Hydrochlorofluorocarbon manufacturing method

Abstract

Provided is a method for producing hydrochlorofluorocarbon with high yield and high purity while reducing the production amount of by-products.　The method for producing hydrochlorofluorocarbon comprises reacting a fluorinated alcohol with a chlorinating agent in the presence of a catalyst to substitute a hydroxyl group in the fluorinated alcohol by a chlorine atom, the method being characterized in that the catalyst is a phosphine oxide and at least one chlorinating agent selected from the group consisting of thionyl chloride, oxalyl chloride and phosgene is used as the chlorinating agent.

Description

[Technical Field]

[0001] The present invention relates to a method for producing hydrochlorofluorocarbons. [Background technology]

[0002] Hydrochlorofluorocarbons (hereinafter also referred to as HCFCs) are used as new cleaning agents, refrigerants, blowing agents, and aerosols, or as raw materials for synthesizing them. For example, HCFCs are sometimes used as raw materials for synthesizing hydrochlorofluoroolefins (hereinafter also referred to as HCFOs). Specifically, Patent Document 1, for example, describes that 3-chloro-1,1,2,2-tetrafluoropropane (HCFC-244ca, hereinafter also referred to as 244ca) is used as a raw material for synthesizing 1-chloro-2,3,3-trifluoropropene (HCFO-1233yd, hereinafter also referred to as 1233yd). Furthermore, Patent Document 2 describes that 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane (HCFC-448occc, hereinafter also referred to as 448occc) is used as a synthetic raw material for producing 1-chloro-2,3,3,4,4,5,5-heptafluoropentene (HCFO-1437dycc, hereinafter also referred to as 1437dycc). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2018 / 131394 [Patent Document 2] International Publication No. 2019 / 124220 Summary of the Invention [Problem to be solved by the invention]

[0004] HCFCs can be obtained by reacting a fluorine-containing alcohol with a chlorinating agent. However, in the HCFC production methods described in prior art documents, by-products such as a compound in which two molecules of a fluorine-containing alcohol are added to the chlorinating agent (hereinafter also referred to as a fluorine-containing alcohol diadduct) are produced in addition to the target HCFC. Therefore, a process for converting such by-products into HCFCs is required after chlorination. The present invention has been made to solve the above problems, and an object of the present invention is to provide a method for producing HCFC in high yield and high purity with a small amount of by-products produced. [Means for solving the problem]

[0005] As a result of extensive research into solving the above problems, the present inventors have found that the above problems can be solved by the following configuration. (1) A method for producing a hydrochlorofluorocarbon, comprising reacting a fluorine-containing alcohol with a chlorinating agent in the presence of a catalyst to substitute a hydroxyl group of the fluorine-containing alcohol with a chlorine atom, the catalyst is a phosphine oxide; A method for producing a hydrochlorofluorocarbon, characterized in that the chlorinating agent used is at least one chlorinating agent selected from the group consisting of thionyl chloride, oxalyl chloride and phosgene. (2) The method according to (1), wherein the fluorine-containing alcohol is a compound represented by the following formula (1): XR f -CH2OH (1) (wherein X represents a hydrogen atom or a fluorine atom, R f represents a fluoroalkylene group having one or more carbon atoms. (3) The method according to (1) or (2), wherein the fluorine-containing alcohol is 2,2,3,3-tetrafluoropropanol or 2,2,3,3,4,4,5,5-octafluoropentanol. (4) The method according to any one of (1) to (3), wherein the phosphine oxide is a compound represented by the following formula (2): [ka] (In the formula, R 1 ,R 2 ,R 3 each independently represents a monovalent hydrocarbon group which may have a substituent, or a monovalent nitrogen-containing heterocyclic group which may have a substituent (provided that a carbon atom constituting the ring is bonded to a phosphorus atom). (5) R 1 ~R 3 are both phenyl groups or R 1 and R 2 is a phenyl group and R 3 is a pyridyl group or R 1 ~R 3 are both 4-fluorophenyl groups, or R 1 ~R 3 are both 2-tolyl groups. (6) The method according to any one of (1) to (5), wherein the chlorinating agent is thionyl chloride or oxalyl chloride. (7) The method according to any one of (1) to (6), wherein the reaction does not involve any alcohol other than the fluorine-containing alcohol. (8) The production method according to any one of (1) to (7), wherein the content of the fluorine-containing alcohol diadduct contained in the reaction solution obtained by the reaction is 10 mass % or less based on the total amount of the reaction solution. (9) The method according to any one of (1) to (8), wherein the reaction temperature is 0 to 150°C. (10) The method according to any one of (1) to (9), wherein the reaction time is 2 to 8 hours. (11) The method according to any one of (1) to (10), wherein the fluorine-containing alcohol is reacted at a molar ratio of the chlorinating agent to the fluorine-containing alcohol (chlorinating agent / fluorine-containing alcohol) of 0.01 to 100. (12) The method according to any one of (1) to (11), wherein the reaction is carried out at a molar ratio of the phosphine oxide to the fluorine-containing alcohol (phosphine oxide / fluorine-containing alcohol) of 0.0001 to 10. (13) A method for producing a hydrochlorofluoroolefin, comprising subjecting a hydrochlorofluorocarbon obtained by the production method according to any one of (1) to (12) above to a dehydrofluorination reaction in the presence of a base and / or a catalyst. (14) The method according to (13), wherein the hydrochlorofluorocarbon is 3-chloro-1,1,2,2-tetrafluoropropane or 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane. (15) The production method according to (13) or (14), wherein the hydrochlorofluoroolefin is 1-chloro-2,3,3-trifluoropropene or 1-chloro-2,3,3,4,4,5,5-heptafluoropentene. [Effects of the Invention]

