JP2008280299A - Non-covalent bond polymer and molecular device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new non-covalent bond polymer that has a simple chemical structure and does not require a complicated process in its synthesis and its molecular device. <P>SOLUTION: The non-covalent bond polymer is formed from a long-chain alkylurea represented by formula (wherein R<SB>1</SB>and R<SB>2</SB>are each a 10-30C long-chain alkyl group) by self-organization. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a novel non-covalent polymer and molecular device, and more particularly, a novel non-covalent bond formed from a urea compound containing a long-chain alkyl urea by utilizing self-assembly based on intermolecular interaction. The present invention relates to a polymer and its molecular device.

In recent years, it has been studied to control a regular structure or atomic arrangement in the order of several nanometers to several tens of nanometers.
Although this control can be performed by current processing technology, the control is limited. Further, it takes a very long time for processing or a high-cost processing method.
For this reason, a polymer in which a metal complex or an organic compound is self-organized has been proposed.
Self-assembled polymers are attracting attention as functional materials such as various functional materials such as electronic device elements, electroluminescence or catalytic ability, spectroscopic, magnetic or electrochemical composite films.

For example, a molecular film formed by self-assembly of interaction between a noble metal or a transition metal and a sulfonium group of a polymer having a sulfonium group has been proposed (Patent Document 1).
Also proposed is a nanowire with metallic properties such as magnetic function, electroluminescence function, conductivity function, catalytic ability, etc. of complex compound structure in which metal complex is embedded in double-headed lipids having hydrophilic groups at both ends (Patent Document 2).
Furthermore, a columnar liquid crystal compound exhibiting ferroelectricity in which urea derivative molecules are stacked in a columnar shape has been proposed (Patent Document 3).
The organic-inorganic composite film structure formed by introducing multiple hydrogen bonds into the ligand skeleton and incorporating various metal ions as the central metal by utilizing its self-organizing ability is colored depending on the type of the central metal. A transition metal complex nano-thin film has been proposed (Patent Document 4).

JP 2001-315254 A JP 2005-255543 A JP 2006-16352 A JP 2006-124349 A

All of the molecular films specifically described in Patent Document 1 are sulfonium compounds using a noble metal as a starting material.
The nanowires specifically described in the above Patent Document 2 are functionally limited, for example, proton conductivity cannot be expected, the structure of the starting material is complicated, and the synthesis process requires multiple steps. .
The columnar liquid crystal compound specifically described in Patent Document 3 is functionally limited. For example, proton conductivity is not described, and atomic emission phenomenon cannot be expected.
Furthermore, the nano thin film specifically described in the above-mentioned Patent Document 4 is a polycyclic aromatic compound having a complicated structure as a starting material.
Therefore, a novel non-covalently bonded polymer formed by utilizing self-assembly based on intermolecular interaction from a starting material having a simple chemical structure without requiring a complicated process is not known.

  An object of the present invention is to provide a novel non-covalent polymer and a molecular device thereof that have a simple chemical structure and do not require a complicated process.

  The present invention relates to a noncovalently bonded polymer formed by self-assembly from a urea compound containing a long-chain alkylurea represented by the following formula.

（式中、Ｒ_１およびＲ_２は炭素数１０〜３０の直鎖アルキル基である。）

(In the formula, R ₁ and R ₂ are linear alkyl groups having 10 to 30 carbon atoms.)

The present invention also relates to a molecular device that utilizes the anhydrous proton conductivity of the non-covalently bonded polymer.
The present invention also relates to a molecular nanowire that utilizes the electronic conductivity of the noncovalent polymer.
The present invention also relates to a molecular device that utilizes the atomic emission phenomenon of the non-covalently bonded polymer.

  According to the present invention, it is possible to provide a novel non-covalently bonded polymer and its molecular device or molecular nanowire that have a simple chemical structure and do not require a complicated process of synthesis.

A preferred embodiment of the present invention will be described below.
1) The noncovalently bonded polymer as described above, wherein the urea compound is a urea compound composed only of a long-chain alkylurea.
2) The non-covalently bonded polymer, wherein the urea compound is a rare earth metal complex represented by the following formula.

(In the formula, R ₁ and R ₂ are long-chain alkyl groups having 10 to 30 carbon atoms, M is a rare earth element, X is a halogen element, m and n indicate a molar ratio, and m + n = 1. )
3) The noncovalent polymer described above, wherein the rare earth element is Tb, Tm, or Eu.
4) The noncovalent polymer described above, wherein m = 0.29 and n = 0.71 in the above formula.

The non-covalently bonded polymer of the present invention can be obtained by forming a urea compound containing the long-chain alkylurea by self-assembly.
And as such a urea compound containing long-chain alkyl urea, the urea compound which consists only of long-chain alkyl urea, or the long-chain alkyl urea-rare earth metal complex shown by said chemical formula is mentioned.

