JP4593157B2 - Refractive index conversion material - Google Patents

Description

The present invention relates to a refractive index conversion material comprising a cyclodextrin derivative having a norbornadiene structure.

Norbornadiene (hereinafter also referred to as “NBD”) undergoes photovalence isomerization to a quadricyclane having a low polarizability (hereinafter also referred to as “QC”) by irradiation with ultraviolet rays, A compound having an NBD structure is a light-heat energy conversion storage material that converts light energy into heat energy and accumulates it because it has the property of isomerizing to NBD with heat dissipation by contact and irradiation with light of a short wavelength. (See Non-Patent Document 1 and Non-Patent Document 2).
In addition, a compound having an NBD structure has a different refractive index from that of a compound having an isomerized QC structure, that is, has a characteristic in which the refractive index changes upon irradiation with light. Therefore, the compound having an NBD structure is used, for example, in an optical storage element or an optical switch system. Application to a refractive index conversion material is expected (see Non-Patent Document 3).

It is important that such a light-heat energy conversion storage material and a refractive index conversion material can be easily formed into a film. Conventionally, various polymers having an NBD structure introduced as compounds having an NBD structure that can be formed into a film have been proposed (see Non-Patent Document 4).
However, the conventional polymer with the NBD structure introduced has a refractive index change amount of about 0.01 or less due to light irradiation, and the refractive index change amount is not large.

  Thus, the present inventors have a large amount of change in refractive index and a large amount of heat storage by light irradiation, and can be easily formed into a film, which is useful as a light-heat energy conversion storage material and a refractive index conversion material. As a compound, a calixarene derivative in which an NBD structure is introduced into a hydroxyl group and a cyclodextrin derivative in which an NBD structure is introduced into a primary hydroxyl group have been proposed (see Patent Document 1). It has been found that an NBD structure can be introduced into other hydroxyl groups, and the present invention has been completed.

T. Nishikubo et al., Macromolecules, 22, 8 (1989) T. Nishikubo et al., Macromolecules, 31, 2789 (1998) K. Kinoshita et al., Appl. Lett., 70, 2940 (1997) C.D.Gutsche (ED), Calixarenes, Royal Soc. Chem. (1989) JP 2003-306470 A

An object of the present invention is to provide a refractive index conversion material that changes its refractive index by light irradiation, has a large amount of change in refractive index, and can be easily formed into a film .

Refractive index conversion material of the present invention is a cyclodextrin derivative represented by the following general formula (1), and characterized in that the etherification rate to the total hydroxyl groups in the cyclodextrin is made of cyclodextrin derivative is 60% or more To do.

[In General formula (1), R < ¹ >, R < ² > and R < ³ > show the group represented by a hydrogen atom or following formula (a) each independently, and m is an integer of 6-9. ]

By the cyclodextrin derivative, a rotaxane represented by the following general formula (2) is obtained.

[In General Formula (2), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a group represented by the above formula (a), and X is represented by —CH ₂ CH ₂ O—. A polymer chain composed of repeating units, m is an integer of 6 to 9, and k is an integer of 10 to 40. ]

The cyclodextrin derivative constituting the refractive index conversion material of the present invention has a large number of norbornadiene structures in one molecule and has an etherification rate of 60% or more with respect to all hydroxyl groups in the cyclodextrin. And the amount of change in the refractive index is extremely large, and the film can be formed easily .

Hereinafter, embodiments of the present invention will be described in detail.
[Cyclodextrin derivative]
The cyclodextrin derivative according to the present invention is a compound represented by the above general formula (1), which has a etherification rate of 60% or more, preferably 70% or more with respect to all hydroxyl groups in the cyclodextrin (hereinafter referred to as “cyclodextrin derivative”). , "Specific cyclodextrin derivative").
In the general formula (1), R ¹ , R ² and R ³ are each independently a hydrogen atom or a group represented by the above formula (a), and 60% of the total of R ¹ , R ² and R ³ The above is the group represented by the above formula (a). Moreover, m which shows the number of pyranose rings is an integer of 6-9.
Further, ethers Karitsu to total hydroxyl groups in cyclodextrin, in ¹ H-NMR spectrum, the signals of the methine protons of 4.84ppm based on the acetal of cyclodextrin as a reference, based on the olefin site of NBD 6.84-7. It can be determined from the integrated intensity ratio of the signal of 03 ppm methine proton.

This specific cyclodextrin derivative can be produced as follows.
First, 3-phenyl-2,5-norbornadiene-2-carboxylic acid and 1-bromo-2-chloroethane are reacted in an appropriate solvent to give 3-phenyl-2,5-norbornadiene-2-carboxylic acid. Carboxychloroethyl (hereinafter referred to as “specific norbornadiene derivative”) is synthesized.
In the reaction step for obtaining this specific norbornadiene derivative (hereinafter referred to as “reaction step (a-1)”), dimethyl sulfoxide, dimethylformamide, dioxane or the like can be used as a solvent.
The proportion of 3-phenyl-2,5-norbornadiene-2-carboxylic acid and 1-bromo-2-chloroethane used is 1-bromo with respect to 1 mol of 3-phenyl-2,5-norbornadiene-2-carboxylic acid. It is preferable that 2-chloroethane is 1.0-2.0 mol. Further, in the reaction step (a-1), it is preferable to add an alkaline agent such as 1,8-diazabicyclo [5.4.0] undecene-7, and the use ratio thereof is 3-phenyl-2, It is 1.0-2.0 mol with respect to 1 mol of 5-norbornadiene-2-carboxylic acid.
Moreover, as reaction conditions in reaction process (a-1), reaction temperature is 60-80 degreeC, for example, and reaction time is 24 to 48 hours.