[0006] According to the present invention, a method for producing HCFC with high yield and high purity while producing a small amount of by-products can be provided. DETAILED DESCRIPTION OF THE INVENTION

[0007] The method for producing HCFCs of the present invention (hereinafter also simply referred to as "the production method of the present invention") is characterized by using a phosphine oxide as a catalyst and reacting a fluorine-containing alcohol with a specific chlorinating agent in the presence of the catalyst. The reaction between the fluorine-containing alcohol and the specific chlorinating agent substitutes hydroxyl groups of the fluorine-containing alcohol with chlorine atoms to produce HCFCs. In the production method of the present invention, the amount of by-products produced is small, and HCFC can be produced in high yield and with high purity. In the following, first, the components used in the production method of the present invention will be described in detail, and then the procedure of the production method will be described in detail.

[0008] (Fluorine-containing alcohol) In the production method of the present invention, a fluorine-containing alcohol is used as a raw material. The fluorine-containing alcohol raw material may be a mixture of two or more kinds of fluorine-containing alcohols. In other words, the production method of the present invention is industrially advantageous because it allows simultaneous production of two or more kinds of HCFCs.

[0009] The fluorine-containing alcohol used in the production method of the present invention is not particularly limited, but from the viewpoint of reactivity, it is preferably a primary alcohol, that is, a compound represented by the following formula (1). XR f -CH2OH (1) (wherein X represents a hydrogen atom or a fluorine atom, R f represents a fluoroalkylene group having one or more carbon atoms. R f The number of carbon atoms in R is preferably 1 to 7, more preferably 1 to 5, further preferably 1 to 4, and particularly preferably 2 to 4. f may contain a hydrogen atom, but is preferably a perfluoroalkylene group, and particularly preferably a linear perfluoroalkylene group.

[0010] Examples of fluorine-containing alcohols include 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoropropanol (hereinafter also referred to as TFPO), 2,2,3,3,3-pentafluoropropanol, 2,2,3,3,4,4,4-heptafluorobutanol, 2,2,3,4,4,4-hexafluorobutanol, 2,2,3,3,4,4,5,5-octafluoropentanol (hereinafter also referred to as OFPO), 3,3,4,4,5,5,6,6,6-nonafluorohexanol, and 4,4,5,5,6,6,7,7,7-nonafluoroheptanol. The fluorine-containing alcohol is preferably 2,2,2-trifluoroethanol, TFPO, 2,2,3,3,3-pentafluoropropanol, 2,2,3,3,4,4,4-heptafluorobutanol, 2,2,3,4,4,4-hexafluorobutanol, OFPO, or 3,3,4,4,5,5,6,6,6-nonafluorohexanol, more preferably TFPO, 2,2,3,3,3-pentafluoropropanol, 2,2,3,3,4,4,4-heptafluorobutanol, 2,2,3,4,4,4-hexafluorobutanol, or OFPO, and particularly preferably TFPO or OFPO.

[0011] When a fluorine-containing alcohol is used, it may be a mixture with other compounds. In other words, the raw material for the production method of the present invention may contain a fluorine-containing alcohol, and for example, a mixture of a fluorine-containing alcohol and other compounds may be used as the raw material.

[0012] Other compounds contained in the raw materials used in the production method of the present invention include impurities such as raw materials for producing fluorinated alcohols and by-products other than fluorinated alcohols produced during the production of fluorinated alcohols. When the raw materials contain the above impurities, the by-products produced from the impurities may be removed by known means such as distillation, extractive distillation, azeotropic distillation, membrane separation, two-phase separation, adsorption, etc. The impurities are preferably compounds that are inactive in the production method of the present invention.

