JP2003321467A - Photochromic material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a diarylethene-based compound having large conversion in photochromic reaction and having high diastereofacial selectivity. <P>SOLUTION: This diarylethene-based photochromic compound is expressed by general formula (I) [X and Y are each an aromatic ring; R<SP>1</SP>is a substituent having an asymmetric carbon atom to which A, B, and C (A, B, and C are each H, a halogen, an alkyl, an alkoxy, an alkoxycarbonyl, an alkoxycarbonyloxy or an aryl which may be substituted and are different from each other, or may be bonded to each other to form a ring) are each bonded; R<SP>2</SP>may be similar to or different from R<SP>1</SP>, provided that R<SP>2</SP>is an alkyl, an alkoxy, an acryl or the like when R<SP>2</SP>is different from R<SP>1</SP>; R<SP>3</SP>and R<SP>4</SP>are each H, a halogen, an alkyl, an alkoxy, an acyl or the like which may be similar to or different from each other, or may be bonded to each other to form a ring]. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a chiral forochromic compound, a photochromic material using the same, and an optical element.

[0002]

Photochromic materials are materials containing molecules that reversibly produce structural isomers with different absorption spectra (ie, "color") by the action of light. Photochromic materials reversibly generate compounds with different structures upon irradiation with light. Therefore, reversible changes in various physical properties such as absorption spectrum, melting point, refractive index, viscosity, and polarity can be induced by irradiation with light. It is possible. Utilizing such changes in various characteristics associated with the photochromic reaction, application development to optical recording media, display devices, optical filters, light modulators, light control lenses, light control windows, etc. has been studied. High cyclic durability is an important factor in the application and development of photochromic materials, and diarylethene-based molecules have been obtained with sufficient cyclic durability (M. Irie,
et al., J. Chem. Soc., Chem. Commun., 206, (199
2).). When a photochromic material is used for an optical recording medium, it is important to have a non-destructive read-out function for recording, in addition to repeated durability. That is, in the case of reading recorded / unrecorded information as a difference in absorption spectra of two isomers produced by the photochromic reaction,
It is necessary to irradiate light having a wavelength corresponding to the absorption band, and there is essentially a problem that recorded information is changed (record is destroyed) by the reading light. There is a proposal to read the record with a weak light (T. Tsujioka, e.
al., Jpn. J. Appl. Phys., 34, 6439, (1995).), since there is no threshold in the photoreaction, no matter how weak the light is read out, it will be read many times. The record will be destroyed afterwards as well.

For this problem, a method of giving a threshold to the photochromic reaction has been studied. A system in which a hydrogen-bonding functional group is introduced into the diarylethene molecule to impart temperature dependence to the photochromic reaction (M. Irie, et al., J. Am.
Chem. Soc., 116, 9894, (1994).), A system combining a redox reaction and a photochromic reaction by introducing a redox active site into a diarylethene molecule (J.
M. Lehn, et al., Chem. Eur. J., 1, 285, (199
5).), A system combining the acid-base equilibrium reaction of fulgide and the photochromic reaction (Y. Yokoyama, et al., J. Che.
m. Soc., Chem. Commun., 1722, (1991).) has been proposed. However, the above-mentioned method has a drawback that the system is complicated because a light source (light stimulus) required for the photochromic reaction and other additional stimuli (heat, potential difference, and another chemical species) are required. However, it is not practical in terms of recording speed.

[0004]

In order to solve such problems, studies have been made on a method of detecting reversible changes in physical properties associated with a photochromic reaction with light having a wavelength that does not induce the photochromic reaction. As a method of nondestructively reading recorded information, a method of reading a change in optical rotation accompanied by photochromism by using light in a wavelength range where the photochromic compound is not sensitive has been proposed (JP-A-7-302425). When applying this method,
It is necessary that the photochromic molecule has asymmetry and is not racemic. Optical resolution of photochromic molecules with asymmetric elements in the molecular skeleton has been investigated, but this method is anxious about thermal racemization (Y. Yokoyama,
et al., J. Chem. Soc., Chem. Commun., 758, (199
Five).). Moreover, it is possible to obtain an optically active photochromic molecule by modifying the molecule with an asymmetric substituent that is less likely to racemize, but simply introducing an asymmetric modifying group into the photochromic molecule causes reversible photochromic reaction. The change in optical rotation is small, and the modulation of the recording signal cannot be increased.

