JP2014122172A - Production method of liquid crystal compound having -cf=cf2 terminal group - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method with high versatility, by which a compound having a -CF=CFterminal group useful as a liquid crystal material can be easily and efficiently obtained.SOLUTION: The production method of a compound expressed by formula (4):R-(A)-Z-(A)-Z-(A)-Z-(A)-Z-(A)-Z-A-(CH)-CHCH-CF=CFincludes the following first and second steps. In the first step, a compound expressed by formula (2):YXCFCFXis added to a compound expressed by formula (1):R-(A)-Z-(A)-Z-(A)-Z-(A)-Z-(A)-Z-A-(CH)-CH=CHto produce a compound expressed by formula (3):R-(A)-Z-(A)-Z-(A)-Z-(A)-Z-(A)-Z-A-(CH)-CHYCH-CFXCFX. In the second step, the compound expressed by formula (3) above described is reduced to produce the compound expressed by formula (4).

Description

The present invention relates to a simple and efficient method for producing a compound having a —CF═CF ₂ terminal group useful as a liquid crystal compound.

Liquid crystal elements include mobile devices such as mobile phones and PDAs, display devices for office automation equipment such as copiers and personal computer monitors, display devices for home appliances such as liquid crystal televisions, clocks, calculators, measuring instruments, automotive meters, It is used for applications such as cameras, and various performances such as a wide operating temperature range, a low operating voltage, high-speed response, and chemical stability are required.
In such a liquid crystal element, a material exhibiting a liquid crystal phase is used, but there is no compound that satisfies all of the above characteristics alone, and a liquid crystal compound or a non-liquid crystal compound having excellent characteristics has not been present. By mixing a plurality of liquid crystal compositions, a liquid crystal composition satisfying the required performance was obtained.

In addition, in various properties required for the compound used in the liquid crystal composition as described above, it has excellent compatibility with other liquid crystal materials or non-liquid crystal materials, is chemically stable, and is used for a liquid crystal element. In this case, it is important to have a high speed response over a wide temperature range and a low voltage drive.
In relation to this, Patent Document 1 describes a derivative having —CF═CF ₂ as a terminal group.

Examples of the method for producing a derivative having —CF═CF ₂ as a terminal group described in Patent Document 1 include the following.
_{C 3 H 7 -Cy-Cy-} CH 2 CH 2 Cl (2a-2)
↓ 1. + Li, DBB, THF
2. + CF ₂ = CF _{2
C 3 H 7 -Cy-Cy-} CH 2 CH 2 -CF = CF 2 (1a-2-1)

International Publication No. 2010/074071

However, in this production method, it may be difficult to obtain raw materials, and when preparing Li reagent and reacting CF ₂ = CF ₂ , it is necessary to have an ultra-low temperature reaction facility, and the solvent dilution rate is Due to its high batch efficiency, the batch efficiency was poor, and since a charge transfer agent such as di-tert-butylbiphenyl was required, its removal was complicated and the purification yield after the reaction was reduced.
An object of the present invention is to solve the above problems.
That is, an object of the present invention is to provide a highly versatile production method capable of easily and efficiently obtaining a compound having a —CF═CF ₂ terminal group useful as a liquid crystal material.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have made it possible to increase the target compound in a short process by a production method in which a halofluoroethane is allowed to act on a universally available vinyl derivative and then reduced. It was found to be obtained in a yield.