[0013] The raw material preferably contains the fluorine-containing alcohol as a main component. The content of the fluorine-containing alcohol relative to the total mass of the raw material is preferably 50% by mass or more, more preferably 75% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more. The upper limit can be 100% by mass.

[0014] In addition, in order to increase the selectivity of HCFC in the reaction of a fluorine-containing alcohol with a specific chlorinating agent, it is preferable that no alcohol other than the fluorine-containing alcohol is contained. The amount of the alcohol other than the fluorine-containing alcohol 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, based on the total amount of the fluorine-containing alcohol.

[0015] (chlorinating agent) The chlorinating agent used in the production method of the present invention is at least one chlorinating agent selected from the group consisting of thionyl chloride, oxalyl chloride and phosgene, from the viewpoint of reactivity with the catalyst described below. As these chlorinating agents, a mixture of two or more thereof may be used. As the chlorinating agent, thionyl chloride and oxalyl chloride are preferred since HCFC can be produced more efficiently.

[0016] In the production method of the present invention, the molar ratio of the chlorinating agent to the fluorine-containing alcohol used (molar amount of chlorinating agent / molar amount of fluorine-containing alcohol) is preferably 0.01 to 100, more preferably 0.05 to 50, further preferably 0.1 to 10, particularly preferably 0.5 to 5, from the viewpoint of more efficient production of HCFC. When it is within the above range, the production of by-products is suppressed and the volumetric efficiency of the reactor is improved.

[0017] (catalyst) The phosphine oxide used as the catalyst in the production method of the present invention is preferably a phosphine oxide compound represented by the following formula (2).

[0018] [ka]

[0019] In equation (2), R 1 ,R 2 ,R 3each independently represents a monovalent hydrocarbon group which may have a substituent, or a monovalent nitrogen-containing heterocyclic group which may have a substituent (provided that a carbon atom constituting the ring is bonded to a phosphorus atom).

[0020] Examples of the monovalent hydrocarbon group include monovalent aliphatic hydrocarbon groups such as alkyl groups, alkenyl groups, and alkynyl groups, monovalent alicyclic hydrocarbon groups such as cycloalkyl groups and cycloalkenyl groups, and aryl groups such as phenyl groups. The number of carbon atoms in the monovalent hydrocarbon group, excluding substituents, is preferably 8 or less, and more preferably 6 or less. Examples of the substituent that the monovalent aliphatic hydrocarbon group may have include a monovalent alicyclic hydrocarbon group, an aryl group, a monovalent heterocyclic group, a halogen atom such as a fluorine atom, an alkoxy group, etc. Examples of the substituent that the monovalent alicyclic hydrocarbon group may have include a monovalent alicyclic hydrocarbon group, an aryl group, a monovalent heterocyclic group, a halogen atom such as a fluorine atom, an alkoxy group, etc. Examples of the substituent that the aryl group may have include a monovalent alicyclic hydrocarbon group, a monovalent heterocyclic group, a halogen atom such as a fluorine atom, an alkoxy group, etc. Examples of the monovalent nitrogen-containing heterocyclic group include heterocyclic groups having 1 or 2 nitrogen atoms, such as a pyridyl group and an imidazolyl group. Examples of the substituent that the monovalent nitrogen-containing heterocyclic group may have include a monovalent alicyclic hydrocarbon group, an aryl group, and a halogen atom such as a fluorine atom.

[0021] In the production method of the present invention, HCFC can be produced more efficiently, so R 1 ,R 2 ,R 3 are each independently preferably a phenyl group, a pyridyl group, a 4-fluorophenyl group, a 2-tolyl group, a methyl group, a butyl group, or a 3-methylcyclopentenyl group, more preferably a phenyl group, a pyridyl group, a 4-fluorophenyl group, or a 2-tolyl group, even more preferably a phenyl group, a pyridyl group, or a 4-fluorophenyl group, and particularly preferably a phenyl group.

[0022] Specifically, R1 ~R 3 are both phenyl groups or R 1 and R 2 is a phenyl group and R 3 is a pyridyl group or R 1 ~R 3 are both 4-fluorophenyl groups, or R 1 ~R 3 are preferably both 2-tolyl groups, and R 1 ~R 3 are both phenyl groups or R 1 and R 2 is a phenyl group and R 3 is a pyridyl group, or R 1 ~R 3 are more preferably 4-fluorophenyl groups, and R 1 ~R 3 are particularly preferably phenyl groups.

