base relative to the total amount of the aqueous solution of the base is more preferably 20 to 38% by mass, most preferably 20 to 35% by mass. If the amount of the base to the total amount of the aqueous solution of the base is 20% by mass or more, the conversion rate of 448 occc will be higher and the reaction rate will be faster.

FIG. 3 shows an example of an apparatus (reaction apparatus 30) industrially used in the 1437dycc production method of the present embodiment.

In the production method of the present embodiment, as shown in FIG. 3, 448 occc of the basic aqueous solution and, if necessary, other compounds involved in the reactions contained in the raw material tank (indicated by reference numeral 32) are contained in advance. It is supplied to the reactor 31 and reacted. The composition containing 1437dycc produced is recovered from the reactor 31 and cooled via the cooler 33 as required. Furthermore, it is preferable to recover from the inside of the recovery tank 35 which accommodates the product which passed through the dehydration tower 34 as needed, and water was removed.

As the reactor 31, a known reactor used for dehydrofluorination reaction in a liquid phase reaction is preferable. Examples of materials for the reactor 31 include iron, nickel, alloys containing these as main components, and glass. If necessary, the reactor 31 may be lined with resin lining, glass lining, or the like. In addition, it is preferable to provide a stirring means in the reactor 31 and perform the reaction while stirring so that the reaction is performed in a state in which the raw materials, the product, the base, the solvent, and the like are uniformly distributed in the reaction system.

Here, the reaction temperature in reaction (6) is preferably 0 to 80°C, more preferably 0 to 60°C, even more preferably 10 to 50°C, and particularly preferably 20 to 40°C. By setting the reaction temperature within the above range, the formation of by-products can be suppressed, the conversion rate of 448 occc can be improved, and the yield and selectivity of 1437 dycc can be improved. Furthermore, among the 1437dycc isomers, the Z-isomer can also be selectively obtained. Here, the reaction temperature is the temperature within the reactor, more specifically the temperature of the liquid phase within the reactor. In the apparatus shown in FIG. 3, the temperature inside the reactor 31 is the reaction temperature.

The pressure in the reactor during the reaction is not particularly limited, but is preferably −0.1 to 10 MPa, more preferably 0 to 5 MPa, and even more preferably 0 to 1 MPa. The pressure in the reactor is preferably above the vapor pressure of 448 occc at the reaction temperature.

Reaction (6) can be carried out in a semi-continuous, batch or continuous manner. Incidentally, the reaction time can be appropriately adjusted by a general method for each system. The reaction time is preferably 1 to 50 hours in a batch system, and preferably 1 to 20 hours in a continuous system, since the conversion rate of 448 occc and the selectivity of 1437 dycc, which are raw materials, can be easily controlled. In the case of the continuous system, the residence time of the raw materials in the reactor is regarded as the reaction time.

Reaction (6) is preferably carried out in the presence of a phase transfer catalyst so that the raw material 448 cc and the aqueous solution of the base can efficiently contact each other. Further, the reaction may be carried out in the presence of a water-soluble organic solvent such as tetraglyme as long as it does not affect the reaction. A phase transfer catalyst is preferably used to speed up the reaction.

Phase transfer catalysts include quaternary ammonium salts, quaternary phosphonium salts, quaternary arsonium salts, sulfonium salts, crown ethers, etc., and quaternary ammonium salts, quaternary phosphonium salts, quaternary arsonium salts, and the like. A salt, a sulfonium salt, is preferred, and a quaternary ammonium salt is more preferred.

Quaternary ammonium salts include compounds represented by the following formula (i).

（ただし、式（ｉ）中、Ｒ^１１～Ｒ^１４は、それぞれ独立して、１価の炭化水素基、又は反応に不活性な官能基が結合した１価の炭化水素基を表し、Ｙ^１－は、１価の陰イオンを表す。）

(In formula (i), R ¹¹ to R ¹⁴ each independently represent a monovalent hydrocarbon group or a monovalent hydrocarbon group to which a functional group inert to the reaction is bonded, and Y ^{1 -} represents a monovalent anion.)

