JP7348535B2 - Alkene production method - Google Patents

Description

The present disclosure relates to a method for producing alkenes.

US Pat. No. 5,001,001 discloses a method for preparing trifluoroethylene, which comprises contacting chlorotrifluoroethylene with hydrogen in the presence of a catalyst consisting of palladium or platinum supported on activated carbon. .

Special publication 2013-534529

The present disclosure aims to produce hydrogenated alkenes by hydrogen substitution.

The present disclosure includes the following configurations.

Item 1.
General formula (1):

(In the formula, R ¹ , R ² , and R ³ are the same or different and represent fluorine or a perfluoroalkyl group.)
A method for producing an alkene represented by
General formula (2):

(In the formula, X is a halogen atom, and R ¹ , R ² , and R ³ are the same or different and represent fluorine or a perfluoroalkyl group. In the formula, when X is a chlorine atom, Any one or more of R ¹ , R ² , and R ³ represents a perfluoroalkyl group.)
A manufacturing method comprising the step of hydrogenating an alkene represented by the following in the presence of an activated carbon catalyst supporting a noble metal or rare metal.

Item 2.
2. The manufacturing method according to item 1, wherein the hydrogenation reaction step is performed in a gas phase.

Item 3.
The noble metal or rare metal is at least one noble metal or rare metal selected from the group consisting of palladium (Pd), platinum (Pt), rhodium (Rh), ruthenium (Ru), and manganese (Mn). The manufacturing method according to item 1 or 2 above.

Item 4.
CF ₃ -CF=CH-CF ₃ ;
CF ₃ -CFH-CFH-CF ₃ ; and
A composition containing CF ₃ -CFH-CFH-CF ₂ H;

Item 5.
5. The composition according to item 4, which is used as an etching gas, a refrigerant, a heat transfer medium, a deposit gas, a building block for organic synthesis, or a cleaning gas.

According to the present disclosure, hydrogenated alkenes can be efficiently produced by hydrogen substitution.

In this specification, "contain" is a concept that includes all of "comprise," "consist essentially of," and "consist of." Furthermore, in this specification, when a numerical range is expressed as "A to B", it means greater than or equal to A and less than or equal to B.

As a result of extensive research, the inventors of the present invention were able to efficiently proceed with the hydrogenation reaction by carrying out the hydrogenation reaction of alkenes, which are raw material compounds, in the presence of a palladium-supported activated carbon catalyst. It was discovered that hydrogenated alkenes can be produced with high conversion (yield) and high selectivity.

The present disclosure has been completed as a result of further research based on this knowledge.

The present disclosure includes the following embodiments.

General formula (1) of the present disclosure:

(In the formula, R ¹ , R ² , and R ³ are the same or different and represent fluorine or a perfluoroalkyl group.)
The method for producing an alkene represented by
General formula (2):

(In the formula, X is a halogen atom, and R ¹ , R ² , and R ³ are the same or different and represent fluorine or a perfluoroalkyl group. In the formula, when X is a chlorine atom, Any one or more of R ¹ , R ² , and R ³ represents a perfluoroalkyl group.)
The method includes a step of hydrogenating an alkene represented by the following in the presence of an activated carbon catalyst supporting a noble metal or rare metal.

In the manufacturing method of the present disclosure, preferably, the hydrogenation reaction step is performed in a gas phase.

In the manufacturing method of the present disclosure, preferably, the noble metal or rare metal is at least selected from the group consisting of palladium (Pd), platinum (Pt), rhodium (Rh), ruthenium (Ru), and manganese (Mn). It is a kind of precious metal or rare metal.

The composition of the present disclosure comprises:
CF ₃ -CF=CH-CF ₃ ;
CF ₃ -CFH-CFH-CF ₃ ; and
Contains CF ₃ -CFH-CFH-CF ₂ H;

The compositions of the present disclosure are preferably used as etching gases, coolants, heat transfer media, deposit gases, building blocks for organic synthesis, or cleaning gases.

In the present disclosure, by satisfying the above requirements, the hydrogenation reaction proceeds efficiently and hydrogenated alkenes can be produced with high conversion rate (yield) and high selectivity.

