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JP4077103B2 - Method for producing tris (perfluoroalkylsulfonyl) methide salt - Google Patents

Method for producing tris (perfluoroalkylsulfonyl) methide salt Download PDF

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Publication number
JP4077103B2
JP4077103B2 JP02628699A JP2628699A JP4077103B2 JP 4077103 B2 JP4077103 B2 JP 4077103B2 JP 02628699 A JP02628699 A JP 02628699A JP 2628699 A JP2628699 A JP 2628699A JP 4077103 B2 JP4077103 B2 JP 4077103B2
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Japan
Prior art keywords
perfluoroalkylsulfonyl
tris
methide
methide salt
alkali metal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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JP02628699A
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JP2000226392A (en
Inventor
一男 森崎
正直 佐々木
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Kanto Denka Kyogyo Co.,Ltd.
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Kanto Denka Kyogyo Co.,Ltd.
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Description

【0001】
【発明の属する技術分野】
本発明は、ルイス酸触媒および有機イオン電導体として有用な物質である一般式(I)で示されるトリス(パーフルオロアルキルスルホニル)メチド塩の製造法に関するものである。
【0002】
【従来の技術】
トリス(パーフルオロアルキルスルホニル)メチド塩は、ルイス酸触媒や有機イオン電導体として有機合成および電気材料分野において有用な物質である。
これまでに提案されているトリス(パーフルオロアルキルスルホニル)メチド塩の製法としては、例えば、
▲1▼下記の如く、メチルマグネシウムハライド(グリニャー試薬)とパーフルオロアルキルスルホニルハライドとの反応によりビス(パーフルオロアルキルスルホニル)メタンを一旦合成した後、再び前記グリニャー試薬およびパーフルオロアルキルスルホニルハライドと反応させてトリス(パーフルオロアルキルスルホニル)メタンを合成し、更にアルカリ金属化合物と反応させる方法(WO92/02966,Inorg.Chem., 1988,27,2135.,J.Chem.Soc.Faraday Trans.,1993,89,355 等)
3CH3MgX + 2RfSO2X + HX → (RfSO2)2CH2 + 2CH4 + 3MgX2
(RfSO2)2CH2 + 2CH3MgX + RfSO2X + HX
→ (RfSO2)3CH + 2CH4 + 2MgX2
(RfSO2)3CH + MOR → (RfSO2)3CM + ROH
[式中、X はハロゲン、 Rf はパーフルオロアルキル基、M はアルカリ金属陽イオン、R は水素またはメチル基を表す。]
▲2▼上記ビス(パーフルオロアルキルスルホニル)メタンをアルカリ金属塩に変換した後、塩基存在下でフルオロアルキルスルホニルハライドと反応してトリス(パーフルオロアルキルスルホニル)メタン化合物を合成し、さらにアルカリ金属化合物と反応させる方法(USP5446134 等)
(RfSO2)2CH2 + MOR → (RfSO2)2CHM + ROH
(RfSO2)2CHM + RfSO2X + Et3N → (RfSO2)3CHNEt3 + MX
(RfSO2)3CHNEt3 + M2PO4 → (RfSO2)3CM + M(Et3NH)PO4
[式中、 Rf, M, R, X は前記定義の通りである。]
等が知られている。
しかしながら、上記▲1▼および▲2▼の方法は、いずれも非常に多くの工程を必要とする上に高価なグリニャー試薬を多量に使用することから、工業的な製法ではない。
以上のように、トリス(パーフルオロアルキルスルホニル)メチド塩の実用的な合成法については、満足のいく方法が見当たらないのが実情である。
【0003】
【発明が解決しようとする課題】
従って本発明の目的は、上記▲1▼および▲2▼の方法による問題点を解決し、トリス(パーフルオロアルキルスルホニル)メチド塩の簡便な工業的製法を提供するものである。
【0004】
【課題を解決するための手段】
