JP2001254074A - Photochromic molecule material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photochromic molecular material wherein the fluorescence intensity is greatly changed by light control. SOLUTION: The photochromic molecular material is represented by formula [I] (wherein ring A is a hydrocarbon ring or a heterocyclic ring; and ring B and ring C are each a 5-membered aromatic heterocyclic group, provided that ring B and/or ring C has a fluorescent substituent comprising a (non)substituted anthracene residue, an imidazole residue, an indole residue, a terphenyl residue, a fluorene residue or a pyrene residue).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a photochromic molecular material. More specifically, the present invention relates to a P-type photochromic molecular material having a large change in fluorescence intensity.

[0002]

2. Description of the Related Art A photochromic material is a material containing molecules or molecular aggregates that reversibly generate two isomers having different colors by the action of light. This photochromic material has a T-type in which the state of light generation is thermally unstable and returns to the original state in darkness, and a T-type which does not return to the original state thermally but has a different wavelength. There is a P type which returns to an original state by irradiation. When applied to a photonics device, it is an essential requirement that the device be a P-type. One of the P-type photochromic molecules is diheteroarylethene. Diheteroarylethene performs a photochromic reaction excellent in thermal irreversibility and repeated durability (M. Irie, K. Uchida, Bull. Che.
m. Soc, Jpn. , 71 (1998) 985). Until now, light irradiation using diheteroarylethene has been attempted to reversibly change not only color but also various physical properties such as refractive index, dielectric constant, oxidation / reduction potential, and to be applied as an optical functional material. (T. Kawai, NF
ukuda et al. Jpn. J. Appl. P
hys. 38 (1999) L1194, S.M. L. Gil
at, S .; H. Kawai et al. Chem.
Eur J. 1 (1995) 275). However, no reversible or large change in the fluorescence intensity has been obtained.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a molecular material which controls the fluorescence intensity by utilizing a photochromic reaction. It is in.

[0004]

The present inventors have studied various substitution positions and substituents on diheteroarylethene in order to optically control the fluorescence intensity. As a result, the present inventors have found that anthracene residues, imidazole residues, and indole residues are present. The present inventors have found that it is effective to introduce a fluorescent functional group such as a group into a heteroaryl ring, and have reached the present invention.

That is, the gist of the present invention is to provide a photochromic molecular material comprising a diheteroarylethene compound having a heteroaryl ring having a fluorescent substituent, and more preferably, the heterocyclic ring is a pyrrole ring, a thiophene ring, a thiazole ring, or an oxazole. Any of a ring, a furan ring and a selenophene ring, wherein the fluorescent substituent has an anthracene residue which may have a substituent, an imidazole residue which may have a substituent, and which has a substituent. Any of an optionally substituted indole residue, an optionally substituted terephenyl residue, an optionally substituted fluorene residue, and an optionally substituted pyrene residue Wherein the diheteroarylethene-based compound is a photochromic molecule represented by the general formula [I]. Fee on.

[0006]

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[In the general formula [I], A represents the following substituent [i], [ii] or [iii] (in the substituents [i], [ii] and [iii], R ¹ represents an alkyl group, an alkoxyl Represents a group, a halogen atom, a trifluoromethyl group, a cyano group or an aryl group which may be substituted, and R ² and R ³ each independently represent a hydrogen atom, an alkyl group, an alkoxyl group, a halogen atom, a trifluoromethyl group Represents a cyano group or an optionally substituted aryl group, or R ² and R ³ are connected to each other to form an optionally substituted hydrocarbon ring or an optionally substituted hetero ring, Y is -O-, -S- or -NR.
^4- (R ⁴ represents a hydrogen atom, an optionally substituted alkyl group, an optionally substituted aryl group or an optionally substituted cycloalkyl group);

[0008]

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B represents the following substituent [iv], [v] or [v
i] (in the substituents [iv], [v] and [vi], R
⁵ represents an alkyl group, an alkoxyl group, a halogen atom or a trifluoromethyl group, and R ⁶ and R ⁷ are each independently a hydrogen atom, an alkyl group, an alkoxyl group, a halogen atom, a trifluoromethyl group, a cyano group or a substituted May represent an optionally substituted aryl group, or R ⁶ and R ⁷ may be linked to each other to form an optionally substituted hydrocarbon ring or an optionally substituted heterocyclic ring.
Z is -O -, - S- or -NR ⁴ - (R ⁴ represents a hydrogen atom, an alkyl group which may be substituted, an optionally substituted aryl group or an optionally substituted cycloalkyl group ))),

[0010]

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In addition, at least one of R ^{1 to} R ⁷ has a fluorescent substituent. The term "heteroarylethene" means a structure represented by the following general formula [II].