[0023] In the production method of the present invention, the molar ratio of the phosphine oxide used to the fluorine-containing alcohol used (molar amount of phosphine oxide / molar amount of fluorine-containing alcohol) is preferably 0.0001 to 10, more preferably 0.001 to 5, still more preferably 0.01 to 1, and particularly preferably 0.1 to 0.5, in order to obtain a sufficient reaction rate.

[0024] In the production method of the present invention, the phosphine oxide is preferably used by dissolving it in a reaction component or an inert solvent. From the viewpoint of reducing waste liquid, it is preferable to use it by dissolving it in a fluorine-containing alcohol or a chlorinating agent.

[0025] (Manufacturing method) In the production method of the present invention, a fluorine-containing alcohol is contacted with a chlorinating agent in the presence of phosphine oxide using a reactor.

[0026] The reactor is not particularly limited in shape and structure, as long as it can introduce and react the fluorine-containing alcohol and the chlorinating agent. Examples of such a reactor include a glass reactor, a stainless steel reactor, a glass-lined reactor, and a resin-lined reactor. The temperature control unit can be any unit that can adjust the reaction temperature between the fluorine-containing alcohol and the chlorinating agent. Examples of such a unit include an oil bath. The temperature control unit may be provided integrally with the reactor.

[0027] The production method of the present invention can be carried out by either a gas phase reaction or a liquid phase reaction, and is preferably carried out by a liquid phase reaction from the viewpoint of industrial implementation. Carrying out a liquid phase reaction means that a fluorine-containing alcohol and a chlorinating agent are reacted in the presence of phosphine oxide, each in a liquid state.

[0028] A specific procedure for the gas phase reaction is to supply raw materials, fluorine-containing alcohol and a chlorinating agent, heated to a gaseous state into a reactor, and bring the phosphine oxide filled in the reactor into contact with the gaseous fluorine-containing alcohol and chlorinating agent to obtain HCFC. A gas inert to the reaction (dilution gas) may be supplied to the reactor because it is effective in adjusting the flow rate, suppressing by-products, suppressing catalyst deactivation, etc. Specific examples of the dilution gas include nitrogen, carbon dioxide, helium, and argon.

[0029] A specific procedure for the liquid phase reaction includes a method of obtaining HCFC by dissolving phosphine oxide in a fluorine-containing alcohol or a chlorinating agent in advance, and contacting the liquid fluorine-containing alcohol with the liquid chlorinating agent by means of stirring, etc. It is preferable to dissolve phosphine oxide in a chlorinating agent, and contacting the liquid fluorine-containing alcohol with the liquid chlorinating agent by means of stirring, etc.

[0030] The liquid fluorine-containing alcohol, the catalyst, and the chlorinating agent may be added to the reactor simultaneously, and the reactor may be heated after the addition, or the reactor containing the catalyst and the chlorinating agent may be heated and then the fluorine-containing alcohol may be added. In order to control the sulfur dioxide gas and hydrogen chloride gas generated at the start of the reaction, it is preferable to control the addition rate. Of these, the latter liquid phase reaction is preferred from the viewpoints of reaction temperature, reaction time, reaction yield, and HCFC selectivity. Furthermore, when the production method of the present invention is carried out by a liquid phase reaction, it is preferred from the viewpoint that a reactor of a smaller size can be used compared to a gas phase reaction.

[0031] The reaction temperature (temperature inside the reactor) in the production method of the present invention is preferably 0 to 150°C, more preferably 10 to 125°C, and even more preferably 20 to 100°C, from the viewpoint of more efficient production of HCFC. If the reaction temperature does not reach the above range, the reaction rate and reaction yield may decrease, and an excessive amount of unreacted fluorine-containing alcohol may remain, which tends to reduce the conversion rate of the fluorine-containing alcohol. On the other hand, if the reaction temperature exceeds the above range, an excessive amount of fluorine-containing alcohol diadduct is produced, which tends to reduce the selectivity for HCFC. The temperature inside the reactor can be controlled by adjusting the temperature and pressure of the raw materials supplied to the reactor. If necessary, the inside of the reactor can be supplementarily heated by an electric heater, a microwave generator, or the like.

[0032] The production method of the present invention may be carried out batchwise or continuously. When carried out batchwise, a predetermined amount of one of the fluorine-containing alcohol and the chlorinating agent is placed in a reactor as a feed material, and the other is gradually added to the feed material in the reactor. For example, a predetermined amount of the chlorinating agent is placed in a reactor as a feed material, and the fluorine-containing alcohol is gradually added to the chlorinating agent, or a predetermined amount of the fluorine-containing alcohol is placed in a reactor as a feed material, and the chlorinating agent is gradually added to the fluorine-containing alcohol. In this case, it is preferable that the phosphine oxide is mixed in advance with the fluorine-containing alcohol or the chlorinating agent. The entire predetermined amount of phosphine oxide may be mixed with either the fluorine-containing alcohol or the chlorinating agent. Alternatively, a predetermined amount of phosphine oxide may be divided and mixed with the fluorine-containing alcohol and the chlorinating agent.