As the urea compound consisting only of the long-chain alkyl urea, in the above chemical formula, R ₁ and R ₂ are linear alkyl groups having 10 to 30 carbon atoms, preferably 14 to 30 carbon atoms, and R ₁ and R ₂ are Different or identical compounds such as 1,3-didecylurea, 1,3-diundecylurea, 1,3-dilaurylurea, 1,3-ditridecylurea, 1,3-dimyristylurea, 1,3- Dipentadecyl urea, 1,3-dicetyl urea, 1,3-diheptadecyl urea, 1,3-diocudadecyl stearyl urea, 1,3-dinondecyl urea, 1,3-diecosyl urea, 1,3-diceryl urea, 1, Examples include 3-dimelicil urea.
In the above urea compound and long-chain alkylurea-rare earth metal complex, by having a long-chain alkyl, particularly a straight-chain long-chain alkyl group, a polymer having high regularity and thus high proton conductivity can be obtained. .

Also, the long-chain alkyl urea - the rare earth metal complex, _{R 1} and _{R 2} in the above formula is a straight-chain alkyl group having 10 to 30 carbon atoms, preferably 14 to 30, _{R 1} and _{R 2} May be different or the same, M is a rare earth element, preferably Tb, Tm or Eu, X is a halogen element, preferably Cl, m and n indicate a molar ratio, and m + n = 1 Preferred examples include urea compounds in which m = 0.29 and n = 0.71.

The long-chain alkyl urea is obtained, for example, by dehydration by heating an ammonium carbamate complex obtained by reacting a long-chain alkylamine by flowing carbon dioxide in a solvent to a temperature of about 100 to 200 ° C. be able to.
The long-chain alkylurea-rare earth metal complex separates the product after reacting the long-chain alkylurea with the rare earth metal halide (III) (hexahydrate) in a solvent. Can be obtained.
There is no restriction | limiting in particular as said solvent, For example, tetrahydrofuran (THF), acetone, methanol, ethanol, acetonitrile, or these mixtures can be mentioned.

The non-covalent polymer of the present invention is obtained by separating a product after self-organizing a long-chain alkylurea compound or a long-chain alkylurea-rare earth metal complex based on intermolecular interaction in a solvent. Can do.
There is no restriction | limiting in particular as said solvent, For example, tetrahydrofuran (THF), acetone, methanol, ethanol, acetonitrile, or these mixtures can be mentioned.

The long-chain alkylurea compound or the long-chain alkylurea-rare earth metal complex is preferably dispersed uniformly in a solvent and self-assembled, and particularly preferably dissolved and self-assembled.
The self-assembly can be appropriately selected within the range of 20 to 100 ° C. and 1 minute to 24 hours.
The separation can be performed by appropriately combining extraction, filtration, washing, recrystallization, and the like.

The non-covalently bonded polymer of the present invention is a polymer compound obtained by polymerizing the long-chain alkylurea compound or the long-chain alkylurea-rare earth metal complex by self-assembly.
In this case, when the precursor compound is composed only of the long-chain alkylurea compound, it is considered that the low-molecular compound overlaps in a columnar shape due to intermolecular interaction due to hydrogen bonding and self-assembles to form a polymer.
In the case of a long-chain alkylurea-rare earth metal complex, it is considered that a long-chain alkylurea is spirally overlapped on the rare earth halide and self-assembles to form a polymer.

The non-covalently bonded polymer of the present invention has proton conductivity in an anhydrous state which is considered to be due to a hydrogen bond network from its structure, and has a possibility as a molecular device utilizing the property.
In addition, the noncovalent polymer derived from the long-chain alkylurea-rare earth metal complex of the present invention is considered to have electronic conductivity due to the centrally arranged metal because of its structure, and it can be used as a molecular nanowire utilizing its properties. There is.
In addition, since the non-covalently bonded polymer derived from the long-chain alkylurea-rare earth metal complex of the present invention exhibits an atomic luminescence phenomenon, there is a possibility as a molecular device utilizing the atomic luminescence phenomenon.
In the above case, the emission wavelength can be changed depending on the difference in the central metal, and there is a possibility as a molecular device using an atomic emission phenomenon by combining two or more central metals.

Example 1
200 g of ethanol was added to 2.0 g (7.4 mmol) of n-octadecylamine (Tokyo Chemical Industry Co., Ltd.), and the mixture was stirred at 0 ° C. for 12 hours while flowing carbon dioxide. Thereafter, since a white precipitate was deposited in the reaction solution, filtration was performed. The remaining solid was added to ethanol, stirred at room temperature, filtered again, and washed several times with ethanol. The product was dried under reduced pressure using a vacuum pump to obtain an intermediate product, ammonium carbamate complex (yield 2.0 g, yield 93%). This ammonium carbamate complex was melted in an autoclave (CO ₂ atmosphere) at 160 ° C., dehydrated for 24 hours, and then self-assembled to yield a product in which 1,3-dioctadecylurea was self-assembled (yield) 1.2 g, yield 62%).

