JP2862293B2 - Linear poly (2,2'-bipyridine-5,5'-diyl) polymer, method for producing and using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention uses a unit in which 2,2′-bipyridine is bonded at the 5,5′-position as a repeating unit and has excellent heat resistance and solubility. Linear poly (2,2'-bipyridine-5,5'-diyl) polymer having, converted to a conductive substance by doping, and serving as a ligand for a metal element, and its production and use It is about.

[Problems and Solutions for Solving the Problems of the Prior Art] Aromatic rings are continuously bonded to form a continuous π along the main chain.
A poly conjugated system (Ali - Len) (e.g., poly (p- phenylene), poly (2,5-thienylene), etc.) has generally good heat resistance, the electron acceptor (iodine, such as AsF ₅ ) And an adduct with an electron donor (such as an alkali metal) have excellent properties such as being conductive and being usable as an active material for primary batteries and secondary batteries (for example, Magazine "Polymer", 34, 848 (198
5), 38, 1080 pages (1989)).

On the other hand, such a π-conjugated conductive aromatic polymer compound is considered to have a relatively rigid structure due to the aromatic ring in the main chain. When such a main chain has π-conjugated conductivity and a polymer having a rigid structure acts on a metal element as a ligand, an unprecedented electronic state (for example, when the ligand is a semiconductor) It is expected that a metal complex having an active band structure and a coordination state (for example, a coordination unsaturated structure is likely to be formed due to the rigidity of the ligand) will be obtained.

Up to now, some π-conjugated conductive aromatic polymers have been
Examples of interaction with ²⁺ ions were known,
Polymers in which the main chain structure of a π-conjugated conductive aromatic polymer is composed of structural units exhibiting a strong coordination force such as a chelate ligand (eg, 2,2′-bipyridine, diphosphine, etc.) structure Π with large coordination force to metal elements
There is no synthesis example of a conjugated conductive aromatic polymer. For example, Poly (2,5-pyridinediyl) having a repeating unit of 2,5-pyridinediyl group represented by the following formula (Japanese Patent Application No. 63-236) is considered to be mainly composed of head-to-tail bonds. The ability to coordinate to Fe2 ⁺ ions and the like (although some are thought to have head-to-head or tail-to-tail bonds corresponding to 2,2'-bipyridine) is generally poor.

In order to overcome such a problem, the present invention provides the following formula corresponding to 2,2'-bipyridine ligand, which is one of typical chelating ligands. A new polymer ligand, which is a π-conjugated conductive aromatic polymer compound having a 2,2'-bipyridine-5,5'-diyl group as a repeating unit represented by It is expanded. The polymer of the present invention exhibits properties not only as a ligand but also as a heat-resistant polymer and a conductive polymer.

[Principle of production method] Poly (2,2'-bipyridine-5,5'-diyl) of the present invention
The following formula is used to manufacture Or (X represents a halogen in both formulas). A method is considered in which the compound represented by the formula (1) is dehalogenated with a metal or a metal compound in a reduced state. 5,5'-diyl) for the first time. In the polymer obtained by dehalogenation of the compound B represented by the latter formula of the above two formulas, the terminal is not a unit corresponding to 2,2'-bipyridine, but the portion excluding the terminal is 2,2. 2 ′
The following formula corresponding to bipyridine: It consists of a repeating unit represented by

A method in which a dihalogenated organic compound is polymerized by dehalogenation with a metal such as magnesium or zinc in the presence of a catalyst (Japanese Patent 951386, 1200926, 1258016, Japanese Patent Application No. 60-075869) or a method of dehalogenating and polymerizing with a nickel compound in a reduced state such as zero-valent nickel (Japanese Patent Application Nos. 63-236 and 63-236)
-159635) X-R-X + NiLm → R n + NiX 2 Lm '(3) (L denotes a neutral ligand) has, poly (2 by applying these methods compounds A, the compound B, 2'-bipyridine-5,5'-diyl) is obtained. In the polymerization reactions of Examples 2 and 3 below,
The polymerization reaction was carried out under an inert gas such as nitrogen or argon using a solvent which had been replaced with an inert gas under an inert gas.