[0033] When the process is carried out continuously, the fluorine-containing alcohol, chlorinating agent, and phosphine oxide are continuously fed into a reactor at a predetermined molar ratio at a predetermined feed rate, and are contacted in the reactor for a predetermined time. In this case, it is preferable from the viewpoint of operational efficiency that the phosphine oxide is mixed with the fluorine-containing alcohol or the chlorinating agent in advance and then fed into the reactor. When the production method of the present invention is carried out continuously, the feed rates of the fluorine-containing alcohol, chlorinating agent, and phosphine oxide to the reactor are adjusted depending on the feed flow rates of each compound and the sulfur dioxide gas or hydrogen chloride gas generated during the reaction.

[0034] The reaction time in the production method of the present invention varies depending on the amounts of phosphine oxide, fluorine-containing alcohol, and chlorinating agent, but is, for example, 2 to 8 hours. The reaction time in the production method of the present invention is represented by the contact time between the fluorine-containing alcohol and the chlorinating agent. For example, as described above, when the reaction is carried out batchwise by placing a predetermined amount of either the fluorine-containing alcohol or the chlorinating agent in a reactor as a feed material and gradually adding the other to the feed material in the reactor, the reaction time is the time from the start of feeding either the fluorine-containing alcohol or the chlorinating agent as a feed material to the end of the reaction when the generation of hydrogen chloride gas subsides. When the production method of the present invention is carried out continuously, the reaction time is the residence time of the fluorine-containing alcohol and the chlorinating agent in the reactor.

[0035] When the production method of the present invention is carried out by a liquid phase reaction, it is preferable to contact the reaction mixture containing HCFC with an aqueous alkali solution in order to neutralize the hydrogen chloride and sulfur dioxide in the reaction mixture containing HCFC. Examples of the aqueous alkali solution used in this case include an aqueous sodium hydroxide solution and an aqueous potassium hydroxide solution. After contact with the aqueous alkali solution, the reaction mixture containing HCFC is allowed to stand and separated into an organic phase and an aqueous phase. Since the HCFC is contained in the organic phase, the HCFC can be obtained by separating and recovering the organic phase.

[0036] The obtained organic layer liquid may contain, in addition to HCFC, for example, phosphine oxide, unreacted raw materials such as a fluorine-containing alcohol and a chlorinating agent, and may also contain, as by-products, fluorine-containing alcohol diadducts and by-products derived from fluorine-containing alcohols other than the fluorine-containing alcohol diadducts. However, in the production method of the present invention, fluorine-containing alcohol diadducts are usually not contained. The liquid of the organic layer containing the unreacted raw materials and by-products is preferably separated and purified by ordinary distillation or the like, if necessary, to obtain HCFC with reduced amounts of the unreacted raw materials and by-products.

[0037] The reaction liquid obtained after purification, if necessary, preferably contains HCFC as a major component. The content of HCFC relative to the total mass of the reaction liquid is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass. The upper limit can be 100% by mass.

[0038] The HCFC obtained by the production method of the present invention may be subjected to a dehydrofluorination reaction to produce an HCFO. Specifically, the HCFC obtained by the production method of the present invention is subjected to a dehydrofluorination reaction in the presence of a base and / or a catalyst to produce an HCFO. When the raw material for producing HCFO contains a fluorinated alcohol diadduct, the fluorinated alcohol diadduct decomposes into a fluorinated alcohol in the reactor and reacts with the HCFO product, which may reduce the selectivity for HCFO. The content of fluorine-containing alcohol diadducts contained in the reaction liquid containing HCFC obtained by the reaction of a fluorine-containing alcohol with a chlorinating agent is preferably 10% by mass or less, more preferably 5% by mass or less, and particularly preferably 1% by mass or less, based on the total amount of the reaction liquid containing HCFC. Most preferably, the reaction liquid does not contain fluorine-containing alcohol diadducts. The production method of the present invention is preferably applied to the production of HCFO, since it can suppress the production of by-products.

[0039] In this specification, unless otherwise specified, compound names or abbreviations refer to at least one selected from the Z isomer and the E isomer, and more specifically, refer to the Z isomer or the E isomer, or a mixture of the Z isomer and the E isomer in any ratio. When a compound name or abbreviation is followed by (E) or (Z), it refers to the (E) isomer or (Z) isomer of the respective compound. For example, 1233yd(Z) refers to the Z isomer, and 1233yd(E) refers to the E isomer.