This invention provides the manufacturing method of the compound represented by following formula (4) which has the following 1st process and 2nd process.
1st process: The process of adding the compound represented by following formula (2) to the compound represented by following formula (1), and manufacturing the compound represented by following formula (3).
_{^{R 1 - (A 1) a}} -Z 1 - (A 2) b -Z 2 - (A 3) c -Z 3 - (A 4) d -Z 4 - (A 5) e -Z 5 -A 6 _{- (CH 2) n -CH =} CH 2 (1)
Y ¹ X ¹ CFCF ₂ X ² (2)
_{^{R 1 - (A 1) a}} -Z 1 - (A 2) b -Z 2 - (A 3) c -Z 3 - (A 4) d -Z 4 - (A 5) e -Z 5 -A 6 ^{_{- (CH 2) n -CHY 2}} CH 2 -CFX 1 CF 2 X 2 (3)
Second step: A step of producing a compound represented by the following formula (4) by reducing the compound represented by the formula (3).
_{^{R 1 - (A 1) a}} -Z 1 - (A 2) b -Z 2 - (A 3) c -Z 3 - (A 4) d -Z 4 - (A 5) e -Z 5 -A 6 _{- (CH 2) n -CH 2} CH 2 -CF = CF 2 (4)
[However, the symbols in the formulas (1) to (4) have the following meanings.
R ¹ : a hydrogen atom, a halogen atom, a cyano group, or an aliphatic hydrocarbon group having 1 to 20 carbon atoms. One or more —CH ₂ — in the aliphatic hydrocarbon group may be substituted with an etheric oxygen atom (—O—) or a thioetheric sulfur atom (—S—), and the aliphatic hydrocarbon group One or more hydrogen atoms therein may be substituted with a halogen atom.
A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ : independently of each other, a trans-1,4-cyclohexylene group, a 1,4-phenylene group or a 2,6-naphthylene group. One or more hydrogen atoms in the group may be substituted with a halogen atom, a cyano group, or an alkyl group having 1 to 10 carbon atoms. One or two ═CH— groups in the 1,4-phenylene group or the 2,6-naphthylene group may be substituted with a nitrogen atom, and the trans-1,4-cyclohexylene may be substituted. One or two —CH ₂ — groups in the group may be substituted with an etheric oxygen atom (—O—) or a thioetheric sulfur atom (—S—).
Z ¹ , Z ² , Z ³ , Z ⁴ and Z ⁵ : each independently a single bond or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. One or more —CH ₂ — in the aliphatic hydrocarbon group may be substituted with an etheric oxygen atom (—O—) or a thioetheric sulfur atom (—S—), and one or more —CH ₂ — ₂ CH ₂ — may be substituted with —COO— or —OCO—, and one or more hydrogen atoms may be substituted with a halogen atom.
a, b, c, d and e: 0 or 1 independently of each other.
X ¹ and X ^{2 are} each independently a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.
Y ¹ : bromine atom or iodine atom.
Y ² : hydrogen atom, bromine atom or iodine atom.
n: 0-10. ]

As the production method, the compound represented by the formula (1) is a compound represented by the following formula (1-1), and the compound represented by the formula (2) is represented by the following formula (2-1). A production method in which the compound represented by the formula (3) is a compound represented by the following formula (3-1) and the compound represented by the formula (4) is a compound represented by the following formula (4-1): preferable.
_{^{R 11 - (A 11) a}} -Z 11 - (A 21) b -Z 21 - (A 31) c -Z 31 - (A 41) d -Z 41 - (A 51) e -Z 51 -A 61 -(CH ₂ ) _n1 -CH = CH ₂ (1-1)
Y ¹¹ X ¹¹ CFCF ₂ X ²¹ (2-1)
_{^{R 11 - (A 11) a}} -Z 11 - (A 21) b -Z 21 - (A 31) c -Z 31 - (A 41) d -Z 41 - (A 51) e -Z 51 -A 61 ^{_{- (CH 2) n1 -CHY 21}} CH 2 -CFX 11 CF 2 X 21 (3-1)
_{^{R 11 - (A 11) a}} -Z 11 - (A 21) b -Z 21 - (A 31) c -Z 31 - (A 41) d -Z 41 - (A 51) e -Z 51 -A 61 _{- (CH 2) n1 -CH 2} CH 2 -CF = CF 2 (4-1)
[However, the symbols in formulas (1-1) to (4-1) have the following meanings.
R ¹¹ : a hydrogen atom, a fluorine atom, a chlorine atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group, a fluoroalkyl group, or a fluoroalkoxy group.
A ¹¹ , A ²¹ , A ³¹ , A ⁴¹ , A ⁵¹ and A ⁶¹ : independently of each other, a trans-1,4-cyclohexylene group, a 1,4-phenylene group or a 2,6-naphthylene group. One or more hydrogen atoms in the group may be substituted with a fluorine atom.
Z ¹¹ , Z ²¹ , Z ³¹ , Z ⁴¹ and Z ⁵¹ : each independently a single bond or an alkylene group having 1 to 4 carbon atoms. One or more —CH ₂ — in the alkylene group may be substituted with —O—, and one or more hydrogen atoms may be substituted with a fluorine atom.
a, b, c, d and e: 0 or 1 independently of each other. However, a + b + c + d + e is 1-3.
X ^{11 is a} chlorine atom or a fluorine atom.
X ²¹ : bromine atom or chlorine atom.
Y ¹¹ and Y ^{21 are} each independently a bromine atom or an iodine atom.
n ¹ : 0-5. ]