Therefore, in order to apply the photochromic material to a recording medium, it is necessary to develop a molecule in which the photochromic molecule has asymmetry and the asymmetric site itself directly changes with the photochromic reaction. That is, it is necessary to design a molecule in which an asymmetric bias is induced at the site where the structure changes with the photochromic reaction due to the effect of the asymmetric modifying group (the photochromic reaction is diastereoselective). It is important that the chiral source creates molecules that are difficult to racemize by repeated light irradiation and heat. As such a compound, Irie et al. Reported a diarylethene compound into which an asymmetric modifying group showing a diastereoselective photocyclization reaction was introduced. However, those compounds reported so far can exhibit high diastereoselectivity only in a single crystal and under the condition that the conversion rate of the photochromic reaction is 10% or less (M. Irie, et al. al., J. Am. Chem. Soc., 122, 9
631 (2000).), Or high diastereoselectivity is exhibited only at a low temperature of −40 ° C. or in a polar solvent, and in addition, under such conditions, the conversion rate of the photochromic reaction is 10%.
There was a problem that it was extremely reduced to about%.
For example, in a hexane solution, the conversion rate of the photochromic reaction by irradiation with 450 nm light at room temperature is 42.5%, and the diastereomer excess rate at this time is 0%. The mer excess increases to 72.2%, but the conversion of the photochromic reaction at this time is only about 10% (Japanese Patent Laid-Open No. 9-77767 and M. Irie, et a.
L., J. Am. Chem. Soc., 119, 6066, (1997).).

A molecule having two photochromic moieties has been reported for the purpose of increasing the change in optical rotation accompanied by photochromism (Japanese Patent Laid-Open No. 10-60424).
In order to induce a large change in optical rotation, it is necessary to react both photochromic sites, which is not preferable from the viewpoint of recording energy efficiency.

Under these circumstances, the present invention has developed an asymmetric photochromic molecule in which the asymmetric site itself directly changes with the photochromic reaction, and has an effective conversion rate and asymmetric induction efficiency of the photochromic reaction. It is an object of the present invention to create molecules that can be compatible with each other regardless of the properties (polarity) of a medium, and to provide an optical element using the molecule.

[0008]

In the present invention, the photochromic reaction characteristics and diastereoselectivity of the diarylethene-based molecule are influenced by the asymmetric carbon atoms adjacent to the photocyclizing carbon atoms of the diarylethene-based molecule. It is possible to control the configuration of the two carbon atoms in the colored product generated by the photocyclization reaction with high selectivity, and thus to apply it to recording media, etc. using changes in optical rotation and refractive index. The present invention has been completed and the present invention has been completed.

That is, the present invention is a photochromic compound represented by the following general formula (I).

[Chemical 2]

In the formula, X and Y represent an aromatic ring. R ¹ represents a substituent having an asymmetric carbon bonded to A, B and C,
A, B, and C represent a hydrogen atom, a halogen atom, and an alkyl group which may be substituted, an alkoxy group, an alkoxycarbonyl group, an alkoxycarbonyloxy group, and three different groups selected from aryl groups, or Alternatively, A, B and C may combine with each other to form a ring. The alkyl group, the alkoxy group, the alkoxycarbonyl group, the alkoxycarbonyloxy group, the substituent of the aryl group, a hydroxyl group, a halogen, a nitro group,
Examples thereof include a cyano group, an alkyl group, an alkoxy group, an alkylthio group, an aryl group, an arylthio group, an amino group, an alkylamino group, a sulfone group, a carboxyl group and an acyl group. R ² may be the same as or different from R ¹ ,
When they are different, an alkyl group which may be substituted, an alkoxy group, an acyl group, an amino group, an alkoxycarbonyl group, an aryloxy group, an aryl group, a carbamoyl group, a nitro group, a cyano group, a halogen atom and the like can be mentioned. Substituents for these groups include hydroxyl, halogen,
Nitro group, cyano group, alkyl group, alkoxy group, alkylthio group, aryl group, arylthio group, amino group,
Examples thereof include an alkylamino group, a sulfone group, a carboxyl group and an acyl group. R ³ and R ⁴ may be the same or different and each is a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an acyl group, an amino group, an alkoxycarbonyl group, an aryloxy group, an aryl group, a carbamoyl group, a nitro group, a cyano group. A general substituent such as a group may be mentioned, but in this case, the EZ isomerization reaction of the double bond simultaneously occurs in addition to the photochromic reaction, and the efficiency of the photochromic reaction decreases, so R ³ and R ⁴ are mutually different. It is preferred that they combine to form a ring. The number of carbon atoms in the alkyl group, alkoxy group and acyl group in A, B, C and R ² is preferably 1 to 20, and the aryl group is a phenyl group, a pyridyl group, a pyrimidyl group, a triazyl group or a pyran ring, A group derived from a 5-membered aromatic ring such as a pyrrole ring is preferable. In addition, R ³ , R ⁴
The number of carbon atoms in the alkyl group, alkoxy group and acyl group in is preferably 1 to 4, and the aryl group is preferably a phenyl group.