[0040] In the production method of the present invention, when the fluorine-containing alcohol is TFPO, 244ca is obtained. The reaction mixture contains 244ca as a major component. Components other than 244ca can be removed to the desired extent by known means such as distillation, extractive distillation, azeotropic distillation, membrane separation, two-phase separation, and adsorption.

[0041] The resulting 244ca may be subjected to a dehydrofluorination reaction to produce 1233yd. The procedure for the dehydrofluorination reaction may be a known method such as that described in WO 2016 / 136744.

[0042] The dehydrofluorination reaction of 244ca may be either a liquid-phase reaction or a gas-phase reaction. The liquid-phase reaction refers to the dehydrofluorination of 244ca in a liquid state or dissolved in a liquid. The gas-phase reaction refers to the dehydrofluorination of 244ca in a gaseous state.

[0043] In the production method of the present invention, when the fluorine-containing alcohol is OFPO, 448 occc is obtained. The reaction mixture contains 448 occc as the main component. Components other than 448 occc can be removed to the desired extent by known means such as distillation, extractive distillation, azeotropic distillation, membrane separation, two-phase separation, and adsorption.

[0044] The resulting 448occc may be dehydrofluorinated to produce 1437dycc. It is particularly preferable to produce 1437dycc(Z). The procedure for the dehydrofluorination reaction may be a known method such as that described in Zhurnal Organicheskoi Khimii (Russia), 1988, Vol. 24, No. 8, pp. 1626-1633.

[0045] The dehydrofluorination reaction of 448occc may be either a liquid-phase reaction or a gas-phase reaction. The liquid-phase reaction refers to the dehydrofluorination of 448occc in a liquid state or dissolved in a liquid. The gas-phase reaction refers to the dehydrofluorination of 448occc in a gaseous state. [Example]

[0046] The present invention will be explained in more detail below with reference to examples, but is not limited to these examples. Examples 1 to 3, 6, 8 and 9 are examples of the present invention, and Examples 4, 5 and 7 are comparative examples.

[0047] (Example 1) A four-neck flask (reactor) equipped with a stirrer, a glass distillation column (measured plate number: 5) packed with Raschig rings, and a Dimroth condenser was immersed in an oil bath to form a reaction apparatus. 1 ~R 3 All of these are phenyl groups.) (hereinafter also referred to as Ph3PO) (5.27 g), thionyl chloride (49.5 g), and TFPO (50.0 g) were added, and the temperature of the oil bath was adjusted so that the reaction temperature would be 80°C. TFPO was converted to 244ca and simultaneously distilled to obtain a distillate containing 244ca. The reflux time / distillation time ratio (seconds / seconds) was set to 10 / 1 using a reflux timer. The distillate was then contacted with a 10% by weight aqueous potassium hydroxide solution to neutralize sulfur dioxide gas and other contaminants in the distillate. The organic phase was recovered from the neutralized distillate and its composition was analyzed. Analysis was performed using gas chromatography (GC). A DB-1301 column (60 m length x 250 μm inner diameter x 1 μm thickness, manufactured by Agilent Technologies, Inc.) was used. Also, 1 H-NMR and 19 The reaction solution remaining in the reactor was analyzed by C-NMR (JNM-EC P400, manufactured by JEOL Ltd.). The results are shown in Table 1.

[0048] (Example 2) The reaction apparatus was a four-neck flask (reactor) equipped with a stirrer, a glass distillation column (measured 5 plates) packed with Raschig rings, and a Dimroth condenser, immersed in an oil bath. The reaction was carried out in the same manner as in Example 1, except that OFPO was used as the raw material instead of TFPO. The results are shown in Table 1.

[0049] (Example 3) The reaction apparatus was a four-neck flask (reactor) equipped with a stirrer, a glass distillation column (measured 5 plates) packed with Raschig rings, and a Dimroth condenser, immersed in an oil bath. The reaction was carried out in the same manner as in Example 1, except that oxalyl chloride was used as the chlorinating agent instead of thionyl chloride. The results are shown in Table 1.

[0050] (Example 4) (First step) A four-neck flask (reactor) equipped with a stirrer, a glass distillation column (measured number of plates: 5) packed with Raschig rings, and a Dimroth condenser was immersed in an oil bath to form a reaction apparatus. After thionyl chloride was added to the four-neck flask, a mixed solution consisting of TFPO and N,N-dimethylformamide (hereinafter also referred to as DMF) was added dropwise to the four-neck flask. During the dropwise addition of the mixed solution, the temperature of the oil bath and the dropping rate of the mixed solution were adjusted so that the reaction temperature (temperature of the liquid phase in the four-neck flask) was 0°C. After the dropwise addition of the mixed solution was completed, stirring was continued until the evolution of hydrogen chloride gas subsided, and the reaction product mixture containing 2,2,3,3-tetrafluoropropanesulfonic acid chloride was recovered.