In the present disclosure, "conversion rate" refers to the molar amount of the raw material compound (alkene containing a halogen atom) supplied to the reactor, as compared to the molar amount of the raw material compound (alkene containing a halogen atom) other than the raw material compound (hydrogenated It means the percentage (mol%) of the total molar amount of alkenes, etc.).

In this disclosure, "selectivity" refers to the target compound (hydrogenated alkenes, etc.) contained in the outflow gas relative to the total molar amount of compounds other than the raw material compounds (hydrogenated alkenes, etc.) in the outflow gas from the reactor outlet. ) means the percentage of the total molar amount (mol%).

The method for producing an alkene of the present disclosure can efficiently hydrogenate an alkene containing a halogen atom as a raw material compound, and can produce a hydrogenated alkene with a high conversion rate (yield) and high selectivity. There are many things that can be manufactured with.

(1) Raw material compound The raw material compound of the present disclosure has the general formula (2):

(In the formula, X is a halogen atom, and R ¹ , R ² , and R ³ are the same or different and represent fluorine or a perfluoroalkyl group. In the formula, when X is a chlorine atom, Any one or more of R ¹ , R ² , and R ³ represents a perfluoroalkyl group.)
It is an alkene represented by

In the alkene formula (2), X is a halogen atom, and R ¹ , R ² and R ³ are the same or different and represent fluorine or a perfluoroalkyl group.

In the alkene formula (2), when X is a chlorine atom, any one or more of R ¹ , R ² and R ³ represents a perfluoroalkyl group.

The halogen atom is preferably a fluorine atom, a bromine atom, an iodine atom, and a chlorine atom.

A perfluoroalkyl group is an alkyl group in which all hydrogen atoms are replaced with fluorine atoms. The perfluoroalkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, even more preferably 1 to 6 carbon atoms, particularly preferably 1 to 4 carbon atoms, and most preferably carbon atoms. It is a perfluoroalkyl group of number 1 to 3.

The perfluoroalkyl group is preferably a linear or branched perfluoroalkyl group. The perfluoroalkyl group is preferably a trifluoromethyl group (CF ₃ -) and a pentafluoroethyl group (C ₂ F ₅ -).

The alkene represented by the general formula (2) as a raw material compound undergoes a hydrogenation reaction efficiently in the presence of an activated carbon catalyst supporting a noble metal or rare metal, and the hydrogenated alkene can be converted to a high conversion rate and yield. The number of carbon atoms is preferably 2 to 8, more preferably 2 to 4, and still more preferably 4, since it can be produced with high yield and/or high selectivity.

In the alkene represented by the general formula (2) of the raw material compound, R ¹ , R ² , and R ³ are the same or different and represent fluorine or a perfluoroalkyl group.

The alkene represented by the general formula (2) of the raw material compound is preferably perfluoro-2-butene (F ₃ C-CF=CF-CF ₃ ), perfluoro-1-butene (CF ₃ -CF ₂ - CF=CF ₂ ) etc.

The alkene represented by the general formula (2) as a raw material compound can be used alone or in combination of two or more. Commercially available alkenes may also be used.

(2) Hydrogenation reaction In the hydrogenation reaction step of the present disclosure, an alkene represented by general formula (2) is hydrogenated using palladium-supported activated carbon as a catalyst.

The step of hydrogenation is preferably performed because the alkene represented by the general formula (2), which is a raw material compound, can be produced with a high conversion rate, high yield, and/or high selectivity. , carbon number is 2 to 8, more preferably 2 to 4, still more preferably 4.

In the hydrogenation step, the alkene represented by the general formula (2) as a raw material compound is efficiently hydrogenated in the presence of a palladium-supported activated carbon catalyst, and the hydrogenated alkene is Preferably, R ¹ , R ² , and R ³ are the same or different and represent fluorine or a perfluoroalkyl group, since they can be produced with high conversion, yield, and/or high selectivity.

