JPH075535B2 - New manufacturing method of organic conductive complex - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Use of the Invention] The present invention relates to TCNQ (7,7,8,8-
The present invention relates to a new method for producing a tetracyanoquinodimethane) complex.

[Background of the Invention]

The TCNQ complex is a charge transfer complex compound known as an organic semiconductor, and its constituent component TCNQ easily accepts an electron, and forms an extremely stable radical salt with a cation.
It exhibits high conductivity due to its unique structural feature that TCNQ itself stacks.

The TCNQ complex has the advantage that it can utilize the characteristic properties of organic compounds as a metal, such as light weight, electrical conductivity anisotropy, meltability, film formability, and ease of processing and molding. , High-performance conductive molecular film, nonlinear optical material,
There are great expectations for its application in applications to antistatic agents, molecular devices, biological devices, the design of highly ordered molecular assemblies with electronic functions, or in various organic semiconductor fields such as solid electrolytes for electrolytic capacitors and batteries. Is a compound.

Regarding the TCNQ complex, a large number of nitrogen-containing heterocyclic compound cation TCNQ complexes have been synthesized so far, but they are all produced by either of the following two methods. That is, one of them is a method of utilizing the reducibility of iodo ion I ⁻ to react a nitrogen-containing heterocyclic compound cation iodide D ⁺ I ⁻ with neutral TCNQ in the presence of a suitable solvent such as acetonitrile or dichloromethane. , The other is to react the same cation D ⁺ halide and TCNQ Li salt in a solvent such as methanol. Is obtained in a solvent such as acetonitrile.
This is a method of doping TCNQ.

However, these conventional methods known per se can only obtain the TCNQ complex having the most stable structure in the solvent used, and therefore, the cation (D ⁺ ) And TCNQ anion radical And the neutral TCNQ (TCNQ °) composition ratio is determined by the nitrogen-containing heterocyclic compound used and the solvent used, and TCNQ complexes with various composition ratios can be produced depending on the purpose. It was impossible at all.

[Object of the Invention]

The present invention has been made in view of the above circumstances, and includes a nitrogen-containing heterocyclic compound (D ⁺ ) and a TCNQ anion radical. TCNQ complex consisting of and TCNQ (TCNQ °) · ^(TCNQ.) Variously changed and the value of m At a _m, the TCNQ complexes having various complex composition ratio can be arbitrarily prepared, and an object thereof is to provide a novel process for the preparation of TCNQ complexes.

[Structure of Invention]

The present invention comprises the following general formula [I] characterized in that a mixture consisting of any combination described in (i) to (v) below is subjected to a melting reaction by heating. [Wherein [D ₁ ⁺ ], [D ₂ ⁺ ] and [D ₃ ⁺ ] are each independently the following general formulas [II] to [XVIII] (Wherein R ¹ , R ² , R ³ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹² ,
R ¹³ , R ¹⁶ , R ¹⁷ , R ¹⁸ , R ¹⁹ , R ²¹ , R ²² , R ²³ , and R ²⁴ each independently represent an alkyl group or an aralkyl group, and R ⁴ and R ⁵
Are each independently a hydrogen atom or a methyl group, and R ¹¹ , R
¹⁴ , R ¹⁵ and R ²⁰ each independently represent a hydrogen atom or an alkyl group. Represents an N-substituted nitrogen-containing heterocyclic compound cation selected from Represents a 7,7,8,8-tetracyanoquinodimethane anion radical, and [R-TCNQ °] is represented by the following general formula [XIX] (However, R ²⁵ and R ²⁶ each independently represent a hydrogen atom or a lower alkyl group.), A neutral 2-alkyl-, 2,5-dialkyl- or unsubstituted 7,7,8, 8-tetracyanoquinodimethane, where p, q and r are each independently p
+ Q + r = 1 represents a value satisfying 1 and m represents a value in the range of 0 <m ≦ 3.5. ] The manufacturing method of the organic electroconductive complex shown by these.

That is, the present inventors have found that the nitrogen-containing heterocyclic compound (D ₁ ⁺ , D ₂ ⁺ ,
D ₃ ⁺ ) and TCNQ anion radical TCNQ complex consisting of and a neutral, substituted or unsubstituted TCNQ (R-TCNQ °) (However, in the case of p + q + r = 1, 0 <m ≦ 3.5), TCNQ complexes having various complex constituent ratios with various values of m, which cannot be obtained by the conventional method, can be arbitrarily produced according to the purpose. As a result of earnest research on the method, the above (i) to (v)
The inventors have found that the object can be achieved by subjecting a mixture of the combinations as described in 1 above to a heat-melting reaction in the absence of a solvent, and completed the present invention.

