JP6413848B2 - Method for producing fluorine-containing symmetric olefin - Google Patents

Description

  The present invention relates to a novel method for producing a fluorine-containing symmetric olefin by olefin metathesis.

  A compound in which some or all of the hydrogen atoms in the olefin are substituted with fluorine atoms, that is, a fluorine-containing olefin is an industrially useful compound. Among these, particularly useful compounds are known for olefins in which the same substituent is bonded to two carbon atoms constituting a carbon-carbon double bond, that is, 1,2-disubstituted olefins. For example, 1,1,1,4,4,4-hexafluoro-2-butene (HFO-1336mzz) is a useful compound as a blowing agent. However, a method for easily and efficiently producing these compounds has not been established. For example, Patent Document 1 discloses a method for obtaining 1,1,1,4,4,4-hexafluoro-2-butene by hydrogenating hexafluoro-2-butyne in the presence of a Lindlar catalyst. . However, this method requires the use of a Lindlar catalyst containing a toxic lead compound. Moreover, it is necessary to manufacture in advance hexafluoro-2-butyne as a raw material.

  Therefore, if other fluorine-containing olefins such as 1,1,1,4,4,4-hexafluoro-2-butene can be easily and efficiently produced from industrially available fluorine-containing olefins, compared with existing methods. Can be a very useful synthesis technique.

  On the other hand, an olefin metathesis reaction (hereinafter sometimes simply referred to as “olefin metathesis”), which is a double bond recombination reaction using a metal catalyst, is widely used as a method for producing olefins having various substituents. However, since an electron-deficient olefin having an electron-withdrawing substituent has low reactivity, it is not easy to use it for olefin metathesis. For example, Non-Patent Document 2 examines the reactivity of olefins having various substituents, and describes that the reactivity of electron-deficient olefins is low. In fact, since olefins having halogen atoms such as fluorine atoms and chlorine atoms are also electron-deficient olefins, there are few reports used for olefin metathesis. For example, in Non-Patent Document 1, olefin metathesis of a ruthenium complex and vinylidene fluoride (ie, 1,1-difluoroethylene) was studied, but the expected products, ie, ethylene and tetrafluoroethylene, were not obtained at all. It has been.

International Publication No. 2009/142642

Trnka, T .; et al. , Angew. Chem. Int. Ed. 2001, 40, 3441-3444.

  Accordingly, an object of the present invention is to provide a method for easily and efficiently producing a symmetric fluorinated olefin from an asymmetric fluorinated olefin which is easily available industrially under mild conditions.

  As a result of earnest study, the present inventors have found that asymmetric fluorine-containing olefins are subjected to olefin metathesis reaction between asymmetric fluorine-containing olefins in the presence of a metal catalyst having a metal-carbon double bond, The present invention has been completed.

[1]
In the presence of the metal-carbene complex compound (10) having olefin metathesis reaction activity, one type of asymmetric fluorine-containing olefin having 3 or more carbon atoms is allowed to undergo olefin metathesis reaction, whereby one type of symmetry having 4 or more carbon atoms. A method for producing a fluorine-containing olefin.
[2]
The production method according to [1], wherein the metal in the metal-carbene complex compound (10) is ruthenium, molybdenum, or tungsten.
[3]
The production method according to [1] or [2], wherein the asymmetric fluorine-containing olefin is a compound represented by the following formula (21), and the symmetrical fluorine-containing olefin is a compound represented by the following formula (51).