本発明者らは、上記目的を達成するため鋭意検討した結果、メチド化剤としてアルカリ金属メタンを用いることによりトリス(パーフルオロアルキルスルホニル)メチド塩の簡便な製造法を見い出した。
本発明によれば、パーフルオロアルキルスルホニルハライドとアルカリ金属メタンからなる混合物を有機溶媒中で反応させることにより、一工程でトリス(パーフルオロアルキルスルホニル)メチド塩を製造することができる。
即ち、本発明は、
一般式(II):
RfSO2X …(II)
〔式中、X はハロゲンを表す。 Rf は炭素数1から6までの直鎖または分岐状のパーフルオロアルキル基を表す。〕
で示されるパーフルオロアルキルスルホニルハライドと、
一般式(III):
MCH3 …(III)
〔式中、M はアルカリ金属陽イオンを表す。〕
で示されるアルカリ金属メタンからなる混合物を有機溶媒中で反応させることにより、
一般式(I):
(RfSO2)3CM …(I)
〔式中、 Rf およびM は前記定義の通りである。〕
で表されるトリス(パーフルオロアルキルスルホニル)メチド塩を製造する方法である。
【0005】
【発明の実施の形態】
以下、本発明を詳細に説明する。
本発明において化合物(I)の製造に用いられる有機溶媒としては、(II)および(III)が可溶で、反応工程中で原料及び生成物と反応しない不活性溶媒が好ましく、例えば、ジエチルエーテル、テトラヒドロフラン、ジオキサン等のエーテル類が好適なものとして挙げられるが、これらに限定されるものではない。上記反応は−70℃から 150℃の温度範囲で行うことが可能であり、最適には、30℃から 100℃の温度範囲が好ましい。
【0006】
本発明の反応式は、次のように示される。
3RfSO2X + 4MCH3 → (RfSO2)3CM + 3LiX + 3CH3
[式中、 Rf は炭素数1から6までの直鎖または分岐状のパーフルオロアルキル基であり、好ましくはCF3 、C2F5、C3F7、C4F9である。X はハロゲン、M はアルカリ金属陽イオンであり、好ましくはLi+ 、Na+ 、K + である。]
上記 Rf としてはCF3 、C2F5、C3F7、C4F9が好ましく、またM としてはLi+ 、Na+ 、K + が好ましい。
【0007】
【実施例】
以下に実施例により本発明を更に詳細に説明するが、本発明はこれらの実施例に限定されるものではない。
実施例1[リチウムトリス(トリフルオロメタンスルホニル)メチドの製造]
コンデンサーを付した500mL 三口フラスコを窒素置換した後、1.4Mメチルリチウム/エーテル溶液300mL を仕込み、ドライアイス/エタノール浴上−55℃に冷却した。激しく攪拌しながら、トリフルオロメタンスルホニルクロライド53gを滴下した。その後、徐々に昇温し、沸騰還流下で7時間反応を行なった。
室温まで放冷した後、冷却しながら5%塩酸を加え十分攪拌を行なった。晶析した塩化リチウムおよび水酸化リチウムを濾別した。
濾液は、エーテルで抽出した後、飽和食塩水で洗浄した。有機層は、無水硫酸マグネシウムを加え1時間乾燥した後、孔径 0.2μm のメンブランフィルター(日本ミリポール社製)により減圧濾過した。濾液は、減圧下溶媒を留去した後、トルエンを加えて共沸脱水を行った。得られた結晶を 150℃で72時間乾燥を行った結果、リチウムトリス(トリフルオロメタンスルホニル)メチド:(CF3SO2)3CLi 13.5g(収率31%)を得た。
得られた物質の物性値は以下の通りであった。
融点: 268℃
13C−NMR(CD3CN ,δ):123.3, 119.1
19F−NMR(CD3CN ,δ):−77.5(S)
IR(kBr,cm-1):3500, 1645, 1377, 1202, 1124, 983, 769, 668, 625, , 576, 506, 445, 417, 406
実施例2
200mL ステンレス製オートクレーブを窒素置換した後、1.4Mメチルリチウム/エーテル溶液 100mLを仕込み、ドライアイス/エタノール浴上−75℃に冷却した。これにトリフルオロメタンスルホニルクロライド20gを添加した。その後徐々に昇温し、90℃、8.5 kg/cm2 で24時間反応を行なった。
実施例1と同様の処理を行なった結果、リチウムトリス(トリフルオロメタンスルホニル)メチド 8.1g(収率56%)を得た。
実施例3
トリフルオロメタンスルホニルフルオライドを使用し、実施例2と同様の条件で反応を行なった結果、リチウムトリス(トリフルオロメタンスルホニル)メチドを得た。収率は、42%であった。
[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a tris (perfluoroalkylsulfonyl) methide salt represented by the general formula (I) which is a substance useful as a Lewis acid catalyst and an organic ion conductor.
[0002]
[Prior art]
Tris (perfluoroalkylsulfonyl) methide salt is a useful substance in the field of organic synthesis and electrical materials as a Lewis acid catalyst and an organic ion conductor.