The alkene represented by the general formula (2) of the raw material compound is preferably perfluoro-2-butene (CF ₃ -CF=CF-CF _{3 ), and the alkene represented by the general formula (1) of the target compound to be hydrogenated is preferably perfluoro-2-butene (CF 3 -CF=CF-CF 3} ). The alkene represented by is preferably 1,1,1,2,4,4,4-heptafluoro-2-butene (CF ₃ -CF=CH-CF ₃ ) ((Z/E)-1327myz) ).

Activated carbon catalyst supporting precious or rare metals
(Precious metal or rare metal catalyst supported on activated carbon)
In the hydrogenation reaction step of the present disclosure, an alkene represented by the general formula (2), which is a raw material compound, is hydrogenated using an activated carbon catalyst supporting a noble metal or a rare metal as a catalyst to form a target compound. to produce an alkene represented by the general formula (1), preferably 1,1,1,2,4,4,4-heptafluoro-2-butene, which is hydrogenated.

The hydrogenation reaction step is preferably carried out in a gas phase.

As a hydrogenation catalyst, the noble metal or rare metal is preferably at least one selected from the group consisting of palladium (Pd), platinum (Pt), rhodium (Rh), ruthenium (Ru), and manganese (Mn). It is a precious or rare metal.

As the hydrogenation catalyst, it is more preferable to use a palladium-supported activated carbon catalyst in which the noble metal or rare metal is palladium (Pd) and the carrier is activated carbon, so that a high metal surface area can be obtained and the hydrogenation reaction rate can be increased. You can get the effect of being fast.

The particle size of the activated carbon carrier is preferably about 0.1 mm to 100 mm.

The amount of palladium supported relative to the total mass of the catalyst used in the hydrogenation reaction step is preferably about 0.01% by mass to 20% by mass, more preferably about 0.1% by mass to 10% by mass.

A wide variety of known preparation methods can be used to prepare the catalyst. For example, a catalyst in which palladium metal is supported on an activated carbon carrier is prepared by immersing the activated carbon carrier in a solution containing palladium metal, impregnating the carrier with this solution, and then neutralizing and It can be obtained by a method such as firing. In this case, the amount of noble metal or rare metal supported on the carrier is adjusted depending on the concentration of the solution, the impregnation time, etc.

Amount of hydrogen used (H ₂ /alkene molar ratio)
In the hydrogenation reaction step of the present disclosure, the alkene to be hydrogenated can be produced with high conversion rate, yield, and/or high selectivity, so the amount of hydrogen used is limited to 1 mole of alkene. , preferably 0.1 mol to 10 mol (H ₂ /alkene molar ratio: 0.1 to 10), more preferably 1 mol to 5 mol (H ₂ /alkene molar ratio: 1 to 5), even more preferably, The amount is 1 mol to 3 mol (H ₂ /alkene molar ratio: 1 to 3), particularly preferably 1.1 mol (H ₂ /alkene molar ratio: 1.1).

Reaction temperature of hydrogenation reaction The hydrogenation reaction step of the present disclosure uses a palladium-supported activated carbon catalyst, and the lower limit of the reaction temperature is set so that the hydrogenation reaction can proceed more efficiently from the raw material compound and the conversion rate can be increased. From the viewpoint of further improving the selectivity of the target compound, the temperature is preferably 100°C or higher, more preferably 150°C or higher, and even more preferably 200°C or higher.

In the hydrogenation reaction step, the upper limit of the hydrogenation reaction is determined from the viewpoint that the hydrogenation reaction can proceed more efficiently, the conversion rate can be further improved, and the target compound can be obtained with a higher selectivity. In addition, from the viewpoint of further suppressing a decrease in selectivity due to decomposition or polymerization of the reaction product, the temperature is preferably 800°C or lower, more preferably 600°C or lower, and still more preferably 500°C or lower. , particularly preferably 400°C or lower.

Reaction time of hydrogenation reaction In the hydrogenation reaction step of the present disclosure, the reaction time of the hydrogenation reaction is, for example, when a gas phase flow system is adopted, the contact time of the raw material compound with the catalyst (W/F) [W : weight of metal catalyst (g), F: flow rate of raw material compound (cc/sec)], the conversion rate due to the hydrogenation reaction is particularly high, and the target compound can be obtained in higher yield and higher selectivity. From the standpoint of performance, it is preferably 1 g·sec./cc to 120 g·sec./cc, more preferably 3 g·sec./cc to 100 g·sec./cc, and even more preferably 5 g·sec. ./cc ~ 80g・sec./cc. The above W/F specifically specifies the reaction time when a gas phase flow reaction is adopted.