However, the symbol in a formula represents the following meaning.
X ¹ is a functional group selected from the group consisting of the following functional group (iii) and functional group Rf, and X ² and X ³ are each independently the following functional group (i), functional group (ii), and functional group. A functional group selected from the group consisting of (iii) and functional group (iv), and X ¹ and X ² may be bonded to each other to form a ring.
Functional group (i): hydrogen atom.
Functional group (ii): a halogen atom.
Functional group (iii): a fluorine atom.
Functional group (iii): a monovalent hydrocarbon group having 1 to 20 carbon atoms.
Functional group (iv): C1-C20 monovalent hydrocarbon group containing 1 or more atoms selected from the group consisting of a halogen atom, oxygen atom, nitrogen atom, sulfur atom, phosphorus atom, and silicon atom.
Functional group Rf: (per) fluoroalkyl group having 1 to 20 carbon atoms, (per) fluoroalkyl group having 1 to 20 carbon atoms having an etheric oxygen atom between carbon atoms, or 5 to 5 carbon atoms 20 (per) fluoroaryl groups.
[4]
The asymmetric fluorinated olefin is 3,3,3-trifluoropropene and the symmetric fluorinated olefin is 1,1,1,4,4,4-hexafluoro-2-butene, or the asymmetric fluorinated olefin Any one of [1] to [3], wherein 2,3,3-trifluoropropene and the symmetrical fluorine-containing olefin is 1,1,2,3,4,4-hexafluoro-2-butene 2. The production method according to 1.

  According to the method for producing a symmetric fluorinated olefin according to the present invention, a symmetric fluorinated olefin can be produced simply and efficiently from an asymmetric fluorinated olefin which is industrially easily available by olefin metathesis.

Hereinafter, the present invention will be described in detail, but the present invention is not limited to the following embodiments, and can be arbitrarily modified without departing from the gist of the present invention. In addition, the present invention relates to olefin metathesis by a metal catalyst, and description of general features common to the prior art may be omitted.
In the present specification, the “compound represented by the formula (X)” may be simply referred to as “compound (X)”. Moreover, the wavy line in the structural formula of the compound means that one or both of the E / Z isomers are mixed.
“Asymmetric olefin” means an olefin that is not a symmetric olefin. “Symmetric olefin” means that the substituents bonded to the two carbon atoms constituting the olefin are the same. For example, in an olefin represented by a specific formula R ¹ R ² C═CR ³ R ⁴ , when R ¹ and R ³ are equal and R ² and R ⁴ are equal, or R ¹ and R ⁴ are If equal and R ² and R ³ are equal, the olefin is called a symmetric olefin. In the present specification, the symmetry is not considered even when the E-form and the Z-form in the olefin can be distinguished.
The “perhalogenated alkyl group” means a group in which all hydrogen atoms of an alkyl group are substituted with halogen atoms. The perhalogenated alkoxy group means a group in which all hydrogen atoms of the alkoxy group are substituted with halogen atoms. The same applies to the “perhalogenated alkoxy group” and the “perhalogenated aryl group”.
The term “(per) halogenated alkyl group” is used as a general term that combines a halogenated alkyl group and a perhalogenated alkyl group. That is, the group is an alkyl group having one or more halogen atoms. The same applies to the “(per) halogenated alkoxy group”, “(per) halogenated aryl group”, and “(per) halogenated aryloxy group”.
The “aryl group” means a monovalent group corresponding to a residue obtained by removing one hydrogen atom bonded to any one of carbon atoms forming an aromatic ring in an aromatic compound, The aryl group derived from the ring compound and the heteroaryl group derived from the heterocyclic compound are collectively used.
The number of carbon atoms of the hydrocarbon group means the total number of carbon atoms contained in the whole hydrocarbon group, and when the group has no substituent, the number of carbon atoms forming the hydrocarbon group skeleton is When the group has a substituent, the total number is obtained by adding the number of carbon atoms in the substituent to the number of carbon atoms forming the hydrocarbon group skeleton.

<Reaction mechanism>
The present invention relates to a method for producing a symmetric fluorine-containing olefin by olefin metathesis. For example, when an asymmetric olefin represented by the following formula (21) is reacted in the presence of a metal-carbene complex, a symmetric fluorine-containing olefin represented by the following formula (51) is produced by a reaction mechanism represented by the following scheme (I). Is obtained.
In addition, compounds (11) and (12), which are intermediates shown in the following scheme (I), are described as representative examples of metal-carbene complex compounds (10) having olefin metathesis reaction activity. Examples of the specific metal-carbene complex compound (10) include a ruthenium-carbene complex, a molybdenum-carbene complex, or a tungsten-carbene complex (hereinafter also collectively referred to as “metal-carbene complex”).

