JPH05222035A - Diarylethene compound - Google Patents

Abstract

PURPOSE:To provide a new diarylethene derivative which has excellent properties as a photochromic material such as high stability of the recorded matter to heat and moisture, high durability to repeated use and sensitivity to the semiconductor laser. CONSTITUTION:A diarylethene compound of formula I [n is 2 to 5; A is formula II [R1 is alkyl; R2 to R5 are H, alkyl, dialkylamino (at least one is this group); B is formula III (Rb is alkyl, alkoxy,; R7 is alkyl, cyano), formula IV (R8 to R11 are H, alkyl)], for example, 1-(1,2-dimethyl-5-dimethylamino-3-indolyl)-2-(5- cyano-2,4-dimethyl-3-thienyl)-3,3,4,4,5,5-hexafluorocyclopentene. The compound of formula I is prepared, for example, by reaction of a cycloperfluoroalkene derivative of formula V with a lithioaryl derivative ALi and BLi.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel diarylethene compound, and more particularly to a diarylethene compound having photochromic properties and suitable for optical recording materials and the like.

[0002]

2. Description of the Related Art In recent years, recording, storage materials, copying materials, light control materials, masking materials, printing photoconductors, photoconductors for lasers, photometers, or display materials are reversibly and appropriately changed in hue by light irradiation. Compounds having various photochromic properties have been proposed. For example, compounds such as benzospiropyrans, naphthoxazines, fulgides, diazo compounds and diarylethenes have been proposed as those photochromic compounds. In order to apply such a photochromic compound to a reversible optical recording material, the following properties are particularly required. That is, (1) recording stability, (2) repetitive durability, (3) high sensitivity, (4) semiconductor laser sensitivity, etc. However, the existing photochromic compound is generally thermally unstable in one of the colored state and the decolored state, and returns to a stable state within a few hours even at room temperature, so that the recording stability is improved. It has the drawback that it cannot be secured. Of the above compounds, the two states by irradiation with light are thermally stable, and perfluorocycloalkene-based diarylethenes are known to have high stability to moisture and oxygen, but their absorption in a colored state is low. Since it has a wavelength, there remains a problem that it is not sensitive to a semiconductor laser that can be easily used as an optical recording material, which is a major problem in using it as an optical recording material.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to ensure that recording is stable against heat, moisture, etc. Another object of the present invention is to provide a diarylethene derivative having excellent properties as a photochromic material such as excellent sensitivity to a semiconductor laser.

[0004]

The above-mentioned object is achieved by a diarylethene compound represented by the following general formula (1).

[Chemical 5] (1) (In the formula, n represents an integer of 2 to 5. A is

[Chemical 6] And B is

[Chemical 7] Or

[Chemical 8] Represents. R ₁ represents an alkyl group, and R _{2 to} R ₅ represent a hydrogen atom, an alkyl group or a dialkylaminoamino group. R ₆ represents an alkyl group or an alkoxy group, R ₇ represents an alkyl group or a cyano group, and R _{8 to} R ₁₁ represent a hydrogen atom or an alkyl group. At least one of R _{2 to} R ₅ represents a dialkylamino group. )

Next, the present invention will be described in detail. The diarylethene compound of the present invention is represented by the above general formula (1), n is an integer of 2 to 5, and has a cyclic structure of a 4 to 7 membered ring in cooperation with a double bond. Above all, n is 3 or 4
The 5- or 6-membered ring of 1 shows particularly preferable photochromic properties. A is

[Chemical 9] Represents an indolyl group represented by

[Chemical 10] Or

[Chemical 11] Represents a thienyl group or a benzothienyl group. R ₁ represents an alkyl group, preferably a lower alkyl group such as methyl, ethyl or propyl group. R _{2 to} R ₅ represent a hydrogen atom, an alkyl group or a dialkylamino group, and R ₆
Represents an alkyl group or an alkoxy group. R ₇ represents an alkyl group or a cyano group, and R _{8 to} R ₁₁ represent a hydrogen atom or an alkyl group, and at least one of R _{2 to} R ₅ is a dialkylamino group. It is necessary to extend the wavelength to the emission wavelength range. A longer absorption wavelength can be achieved by the effect of the electron-donating dialkylamino group.