Even when a batch reaction is employed, the contact time can be set appropriately.

The above-mentioned contact time means the time during which the raw material compound (substrate) and the catalyst are in contact with each other.

Reaction pressure for hydrogenation reaction In the hydrogenation reaction step of the present disclosure, the reaction pressure for hydrogenation reaction is preferably -0.05 MPa to 2 MPa, and more Preferably it is -0.01 MPa to 1 MPa, more preferably normal pressure to 0.5 MPa.

In this disclosure, if there is no particular description of pressure, pressure is gauge pressure.

Reaction container for hydrogenation reaction In the hydrogenation reaction step of the present disclosure, the reactor in which the raw material compound and the catalyst are introduced and the hydrogenation reaction is performed can have any shape and structure as long as it can withstand the above temperature and pressure. Not particularly limited. The reactor for the hydrogenation reaction is preferably a vertical reactor, a horizontal reactor, a multi-tubular reactor, or the like. The material of the reactor for the hydrogenation reaction is preferably glass, stainless steel, iron, nickel, iron-nickel alloy, or the like.

Gas phase reaction The hydrogenation reaction step of the present disclosure is preferably a flow type or batch method in which a raw material compound (substrate) is continuously charged into a reactor and a target compound is continuously extracted from the reactor by gas phase reaction. It can be implemented using any of the following methods.

The reaction is preferably carried out in a flow system to prevent the target compound from remaining in the reactor and the reaction to proceed excessively.

Gas phase continuous flow system The hydrogenation reaction step of the present disclosure is preferably carried out in a gas phase, more preferably carried out in a gas phase continuous flow system using a fixed bed reactor. When carried out using a gas phase continuous flow system, the equipment, operation, etc. can be simplified and it is economically advantageous.

In the hydrogenation reaction step, the atmosphere during the hydrogenation reaction is preferably an inert gas atmosphere, a hydrogen fluoride gas atmosphere, etc. from the viewpoint of suppressing deterioration of the catalyst. The inert gas is preferably nitrogen, helium, argon, etc. Among the inert gases, nitrogen is preferably used from the viewpoint of reducing costs. The concentration of the inert gas is preferably between 0% and 50% by mole of the gaseous components introduced into the reactor.

When the hydrogenation reaction process is carried out in the gas phase in the presence of a catalyst, the target compound can be obtained with a higher selectivity by adjusting the reaction temperature and reaction time (contact time) appropriately depending on the catalyst. I can do things.

(3) Target compound The target compound of the present disclosure has the general formula (1):

(In the formula, R ¹ , R ² , and R ³ are the same or different and represent fluorine or a perfluoroalkyl group.)
It is an alkene (hydrogenated alkene) represented by

Through the hydrogenation reaction step, X (halogen atom) of the raw material compound represented by general formula (2) is replaced with hydrogen to produce a hydrogen-substituted alkene.

In formula (1) of the alkene, R ¹ , R ² and R ³ are the same or different and represent fluorine or a perfluoroalkyl group.

A perfluoroalkyl group is an alkyl group in which all hydrogen atoms are replaced with fluorine atoms. The perfluoroalkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, even more preferably 1 to 6 carbon atoms, particularly preferably 1 to 4 carbon atoms, and most preferably carbon atoms. It is a perfluoroalkyl group of number 1 to 3.

The perfluoroalkyl group is preferably a linear or branched perfluoroalkyl group. The perfluoroalkyl group is preferably a trifluoromethyl group (CF ₃ -) and a pentafluoroethyl group (C ₂ F ₅ -).

The alkene represented by the general formula (1) of the target compound can be hydrogenated efficiently by the alkene (halogen atom) represented by the general formula (2) of the raw material compound in the presence of a palladium-supported activated carbon catalyst. It is preferable to use a compound with 2 carbon atoms (C ₂ compound) to a compound with 8 carbon atoms (C ₈ compound) in that hydrogenated alkenes can be produced with high conversion rate, yield and/or high selectivity. More preferably, it is a (C ₂ compound to C ₄ compound), and still more preferably a C ₄ compound.