The present invention also provides a compound represented by the following formula (3).
_{^{R 1 - (A 1) a}} -Z 1 - (A 2) b -Z 2 - (A 3) c -Z 3 - (A 4) d -Z 4 - (A 5) e -Z 5 -A 6 ^{_{- (CH 2) n -CHY 2}} CH 2 -CFX 1 CF 2 X 2 (3)
Symbols in the formula (3) have the following meanings.
R ¹ : a hydrogen atom, a halogen atom, a cyano group, or an aliphatic hydrocarbon group having 1 to 20 carbon atoms. One or more —CH ₂ — in the aliphatic hydrocarbon group may be substituted with —O— or —S—, and one or more hydrogen atoms in the aliphatic hydrocarbon group may be halogen atoms. May be substituted.
A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ : independently of each other, a trans-1,4-cyclohexylene group, a 1,4-phenylene group or a 2,6-naphthylene group. One or more hydrogen atoms in the group may be substituted with a halogen atom, a cyano group, or an alkyl group having 1 to 10 carbon atoms. One or two ═CH— groups in the 1,4-phenylene group or the 2,6-naphthylene group may be substituted with a nitrogen atom, and the trans-1,4-cyclohexylene may be substituted. One or two —CH ₂ — groups in the group may be substituted with —O— or —S—.
Z ¹ , Z ² , Z ³ , Z ⁴ and Z ⁵ : each independently a single bond or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. One or more —CH ₂ — in the aliphatic hydrocarbon group may be substituted with —O— or —S—, and one or more hydrogen atoms may be substituted with a halogen atom.
a, b, c, d and e: 0 or 1 independently of each other.
X ¹ and X ^{2 are} each independently a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.
Y ² : hydrogen atom, bromine atom or iodine atom.
n: 0-10.

According to the present invention, can be obtained easily and efficiently a compound with useful -CF = CF ₂ end groups as the liquid crystal material, it is possible versatility to provide high manufacturing method.
In addition, the present invention can provide an intermediate useful in such a production method.

The present invention will be described.
Hereinafter, the compound represented by the formula (1) may be referred to as “compound (1)”, and the compounds represented by other formulas may also be denoted in the same manner.
In the compounds of the present specification, —O— and / or —S— are not linked.

<R ¹ >
In the compounds (1), (3) and (4), R ¹ has the same meaning as described above. Further, the halogen atom substitution and the —O— or —S— substitution may be simultaneously performed on the aliphatic hydrocarbon group.
Moreover, as an aliphatic hydrocarbon group, an alkyl group and an alkenyl group are preferable.
Moreover, as a halogen atom which substitutes an aliphatic hydrocarbon group, a chlorine atom or a fluorine atom is preferable, and a fluorine atom is especially preferable.
Further, when R ¹ is a halogen atom, a chlorine atom or a fluorine atom is preferable, and a fluorine atom is particularly preferable because stability and physical properties as a liquid crystal material are good.

Hereinafter, an alkyl group substituted with at least one of —O—, —S— and a halogen atom is referred to as a “substituted alkyl group”.
An alkenyl group substituted with at least one of an etheric oxygen atom, —O—, —S— and a halogen atom is referred to as a “substituted alkenyl group”.

Examples of the substituted alkyl group include an alkoxy group, an alkoxyalkyl group, an alkylthio group, an alkylthioalkyl group, a fluoroalkyl group, and a fluoroalkoxy group.
Examples of the substituted alkenyl group include an alkenyloxy group, an alkenylthio group, and a fluoroalkenyl group.

Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, and a pentyl group.
Examples of the alkoxy group include a methoxy group, an ethoxy group, and a propoxy group.
Examples of the alkoxyalkyl group include a methoxymethyl group and an ethoxymethyl group.
Examples of the alkylthio group include a methylthio group, an ethylthio group, and a propylthio group.
Examples of the alkylthioalkyl group include a methylthiomethyl group and an ethylthiomethyl group.
Examples of the fluoroalkyl group include a trifluoromethyl group and a pentafluoroethyl group.
Examples of the fluoroalkoxy group include a trifluoromethoxy group and a difluoromethoxy group.
Examples of the alkenyl group include a vinyl group, a 1-propenyl group, a 1-butenyl group, a 1-pentenyl group, a 3-butenyl group, and a 3-pentenyl group.
Examples of the alkenyloxy group include an allyloxy group.
Examples of the alkenylthio group include an allylthio group.
Examples of the fluoroalkenyl group include a 1,2,2-trifluorovinyl group.

R ¹ is preferably a hydrogen atom, a fluorine atom, a chlorine atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group, a fluoroalkyl group, or a fluoroalkoxy group.
R ¹ is more preferably a fluorine atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group, a fluoroalkyl group, or a fluoroalkoxy group.
R ¹ is particularly preferably a fluorine atom or an alkyl group having 2 to 5 carbon atoms because of its good physical properties as a liquid crystal material.

^{<A 1 ,A 2 ,A 3 ,A 4} ,A 5 OyobiA ^6>
In the compounds (1), (3) and (4), A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ have the same meaning as described above.

  Here, the substitution of a halogen atom, a cyano group or an alkyl group having 1 to 10 carbon atoms and the substitution of a nitrogen atom, —O— or —S— may be performed simultaneously on the same group.

In A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ , the group in which one or more hydrogen atoms in the group are substituted with halogen atoms is substituted with 1 or 2 fluorine atoms. And 1,4-phenylene group, 2,6-naphthylene group and the like.

Examples of the group in which one or two ═CH— groups in the 1,4-phenylene group are substituted with nitrogen atoms include 2,5-pyrimidinylene group, 2,5-pyridinylene group and the like.
In addition, as a group in which one or two —CH ₂ — groups in the trans-1,4-cyclohexylene group are substituted with —O— or —S—, 1,3-dioxane-2,5 -Diyl group, 1,3-dithian-2,5-diyl group and the like.

A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ are each independently a trans-1,4-cyclohexylene group, 1,4-phenylene group, or 2,6-naphthylene group. It is preferable that One or more hydrogen atoms in the group may be substituted with a fluorine atom.
A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ are more preferably independently of each other a trans-1,4-cyclohexylene group or a 1,4-phenylene group. preferable. One or more hydrogen atoms in the group may be substituted with a fluorine atom.
In addition, since A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ are independent from each other, the raw materials are easily available, and the physical properties as a liquid crystal material are good. Particularly preferred are -cyclohexylene group, 1,4-phenylene group, and 1,4-phenylene group substituted by 1 or 2 fluorine atoms.

Here, these cyclic groups have bonds at the 1-position and 4-position.
In the present specification, the right side of the cyclic group is the 1st position and the left side is the 4th position. For example, A ¹ in the compound (1) is the 1st position on the side bonded to Z ¹ and the 4th position on the side bonded to R ¹ .

<Z ¹ , Z ² , Z ³ , Z ⁴ and Z ⁵ >
In the compound (1), the compound (3) and the compound (4), Z ¹ , Z ² , Z ³ , Z ⁴ and Z ⁵ have the same meaning as described above.

Here, the substitution of a halogen atom and the substitution of —O— or —S— may be performed simultaneously on the same group.
Further, the aliphatic hydrocarbon group is preferably an alkylene group, an alkenylene group or an alkynylene group.
Moreover, as a halogen atom which substitutes an aliphatic hydrocarbon group, a chlorine atom or a fluorine atom is preferable, and a fluorine atom is especially preferable.

Examples of the alkylene group include — (CH ₂ ) ₂ —, — (CH ₂ ) ₄ — and the like.
Examples of the alkenylene group include —CH═CH—, — (CH ₂ ) ₂ —CH═CH—, —CH ₂ —CH═CH—CH ₂ —, —CH═CH— (CH ₂ ) ₂ — and the like. Can be mentioned.
Examples of the alkynylene group include —C≡C—, — (CH ₂ ) ₂ —C≡C—, and the like.
Examples of the alkylene group in which one or more hydrogen atoms in the group are substituted with fluorine atoms include —CHF—CHF—, — (CF ₂ ) ₂ —, — (CH ₂ ) ₃ —CF ₂ —, and the like. It is done.
Examples of the alkylene group in which one or more —CH ₂ — in the group is substituted with —O— or —S— include —CH ₂ O—, —OCH ₂ —, —CH ₂ S—, —SCH _2. -Etc.

Z ¹ , Z ² , Z ³ , Z ⁴ and Z ⁵ are preferably each independently a single bond or an alkylene group having 1 to 4 carbon atoms. One or more —CH ₂ — in the group may be substituted with —O—, and one or more hydrogen atoms in the group may be substituted with a fluorine atom.
Z ¹ , Z ² , Z ³ , Z ⁴ and Z ⁵ are more preferably independently of each other a single bond or an alkylene group having 1 to 4 carbon atoms. One or more hydrogen atoms in the group may be substituted with a fluorine atom.
Z ¹ , Z ² , Z ³ , Z ^4, and Z ⁵ are chemically stable and have good physical properties as a liquid crystal material, so that they are independent of each other from a single bond, — (CH ₂ ) ₂ -, or - (CF _{2) 2} - and particularly preferably.

<A, b, c, d and e>
In the compounds (1), (3) and (4), a, b, c, d and e have the same meaning as described above.
Here, a + b + c + d + e is preferably 1 to 3 because preferable physical properties can be obtained as a liquid crystal material.
Further, a + b + c + d + e is particularly preferably 1 or 2.

