JP2023099721A - Alkene production method - Google Patents

Abstract

To produce a hydrogenated alkene by way of hydrogen substitution.SOLUTION: An alkene production method includes a step in which a hydrogenation reaction is performed in the presence of an activated carbon catalyst supporting a precious metal or a noble metal.SELECTED DRAWING: None

Description

The present disclosure relates to methods of making alkenes.

In Patent Document 1, in the presence of a catalyst consisting of palladium or platinum supported on activated carbon,
A process for preparing trifluoroethylene is disclosed comprising contacting chlorotrifluoroethylene with hydrogen.

Special Table 2013-534529

The present disclosure is directed to producing hydrogenated alkenes by hydrogen substitution.

The present disclosure includes the following configurations.

Section 1.
General formula (1):

(In the formula, R ¹ , R ² and R ³ are the same or different and represent a fluorine or 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 a fluorine or 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 production method comprising the step of hydrogenating an alkene represented by in the presence of an activated carbon catalyst supporting a noble metal or rare metal.

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

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

Section 4.
_CF3 -CF=CH- _CF3 ;
_CF3 -CFH-CFH- _CF3 ; and
A composition containing _CF3 -CFH-CFH- _CF2H ;

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, it is possible to efficiently produce hydrogenated alkenes through hydrogen substitution.

As used herein, "contain" is a concept that includes both "comprise," "consist essentially of," and "consist of." Further, in this specification, when a numerical range is indicated by "A to B", it means A or more and B or less.

As a result of extensive research, the present inventors have found that the hydrogenation reaction can proceed efficiently by carrying out the hydrogenation reaction of the alkene, which is a raw material compound, in the presence of a palladium-supported activated carbon catalyst. , 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 such findings.

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 a fluorine or 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 a fluorine or 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.)
In the presence of an activated carbon catalyst supporting a noble metal or rare metal, the alkene represented by is subjected to a hydrogenation reaction.

In the production method of the present disclosure, the hydrogenation step is preferably carried out in the gas phase.

In the production method of the present disclosure, preferably, the noble metal or rare metal is 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 compositions of the present disclosure are
_CF3 -CF=CH- _CF3 ;
_CF3 -CFH-CFH- _CF3 ; and
_CF3 -CFH-CFH- _CF2H ;

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

According to the present disclosure, by satisfying the above requirements, the hydrogenation reaction proceeds efficiently, and a hydrogenated alkene can be produced with high conversion (yield) and high selectivity.

In the present disclosure, the “conversion rate” refers to the molar amount of the raw material compound (alkene containing a halogen atom) supplied to the reactor, and the compound other than the raw material compound contained in the outflow gas from the reactor outlet (hydrogenated alkene, etc.) is the ratio (mol%) of the total molar amount.

In the present disclosure, the "selectivity" refers to the target compound (hydrogenated alkene ) means the ratio (mol%) of the total molar amount.

The method for producing an alkene of the present disclosure can efficiently proceed with the hydrogenation reaction of an alkene containing a halogen atom, which is a raw material compound, and the hydrogenated alkene can be obtained with a high conversion rate (yield) and a high selectivity. It is possible to manufacture in

(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 a fluorine or 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.)
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, at least one of R ¹ , R ² and R ³ represents a perfluoroalkyl group.

Halogen atoms are preferably fluorine, bromine, iodine and chlorine atoms.

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

The perfluoroalkyl group is preferably a linear or branched perfluoroalkyl group. Perfluoroalkyl groups _are preferably trifluoromethyl groups ( _CF3- ) and pentafluoroethyl groups ( _C2F5- ).

The alkene represented by the general formula (2) of the raw material compound is efficiently hydrogenated in the presence of an activated carbon catalyst supporting a noble or rare metal, and the hydrogenated alkene is converted into a high yield with a high conversion rate. It preferably has 2 to 8 carbon atoms, more preferably 2 to 4 carbon atoms, and still more preferably 4 carbon atoms in terms of production efficiency 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 a fluorine or perfluoroalkyl group.

The alkene represented by the general formula (2) of the starting compound is preferably perfluoro-2-butene ( _F3C -CF=CF- _CF3 ), perfluoro-1-butene ( _CF3 - _CF2- CF=CF ₂ ) and the like.

The alkene represented by the general formula (2) of the raw material compound can be used alone, or two or more of them can be used in combination. A commercially available alkene may also be used.

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

In the hydrogenation step, the alkene represented by the general formula (2), which is the raw material compound, can be produced into a hydrogenated alkene with a high conversion rate, yield and / or high selectivity, which is preferably , has 2 to 8 carbon atoms, more preferably 2 to 4 carbon atoms, and still more preferably 4 carbon atoms.

In the hydrogenation step, the alkene represented by the general formula (2) of the 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 a fluorine or perfluoroalkyl group in terms of high conversion, yield and/or high selectivity.