  Next, by reacting a cyclodextrin represented by the following general formula (3) (hereinafter also simply referred to as “cyclodextrin”) with a specific norbornadiene derivative in an appropriate solvent in the presence of a catalyst, A specific cyclodextrin derivative is synthesized.

〔一般式（３）において、ｍは６〜９の整数を示す。〕

[In General formula (3), m shows the integer of 6-9. ]

In the reaction step for obtaining this specific cyclodextrin derivative (hereinafter referred to as “reaction step (a-2)”), N-methyl-2-pyrrolidone, dimethylformamide, dioxane or the like is used as a solvent. Can do.
As the catalyst, tetrabutylammonium bromide, tetraphenylphosphonium bromide, or the like can be used. Moreover, the usage-amount of a catalyst is 0.03-0.15 mol with respect to 1 mol of all the hydroxyl groups in cyclodextrin.
Specific examples of the cyclodextrin include α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, and δ-cyclodextrin. These compounds can be used alone or in combination of two or more.
The use ratio of the cyclodextrin and the specific norbornadiene derivative is such that the specific norbornadiene derivative is 0.7 mol or more, preferably 0.7 to 2 mol, relative to 1 mol of all hydroxyl groups in the cyclodextrin.
Moreover, in reaction process (a-2), it is preferable to add alkaline agents, such as sodium hydride, for example, and the use ratio is 1.0-1.5 mol with respect to 1 mol of specific norbornadiene. .
Moreover, as reaction conditions in reaction process (a-2), reaction temperature is 40-80 degreeC, for example, and reaction time is 2-48 hours.

  The synthesis process of the specific cyclodextrin derivative is shown in the following reaction formula (i).

〔反応式（ｉ）において、Ｒ¹ 、Ｒ² およびＲ³ は、それぞれ独立して水素原子または上記式（ａ）で表される基を示し、ｍは６〜９の整数である。〕

[In Reaction Formula (i), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a group represented by the above formula (a), and m is an integer of 6 to 9. ]

Since the specific cyclodextrin derivative according to the present invention has a cyclodextrin skeleton, it can be easily formed into a film.
Specifically, a film can be formed by dissolving a specific cyclodextrin derivative in an appropriate solvent, coating the obtained solution on an appropriate support, and drying.
As a solvent for dissolving a specific cyclodextrin derivative, dimethylformamide, tetrahydrofuran, N-methylpyrrolidone, dimethylformaldehyde, chloroform, methylene chloride and the like can be used.

  Since the specific cyclodextrin derivative according to the present invention has a large number of NBD structures in one molecule, it has a characteristic that the refractive index is changed by receiving specific light such as ultraviolet rays, as will be apparent from Examples described later. In addition, since the amount of change in the refractive index is large and it has a cyclodextrin skeleton, it is possible to form a film easily. In addition, the specific cyclodextrin derivative according to the present invention has a property of converting light energy into heat energy and storing it, and has a large amount of heat storage. Therefore, the specific cyclodextrin derivative according to the present invention is extremely useful as a refractive index conversion material used for an optical storage element, an optical switch system, and the like, and is extremely useful as a light-heat energy conversion storage material.

[Rotaxane]
The rotaxane of the present invention is a rotaxane having a specific cyclodextrin derivative as a cyclic molecule (hereinafter referred to as “specific rotaxane”).
In this specific rotaxane, various chain polymers can be used as the axial molecule, but a chain polymer having dinitrophenyl groups bonded to both ends is preferred.
The number of specific cyclodextrin derivatives present in one specific rotaxane molecule is preferably 10 to 40.
The specific rotaxane preferably has a number average molecular weight of 15000 to 20000 as measured by gel permeation chromatography.
As a specific example preferable as a specific rotaxane, the rotaxane represented by the said General formula (2) can be mentioned.
In the above general formula (2), R ¹ , R ² and R ³ are each independently a hydrogen atom or a group represented by the above formula (a), and a total of 60 of R ¹ , R ² and R ³ % Or more is the group represented by the above formula (a). X is a polymer chain composed of repeating units represented by —CH ₂ CH ₂ O—. M which shows the number of a pyranose ring is an integer of 6-9. K which shows the number of specific cyclodextrins is 10-40.