<Other symbols>
In the compounds (1), (3) and (4), n has the same meaning as described above. n is preferably 0 to 5, more preferably 0 to 2, and particularly preferably 0 or 2 since the clearing point (Tc) is high in the compound (4).
In the compound (2) and the compound (3), X ¹ has the same meaning as described above, and is easily available and inexpensive. Therefore, a chlorine atom or a fluorine atom is preferable, and a fluorine atom is particularly preferable.
In compound (2) and compound (3), X ² represents the same meaning as described above, and is preferably a bromine atom or a chlorine atom, and is preferably a bromine atom because it is readily available and has good reactivity.
In the compounds (2) and (3), Y ¹ and Y ² have the same meaning as described above. As Y ¹ and Y ² , a bromine atom or an iodine atom is preferable, and a bromine atom is particularly preferable because it is easily available and has good reactivity.
In the first step of the production method of the present invention, by using a hydrogen source described later, Y ² may be a hydrogen atom and may be an atom different from Y ¹ .

In the production method of the present invention, the compound (1) is the following compound (1-1), the compound (2) is the following compound (2-1), and the compound (3) is the following compound (3-1). And the compound (4) is preferably the following compound (4-1).
_{^{R 11 - (A 11) a}} -Z 11 - (A 21) b -Z 21 - (A 31) c -Z 31 - (A 41) d -Z 41 - (A 51) e -Z 51 -A 61 -(CH ₂ ) _n1 -CH = CH ₂ (1-1)
Y ¹¹ X ¹¹ CFCF ₂ X ²¹ (2-1)
_{^{R 11 - (A 11) a}} -Z 11 - (A 21) b -Z 21 - (A 31) c -Z 31 - (A 41) d -Z 41 - (A 51) e -Z 51 -A 61 ^{_{- (CH 2) n1 -CHY 21}} CH 2 -CFX 11 CF 2 X 21 (3-1)
_{^{R 11 - (A 11) a}} -Z 11 - (A 21) b -Z 21 - (A 31) c -Z 31 - (A 41) d -Z 41 - (A 51) e -Z 51 -A 61 _{- (CH 2) n1 -CH 2} CH 2 -CF = CF 2 (4-1)
[However, the symbols in formulas (1-1) to (4-1) have the following meanings.
R ¹¹ : a hydrogen atom, a fluorine atom, a chlorine atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group, a fluoroalkyl group, or a fluoroalkoxy group.
A ¹¹ , A ²¹ , A ³¹ , A ⁴¹ , A ⁵¹ and A ⁶¹ : independently of each other, a trans-1,4-cyclohexylene group, a 1,4-phenylene group or a 2,6-naphthylene group. One or more hydrogen atoms in the group may be substituted with a fluorine atom.
Z ¹¹ , Z ²¹ , Z ³¹ , Z ⁴¹ and Z ⁵¹ : each independently a single bond or an alkylene group having 1 to 4 carbon atoms. One or more non-continuous —CH ₂ — in the group may be substituted with —O—, and one or more hydrogen atoms in the group may be substituted with a fluorine atom.
a, b, c, d and e: 0 or 1 independently of each other. However, a + b + c + d + e is 1-3.
X ^{11 is a} chlorine atom or a fluorine atom.
X ²¹ : bromine atom or chlorine atom.
Y ¹¹ and Y ^{21 are} each independently a bromine atom or an iodine atom.
n ¹ : 0-5. ]

Next, the 1st process of the manufacturing method of this invention is demonstrated.
In the following, gas chromatography is denoted as “GC”, N, N-dimethylformamide as “DMF”, tetrahydrofuran as “THF”, dimethylsulfoxide as “DMSO”, and N, N-dimethylacetamide as “DMAc”. There is.

<First step>
The first step is a step for producing compound (3) by adding compound (2) to compound (1).

Here, the compound (1) as a starting material is available as a commercial product. Moreover, it can obtain by the method described in the book of organic synthesis, such as a new experimental chemistry course (Maruzen Co., Ltd. publication).
Compound (2) is available as a commercial product.

  The reaction conditions in the first step can be carried out by mixing compound (1) and compound (2) in the absence of a solvent or in a solvent by heating or by acting a radical initiator. The presence or absence of a solvent can be appropriately selected. When the substrate dissolves, no side reaction due to the solvent is present, and the absence of solvent is preferable because of high batch efficiency.

