JP4534017B2 - One-dimensional array of 1,2,4,5-tetra-substituted benzene or a polynuclear aromatic hydrocarbon molecularly encapsulated zeolite having a linear shape in which 2 to 5 benzene rings are condensed and a method for producing the same - Google Patents

Description

The present invention relates to a polynuclear aromatic hydrocarbon molecule assembly having a linear shape in which 2 to 5 benzene rings are condensed in a substantially one-dimensionally arranged 1,2,4,5-tetrasubstituted benzene or benzene ring. Further, a zeolite containing a polynuclear aromatic hydrocarbon molecular aggregate having a linear shape in which 2 to 5 benzene rings are condensed in a substantially one-dimensional array of 1,2,4,5-tetrasubstituted benzene and It relates to a manufacturing method. In addition, hereinafter, one-dimensionally arranged 1,2,4,5-tetrasubstituted benzene or a linear polynuclear aromatic hydrocarbon having 2 to 5 condensed benzene rings may be referred to as an anthracene-like compound. In particular, the present invention relates to an AFI single crystal zeolite having an extremely large amount of one-dimensionally arrayed anthracene-like compounds and a method for producing the same.

Anthraxene is an electron-donating molecule, and has a transition moment due to its chemical structure. It is one of the important functional molecules in light-emitting materials, complex crystals, and molecular electronics research, and many research reports have been made. ing.
For example, a technique for arranging a dimer of a compound having a π-electron conjugated structure such as anthracene as an organic nonlinear optical material in a clad layer has been reported (Patent Documents 1 and 2). However, these techniques are only a study of dimers of anthracene molecules.
In addition, in order to avoid a time-dependent change of a functional molecule such as anthracene, a technique has been reported in which the functional molecule is included in a polymer forming a shell structure to stabilize the functional molecule (Patent Document 3). ) However, this technique is a technique for avoiding a time-dependent change of functional molecules such as anthracene, and does not pose any problem as to how the functional molecules are encapsulated.

On the other hand, zeolite is a general term for crystals in which tetrahedral structures centered on silicon or aluminum share oxygen atoms at their vertices to form a three-dimensional grid. Zeolites are divided into several types depending on the ratio of silicon and aluminum present. In addition, in the zeolite, aluminum that should be trivalent originally becomes tetravalent, so the zeolite skeleton is negatively charged. Therefore, there exists a charge compensating cation that compensates for this negative charge. The chemistry of the zeolite will vary significantly depending on the ratio of silicon and aluminum, the type of charge compensating cation, etc.
Furthermore, zeolite is a crystal having uniform pores regularly arranged at the molecular level, and has a chemical / physical adsorption action that is shape-selective or due to the framework structure. (Molecular sieves), separation adsorbents for various organic compounds, isomerization catalysts and disproportionation catalysts for aromatic compounds, etc. are widely used industrially.
And although the technology which captures a hydrophilic substance, a polar compound, etc. to zeolite is reported (patent documents 4), there is only the technique which supplements in a layer form (two dimensions) there, There is no suggestion of one-dimensional arrays.

JP-A-6-347846 JP-A-7-225402 JP 2003-95999 A JP 2004-219212 A

In the molecular assembly of anthracene-like compounds, when the relative arrangement of the anthracene-like compounds is forcibly controlled, the interaction between the molecules can be expected to change, and new properties can be expressed. It can be expected to be used in different ways. Furthermore, in the molecular assembly of anthracene-like compounds, especially if a system in which the orientation of anthracene-like compound molecules having an anisotropic shape is controlled and one-dimensionally arranged at high density can be created, a one-dimensional arrangement is possible. Anthracene-like compound molecular aggregates are expected to be used as new molecular devices and wires due to changes in electron mobility based on π-π interactions between molecules.
Accordingly, an object of the present invention is to provide an anthracene-like compound molecular assembly having a substantially one-dimensional arrangement, and a substantially one-dimensionally arranged anthracene-like compound in which the relative arrangement between molecules is forcibly controlled. It is to provide a molecular assembly. Another object of the present invention is to provide a zeolite containing an anthracene-like compound molecular assembly that is substantially one-dimensionally arranged, and a method for producing the same, and to substantially control the relative arrangement between molecules. It is intended to provide a zeolite containing the anthracene-like compound molecular assembly and a method for producing the same. Furthermore, it is to provide a zeolite in which an anthracene-like compound is encapsulated at a high density, particularly a zeolite in which the number of anthracene-like compounds is 10 ¹² / cm ² or more, and a method for producing the same.

