JP2913325B2 - Aniline-based polymer, optical isomer splitting membrane using the same, and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a novel aniline-based polymer and a divided film using the polymer, that is, an optical isomer can be electrochemically separated. It is possible to selectively take in only one of the optical isomers by applying a potential to the membrane in a split membrane, more specifically, a mixed solution of d-form and l-form or S-form and R-form. And a method for producing the same.

[Conventional technology]

Conventional aniline polymers have a halogen, alkyl, alkoxy, or sulfonic acid group on the benzene ring, or have an alkyl or phenyl group at the N-position. It is not limited to dielectrics, electrochromic devices, electrodes of primary or secondary batteries, etc., and none is used for separating organic compounds. On the other hand, in the synthesis of organic compounds having various asymmetric atoms, many attempts have been made to separate the resulting optical isomers or to selectively synthesize only one of the optical isomers. In the former, a method using an optical resolving agent using an optically active substance, a method using liquid chromatography using a column using an optically active polymer as a carrier, and a separation method using a permeable membrane having asymmetric selective permeability are well known. ing. However, these methods have problems such as difficult handling, time-consuming separation, and high cost.
On the other hand, for the latter, a method using a so-called asymmetric synthesis catalyst using an enzyme or a compound having an asymmetric atom as a catalyst is well known. However, such a catalyst has problems that it is expensive and that handling such as recovery after the reaction is difficult.

[Problems to be Solved by the Invention] The present invention solves such problems and provides a novel aniline-based polymer and a separation membrane capable of electrochemically performing optical resolution using the same. It is intended to provide a manufacturing method thereof.

[Means for Solving the Problem] As a result of intensive studies to solve the above problems, the present inventor has used an aniline-based polymer film in which a substituent having an asymmetric carbon at the N-position of aniline has been introduced. As a result, they found that electrochemical optical resolution was possible, and completed the present invention.

The invention of claim 1 of the present invention relates to the following general formula (I) (Where A, B, and D are each bonded to an asymmetric carbon C ^* , and A, B, and D are not the same as each other, and are hydrogen, hydroxyl, alkyl, phenyl-substituted alkyl, alkenyl, and aryl. Or an alkoxy group, m is an integer of 1 to 30, n is 8
An aniline polymer represented by the following formula:

The invention of claim 2 provides the following general formula (I) (Wherein A, B, D and m, n have the above-mentioned meanings).

The invention of claim 3 is a compound of the following general formula (II) at the N-position of aniline: (Wherein A, B, and D are each bonded to an asymmetric carbon C ^* , and A, B, and D are not the same as each other, hydrogen, hydroxyl, alkyl, phenyl-substituted alkyl, alkenyl, aryl A group or an alkoxy group, and m represents an integer of 1 to 30)
An aniline derivative having a substituent represented by formula (1) is formed on an electrode by electrochemical oxidation polymerization of an aniline-based polymer, followed by ammonia treatment or electrochemical dedoping to produce an optical isomer-separated membrane. Is the way.

The invention of claim 4 is a compound of the following general formula (II) at the N-position of aniline: Wherein A, B, D and m have the above-mentioned meanings. An aniline derivative having a substituent represented by the following formula is oxidized and polymerized with an oxidizing agent to produce an aniline-based polymer. This is a method for producing an optical isomer-separated film obtained by subjecting an ammonia treatment or electrochemical dedoping to pink and then forming the film.

The aniline-based polymer of the present invention is obtained by oxidative polymerization of an aniline derivative having an asymmetric carbon as a substituent. As the method of oxidative polymerization, electrochemical oxidation or a method using an oxidizing agent can be used. Hereinafter, a method for synthesizing the novel aniline polymer of the present invention will be described.

The monomer constituting the aniline polymer of the present invention is N
It is an aniline derivative having a substituent containing an asymmetric carbon at the position, and can be synthesized by the following method.