The above general formula [XIX] used in the present invention Examples of the lower alkyl group of R ²⁵ and R ^{26 in} the neutral alkyl-substituted TCNQ represented by are methyl group, ethyl group, propyl group and the like. The TCNQ single salt used in the present invention can be easily obtained by reacting a halide of a nitrogen-containing heterocyclic compound cation with a Li salt of TCNQ by heating in a solvent such as methanol. Is enough.

Further, the TCNQ complex salt (complex) used in the present invention utilizes the reducibility of iodo ion I ⁻ to produce a nitrogen-containing heterocyclic compound cation iodide D ₁ ⁺ I ⁻ , D ₂ ⁺ I ⁻ , D ₃ ⁺ I ⁻ . Molar ratio of neutral TCNQ
3: 4 or by reacting the same cations D ₁ ⁺ , D ₂ ⁺ , D ₃ ⁺ halides with TCNQ Li salt The compound obtained by a method known per se, such as a method of doping the same with neutral TCNQ, can be used without exception.

In the present invention, a nitrogen-containing heterocyclic compound which is a constituent component of each of two or more kinds of single salts or a combination of two or more kinds of complex salts, or a combination of a single salt and a complex salt is They may be the same or different from each other. Further, in the present invention, it is possible to use an alkyl-substituted TCNQ instead of the neutral TCNQ, and further to use a TCNQ single salt, a TCNQ complex salt, an alkyl-substituted TCNQ single salt, or an alkyl-substituted TCNQ complex salt. That should be possible theoretically. That is, according to the method of the present invention, TCNQ and alkyl-substituted TC are used as the acceptor moiety.
Any combination of NQ is possible, and any combination of two or more nitrogen-containing heterocyclic compounds can be used as a donor part.

According to the method of the present invention, for example, the above general formula [I] In the TCNQ complex represented by, any of m having an arbitrary value in the range of 0 <m ≦ 3.5 can be produced.

That is, for example, if 1 <m ≦ 3.5 is desired, this can be obtained by subjecting a mixture consisting of the combination of the above (i), (ii) or (iii) to a heating and melting reaction in the absence of a solvent. , If 0 <m ≦ 1 is desired,
Usually, the desired complex can be easily obtained by the same treatment as above using a mixture consisting of the combination of (i) or (v). When the mixture consisting of the combination of the above (iv) is used, 0 <m ≦ 1 can be prepared or 1 <m ≦ 3.5 can be prepared depending on the kind of TCNQ complex salt used and the combination thereof. You can also

The above-mentioned general formula [I] obtained by the production method of the present invention The TCNQ complex represented by is used in high-performance conductive molecular films, nonlinear optical materials, antistatic agents, molecular devices, biodevices, the design of highly ordered molecular assemblies with electronic functions, or electrolytic capacitors and batteries. It is expected to be used in various organic semiconductor fields such as solid electrolytes.

Reference examples and examples are shown below, but the present invention is not limited to these reference examples and examples.

〔Example〕

Reference example 1. Synthesis of TCNQ single salt (1) Synthesis of TCNQ lithium salt TCNQ 20.4 g (0.1 mol) was dissolved in 1.5 l of acetonitrile under heating, and 26.8 g (0.2 mol) of lithium iodide was added to 200 ml of acetorinitrile. The solution dissolved in was added dropwise, and the mixture was refluxed for 1 hour. After the reaction, the reaction mixture was cooled to collect crystals, and dried to obtain 20.0 g of purple powder crystals. Yield 94.8%.

(2) Iodide of nitrogen-containing heterocyclic compound cation (N
-Synthesis of alkyl quaternary ammonium iodide) An equimolar amount of an organic base and an alkyl iodide are mixed with or without a solvent in a suitable organic solvent, and the boiling point of the solvent is 13
The reaction was carried out at 0 ° C for 0.5 to 10 hours. After the reaction, the mixture was cooled and the precipitated crystals were taken and recrystallized with an appropriate solvent. The results are shown in Table 1.
Shown in (a) and (b).