The diarylethene derivative of the present invention can be produced by various methods, for example, the following method. That is, the following general formula (2)

[Chemical 12] The cycloperfluoroalkene derivative represented by (2) (n is 2
To an integer of 5) and lithioaryl derivatives ALi and BLi
(A and B are the same as above), the following general formula (3)

[Chemical 13] (3) (wherein, n, A, and B are the same as above), there is a method of reducing and coupling the carbonyl groups in the molecule using low-valent titanium. The former is simpler and preferable. An example of a suitable former manufacturing method is as follows. First, the following general formula (4) or (5)

[Chemical 14] … (4)

[Chemical 15] (5) (However, X and Y represent a bromine atom or an iodine atom.
R _{6 to} R ₁₁ are the same as above. ), A thienyl halide derivative or a benzothienyl halide derivative represented by the formula (1) is reacted with an alkyllithium or a lithium dialkylamide to obtain a thienyllithio derivative or a benzothienyllithio derivative in which halogen is replaced with lithium. As the solvent, an ether solvent such as tetrahydrofuran or diethyl ether is preferably used, and a lower alkane such as n-hexane or n-pentane may be mixed to prevent solvent coagulation at a low temperature. Alkyllithium as a lithiation agent,
Examples of the lithium dialkyl amide include n-butyl lithium, t-butyl lithium, methyl lithium, phenyl lithium, lithium diisopropyl amide, lithium dicyclohexyl amide, and the like, and a hexane solution of n-butyl lithium is preferably used. The amount of the lithiating agent is preferably 1.0 to 1.2 times the molar amount of the total amount of the thienyl halide derivative or the benzothienyl halide derivative.

The reaction temperature is −45 to −120 ° C., preferably −70 to −110 ° C. The reaction time is usually 20 minutes to 3 hours, preferably 30 minutes to 2 hours. Next, the generated thienyl lithiated derivative or benzothienyl lithiated derivative is represented by the following general formula (2)

[Chemical 16] (2) (wherein n represents an integer of 2 to 5) is added, and the amount of the perfluorocycloalkane compound used is 1. The amount of the thienyl halide derivative or benzothienyl halide derivative.
It is preferably used in an amount of 0 to 1.5 times, and can be added without dilution or after being diluted with a solvent. Usually, the reaction temperature is -60 to -110 ° C, and the reaction time is 30 minutes to
5 hours. After completion of the reaction, water or alcohol may be added immediately to complete the reaction, or the reaction may be completed after returning the liquid temperature to room temperature, but it is better to complete the reaction at a low temperature. Is good. Thus, the monothienylethene derivative represented by the general formula (6) or the monobenzothienylethene derivative represented by the general formula (7) is obtained.

[Chemical 17] … (6)

[Chemical 18] (7) (However, n and R _{6 to} R ₁₁ are the same as above.)

Next, the general formula (8)

[Chemical 19] (8) (wherein Z represents a bromine atom or an iodine atom, R _{1 to} R
₅ is the same as above. In the same manner as described above, the dialkylaminoindolyl halide derivative represented by the formula (4) is converted to a dialkylaminoindolyllithiated derivative, and the above-mentioned monothienylethene derivative or monobenzothienylethene derivative in tetrahydrofuran is added thereto. The amount of the thienylethene derivative or monobenzothienylethene derivative is preferably 1.0 to 1.2 times the molar amount of the dialkylaminoindolyl halide derivative. Usually, this reaction temperature is -60 to -110 ° C, and the reaction time is 30 minutes to 5 hours. After completion of the reaction, water or alcohol may be added immediately to complete the reaction, or the reaction may be completed after the liquid temperature is returned to room temperature, but it is better to complete the reaction at low temperature. Is good. As a production method, contrary to the method of reacting the monoarylethene derivative represented by the general formula (6) or (7) with the dialkylaminoindolyl halide derivative represented by the general formula (8) as described above, From the dialkylaminoindolyl halide derivative represented by the general formula (8), the following general formula (9)

[Chemical 20] (9) (wherein n, R _{1 to} R ₅ are the same as above), after synthesizing the mono (dialkylaminoindolyl) ethene derivative, the thienyl represented by the general formula (4) or (5) It may be reacted with a halide derivative or a benzothienyl halide derivative. The lithiation reaction, the synthesis of monoarylethene, and the synthesis of diarylethene can be performed under the same conditions as in the above-mentioned production method.