That is, the general formula (III) (Where A, B, and D have the above-mentioned meanings), and a carboxylic acid having an asymmetric carbon represented by the formula: X (CH ₂ ) _m —OH (X is Halogen, m
Is an integer of 1 to 30) to obtain an ester represented by the general formula (IV).

Next, the ester of the above general formula (IV) is reacted with aniline in an ether solvent to obtain an aniline derivative having a substituent containing an asymmetric carbon at the N-position as shown in the above general formula (II). Can be.

A, B, D and m in the general formula (II) have the above-mentioned meanings, and A, B and D specifically include, for example, groups shown below. It is necessary to be.

That is, hydrogen; hydroxyl group; methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec.
Alkyl groups such as -butyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-dodecyl, n-hexadecyl, n-eicosyl and n-docosyl Alkenyl groups such as vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl and the like; phenyl-substituted alkyl groups such as benzyl and phenethyl; phenyl, tolyl, xylenyl, anisyl,
Aryl groups such as naphthyl, anthryl, phenanthryl and pyrenyl; and alkoxy groups such as methoxy, ethoxy and propoxy are applied to the aniline derivative referred to in the present invention.

Examples of the carboxylic acid having an asymmetric carbon represented by the general formula (III) include (S)-(+)-mandelic acid, (R)-(-)-mandelic acid, and (R)-(- )-
α-methoxyphenylacetic acid, (S)-(+)-α-methoxyphenylacetic acid, (R)-(−)-2-phenylpropionic acid, (S)-(+)-2-phenylpropionic acid, D- Lactic acid, L-lactic acid, and the like.

Examples of the halogenated alcohol used in the esterification reaction with the carboxylic acid include chloromethanol, bromomethanol, 2-chloroethanol, 2-bromoethanol, 3-chloropropanol, 3-bromopropanol, and 4-chloro-1. -Butanol, 4-bromo-1-butanol, 10-chloro-1-decane alcohol, 10-bromo-1-decane alcohol, 20-chloro-
1-aceanol, 20-bromo-1-aceanol, 30
-Chloro-1-triacontanol, 30-bromo-1-
Triacontanol and the like.

The novel aniline polymer represented by the general formula (I) of the present invention can be obtained by oxidatively polymerizing the aniline derivative shown above as follows.

Electrochemical oxidative polymerization, which is one of the oxidative polymerization methods of the present invention, is anodization, and usually, the voltage is in the range of 100 mV to 50 V,
For example, a constant potential electrolysis method, a constant current method, a constant voltage method, etc.
Electropolymerization method) is used. The polymerization can be carried out in water, an organic solvent or a mixture thereof. The supporting electrolyte coexisting with the monomer includes hydrochloric acid, sulfuric acid, borofluoric acid, perchloric acid, nitric acid, benzenesulfonic acid,
Protonic acid such as p-toluenesulfonic acid is used. Alternatively, a salt of the protonic acid may be used.

The pH of the electrolyte is preferably 3 or less. Above pH 3, the polymer yield is low. Further, it is preferable that dissolved oxygen does not exist in the electrolytic solution, and the electrolytic reaction is also preferably performed under an inert gas such as nitrogen or argon. This is because the dissolved oxygen in the electrolytic solution suppresses the progress of the polymerization reaction and makes it difficult to obtain a polymer having a high molecular weight. The electrode used for the electropolymerization is not particularly limited. For example, metals such as platinum, gold, copper, nickel and chromium, carbon electrodes such as glassy carbon and graphite, metal oxides such as nesa glass and ITO glass (indium oxide) It is possible to use various electrodes such as a composite electrode.

As a method using an oxidizing agent, an acidic aqueous solution of a monomer or a solution of an organic solvent is prepared, and the oxidizing agent is added to the solution.
The polymerization is carried out for a period of time up to 100 hours. Examples of the oxidizing agent include ammonium persulfate, persulfates such as potassium persulfate and sodium persulfate; permanganates such as potassium permanganate; metaperiodates such as sodium metaperiodate; hydrogen peroxide; Ferric iron or the like is used. The polymerization temperature is not particularly limited, but is preferably from -20 ° C to 100 ° C.