The inventors of the present invention, while intensively researching to solve the above-mentioned problems, are surprised by the anthracene-like compound-containing zeolite obtained by selecting a specific zeolite single crystal and contacting the zeolite with an anthracene-like compound molecule. What should be said is that it is a zeolite characterized by including an anthracene-like compound molecular assembly that is substantially one-dimensionally arranged, and that visible light absorption and infrared light absorption are anthracene-like compound molecular assembly. The observation was made that there was an oscillating electric field of light in the direction of the alignment. Based on this finding, the present inventors have made further studies and finally completed the present invention.

That is, the invention of claim 1 is a molecular assembly of polynuclear aromatic hydrocarbons having a linear shape in which 2 to 5 benzene rings are condensed in a one-dimensional array substantially in the longitudinal direction of the molecule. It is an AFI single crystal zeolite characterized by enclosing the body. Here, the meaning of the one-dimensional arrangement is, for example, as shown in FIG. 1 which is a schematic diagram of arranged anthracene molecules present in the one-dimensional pores of the AFI crystal drawn from the data of Example 2 below. Furthermore, it means a state in which anthracene-like compounds are arranged one-dimensionally in the major axis direction of the molecule in the zeolite pores. Moreover, substantially means that most of the encapsulated compounds are arranged one-dimensionally, and a small part of the compounds are not arranged one-dimensionally. Although it is desirable that all the compounds are completely arranged in one dimension, in the technique disclosed in the present invention, it may not be said that all the compounds are arranged completely in one dimension. Even if the compounds are not one-dimensionally arranged, it indicates that such a molecular assembly belongs to the molecular assembly of the present invention as long as the initial object of the present invention can be achieved.

The invention of claim 2 is an invention in which the anthracene-like compound molecular assembly that is substantially one-dimensionally arranged in the invention of claim 1 is densely encapsulated , and the number of encapsulated compounds is 10 ¹² / cm 2. ^The invention of ² or more is the invention of claim 3. Moreover, the amount of the encapsulated compound can be 10% by weight or less with respect to the zeolite. Furthermore, in the invention according to any one of claims 1 to 3, the polynuclear aromatic hydrocarbon molecule having a linear shape in which 2 to 5 benzene rings are condensed is selected from naphthalene, anthracene, and pentacene. invention is that an invention of claim 4.

The invention according to claim 5 is characterized in that a linear polynuclear aromatic hydrocarbon molecule in which 2 to 5 benzene rings are condensed is brought into contact with AFI single crystal zeolite, substantially in the major axis direction of the molecule. This is a method for producing an AFI single crystal zeolite including an anthracene-like compound molecular assembly in which molecules are one-dimensionally arranged. The anthracene-like compound to be contacted is preferably in the gas phase. In the invention of claim 5, a polynuclear aromatic hydrocarbon molecules of the linear shape AFI monocrystalline zeolite with a benzene ring has 2-5 Kochijimiwa vacuum sealed in a container, the invention is heating of claim 6 It is an invention.

The present invention is described in detail below.
The 1,2,4,5-tetrasubstituted benzene or the linear polynuclear aromatic hydrocarbon in which 2 to 5 benzene rings are condensed refers to the following compounds. 1,2,4,5-tetrasubstituted benzene. Here, the substituent is a methyl group, an ethyl group, a chlorine atom, a fluorine atom, an amino group, or a carboxyl group, and is substituted with the same group. Naphthalene, benzene, anthracene, tetracene, pentacene, and a compound that takes a linear shape as a result of the condensed ring. Those compounds having a substituent. Here, the substituents are the same as described above. In addition, the position of the substituent is substituted so as not to prevent the compound from taking a linear shape. Compounds in which a so-called hetero atom exists in the condensed ring of these compounds. Here, there are a nitrogen atom, an oxygen atom, and a sulfur atom as the hetero atoms.
Specifically, naphthalene, anthracene, tetracene, pentacene, 1,2,4,5-benzenetetracarboxylic acid, 1,2,4,5-benzenetetracarboxylic anhydride (pyromellitic anhydride), acridine, 6, Examples thereof include 7-benzoquinoline and phenazine.
These anthracene-like compounds may be synthesized by a known method, but can be easily obtained by purchasing a commercial product.