In the above scheme (I), [L] is a ligand, and M is ruthenium, molybdenum or tungsten.
X ¹ is a functional group selected from the group consisting of the following functional group (iii) and functional group Rf, and X ² and X ³ are each independently the following functional group (i), functional group (ii), and functional group. A functional group selected from the group consisting of (iii) and functional group (iv), and X ¹ and X ² may be bonded to each other to form a ring.
Functional group (i): hydrogen atom.
Functional group (ii): a halogen atom.
Functional group (iii): a fluorine atom.
Functional group (iii): a monovalent hydrocarbon group having 1 to 20 carbon atoms.
Functional group (iv): C1-C20 monovalent hydrocarbon group containing 1 or more atoms selected from the group consisting of a halogen atom, oxygen atom, nitrogen atom, sulfur atom, phosphorus atom, and silicon atom.
Functional group Rf: (per) fluoroalkyl group having 1 to 20 carbon atoms, (per) fluoroalkyl group having 1 to 20 carbon atoms having an etheric oxygen atom between carbon atoms, or 5 to 5 carbon atoms 20 (per) fluoroaryl groups.

  Olefin metathesis is reversible. That is, in Scheme (I), there is a reverse reaction (reaction represented by an arrow in the reverse direction). However, the details of this point will not be described. In addition, geometric isomers may exist for the olefin to be produced. However, the details of this point are strongly dependent on the individual reactions, and the explanation is omitted.

<Metal-carbene complex compound (10)>
As the metal-carbene complex compound (10), in the above scheme (I), the compound (11) and the compound (12) are shown as examples. However, two functions bonded to a carbon atom forming a double bond with the metal. Each group is independently a hydrogen atom, a halogen atom, a monovalent hydrocarbon group having 1 to 20 carbon atoms, or an atom selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, and a silicon atom As long as it is a monovalent hydrocarbon group having 1 to 20 carbon atoms and 1 or more thereof, these may be bonded to each other to form a ring.
Although the compound (10) plays a role as a catalyst in the production method according to the present invention, it means both a substance to be charged as a reagent and a substance generated during the reaction (catalytically active species). Here, the compound (10) is known to show catalytic activity when some of the ligands dissociate under the reaction conditions, and to show catalytic activity without dissociation of the ligands. However, any of them is not limited in the present invention. In general, since olefin metathesis proceeds while repeating coordination and dissociation of olefin to the catalyst, it is not always clear how many ligands other than olefin are coordinated on the catalyst during the reaction. Therefore, in this specification, [L] does not specify the number or type of ligands.

  Among the above catalysts, the compound whose metal is ruthenium is generally referred to as “ruthenium-carbene complex”, for example, Vougioukalakis, G. et al. C. et al. Chem. Rev. 2010, 110, 1746-1787. The ruthenium-carbene complex described in 1) can be used. Further, for example, a ruthenium-carbene complex commercially available from Aldrich or Umicore can be used.