As another production method, the dialkylaminoindolyl halide derivative represented by the general formula (8), the thienyl halide derivative represented by the general formula (4) or the benzo represented by the general formula (5). It is also possible to react with the thienyl halide derivative at the same time. That is, an ordinary equimolar mixture of the thienyl halide derivative represented by the general formula (4) and the dialkylaminoindolyl halide derivative represented by the general formula (8) is used, and the amount of the lithiating agent is changed to the thienyl halide derivative and the dialkylamino. 1. Total amount of indolyl halide derivative
The lithiation reaction is carried out under the same conditions as in the above-mentioned production method except that the molar amount is 0 to 1.2 times. Then, it can be obtained by adding the perfluorocycloalkane compound represented by the general formula (6) under the same conditions as in the above-mentioned production method.

The former two sequential reactions have the advantage of selectively obtaining the target diarylethene compound into which two types of aryl groups have been introduced, while the final simultaneous reaction has the advantage of a one-pot two-step reaction. It is a feature. As an example of the diarylethene compound of the present invention, 1- (1,2-dimethyl-5-dimethylamino-3-indolyl) -2- (5-
Cyano-2,4-dimethyl-3-thienyl) -3,3,
Explaining an example of 4,4,5,5-hexafluorocyclopentene, it changes to a ring-closed body by ultraviolet light and is colored green as shown in the following formula (10).

[Chemical 21]

[Chemical formula 22] (10) Further, when the closed ring is irradiated with visible light, it returns to the original open ring and disappears. The diarylethene derivative of the present invention is
Both the colored state and the decolored state have high thermal stability, are stable to moisture, do not change for a long time, and are well retained. Further, it has excellent durability against repeated coloring and decoloring, and can be advantageously used for a reversible optical information recording material. Since the absorption maximum wavelength in the colored state exceeds 650 nm and the absorption edge becomes 850 nm or more, a semiconductor laser having an oscillation wavelength of 670 nm or 780 nm can be used, and can be suitably used as an optical recording material.

The optical recording material of the present invention utilizing the recording layer containing the diarylethene photochromic compound of the present invention can be easily obtained by a known method. For example, a method of depositing the diarylethene compound of the present invention on a suitable substrate by a known vapor deposition method, a polyester resin, a polystyrene resin, a polyvinyl chloride resin, a polyvinyl acetate resin, a diarylethene compound of the present invention,
With resin binders such as polyvinyl butyral resin, polymethylmethacrylic acid resin, polycarbonate resin, phenol resin, epoxy resin, benzene, toluene,
Hexane, cyclohexane, methyl ethyl ketone, acetone, methanol, ethanol, tetrahydrofuran,
Dispersed or dissolved in a solvent such as dioxane, chloroform, carbon tetrachloride and the like, a method of coating on a suitable substrate, a method of dissolving the diarylethene compound of the present invention in the solvent as described above, enclosed in a glass cell or the like, An optical recording material can be obtained by forming a recording layer using the above method.

[0012]

INDUSTRIAL APPLICABILITY As described above, the diarylethene compound of the present invention is excellent in thermal stability and moisture resistance, has good photochromic property of repeated durability of coloring and erasing, and records or erases with a semiconductor laser. Therefore, a reversible optical recording material having excellent performance can be obtained by using this. The present invention will be specifically described below with reference to examples.