When R ¹¹ to R ¹⁴ are hydrocarbon groups, examples thereof include alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups and aryl groups, with alkyl groups and aryl groups being preferred. The number of carbon atoms in each of R ¹¹ to R ¹⁴ is preferably 1-100, more preferably 4-30. R ¹¹ to R ¹⁴ may each be the same group or different groups.

When R ¹¹ to R ¹⁴ are monovalent hydrocarbon groups to which a functional group inert to the reaction is bonded, the functional group may be appropriately selected depending on the reaction conditions. groups, nitrile groups, acyl groups, carboxyl groups, alkoxyl groups, and the like.

The quaternary ammonium (R ¹¹ R ¹² R ¹³ R ¹⁴ N ⁺ ) in the above formula (i) includes tetramethylammonium, tetraethylammonium, tetra-n-propylammonium, tetra-n-butylammonium, methyltri-n- Octylammonium, cetyltrimethylammonium, benzyltrimethylammonium, benzyltriethylammonium, cetylbenzyldimethylammonium, cetylpyridinium, n-dodecylpyridinium, phenyltrimethylammonium, phenyltriethylammonium, N-benzylpicolinium, pentamethonium, hexamethonium, etc. is mentioned.

Y ^1- in the above formula (i) includes fluorine ion, chloride ion, bromide ion, iodine ion, sulfate ion, nitrate ion, phosphate ion, perchlorate ion, hydrogen sulfate ion, hydroxide ion, and acetate ion. , benzoate ion, benzenesulfonate ion, p-toluenesulfonate ion, etc., preferably fluorine ion, chloride ion, bromide ion, iodine ion, hydrogen sulfate ion, hydroxide ion, fluorine ion, chloride ion, Bromine ions, iodine ions, and hydroxide ions are more preferred, and chloride ions and bromine ions are even more preferred.

As the compound represented by the above formula (i), from the viewpoint of versatility and reactivity, a combination of the following quaternary ammonium (R ¹¹ R ¹² R ¹³ R ¹⁴ N ⁺ ) and Y ^1- below is preferable. .
Quaternary ammonium (R ¹¹ R ¹² R ¹³ R ¹⁴ N ⁺ ): tetramethylammonium, tetraethylammonium, tetra-n-propylammonium, tetra-n-butylammonium, methyltri-n-octylammonium.
Y ¹⁻ : fluorine ion, chloride ion, bromide ion, iodine ion, hydroxide ion.

The quaternary ammonium salts include tetra-n-butylammonium chloride (TBAC), tetra-n-butylammonium bromide (TBAB), methyltri-n-octylammonium, in terms of industrial availability, price, and ease of handling. It is preferably at least one selected from the group consisting of chloride (TOMAC).

The quaternary phosphonium salts include compounds represented by the following formula (ii).

（ただし、式（ii）中、Ｒ^２１～Ｒ^２４は、それぞれ独立して、１価の炭化水素基を表し、Ｙ^２－は、１価の陰イオンを表す。Ｒ^２１～Ｒ^２４は、それぞれ同じ基であってもよいし、異なる基であってもよい。）

(In formula (ii), R ²¹ to R ²⁴ each independently represent a monovalent hydrocarbon group, and Y ^2- represents a monovalent anion. R ²¹ to R ²⁴ are They may be the same group or different groups.)

Examples of hydrocarbon groups for R ²¹ to R ²⁴ include alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups and aryl groups, with alkyl groups and aryl groups being preferred.

The quaternary phosphonium (R ²¹ R ²² R ²³ R ²⁴ P ⁺ ) in the above formula (ii) includes tetraethylphosphonium, tetra-n-butylphosphonium, ethyltri-n-octylphosphonium, cetyltriethylphosphonium, cetyltri-n- Butylphosphonium, n-butyltriphenylphosphonium, n-amyltriphenylphosphonium, methyltriphenylphosphonium, benzyltriphenylphosphonium, tetraphenylphosphonium and the like.

Y ^2- includes chloride ion, fluoride ion, bromide ion, iodine ion, sulfate ion, nitrate ion, phosphate ion, perchlorate ion, hydrogen sulfate ion, hydroxide ion, acetate ion, benzoate ion, benzene Examples include sulfonate ions and p-toluenesulfonate ions, and fluorine ions, chloride ions, and bromine ions are preferred.
The quaternary phosphonium salt is preferably at least one selected from the group consisting of tetra-n-butylphosphonium chloride and tetra-n-butylphosphonium fluoride from the standpoint of industrial availability.