Specific examples of the ruthenium-carbene complex include bis (triphenylphosphine) benzylidene ruthenium dichloride, bis (tricyclohexylphosphine) benzylidene ruthenium dichloride, bis (tricyclohexylphosphine) -3-methyl-2-butenylidene ruthenium dichloride, ( 1,3-diisopropylimidazol-2-ylidene) (tricyclohexylphosphine) benzylideneruthenium dichloride, (1,3-dicyclohexylimidazole-2-ylidene) (tricyclohexylphosphine) benzylideneruthenium dichloride, (1,3-dimesitylimidazole) -2-ylidene) (tricyclohexylphosphine) benzylidene ruthenium dichloride, (1,3-dimesityl-4,5-dihydroimidazole) 2-Ilidene) (tricyclohexylphosphine) benzylideneruthenium dichloride, [1,3-bis (2,6-diisopropylphenyl) -4,5-dihydroimidazol-2-ylidene] (tricyclohexylphosphine) benzylideneruthenium dichloride, [1 , 3-bis (2-methylphenyl) -4,5-dihydroimidazol-2-ylidene] (tricyclohexylphosphine) benzylideneruthenium dichloride, [1,3-dicyclohexyl-4,5-dihydroimidazol-2-ylidene] ( Tricyclohexylphosphine) benzylideneruthenium dichloride, bis (tricyclohexylphosphine) ethoxymethylideneruthenium dichloride, (1,3-dimesityl-4,5-dihydroimidazol-2-ylide) ) (Tricyclohexylphosphine) ethoxymethylidene ruthenium dichloride, (1,3-dimesityl-4,5-dihydroimidazol-2-ylidene) [bis (3-bromopyridine)] benzylidene ruthenium dichloride, (1,3-dimesityl- 4,5-dihydroimidazol-2-ylidene) (2-isopropoxyphenylmethylidene) ruthenium dichloride, (1,3-dimesityl-4,5-dihydroimidazol-2-ylidene) [(tricyclohexylphosphoranyl) methylidene ] Dichlororuthenium tetrafluoroborate, Umicore M2, Umicore M51, Umicore M52, Umicore M71 SIMes, Umicore M71 SIPr, Umicore M73 SIMes, Umicore M73 SIPr, etc., (1,3-Dimesityl-4,5-dihydroimidazol-2-ylidene) (tricyclohexylphosphine) benzylideneruthenium dichloride, (1,3-Dimesityl-4,5-dihydroimidazole-2- Ylidene) (2-isopropoxyphenylmethylidene) ruthenium dichloride, (1,3-dimesityl-4,5-dihydroimidazol-2-ylidene) [(tricyclohexylphosphoranyl) methylidene] dichlororuthenium tetrafluoroborate, Umicore M2 Umicore M51, Umicore M52, Umicore M71 SIMes, Umicore M71 SIPr, Umicore M73 SIMes, Umicore M73 SIPr are particularly preferable. Of the above complexes, the names beginning with “Umicore” are trade names of Umicore products.
In addition, the said ruthenium carbene complex may be used independently and may be used together 2 or more types. Further, if necessary, it may be supported on a carrier such as silica gel, alumina or polymer.

Among the above catalysts, the compound whose metal is molybdenum or tungsten is generally called “molybdenum-carbene complex” or “tungsten-carbene complex”. (Ed) Olefin Metathesis: Theory and Practice, Wiley, 2014. The molybdenum-carbene complex or tungsten-carbene complex described in 1) can be used. For example, a molybdenum-carbene complex or a tungsten-carbene complex commercially available from Aldrich or Strem can be used.
The molybdenum-carbene complex or the tungsten-carbene complex may be used alone or in combination of two or more. Further, if necessary, it may be supported on a carrier such as silica gel, alumina or polymer.

  Specific examples of the molybdenum-carbene complex are shown below. Me represents a methyl group, i-Pr represents an isopropyl group, t-Bu represents a tertiary butyl group, and Ph represents a phenyl group.

  Specific examples of the tungsten-carbene complex include the following compounds.

<Asymmetric fluorine-containing olefin>
In the present invention, one kind of asymmetric fluorine-containing olefin having 3 or more carbon atoms is subjected to olefin metathesis reaction (self-metathesis reaction). The asymmetric fluorine-containing olefin is preferably compound (21).
X ^{1 to} X ³ in the compound (21) are as defined above.
That is, X ¹ in the compound (21) is a fluorine atom, a (per) fluoroalkyl group having 1 to 20 carbon atoms, or a (per) fluoroalkyl group having 1 to 20 carbon atoms having an etheric oxygen atom between the carbon atoms. A functional group selected from the group consisting of a group and a (per) fluoroaryl group having 5 to 20 carbon atoms; X ² and X ³ are each independently a hydrogen atom; a halogen atom; a monovalent carbonization having 1 to 20 carbon atoms A hydrogen group; and a monovalent hydrocarbon group having 1 to 20 carbon atoms containing one or more atoms selected from the group consisting of a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, and a silicon atom; The functional group chosen. X ¹ and X ² may be bonded to each other to form a ring.
Of the above groups, the group having a carbon atom may have an etheric oxygen atom between the carbon atoms as described later.

