JPH0615580B2 - Polymer containing N-fluoropyridinium salt - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel polymer, more specifically, fluorine
General formula extremely useful as an agentWhere R¹, R^TwoAnd R^ThreeAre hydrogen atom and halogen atom
Represents a child or lower (halo) alkyl group; R^FourIs hydrogen
Represents a child or a methyl group; X Is a Bronsted acid
N having a molecular weight of 1000 or more containing a repeating unit represented by
-A fluoroviridinium salt-containing polymer.

Fluorine-containing compounds have recently attracted attention in the fields of medicine, agricultural chemicals and the like as those exhibiting unique physiological activities. Synthesis of such a fluorine-containing compound is often accompanied by a fluorination reaction. Several methods have been conventionally known as fluorination methods [eg, Nobuo Ishikawa, Yoshiro Kobayashi, "Compounds of Fluorine: Its Chemistry and Applications" 7
See pages 4-92, Kodansha Scientific. However, all of the conventional fluorination methods have the drawbacks such as the use of toxic, explosive and difficult to handle fluorination agents, or the need for harsh reaction conditions and low yields.
The range of its application was quite limited.

The present inventors have previously proposed an N-fluoropyridinium salt compound as a fluorinating agent for improving such drawbacks [Japanese Patent Application No. 61-125716; Tetrahedron Lett].
ers 27 , 3271 (1986); ibid., 27 , 44.
65 (1986); Bull. Chem. Soc. Jpn., 59 , 362.
5 (1986)], but since this N-fluoropyridinium salt compound has to be isolated by a recrystallization method during production, the operation is complicated and the yield is apt to decrease, and as a fluorinating agent, When used, for example As shown in (4), since a pyridinium salt in an equimolar amount with the fluorinated product (RF) is produced as a by-product, there is a drawback that a step for this separation is required, and there is room for further improvement.

Therefore, as a result of further studies to solve the above-mentioned difficulties, the present inventors have found that the above-mentioned difficulties can be overcome by fixing an N-fluoropyridinium salt as a pendant side chain to a high molecular polymer. It was found that the molecular weight of the repeating unit represented by the general formula (I) is 100.
The present invention provides a polymer containing 0 or more N-fluoropyridinium salt.

The N-fluoropyridinium salt-containing polymer of the present invention can be easily isolated by an excessive simple operation without requiring a complicated purification operation such as recrystallization in the production thereof, and , When it is used as a fluorinating agent, it has various advantages such that the by-produced pyridinium salt-containing polymer can be very easily separated from the fluorinated product by a separate operation. Very useful as a fluorinating agent.

In this specification, the term “lower” is attached with this word.
The number of carbon atoms in the atomic group or compound is 5 or less, preferably
Means 3 or less. Also, "Halogen
"Child" includes fluorine, chlorine, bromine, and iodine atoms.
It “Lower (halo) alkyl group” means one or more
Straight-chain or optionally substituted with a halogen atom
A branched chain lower alkyl group, such as methyl and ether.
Chill, n-propyl, isopropyl, n-butyl, iso
Butyl, sec-butyl, tert-butyl, n-pentyl,
Fluoromethyl, difluoromethyl, trifluoromethyl
And trichloromethyl. Furthermore, "Bren
Examples of the “stated acid” include methanesulfonic acid, butane
Sulfonic acid, benzene sulfonic acid, toluene sulfone
Acid, nitrobenzene sulfonic acid, dinitrobenzene sulphate
Fonic acid, trinitrobenzenesulfonic acid, trifluoro
Methanesulfonic acid, perfluorobutanesulfonic acid,
Lufluorooctane sulfonic acid, trichloromethane sulphate
Fonic acid, difluoromethanesulfonic acid, trifluoroe
Tansulfonic acid, fluorosulfonic acid, chlorosulfone
Acids, sulfonic acids such as monomethylsulfuric acid, sulfuric acid; perchloric acid,
Halogen such as perbromic acid, periodic acid, chloric acid, bromic acid, etc.
Acid; Nitric acid; Hydrogen chloride; HBF_Four, HPF_Four, HPF₆,
HSbF_Four, HSbF₆, HSbCl₅, HAsF₆,
HBCl_ThreeF, HAlF_Four, H_ThreeAlF₆, HSi
F₅, H_TwoSiF₆, Lewis acid and hydrogen halide
And the like. Then, "Bronsted
The “conjugated base of acid” is prepared from the above-mentioned Bronsted acid.
Roton (H Can be said to be the rest except
It