[0012]

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[In the formula, ring A means, for example, a heterocyclic ring or a hydrocarbon ring as shown below;

[0014]

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Ring B and ring C mean a heteroaryl ring such as a pyrrole ring, a thiophene ring and a thiazole ring, that is, a 5-membered aromatic heterocyclic ring. The fluorescent substituent means a residue of a compound having a fluorescence quantum yield of 10% or more, preferably 20% or more. Specifically, for example, an anthracene residue optionally having a substituent, an imidazole residue optionally having a substituent, an indole residue optionally having a substituent, A terephenyl residue which may be substituted, a fluorene residue which may have a substituent, and a pyrene residue which may have a substituent.
Here, the optionally substituted anthracene residue is a monovalent or multivalent group obtained by removing a hydrogen atom from one or more carbon atoms in an optionally substituted anthracene. That is, a substituted or unsubstituted indolyl group in indole, such as a substituted or unsubstituted anthryl group, an anthrylene group, and a substituted or unsubstituted imidazolyl group in imidazole. ]

These fluorescent substituents are ring B and / or ring C
Or a group that is π-electron conjugated, such as

[0017]

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And the like.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
In the present invention, it has been found that diheteroarylethene having a heteroaryl ring group having a fluorescent substituent changes the fluorescence intensity with a photochromic reaction induced by light irradiation. Among these, preferred are, for example, compounds represented by the following general formulas (1), (2) and (3), wherein the heteroaryl ring has a pyrrole ring, a thiophene ring, a thiazole ring, or an oxazole ring. , A furan ring or a selenophene ring. Examples of the fluorescent substituent include an anthracene residue optionally having a substituent, an imidazole residue optionally having a substituent, an indole residue optionally having a substituent, and a Any of a terphenyl residue which may be substituted, a fluorene residue which may have a substituent, and a pyrene residue which may have a substituent. To h are candidates.

[0020]

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The introduction position may be any position.
c, f or g via a phenylene group, or a
hetero 5 in b and cd, ef and cd or ef and gh
In a structure in which a benzene ring is fused to a membered ring, it is effective to introduce a fluorescent substituent at the 4- to 7-positions of the fused ring. Specific examples of such compounds include the following compounds.

[0022]

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The fluorescence intensity of any of the compounds changes with light irradiation. In this example, the ethene moiety is only hexafluoropentene, but ethene composed of various hydrocarbon rings and heterocycles is also conceivable. For example, the following structure can be considered.

[0024]

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As is apparent from the above description, the present invention is directed to introducing a fluorescent functional group into a conventionally known photochromic compound comprising a diheteroarylethene compound having a heteroaryl ring (aromatic heterocyclic ring). ,
This is a photochromic molecular material whose fluorescence intensity is changed by light control, and includes an extremely wide range of compounds. The photochromic molecular material of the present invention can be produced according to a conventional method. Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples unless it exceeds the gist. Example 1

[0026]

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Under an argon atmosphere, 3-iodo-
90 mg of 2,5-dimethylthiophene (0.38 mm
ol) in 8 ml of anhydrous THF and 1.6 ml at -70 ° C.
0.25 ml of n-butyllithium in N hexane solution
(0.42 mmol) was added dropwise. After 30 minutes, anhydrous TH
77 mg of compound 1 dissolved in 5 ml of F (0.13 mm
ol), and the mixture was stirred for 1 hour, and methanol was added thereto, and the temperature was returned to room temperature. After extraction with chloroform, the extract was dried over anhydrous magnesium sulfate, separated by filtration, and chloroform was distilled off. This was developed and separated with a chloroform solvent using a silica gel column, and 52 mg of dithienylethene 2 was obtained.
(58% yield).

Compound 2: ¹ H NMR (CDCl ₃ ,
TMS, 200 Mhz) = 7.96-7.26 (m, 15H) 6.63 (s, 1H) 2.39 (s, 3H) 2.27 (s, 3H) 2.04 (s, 6H) MS m / z 690 (M ⁺ )

Example 2 Dithienylethane 2a (ring-opened product) synthesized in Example 1 was dissolved in hexane, and the fluorescence quantum yield was measured at an excitation wavelength of 366 nm. The result was 12%. The fluorescence quantum yield of diphenylimidazole, which is a compound corresponding to the imidazolyl group which is a fluorescent substituent in this compound, is 0.4.