When R ³ and R ⁴ form a ring,

[Chemical 3] A cyclic structure such as is preferably used, and R ⁵ represents a hydrogen atom, a halogen atom, an optionally substituted alkyl group or an aryl group. Especially the conversion rate of photochromic reaction,
A compound having hexafluorocyclopentene is most preferable from the viewpoints of repeated durability and thermal stability.

In the general formula (I), X and Y may be the same or different and are preferably 5-membered or 6-membered heteroaromatic rings composed of carbon, sulfur, nitrogen, oxygen and selenium. Is an alkyl group, an alkoxy group, an alkoxycarbonyl group, a carboxyl group, an aryloxy group, an aryl group, a halogen atom, an amino group, a nitro group,
It may have a substituent such as a cyano group. A hetero 5-membered ring such as a furan ring, a pyrrole ring, a pyrazole ring, or an imidazole ring is preferably used from the viewpoint of the thermal stability of the ring-closed compound. Those having a ring structure are preferable.

[0013]

[Chemical 4]

R ⁶ and R ⁷ are not only hydrogen atoms, but also halogen atoms, alkyl groups, alkoxy groups, aryloxy groups,
It may be an amino group, a nitro group or the like, and may combine with each other to form a ring. Further, in order to prevent side reactions such as oxidation reaction, the following benzo-condensed structure is more preferable from the viewpoint of repeated durability.

[0015]

[Chemical 5]

Here, R ⁸ to R ¹¹ may be a halogen atom, an alkyl group, an alkoxy group, an aryloxy group, an amino group, a nitro group, etc., in addition to a hydrogen atom, and they are further bonded to each other to form a ring. May be.

Further, a compound having a specific helicene-like structure in the molecular structure as represented by the following general formula (II) remarkably changes the optical rotation and dichroism for light in the long wavelength region. It is preferable because it is possible.

[Chemical 6]

In the general formula (II), R ¹ is

[Chemical 7] The stands, R ² is an optionally substituted alkyl group, an alkoxy group, an acyl group, an amino group, an alkoxycarbonyl group, an aryloxy group, an aryl group, a carbamoyl group, a nitro group, a cyano group, a group such as a halogen atom Represents R ³ and R ⁴ may be the same or different and each is a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an acyl group, an amino group, an alkoxycarbonyl group, an aryloxy group, an aryl group, a carbamoyl group, a nitro group, a cyano group. Represents a substituent such as a group, and the EZ isomerization reaction of the double bond occurs at the same time in addition to the photochromic reaction, and the efficiency of the photochromic reaction decreases, so R ³ and R ⁴
Are preferably bonded to each other to form a ring. R ¹² represents an optionally substituted alkyl group.

The diarylethene compound of the present invention can be synthesized by the following method. R ³ and R ⁴ have a ring structure, and R ³ and R ⁴ are

[Chemical 8] in the case of,

[Chemical 9] Or a reaction by coupling an aryl lithiated with a perfluorocycloalkene, or

[Chemical 10] It can be synthesized by the route.

R ³ and R ⁴ are

[Chemical 11] in the case of,

[Chemical 12] As described above, the compound can be synthesized by cyanating the chloromethyl group, then coupling, hydrolyzing and dehydrating and cyclizing.

R ³ and R ⁴ are

[Chemical 13] In the case of, it is derived from the maleic anhydride to an imide, or

[Chemical 14] It can be synthesized by the method of.