The alkene represented by the general formula (2) of the starting compound is preferably perfluoro-2-butene (CF ₃ -CF=CF-CF ₃ ), and the target compound to be hydrogenated is represented by the general formula (1) is preferably 1,1,1,2,4,4,4-heptafluoro-2-butene ( _CF3- CF=CH- _CF3 ) ((Z/E)-1327myz) ).

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

The hydrogenation step is preferably carried out in the 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). Precious or rare metals.

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. You get the effect of speed.

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

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

A wide range of known preparation methods can be used for preparing the catalyst. For example, a catalyst in which palladium metal is supported on an activated carbon carrier is produced by immersing the activated carbon carrier in a solution containing palladium metal, impregnating the carrier with this solution, and then, if necessary, 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, and the like.

Amount of hydrogen used (H ₂ /alkene molar ratio)
In the hydrogenation reaction step of the present disclosure, the amount of hydrogen used per 1 mol of alkene is , 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), still more preferably It 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 step of hydrogenation reaction of the present disclosure uses a palladium-supported activated carbon catalyst, and the lower limit of the reaction temperature is such that the hydrogenation reaction proceeds more efficiently from the raw material compound, and the conversion rate is increased. The temperature is preferably 100° C. or higher, more preferably 150° C. or higher, and still more preferably 200° C. or higher, from the viewpoint of further improving the temperature and obtaining the target compound with a higher selectivity.

In the hydrogenation step, the upper limit of the hydrogenation reaction is from the viewpoint that the hydrogenation reaction proceeds more efficiently, the conversion rate is further improved, and the target compound can be obtained with a higher selectivity. And from the viewpoint of further suppressing the decrease in selectivity due to the 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 less.

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 used, 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 of the hydrogenation reaction is particularly high, and the target compound can be obtained with high yield and high selectivity. From the point of view of being able to ./cc to 80g·sec./cc. The above W/F specifies the reaction time especially when the gas-phase flow reaction is adopted.

Also when adopting a batch type reaction, the contact time can be appropriately set.

The contact time means the time during which the raw material compound (substrate) and the catalyst are in contact.

Reaction pressure of hydrogenation reaction In the hydrogenation reaction step of the present disclosure, the reaction pressure of the hydrogenation reaction is preferably -0.05 MPa to 2 MPa from the viewpoint of more efficient hydrogenation reaction, and more The pressure is preferably -0.01 MPa to 1 MPa, more preferably normal pressure to 0.5 MPa.

In the present disclosure, pressure is gauge pressure unless otherwise specified.

Reaction Vessel for Hydrogenation Reaction In the hydrogenation reaction step of the present disclosure, the reactor in which the raw material compound and the catalyst are charged and the hydrogenation reaction is carried out can withstand the above temperature and pressure. It is not particularly limited. A reactor for the hydrogenation reaction is preferably a vertical reactor, a horizontal reactor, a multitubular 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 based on a gas phase reaction, in which the raw material compound (substrate) is continuously charged into the reactor, and the target compound is continuously withdrawn from the reactor. It can be implemented by any method of the formula.

In order to prevent the reaction from excessively progressing due to the target compound remaining in the reactor, the reaction is preferably carried out in a flow system.

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

In the hydrogenation reaction step, the atmosphere in which the hydrogenation reaction is performed is preferably an inert gas atmosphere, a hydrogen fluoride gas atmosphere, or the like, from the viewpoint of suppressing deterioration of the catalyst. The inert gas is preferably nitrogen, helium, argon, or the like. Among the inert gases, nitrogen is preferably used from the viewpoint of cost reduction. The inert gas concentration is preferably between 0 mol % and 50 mol % of the gaseous components introduced into the reactor.

When the hydrogenation reaction is carried out in the gas phase in the presence of a catalyst, the desired compound can be obtained at a higher selectivity by adjusting the reaction temperature and reaction time (contact time) according to 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 a fluorine or perfluoroalkyl group.)
is an alkene (hydrogenated alkene) represented by

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

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

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

The perfluoroalkyl group is preferably a linear or branched perfluoroalkyl group. Perfluoroalkyl groups _are preferably trifluoromethyl groups ( _CF3- ) and pentafluoroethyl groups ( _C2F5- ).

The alkene represented by the general formula (1) of the target compound undergoes an efficient hydrogenation reaction of the alkene (halogen atom) represented by the general formula (2) of the starting compound in the presence of a palladium-supported activated carbon catalyst. A compound with 2 carbon atoms (C ₂ compound) to a compound with 8 carbon atoms (C ₈ compound) is preferable in that hydrogenated alkenes can be produced with high conversion rate, yield and/or high selectivity. Yes, more preferably ( _C2 to _C4 compounds, still more preferably _C4 compounds.