Examples of quaternary arsonium salts include compounds represented by the following formula (iii).

ただし、式（iii）中、Ｒ^３１～Ｒ^３４は、式（ii）におけるＲ^２１～Ｒ^２４と同様であり、好ましい態様も同様である。Ｙ^３－は１価の陰イオンを表す。Ｙ^３－としては、ハロゲンイオンが好ましく、フッ素イオン、塩素イオン、臭素イオンがより好ましい。

However, in formula (iii), R ³¹ to R ³⁴ are the same as R ²¹ to R ²⁴ in formula (ii), and preferred embodiments are also the same. Y ^3- represents a monovalent anion. Y ^3- is preferably a halogen ion, more preferably a fluorine ion, a chloride ion, or a bromide ion.

The quaternary arsonium salts represented by the above formula (iii) include triphenylmethylarsonium fluoride, tetraphenylarsonium fluoride, triphenylmethylarsonium chloride, tetraphenylarsonium chloride, tetraphenylarsonium bromide, and the like. is mentioned.
As the quaternary arsonium salt, triphenylmethylarsonium chloride is preferred.

Sulfonium salts include compounds represented by the following formula (iv).

（ただし、式（iv）中、Ｒ^４１～Ｒ^４３及びＹ^４－は、式（iii）におけるＲ^３１～Ｒ^３４及びＹ^３－と同様であり、好ましい態様も同様である。）

(However, in formula (iv), R ⁴¹ to R ⁴³ and Y ^4- are the same as R ³¹ to R ³⁴ and Y ^3- in formula (iii), and preferred embodiments are also the same.)

The sulfonium salts represented by the above formula (iv) include di-n-butylmethylsulfonium iodide, tri-n-butylsulfonium tetrafluoroborate, dihexylmethylsulfonium iodide, dicyclohexylmethylsulfonium iodide, dodecylmethylethylsulfonium chloride, tris(diethylamino)sulfonium difluorotrimethylsilicate and the like.
As the sulfonium salt, dodecylmethylethylsulfonium chloride is preferred.

Crown ethers include 18-crown-6, dibenzo-18-crown-6, dicyclohexyl-18-crown-6 and the like.
Among the phase transfer catalysts described above, TBAC, TBAB, and TOMAC are preferred in terms of industrial availability, price, and ease of handling.

The amount of the phase transfer catalyst is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5.0 parts by mass, and further 0.1 to 2.0 parts by mass with respect to 100 parts by mass of 448occc. 0.1 to 1.5 parts by mass is particularly preferred. When the amount of the phase transfer catalyst is within the above range, a sufficient reaction rate is likely to be obtained. If it is outside the above range, it is difficult to obtain the effect of accelerating the reaction, which tends to be disadvantageous in terms of cost. When a phase transfer catalyst is used, it is preferable to mix the phase transfer catalyst to 448 occc in advance and supply the mixed liquid with 448 occc to the reactor. Moreover, the amount of the phase transfer catalyst is most preferably 0.1 to 1.0 parts by mass with respect to 100 parts by mass of 448 occc, because the selectivity and yield of 1437 dycc are high.

When a phase transfer catalyst is used, the materials of the reaction process, reactor, and reactor may be the same as when no phase transfer catalyst is used. Also, the reaction conditions such as the concentration of the base, the amount used, and the reaction temperature may be the same as when the phase transfer catalyst is not used.

In reaction (6), for example, 448 occc, an aqueous solution of a base, and if necessary, a water-soluble organic solvent and/or a phase transfer catalyst, and other compounds involved in the reaction are supplied to the reactor and stirred so that they become uniform. Then, it can be advanced by setting desired temperature and pressure conditions.