The polymers of the present invention may consist solely of one or more of the above repeating units of formula (I) or may be derived from at least one of the repeating units of formula (I) and other monomers described below. It may be a copolymer composed of at least one kind of repeating unit. In the case of the latter copolymer, the repeating unit of the formula (I) is at least 5 mol%, preferably 20 mol% or more, more preferably 30 mol% of the copolymer.
It is desirable to occupy more than mol%.

In addition, the polymer of the present invention has a
Generally, it is desirable to be solid, and the number average molecular weight is small.
At least 1000 or more, preferably 1500 to 500,000
It is preferably in the range of 2000 to 100,000.
It is profitable. Furthermore, the polymer of the present invention is stable and easy to handle.
It is desirable that it does not deteriorate.
X which is the conjugate base of stepped acid Is, as illustrated
Those with poor nuclear properties are advantageous.

The N-fluoropyridinium salt-containing polymer containing the repeating unit represented by the formula (I) of the present invention has the general formula In the formula, R ¹ , R ² , R ³ and R ⁴ have the above-mentioned meanings, and a pyridyl group-containing polymer containing a repeating unit represented by: is reacted with fluorine and the above-mentioned brensteadic acid or a metal salt thereof. It can be manufactured.

Examples of the metal salt include alkali metal salts and alkaline earth metal salts.

It is usually desirable to carry out the above reaction in a liquid medium. Examples of usable reaction mediums include acetonitrile, propionitrile, methylene chloride, chloroform, sulfolane, diethyl ether, tetrahydrofuran, and mixtures thereof. The fluorine used in the above reaction is highly reactive and reacts violently. Therefore, in order to control this appropriately, an inert gas of 99.9 to 50 is used.
It is preferable to use it after diluting it to about volume%. Examples of the inert gas that can be used for dilution include nitrogen, helium, argon, tetrafluoromethane, sulfur hexafluoride and the like. In order to carry out the reaction in good yield, it is generally convenient to use fluorine in an equimolar amount or more (preferably up to 10-fold molar amount) per 1 mol of the repeating unit of the formula (II). However, the optimum amount is appropriately determined according to the conditions such as the method of introducing fluorine into the reactant, the reaction temperature, the type of reaction medium, the reaction apparatus, etc., taking into consideration that the substrate reacts with fluorine and disappears. be able to.

On the other hand, brensteadic acid or a metal salt thereof can usually be used in an equimolar amount or an excess amount up to about 5 times the molar amount per 1 mol of the repeating unit of the above formula (II). It is preferred to use it in a molar amount.

The reaction temperature is generally within the range of -80 ° C to + 40 ° C, preferably -60 ° C to room temperature. Further, in the above reaction, hydrogen fluoride may be produced as a by-product, but if sodium trapped, for example, is coexistent as the trapping agent, the reaction yield may be improved, which may be preferable. The amount of sodium fluoride that can coexist is generally 0.5 mol or more and up to 10 mol per 1 mol of the repeating unit of the above formula (II), but it is 0.5 from the economical point of view.
The range of up to 5 moles is preferred.

The above reaction is generally carried out by dissolving or suspending a pyridyl group-containing polymer and a metal salt of Bronsted acid in a reaction medium, and blowing a diluted gas of fluorine into the mixed solution, or by using pyridyl in the reaction medium. It can be carried out by blowing a fluorine diluting gas into the group-containing polymer and then reacting it with Bronsted acid.