(3) Synthesis of TCNQ single salt 4.22 g (20 mmol) of lithium salt of TCNQ obtained in (1) was dissolved in 175 ml of methanol with heating, and 20 mmol of iodide of nitrogen-containing heterocyclic compound cation was dissolved in 50 ml of methanol. The solution was added dropwise and the mixture was refluxed for 1 hour. After the reaction, the mixture was cooled to collect crystals, which were recrystallized from acetonitrile to obtain TCNQ single salt. The results are shown in Tables 2 (a) and (b).

The specific resistance values in the table are 25 ° C after molding the sample powder into pellets.
The current value was measured by the two-terminal method, the resistance value R was calculated, and the resistance value R was calculated from the following equation.

ρ = R · A / l where ρ is the specific resistance value (Ω · cm), R is the resistance (Ω), A is the electrode contact area (cm ² ), and 1 is the sample thickness (cm).

The endothermic point and exothermic decomposition point were determined by differential scanning calorimetry (DSC) measurement.

Reference Example 2 Synthesis of TCNQ complex TCNQ (3.06 g, 15 mmol) was dissolved in acetonitrile (150 ml) with heating, and the N-alkyl quaternary ammonium iodide (11.25 mmol) obtained in (2) of Reference Example 1 was dissolved therein. The acetonitrile solution was added dropwise and refluxed for 1 hour. After cooling, the result of precipitation was taken and recrystallized from acetonitrile to obtain a TCNQ complex. Table 3 shows the physical properties of the obtained TCNQ complex.

In the table, neutral TCNQ (denoted as TCNQ °) and anion radical TCN
Q ( (Displayed as) complex composition ratio (A. Rembaum etc., J. Am. Chem. Soc., 93 , 2532 (197
It was determined by the method of ultraviolet absorption spectrum measurement according to 1)).
The endothermic point and exothermic decomposition point were determined by differential scanning calorimetry (DSC) measurement. Regarding the electrical characteristic values, the complex was used as a pellet, and the current-voltage measurement (two-terminal method) was performed at 25 ° C. after the sample was prepared according to the conventional method, and the specific resistance value ρ (Ω · cm) was calculated based on the calculation formula.

Examples 1-38 Reaction of TCNQ Single Salt with TCNQ In a container of Al (or Pt) having high thermal conductivity, Nn-butylisoquinolinium TCNQ single salt 3.9 g (0.01 mol) and TCNQ 4.08 g
(0.02 mol) was sufficiently pulverized and mixed, and the mixture was heated and reacted at 240 ° C. for 1 minute. After the reaction, the container was rapidly cooled, the solidified crystals were taken out, and the target TCNQ complex was obtained as a black-purple powder. Got The specific resistance value (ρ value) of the obtained complex is 10 Ω · cm.
(Two-terminal method).

In addition, this product was recrystallized from acetonitrile to obtain black purple needle crystals. The specific resistance of the recrystallized product is 9Ω ・ cm, The ratio was 1.95.

If the TCNQ addition amount is changed by the same operation, other TCNQ
Table 4 (a) to (d) shows the results when the single salt was used and the experiments using a plurality of TCNQ single salts were performed.

Comparative Example 1 N-n-butylisoquinolinium iodide 3.13 g (0.0
1 mol) and TCNQ 4.08 g (0.02 mol) in acetonitrile 200 ml
The mixture was refluxed for 1 hour in the medium and then left at room temperature for crystallization to precipitate yellow crystals and black-purple short needle crystals. As a result of separating and analyzing each, the yellow crystal was TCNQ and the black purple short needle crystal was It was a TCNQ complex with a ratio of 1.0.

Examples 39 to 62 Reaction of TCNQ complex with TCNQ and reaction between TCNQ complexes N-n-butylisoquinolinium TCNQ complex was placed in a container of Al (or Pt) having high thermal conductivity. 2.97 g (0.005 mol) and TCNQ 1.02 g (0.005 mol) were sufficiently crushed and mixed, and the mixture was heated and reacted at 240 ° C. for 1 minute. After the reaction, the container was rapidly cooled and the solidified crystals were taken out to obtain the target TCNQ complex as a black-purple powder. Got The specific resistance value of this product was 15 Ω · cm.