The diarylethene compound of the present invention obtained by such a method exhibits a ring-closing reaction and a ring-opening reaction with light irradiation. The ring-closure product produced by the photocyclization reaction has two new asymmetric carbons, and has a total of three asymmetric carbons in combination with the asymmetry of the substituent R ¹ (* in the figure below indicates an asymmetric carbon). At this time, as shown below, in the ring-closed form, 2 of (IA) and (IB) which are in a diastereomeric relationship
It is possible that seeds will form. When the substituent R ¹ does not have an asymmetric carbon, (IA) and (IB) are always produced in equal proportions, but the diarylethene compound of the present invention is a carbon that cyclizes to an asymmetric carbon. It is possible to control the abundance ratio of diastereomers produced by the photocyclization reaction with high selectivity by introducing an asymmetric carbon at the adjacent position of.

[0023]

[Chemical 15]

This selectivity is R¹Or R¹And R²Introduced in
Due to the steric effect of the asymmetric modifying group
It is presumed that the information is biased. That is, below
As shown in the figure, the ring-opened product of the diarylethene compound is
Due to steric hindrance, the conjugated system of hexatriene part is in the same plane
Can't be on top, screw right-handed or left-handed
Take the conformation that was set. Substituent R¹Is an asymmetric carbon
If you do not have a right-handed and left-handed conformation
Of the present invention are present in equal proportions and are present in a 1: 1 ratio.
The diarylethene compound in¹Asymmetric carbon to
With the introduction of the right-handed and left-handed conformations
There is a difference in stability. For example, in the figure below, the left conformation
The substituent B and the aromatic ring Y (and bound to Y
Substituent R ²), A three-dimensional repulsion occurs, but
In the formation, the substituent C and the aromatic ring Y (and bonded to Y
Substituent R²) Between three-dimensional repulsion will occur. R¹
When is an asymmetric carbon, the substituents B and C have size, electronic state, etc.
Aromatic ring Y (and the substituent bonded to Y
R²) Inevitably differs, and these are the two types in the figure below.
Results in a bias in the abundance of conformations of
It Since the photocyclization reaction proceeds by reflecting the stereochemistry of the ring-opened body.
(Woodward-Hoffman rule), conf on the left side in the figure below
When the existence ratio of the formation is large, (I-
A) is selectively generated and the conformation on the right side in the figure below
If there is a large presence ratio, (IB) in the above figure is selected.
It will be generated selectively. Thus A, B, and
It is easy to obtain the absolute value of the photocyclization reaction product from the substituent introduced into C.
It is possible to predict the configuration. And that's all
Asymmetric carbons adjacent to the photocyclizing carbon atom
As a result, asymmetric induction is effectively expressed.

[0025]

[Chemical 16]

Optical elements such as information recording media, dimming media, and display media containing the diarylethene compound of the present invention can be easily produced according to known methods.
For example, alcohol, toluene, chloroform, benzene, ether and other solvents, if necessary polyester,
Dissolve with a resin such as polystyrene or polyvinyl chloride and form a film on a suitable substrate, or by a known vapor deposition method or co-evaporation method with other compounds, vapor deposition on a suitable substrate, etc. You can do it. It is also possible to use it as a crystal as it is, and it may be dissolved or dispersed in an appropriate solvent and enclosed in a glass cell or the like.

As the film forming method, a generally used film forming method such as a casting method, a dipping method, a spin coating method, a doctor blade method, a vacuum vapor deposition method, a sputtering method and an LB film method can be used.

In order to improve the durability of the photochromic material, a transition metal chelate compound such as bisphenyldithiol, acetylacetonate chelate or salicylaldehyde may be mixed as a singlet oxygen quencher, or other light stabilizers may be added. You may use it with a material.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, examples will be given to explain the present invention, but the present invention is not limited to these examples.

Example 1 (Diarylethene 1) was synthesized by the following synthetic route.

[Chemical 17]

Synthesis of compound (1-2) 4.13 g (30.7 mmol, 1.0 eq.) Of benzo [b] thiophene and a spinner were placed in a 300 ml three-necked flask, the system was replaced with nitrogen, and tetrahydrofuran 1
00 ml was added. After cooling to -25 ° C, n-butyllithium 1.60 mol · dm ^-3 hexane solution 23.0 m
1 (36.8 mol, 1.2 eq.) was added and stirred for 5 minutes. There, N, N, N ', N'-tetramethylethylenediamine 5.6 ml (37.4 mmol, 1.2e)
q. ) Was added and the mixture was further stirred for 100 minutes. There, 4.10 ml of acetaldehyde (74.0 mmol, 2.4
eq. ) Is added and the temperature is gradually raised from -25 ° C to 5
Stir for hours. Water was added to the reaction system to terminate the reaction, ethyl acetate was added to separate the layers, and the aqueous layer was extracted 4 times with ethyl acetate. The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and dried. After the desiccant was filtered off by suction filtration, the solvent was distilled off under reduced pressure. The residue was purified by flash column chromatography to give compound (1-2)
Was obtained as a white solid. Yield 4.61 g (25.8 mmo
l), 84% yield.