[0051] (Second step) In the same reactor as in the first step, 40 g of DMF was placed in a four-neck flask, and the four-neck flask was heated to 120°C while the Dimroth condenser was cooled to -20°C. The reaction product mixture containing 2,2,3,3-tetrafluoropropanesulfonic acid chloride obtained in the first step was fed to the flask at a rate of 75 g / hr using a liquid pump. The reactor (four-neck flask) was then cooled to room temperature to terminate the reaction. This resulted in the pyrolysis of 2,2,3,3-tetrafluoropropanesulfonic acid chloride and simultaneous distillation, yielding a distillate containing 244 ca. The reflux time / distillation time ratio (seconds / seconds) was set to 5 / 1 using a reflux timer.

[0052] The sulfur dioxide gas remaining in the distillate was then neutralized with a 20% by mass aqueous solution of potassium hydroxide. The organic phase was recovered from the neutralized distillate and its composition was analyzed. The results are shown in Table 1.

[0053] (Example 5) (First step) A four-neck flask (reactor) equipped with a stirrer, a glass distillation column (measured five plates) packed with Raschig rings, and a Dimroth condenser was immersed in an oil bath to form a reaction apparatus. After adding thionyl chloride to the four-neck flask, a mixed solution consisting of OFPO and DMF was added dropwise to the four-neck flask. During the dropwise addition of the mixed solution, the temperature of the oil bath and the dropping rate of the mixed solution were adjusted so that the reaction temperature (temperature of the liquid phase in the four-neck flask) was 50°C. After the dropwise addition of the mixed solution was completed, stirring was continued until the evolution of hydrogen chloride gas subsided, and the reaction product mixture containing 2,2,3,3,4,4,5,5-octafluoropentanesulfonic acid chloride was recovered.

[0054] (Second step) In the same reactor as in the first step, 40 g of DMF was placed in a four-neck flask, and the four-neck flask was heated to 130 °C while the Dimroth condenser was cooled to -20 °C. The reaction product mixture containing 2,2,3,3,4,4,5,5-octafluoropentanesulfonic acid chloride obtained in the first step was fed to the flask at a rate of 75 g / hr using a liquid pump. The reactor (four-neck flask) was then cooled to room temperature, and the reaction was terminated. This resulted in the pyrolysis of 2,2,3,3-tetrafluoropropanesulfonic acid chloride and simultaneous distillation, yielding a distillate containing 448 occc. The reflux time / distillation time ratio (seconds / seconds) was set to 5 / 1 using a reflux timer.

[0055] The sulfur dioxide gas remaining in the distillate was then neutralized with a 20% by mass aqueous solution of potassium hydroxide. The organic phase was recovered from the neutralized distillate and its composition was analyzed. The results are shown in Table 1.

[0056] In Tables 1 and 2, the conversion rate represents the ratio (%) of the molar amount consumed in the reaction to the charged amount (molar amount), and the selectivity represents the molar amount consumed in producing each compound to the molar amount of the consumed raw material. The amount of chlorinating agent (mol / mol) represents the molar ratio of the chlorinating agent to the fluorine-containing alcohol. The amount of catalyst (mol / mol) represents the molar ratio of the catalyst to the fluorine-containing alcohol.

[0057] [Table 1]

[0058] (Example 6) A four-neck flask (reactor) equipped with a stirrer, a glass distillation column (measured number of plates: 5) packed with Raschig rings, and a Dimroth condenser was immersed in an oil bath to form a reaction apparatus. The reaction was carried out in the same manner as in Example 1, except that a mixture of TFPO and OFPO was used as the raw material instead of TFPO. The results are shown in Table 2.

[0059] (Example 7) A four-neck flask (reactor) equipped with a stirrer, a glass distillation column (measured plate number: 5) packed with Raschig rings, and a Dimroth condenser was immersed in an oil bath to form a reaction apparatus. The reaction was carried out in the same manner as in Example 4, except that a mixture of TFPO and OFPO was used as the raw material instead of TFPO. The results are shown in Table 2. The terms in Table 2 have the same meanings as in Table 1.

[0060] [Table 2]

[0061] (Example 8) The catalyst was 2-diphenylphosphorylpyridine (R 1 and R 2 is a phenyl group and R 3 The reaction was carried out in the same manner as in Example 1 except that the reaction was carried out using a pyridyl group. The results are shown in Table 3.