  As the solvent, it is desirable to use an aromatic compound, an aliphatic hydrocarbon, an alicyclic hydrocarbon, an aliphatic ether compound, a cyclic ether compound, or an aprotic polar solvent. For example, as an aromatic compound, benzene, toluene, and chlorobenzene are preferable. As the aliphatic hydrocarbon, hexane and heptane are preferable. As the alicyclic hydrocarbon, cyclohexane is preferable. As the aliphatic ether compound, diethyl ether, methyl-tert-butyl ether, ethylene glycol dimethyl ether, and diethylene glycol dimethyl ether are preferable. As the cyclic ether compound, THF and dioxane are preferable. As the aprotic polar solvent, DMF, DMSO, acetonitrile, and DMAc are preferable. As the protic polar solvent, methyl alcohol, ethyl alcohol, isopropyl alcohol, tert-butyl alcohol, and n-butyl alcohol are preferable. The reaction can also be carried out by mixing the solvent.

About the usage-amount of a solvent, what is necessary is just the quantity which can implement reaction safely and stably. From the viewpoint of stirring and batch efficiency, the amount is preferably in the range of 0 to 20 times by mass with respect to the compound (1).
The reaction temperature should just be temperature which can stir favorably. Although it depends on the structure of the compound, the range of −40 ° C. to 200 ° C., in which the raw material and the target product do not decompose and the radical initiator acts, is preferable.

  In order to complete the reaction, the amount of compound (2) used is preferably equal to or greater than that of compound (1), more preferably 1.0 to 6.5 equivalents.

As the radical initiator, organic peroxides, azo compounds, borane compounds, and inorganic salts can be used. For example, benzoyl peroxide, di-tert-butyl peroxide, 2'-azobisisobutyronitrile, 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis ( 2-Methylpropionamidine) dihydrochloride, 4,4′-azobis (4-cyanopentanoic acid), triethylborane, copper and sodium dithionite are preferred.
The addition amount of the radical initiator is preferably 0.001 equivalent or more with respect to the compound (1) in order to complete the reaction. More preferably, it is the range of 0.01-1.5 equivalent with respect to compound (1).

The first step can be carried out by adding not only a radical initiator but also a hydrogen source.
A silicon compound and / or a tin compound may be added as a hydrogen source. As silicon compounds, Ph ₂ SiH ₂ , (Me ₃ Si) ₃ SiH, Et ₃ SiH, and tin compounds are Bu ₃ SnH because they are easily available, have good reactivity, and have a good yield. preferable.

<Second step>
The second step is a step for producing compound (4) by reducing compound (3).

  The reaction conditions for the second step can be carried out by allowing a reducing agent to act on compound (3) in the absence of a solvent or in a solvent.

  As the solvent, it is desirable to use water, aromatic compounds, aliphatic hydrocarbons, alicyclic hydrocarbons, aliphatic ether compounds, cyclic ether compounds, aprotic polar solvents, and protic polar solvents. For example, as the aromatic compound, benzene, toluene, chlorobenzene, and bromobenzene are preferable. As the aliphatic hydrocarbon, hexane and heptane are preferable. As the alicyclic hydrocarbon, cyclohexane is preferable. As the aliphatic ether compound, diethyl ether, methyl-tert-butyl ether, ethylene glycol dimethyl ether, and diethylene glycol dimethyl ether are preferable. As the cyclic ether compound, THF and dioxane are preferable. As the aprotic polar solvent, DMF, DMSO, acetonitrile, and DMAc are preferable. As the protic polar solvent, methyl alcohol, ethyl alcohol, isopropyl alcohol, tert-butyl alcohol, and n-butyl alcohol are preferable. The reaction can also be carried out by mixing the solvent.

About the usage-amount of a solvent, what is necessary is just the quantity which can implement reaction safely and stably. From the viewpoint of stirring and batch efficiency, the amount is preferably in the range of 0 to 20 times by mass with respect to the compound (3).
The reaction temperature should just be temperature which can stir favorably. Although it depends on the structure of the compound, the range of 10 ° C to 200 ° C is preferable.

  In order to complete the reaction, the amount of the reducing agent used is preferably equivalent to or more, more preferably 1.0 to 6.5 equivalents relative to the compound (3).

  As the reducing agent, an alkyl metal reagent and / or a metal atom are preferable. Among these, alkyl lithium reagent, lithium, alkyl magnesium reagent, magnesium, manganese, iron, zinc, and copper are more preferable because they are easily available and have good reactivity.

  Hereinafter, the present invention will be described more specifically with reference to examples. The following examples are intended to illustrate the present invention without limiting the present invention.