The alkene represented by the general formula (1) of the target compound can be efficiently converted into hydrogen by converting the alkene (halogen atom) represented by the general formula (2) of the raw material compound into hydrogen in the presence of a palladium-supported activated carbon catalyst. Preferably, R ¹ , R ² , and R ³ are the same or different and are fluorine. , or a perfluoroalkyl group.

The alkene represented by general formula (1) of the target compound is preferably 1,1,1,2,4,4,4-heptafluoro-2-butene.

The alkene represented by the general formula (1) as a raw material compound can be used alone or in combination of two or more. Commercially available alkenes may also be used.

Preferred Hydrogenation Reaction The hydrogenation reaction step of the present disclosure preferably uses a palladium-supported activated carbon catalyst to hydrogenate perfluoro-2-butene as an alkene as a raw material compound, and converts 1, Produces 1,1,2,4,4,4-heptafluoro-2-butene.

After the hydrogenation reaction is completed, the target compound can be obtained by performing a purification treatment according to a conventional method, if necessary.

(4) Composition containing an alkene In a preferred embodiment, the composition of the present disclosure includes:
CF ₃ -CF=CH-CF ₃ (1,1,1,2,4,4,4-heptafluoro-2-butene);
CF ₃ -CFH-CFH-CF ₃ ; and
Contains CF ₃ -CFH-CFH-CF ₂ H;

The composition is preferably used as an etching gas, refrigerant, heat transfer medium, deposit gas, building block for organic synthesis, or cleaning gas.

By the production method of the present disclosure, an alkene represented by general formula (1) can be obtained. It may also be obtained in the form of a composition containing a target compound, an alkene represented by general formula (1), and a raw material compound, an alkene represented by general formula (2).

CF ₃ -CFH-CFH-CF ₃ contained in the composition is, for example, an alkane compound derived from the raw material compound perfluoro-2-butene.

CF ₃ -CFH-CFH-CF ₂ H contained in the composition is, for example, a 3H alkane compound.

In the composition, the content of 1,1,1,2,4,4,4-heptafluoro-2-butene is preferably 80 mol% or more and 99.9 mol% or less, with the total amount of the composition being 100 mol%. Yes, more preferably 90 mol% or more and 99.9 mol% or less, still more preferably 95 mol% or more and 99.9 mol% or less, particularly preferably 99 mol% or more and 99.9 mol% or less. When the total amount is 100 mol%, the content of CF ₃ -CF=CH-CF ₃ is preferably 80 mol % or more, and the content of CF ₃ -CFH-CFH-CF ₃ and CF ₃ -CFH-CFH-CF ₂ H is preferably 80 mol% or more. The content is preferably 20 mol% or less.

According to the production method of the present disclosure, 1,1,1,2,4,4,4-heptafluoro-2-butene (hydrogenated alkene) can be obtained with a particularly high selectivity, and as a result, , it is possible to reduce the amount of components other than 1,1,1,2,4,4,4-heptafluoro-2-butene in the composition. Therefore, according to the production method of the present disclosure, purification to obtain 1,1,1,2,4,4,4-heptafluoro-2-butene can be efficiently performed.

The composition is preferably used as an etching gas, coolant, heat transfer medium, etc. for forming advanced microstructures in semiconductors, liquid crystals, etc. A composition containing an alkene can preferably be effectively used for various purposes such as a deposit gas, a building block for organic synthesis, and a cleaning gas.

A deposit gas is a gas that deposits an etch-resistant polymer layer.

A building block for organic synthesis means a substance that can be a precursor of a compound having a highly reactive skeleton. When a composition containing 1,1,1,2,4,4,4-heptafluoro-2-butene is reacted with a fluorine-containing organosilicon compound such as CF ₃ Si(CH ₃ ) ₃ , CF ₃ groups, etc. By introducing a fluoroalkyl group, it is possible to convert it into a substance that can be used as a detergent or a fluorine-containing pharmaceutical intermediate.