Such a specific rotaxane can be produced as follows.
First, an intermediate composed of a rotaxane having a cyclodextrin represented by the general formula (3) as a cyclic molecule is synthesized.
The method of synthesizing this intermediate differs depending on the type of chain polymer forming the axial molecule, but an example of synthesizing an intermediate having an axial molecule in the rotaxane represented by the general formula (2) will be given. It is as follows.
A polyethylene glycol having 3-aminopropyl groups at both ends is prepared, the polyethylene glycol and cyclodextrin are dissolved in an appropriate solvent, and the resulting solution is stirred by, for example, ultrasonic waves, whereby a pseudo A rotaxane is prepared.
Here, distilled water can be mentioned as a solvent used for preparation of pseudorotaxane.
As the cyclodextrin, specifically, α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, and δ-cyclodextrin are used. These compounds can be used alone or in combination of two or more.
The ratio of polyethylene glycol and cyclodextrin used is selected according to the number of specific cyclodextrin derivatives present in one specific rotaxane molecule to be produced. For example, 1 mol of polyethylene glycol (in terms of number average molecular weight) ) To 10 to 40 mol of cyclodextrin.
The pseudorotaxane is preferably prepared at a temperature of 15 to 40 ° C.
Next, by reacting the obtained pseudorotaxane and 2,4-dinitrofluorobenzene in an appropriate solvent, an axial molecule having dinitrophenyl groups bonded to both ends and a cyclic molecule composed of cyclodextrin are obtained. An intermediate comprising rotaxane is obtained.
Here, examples of the solvent used for the reaction of pseudorotaxane and 2,4-dinitrofluorobenzene include dimethylformamide and dimethylacetamide.
Moreover, the use ratio of pseudorotaxane and 2,4-dinitrofluorobenzene is, for example, 90 to 100 mol of 2,4-dinitrofluorobenzene with respect to 1 mol of pseudorotaxane (in terms of number average molecular weight).
The reaction conditions of pseudorotaxane and 2,4-dinitrofluorobenzene are, for example, a reaction temperature of 25 to 40 ° C. and a reaction time of 2 to 24 hours.

A specific rotaxane is synthesized by reacting the thus synthesized intermediate with a specific norbornadiene derivative.
In the reaction step for obtaining this specific rotaxane, N-methyl-2-pyrrolidone, dimethylformamide, dioxane or the like can be used as a solvent.
As the catalyst, tetrabutylammonium bromide, tetraphenylphosphonium bromide, or the like can be used. Moreover, the usage-amount of a catalyst is 0.03-0.15 mol with respect to 1 mol of all the hydroxyl groups in the cyclodextrin which exists in an intermediate body.
The use ratio of the intermediate and the specific norbornadiene derivative is such that the specific norbornadiene derivative is 0.7 mol or more with respect to 1 mol of all hydroxyl groups in the cyclodextrin present in the intermediate, preferably 0.7 to 2 mol. It is said.
Moreover, in this reaction process, it is preferable to add alkaline agents, such as sodium hydride, for example, and the usage-amount is 1.0-2.0 mol with respect to 1 mol of specific norbornadiene.
Moreover, as reaction conditions in this reaction process, reaction temperature is 40-80 degreeC, for example, and reaction time is 4 to 48 hours.

  Since the specific rotaxane according to the present invention has a specific cyclodextrin as a cyclic molecule, the specific rotaxane has a characteristic that the refractive index changes by receiving specific light such as ultraviolet rays, and the amount of change in the refractive index is large. It has the property of converting light energy into heat energy and storing it, has a large amount of heat storage, and can be easily formed into a film. Therefore, the specific rotaxane according to the present invention is extremely useful as a refractive index conversion material used for an optical storage element, an optical switch system, and the like, and is extremely useful as a light-heat energy conversion storage material.

  Specific examples of the present invention will be described below, but the present invention is not limited to these examples.

In the following examples, the following materials and solvents were used.
(1) As tetrabutyl-n-ammonium bromide (hereinafter referred to as “TBAB”), a commercially available product recrystallized twice using dehydrated ethyl acetate was used.
(2) As 3-phenyl-2,5-norbornadiene-2-carboxylic acid (hereinafter referred to as “PNC”), a commercially available product is recrystallized once using a mixed solvent of ethyl acetate / n-hexane. It was used.
(3) As α-cyclodextrin (hereinafter referred to as “α-CD”), a commercially available product was recrystallized twice using distilled water.
(4) As β-cyclodextrin (hereinafter referred to as “β-CD”), a commercially available product recrystallized twice using distilled water was used.
(5) As γ-cyclodextrin (hereinafter referred to as “γ-CD”), a commercially available product was recrystallized twice using distilled water.
(6) As 1-bromo-2-chloroethane (hereinafter referred to as “BCE”), a commercial product obtained by distillation purification using calcium chloride (desiccant) was used.
(7) As N-methyl-2-pyrrolidone (hereinafter referred to as “NMP”), a commercial product obtained by distillation purification using calcium hydride (desiccant) was used.
(8) As dimethyl sulfoxide (hereinafter referred to as “DMSO”), a commercially available product obtained by distillation purification using calcium hydride (desiccant) was used.
(9) As dimethylformamide (hereinafter referred to as “DMF”), a commercial product obtained by distillation purification using calcium hydride (desiccant) was used.
(10) As 1,8-diazabicyclo [5.4.0] undecene-7 (hereinafter referred to as “DBU”), a commercial product obtained by distillation purification using calcium hydride (desiccant) is used. did.
(11) As polyethylene glycol having a 3-aminopropyl group at both ends (hereinafter referred to as “PEG”), a commercially available product having a number average molecular weight of 1500 was used as it was.
(12) As 2,4-dinitrofluorobenzene, cyclohexanone and sodium hydride, commercially available products were used as they were.