As a method for obtaining a polymer, electrochemical oxidative polymerization is more advantageous for use in the present invention since the polymer is formed on the electrode as a film.

In both the electrochemical oxidation polymerization and the oxidation polymerization using an oxidizing agent, the obtained aniline-based polymer according to the present invention is doped with the protonic acid or the oxidizing agent used in the reaction. In the present invention, these dopants inhibit the incorporation of the optical isomer into the film.Therefore, when the aniline-based polymer according to the present invention is used as an optical isomer-separated film, it may be immersed in aqueous ammonia or exposed to ammonia gas. For ammonia treatment or saturated calomel electrode,
It is necessary to remove the dopant by a method such as applying an electric potential of 0 V or less to the aniline-based polymer and undoping it electrochemically. These methods of ammonia treatment and electrochemical undoping may be used alone or in combination.

When the aniline-based polymer of the present invention thus obtained is synthesized by electrochemical oxidation polymerization, it is formed on the electrode and can be used as it is in the present invention as an optical isomer separation film, but it is separated from the electrode. It is also possible to use the film alone. When polymerization is carried out using an oxidizing agent, a film is formed on an electrode used for electrochemical oxidation polymerization by a method such as casting, or a film is formed on an appropriate substrate and used alone.

The above-mentioned platinum,
When a potential of 0.1 to 10 V is applied to a saturated calomel electrode or a silver / silver chloride electrode in a mixed solution of optical isomers with an electrode used for electropolymerization of gold, copper or the like as a counter electrode, the asymmetric carbon of the aniline substituent is removed. Only optical isomers of the same symmetry are incorporated into the film, and optical isomers of different symmetry remain in solution. When a potential opposite to that at the time of incorporation is applied to a film in which optical isomers having the same symmetry are incorporated, the incorporated isomer is released. Thus, only the optical isomer having the same symmetry can be easily separated from the mixed solution of the optical isomers.

<Examples> Example 1. (S)-(+)-Mandelic acid is reacted with 2-bromoethanol to form an ester, and then the ester is reacted with aniline to convert (S) -anilinoethyl mandelic monomer. The following aniline derivatives were synthesized. The electrolytic solution was an aqueous solution of this monomer 0.1 mol / hydrochloric acid 2 mol / and platinum was used as an electrode, and electrolytic polymerization was performed at a potential of 0.8 V with respect to a saturated calomel electrode under a nitrogen atmosphere for 2 hours. An aniline polymer of the present invention having a green repeating unit represented by the following formula (V) was formed on the platinum electrode on the anode side. Intrinsic viscosity of the obtained polymer (concentration at 30 ° C., 0.5 g / dl N-methyl-
2-hirolidone solution) was 0.26 dl / g. This is firstly de-doped at a potential of -0.5 V for 20 minutes, and further 1 mol /
For 3 hours to complete de-doping, thereby producing an optical isomer-separated film according to the present invention.

On a platinum electrode covered with a film of this undoped polymer,
(S)-(+)-and (R)-(-)-Camphor-10
A potential of 0.5 V is applied to the saturated calomel electrode in an aqueous solution containing 0.1 mol / ammonium sulfonate for 10 minutes to apply (S)-(+)-camphor-10 to the polymer film on the platinum electrode.
Ammonium sulfonate was taken up. This platinum electrode was transferred to an aqueous solution using ammonium chloride as a supporting electrolyte, and a potential of -0.5 V was applied to the saturated calomel electrode over 10 minutes to remove (S)-(+)-camphor-10-sulfonic acid. Doped. The specific rotation of the solution after undoping is [α] ²⁰ _D
At + 21 °, it was confirmed that only the (S)-(+)-isomer was separated, and the optical isomer was easily separated.