[Example 1] Using 2,5-dibromopyridine as a raw material, a literature (JC
hem. Soc., Perkin Trans. I, 1839 (1984) and Phosphor.
5,5'-Dibromo-2,2'-bipyridine was synthesized by a method according to US and Sulfur, vol. 34, p. 123 (1987). That is, 17.7 g (74.7 mmol) of 2,5-dibromopyridine and 52.3 g (112 mmol) of CH ₃ SNa were reacted under reflux in 50 ml of benzene in the presence of 0.68 g of tetrabutylammonium bromide Bu ₄ NBr. The resulting product was distilled under reduced pressure to obtain 13.9 g (yield 91%) of 2-methylthio-
5-bromopyridine (following formula) I got

This 2-methylthio-5-bromopyridine (13.8 g)
Was oxidized with 9.21 g of 30% aqueous hydrogen peroxide to give 6.2 g of the corresponding sulfoxide (methyl (5-bromo-2-pyridyl) sulfoxide). In addition, this sulfoxide (650m
g, 3.72 mmol) was reacted with ethylmagnesium bromide in ether and worked up to give 5,5'-dibromo-2,2'-bipyridine (350 mg). The product was confirmed by elemental analysis, NMR method, IR method and the like.

[Example 2] 5,5'-Dibromo-2,2'-bipyridine (630 mg, 2.0 mmol), bis (1,5-) obtained by the method described in Example 1
Cyclooctadiene) nickel (abbreviated as Ni (cod) ₂ )
(1.1 g, 4.0 mmol), 2,2'-bipyridine (620 mg, 4.0 mmol
The three compounds of l) were added to 18 ml of N, N-dimethylformamide and reacted at 60 ° C. for 20 hours and further at 80 to 90 ° C. for 6 hours to obtain a yellow polymer compound as a precipitate.

This precipitate was separated, and methanol, hydrochloric acid-methanol, pH9 ethylenediaminetetraacetic acid (abbreviated as EDTA) aqueous solution, pH3 EDTA aqueous solution, ammonia water, water, methanol,
After sufficiently washing with tetrahydrofuran, hexane, and ether, vacuum drying was performed to obtain the desired poly (2,2'-bipyridine-5,5'-diyl) (258 mg).

This polymer was soluble in formic acid, and the molecular weight of this polymer in a formic acid solution was measured by light scattering method. As a result, it was found that this polymer had an average molecular weight of 3200. This molecular weight is about 21 units of 2,2'-bipyringin-5,5'-diyl group.
This corresponds to a polymer that is continuously bonded. The results of the elemental analysis almost agreed with those calculated assuming that this polymer had a structure as the above-mentioned poly (2,2'-bipyridine-5,5'-diyl).

FIG. 1 shows the infrared absorption spectrum (KBr tablet method) of the above yellow polymer (poly (2,2'-bipyridine-5,5'-diyl)) in the region of 400 to 1700 cm ^-1 . Formic acid solution of poly obtained in this Example (2,2'-bipyridine-5,5'-diyl) is in terms of per 2,2'-bipyridine units 376nm 10 ⁴ l mol ^-1 cm ^-1 It exhibits absorption characteristic of π-π ^* absorption with extinction coefficient of the order, and its formic acid solution is ¹³ C-N
In the MR spectrum, the characteristic absorption (plural) of the aromatic ring carbon was shown at 125 to 149 ppm.

The poly (2,2'-bipyridine-5,5'-diyl) obtained in this example was found to have d = 5,277 by powder X-ray diffraction.
Å and d = 7.561 ° showed a strong diffraction peak.

Example 3 584 mg (1.86 mmol) of 5,5'-dibromo-2,2'-bipyridine, 639 mg (2.32 mmol) of Ni (cod) ₂ , 348 mg (2.23 mm)
ol) 2,2'-bipyridine was reacted in 12 cm ³ of N, N-dimethylformamide at 70 ° C. for 12 hours, except that poly (2,2'-bipyridine-5,5'- Diyl) was synthesized. Light scattering in a formic acid solution showed that the polymer obtained in this example had an average molecular weight of 1400. In addition, the formic acid solution of the polymer of this example had a π-
It showed absorption characteristic of π ^* absorption.