In the present invention, it is necessary that these molecules are forcibly controlled. That is, it is necessary that anthracene-like compounds are arranged one-dimensionally in the zeolite pores to form a molecular assembly. Here, 1,2,4,5-tetra-substituted benzene or a polynuclear aromatic hydrocarbon having a linear shape in which 2 to 5 benzene rings are condensed have π electron clouds of the compound overlapping each other. preferable. When placed in such a state, π-π between the molecules of 1,2,4,5-tetrasubstituted benzene or a polynuclear aromatic hydrocarbon having a linear shape in which 2 to 5 benzene rings are condensed. This is because a change in electron mobility based on the interaction provides a better effect.

In the present invention, the term “zeolite” refers to a crystalline microporous material whose constituent elements of the skeleton structure are substantially composed of Si, Al, and O. Examples of zeolite include crystalline aluminosilicate, crystalline metallosilicate, crystalline aluminophosphate, etc., and some elements such as aluminum are replaced with metals such as gallium, iron, titanium, boron, cobalt, chromium, etc. However, the present invention is not limited to these.

In the present invention, any zeolite can be used as long as it can achieve the intended purpose. Among them, a zeolite crystal having a one-dimensional pore is preferable. Here, the zeolite having a one-dimensional pore means a pore having an inner diameter of about 1 nm or less that penetrates substantially straight from the crystal surface to the back surface when one crystal is viewed from an arbitrary orientation. A zeolite having at least one. Here, the term “through substantially straight” means to penetrate through a straight line that can achieve the intended purpose of the present invention.
As the zeolite of the present invention, so-called single crystal zeolite is also preferably used, and MOR single crystal, LTL single crystal, AFI single crystal, and MFI single crystal are particularly preferable. Furthermore, an AFI single crystal is more preferable.
Here, the single crystal is a known one, for example, Atlas.
of Zeolite Structure types, 17 (1/2), WM
This is described in detail in the description of Meier, DH Olson, Ch. Baerlocher, Zeolites, 1996.

A schematic diagram of the AFI crystal used in the present invention is shown in FIG. Here, pores having a diameter of 0.73 nm are formed between the frameworks. More preferably, the length of the AFI crystal in the c-axis direction is 100 μm or more.
The size of the crystal can be determined using an optical microscope, a scanning electron microscope (SEM), or the like.

These zeolites may be natural or synthetic zeolites. Synthetic zeolite is preferred in that the composition of the zeolite can be freely controlled. A conventionally known method can be adopted as a synthesis method. Moreover, you may purchase a commercial item.

In the present invention, the above zeolite and anthracene are brought into contact with each other to produce a zeolite encapsulated in a unitary oriented anthracene molecular assembly. The anthracene is oriented in a controlled manner within the pores in the zeolite.
When the AFI crystal is selected as the zeolite, anthracene is integrated and contained in pores having a diameter of 0.73 nm.

The amount of anthracene to be brought into contact with the zeolite may bring about a good result if the amount of anthracene is excessive with respect to the amount of space in which the anthracene is contained. Anthracene is preferably added to the reaction vessel in the form of crystals, and when it comes into contact with zeolite, it is preferably sublimated and gaseous.
The anthracene to be contacted with the zeolite is preferably contacted in an inert gas atmosphere, a reduced pressure state or a vacuum state in addition to a known reaction vessel. At this time, it is desirable to heat to about 60 to 130 ° C. The reaction time is about 1 hour to 2 weeks.

In addition, as for the zeolite to be used, it is desirable to remove beforehand the crystal water in zeolite and the organic substance used at the time of synthesis. The organic matter at the time of synthesis can be removed by baking by heating at about 700 ° C. in the atmosphere, and the crystal water can be removed by heating at 200 to 500 ° C. in a vacuum state of 10 ⁻² Pa or less. it can.