Example 2 2 g of a monomer composed of the aniline derivative used in Example 1
Was dissolved in chloroform, and 2 g of ferric chloride was used as an oxidizing agent.
The mixture was further stirred at room temperature for 12 hours. When this solution was poured into methanol, 2 g of a dark green aniline-based polymer of the present invention was obtained. This was stirred for 4 hours in a 1 mol / aqueous ammonia solution to perform a de-doping treatment. The undoped polymer was dissolved in chloroform, and an optical isomer splitting film according to the present invention was formed on a platinum electrode by a casting method.

The platinum electrode covered with this polymer film has (S)-
In an aqueous solution containing 0.1 mol / min of (+)-and (R)-(-)-camphor-10-sulfonate, a potential of 0.5 V was applied to the saturated calomel electrode for 30 minutes with respect to the saturated calomel electrode. (S)-(+)-Camphor-10-ammonium sulfonate was incorporated into the combined membrane. This platinum electrode was transferred to an aqueous solution using ammonium chloride as a supporting electrolyte, and a potential of -0.5 V was applied to the saturated calomel electrode for 30 minutes to remove (S)-(+)-camphor-10-sulfonic acid. Doped. The specific rotation of the solution after undoping is [α] ²⁰ _D = + 2
At 1 °, it was confirmed that only the (S)-(+) form was separated. Therefore, optical isomers could be easily separated.

Example 3 An aniline was reacted with a reaction product of (S)-(+)-mandelic acid and 2-bromopropanol to synthesize an aniline derivative comprising an (S) -mandelic acid anilinopropyl monomer. The electrolyte is 0.1 mol of this monomer, 2 mol of hydrochloric acid
Using a platinum electrode as the electrode, electrolytic polymerization was performed at a potential of 0.8 V with respect to the saturated calomel electrode for 2 hours under a nitrogen atmosphere. A green aniline-based polymer according to the present invention was formed on the platinum electrode on the anode side. The intrinsic viscosity (having the above-mentioned meaning) of the obtained polymer was 0.23 dl / g. This is firstly dedoped at a potential of -0.5 V for 20 minutes,
It was immersed in 1 mol / aqueous ammonia for 3 hours to complete the undoping, and an optical isomer splitting film according to the present invention was produced.

On a platinum electrode covered with a film of this undoped polymer,
(S)-(+)-and (R)-(-)-Camphor-10
-In an aqueous solution containing 0.1 mol / ammonium sulfonate, a potential of 0.5 V was applied to the saturated calomel electrode for 30 minutes to apply (S)-(+)-camphor-10 to the polymer film on the platinum electrode.
Ammonium sulfonate was taken up. The platinum electrode was transferred to an aqueous solution using ammonium chloride as a supporting electrolyte, and a potential of -0.5 V was applied to the saturated calomel electrode over 30 minutes to remove (S)-(+)-camphor-10-sulfonic acid. Doped. The specific rotation of the solution was [α] ²⁰ _D = + 21 °, confirming that only the (S)-(+) form was separated.
From this, the separation of the optical isomers was very easily performed.

Example 4. The aniline-based polymer of the present invention used in Example 3 was peeled off from a platinum electrode, dissolved in chloroform, and cast on a glass substrate to form a thin film. After peeling from the substrate, a platinum electrode was attached to the thin film again, and the same as in Example 3 (S)-(+)-
And (R)-(-)-Camphor-10-ammonium-10-sulfonate in an aqueous solution containing 0.1 mol / each, applying a potential of 0.5 V to the saturated calomel electrode for 30 minutes to form a thin film on the electrode (S).
-(+)-Camphor-10-ammonium sulfonate was incorporated. The platinum electrode was transferred to an aqueous solution using ammonium chloride as a supporting electrolyte, and the saturated calomel electrode was moved to −0.2.
The (S)-(+)-camphor-10-sulfonic acid taken in at a potential of 5 V for 30 minutes was dedoped. The specific rotation of the solution after undoping is [α] ²⁰ _D = + 21 ° and (S) − (+)
It was confirmed that only the isomer was separated, and the separation of the optical isomer was easy.