Moreover, the following were used as a measuring apparatus.
(1) Infrared spectrophotometer: “FT / IR-420” manufactured by JASCO Corporation
(2) Ultraviolet spectrophotometer: “UV-2500PC” manufactured by Shimadzu Corporation
(3) ¹ H nuclear magnetic resonance apparatus: “JNM-α-500” (500 MHz) and “JNM-α-600” (600 MHz) manufactured by JEOL Ltd.
(4) Recycle preparative high performance liquid chromatography (hereinafter referred to as “preparative HPLC”: “HPLC-908 type” manufactured by Nihon Analytical Industries, Ltd. (column: JAIgel1HA-F and JAIgel1HA-A, developing solvent: chloroform)
(5) Ellipsometer: “L115B Ellipsometer” manufactured by Gardner

[Synthesis of specific norbornadiene derivatives]
To a mixture of 2.16 g (10 mmol) of PNC and 1.72 g (12 mmol) of DBU, 10 mL of DMSO was added and dissolved, and then 2.92 g (20 mmol) of BCE was added dropwise, and further reacted at room temperature for 4 hours.
After the reaction was completed, the reaction solution was diluted with ethyl acetate, and this diluted solution was washed with distilled water five times. Further, anhydrous magnesium sulfate was added to the ethyl acetate phase as a desiccant, followed by drying treatment. . Then, after filtering off the desiccant, the ethyl acetate phase was distilled off under reduced pressure, and then isolated and purified by silica gel column chromatography using a mixture of ethyl acetate and n-hexane (mixing ratio 1:10) as a developing solvent. As a result, 1.94 g of a yellow viscous liquid was obtained.
From the results of IR analysis and ¹ H-NMR analysis, the obtained product was 3-phenyl-2,5-norbornadiene-2-galoxychloroethyl (specific norbornadiene derivative) represented by the following formula (b): Was identified. The yield was 71%.

The results of IR analysis and ¹ H-NMR analysis of specific norbornadiene derivatives are shown below.
○ IR (film, cm ^-1 ):
1698 (νC = C ester),
1612 (νC = C NBD),
1594, 1491 (νC = C aromatic),
1180, 1021 (νC—O—C ester),
760 (νC-Cl)
○ ¹ H NMR (500 MHz, CDCl ₃ , TMS) δ (ppm):
1.98 (d, J = 6.0,1.0H, H a),
2.17 (d, J = 6.0, 1.0H, H ^a ′),
3.78 (t, J = 5.5, 2.0H, H ^j ),
4.00 (s, 1.0H, H ^b ),
4.29 (s, 1.0 H, H ^c ),
^{6.98~7.04 (m, 2.0H, H d} , H e),
^{7.34~7.56 (m, 5.0H, H g} , H f, H h)

<Example 1>
4 mL of NMP was added to a mixture of α-CD 0.05 g (0.05 mmol), TBAB 0.03 g (5 mol%) and sodium hydride 0.04 g (1.8 mmol), and the mixture was stirred at room temperature for 1 hour. Thereafter, 0.49 g (1.8 mmol) of a specific norbornadiene derivative was added and further reacted at 80 ° C. for 48 hours.
After the reaction was completed, the reaction solution was diluted with chloroform, washed once with 0.5N aqueous hydrochloric acid and 5 times with distilled water, and the organic phase was dried using anhydrous magnesium sulfate as a desiccant. The desiccant was filtered off, isolated and purified by preparative HPLC, and dried under reduced pressure at 60 ° C. for 24 hours to obtain 0.15 g of a brown powdered solid.
From the results of IR analysis and ¹ H-NMR analysis, the obtained product was a compound represented by the following formula (I), and the etherification rate with respect to all hydroxyl groups in α-CD was 89%. Identified. The yield was 45%. This product is designated as “cyclodextrin derivative (I)”. Moreover, the synthesis process of cyclodextrin derivative (I) is shown in the following reaction formula (I-1).

The results of IR analysis and ¹ H-NMR analysis of the cyclodextrin derivative (I) are shown below.
○ IR (film, cm ^-1 ):
3447 (νOH),
1704 (νC = C ester),
1615 (νC = C NBD),
1491, 1444 (νC = C aromatic),
1149, 1034 (νC—O—C)
○ ¹ H NMR (500 MHz, DMSO-d ₆ ) δ (ppm):
^{1.94~2.14 (m, 2.00H, H 9} ),
^{3.15~4.75 (m, 6.99H, H 1} , H 2, H 3, H 4, H 5, H 6, H 7, H 8, H 10, H 11),
5.40 to 6.05 (m, 0.12H, OH in CD),
^{6.94~7.42 (m, 7.00H, H 12} , H 13, H 14, H 15, H 16)

<Example 2>
4 mL of NMP was added to a mixture of β-CD 0.06 g (0.05 mmol), TBAB 0.04 g (5 mol%) and sodium hydride 0.05 g (2.1 mmol), and the mixture was stirred at room temperature for 1 hour. Thereafter, 0.59 g (2.1 mmol) of a specific norbornadiene derivative was added and further reacted at 80 ° C. for 48 hours.
After the reaction was completed, the reaction solution was diluted with chloroform, washed once with 0.5N aqueous hydrochloric acid and 5 times with distilled water, and the organic phase was dried using anhydrous magnesium sulfate as a desiccant. The desiccant was filtered off, isolated and purified by preparative HPLC, and dried under reduced pressure at 60 ° C. for 24 hours to obtain 0.15 g of a brown powdered solid.
From the results of IR analysis and ¹ H-NMR analysis, the obtained product was a compound represented by the following formula (II), and the etherification ratio for all hydroxyl groups in β-CD was 87%. Identified. The yield was 44%. This product is referred to as “cyclodextrin derivative (II)”. Further, the synthesis step of the cyclodextrin derivative (II) is shown in the following reaction formula (II-1).

The results of IR analysis and ¹ H-NMR analysis of the cyclodextrin derivative (II) are shown below.
○ IR (film, cm ^-1 ):
3423 (νOH),
1699 (νC = C ester),
1615 (νC = C NBD),
1491, 1444 (νC = C aromatic),
1149, 1033 (νC—O—C)
○ ¹ H NMR (500 MHz, DMSO-d ₆ ) δ (ppm):
^{1.92~2.13 (m, 2.00H, H 9} ),
^{3.15~4.82 (m, 8.85H, H 1} , H 2, H 3, H 4, H 5, H 6, H 7, H 8, H 10, H 11),
5.58-5.88 (m, 0.14H, OH in CD),
^{6.96~7.49 (m, 7.00H, H 12} , H 13, H 14, H 15, H 16)

<Example 3>
To a mixture of γ-CD 0.07 g (0.05 mmol), TBAB 0.04 g (5 mol%) and sodium hydride 0.06 g (2.4 mmol), 4 mL of NMP was added and stirred at room temperature for 1 hour. Thereafter, 0.66 g (2.4 mmol) of a specific norbornadiene derivative was added, and the mixture was further reacted at 80 ° C. for 48 hours.
After the reaction was completed, the reaction solution was diluted with chloroform, washed once with 0.5N aqueous hydrochloric acid and 5 times with distilled water, and the organic phase was dried using anhydrous magnesium sulfate as a desiccant. The desiccant was filtered off, isolated and purified by preparative HPLC, and dried under reduced pressure at 60 ° C. for 24 hours to obtain 0.11 g of a brown powdered solid.
From the results of IR analysis and ¹ H-NMR analysis, the product obtained was a compound represented by the following formula (III), and the etherification rate with respect to all hydroxyl groups in γ-CD was 84%. Identified. The yield was 35%. This product is referred to as “cyclodextrin derivative (III)”. Moreover, the synthesis process of cyclodextrin derivative (III) is shown in the following reaction formula (III-1).

The results of IR analysis and ¹ H-NMR analysis of the cyclodextrin derivative (III) are shown below.
○ IR (film, cm ^-1 ):
3414 (νOH),
1701 (νC = C ester),
1615 (νC = C NBD),
1491, 1444 (νC = C aromatic),
1149, 1033 (νC—O—C)
○ ¹ H NMR (500 MHz, DMSO-d ₆ ) δ (ppm):
^{1.96~2.10 (m, 2.00H, H 9} ),
^{3.15~4.75 (m, 9.26H, H 1} , H 2, H 3, H 4, H 5, H 6, H 7, H 8, H 10, H 11,),
5.58-5.88 (m, 0.18H, OH in CD),
^{6.94~7.42 (m, 7.00H, H 12} , H 13, H 14, H 15, H 16)

<Example 4>
To a mixture of β-CD 0.23 g (0.2 mmol), TBAB 0.06 g (5 mol%) and sodium hydride 0.09 g (3.0 mmol), 6 mL of NMP was added and stirred at room temperature for 1 hour. Thereafter, 0.83 g (3.0 mmol) of a specific norbornadiene derivative was added, and further reacted at 80 ° C. for 48 hours.
After completion of the reaction, the reaction solution was added dropwise to distilled water, and the precipitate was filtered off, followed by reprecipitation purification twice using tetrahydrofuran as a good solvent and diethyl ether as a poor solvent. By drying under reduced pressure for a period of time, 0.30 g of a brown powder solid was obtained.
From the results of IR analysis and ¹ H-NMR analysis, the obtained product was a compound represented by the following formula (IV), and the etherification ratio for all hydroxyl groups in β-CD was 62%. Identified. The yield was 35%. This product is designated as “cyclodextrin derivative (IV)”.

The results of IR analysis and ¹ H-NMR analysis of the cyclodextrin derivative (IV) are shown below.
○ IR (film, cm ^-1 ):
3377 (νOH),
1695 (νC = C ester),
1606 (νC = C NBD),
1594, 1491 (νC = C aromatic),
1153, 1032 (νC—O—C ester)
○ ¹ H NMR (500 MHz, DMSO-d ₆ ) δ (ppm):
1.84 to 2.23 (m, 2.0H, CH ₂ in NBD),
^{3.29~4.75 (m, 10.9H, H a} , H b, H c, H d, H f, H g, H h, CH in NBD, H 2 O),
^{4.80~4.84 (m, 0.66H, H e} ),
5.58-5.88 (m, 0.81H, OH in CD),
6.84 to 7.03 (m, 2.0H, CH in NBD),
7.34-7.47 (m, 5.0H, aromatic)

<Reference Example 1>
6 mL of NMP was added to a mixture of α-CD 0.29 g (0.3 mmol), TBAB 0.04 g (5 mol%) and sodium hydride 0.07 g (2.7 mmol), and the mixture was stirred at room temperature for 1 hour. Thereafter, 0.74 g (2.7 mmol) of a specific norbornadiene derivative was added, and the mixture was further reacted at 50 ° C. for 48 hours.
After completion of the reaction, the reaction solution was added dropwise to distilled water, and the precipitate was filtered off, followed by reprecipitation purification twice using tetrahydrofuran as a good solvent and diethyl ether as a poor solvent. By drying under reduced pressure for a period of time, 0.14 g of a brown powdered solid was obtained.
From the results of IR analysis and ¹ H-NMR analysis, the product obtained was a compound represented by the following formula (V), and the etherification rate for all hydroxyl groups in α-CD was 35%. Identified. The yield was 20%. This product is designated as “cyclodextrin derivative (V)”.

The results of IR analysis and ¹ H-NMR analysis of the cyclodextrin derivative (V) are shown below.
○ IR (film, cm ^-1 ):
3393 (νOH),
1696 (νC = C ester),
1615 (νC = C NBD),
1594, 1491 (νC = C aromatic),
1331, 1034 (νC—O—C ester),
1151, 1034 (νC-O-C ether)
○ ¹ H NMR (500 MHz, DMSO-d ₆ ) δ (ppm):
1.84 to 2.23 (m, 2.0H, CH ₂ in NBD),
^{3.29~4.75 (m, 19.3H, H a} , H b, H c, H d, H f, H g, H h, CH in NBD, H 2 O),
^{4.80~4.84 (m, 1.0H, H e} ),
5.58-5.88 (m, 1.95H, OH in CD),
6.84 to 7.03 (m, 2.0H, CH in NBD),
7.34-7.47 (m, 5.0H, aromatic)

<Reference Example 2>
To a mixture of β-CD 0.34 g (0.3 mmol), TBAB 0.04 g (5 mol%) and sodium hydride 0.08 g (3.1 mmol), 6 mL of NMP was added and stirred at room temperature for 1 hour. Thereafter, 0.85 g (3.1 mmol) of a specific norbornadiene derivative was added, and the mixture was further reacted at 50 ° C. for 48 hours.
After completion of the reaction, the reaction solution was added dropwise to distilled water, and the precipitate was filtered off, followed by reprecipitation purification twice using tetrahydrofuran as a good solvent and diethyl ether as a poor solvent. By drying under reduced pressure for a period of time, 0.24 g of a brown powder solid was obtained.
From the results of IR analysis and ¹ H-NMR analysis, the obtained product was a compound represented by the following formula (VI), and the etherification ratio of β-CD with respect to all hydroxyl groups was 33%. Identified. The yield was 27%. This product is designated as “cyclodextrin derivative (VI)”.

The results of IR analysis and ¹ H-NMR analysis of the cyclodextrin derivative (VI) are shown below.
○ IR (film, cm ^-1 ):
3394 (νOH),
1698 (νC = C ester),
1615 (νC = C NBD),
1593, 1491 (νC = C aromatic),
1333, 1033 (νC—O—C ester),
1151, 1078 (νC-O-C ether)
○ ¹ H NMR (500 MHz, DMSO-d ₆ ) δ (ppm):
1.84 to 2.23 (m, 2.0H, CH ₂ in NBD),
^{3.29~4.75 (m, 19.3H, H a} , H b, H c, H d, H f, H g, H h, CH in NBD, H 2 O),
^{4.80~4.84 (m, 1.0H, H e} ),
5.58-5.88 (m, 1.95H, OH in CD),
6.84 to 7.03 (m, 2.0H, CH in NBD),
7.34-7.47 (m, 5.0H, aromatic)

<Reference Example 3>
To a mixture of γ-CD 0.39 g (0.3 mmol), TBAB 0.06 g (5 mol%) and sodium hydride 0.09 g (3.6 mmol), 6 mL of NMP was added and stirred at room temperature for 1 hour. Thereafter, 0.99 g (3.6 mmol) of a specific norbornadiene derivative was added, and the mixture was further reacted at 50 ° C. for 48 hours.
After completion of the reaction, the reaction solution was added dropwise to distilled water, and the precipitate was filtered off, followed by reprecipitation purification twice using tetrahydrofuran as a good solvent and diethyl ether as a poor solvent. By drying under reduced pressure for a period of time, 0.14 g of a brown powdered solid was obtained.
From the results of IR analysis and ¹ H-NMR analysis, the obtained product was a compound represented by the following formula (VII), and the etherification ratio for all hydroxyl groups in γ-CD was 36%. Identified. The yield was 15%. This product is designated as “cyclodextrin derivative (VII)”.

The results of IR analysis and ¹ H-NMR analysis of cyclodextrin derivative (VII) are shown below.
○ IR (film, cm ^-1 ):
3394 (νOH),
1711 (νC = C ester),
1615 (νC = C NBD),
1596, 1492 (νC = C aromatic),
1331, 1030 (νC—O—C ester),
1151, 1080 (νC-O-C ether)
○ ¹ H NMR (500 MHz, DMSO-d ₆ ) δ (ppm):
1.84 to 2.23 (m, 2.0H, CH ₂ in NBD),
^{3.29~4.75 (m, 10.9H, H a} , H b, H c, H d, H f, H g, H h, CH in NBD, H 2 O),
^{4.80~4.84 (m, 1.0H, H e} ),
5.58-5.88 (m, 1.75H, OH in CD),
6.84 to 7.03 (m, 2.0H, CH in NBD),
7.34-7.47 (m, 5.0H, aromatic)

  In Examples 1 to 4 and Reference Examples 1 to 3, the type of cyclodextrin used, the molar ratio of a specific norbornadiene derivative to all hydroxyl groups in the cyclodextrin (hereinafter referred to as “NBD / OH”), the reaction temperature, and Table 1 shows the etherification rate of all hydroxyl groups in cyclodextrin.

[Characteristics of cyclodextrin derivatives]
(1) Refractive index change:
Each of cyclodextrin derivative (I) to cyclodextrin derivative (IV) according to Examples 1 to 4 and cyclodextrin derivative (V) to cyclodextrin derivative (VII) according to Reference Examples 1 to 3 was dissolved in cyclohexanone to obtain The obtained solution was applied to a silicon wafer by a spin coater and dried to form a thin film having a thickness of about 1.0 mm. The obtained thin film was irradiated with light using a 500 W xenon lamp for 30 minutes, and the refractive index before and after light irradiation was measured with a laser beam having a wavelength of 632.8 nm using an ellipsometer. The amount of change was determined.
The results are shown in Table 2.

  As is apparent from the results in Table 2, each of the cyclodextrin derivatives (I) to cyclodextrin derivatives (IV) according to Examples 1 to 4 has a characteristic that the refractive index changes by light irradiation, The amount of change in the refractive index was large, and it was confirmed that it was useful as a refractive index conversion material.

(2) Photoreactive characteristics:
Each of cyclodextrin derivative (I) to cyclodextrin derivative (III) according to Examples 1 to 3 and cyclodextrin derivative (V) to cyclodextrin derivative (VII) according to Reference Examples 1 to 3 was dissolved in tetrahydrofuran to obtain Each of the obtained solutions was applied to the inner wall surface of the quartz cell and dried under reduced pressure at room temperature for 2 hours to form a thin film. 1.20 mW using a 500 W xenon lamp “UXL-500D-O” (manufactured by USHIO INC.) And a heat ray cut filter “HA50” (manufactured by HOYA) on the thin film formed in the quartz cell. The light irradiation treatment was performed while changing the light irradiation time under the conditions of / cm ² (313 nm), and the change in the absorbance of ultraviolet rays in the thin film was measured with an ultraviolet spectrophotometer. The results are shown in FIG. 1 (cyclodextrin derivative (I), FIG. 2 (cyclodextrin derivative (II)), FIG. 3 (cyclodextrin derivative (III)), FIG. 4 (cyclodextrin derivative (V)), FIG. Dextrin derivative (VI)) and FIG. 6 (cyclodextrin derivative (VII)).

From the result of FIG. 1, in the thin film made of cyclodextrin derivative (I), it was confirmed that the absorption of ultraviolet rays having a maximum absorption wavelength of 293 nm due to the NBD structure decreases with the passage of light irradiation time. It is understood that the photoabsorptive reaction from the NBD structure to the QC structure corresponding to the NBD structure proceeds without any side reaction by confirming the isosbestic points at the wavelength of 236 nm and the wavelength of 252 nm. In addition, it was confirmed that the photoisomerization reaction was completed in about 5 minutes.
From the result of FIG. 2, in the thin film made of cyclodextrin derivative (II), it is confirmed that the absorption of ultraviolet light having a maximum absorption wavelength of 296 nm based on the NBD structure decreases with the passage of light irradiation time. The fact that the isoabsorption point was confirmed at 237 nm and wavelength 253 nm indicates that the photoisomerization reaction from the NBD structure to the corresponding QC structure proceeds without causing side reactions. In addition, it was confirmed that the photoisomerization reaction was completed in about 7 minutes.
From the result of FIG. 3, in the thin film made of cyclodextrin derivative (III), it is confirmed that the absorption of ultraviolet rays having a maximum absorption wavelength of 291 nm based on the NBD structure decreases with the passage of light irradiation time. It is understood that the photoabsorption reaction from the NBD structure to the QC structure corresponding to the NBD structure proceeds without any side reaction by confirming the isosbestic points at 236 nm and the wavelength of 253 nm. It was also confirmed that the photoisomerization reaction was completed in about 10 minutes.
From the result of FIG. 4, in the thin film made of cyclodextrin derivative (V), it is confirmed that the absorption of ultraviolet rays having a maximum absorption wavelength of 295 nm based on the NBD structure decreases with the passage of light irradiation time. It is understood from the fact that the isosbestic points are confirmed at 237 nm and 251 nm, the photoisomerization reaction from the NBD structure to the corresponding QC structure proceeds without causing side reactions. In addition, it was confirmed that the photoisomerization reaction was completed in about 5 minutes.
From the result of FIG. 5, in the thin film made of cyclodextrin derivative (VI), it is confirmed that the absorption of ultraviolet rays having a maximum absorption wavelength of 297 nm based on the NBD structure decreases with the passage of light irradiation time. By confirming the isosbestic points at 236 nm and 254 nm, it is understood that the photoisomerization reaction from the NBD structure to the corresponding QC structure proceeds without causing side reactions. In addition, it was confirmed that the photoisomerization reaction was completed in about 5 minutes.
From the result of FIG. 6, in the thin film made of cyclodextrin derivative (VI), it is confirmed that the absorption of ultraviolet rays having a maximum absorption wavelength of 285 nm based on the NBD structure decreases with the passage of light irradiation time. By confirming the isosbestic points at 235 nm and 252 nm, it is understood that the photoisomerization reaction from the NBD structure to the corresponding QC structure proceeds without causing side reactions. It was also confirmed that the photoisomerization reaction was completed in about 10 minutes.

Moreover, the isomerization reaction rates in the thin film states of cyclodextrin derivative (I) to cyclodextrin derivative (III) and cyclodextrin derivative (V) to cyclodextrin derivative (VII) were plotted in a first-order rate equation.
Further, each of cyclodextrin derivative (I) to cyclodextrin derivative (III) and cyclodextrin derivative (V) to cyclodextrin derivative (VII) is adjusted so that the NBD residue concentration is 1 × 10 ⁻⁴ mol / L. Dissolved in tetrahydrofuran. Each of the obtained solutions was put in a quartz cell, and a 500 W xenon lamp and a heat ray cut filter “HA50” (manufactured by HOYA) were used for this solution under the condition of 1.20 mW / cm ² (313 nm). In addition to performing light irradiation treatment while changing the light irradiation time, the change in the absorbance of ultraviolet light in the solution is measured by ultraviolet spectrophotometry, and the isomerization reaction rate of each of these cyclodextrins in the solution state is expressed by a first-order rate equation. Plotted. Here, the isomerization reaction rate was determined from the change in absorbance at the maximum absorption wavelength.
FIG. 7 (cyclodextrin derivative (I)), FIG. 8 (cyclodextrin derivative (II)), FIG. 9 (cyclodextrin derivative (III)), FIG. 10 (cyclodextrin derivative (V)), FIG. 11 (cyclodextrin derivative (VI)) and FIG. 12 (cyclodextrin derivative (VII)).
From the results of FIGS. 7 to 12, the photoisomerization reaction in each of cyclodextrin derivative (I) to cyclodextrin derivative (III) and cyclodextrin derivative (V) to cyclodextrin derivative (VII) It is understood that in both cases, the progression is in the first order.

It is a figure which shows the change of the light absorbency of the ultraviolet-ray in the thin film state of the cyclodextrin derivative which concerns on Example 1. FIG. It is a figure which shows the change of the light absorbency of the ultraviolet-ray in the thin film state of the cyclodextrin derivative which concerns on Example 2. FIG. It is a figure which shows the change of the light absorbency of the ultraviolet-ray in the thin film state of the cyclodextrin derivative which concerns on Example 3. FIG. It is a figure which shows the change of the light absorbency of the ultraviolet-ray in the thin film state of the cyclodextrin derivative which concerns on the reference example 1. FIG. It is a figure which shows the change of the light absorbency of the ultraviolet-ray in the thin film state of the cyclodextrin derivative which concerns on the reference example 2. FIG. It is a figure which shows the change of the light absorbency of the ultraviolet-ray in the thin film state of the cyclodextrin derivative which concerns on the reference example 3. FIG. It is the figure which plotted the isomerization reaction rate in the thin film state and solution state of the cyclodextrin derivative which concerns on Example 1 to the primary rate equation. It is the figure which plotted the isomerization reaction rate in the thin film state and solution state of the cyclodextrin derivative which concerns on Example 2 to the primary rate equation. It is the figure which plotted the isomerization reaction rate in the thin film state and solution state of the cyclodextrin derivative which concerns on Example 3 to the primary rate equation. It is the figure which plotted the isomerization reaction rate in the thin film state and solution state of the cyclodextrin derivative which concerns on the reference example 1 to the primary rate equation. It is the figure which plotted the isomerization reaction rate in the thin film state and solution state of the cyclodextrin derivative which concerns on the reference example 2 to the primary rate equation. It is the figure which plotted the isomerization reaction rate in the thin film state and solution state of the cyclodextrin derivative which concerns on Example 3 to the primary rate equation.

Claims (1)

A refractive index conversion material comprising a cyclodextrin derivative represented by the following general formula (1), wherein the cyclodextrin derivative has an etherification ratio of 60% or more with respect to all hydroxyl groups in the cyclodextrin.

[In General formula (1), R < ¹ >, R < ² > and R < ³ > show the group represented by a hydrogen atom or following formula (a) each independently, and m is an integer of 6-9. ]

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