A compound of the following formula (4a) was produced. In this compound (4), a = 1, b = c = d = e = 0, R ¹ is an n-propyl group, and A ¹ and A ⁶ are all trans-1,4-cyclohexylene groups. , Z ¹ , Z ² , Z ³ , Z ⁴ and Z ⁵ all correspond to a single bond and n = 0.
Compound (1a) was synthesized with reference to known methods such as Japanese Patent Application Laid-Open No. 08-170078, Japanese Patent Application Laid-Open No. 10-114690, New Experimental Chemistry Course (published by Maruzen Co., Ltd.).
In addition, compound (2a) purchased from Tokyo Chemical Industry Co., Ltd. was used.

[First step]
In a pressure vessel, 10.16 g of compound (1a), 23.05 g of compound (2a), and 1.35 g of benzoyl peroxide (25% water-containing product) were stirred at 90 ° C. for 4 hours. After cooling, hexane was added to the resulting crude oil, and the organic phase was washed with a 5% aqueous sodium bicarbonate solution and water and then dried to obtain 18.57 g of compound (3a).

[Second step]
Under a nitrogen stream, 2.14 g of zinc powder, 3.11 g of lithium bromide, 4.97 g of compound (3a) and 15 ml of THF were stirred for 1 day under reflux conditions. 7.2% hydrochloric acid and hexane were added and the organic phase was washed with 5% sodium bicarbonate, water and dried. The resulting crude product was purified by silica chromatography and recrystallization to obtain 1.59 g of compound (4a).
Phase sequence of compound (4a): C 7.4 Sm 53.9 I
C represents a crystalline phase, Sm represents a smectic phase, and I represents an isotropic phase.
The measurement results of various spectral data strongly supported the structure of the corresponding compound.
¹ H NMR (CDCl ₃ , δ): 2.3-2.2 (m, 2H), 1.76-1.67 (m, 8H), 1.42 (m, 2H), 1.33-1 .24 (m, 2H), 1.20-0.84 (br, 18H).
¹⁹ F NMR (CDCl 3, δ): −106.72 (m, 1F), −125.8 (m, 1F), −174.86 (m, 1F).
GC-MS M ^<+> : 316

Claims (3)