However, the combination of X ^{1 to} X ³ is selected so that the compound (21) has 3 or more carbon atoms. Furthermore, since the target compound (51) described later has 4 or more carbon atoms, at least one of X ¹ and X ² is preferably a group having 1 or more carbon atoms.

The compound (21) preferably contains 3 or more fluorine atoms.
The compound (21) is preferably a monoolefin. That is, it is preferable that X ^{1 to} X ³ do not include an alkene structure and an alkyne structure.

  Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom and a chlorine atom are preferable from the viewpoint of availability.

  The monovalent hydrocarbon group having 1 to 20 carbon atoms is an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 5 to 20 carbon atoms, or an aryloxy group having 5 to 20 carbon atoms. In particular, methyl group, ethyl group, propyl group, phenyl group, methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, tert-butoxy group, (2-ethyl) hexyloxy group, or dodecyloxy group Is preferable from the viewpoint of availability. Further, the hydrocarbon group skeleton may be linear, branched or cyclic.

  The monovalent hydrocarbon group having 1 to 20 carbon atoms containing at least one atom selected from the group consisting of a halogen atom, oxygen atom, nitrogen atom, sulfur atom, phosphorus atom, and silicon atom preferably includes the atom. Examples thereof include an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 5 to 20 carbon atoms containing the atom, and an aryloxy group having 5 to 20 carbon atoms. In these preferred groups, halogen atoms may be bonded to at least some of the carbon atoms. That is, for example, it may be a (per) fluoroalkyl group or a (per) fluoroalkoxy group. Moreover, these preferable groups may have an etheric oxygen atom between carbon atoms. These preferable groups may have a substituent having an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, or a silicon atom. Examples of the substituent include an amino group, a nitrile group, a carboxyl group, an ester group (acyloxy group or alkoxycarbonyl group), a thioalkyl group, and a silyl group.

  As the (per) fluoroalkyl group having 1 to 12 carbon atoms, a (per) fluoroalkyl group having 1 to 8 carbon atoms is particularly preferable. Specifically, a trifluoromethyl group, a pentafluoroethyl group, or a heptafluoropropyl group is preferable from the viewpoint of availability. The alkyl group chain may be linear, branched or cyclic.

  As the C1-C12 (per) fluoroalkyl group having an etheric oxygen atom between carbon atoms, the C1-C8 having an etheric oxygen atom between the carbon atom and carbon atom is particularly preferable. A (per) fluoroalkyl group is preferred. Specifically, a difluoromethyl group, a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, a perfluorobutyl group, a perfluorohexyl group, and a perfluorooctyl group are preferable from the viewpoint of availability. The alkyl group chain may be linear, branched or cyclic.

  As the (per) fluoroaryl group having 5 to 20 carbon atoms, a (per) fluoroaryl group having 5 to 12 carbon atoms is particularly preferable. Specifically, a monofluorophenyl group or a pentafluorophenyl group is preferable, and a pentafluorophenyl group is particularly preferable from the viewpoint of availability.

Preferably, as a combination of X ^{1 to} X ³ , X ¹ is a functional group Rf; X ² is a functional group (i) or a functional group (ii); X ³ is a functional group (i) or a functional group (Ii) is a combination. That is, the compound (21) is preferably a terminal olefin from the viewpoint of reactivity.
More preferably, X ¹ is difluoromethyl group, trifluoromethyl group, pentafluoroethyl group, heptafluoropropyl group, perfluorobutyl group, perfluorohexyl group, perfluorooctyl group; X ² is hydrogen atom or fluorine atom; X ³ is A hydrogen atom;

  The compound (21) is preferably a compound specifically shown below.

—R ^PF in the above formula is a C 1-12 perfluoroalkyl group or a C 1-12 perfluoroalkyl group having an etheric oxygen atom between carbon atoms.

  More preferably, the compound (21) is specifically the compound shown below.