In the zeolite produced by the present invention, characterized in that the anthracene-like compound characterized by substantially one-dimensional arrangement, or the anthracene-like compound molecular assembly that is substantially one-dimensionally arranged is contained. The amount of the anthracene-like compound encapsulated is large. For example, when an AFI crystal is used, the pores in the crystal can exist at a high density of 10 ¹² / cm ² to 10 ¹⁴ / cm ² . Moreover, it can exist so that it may become about 10 wt% with respect to a zeolite. In the present invention, the linear density of anthracene molecules constituting individual one-dimensional aggregates may be 1.2 × 10 ⁷ / cm. This means that the anthracene molecules are in contact with each other or overlap each other.
Therefore, changes in electron mobility based on π-π interactions between molecules of anthracene-like compounds are expected to be used as new molecular devices and wires.
The linear density means the number of molecules of the anthracene-like compound encapsulated in the zeolite crystal pores per unit length in the c-axis direction of the zeolite crystal pores.
The linear density is calculated from the measured weight ratio of the anthracene-like compound to the number of constituent molecules (molar ratio) contained per unit cell of the anthracene-like compound, and the zeolite lattice constant in the direction parallel to the one-dimensional pore of the zeolite. The line density can be determined by dividing by.
Also, based on the idea that all one-dimensional pores of zeolite crystals are filled with anthracene-like compound molecules and form an anthracene-like compound molecular aggregate, the surface density of the anthracene-like compound molecular aggregate is It can be said that it is equal to the surface density of the one-dimensional pores of the zeolite crystal.

According to the present invention, a polynuclear aromatic having a linear shape in which 2 to 5, 1,2,4,5-tetrasubstituted benzene or benzene rings are condensed, characterized by being substantially one-dimensionally arranged. A hydrocarbon molecular assembly can be easily produced. In this assembly, the relative arrangement between molecules is forcibly controlled, and the interaction between molecules changes, so that a micro device can be constructed. That is, a one-dimensionally arrayed anthracene molecular assembly is produced in a zeolite crystal, so that a macro electrode connection is possible. Furthermore, when the length of the zeolite is 100 μm or more, electrode connection or the like is possible, and use as a microdevice becomes possible.

Hereinafter, the present invention will be described in detail based on examples. The present invention is not limited to these examples.
(Reference Example 1)
(Synthesis of zeolite crystals)
Alumina sol (solid content 10% by weight: manufactured by Kawaken Fine Chemical Co., Ltd.), silica sol (solid content 40% by weight: manufactured by Catalyst Kasei Co., Ltd.), phosphoric acid (85% by weight aqueous solution: manufactured by Wako Pure Chemical Industries, Ltd.), triethylamine (TEA) ( 99% by weight aqueous solution: manufactured by Wako Pure Chemical Industries, Ltd.), deionized water, expressed in oxide notation, Al ₂ O ₃ : P ₂ O ₅ : SiO ₂ : TEA: H ₂ O = 1.1.03: x: It mixed so that it might become 1.55: 750 (molar ratio), and it introduced into the autoclave for hydrothermal synthesis. The value of x can take a value from 0 to 0.3. After sealing, it was allowed to stand at 190 ° C. for 7 days. As a result, when x = 0, the chemical composition is Al ₁₂ P ₁₂ O ₄₈ , and when x = 0.3, the AFI crystal having the chemical composition Al _11.8 P _11.1 Si _1.1 O ₄₈ (c Axial direction: 100 μm) was obtained.
The quality of the AFI crystal obtained by hydrothermal synthesis was confirmed to be almost pure by the measurement of the powder X-ray diffraction pattern with no contamination of impurities. Combining the measurement result of this X-ray diffraction pattern and observation with a scanning electron microscope (FIG. 4), it was found that each hexagonal columnar substance is a single crystal having an AFI structure.
As the X-ray powder diffraction pattern measuring apparatus, RINT-2550V (manufactured by Rigaku Denki) was used.

(Examples 1 to 3) Production of one-dimensionally encapsulated zeolite The AFI crystals obtained in the above Reference Example were heated at 700 ° C. in the air for 48 hours to calcinate and remove the organic amine. Further, the AFI crystal from which the organic amine had been removed was heated to 400 ° C. in a vacuum state of 10 ⁻² Pa or less, and this state was maintained for 2 hours to remove water molecules in the zeolite.
50 mg of this AFI crystal is mixed with 9 mg of anthracene crystal (manufactured by Wako Pure Chemical Industries, Ltd.) without being exposed to the atmosphere, and then sealed in a glass tube and heated at 100 ° C. for 10 days. Anthracene molecules sublimated and adsorbed in the one-dimensional pores of the AFI crystal, and a one-dimensional array of anthracene molecular aggregates was formed in the zeolite pores.
The adsorption amount of the anthracene molecule of this zeolite was 8% by weight. Moreover, the linear density of the anthracene molecule was 1 × 10 ⁷ / cm.
From these results, it can be said that the anthracene molecules are in contact with each other or overlap each other.