Reaction (6) may be carried out by compatibilizing the aqueous phase and the organic phase using a water-soluble organic solvent instead of the phase transfer catalyst in reaction (6). When using a water-soluble organic solvent, it is preferable to sufficiently stir the reaction system in order to make the compounds involved in the reaction in a uniform state. Examples of water-soluble organic solvents include dimethylsulfoxide, tetraglyme, and acetonitrile. Among them, dimethylsulfoxide and tetraglyme are preferable because they have a boiling point suitable for reaction (6). A phase transfer catalyst and a water-soluble organic solvent may be used in combination in reaction (6).

When the reaction solution after completion of the reaction is allowed to stand, it separates into an organic phase and an aqueous phase. The organic phase may contain by-products in addition to 448 occc of unreacted and 1437 dycc of the desired product. By-products include 1-chloro-3,3,4,4,5,5-hexafluoropentyne, 5-chloro-1,1,2,3,3,4,4-heptafluoropentene (HCFO -1437cycc, hereinafter also referred to as "1437cycc"). Further, when a composition containing 448occc and impurities is used as a raw material, 2,3,3,4,4,5,5-heptafluoro-1-( 2,2,3,3,4,4,5,5-octafluoropentoxy)pentene and the like may be included.

Other than the target product 1437dycc, it can be easily removed from the reaction product of reaction (6) by a known method such as separation by distillation. Unreacted 448occc can be reused as a starting material for reaction (6). At that time, the crude liquid after separating 1437 dycc from the reaction product may be used as it is, or the unreacted 448 occc may be purified from the crude liquid and used.

As described above, 1437cycc is mentioned as a by-product. 1437 cycc that is used can be reduced to 100 ppm or less. Therefore, the production method of the present embodiment is an excellent method capable of selectively producing the target compound 1437dycc.

According to the production method of the present embodiment, 1437 dycc, which is useful as a solvent and a working medium with a low global warming potential, is produced from 448 occc in an industrially feasible and economically advantageous manner with high selectivity and high yield. is obtained by

EXAMPLES The present invention will be specifically described below with reference to Examples. It should be noted that the present invention is not limited by these examples.

<Method for producing 448occc>
(First step; intermediate production step)
[Example 1-1]
A four-necked flask (reactor) equipped with a stirrer and a Dimroth condenser was immersed in an oil bath to form a reactor. After thionyl chloride was placed in the four-necked flask, a mixed solution of OFPO and DMF was dropped into the four-necked flask. The temperature of the oil bath was adjusted so that the reaction temperature was 50° C. during the dropwise addition of the mixed solution.

After the dropwise addition of the mixed solution is completed, stirring is continued until the generation of hydrogen chloride gas ceases, and an intermediate crude liquid containing 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite is obtained. got After that, the composition of the intermediate crude liquid was analyzed by 1H-NMR and 19F-NMR (manufactured by JEOL Ltd., JNM-ECP400). Table 1 summarizes the reaction conditions and the composition of the intermediate crude liquid.

In the table, the OFPO conversion rate (%) is the ratio of the molar amount of OFPO consumed in the first step to the molar amount of OFPO input in the first step ((molar amount of OFPO consumed) /(molar amount of OFPO charged)×100).

In the table, the intermediate selectivity (%) means the intermediates (2, 2, 3, 3, 4, 4, 5,5- octafluoropentyl chlorosulfite ) ((molar amount of intermediate produced)/(molar amount of OFPO consumed)×100).
Selectivities for other compounds are similarly calculated for each compound.
The term "active ingredient" refers to an intermediate and an intermediate-DMF adduct, and the "active ingredient selectivity" was calculated based on the total molar amount of the active ingredients.

Further, the intermediate yield (%) is the ratio of the molar amount of the intermediate produced in the first step to the molar amount of OFPO input in the first step ((molar amount of intermediate produced) / (molar amount of OFPO charged)×100). The reaction time is the elapsed time from the start of dropping of OFPO to the end of stirring, ie, the end of the reaction after generation of hydrogen chloride gas ceases.

[Examples 1-2 to 1-7]
The same reactor and procedure as in Example 1 were used, except that the reaction conditions were changed as shown in Table 1. Table 1 summarizes the reaction conditions, the composition of the intermediate crude liquid, and the analysis results.