This product was recrystallized from acetonitrile to give black purple needle crystals. The specific resistance of the recrystallized product is 12Ω ・ cm, The ratio was 1.91.

If the TCNQ addition amount is changed by the same operation, other TCNQ
Table 5 (a) to (c) show the results of experiments using a complex and a plurality of TCNQ complexes.

Examples 63 to 66 Reaction of TCNQ Single Salt with TCNQ Complex 1,2-Dimethyl-in a container of Al (or Pt) having high thermal conductivity
3-n-butyl-1H-imidazolium single salt 1.79 g (0.005
mol) and 1,2-dimethyl-3-n-butyl-1H-imidazolium complex 2.81 g (0.005 mol) was sufficiently pulverized and mixed, and the mixture was heated and reacted at 220 ° C. for 1 minute. After the reaction, the container was rapidly cooled, and the solidified crystals were taken out to give the desired TCNQ complex as a black-purple powder. Got The specific resistance value of this product was 30 Ω · cm. The product was recrystallized from acetonitrile to obtain black purple plate crystals. The specific resistance of the recrystallized product is 25Ω ・ cm, The ratio was 0.45.

Hereinafter, the same operation was performed using Nn-butylisoquinolinium single salt and its complex, and the results in Table 6 were obtained.

Example 67 1.95 g (0.005 mol) of Nn-butylisoquinolinium TCNQ single salt and 2-methyl-7,7,8,8-tetracyanoquino in a container of Al (or Pt) having high thermal conductivity. Dimethane (2-MTCNQ)
1.09g (0.005mol) is pulverized and mixed thoroughly, and put at 240 ℃ 1
The mixture was heated and reacted for a minute. After the reaction, the container was rapidly cooled, the solidified crystals were taken out, and the target TCNQ complex Got The specific resistance value of this product was 220 Ω · cm.

Example 68 2,6-Dimethyl-7,7,8,8-tetracyanoquinodimethane (2,5-DMTCNQ) 1.16 g (0.005 mol) instead of 2-MTCNQ
Was operated in the same manner as in Example 67 to obtain the target TCNQ complex. Got

The specific resistance value of this product was 220 Ω · cm.

〔The invention's effect〕

As described above, the present invention provides a novel method for producing a TCNQ complex useful in the field of organic semiconductors, and according to the method of the present invention, various complex composition ratios that cannot be obtained by conventional methods are provided. A TCNQ complex having, that is, the above general formula [I] In the TCNQ complex represented by, TCNQ complexes having various constitutional ratios, in which the value of m is variously changed, can be arbitrarily produced according to the purpose, and the effect is remarkable. The contribution is extremely large.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location C07D 233/58 235/06 263/04 295/02

Claims (1)

[Claims] 1. A general formula [I] [D ₁ ⁺ ] _p. [D ₂ ⁺ which is characterized by subjecting a mixture comprising any combination of the following (i) to (v) to a heat-melting reaction. ] _q・ [D ₃ ⁺ ] _r・ [R-TCNQ °] _m [I] [wherein [D ₁ ⁺ ] _, [D ₂ ⁺ ] and [D ₃ ⁺ ] are independently the following general formulas [II] to [XVIII] (Wherein R ¹ , R ² , R ³ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹² ,
R ¹³ , R ¹⁶ , R ¹⁷ , R ¹⁸ , R ¹⁹ , R ²¹ , R ²² , R ²³ , and R ²⁴ each independently represent an alkyl group or an aralkyl group, and R ⁴ and R ⁵
Are each independently a hydrogen atom or a methyl group, and R ¹¹ , R
¹⁴ , R ¹⁵ and R ²⁰ each independently represent a hydrogen atom or an alkyl group. Represents an N-substituted nitrogen-containing heterocyclic compound cation selected from Represents a 7,7,8,8-tetracyanoquinodimethane anion radical, and [R-TCNQ °] is represented by the following general formula [XIX] (However, R ²⁵ and R ²⁶ each independently represent a hydrogen atom or a lower alkyl group.), A neutral 2-alkyl-, 2,5-dialkyl- or unsubstituted 7,7,8, 8-tetracyanoquinodimethane, where p, q and r are each independently p
+ Q + r = 1 represents a value satisfying 1 and m represents a value in the range of 0 <m ≦ 3.5. ] The manufacturing method of the organic electroconductive complex shown by these.