The manufacturing method of the compound represented by Formula (4) which has the following 1st process and 2nd process.
1st process: The process of adding the compound represented by Formula (2) to the compound represented by Formula (1), and manufacturing the compound represented by Formula (3).
_{^{R 1 - (A 1) a}} -Z 1 - (A 2) b -Z 2 - (A 3) c -Z 3 - (A 4) d -Z 4 - (A 5) e -Z 5 -A 6 _{- (CH 2) n -CH =} CH 2 (1)
Y ¹ X ¹ CFCF ₂ X ² (2)
_{^{R 1 - (A 1) a}} -Z 1 - (A 2) b -Z 2 - (A 3) c -Z 3 - (A 4) d -Z 4 - (A 5) e -Z 5 -A 6 ^{_{- (CH 2) n -CHY 2}} CH 2 -CFX 1 CF 2 X 2 (3)
Second step: A step of producing a compound represented by formula (4) by reducing a compound represented by formula (3).
_{^{R 1 - (A 1) a}} -Z 1 - (A 2) b -Z 2 - (A 3) c -Z 3 - (A 4) d -Z 4 - (A 5) e -Z 5 -A 6 _{- (CH 2) n -CH 2} CH 2 -CF = CF 2 (4)
[However, the symbols in the formulas (1) to (4) have the following meanings.
R ¹ : a hydrogen atom, a halogen atom, a cyano group, or an aliphatic hydrocarbon group having 1 to 20 carbon atoms. One or more —CH ₂ — in the aliphatic hydrocarbon group may be substituted with an etheric oxygen atom or a thioetheric sulfur atom, and one or more hydrogen atoms in the aliphatic hydrocarbon group may be a halogen atom. It may be substituted with an atom.
A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ : independently of each other, a trans-1,4-cyclohexylene group, a 1,4-phenylene group or a 2,6-naphthylene group. One or more hydrogen atoms in the group may be substituted with a halogen atom, a cyano group, or an alkyl group having 1 to 10 carbon atoms. One or two ═CH— groups in the 1,4-phenylene group or the 2,6-naphthylene group may be substituted with a nitrogen atom, and the trans-1,4-cyclohexylene may be substituted. One or two —CH ₂ — groups in the group may be substituted with an etheric oxygen atom or a thioetheric sulfur atom.
Z ¹ , Z ² , Z ³ , Z ⁴ and Z ⁵ : each independently a single bond or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. One or more —CH ₂ — in the aliphatic hydrocarbon group may be substituted with an etheric oxygen atom or a thioetheric sulfur atom, and one or more —CH ₂ CH ₂ — may be —COO— or — OCO- may be substituted, and one or more hydrogen atoms may be substituted with a halogen atom.
a, b, c, d and e: 0 or 1 independently of each other.
X ¹ and X ^{2 are} each independently a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.
Y ¹ : bromine atom or iodine atom.
Y ² : hydrogen atom, bromine atom or iodine atom.
n: 0-10. ] The compound represented by the formula (1) is a compound represented by the formula (1-1), the compound represented by the formula (2) is a compound represented by the formula (2-1), and the formula (3) The compound represented by formula (3-1), and the compound represented by formula (4) is the compound represented by formula (4-1).
_{^{R 11 - (A 11) a}} -Z 11 - (A 21) b -Z 21 - (A 31) c -Z 31 - (A 41) d -Z 41 - (A 51) e -Z 51 -A 61 -(CH ₂ ) _n1 -CH = CH ₂ (1-1)
Y ¹¹ X ¹¹ CFCF ₂ X ²¹ (2-1)
_{^{R 11 - (A 11) a}} -Z 11 - (A 21) b -Z 21 - (A 31) c -Z 31 - (A 41) d -Z 41 - (A 51) e -Z 51 -A 61 ^{_{- (CH 2) n1 -CHY 21}} CH 2 -CFX 11 CF 2 X 21 (3-1)
_{^{R 11 - (A 11) a}} -Z 11 - (A 21) b -Z 21 - (A 31) c -Z 31 - (A 41) d -Z 41 - (A 51) e -Z 51 -A 61 _{- (CH 2) n1 -CH 2} CH 2 -CF = CF 2 (4-1)
[However, the symbols in formulas (1-1) to (4-1) have the following meanings.
R ¹¹ : a hydrogen atom, a fluorine atom, a chlorine atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group, a fluoroalkyl group, or a fluoroalkoxy group.
A ¹¹ , A ²¹ , A ³¹ , A ⁴¹ , A ⁵¹ and A ⁶¹ : independently of each other, a trans-1,4-cyclohexylene group, a 1,4-phenylene group or a 2,6-naphthylene group. One or more hydrogen atoms in the group may be substituted with a fluorine atom.
Z ¹¹ , Z ²¹ , Z ³¹ , Z ⁴¹ and Z ⁵¹ : each independently a single bond or an alkylene group having 1 to 4 carbon atoms. One or more —CH ₂ — in the alkylene group may be substituted with an etheric oxygen atom, and one or more hydrogen atoms may be substituted with a fluorine atom.
a, b, c, d and e: 0 or 1 independently of each other. However, a + b + c + d + e is 1-3.
X ^{11 is a} chlorine atom or a fluorine atom.
X ²¹ : bromine atom or chlorine atom.
Y ¹¹ and Y ^{21 are} each independently a bromine atom or an iodine atom.
n ¹ : 0-5. ] A compound represented by formula (3).
_{^{R 1 - (A 1) a}} -Z 1 - (A 2) b -Z 2 - (A 3) c -Z 3 - (A 4) d -Z 4 - (A 5) e -Z 5 -A 6 ^{_{- (CH 2) n -CHY 2}} CH 2 -CFX 1 CF 2 X 2 (3)
[However, the symbols in formula (3) have the following meanings.
R ¹ : a hydrogen atom, a halogen atom, a cyano group, or an aliphatic hydrocarbon group having 1 to 20 carbon atoms. One or more —CH ₂ — in the aliphatic hydrocarbon group may be substituted with an etheric oxygen atom or a thioetheric sulfur atom, and one or more hydrogen atoms in the aliphatic hydrocarbon group may be a halogen atom. It may be substituted with an atom.
A ¹ , A ² , A ³ , A ⁴ , A ⁵ and A ⁶ : independently of each other, a trans-1,4-cyclohexylene group, a 1,4-phenylene group or a 2,6-naphthylene group. One or more hydrogen atoms in the group may be substituted with a halogen atom, a cyano group, or an alkyl group having 1 to 10 carbon atoms. One or two ═CH— groups in the 1,4-phenylene group or the 2,6-naphthylene group may be substituted with a nitrogen atom, and the trans-1,4-cyclohexylene may be substituted. One or two —CH ₂ — groups in the group may be substituted with an etheric oxygen atom or a thioetheric sulfur atom.
Z ¹ , Z ² , Z ³ , Z ⁴ and Z ⁵ : each independently a single bond or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. One or more —CH ₂ — in the aliphatic hydrocarbon group may be substituted with an etheric oxygen atom or a thioetheric sulfur atom, and one or more hydrogen atoms may be substituted with a halogen atom. .
a, b, c, d and e: 0 or 1 independently of each other.
X ¹ and X ^{2 are} each independently a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.
Y ² : hydrogen atom, bromine atom or iodine atom.
n: 0-10. ]