¹ H NMR (270 MHz, CDCl ₃ , TMS) δ / ppm;
1.66 (3H, d, J / Hz = 6.27), 2.09 (1H, d, J / Hz = 4.62),
5.21 (1H, quint, J / Hz = 5.94), 7.19 (1H, s), 7.27〜
7.36 (2H, m), 7.72 (1H, d, J / Hz = 8.25), 7.81 (1H,
d, J / Hz = 8.25) IR (nujol) ν / cm ^-1 ; 3272, 2922, 1462, 1455, 742,
724 Melting point: 61-63 ℃

Synthesis of Compound (1-3) Sodium hydride (60%) was added to a 100 ml two-necked flask.
in oil) 513.3 mg (12.83 mmol, 1.
5 eq. ) And a spinner were added, the system was replaced with nitrogen, 20 ml of tetrahydrofuran was added, and the mixture was cooled to 0 ° C. On the other hand, the compound (1
-2) white solid 1.49 g (8.36 mmol, 1.
0 eq. ) And spinner, and after replacing the system with nitrogen,
20 ml of tetrahydrofuran was added. This solution was added dropwise to the above 100 ml two-necked flask, and the mixture was stirred for 45 minutes while maintaining the temperature at 0 ° C., and then chloromethyl methyl ether (0.1 ml) was added.
90 ml (11.9 mmol, 1.4 eq.) Was added, and the mixture was stirred for 3 days while gradually returning to room temperature from 0 ° C.
Water and ethyl acetate were added to the reaction system for liquid separation, and the aqueous layer was extracted twice with ethyl acetate. This organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and then removed by suction filtration. After the solvent was distilled off under reduced pressure, the residue was purified by flash column chromatography to obtain compound (1-3) (colorless transparent liquid). Yield 1.67
g (7.50 mmol), yield 90%.

¹ H NMR (270 MHz, CDCl ₃ , TMS) δ / ppm;
1.63 (3H, d, J / Hz = 6.60), 3.42 (3H, s), 4.66 (2H, d
d, J / Hz = 19.79, 6.93), 5.10 (1H, q, J / Hz = 6.49), 7.20
(1H, s), 7.26 ~ 7.36 (2H, m), 7.70 ~ 7.73 (1H, d, J
/Hz=8.91),7.79 to 7.83 (1H, d, J / Hz = 8.58) IR (KRS-5, neat) ν / cm ^-1 ; 3058, 2977, 2930, 288
7, 1458, 1436, 1162,1097, 1029, 748

Synthesis of Compound (1-4) A 100 ml two-necked flask was charged with the compound (1
-3) 693.8 mg (3.12 mmol, 1.0e)
q. ) And spinner, carbon tetrachloride 5ml, acetic acid 5m
1 was added. 472.2 mg of iodine (1.86 m) in the system
mol, 0.6 eq. ) And iodic acid 177.3 mg
An aqueous solution of (1.01 mmol, 0.3 eq.) Dissolved in 1 ml of water was added, and the mixture was refluxed for 3 hours. After allowing to cool, saturated saline and chloroform were added for liquid separation, and the aqueous layer was extracted with chloroform three times. A 10% aqueous sodium thiosulfate solution was added to this organic layer and then washed twice with water. The extract was washed with saturated saline, dried over anhydrous sodium sulfate. After the desiccant was filtered off by suction filtration, the solvent was distilled off under reduced pressure, and the residue was purified by flash column chromatography to obtain compound (1-4) (light yellow liquid). Yield 416.1 mg (1.20 mmol), yield 38%.