[Example 4] The thermostability of the polymer (poly (2,2'-bipyridine-5,5'-diyl)) obtained in Example 3 was diffracted by thermogravimetric analysis. Showed no weight loss up to 270 ° C. and had high thermal stability.

[Example 5] The polymer (powder obtained in Example 3 [sodium Naphthalide as an electron donor] ^{_{(Na + [C 10 H 8}} -] dipped in tetrahydrofuran) gave a powder of red black The red-black powder was separated, dried in vacuo, and then pressed under a pressure of about 200 kg / cm ² to obtain a tablet sample.The conductivity of the tablet sample was measured, and 1.6 × 10 ⁻¹ Scm ⁻ A conductivity of ¹ (Siemens per centimeter) was obtained, the above operation was carried out by inert gasification, the yellow polymer obtained in Examples 2 and 3 itself was an insulator.

Example 6 The formic acid solution of the polymer obtained in Example 3 was spread on a glass plate, and formic acid was evaporated at room temperature, whereby a yellow film having a relatively large strength was obtained in a glass plate shape.

Example 7 A solution of the polymer obtained in Example 3 in an amount of formic acid and an aqueous solution of iron (II) sulfate were prepared. Contained in the polymer in the formic acid solution
Unit corresponding to 2,2'-bipyridine (the following formula) The molar number of (unit A) and the molar number of Fe ^{2+ in} the aqueous solution were approximately 3: 1. When these two solutions were mixed, a red precipitate was formed. This red color indicates the formation of a complex similar to the complex containing tris (2,2'-bipyridine) iron (II) ion, indicating that the polymer of the present invention functions as a polymer ligand. . The red precipitate clearly had a different color than the polymer-only precipitate. Also,
A similar experiment was conducted using poly (2,5-pyridinediyl) shown on page 5 of this specification (the number of moles of 2,5-pyridinezindiyl group unit and the moles of FeSO _{4 in} the polymer). Number
6: 1), in which case only the formation of a precipitate characteristic of yellow poly (2,5-pyrididiyl) was observed, with no clear evidence of complex formation.

Example 8 A formic acid solution of the polymer obtained in Example 3 and an ethanol solution of ruthenium chloride were prepared. The mole number of the unit A contained in the polymer in the formic acid solution and the mole number of Ru ion in the ethanol solution were approximately 3: 1. When the two solutions were mixed, a black-brown precipitate was formed, indicating that a complex formation reaction had occurred. However, the black brown color of this complex is different from the red color characteristic of the complex containing tris (2,2'-bipyridine) ruthenium (II) ion, and the black brown complex obtained in this example has the main chain. It indicates that it has a unique electronic state or a coordinatively unsaturated state due to its π-conjugated system, conductivity, and rigidity.

[Effects of the present invention] According to the present invention, useful poly (2,2'-bipyridine-5) which has high heat resistance, is soluble in a solvent, has conductivity, and can be used as a polymer ligand. , 5'-diyl).

[Brief description of the drawings]

FIG. 1 shows the infrared absorption spectrum of poly (2,2'-bipyridine-5,5'-diyl).

Continued on the front page (58) Fields investigated (Int. Cl. ⁶ , DB name) C08G 61/00-61/12 CA (STN) REGISTRY (STN)

Claims (6)

(57) [Claims] 1. The following equation A linear poly (2,2'-bipyridine-5,5'-diyl) polymer comprising a 2,2'-bipyridine-5,5'-diyl group as a repeating unit. 2. The following equation Or (In the above two formulas, X represents a halogen) 5,5′-dihalogenated-2,2′-bipyridine or 6,6′-dihalogenated-3,3′-bipyridine is reduced A method for producing the polymer according to claim 1, wherein the polymer is dehalogenated in the presence of a metal compound or a metal in a state. 3. A method for obtaining a film or a filamentous substance of the polymer using a solution obtained by dissolving the polymer according to claim 1 in formic acid. 4. A conductive substance obtained by adding an electron donor to the polymer according to claim 1. 5. A conductive substance obtained by reducing the polymer according to claim 1. 6. Use of the polymer according to claim 1 as a ligand for a metal element.