Example 1 (1) Synthesis of 1- (5-cyano-2,4-dimethyl-3-thienyl) -2,3,3,4,4,5,5-heptafluorocyclopentene 2 l 2-cyano-3,5-dimethyl-4-iodothiophene 42.1 g (0.16 mol) in a 3-necked flask
Was charged and the atmosphere was replaced with nitrogen. 1.6 l of previously dried tetrahydrofuran and 160 ml of n-hexane were added and dissolved therein. After cooling the reaction system to -92 ° C, 1.6
100 ml of a specified n-butyllithium / hexane solution (0.
16 mol) was added dropwise in 30 minutes. 1 at the same temperature after dropping
After stirring for 3 hours, 36.0 g of perfluorocyclopentene
What melt | dissolved (0.17 mol) in 340 ml of tetrahydrofuran was dripped in 30 minutes. After stirring at the same temperature for 1 hour, the temperature was raised to -50 ° C in 1 hour, 20 ml of methanol was added to terminate the reaction, and the mixture was poured into saturated saline. Next, after extraction with ethyl acetate and drying over magnesium sulfate, the solvent was distilled off and the desired product was isolated by column chromatography (silica gel, eluent n-hexane / ethyl acetate = 20/1). 32.7 g of a pale yellow solid of 5-cyano-2,4-dimethyl-3-thienyl) -2,3,3,4,4,5,5-heptafluorocyclopentene was obtained. (Yield 62.0%) <Analytical value> MS (m / e) 329 (M ⁺ ) ¹ H-NMR (CDCl ₃ ) δ (ppm) 2.41
(S, 3H) 2.49 (S, 3H) IR 2200cm ^-1 (C≡N)

(2) 1- (1,2-dimethyl-5-dimethylamino-3-indolyl) -2- (5-cyano-
2,4-dimethyl-3-thienyl) -3,3,4,4
Synthesis of 5,5-hexafluorocyclopentene 10.2 g (38 mm) of 3-bromo-1,2-dimethyl-5-dimethylaminoindole in a 1 l two-necked flask.
ol) was added and the atmosphere was replaced with nitrogen. Pre-dried tetrahydrofuran 3.00 ml, n-hexane 30 ml
Was added and dissolved. 1.6 after cooling to -92 ° C
24 ml (38 mmol) of a specified n-BuLi hexane solution was added to 1
It was added dropwise in 5 minutes. After completion of dropping, the mixture was stirred at the same temperature for 30 minutes and then synthesized in (1) 1- (5-cyano-2,4-dimethyl-3-thienyl) -2,3,3,4,4,5,5-
12.5 g (38 mmol) of heptafluorocyclopentene
A solution dissolved in 50 ml tetrahydrofuran was added. Stir for 30 minutes at the same temperature, gradually raise the temperature and in 1 hour-
After the temperature was raised to 50 ° C., 10 ml of methanol was added to terminate the reaction, and the mixture was poured into saturated saline. Next, the mixture was extracted with ethyl acetate, dried over magnesium sulfate, the solvent was distilled off, and the desired product was isolated by column chromatography (silica gel eluent n-hexane / ethyl acetate = 5/1). Further reconstitution with methanol gives 1- (1,2-dimethyl-
5-dimethylamino-3-indolyl) -2- (5-cyano-2,4-dimethyl-3-thienyl) -3,3
5.2 g of yellow crystals of 4,4,5,5-hexafluorocyclopentene were obtained. (Yield 37.2%)

[Chemical formula 23] ¹ H-NMR (CDCl ₃ ) 7.26 to 6.65
(M, 3H) 3.58 (S, 3H) 2.93 (S,
6H) 2.33 (S, 3H) 2.13 (S, 3H)
1.98 (S, 3H)

(3) Photochromic property A solution obtained by dissolving the compound synthesized in the above (2) in n-hexane to a concentration of 10 ^-4 mol 1 l is 1 × 1 × 4 cm.
100 W mercury lamp (manufactured by OSRAM Co., Ltd.), which was filled in a quartz glass cell of No. 3, and equipped with a 365 nm interference filter (manufactured by Nippon Vacuum Optical Co., Ltd.), was colored green when irradiated with ultraviolet light for 1 minute. The absorption spectrum is shown by the solid line in FIG. Has a maximum absorption at 705 nm and an absorption edge of 870 nm
Changed to the one shown by the dotted line. Next, when the solution colored green was irradiated with light of 780 nm for 1 minute by a 100 W mercury lamp equipped with an interference filter (manufactured by Nippon Vacuum Optical Co., Ltd.), the color immediately disappeared and the original light yellow state was changed. This change could be reversibly repeated.