Example 5. An aniline was reacted with a reaction product of (R)-(-)-2-phenylpropionic acid and 2-bromoethanol to obtain an aniline derivative composed of an anilinoethyl (R) -2-phenylpropionate monomer. Synthesized. The electrolytic solution was an aqueous solution of this monomer 0.1 mol / hydrochloric acid 2 mol / and platinum was used as an electrode, and electropolymerization was performed at a potential of 0.8 V with respect to a saturated calomel electrode under a nitrogen atmosphere for 4 hours. An aniline-based polymer of the present invention having a green repeating unit represented by the following formula (VI) was formed on the platinum electrode on the anode side. The intrinsic viscosity (having the above-mentioned meaning) of the obtained polymer was 0.25 dl / g. This was firstly dedoped at a potential of -0.5 V for 20 minutes, and further immersed in 1 mol / aqueous ammonia for 3 hours to complete the undoping, thereby producing an optical isomer splitting film according to the present invention.

On a platinum electrode covered with a film of this undoped polymer,
(S)-(+)-and (R)-(-)-Camphor-10
A potential of 0.5 V is applied to the saturated calomel electrode in an aqueous solution containing 0.1 mol / ammonium sulfonate for 10 minutes to apply (R)-(-)-camphor-10 to the polymer film on the platinum electrode.
Ammonium sulfonate was taken up. The platinum electrode was transferred to an aqueous solution using ammonium chloride as a supporting electrolyte, and a potential of -0.5 V was applied to the saturated calomel electrode over 10 minutes to remove (R)-(-)-camphor-10-sulfonic acid. Doped. The specific rotation of the solution after undoping is [α] ²⁰ _D
At −21 °, it was confirmed that only the (R)-(−)-isomer was separated, and the optical isomer was easily separated.

〔The invention's effect〕

When the film made of the aniline-based polymer according to the present invention is used as an optical isomer separation film, it is a film that can electrochemically separate the optical isomers, so it is easy to handle and the optical isomer can be easily separated. Can be very useful.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C25B 3/02 C25B 3/02

Claims (4)

(57) [Claims] 1. The following general formula (1) (Where A, B, and D are each bonded to an asymmetric carbon C ^* , and A, B, and D are not the same group as each other; hydrogen, hydroxyl, alkyl, phenyl-substituted alkyl, alkenyl, and aryl. Or an alkoxy group, m represents an integer of 1 to 30, and n represents an integer of 8 to 500). 2. The following general formula (I) (Where A, B, and D are each bonded to an asymmetric carbon C ^* , and A, B, and D are not the same as each other, hydrogen, hydroxyl, alkyl, phenyl-substituted alkyl, alkenyl, and aryl. Or an alkoxy group, m is an integer of 1 to 30, and n is an integer of 8 to 500). 3. The compound of the following general formula (II) at the N-position of aniline: (Where A, B, and D are each bonded to an asymmetric carbon C ^* , and A, B, and D are not the same as each other, hydrogen, hydroxyl, alkyl, phenyl-substituted alkyl, alkenyl, and aryl. Or an alkoxy group, and m represents an integer of 1 to 30). An aniline derivative having a substituent represented by the formula (1) is electrochemically oxidized and polymerized to form an aniline-based polymer on an electrode. A method for producing an optical isomer separation film, characterized by chemically dedoping. 4. The compound of the following general formula (II) at the N-position of aniline: (Where A, B, and D are each bonded to an asymmetric carbon C ^* , and A, B, and D are not the same as each other, hydrogen, hydroxyl, alkyl, phenyl-substituted alkyl, alkenyl, and aryl. Or an alkoxy group, and m represents an integer of 1 to 30). An aniline derivative having a substituent represented by the formula (1) is oxidatively polymerized with an oxidizing agent to produce an aniline polymer, and the obtained polymer is treated with ammonia. Alternatively, a method for producing an optical isomer separation film, which comprises electrochemically dedoping.