<Symmetric fluorine-containing olefin>
In the present invention, one kind of symmetrical fluorine-containing olefin having 4 or more carbon atoms is obtained as the target compound. As this symmetrical fluorine-containing olefin, the compound (51) is preferable. Compound (51) is in principle an internal olefin. Specific examples of the fluorine-containing compound (51) include the following compounds.

  The production method of the present invention comprises reacting 3,3,3-trifluoropropene as asymmetric fluorine-containing olefins, and 1,1,1,4,4,4-hexafluoro-2-butene as symmetrical fluorine-containing olefins. Or 1,2,2,3,4,4-hexafluoro-2-butene as a symmetric fluorinated olefin by reacting 2,3,3-trifluoropropene with each other as an asymmetric fluorinated olefin It is suitable when manufacturing. Of these hexafluorobutenes, the Z form is preferred because it is industrially applicable. For this reason, Z body can be mainly manufactured by using the catalyst which can manufacture Z body selectively as a catalyst. Alternatively, the E form may be converted to the Z form by a known method to produce the Z form.

<Manufacturing method>
The present invention relates to a method for producing a fluorinated olefin by olefin metathesis. Typically, the olefin metathesis is carried out by contacting an asymmetric fluorinated olefin of the same type with a metal-carbene complex, and a symmetric fluorination different from the raw material is carried out. A fluorine olefin is obtained.

As the raw material olefin (the above-mentioned compound (21)), both terminal and internal olefins can be used. Although the number of substituents on the double bond is not particularly limited, monosubstituted olefins and 1,2-disubstituted olefins are preferable in that they have high reactivity. The geometric isomerism on the double bond is not particularly limited. From the viewpoint of improving the yield of the target product, it is preferable to use deaerated and dehydrated olefin as a raw material. There is no particular limitation on the deaeration operation, but freeze deaeration and the like may be performed. Although there is no restriction | limiting in particular about dehydration operation, Usually, it is made to contact with a molecular sieve etc. For the olefin as a raw material, the degassing and dehydration operations are usually performed before contacting with the metal-carbene complex.
Moreover, since the olefin used as a raw material may contain a trace amount impurity (for example, a peroxide, hydrogen fluoride, etc.), you may refine | purify from the point of the target-product yield improvement. There is no particular limitation on the purification method. For example, it can be carried out according to the method described in the literature (Armarego, WLF et al., Purification of Laboratory Chemicals (Sixth Edition), 2009, Elsevier).

The metal-carbene complex may be added as a reagent or generated in the system.
When charging as a reagent, a commercially available metal-carbene complex may be used as it is, or a non-commercially available metal-carbene complex synthesized by a known method from a commercially available reagent may be used.
When it is generated in the system, a metal-carbene complex prepared from a metal complex as a precursor by a known method can be used in the present invention.

  Although there is no restriction | limiting in particular as the quantity of the metal-carbene complex to be used, About 0.0001-1 mol is normally used with respect to 1 mol of reference | standard olefin among the olefins used as a raw material, Preferably 0.001-0 About 2 moles are used.

  The metal-carbene complex to be used is usually charged into the reaction vessel as a solid, but may be charged after being dissolved or suspended in a solvent. There is no restriction | limiting in particular as a solvent used at this time in the range which does not exert a bad influence on reaction, An organic solvent, a fluorine-containing organic solvent, an ionic liquid, water etc. can be used individually or in mixture. In these solvent molecules, some or all of the hydrogen atoms may be substituted with deuterium atoms.