Elemental analysis and infrared absorption spectrum measurement were performed to identify this product.
As a result of elemental analysis, a theoretical value and an actual measurement value were approximately approximated.
The results of elemental analysis are shown below.
Elemental analysis result Calculated value (measured value) (%)
C 78.65 (78.70)
H 13.56 (14.23)
N 4.96 (4.86)
From this result, the product is considered to be a polymer in which the target compound represented by the following chemical formula is self-assembled.

（前記の化学式において、Ｒ_１およびＲ_２がｎ−オクチル基である。）

(In the above chemical formula, R ₁ and R ₂ are n-octyl groups.)

Further, the infrared absorption spectrum results of the measurement, the N-H peak 3350 cm ^-1, the C = O peak of 1650 cm ^-1, the N-H peak of 1570 cm ^-1, a peak of C-N is 1320cm ^The product shows a spectrum attributed to the typical association of the secondary amide (—NH—CO—), with the absorption of C═O that should be observed most strongly reversed. It showed weak absorption. This is believed to be due to the effect of hydrogen bonding interactions.

Subsequently, in order to clarify the thermophysical properties of the product, thermogravimetry and differential scanning calorimetry were performed. As a result, thermogravimetry revealed that the product was a crystalline compound having a decomposition temperature of 165 ° C. and a melting point (53 ° C.) only. Is enthalpy change and entropy change at 53 ℃ △ H, △ S is, △ _H KI = 121kJmol ^-1, was △ _S KI = 371JKmol ^-1.
The decomposition temperature indicates a 10% by mass decrease temperature recorded at a rate of temperature increase of 10 ° C./min in N ₂ .

Further, when the product was rapidly cooled from a high temperature state to room temperature, or slowly cooled from a high temperature state to room temperature, proton conductivity in an anhydrous state was determined at 80 ° C. (solid 2).
The results were as follows.
Proton conductivity Rapid cooling from high temperature to room temperature 3.2 × 10 ⁻¹³ S / cm
Slow cooling from high temperature to room temperature 5.6 × 10 ⁻¹³ S / cm
80 ° C. (solid 2) 3.6 × 10 ⁻⁷ S / cm

Example 2
4.8 g (8.6 mmol) of 1,3-dioctadecylurea obtained in the same manner as in Example 1 and terbium (III) trichloride hexahydrate [TbCl ₃ · 6H ₂ O] (Kanto Chemical Co., Inc.) To 0.94 g (3.5 mmol), 1000 ml of a mixed solvent of THF: EtOH = 1: 1 was added and heated to 40 ° C. to dissolve. After dissolution, after 12 hours, a white precipitate was precipitated in the reaction solution, and filtration was performed. The remaining solid was added to ethanol, stirred at room temperature, filtered again, and then several times with ethanol. Washed. Finally, it was dried under reduced pressure using a vacuum pump to obtain a product (yield 3.2 g, yield 55%) in which 1,3-dioctadecylurea-rare earth metal complex was self-assembled.

Elemental analysis and infrared absorption spectrum measurement were performed to identify this product.
The results of elemental analysis are shown below.
Elemental analysis result Calculated value (measured value) (%)
C 72.94 (70.79)
H 12.58 (13.16)
N 4.60 (4.52)
Tb − (14.99)

  As a result of elemental analysis, a theoretical value and an actual measurement value were approximately approximated. From this result, the product is considered to be a polymer in which the target compound represented by the above chemical formula is self-assembled.

（前記の化学式において、ＭがＴｂ、ＸがＣｌであり、Ｒ_１およびＲ_２がｎ−オクチル基であり、ｍ＝０．２９、ｎ＝０．７１である。）

(In the above chemical formula, M is Tb, X is Cl, R ₁ and R ₂ are n-octyl groups, and m = 0.29 and n = 0.71.)

In addition, the content of Tb atoms can be confirmed from the results of ICP-MS, and it was found that the intended polymer was obtained in consideration of the results and the results of elemental analysis. It was also found that TbCl ₃ was coordinated to 2.4 molecules per molecule (corresponding to m = 0.29 and n = 0.71 in the chemical formula).
Furthermore, from the IR spectrum, an N—H peak was observed at 3450 cm ⁻¹ , a C═O peak at 2050 cm ⁻¹ , and a C—N peak at 1610 cm ^−1, which was stabilized by coordination with the Tb ion. It was found that the absorption of the converted C═O stretch and C—N stretch was shifted to the high wavenumber side compared to the case of the product of Example 1. That is, the presence of coordination bonds in this product was confirmed.