The reaction proceeds almost quantitatively to produce an N-fluoropyridinium salt-containing polymer in which the repeating unit represented by the formula (II) of the starting material is converted into the corresponding repeating unit represented by the formula (I). Isolation of the produced polymer from the reaction mixture is carried out by a method known per se, for example, by adding a solvent insoluble to the N-fluoropyridinium salt-containing polymer to the reaction solution and precipitating it as a solid. You can

The pyridyl group-containing polymer containing the repeating unit of the formula (II) used as a starting material in the above reaction depends on the desired N-fluoropyridinium salt-containing polymer containing the repeating unit of the formula (I). , General formula Wherein R ¹ , R ² , R ³ and R ⁴ have the meanings given above, or one or more of the vinyl pyridine compounds represented by are polymerized, or at least one of the vinyl pyridine compounds is It can be produced by copolymerizing with a copolymerizable ethylenically unsaturated monomer.

(Co) polymerization is a solution polymerization method known per se, a bulk polymerization method,
It can be carried out using an emulsion polymerization method or a suspension polymerization method. [See Chemical Society of Japan, New Experimental Chemistry Course 19, Polymer Chemistry [I], Maruzen (published in 1978)].

Vinyl pyridine compounds of formula (III) include, for example: vinyl pyridine, ie 4
-Vinylpyridine, 3-vinylpyridine and 2-vinylpyridine; 4-methyl-2-vinylpyridine, 4-methyl-3-vinylpyridine, 6-methyl-2-vinylpyridine, 5-methyl-3-vinylpyridine, 2-methyl-
4-vinylpyridine, 3-trifluoromethyl-2-vinylpyridine, 6-fluoromethyl-2-vinylpyridine, 6-difluoromethyl-2-vinylpyridine, 3,
6-dimethyl-2-vinylpyridine, 2.6-dimethyl-4-vinylpyridine, 4,6-dimethyl-2-vinylpyridine, 2,4,6-trimethyl-3-vinylpyridine, 5-ethyl-2- Vinyl pyridine, 5-ethyl-3
-Lower (halo) alkyl vinyl pyridines such as vinyl pyridine; 3-chloro-2-vinyl pyridine, 3-chloro-6-vinyl pyridine, 2-chloro-4-vinyl pyridine, 2-chloro-6-vinyl pyridine, 3-chloro-5
-Vinylpyridine, 2,5-dichloro-5-vinylpyridine, 2,6-dichloro-4-vinylpyridine, 3-fluoro-2-vinylpyridine, 5-fluoro-2-vinylpyridine, 3-fluoro-4- Vinyl pyridine, 3-
Brom-6-vinylpyridine, 3,5-difluoro-2
Halovinylpyridines such as vinylpyridine; 2-chloro-4-methyl-vinylpyridine, 2-chloro-6-methyl-4-vinylpyridine, 2,6-dichloro-4-methyl-3-vinylpyridine, etc. Lower alkyl-substituted halovinyl pyridine; isopropenyl pyridine, ie 2-
Isopropenyl pyridine, 3-isopropenyl pyridine and 4-isopropenyl pyridine; 2-methyl-6-
Lower alkyl-substituted (isopropenyl) pyridines such as (isopropenyl) pyridine, 3-methyl-6- (isopropenyl) pyridine, and 2,6-dimethyl-4- (isopropenyl) pyridine; 3-chloro-6- (iso Propenyl) pyridine, 3-fluoro-6- (isopropenyl)
Halo (isopropenyl) pyridines such as pyridine and 3-bromo-6- (isopropenyl) pyridine.

Among these, preferable examples include vinyl pyridine, methyl vinyl pyridine, dimethetyl vinyl pyridine, chlorovinyl pyridine, dichlorovinyl pyridine, (trifluoromethyl) vinyl pyridine, isopropenyl pyridine and the like.

On the other hand, the monomer copolymerizable with the vinyl pyridine compound is not particularly limited as long as it contains an ethylenically unsaturated bond, and any ethylenically unsaturated monomer can be used, The representative ones are as follows.

(A) Vinyl aromatic compounds such as stellene, α-methylstyrene, α-chlorostyrene, p-chlorostyrene, divinylbenzene and vinylnaphthalene.

(B) (Meth) acrylic acid derivative For example, (meth) acrylic acid C such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, and decyl acrylate.
₁ -C ₁₀ alkyl esters; acrylonitrile, methacrylonitrile; acrylamide, methacrylamide; acrolein, alpha-methyl acrolein like.

(C) Olefins such as ethylene, chloroethylene, dichloroethylene, fluoroethylene, chlorotrifluoroethylene, tetrafluoroethylene, tetrachloroethylene and propylene.

(D) Vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether,
Vinyl butyl ether, vinyl octyl ether, etc.

(E) Others, vinyl acetate, allyl alcohol,
Allyl methyl ether, maleic anhydride, 1 vinyl-2
-Pyrrolidine and the like.

The resulting pyridyl group-containing polymer may be of any type of alternating copolymer, random copolymer and block copolymer. Further, the vinyl pyridine compound of the formula (III) can be obtained (co) by (co) polymerization of cellulose, cellulose acetate, polyesters, polyamides, polyethers and the above ethylenically unsaturated monomer.
It may be grafted onto the polymer backbone or may be subjected to block polymerization.

The pyridyl group-containing polymer containing the repeating unit of the formula (II) is a repeating unit of the formula (I) desired in the desired N-fluoropyridinium salt-containing polymer containing the repeating unit of the formula (I). At a concentration corresponding to at least 5 mol%, preferably at least 20 mol%, more preferably 30 mol%.
It contains more than mol% of the repeating unit of formula (II). The number average molecular weight is 5 in terms of the number average molecular weight corresponding to the target polymer.
00 or more, preferably 800 to 500,000, and more preferably 1000 to 100,000.

In order to convert the N-fluoropyridinium salt-containing polymer containing the repeating unit of formula (I) into a good yield,
It is desirable that the pyridyl group-containing polymer containing the repeating unit of the formula (II) has some solubility in the reaction solvent used.

The N-fluoropyridinium salt-containing polymer provided by the present invention contains an active fluorine atom and is used as a fluorinating agent which is easy to handle, and for example, for fluorinating an aromatic compound. It is useful.

Next, the present invention will be further described with reference to examples.

Example 1 1.05 g of poly (2-vinylpyridine) [10 mmol in terms of monomer, Aldrich product, glass transition temperature (Tg) 104 ° C., number average molecular weight 3.18 × 10 ³ ],
Sodium trifluoromethanesulfonate (TfON
a) 1.72 g (10 mmol), sodium fluoride 1
g and 10 ml of anhydrous acetonitrile to a mixture of -40 ° C
While stirring at 40 ° C., add a mixed gas of F ₂ / N ₂ (1/9) to 40
The reaction solution was introduced at a flow rate of ml / min until it became a homogeneous solution. Then, after filtering with Celite, ether was added to the permeate to give a product N-fluoropyridinium salt-containing polymer as a white precipitate, which was dried and then dried N-fluoropyridinium triflate-containing polymer. Is 2.63g
Was obtained. The physical property values are shown below.

Decomposition point: 180 ° C. ¹⁹ F-NMR (CFCl ₃ internal standard in CD ₃ CN, ppm): −37.5 (NF, bs) 78.25 (CF ₃ , s) ¹ H-NMR (in CD ₃ CN, δ): 8.8 to 9.5 (Ha, m) 8.4 to 8.8 (Hc, m) 7.6 to 8.4 (Hb, Hd, m) 1.5 to 2.5 (CHCH ₂ , m) IR (Nujol, Cm ⁻¹ on NaCl plate): 3300, 3100, 1640, 1620, 1240, 1160, 1100 Examples 2 to 5 The same poly (2-vinylpyridine) as used in Example 1 was used and of Brnsted acid. Using various metal salts shown in Table 1 below under the same reaction conditions as in Example 1, various N
-A polymer containing fluoroviridinium salt was synthesized. The results are shown in Table 1 below.