The embodiments of the present disclosure have been described above.

The embodiments of the present disclosure are capable of various changes in form and detail without departing from the spirit and scope of the claims.

The present disclosure will be specifically explained with reference to Examples below.

The present disclosure is not limited in any way by these examples.

Example raw material compound: perfluoro-2-butene (F ₃ C-CF=CF-CF ₃ )
Target compound: 1,1,1,2,4,4,4-heptafluoro-2-butene (F ₃ C-CF=CH-CF ₃ )
((Z/E)-1327myz))
Gas chromatography: Manufactured by Shimadzu Corporation, product name “GC-2014”
NMR: Manufactured by JEOL, product name “400YH”

A SUS pipe (outer diameter: 1/2 inch) was used as a reaction tube, and it was filled with a palladium-supported activated carbon catalyst. After drying at 200°C for 3 hours in a nitrogen atmosphere, the temperature was raised to 400°C. After raising the temperature to 400°C, the temperature was lowered to the reaction temperature, hydrogen diluted with nitrogen was passed through, the hydrogen concentration was gradually increased, and finally the catalyst was hydrogenated with 100% hydrogen.

A gas phase flow reaction was carried out, the pressure was set to normal pressure, and the contact time (W/F ₀ ) between perfluoro-2-butene (raw material compound) and palladium-supported activated carbon catalyst (1%Pd/C) was set to 8 g. sec/cc (%), 17g sec/cc (%), 38g sec/cc (%), 60g sec/cc (%), or 78g sec/cc (%). The raw material compound was distributed to

The amount of hydrogen used was H ₂ /alkene molar ratio: 1.1.

( _H2 : 1.1 mol, alkene mol: 1 mol)
The reactor was heated to 200°C, 300°C, or 400°C to initiate the hydrogenation reaction of fluorine atoms. One hour after starting the hydrogenation reaction, the distillate that had passed through the abatement tower was collected.

Thereafter, mass spectrometry was performed using gas chromatography/mass spectrometry (GC/MS), and structural analysis by NMR spectrum was performed using NMR.

After the reaction was completed, it was confirmed from the results of mass spectrometry and structural analysis that 1,1,1,2,4,4,4-heptafluoro-2-butene was produced as the target compound.

Alkane compound derived from perfluoro-2-butene (F ₃ C-FC=CF-CF ₃ ) as a raw material compound: CF ₃ -CFH-CFH-CF ₃ , 3H alkane compound: CF ₃ -CFH-CFH-CF _2H was generated.

The results of each example are shown in Table 1 below.

In Table 1, the contact time (W/F) refers to the rate at which the flowing raw material gas flows, that is, the time during which the catalyst and the raw material gas are in contact with each other.

From the results of the examples (Table 1), hydrogen was added to perfluoro-2-butene as a raw material compound in the presence of a palladium-supported activated carbon catalyst to perform a hydrogenation reaction, and the target compound was 1,1,1. ,2,4,4,4-heptafluoro-2-butene can be efficiently hydrogenated, and hydrogenated alkenes can be produced with high conversion, yield, and/or high selectivity. done. A particularly preferred embodiment is the use of palladium-supported activated carbon catalysts.

Claims (2)

A method for producing 1,1,1,2,4,4,4-heptafluoro-2-butene (CF ₃ -CF=CH-CF ₃ ) , comprising:
A step of hydrogenating perfluoro-2-butene (CF ₃ -CF=CF-CF ₃ ) in the gas phase in the presence of an activated carbon catalyst supporting a noble metal or rare metal,
The noble metal or rare metal is at least one noble metal or rare metal selected from the group consisting of palladium (Pd), platinum (Pt), rhodium (Rh), ruthenium (Ru), and manganese (Mn). Production method. CF ₃ -CF=CH-CF ₃ ;
CF ₃ -CFH-CFH-CF ₃ ; and
Contains CF ₃ -CFH-CFH-CF ₂ H;
A composition for use as an etching gas, as a refrigerant, as a heat transfer medium, as a deposit gas, as a building block for organic synthesis, or as a cleaning gas.