The alkene represented by the general formula (1) of the target compound is converted to the alkene (halogen atom) of the starting compound represented by the general formula (2) in the presence of a palladium-supported activated carbon catalyst. Preferably, R ¹ , R ² , and R ³ are the same or different, and fluorine , or represents 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) of the raw material compound can be used alone, or two or more of them can be used in combination. A commercially available alkene may also be used.

Preferred hydrogenation reaction In the hydrogenation reaction step of the present disclosure, preferably, a palladium-supported activated carbon catalyst is used to hydrogenate perfluoro-2-butene as the alkene of the starting compound, and 1, Produces 1,1,2,4,4,4-heptafluoro-2-butene.

After completion of the hydrogenation reaction, purification treatment can be performed according to a conventional method as necessary to obtain the desired compound.

(4) A composition containing an alkene The composition of the present disclosure comprises, as a preferred embodiment,
_CF3 -CF=CH- _CF3 (1,1,1,2,4,4,4-heptafluoro-2-butene);
_CF3 -CFH-CFH- _CF3 ; and
_CF3 -CFH-CFH- _CF2H ;

The compositions are preferably used as etching gases, coolants, heat transfer media, depositing gases, building blocks for organic synthesis, or cleaning gases.

According to the production method of the present disclosure, an alkene represented by general formula (1) can be obtained. It may be obtained in the form of a composition containing the alkene represented by the general formula (1) as the target compound and the alkene represented by the general formula (2) as the starting compound.

CF ₃ -CFH-CFH-CF ₃ contained in the composition is, for example, an alkane compound derived from the starting 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%. 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, and particularly preferably 99 mol% or more and 99.9 mol% or less. Taking the total amount as 100 mol%, the content of _CF3 -CF=CH- _CF3 is preferably 80 mol% or more, and the content of _CF3 -CFH-CFH- _CF3 and _CF3 -CFH-CFH- _CF2H 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 particularly high selectivity, resulting in , it is possible to reduce 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 for obtaining 1,1,1,2,4,4,4-heptafluoro-2-butene can be efficiently performed.

The composition is preferably used as an etching gas, a coolant, a heat transfer medium, etc. for forming state-of-the-art microstructures such as semiconductors and liquid crystals. Compositions containing alkenes are preferably useful for various applications such as deposit gases, building blocks for organic synthesis, and cleaning gases.

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. can be converted into a substance that can be used as a detergent or a fluorine-containing pharmaceutical intermediate by introducing a fluoroalkyl group.

The embodiments of the present disclosure have been described above.

Embodiments of the present disclosure are capable of many changes in form and detail without departing from the spirit and scope of the claims.

EXAMPLES The present disclosure will be specifically described below with reference to examples.

The present disclosure is in no way limited 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 ( _F3C -CF=CH- _CF3 )
((Z/E)-1327myz))
Gas chromatography: manufactured by Shimadzu Corporation, product name "GC-2014"
NMR: JEOL, product name "400YH"

A SUS pipe (outer diameter: 1/2 inch) was used as a reaction tube and 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 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 8 g. sec/cc(%), 17g
The raw material compound was passed through the reactor so as to obtain •sec/cc (%), 38g·sec/cc (%), 60g·sec/cc (%), or 78g·sec/cc (%).

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 at 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 passed through the abatement tower was collected.

After that, gas chromatography/mass spectrometry (GC/MS) was used to perform mass analysis, and NMR was used to perform structural analysis by NMR spectrum.

After completion of the reaction, 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 ( _F3C -FC=CF- _CF3 ) as a raw material compound: _CF3- CFH-CFH- _CF3 , 3H alkane compound: _CF3 -CFH-CFH-CF _2H was generated.

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

In Table 1, the contact time (W/F) means how fast the raw material gas flows, that is, the time during which the catalyst and the raw material gas come into contact with each other.

From the results of 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 carry out a hydrogenation reaction. When producing ,2,4,4,4-heptafluoro-2-butene, the hydrogenation reaction can be performed efficiently, and the hydrogenated alkene can be produced with high conversion, yield and/or high selectivity. done. A particularly preferred embodiment is the use of a palladium on activated carbon catalyst.

Claims (5)

General formula (1):

(In the formula, R ¹ , R ² and R ³ are the same or different and represent a fluorine or 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 a fluorine or 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 production method comprising the step of hydrogenating an alkene represented by in the presence of an activated carbon catalyst supporting a noble metal or rare metal. 2. The production method according to claim 1, wherein the hydrogenating step is performed in a gas phase. The noble or rare metal is at least one noble or rare metal selected from the group consisting of palladium (Pd), platinum (Pt), rhodium (Rh), ruthenium (Ru), and manganese (Mn). 3. The production method according to claim 1 or 2. _CF3 -CF=CH- _CF3 ;
_CF3 -CFH-CFH- _CF3 ; and
A composition containing _CF3 -CFH-CFH- _CF2H ; 5. The composition according to claim 4, used as etching gas, coolant, heat transfer medium, depositing gas, building block for organic synthesis, or cleaning gas.