JP3015543B2 - Photochromic compounds - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photofunctional material utilizing photochromism, and more particularly to a photochromic compound.

[0002]

2. Description of the Related Art Photochromism is a phenomenon in which a single chemical species reversibly forms two states A and B having different absorption spectra as shown below without changing the molecular weight by the action of light. . Many photochromic compounds have been synthesized so far. In particular, there have been many reports on spiropyran derivatives, such as those disclosed in JP-A-62-146979. When color multiplexing is performed using a photochromic compound, yellow color development is required from three primary colors.
However, in many of these, the colored body (hereinafter referred to as colored body) obtained by absorbing the B, that is, ultraviolet light, is red,
Blue or purple, and few yellow.

On the other hand, US Pat. No. 3,567,605 discloses that
Compounds that change from colorless to yellow or orange are indicated. However, these compounds have low temperatures (eg, -1).
(0 ° C. to 0 ° C.) only, and no color change near room temperature. Therefore, it was not suitable for practical use as a functional material .

[0004] In this manner, indicated photochromism at room temperature, the photochromic compound colored body is colored in yellow <br/> have little. For example, when trying to apply the photochromic compound in sunglasses, the color bodies is required to be thermally stable at room temperature, such compounds are desired. The photochromic reaction takes place at room temperature,
A compound that quickly returns to its original colorless body under heat and shade
Is desired .

[0005]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a novel photochromic compound which is colored to various colors including yellow by irradiating with ultraviolet light at room temperature .

[0006]

The photochromic compound of the present invention has the general formula

Embedded image [Where X is an oxygen atom, a sulfur atom or NR ⁷ (R
⁷ is a hydrogen atom alkyl group or an aryl group), R ¹ and R ² each independently represent a hydrogen atom, a methyl group, or a methoxy group, or a substituted or unsubstituted benzene ring is condensed with R ¹ and R ² are doing. R ³ , R ⁴
And / or a substituted or unsubstituted benzene ring is condensed at R ⁵ and R ⁶ . ).

Preferred compounds have the general formula

Embedded image (R ³ , R ⁴ , R ⁵ , and R ⁶ are the same as described above).

The following compounds can be given as specific examples of the photochromic compound of the present invention.

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Embedded image (In the formula, X, R ¹ and R ² are the same as described above.) Particularly preferred compounds include the following compounds.

[0009]

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The compounds of the present invention are well soluble in common organic solvents. Examples of the solvent include aliphatic solvents such as hexane and heptane, aromatic compounds such as benzene and toluene, halogen compounds such as dichloromethane, chloroform and carbon tetrachloride, and ether compounds such as ether and tetrahydrofuran (hereinafter referred to as THF). Esters such as ethyl acetate, ketones such as acetone and methyl ethyl ketone,
Examples thereof include nitriles such as acetonitrile and N, N-dimethylformamide.

The compound of the present invention can be prepared in a solvent as described above,
Shows photochromism at room temperature. That is, by irradiating the compound of the present invention with sunlight or ultraviolet light in the above-mentioned solvent, the compound is immediately colored and returns to an original colorless solution in a dark place. Specifically, the compound synthesized in Example 1 was irradiated with ultraviolet light, and the change in the absorption spectrum is shown in FIG.

The compound of the present invention is in a closed state of low polarity before irradiation with light, but has a high ionic polarity after irradiation with light, so that it is also effective as a photosensitive material.

Embedded image (Here, hν and hν ′ indicate light irradiation, and Δ indicates heating.)

The colored product obtained by irradiating the compound of the present invention with light quickly returns to the original colorless product at room temperature in a dark place . Therefore, it is effective as a component of a light control material such as sunglasses that is colored in sunlight and decolored when no light is applied.

In the compound of the present invention, the compound having a long-chain alkyl group is remarkably stable in a thin film due to the interaction with the alkyl group in a thin film. Therefore, it is also effective as one component of the optical recording material. In addition to these uses, the compounds of the present invention have a wide range of uses such as optical filters, display materials, masking materials, photometers, and decorative materials.

The method for synthesizing the compound of the present invention is described below.

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That is, a diol (c) is obtained by reacting a base such as n-butyllithium on the compound (a) and adding a salicylaldehyde derivative (b) thereto. At this time, the solvent to be used is not particularly limited as long as it is an inert solvent, but ether solvents such as ether and tetrahydrofuran are preferable. Next, a compound of the present invention represented by the formula (1) is obtained by adding a dehydration catalyst such as magnesium sulfate or sodium sulfate to the obtained diol (c). At this time, the reaction proceeds faster by coexisting an acid catalyst such as p-toluenesulfonic acid. However, heating without an acid catalyst promotes the reaction. The reaction temperature is not particularly limited, but is preferably from room temperature to about 200 ° C.

[0017]

EXAMPLES The present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples. (Example 1) 13aH-13 represented by the following formula
a-Methylbenzo [f] benzo [1] thieno [3,2-
b] Synthesis of chromene

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(1) Synthesis of 1- (3-methylbenzo [b] thiophen-2-yl-hydroxymethyl) -2-naphthol To a 50 ml three-necked flask were added 741 mg of 3-methylbenzo [b] thiophene and 5 ml of THF, and 0 ° C. Cool. 3.7 ml of 1.6N n-butyllithium was added dropwise thereto, and the mixture was stirred for 1 hour. Then, 2-hydroxy-1
-A solution of 344 mg of naphthaldehyde in 5 ml of THF was added dropwise and stirred for 3 hours. 10 ml of water and 10 ml of ether were added for extraction, and the organic layer was washed three times with 20 ml of water and concentrated. Purification by silica gel column chromatography (hexane / ethyl acetate = 3/1) gave the title compound as 1
50 ml were obtained. The structure was confirmed by NMR.