(Second step; manufacturing process of 448occc)
[Example 2-1]
A four-necked flask equipped with a stirrer and a distillation column was charged with a crude intermediate liquid obtained by reacting OFPO and thionyl chloride at a reaction temperature of 30 to 70°C in the presence of DMF and DMF as a solvent, and the mixture was heated to 130°C. While heating, the distillation line (Dimroth condenser) was cooled to -20°C. Thus, 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite was thermally decomposed. Table 2 shows the composition of the crude intermediate liquid and the amount of the crude intermediate liquid used. The molar amount of the intermediate crude liquid was represented by the total molar amount of the compounds contained in the intermediate crude liquid.

Thereafter, the fraction was brought into contact with a 20% by mass potassium hydroxide aqueous solution for neutralization, and the organic phase portion was recovered from the fraction after neutralization and analyzed for its composition. Analysis was performed using gas chromatography (GC). DB-1301 (length 60 m×inner diameter 250 μm×thickness 1 μm, manufactured by Agilent Technologies) was used as the column. Table 2 shows the amount of 448occc obtained in the fractions.

Further, the composition of the still residue remaining in the four-necked flask was analyzed by 1H-NMR and 19F-NMR (manufactured by JEOL Ltd., JNM-ECP400). Furthermore, the amount of each compound recovered in the second step was calculated from the amount of 448 occc in the fraction and the composition of the still residue. Table 2 shows the results.

In Table 2, the intermediate conversion rate (%) is the intermediate consumed in the second step relative to the molar amount of the intermediate used in the second step (the molar amount of the intermediate in the intermediate crude liquid). is the ratio of molar amounts of intermediates ((molar amount of intermediate consumed)/(molar amount of intermediate charged)×100).

In Table 2, OFPO diadduct selectivity (%) means the ratio of the molar amount of OFPO diadduct produced in the second step to the molar amount of the intermediate consumed in the second step (( (molar amount of OFPO diadduct produced)/(molar amount of intermediate consumed)×100). Selectivities for other compounds are similarly calculated for each compound.

Further, the 448occc selectivity (%) is the ratio of the molar amount of 448occc produced in the second step to the molar amount of the intermediate consumed in the second step ((molar amount of 448occc produced) / (consumption is the molar amount of the intermediate obtained)×100).

[Example 2-2]
The second step was carried out using the same reactor and procedure as in Example 2-1, except that the reaction conditions were changed as shown in Table 2. Table 2 summarizes the reaction conditions, reaction results, and the like.

[Example 2-3]
A four-necked flask equipped with a stirrer and a distillation column was charged with a crude intermediate liquid obtained by reacting OFPO with thionyl chloride at a reaction temperature of 30 to 70°C in the presence of DMF and DMF as a solvent, and the mixture was heated to 110°C. While heating, the distillation line (Dimroth condenser) was cooled to -20°C. Thus, 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite was thermally decomposed. Table 2 shows the composition of the crude intermediate liquid and the amount of the crude intermediate liquid used. The molar amount of the intermediate crude liquid was represented by the total molar amount of the compounds contained in the intermediate crude liquid.

By 1H-NMR and 19F-NMR (manufactured by JEOL Ltd., JNM-ECP400), the composition of the still residue remaining in the four-necked flask was analyzed. Furthermore, the amount of each compound recovered in the second step was calculated from the composition of the still residue. Table 2 shows the results.

[Example 2-4]
The second step was carried out using the same reactor and procedure as in Example 2-1, except that the reaction conditions were changed as shown in Table 2. Table 2 summarizes the reaction conditions, reaction results, and the like.

[Example 2-5]
The second step was carried out in the same reactor and procedure as in Examples 2-3, except that the reaction conditions were changed as shown in Table 2. Table 2 summarizes the reaction conditions, reaction results, and the like.

After the reaction of OFPO with thionyl chloride in the presence of DMF to produce 2,2,3,3,3,4,4,5,5 -octafluoropentyl chlorosulfite, as shown in the examples above. , By thermally decomposing this 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite to obtain a reaction solution containing 448 occc, a complicated post-treatment process is unnecessary, It becomes possible to produce 448occc with high selectivity, and 448occc can be produced efficiently.

[Example 2-6]
The second step was carried out using the same reactor and procedure as in Example 2-1, except that the reaction conditions were changed as shown in Table 3. However, in Examples 2-6, no distillation line was used. By 1H-NMR and 19F-NMR (manufactured by JEOL Ltd., JNM-ECP400), the composition of the still residue remaining in the four-necked flask was analyzed. Furthermore, the amount of each compound recovered in the second step was calculated from the composition of the still residue. Table 3 summarizes the reaction conditions, reaction results, and the like.

[Examples 2-7 to 2-8]
Except that the reaction conditions were changed as shown in Table 3 (Table 2), the second step was performed in the same reactor and procedure as in Example 2-1, and the amount of each compound recovered in the second step was Calculated. Table 3 summarizes the reaction conditions, reaction results, and the like.

<Method for producing 1437dycc>
[Example 3-1]
100.7 g of 448 occc and 1.0 g of tetra-n-butylammonium bromide (TBAB) were placed in a 0.2-liter four-necked flask equipped with a stirrer and a Dimroth condenser, and the flask was cooled to 10°C. While maintaining the reaction temperature at 10° C., 153.9 g of a 34% by mass potassium hydroxide (KOH) aqueous solution was added dropwise over 30 minutes. After that, stirring was continued for 38 hours, and the organic layer was recovered. 448occc used above was prepared by reacting OFPO with thionyl chloride in the presence of DMF to produce 2,2,3,3,4,4,5,5-octafluoropentyl chlorosulfite , followed by It was prepared by pyrolysis of 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite .

Table 4 shows the results of analysis by gas chromatography after the collected organic layer was washed with water. In the table, the conversion rate of 448occc is the ratio (mol%) of the amount of 448occc consumed in the reaction to the total amount of 448occc supplied to the reactor. The selectivity of each compound is the ratio (mol %) of each component produced to the converted 448 occc, and was calculated from the GC analysis results. In addition, Table 4 also shows the actual amount charged and the reaction conditions. In Table 4, "TBAB/448occc" represents the charged amount (parts by mass) of TBAB with respect to 100 parts by mass of 448occc.

[Examples 3-2 to 3-4]
As shown in Table 4, a composition containing 1437 dycc was obtained by performing the same reaction as in Example 3-1, except that the actual charging amount and reaction temperature were changed. In Examples 3-3 and 3-4, the amount of solid precipitated was large, and the operation was terminated when the change in the conversion rate of 448 occc due to the reaction start time was no longer observed. Incidentally, the end point of the reaction was when the conversion rate of 448 occc reached 99% or more.

As can be seen from Table 4, according to Examples 3-1 to 3-4, the target 1437dycc could be produced with high selectivity and high yield while suppressing the amount of solid content produced. In addition, it was also found that the lower the reaction temperature, the smaller the amount of solid content produced, and the higher the selectivity and yield of 1437 dycc can be.

[Example 3-5]
As shown in Table 5, the reaction was carried out in the same manner as in Example 3-1, except that the actual charge amount and the charge amount of TBAB were changed, respectively, to obtain a composition containing 1437 dycc.
In Example 3-5, the operation was terminated when the conversion rate of 448 occc did not change depending on the reaction start time. Incidentally, the reaction end point was when the conversion rate of 448 occc reached 97% or more. For reference, Table 5 also shows Example 3-3 in which the reaction temperature was the same.

[Examples 3-6, 3-7]
As shown in Table 5, the reaction was carried out in the same manner as in Example 3-1, except that the actual charge amount and the KOH charge amount were changed, respectively, to obtain a composition containing 1437 dycc. The end point of the reaction was when the conversion rate of 448 occc reached 99% or more.

[Example 3-8]
As shown in Table 5, a composition containing 1437 dycc was obtained by performing the same reaction as in Example 3-1, except that the actual amount charged and the concentration of KOH were changed. The operation was terminated when the change in the conversion rate of 448 occc due to the reaction start time was no longer observed.

As can be seen from Examples 3-5 in Table 5, the larger the amount of TBAB charged, the shorter the reaction time. It was also found that 1437dycc can be produced without changing the selectivity and yield of 1437dycc by securing a sufficient reaction time even when the amount of TBAB charged is small.