Examples of the organic solvent include aromatic hydrocarbon solvents such as benzene, toluene, o-, m-, p-xylene and mesitylene; aliphatic hydrocarbon solvents such as hexane and cyclohexane; dichloromethane, chloroform, 1, 2 -Halogen solvents such as dichloroethane, chlorobenzene, o-dichlorobenzene; ether solvents such as tetrahydrofuran, dioxane, diethyl ether, glyme, diglyme, and the like can be used. Examples of the fluorine-containing organic solvent include hexafluorobenzene, m-bis (trifluoromethyl) benzene, p-bis (trifluoromethyl) benzene, α, α, α-trifluoromethylbenzene, dichloropentafluoropropane, and the like. Can be used. As the ionic liquid, for example, various pyridinium salts, various imidazolium salts and the like can be used. Among the above solvents, benzene, toluene, o-, m-, p-xylene, mesitylene, dichloromethane, chloroform, chlorobenzene, o-dichlorobenzene, diethyl ether, dioxane, THF in terms of solubility of the metal-carbene complex. (Tetrahydrofuran), hexafluorobenzene, m-bis (trifluoromethyl) benzene, p-bis (trifluoromethyl) benzene, α, α, α-trifluoromethylbenzene, and mixtures thereof are preferred.
In addition, it is preferable to use a degassed and dehydrated solvent for improving the yield of the target product. There is no particular limitation on the deaeration operation, but freeze deaeration and the like may be performed. Although there is no restriction | limiting in particular about dehydration operation, Usually, it is made to contact with a molecular sieve etc. The degassing and dehydration operations are usually performed before contacting with the metal-carbene complex.

The atmosphere in which the olefin and the metal-carbene complex are brought into contact with each other is not particularly limited, but an inert gas atmosphere is preferable from the viewpoint of extending the life of the catalyst, and a nitrogen or argon atmosphere is particularly preferable. However, when using, as a raw material, an olefin that becomes a gas under reaction conditions, such as tetrafluoroethylene, it can be carried out in these gas atmospheres.
The phase for contacting the olefin and the metal-carbene complex is not particularly limited, but a liquid phase is usually used in view of the reaction rate. When the olefin as a raw material is a gas under the reaction conditions, it is difficult to carry out in the liquid phase, so it can also be carried out in the gas-liquid two phase. In the case of carrying out in the liquid phase, a solvent can be used. As the solvent used at this time, the same solvents as those used for dissolving or suspending the metal-carbene complex can be used. In addition, when at least one of the raw olefins is a liquid under the reaction conditions, it may be carried out without a solvent.

  The container for bringing the olefin into contact with the metal-carbene complex is not particularly limited as long as it does not adversely affect the reaction. For example, a metal container or a glass container can be used. In addition, since the olefin metathesis concerning this invention may handle the olefin in a gaseous state on reaction conditions, the pressure-resistant container which can be airtight is preferable.

Although there is no restriction | limiting in particular as temperature which contacts an olefin and a metal carbene complex, Usually, it can implement in the range of -100-200 degreeC, and 0-150 degreeC is preferable at the point of reaction rate. Note that the reaction does not start at low temperatures, and the complex may be rapidly decomposed at high temperatures. Therefore, it is necessary to appropriately set the lower limit and the upper limit of the temperature. Usually, it is carried out at a temperature below the boiling point of the solvent used.
The time for bringing the olefin into contact with the metal-carbene complex is not particularly limited, but is usually in the range of 1 minute to 48 hours.
The pressure for bringing the olefin into contact with the metal-carbene complex is not particularly limited, but may be under pressure, under normal pressure, or under reduced pressure. Usually, it is about 0.001-10 MPa, preferably about 0.01-1 MPa.

  When the olefin and the metal-carbene complex are brought into contact with each other, an inorganic salt, an organic compound, a metal complex, or the like may coexist within a range that does not adversely affect the reaction. Moreover, you may stir the mixture of an olefin and a metal carbene complex in the range which does not have a bad influence on reaction. At this time, a mechanical stirrer, a magnetic stirrer, or the like can be used as a stirring method.

  After contacting the olefin with the metal-carbene complex, the target product is usually obtained as a mixture of a plurality of olefins, and thus may be isolated by a known method. Examples of the isolation method include distillation, column chromatography, recycle preparative HPLC and the like, and these can be used alone or in combination as necessary.