As a method for producing a tris (perfluoroalkylsulfonyl) methide salt proposed so far, for example,
(1) As described below, bis (perfluoroalkylsulfonyl) methane is once synthesized by reaction of methylmagnesium halide (Grigner reagent) and perfluoroalkylsulfonyl halide, and then reacted again with the Grignard reagent and perfluoroalkylsulfonyl halide. And tris (perfluoroalkylsulfonyl) methane to be synthesized and further reacted with an alkali metal compound (WO92 / 02966, Inorg. Chem., 1988, 27, 2135., J. Chem. Soc. Faraday Trans., 1993) , 89,355 etc.)
3CH 3 MgX + 2R f SO 2 X + HX → (R f SO 2 ) 2 CH 2 + 2CH 4 + 3MgX 2
(R f SO 2 ) 2 CH 2 + 2CH 3 MgX + R f SO 2 X + HX
→ (R f SO 2 ) 3 CH + 2CH 4 + 2MgX 2
(R f SO 2 ) 3 CH + MOR → (R f SO 2 ) 3 CM + ROH
[Wherein, X represents halogen, R f represents a perfluoroalkyl group, M represents an alkali metal cation, and R represents hydrogen or a methyl group. ]
(2) The above bis (perfluoroalkylsulfonyl) methane is converted to an alkali metal salt and then reacted with a fluoroalkylsulfonyl halide in the presence of a base to synthesize a tris (perfluoroalkylsulfonyl) methane compound. (USP 5446134 etc.)
(R f SO 2 ) 2 CH 2 + MOR → (R f SO 2 ) 2 CHM + ROH
(R f SO 2 ) 2 CHM + R f SO 2 X + Et 3 N → (R f SO 2 ) 3 CHNEt 3 + MX
(R f SO 2 ) 3 CHNEt 3 + M 2 PO 4 → (R f SO 2 ) 3 CM + M (Et 3 NH) PO 4
[Wherein R f , M, R and X are as defined above. ]
Etc. are known.
However, the methods {circle around (1)} and {circle around (2)} are not industrial production methods because they require a large number of steps and a large amount of expensive Grignard reagent is used.
As described above, there is no satisfactory method for practical synthesis of tris (perfluoroalkylsulfonyl) methide salt.
[0003]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to solve the problems caused by the methods (1) and (2) and to provide a simple industrial process for producing a tris (perfluoroalkylsulfonyl) methide salt.
[0004]
[Means for Solving the Problems]
As a result of intensive studies to achieve the above object, the present inventors have found a simple method for producing a tris (perfluoroalkylsulfonyl) methide salt by using alkali metal methane as a methidizing agent.
According to the present invention, a tris (perfluoroalkylsulfonyl) methide salt can be produced in one step by reacting a mixture of perfluoroalkylsulfonyl halide and alkali metal methane in an organic solvent.
That is, the present invention
General formula (II):
R f SO 2 X (II)
[Wherein X represents halogen. R f represents a linear or branched perfluoroalkyl group having 1 to 6 carbon atoms. ]
A perfluoroalkylsulfonyl halide represented by
General formula (III):
MCH 3 (III)
[Wherein M represents an alkali metal cation. ]
By reacting a mixture of alkali metal methane represented by
Formula (I):
(R f SO 2 ) 3 CM (I)
[Wherein R f and M are as defined above. ]
A tris (perfluoroalkylsulfonyl) methide salt represented by the formula:
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
As the organic solvent used in the production of the compound (I) in the present invention, an inert solvent in which (II) and (III) are soluble and does not react with the raw materials and products in the reaction step is preferable. For example, diethyl ether Ethers such as tetrahydrofuran, dioxane and the like are preferable, but not limited thereto. The above reaction can be carried out in a temperature range of −70 ° C. to 150 ° C., and most preferably, a temperature range of 30 ° C. to 100 ° C. is preferable.
[0006]
The reaction formula of the present invention is shown as follows.
3R f SO 2 X + 4MCH 3 → (R f SO 2 ) 3 CM + 3LiX + 3CH 3
[Wherein, R f is a linear or branched perfluoroalkyl group having 1 to 6 carbon atoms, preferably CF 3 , C 2 F 5 , C 3 F 7 , C 4 F 9] . X is a halogen, M is an alkali metal cation, and preferably Li + , Na + , K + . ]
The preferred CF 3, C 2 F 5, C 3 F 7, C 4 F 9 as R f, and as the M Li +, Na +, K + is preferred.