As can be seen from Examples 3-6 to 3-7 in Table 5, by reducing the amount of KOH charged, the target 1437dycc can be produced with high selectivity and high yield while suppressing the amount of solid content produced. rice field. In addition, it can be seen that by reducing the amount of KOH charged, the volumetric efficiency is also improved, and as a result, the productivity is improved.

As can be seen from Examples 3-7 in Table 5, the higher the KOH concentration, the higher the conversion rate of 448 cccc and the faster the reaction rate.

As described above, the method for producing 1437dycc in the present embodiment can efficiently produce 1437dycc.

DESCRIPTION OF SYMBOLS 10, 20, 30... Reactor, 11, 21... Reactor, 12, 22a, 22b, 22c... Raw material supply means, 13, 23... Liquid supply means, 14, 24... Reactor, 15, 25... Liquid transfer means , 16, 26... alkali cleaning means, 17, 27... separation means, 31... reactor, 32... raw material tank, 33... cooler, 34... dehydration tower, 35... recovery tank.

Claims (12)

2,2,3,3,4,4,5,5-octa in the presence of at least one nitrogen-containing organic compound selected from the group consisting of N,N-dimethylformamide, dimethylacetamide, pyridine and tetramethylurea a first step of reacting fluoropentanol and thionyl chloride to produce 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite ;
By thermally decomposing the 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite , 5-chloro-1,1,2,2,3,3,4,4 - a second step to obtain octafluoropentane;
A method for producing 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane, characterized by having The method for producing 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane according to claim 1, wherein the reaction temperature is 0 to 70°C in the first step. In the first step, the molar ratio of thionyl chloride to 2,2,3,3,4,4,5,5-octafluoropentanol (thionyl chloride/2,2,3,3,4,4,5 ,5-octafluoropentanol) is 0.1 to 5. The method for producing 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane according to claim 1 or 2. . In the first step, one of 2,2,3,3,4,4,5,5-octafluoropentanol and thionyl chloride is used as a supply material, and the other is added per unit molar amount of the supply material 5-chloro-1,1,2,2,3,3,4,4-octa according to any one of claims 1 to 3, which is added at a rate of 0.0015 to 5 mol / mol · min as an amount A method for producing fluoropentane. 5. Any one of claims 1 to 4, wherein in the first step, the contact time between 2,2,3,3,4,4,5,5-octafluoropentanol and thionyl chloride is 1 to 8 hours. A method for producing 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane according to . In the first step, the mass ratio of the nitrogen-containing organic compound to 2,2,3,3,4,4,5,5-octafluoropentanol (nitrogen-containing organic compound/2,2,3,3,4 ,4,5,5-octafluoropentanol) is 0.001 to 1, 5-chloro-1,1,2,2,3,3,4 according to any one of claims 1 to 5. ,4-octafluoropentane production method. The 5-chloro-1,1,2,2,3,3,4, A method for producing 4-octafluoropentane. The 5-chloro-1,1,2,2,3,3,4,4-octafluoro according to any one of claims 1 to 7, wherein the thermal decomposition reaction is performed in a solvent in the second step. A method for producing pentane. 9. The method for producing 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane according to claim 8, wherein in the second step, the solvent is a nitrogen-containing organic compound. 10. The solvent of 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane according to claim 8 or 9, wherein in the second step, the solvent is N,N-dimethylformamide. Production method. In the second step, the mass ratio of the solvent to the 2,2,3,3,4,4,5,5 -octafluoropentyl chlorosulfite (solvent/2,2,3,3,4, 4,5,5- octafluoropentyl chlorosulfite ) is 0.01 to 1, 5-chloro-1,1,2,2,3,3 according to any one of claims 8 to 10 ,4,4-octafluoropentane production method. 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane is obtained by the production method according to any one of claims 1 to 11, and the obtained 5-chloro- 1-Chloro-2,3,3,4,4,5, 1-chloro-2,3,3,4,4,5, by dehydrofluorinating 1,1,2,2,3,3,4,4-octafluoropentane in an aqueous base solution. A process for producing 1-chloro-2,3,3,4,4,5,5-heptafluoropentene, characterized in that 5-heptafluoropentene is obtained.

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