The target product obtained in this reaction can be identified by a known method similar to that for ordinary organic compounds. For example, ¹ H-, ¹⁹ F-, ¹³ C-NMR, GC-MS and the like can be mentioned, and these can be used alone or in combination.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these.
<Commercially available reagents>
In this example, unless otherwise specified, a commercially available catalyst is used as it is for the reaction. The solvent (o-dichlorobenzene-d ₄ ) was used for the reaction after freezing and degassing a commercially available product in advance and then drying with molecular sieve 4A.
<Evaluation method>
In this example, the structure of the synthesized compound was identified by performing ¹ H-NMR and ¹⁹ F-NMR measurements using a nuclear magnetic resonance apparatus (JNM-AL300) manufactured by JEOL Ltd. Moreover, molecular weight was calculated | required by the electron ionization method (EI) using the Shimadzu Corporation gas chromatograph mass spectrometer (GCMS-QP2010Ultra).

<Example 1>
Synthesis of 1,1,1,4,4,4-hexafluoro-2-butene by metathesis of 3,3,3-trifluoropropene with Grubbs second generation catalyst Grubbs second generation catalyst (20 mol%) under nitrogen atmosphere 0.024 mmol) and o-dichlorobenzene-d ₄ (0.6 mL) were weighed into a pressure-resistant NMR measuring tube. Thereafter, the gas phase portion of the NMR measuring tube was replaced with 3,3,3-trifluoropropene (1.0 atm, 2.7 mL, 0.12 mmol).
The NMR measuring tube was heated at 180 ° C. and reacted at that temperature for 1 hour. After completion of the reaction, NMR and GC-MS of the content liquid were measured to confirm the formation of 1,1,1,4,4,4-hexafluoro-2-butene.
A series of these reactions is shown below.
GC-MS (EI): M ⁺ = 164

<Example 2>
Synthesis of 1,1,1,4,4,4-hexafluoro-2-butene by metathesis of 3,3,3-trifluoropropene with Hoveyda-Grubbs second generation catalyst Hoveyda-Grubbs second generation under nitrogen atmosphere Catalyst (20 mol%, 0.024 mmol) and o-dichlorobenzene-d ₄ (0.6 mL) were weighed into a pressure-resistant NMR measuring tube. Thereafter, the gas phase portion of the NMR measuring tube was replaced with 3,3,3-trifluoropropene (1.0 atm, 2.7 mL, 0.12 mmol).
The NMR measuring tube was heated at 180 ° C. and reacted at that temperature for 1 hour. After completion of the reaction, NMR and GC-MS of the content liquid were measured to confirm the formation of 1,1,1,4,4,4-hexafluoro-2-butene.
A series of these reactions is shown below.
GC-MS (EI): M ⁺ = 164

Claims (3)

In the presence of a metal-carbene complex compound having an olefin metathesis reaction activity, one asymmetric fluorine-containing olefin having 3 or more carbon atoms is allowed to undergo an olefin metathesis reaction to produce one kind of symmetrical fluorine-containing carbon having 4 or more carbon atoms. A method for producing olefins , comprising:
The production method, wherein the asymmetric fluorine-containing olefin is a compound represented by the following formula (21), and the symmetrical fluorine-containing olefin is a compound represented by the following formula (51).

However, the symbol in a formula represents the following meaning.
X ¹ is a functional group selected from the group consisting of a difluoromethyl group, a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, a perfluorobutyl group, a perfluorohexyl group, and a perfluorooctyl group, and X ² and X ³ is a functional group independently selected from the group consisting of the following functional group (i), functional group (ii), functional group (iii) and functional group (iv).
Functional group (i): hydrogen atom.
Functional group (ii): a halogen atom.
Functional group (iii): a monovalent hydrocarbon group having 1 to 20 carbon atoms.
Functional group (iv): C1-C20 monovalent hydrocarbon group containing 1 or more atoms selected from the group consisting of a halogen atom, oxygen atom, nitrogen atom, sulfur atom, phosphorus atom, and silicon atom. Metal - metal definitive carbene complex compound, ruthenium, molybdenum or tungsten Process according to claim 1. The asymmetric fluorinated olefin is 3,3,3-trifluoropropene and the symmetric fluorinated olefin is 1,1,1,4,4,4-hexafluoro-2-butene, or the asymmetric fluorinated olefin There is a 2,3,3-trifluoropropene, and symmetrically fluorinated olefin is 1,1,2,3,4,4- hexafluoro-2-butene the process according to claim 1 or 2 .