Subsequently, in order to clarify the thermophysical properties of the obtained product, thermogravimetry and differential scanning calorimetry were performed. As a result, the product was found to have a decomposition temperature of 238 ° C. In addition, from the results of differential scanning calorimetry, several endothermic and exothermic peaks indicating phase transition were observed, and it was found that liquid crystallinity was exhibited in the temperature range of 112 to 179 ° C., considering the results of observation with a polarizing microscope. . Enthalpy change and entropy change from the solid at 112 ° C. is a transition temperature to a liquid crystal phase _{(T KC) △ H KC,} △ S KC ^{_{value, △ H KC = 34kJmol -1,}} △ S KC = 89JK -1 mol -1 Met. Enthalpy change and entropy change △ _{H CI} in a phase transition temperature to isotropic phase _{(T CI)} is 179 ° C. a liquid crystal phase, △ _{S CI ^{value, △ H CI = 1.0kJmol -1,}} △ S CI = 2 .2JK ⁻¹ mol ⁻¹ .

Further, considering the result of the powder X-ray diffraction measurement, it was found that the liquid crystal phase forms a columnar phase having a rectangular lattice.
From the above results, it was revealed that this product was a thermotropic liquid crystal metal complex in which 2.4 molecules of 1,3-dioctadecylurea were coordinated to 1 molecule of TbCl ₃ . Moreover, it turned out that columnar liquid crystallinity is shown in the temperature range of 112-179 degreeC.

In addition, when the product was rapidly cooled from the liquid crystal state to room temperature, or slowly cooled from the liquid crystal state to room temperature, proton conductivity in an anhydrous state was determined at 70 ° C. (Isotropic) and 120 ° C. (LC1).
The results were as follows.
Proton conductivity Rapid cooling from liquid crystal state to room temperature 7.1 × 10 ⁻¹³ S / cm
Slow cooling from liquid crystal state to room temperature 3.7 × 10 ⁻¹² S / cm
70 ° C. 3.6 × 10 ⁻¹² S / cm
120 ° C. 1.4 × 10 ⁻⁶ S / cm
A proton conductivity measurement diagram of this product at 120 ° C. is shown in FIG.

Moreover, the luminescence phenomenon was observed about this product. The results are summarized in FIG.
The emission color was green.

Example 3
Instead of terbium (III) trichloride hexahydrate _{[TbCl 3 · 6H 2 O]} , except for using the europium (III) trichloride hexahydrate _[TbCl 3 · _6H 2 O] in the same manner as in Example 2 The product was obtained.
This product was a liquid crystalline product, and the emission wavelength varied depending on the difference in the central metal.
This product is considered to be a polymer in which the compound represented by the chemical formula is self-assembled.

（前記の化学式において、ＭがＥｕ、ＸがＣｌであり、Ｒ_１およびＲ_２がｎ−オクチル基であり、ｍ＝０．２９、ｎ＝０．７１である。）

(In the above chemical formula, M is Eu, X is Cl, R ₁ and R ₂ are n-octyl groups, and m = 0.29 and n = 0.71.)

FIG. 1 is a schematic diagram showing non-covalent polymerization by self-assembly of a urea compound consisting only of a long-chain alkylurea according to one embodiment of the present invention. FIG. 2 is a schematic diagram showing the formation of a noncovalent polymer by self-organization of a long-chain alkylurea-rare earth metal complex according to one embodiment of the present invention. FIG. 3 shows a proton conductivity measurement diagram of the product of Example 2 at 120 ° C. FIG. 4 shows the result of observing the luminescence phenomenon of the product of Example 2.

Claims (8)

A non-covalently bonded polymer formed by self-assembly from a urea compound containing a long-chain alkyl urea represented by the following formula.

(In the formula, R ₁ and R ₂ are long-chain alkyl groups having 10 to 30 carbon atoms.)   The non-covalently bonded polymer according to claim 1, wherein the urea compound is a urea compound composed only of a long-chain alkyl urea. The non-covalently bonded polymer according to claim 1, wherein the urea compound is a rare earth metal complex represented by the following formula.

(In the formula, R ₁ and R ₂ are long-chain alkyl groups having 10 to 30 carbon atoms, M is a rare earth element, X is a halogen element, m and n indicate a molar ratio, and m + n = 1. )   The non-covalently bonded polymer according to claim 3, wherein the rare earth element is Tb, Tm, or Eu.   5. The non-covalently bonded polymer according to claim 3, wherein m = 0.29 and n = 0.71 in the above formula.   A molecular device using proton conductivity of the non-covalently bonded polymer according to any one of claims 1 to 5 in anhydrous form.   The molecular nanowire using the electronic conductivity of the non-covalently-bonded polymer according to any one of claims 1 and 3-5.   A molecular device that utilizes the atomic emission phenomenon of the non-covalently bonded polymer according to claim 1.

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