[0062] (Example 9) The catalyst was tris(4-fluorophenyl)phosphine oxide (R in (2) above) instead of PhPO. 1 ~R 3 The results of the reaction carried out in the same manner as in Example 1 except that the reaction was carried out using 4-fluorophenyl groups are shown in Table 3. The terms in Table 3 have the same meanings as in Table 1.

[0063] [Table 3] [Industrial Applicability]

[0064] According to the production method of the present invention, HCFC can be produced in high yield and high purity by reacting a fluorine-containing alcohol with a chlorinating agent in the presence of phosphine oxide without using any special operation or reaction equipment, making it possible to apply the method to mass production on an industrial scale.

[0065] The entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2020-150467, filed on September 8, 2020, are hereby incorporated by reference as the disclosure of the specification of the present invention.

Claims

1. A method for producing a hydrochlorofluorocarbon, comprising reacting a fluorine-containing alcohol with a chlorinating agent in the presence of a catalyst to substitute a hydroxyl group of the fluorine-containing alcohol with a chlorine atom, the catalyst is a phosphine oxide; A method for producing a hydrochlorofluorocarbon, characterized in that the chlorinating agent used is at least one chlorinating agent selected from the group consisting of thionyl chloride, oxalyl chloride and phosgene.

2. The method according to claim 1, wherein the fluorine-containing alcohol is a compound represented by the following formula (1): X-R ｆ -CH ２ OH (1) (wherein X represents a hydrogen atom or a fluorine atom, R ｆ represents a fluoroalkylene group having one or more carbon atoms.

3. 3. The method according to claim 1, wherein the fluorine-containing alcohol is 2,2,3,3-tetrafluoropropanol or 2,2,3,3,4,4,5,5-octafluoropentanol.

4. The method according to any one of claims 1 to 3, wherein the phosphine oxide is a compound represented by the following formula (2): 【Chemical 1】 (In the formula, R １ , R ２ , R ３ each independently represents a monovalent hydrocarbon group which may have a substituent, or a monovalent nitrogen-containing heterocyclic group which may have a substituent (provided that a carbon atom constituting the ring is bonded to a phosphorus atom).

5. R １ ~R ３ are all phenyl groups, or R １ and R ２ is a phenyl group and R ３ is a pyridyl group, or R １ ~R ３ are both 4-fluorophenyl groups, or R １ ~R ３ and each of the formulas is a 2-tolyl group.

6. The process according to any one of claims 1 to 5, wherein the chlorinating agent is thionyl chloride or oxalyl chloride.

7. The method according to any one of claims 1 to 6, wherein the reaction does not involve any alcohol other than the fluorine-containing alcohol.

8. The production method according to any one of claims 1 to 7, wherein the content of the fluorine-containing alcohol diadduct contained in the reaction solution obtained by the reaction is 10 mass% or less with respect to the total amount of the reaction solution.

9. The method according to any one of claims 1 to 8, wherein the reaction temperature is 0 to 150°C.

10. The method according to any one of claims 1 to 9, wherein the reaction time is 2 to 8 hours.

11. The method according to any one of claims 1 to 10, wherein the reaction is carried out at a molar ratio of the chlorinating agent to the fluorine-containing alcohol (chlorinating agent / fluorine-containing alcohol) of 0.01 to 100.

12. The method according to any one of claims 1 to 11, wherein the reaction is carried out at a molar ratio of the phosphine oxide to the fluorine-containing alcohol (phosphine oxide / fluorine-containing alcohol) of 0.0001 to 10.

13. A method for producing hydrochlorofluoroolefins, comprising reacting a fluorine-containing alcohol with a chlorinating agent in the presence of a catalyst to substitute a hydroxyl group of the fluorine-containing alcohol with a chlorine atom to produce a hydrochlorofluorocarbon, and then dehydrofluorinating the hydrochlorofluorocarbon in the presence of a base and / or a catalyst, the catalyst is a phosphine oxide; A method for producing a hydrochlorofluoroolefin, wherein the chlorinating agent used is at least one chlorinating agent selected from the group consisting of thionyl chloride, oxalyl chloride and phosgene.

14. The method according to claim 13, wherein the hydrochlorofluorocarbon is 3-chloro-1,1,2,2-tetrafluoropropane or 5-chloro-1,1,2,2,3,3,4,4-octafluoropentane.

15. The method according to claim 13 or 14, wherein the hydrochlorofluoroolefin is 1-chloro-2,3,3-trifluoropropene or 1-chloro-2,3,3,4,4,5,5-heptafluoropentene.

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