(Example 2) (1) 1- (2-methyl-3-benzothienyl) -2,
Production of 3,3,4,4,5,5-heptafluorocyclopentene In a 500 ml three-necked flask, 11.4 g (50 mmol) of 3-bromo-2-methylbenzothiophene was dissolved in 250 ml of diethyl ether, and a nitrogen stream was introduced. Under -60 ℃,
50 mmol of 1.6N n-butyllithium hexane solution
Was added dropwise over 30 minutes and stirred for 1 hour. Next, 50 mol of a diethyl ether solution containing 10.6 g (50 mmol) of perfluorocyclopentene was added dropwise over 30 minutes. Three
The reaction was allowed to proceed for a time, methanol was added dropwise to terminate the reaction, the mixture was washed with water, and extracted with diethyl ether three times. The diethyl ether layers were collected and dried, and then diethyl ether was distilled off. The reaction product was separated and purified by silica gel column chromatography, and 1- (2-methyl-3-benzothienyl) -2,3,3,4,4,5,5-heptafluorocyclopentene having the following structure was obtained. Obtained as 14.5 g (yield 85%) as yellowish white crystals.

[Chemical formula 24] Analytical value: (I) ¹ H-NMR (CDCl ₃ ) δ (ppm) 2.51 (S, 3H) 7.20 to 8.
00 (m, 4H) (II) MS (m / e) 340 (M ⁺ )

(2) 1- (1,2-dimethyl-5-dimethylamino-3-indolyl) -2- (2-methyl-3)
-Benzothienyl) -3,3,4,4,5,5-hexafluorocyclopentene Synthesis 3-bromo-1,2-dimethyl-5-dimethylaminoindole 7.85 g in the same manner as in Example 1 (1). (29.4 mmol) and 1- (2-
Methyl-3-benzothienyl) -2,3,3,4,4
5,5-heptafluorocyclopentene 10.0 g (2
9.4 mmol) of 1- (1,2-dimethyl-5-dimethylamino-3-indolyl) -2- (2 having the following structure
-Methyl-3-benzothienyl) -3,3,4,4
14.8 g of 5,5-hexafluorocyclopentene
(Yield 98%) was obtained.

[Chemical 25] <Analytical value> ¹ H-NMR (CDCl ₃ ) 7.72 to 6.78
(M, 7H) 3.45 (S, 3H) 2.81 (S,
6H) 2.20 (S, 3H) 1.93 (S, 3H)

(3) Photochromic property When irradiated with ultraviolet light in the same manner as in Example 1- (3), it has an absorption maximum at 630 nm, and the absorption edge has an absorption edge of 8
The absorption spectrum changed to 20 nm. This colored body returned to its original pale yellow state upon irradiation with 780 nm light, and a reversible change was observed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing optical changes in absorption spectrum of a compound synthesized in Example 1 in an n-hexane solution. FIG. 2 is a view showing the optical change of the absorption spectrum of the compound synthesized in Example 2 in n-hexane.

Claims (1)

[Claims] 1. A diarylethene compound represented by the following general formula (1): [Chemical 1] (1) (In the formula, n represents an integer of 2 to 5. A is And B is Or Represents. R ₁ represents an alkyl group, and R _{2 to} R ₅ represent a hydrogen atom, an alkyl group or a dialkylaminoamino group. R ₆ represents an alkyl group or an alkoxy group, R ₇ represents an alkyl group or a cyano group, and R _{8 to} R ₁₁ represent a hydrogen atom or an alkyl group. At least one of R _{2 to} R ₅ represents a dialkylamino group. )