(2) Synthesis of 13aH-13a-methylbenzo [f] benzo [1] thieno [3,2-b] chromene 100 mg of the compound obtained in the above (1), 100 mg of magnesium sulfate and 10 ml of benzene were mixed with 50 ml of eggplant. Place in flask and heat at 60 ° C. for 5 hours. The mixture was filtered to remove magnesium sulfate, concentrated and purified by silica gel column chromatography (hexane / ethyl acetate = 3/1) to obtain 40 mg of the title compound. The structure was confirmed by NMR. FIG. 1 shows the absorption spectrum of the obtained compound in acetonitrile. After irradiation with ultraviolet light, it was colored yellow and returned to the spectrum 2 in FIG. 1, and when left in a dark place, returned to the spectrum 1 in FIG. 1, showing photochromism.

(Embodiment 2) 1 represented by the following formula
Synthesis of 3aH-13a-methylbenzo [h] benzo [1] thieno [3,2-b] chromene

Embedded image Instead of 2-hydroxy-1-naphthaldehyde used in Example 1 for 1-hydroxy-2-naphthaldehyde,
It synthesize | combines by the method according to Example 1.

(Embodiment 3) 1 represented by the following formula 15
Synthesis of 5aH-15a-methyldibenzo [f, h] benzo [1] thieno [3,2-b] chromene

Embedded image In place of the 2-hydroxy-1-naphthaldehyde used in Example 1 for 9-formyl-10-phenanthrol,
It synthesize | combines by the method according to Example 1.

(Embodiment 4) 1 represented by the following formula
Synthesis of 3aH-13a-methylbenzo [f] benzo [1] furo [3,2-b] chromene

Embedded image It synthesize | combines by the method according to Example 1 instead of 3-methylbenzo [b] thiophene used in Example 1 instead of 3-methyl-benzo [b] furan.

(Embodiment 5) 1 represented by the following formula
Synthesis of 3aH-13a-methylbenzo [h] benzo [1] furo [3,2-b] chromene

Embedded image In place of the 2-hydroxy-1-naphthaldehyde used in Example 4 for 1-hydroxy-2-naphthaldehyde,
It synthesize | combines by the method according to Example 1.

(Embodiment 6) 1 represented by the following formula
Synthesis of 5aH-15a-methyldibenzo [f, h] benzo [1] furo [3,2-b] chromene

Embedded image In place of the 2-hydroxy-1-naphthaldehyde used in Example 4 for 9-formyl-10-phenanthrol,
It synthesize | combines by the method according to Example 1.

Example 7 1 represented by the following formula:
Synthesis of 3aH-13a-methylbenzo [f] N-methylindolino [3,2-b] chromene

Embedded image The synthesis is carried out in the same manner as in Example 1 except that 3-methylbenzo [b] thiophene used in Example 1 is replaced with N-methylskatole.

(Embodiment 8) 1 represented by the following formula
Synthesis of 3aH-13a-methylbenzo [h] N-methylindolino [3,2-b] chromene

Embedded image In place of the 2-hydroxy-1-naphthaldehyde used in Example 7 for 1-hydroxy-2-naphthaldehyde,
It synthesize | combines by the method according to Example 1.

Example 9 1 represented by the following formula:
Synthesis of 5aH-15a-methyldibenzo [f, h] N-methylindolino [3,2-b] chromene

Embedded image In place of the 2-hydroxy-1-naphthaldehyde used in Example 4 for 9-formyl-10-phenanthrol,
It synthesize | combines by the method according to Example 1.

[0028]

The compound of the present invention is a novel photochromic compound, which is colored to various colors including yellow by irradiating ultraviolet light, and is left in a dark place or irradiated with visible light. The color fades and this change can be repeated . Thus, the compounds of the present invention are extremely useful as recording materials, copy materials, light control materials, photosensitive materials, display materials, masking materials or optical filters.

[Brief description of the drawings]

FIG. 1 shows the absorption spectrum of 13aH-13a-methylbenzo [f] benzo [1] thieno [3,2-b] chromene synthesized in Example 1.

[Explanation of symbols]

 1 Before UV light irradiation (solid line spectrum) 2 After UV light irradiation (dotted line spectrum)

Claims (2)

(57) [Claims] 1. A compound of the general formula [Where X is an oxygen atom, a sulfur atom or NR ⁷ (R
⁷ is a hydrogen atom, an alkyl group or an aryl group), R ¹
And R ² each independently represent a hydrogen atom, a methyl group, or a methoxy group, or a substituted or unsubstituted benzene ring is fused with R ¹ and R ² . Also, R ³ ,
A substituted or unsubstituted benzene ring is fused with R ⁴ and / or R ⁵ and R ⁶ . A photochromic compound represented by). 2. A compound of the general formula The photochromic compound according to claim 1, which is represented by the formula: