JPH0154283B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is applicable to catalysts for various chemical reactions, immobilized artificial oxygen, microcapsules for chemicals, especially pharmaceuticals, agricultural chemicals, insecticides, herbicides, etc., and fillers for gel chromatography. A new α used as
-Relating to a crystalline composite of zirconium phosphate and a cyclodextrin compound and a method for producing the same.

Conventional technology Conventionally, cyclodextrin-based compounds have been used for microencapsulation to stabilize chemically unstable substances, especially pharmaceuticals, pesticides, herbicides, etc., by utilizing their molecular inclusion ability and catalytic ability. It is used as a solubilizing agent for poorly soluble substances, a packing material for column chromatography, etc. It has also attracted attention as an oxygen model, and attempts are being made to introduce special functional groups to improve its functionality and use it as an artificial enzyme.

In order to improve the functionality of cyclodextrin, conventional methods have been to introduce functional groups into cyclodextrin or to make it into a polymer.

The inventor previously proposed that the chemical formula Zr(HPO ₄ ) ₂・H ₂ O
α-zirconium phosphate having a layered structure shown in mono-(6-β-aminoethylamino-6
-deoxy)-β-cyclodextrin when immersed in an aqueous solution of bicarbonate, a conversion reaction of about 29 Å
We have developed a crystalline composite with an interlayer distance of (Chemical Society of Japan 48th Autumn Annual Meeting Proceedings 1 2B12).

However, in order to increase the conversion rate of this conversion reaction,
When the concentration of the reaction solution was increased, the resulting complex rapidly became amorphous, and in the end, the production rate of this crystalline complex remained at a low rate. Furthermore, in this complex, the cyclodextrin molecules incorporated between the zirconium phosphate layers cover each other's cavities and are arranged close to the inorganic layer, so the guest molecules are enclosed within the structure. The structure was inconvenient for achieving high-level functions such as catalytic action.

OBJECTS OF THE INVENTION The present invention aims to overcome the drawbacks of the conventional crystalline composites, and its purpose is to provide a crystalline composite of zirconium phosphate-cyclodextrin compound suitable for molecular inclusion. .

Composition of the Invention As a result of further intensive research in order to achieve the above object, the inventor of the present invention found that the cause of the above disadvantages was due to the use of bicarbonate of mono-(6-β-aminoethylamino-6-deoxy)-β-cyclodextrin. This is because it was used;
Instead, we have found that by removing the bicarbonate content and making it into a base form, this drawback can be eliminated. The present invention was completed based on this knowledge.

The gist of the present invention is that α-zirconium phosphate has a layered structure represented by the chemical formula Zr(HPO ₄ ) ₂ H ₂ O, and mono-(6-β-aminoethylamino-6-deoxy)- A compound containing β-cyclodextrin and having a compositional formula Zr having an interlayer distance within a range of 35 to 37 Å
(HPO ₄ ) ₂ (CDen)x・yH ₂ O (where 0.1≦x≦
0.38, 0≦y≦10, CDen: the cyclodextrin).

Both the cyclodextrin compound and α-zirconium phosphate used in the present invention are compounds that have molecular inclusion ability. Molecular inclusion ability means that there is a cavity of an appropriate size inside a three-dimensional or two-dimensional structure formed by bonding atoms or molecules, and other molecules can be incorporated into the cavity to form a specific crystal structure. It has the ability to

For example, cyclodextrin, which is a cyclic polymer of D-glucose, has a cylindrical cavity in the center with a diameter of 5 to 8 Å and a depth of 8 Å, and has a catalytically active alcohol group in the side chain, and has inclusion ability and catalytic activity. He has the ability.

Further, α-zirconium phosphate shown in the above chemical formula has a layered structure and has inclusion ability. This α-
By introducing a cyclodextrin-based compound between the layers of zirconium phosphate to form a complex, it has two inclusion lattices, one layered and one cylindrical. It has improved properties as a filter material, and can also be useful as a microencapsulating agent for chemicals, especially pharmaceuticals, agricultural chemicals, insecticides, herbicides, etc., a packing material for gel chromatography, and as an enzyme model. It was.

This composite is obtained by soaking and holding α-zirconium phosphate powder in the aqueous solution of cyclodextrin for a certain period of time, and has the composition formula Zr
(HPO ₄ ) ₂ (CDen)x・yH ₂ O (where 0.1≦x≦
0.38, 0≦y≦10, CDen: the cyclodextrin).

For example, it can be produced by mixing 1 g of α-zirconium phosphate powder with an aqueous solution containing 1 mmol or more of the cyclodextrin and holding the mixture at 20 to 60° C. for 2 hours or more. In this case, in order to obtain the complex in high yield, the cyclodextrin should be at least 2 mmol per 1 g of α-zirconium phosphate powder, and the concentration of the aqueous solution should be 1 to 100 mM.
It is preferable to keep it at a certain level. There is no particular upper limit to the mixing ratio of the cyclodextrin, but if 1 mmol or more is mixed, the crystallinity of the resulting composite tends to decrease slightly, so the mixing ratio should be 2 mmol or more and 10 mmol or less. preferable.

In addition, the cyclodextrin to be used should be sufficiently purified by fractionating the crude reaction product with a CM-cellulose column and repeating the process of dissolving and concentrating several times using dilute ammonia water and pure water. is preferred.

The obtained complex was separated from the liquid and washed with water for 30 to 30 minutes.
Drying at 40°C for 12-24 hours yields a crystalline complex of zirconium phosphate-cyclodextrin compounds.

This crystalline composite has a microcomposite structure in which a cyclodextrin compound layer is incorporated between α-zirconium phosphate layers, and the interlayer distance is
It increases from 7.4 Å (anhydrous state) by 27.6 to 29.6 Å, which corresponds to the thickness of a bilayer of cyclodextrin compounds.

Considering the thickness of this bilayer, the cyclodextrin molecules incorporated between the layers are arranged so that the central axis of the cavity is parallel or nearly parallel to the zirconium phosphate layer. It can be seen that it forms Therefore, the structure between the layers makes it easy to package other guest molecules.

Effects of the Invention Since the composite of the present invention has the above-mentioned structure, (1) When it is used as a catalyst, it is easy to separate the products from conventional ones due to its solubility. However, since it is crystalline and the catalyst part is fixed and insolubilized, the product can be easily separated and continuous reactions can be carried out, and because it is combined with a layered lattice, it has high selectivity for the reaction. ,
Excellent as a catalyst or artificial enzyme.

(2) With cyclodextrin compounds alone, drug elution is relatively fast and the durability of drug efficacy is poor;
In the complex of the present invention, the drug is fixed in the cyclodextrin compound between the α-zirconium phosphate layers, so the drug does not come into direct contact with, for example, wet areas in the soil, suppressing its elution and increasing its efficacy. It lasts for a long time and is excellent as a microcapsule.

(3) Since the complex of the present invention has a separation effect due to the α-zirconium phosphate layer, it can exhibit excellent effects such as improved separation ability and becomes an excellent chromatography packing material.

Example 1 α-zirconium phosphate Zr (HPO ₄ ) ₂・H ₂ O0.05
g and mono-(6-β-aminoethylamino-6-
deoxy)-β-cyclodextrin (hereinafter referred to as
(abbreviated as CDen) was mixed with 4 ml of a 62.5 mM aqueous solution and shaken at 25°C for 14 days. After centrifuging the solid phase,
The composite was washed with water and dried at 40°C to obtain a composite.

The content of CDen and water in this composite is determined by the inorganic phase 1
They were 0.368 mol and 5.3 mol per mol, respectively.

Moreover, its X-ray diffraction pattern is as shown in FIG. 1A, indicating that it has been transformed into a crystalline composite with an interlayer distance of 35.6 Å. Furthermore, according to model calculations of the structure of the organic layer, this composite has a structure in which the central axis of the CDen molecule cavity is arranged in two molecular layers almost parallel to the zirconium phosphate layer.

For comparison, α-zirconium phosphate
0.05 g of Zr(HPO ₄ ) ₂ ·H ₂ O and 4 ml of CDen 1.38 mM aqueous solution were mixed and shaken at 25° C. for 14 days. After centrifuging the solid phase, it was washed with water and dried at 40°C.

Figure 1B shows the X-ray diffraction pattern of the obtained composite, and the contents of CDen and water in the composite are as follows:
They were 0.03 mol and 2.5 mol per mol, respectively.
The interlayer distance of the small amount of the composite produced could not be measured.

[Brief explanation of drawings]

The drawings are X-ray diffraction patterns of the crystalline composite of the present invention, A is the crystalline composite obtained in Example 1, B is
shows a comparative example of a composite with different amounts of α-zirconium phosphate and CDen.

Claims (1)

[Claims] 1. α-zirconium phosphate having a layered structure represented by the chemical formula Zr(HPO ₄ ) ₂ ·H ₂ O, and mono-(6-β-aminoethylamino-6-deoxy) between the layers. -A compound having the composition formula Zr in which β-cyclodextrin is present and having an interlayer distance within the range of 35 to 37 Å
(HPO ₄ ) ₂ (CDen)x・yH ₂ O (where 0.1≦x≦
0.38, 0≦y≦10, CDen: a crystalline composite of a zirconium phosphate-cyclodextrin compound. 2 α-Zirconium phosphate powder having a layered structure represented by the chemical formula Zr(HPO ₄ ) ₂ ·H ₂ O is mixed with 1 mmol or more of mono-(6-β-
Compositional formula Zr (HPO ₄ ) ₂ (CDen) x・yH ₂ O (where 0.1≦x≦0.38, 0≦y≦10, CDen: the cyclodextrin) A method for producing a crystalline composite of a zirconium phosphate-cyclodextrin compound.