The compound was irradiated with light having a wavelength of 313 nm to form a closed ring 2b, and the fluorescence quantum yield was measured at an excitation wavelength of 366 nm. The quantum yield was 1% or less. In the measurement of the fluorescence quantum yield and the ring closing reaction of the compound, a high-pressure mercury lamp (450 W, manufactured by Ushio Inc.) was used as a light source, and only a specific wavelength was extracted using a bandpass filter and used.

[0031]

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Example 3 Dithienylethene 3a having an anthracene residue was synthesized by the following method.

[0033]

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Compound 3a: 2.05 (6H, s, C
_{H 3) 2.07 (6H, s} , CH 3) 2.29 (6H, s, CH 3) 2.40 (6H, s, CH 3) 6.65 (2H, s, ArH) 7.47 ( 4H, d, ArH) 7.67 (4H, dd, ArH) 7.80 (4H, d, ArH) 8.70 (4H, dd, ArH)

Example 4 Dithienylethane 3a (ring-opened product) synthesized in Example 3 was dissolved in tetrahydrofuran (THF) and the fluorescence quantum yield was measured at an excitation wavelength of 410 nm.
78%. In addition, the fluorescence quantum yield of anthracene which is a compound corresponding to the fluorescent substituent (9,10-anthrylene group) in this compound is 30%.

The compound was irradiated with light having a wavelength of 313 nm to form a closed ring 2b, and the fluorescence quantum yield was measured at an excitation wavelength of 410 nm. The quantum yield was 3% or less. For the measurement of the fluorescence quantum yield and the ring closure reaction of the compound, a high-pressure mercury lamp (450 W, manufactured by Ushio Inc.) was used as a light source and only a specific wavelength was taken out using a band-pass filter, as in Example 2. did.

[0037]

According to the photochromic molecular material obtained by the present invention, the fluorescence intensity is greatly changed by light control, and the repetition durability is excellent. Therefore, a novel photonics device in information recording, display and technical fields can be used. It is a major contribution to this industrial field.

Claims (4)

[Claims] 1. A photochromic molecular material comprising a diheteroarylethene compound having a heteroaryl ring having a fluorescent substituent. 2. The photochromic molecular material according to claim 1, wherein the heteroaryl ring is any one of a pyrrole ring, a thiophene ring, a thiazole ring, an oxazole ring, a furan ring, and a selenophene ring. 3. An anthracene residue optionally having a substituent, an imidazole residue optionally having a substituent, an indole residue optionally having a substituent, The photochromic molecular material according to claim 1, which is a terphenyl residue which may have a group, a fluorene residue which may have a substituent, or a pyrene residue which may have a substituent. 4. The photochromic molecular material according to claim 1, wherein the diheteroarylethene compound is represented by the following general formula [I]. Embedded image [In the general formula [I], A represents the following substituent [i], [ii] or [iii] (in the substituents [i], [ii] and [iii], R ¹ represents an alkyl group, an alkoxyl group, a halogen Represents an atom, a trifluoromethyl group, a cyano group or an optionally substituted aryl group, and R ² and R ³ each independently represent a hydrogen atom, an alkyl group, an alkoxyl group, a halogen atom, a trifluoromethyl group, a cyano group Alternatively, it may represent an optionally substituted aryl group, or R ² and R ³ may be linked to each other to form an optionally substituted hydrocarbon ring or an optionally substituted heterocyclic ring. Y is -O -, - S- or -NR ⁴ - (R ⁴ represents a hydrogen atom, an alkyl group which may be substituted, an optionally substituted aryl group or an optionally substituted cycloalkyl group ) And, ## STR2 ## B represents the following substituent [iv], [v] or [vi] (in the substituents [iv], [v] and [vi], R ⁵ represents an alkyl group, an alkoxyl group, a halogen atom or a trifluoromethyl group) , R ⁶ and R ⁷ are each independently a hydrogen atom, an alkyl group, an alkoxyl group, a halogen atom,
Represents a trifluoromethyl group, a cyano group or an optionally substituted aryl group, or represents an optionally substituted hydrocarbon ring or an optionally substituted heterocyclic ring in which R ⁶ and R ⁷ are connected to each other; It may be formed. Z is -O-,
—S— or —NR ⁴ — (R ⁴ represents a hydrogen atom, an optionally substituted alkyl group, an optionally substituted aryl group or an optionally substituted cycloalkyl group) , In addition, at least one of R ^{1 to} R ⁷ has a fluorescent substituent described in claim 3. ]