Example 6 Poly (2-vinylpyridine) 1.05 g (10 mmol in terms of monomer, Aldrich commercial product, glass transition temperature (Tg) 104 ° C., number average molecular weight 3.18 × 10 ³ ],
To a mixture of 1 g NaF and 10 ml anhydrous acetonitrile,
While stirring at -40 ℃, F ₂ / N ₂ mixed gas (7/9
2) was introduced at a flow rate of 71 ml / min. F ₂ usage is 10
It was mmol. After passing the reaction solution through Celite, 10 mmol of fluorosulfonic acid was added with stirring under cooling at -40 ° C. After that, ether was added to the reaction solution to form a N-fluoropyridinium salt-containing polymer as a precipitate, and after drying, 2.46 g of an N-fluoropyridinium fluorosulfonate-containing polymer was obtained. The physical property values are shown below.

Decomposition point: 100 ° C. ¹⁹ F-NMR (CFCl ₃ internal standard in CD ₃ CN, ppm): −35.0 (FSO ₂ , s) −37.5 (NF, bs) ¹ H-NMR (in CD ₃ CN , Δ): 8.8 to 9.5 (Ha, m) 8.4 to 8.8 (Hc, m) 7.7 to 8.4 (Hb, Hd, m) 1.5 to 2.5 ( CHCH ₂ , m) Example 7 2-Vinylpyridine-styrene copolymer (commercially available from Aldrich, styrene content 30%, number average molecular weight 6.83 ×
10 ⁴ ) 0.5 g (3.33 in terms of 2-vinylpyridine)
mmol) to 100 ml of anhydrous acetonitrile,
While stirring under cooling at -40 ° C, 15.2 of a mixed gas of F ₂ / N ₂ (1: 9) was introduced (F ₂ , 68 mmol).
The reaction solution became a homogeneous solution. Then, add 7 mmol of trifluoromethanesulfonic acid (TfOH) at that temperature and add 1
Stir for 0 minutes. When ether (30 ml) was added, the product N-fluoropyridinium salt-containing polymer was precipitated as a white powder, and after drying, 1.07 g of an N-fluoropyridinium triflate-containing polymer was obtained. . The physical property values are shown below.

Decomposition point: 200 ° C. ¹⁹ F-NMR (CFCl ₃ internal standard in CD ₃ CN, ppm): −37.5 (NF, bs) 77.85 (CH ₃ , s) ¹ H-NMR (in CD ₃ CN, δ): 8.9 to 9.5 (Ha, m) 8.45 to 8.9 (Hd, m) 7.7 to 8.45 (Hb, Hc, m) 6.8 to 7.5 (phenyl) Nuclear hydrogen, m) IR (Nujol on NaCl plate, cm ⁻¹ ): 3300, 1620, 1010, 720 Reference Example 1 54 mg (0.55 mmol) of phenol, 0.40 N-fluoropyridinium salt-containing polymer obtained in Example 7
g (0.63 mmo as N-fluoropyridinium salt)
A mixture of 1) and 2 ml of anhydrous 1,1,2-trichloroethane was stirred under a nitrogen atmosphere at 100 ° C. for 14 hours. After the reaction, the pyridinium hydrogen salt polymer present as a white precipitate was removed by filtration, and the excess liquid was quantified by gas chromatography. The conversion rate of phenol was 52%. , And 2,4-difluorophenol conversion yields were 60%, 26%, and 3%, respectively.

Claims (1)

[Claims] 1. A general formulaWhere R¹, R^TwoAnd R^ThreeAre hydrogen atom and halogen atom
Represents a child or lower (halo) alkyl group; R^FourIs hydrogen
Represents a child or a methyl group; X Is a blend of
N having a molecular weight of 1000 or more containing a repeating unit represented by
-Fluorobiridinium salt-containing polymers.