A zeolite single crystal encapsulating anthracene molecules is shown in FIG.
Equipment used Scanning microscope: S-4500 (manufactured by Hitachi, Ltd.)

The amount of adsorbed anthracene was measured by CHN-gas chromatographic analysis.
The equipment used is as follows.
Model: EA1110 (manufactured by CE INSTRUMENTS)

When synthesized in the reference example, the AFI crystal, which was colorless and transparent, was colored. This coloring was shown to have strong anisotropy in transmission observation with an optical microscope.
Assuming E // c, the crystal had a dark green color close to black, while E⊥c had a color almost transparent.

The zeolite single crystal encapsulating the anthracene molecule was irradiated with light, and the relationship between photon energy and absorbance was measured separately in the direction of the electric field of the light. The results are shown in FIG. As a result, light absorption occurred in the visible and infrared regions only in the E // c direction. On the other hand, in E⊥c, there is no absorption in visible and infrared, but 3.0-3.8
The multiple vibrational absorption peaks seen in eV are exactly the same as that interpreted as π-π ^* , which is the internal transition of an isolated anthracene molecule. From these facts, the molecules were arranged obliquely parallel to each other as shown in FIG. 1, and it was possible to interpret this as an optical transition caused by the π electrons of the anthracene molecule slightly overlapping with the π electrons of the adjacent molecules.
The equipment used was a self-made polarization microspectroscope (patent pending).

From the above results, it can be said that the anthracene molecules included in the zeolite crystals are in contact with each other or overlap each other, and the interaction between the one-dimensionally arranged anthracene molecules is sufficiently exhibited.

It is a schematic diagram of the arranged anthracene molecule which exists in the one-dimensional pore of an AFI crystal. It is a schematic diagram of the AFI crystal which included nanowire. It is explanatory drawing which showed typically the crystal axis and the electric field direction of light in the case of measuring the light transmission spectrum of the inclusion zeolite single crystal arranged one-dimensionally. 3 is a scanning electron micrograph of the zeolite produced in Example 2. FIG. It is a graph which shows the result of having isolate | separated and measured the relationship between the photon energy and the light absorbency of the anthracene molecule inclusion zeolite single crystal manufactured in Example 2 to the electric field direction of light.

Claims (6)

It is characterized by including a molecular assembly of polynuclear aromatic hydrocarbons having a linear shape in which 2 to 5 benzene rings in which molecules are one-dimensionally arranged substantially in the longitudinal direction of the molecule are condensed. AFI single crystal zeolite. Claim 1, wherein the AFI monocrystalline zeolite polynuclear aromatic hydrocarbons linear shape benzene ring has 2-5 Kochijimiwa is contained at a high density. The AFI single crystal zeolite according to claim 1 or 2, wherein the polynuclear aromatic hydrocarbon having a linear shape in which 2 to 5 benzene rings are condensed is 10 ¹² / cm ² or more in the zeolite. The AFI single molecule according to any one of claims 1 to 3, wherein the linear polynuclear aromatic hydrocarbon molecule having 2 to 5 benzene rings condensed is a polynuclear aromatic hydrocarbon molecule selected from naphthalene, anthracene, and pentacene. Crystalline zeolite. Benzene ring AFI monocrystalline zeolite is characterized by contacting the polynuclear aromatic hydrocarbons 2-5 Kochijimiwa the linear configuration, substantially molecule to the long axis of the molecules are arranged one-dimensionally A method for producing an AFI single crystal zeolite including a linear aggregate of polynuclear aromatic hydrocarbons having 2 to 5 condensed benzene rings. The method for producing a single crystal zeolite according to claim 5, wherein the AFI single crystal zeolite and a polynuclear aromatic hydrocarbon having a linear shape in which 2 to 5 benzene rings are condensed are vacuum-sealed in a container and heated.