[0007]
【Example】
EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples.
Example 1 [Production of lithium tris (trifluoromethanesulfonyl) methide]
A 500 mL three-necked flask equipped with a condenser was purged with nitrogen, and then charged with 300 mL of a 1.4 M methyllithium / ether solution, and cooled to −55 ° C. on a dry ice / ethanol bath. With vigorous stirring, 53 g of trifluoromethanesulfonyl chloride was added dropwise. Thereafter, the temperature was gradually raised, and the reaction was carried out under boiling reflux for 7 hours.
After allowing to cool to room temperature, 5% hydrochloric acid was added while cooling and the mixture was sufficiently stirred. Crystallized lithium chloride and lithium hydroxide were filtered off.
The filtrate was extracted with ether and washed with saturated brine. The organic layer was dried over 1 hour by adding anhydrous magnesium sulfate, and then filtered under reduced pressure through a membrane filter (manufactured by Nihon Millipole) having a pore size of 0.2 μm. After the solvent was distilled off under reduced pressure, the filtrate was subjected to azeotropic dehydration by adding toluene. The obtained crystals were dried at 150 ° C. for 72 hours. As a result, 13.5 g (yield 31%) of lithium tris (trifluoromethanesulfonyl) methide: (CF 3 SO 2 ) 3 CLi was obtained.
The physical properties of the obtained substance were as follows.
Melting point: 268 ° C
13 C-NMR (CD 3 CN, δ): 123.3, 119.1
19 F-NMR (CD 3 CN, δ): −77.5 (S)
IR (kBr, cm −1 ): 3500, 1645, 1377, 1202, 1124, 983, 769, 668, 625,, 576, 506, 445, 417, 406
Example 2
A 200 mL stainless steel autoclave was purged with nitrogen, and then 100 mL of a 1.4 M methyllithium / ether solution was charged and cooled to −75 ° C. on a dry ice / ethanol bath. To this was added 20 g of trifluoromethanesulfonyl chloride. Thereafter, the temperature was gradually raised, and the reaction was carried out at 90 ° C. and 8.5 kg / cm 2 for 24 hours.
As a result of carrying out the same treatment as in Example 1, 8.1 g (yield 56%) of lithium tris (trifluoromethanesulfonyl) methide was obtained.
Example 3
As a result of carrying out the reaction under the same conditions as in Example 2 using trifluoromethanesulfonyl fluoride, lithium tris (trifluoromethanesulfonyl) methide was obtained. The yield was 42%.

Claims (1)

一般式(I):
(RfSO2)3CM …(I)
〔式中、 Rf は炭素数1から6までの直鎖または分岐状のパーフルオロアルキル基、M はアルカリ金属陽イオンを表す。〕
で表されるトリス(パーフルオロアルキルスルホニル)メチド塩の製造法であって、
一般式(II):
RfSO2X …(II)
〔式中、X はハロゲンを表す。 Rf は前記定義の通りである。〕
で示されるパーフルオロアルキルスルホニルハライドと、
一般式(III):
MCH3 …(III)
〔式中、M は前記定義の通りである。〕
で示されるアルカリ金属メタンからなる混合物を有機溶媒中で反応させることを特徴とするトリス(パーフルオロアルキルスルホニル)メチド塩の製造方法。
Formula (I):
(R f SO 2 ) 3 CM (I)
[Wherein, R f represents a linear or branched perfluoroalkyl group having 1 to 6 carbon atoms, and M represents an alkali metal cation. ]
A process for producing a tris (perfluoroalkylsulfonyl) methide salt represented by:
General formula (II):
R f SO 2 X (II)
[Wherein X represents halogen. R f is as defined above. ]
A perfluoroalkylsulfonyl halide represented by
General formula (III):
MCH 3 (III)
[Wherein M is as defined above. ]
A method for producing a tris (perfluoroalkylsulfonyl) methide salt, which comprises reacting a mixture of alkali metal methane represented by formula (1) in an organic solvent.
JP02628699A 1999-02-03 1999-02-03 Method for producing tris (perfluoroalkylsulfonyl) methide salt Expired - Lifetime JP4077103B2 (en)

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JP5186910B2 (en) 2006-12-20 2013-04-24 セントラル硝子株式会社 Method for producing tris (perfluoroalkanesulfonyl) methidoate
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