¹ H NMR (270 MHz, CDCl ₃ , TMS) δ / ppm;
1.60 (3H, d, J / Hz = 6.59), 3.43 (3H, s), 4.64 (2H, d
d, J / Hz = 13.69, 6.76), 5.28 (1H, q, J / Hz = 6.49), 7.33
~ 7.46 (2H, m), 7.76 (2H, dd, J / Hz = 10.89, 7.59) IR (KRS-5, neat) ν / cm ^-1 ; 3057, 2977, 2946, 2928,
2866, 1433, 1096, 1028, 752

Synthesis of Compound (1-5) The compound (1
-4) 3.50 g (10.1 mmol, 1.0 eq.)
A spinner was added, the system was replaced with nitrogen, and 100 ml of tetrahydrofuran was added. Cool to −76 ° C., n-butyllithium 1.59 mol · dm ⁻³ hexane solution 14.
0 ml (22.3 mmol, 2.2 eq.) Was added to give 3
Stir for 0 minutes. Octafluorocyclopentene (3.0 ml, 22.4 mmol, 2.2 eq.) Was added dropwise thereto, and the mixture was stirred overnight while gradually returning to room temperature. After water was added to the system, ethyl acetate was added to separate the layers, and the aqueous layer was extracted 3 times with ethyl acetate. The obtained organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and the desiccant was removed by suction filtration. The solvent was evaporated under reduced pressure and the residue was purified by flash column chromatography to give compound (1
-5) (yellow liquid) was obtained. Yield 3.55 g (8.57)
mmol), yield 85%.

¹ H NMR (270 MHz, CDCl ₃ , TMS) δ / ppm;
1.60 (3H, d, J / Hz = 6.26), 3.35 (3H, s), 4.56 (2H,
s), 4.97 (1H, q, J / Hz = 6.49), 7.39 ~ 7.50 (3H, m), 7.
85〜7.89 (1H, m) IR (KRS-5, neat) ν / cm ⁻¹ ; 3066, 2983, 2937, 2928,
2891, 1711, 1393, 1276, 1158, 974 LRMS (EI, 70eV) m / z (rel intensity); 414 (M ⁺ , 22),
413 ((MH) ⁺ , 100), 353 ((MC ₂ H ₅ O ₂ ) ⁺ , 74)

Synthesis of (diarylethene 1) 3-iodo-2-methylbenzo [b] thiophene 752.3 mg (2.74 mmo) in a 100 ml two-necked flask.
1, 1.0 eq. ) And a spinner were added, the system was replaced with nitrogen, and 25 ml of tetrahydrofuran was added. The mixture was cooled to -76 ° C, and n-butyllithium 1.6 mol · dm ^-3 hexane solution 5.00 ml (8.00 mmol, 2.9e).
q. ) Was added and stirred for 40 minutes. On the other hand, in a 50 ml pear flask, 1.04 g (2.51 m) of compound (1-5)
mol, 0.9 eq. ) And a spinner were added, the system was replaced with nitrogen, and 20 ml of tetrahydrofuran was added with a syringe. This solution was slowly dropped into the above solution and stirred overnight while gradually returning to room temperature. Water and ethyl acetate were added to the system for liquid separation, and the aqueous layer was extracted 4 times with ethyl acetate. The collected organic layers were washed with saturated brine, dried over anhydrous sodium sulfate, and the desiccant was removed by suction filtration. The solvent was evaporated under reduced pressure and the residue was purified by flash column chromatography to give (diarylethene 1).
(Colorless solid) was obtained. Yield 497.6 mg (0.92 m
mol), yield 37%.

¹ H NMR (270 MHz, CDCl ₃ , TMS) δ / ppm;
0.23 (3H, d, J / Hz = 6.59 (ap)), 1.00 (3H, d, J / Hz = 6.
27 (p)), 1.45 (3H, d, J / Hz = 6.26 (ap)), 1.53 (3H,
d, J / Hz = 6.60 (p)), 2.06 (3H, s (ap)), 2.11 (3H, s
(p)), 2.64 (3H, s (ap)), 2.70 (3H, s (p)), 3.35
(3H, s), 4.43 (2H, dd, J / Hz = 15.84, 6.60), 4.73 (1H,
q, J / Hz = 6.38), 7.10 ~ 7.48 (4H, m), 7.59 ~ 7.89 (4H,
m) (parallel to the aromatic ring (parallel; p) and anti-paralle
l; ap) rotational isomers are observed, resulting in a complicated spectrum) IR (KBr-disk) ν / cm ^-1 ; 3064, 2986, 2949, 2892, 14
36, 1275, 1148, 1029,751 LRMS (EI, 70eV) m / z (rel intensity), 542 (M ⁺ , 29),
541 ((MH) ⁺ , 100), 481 ((MC ₂ H ₅ O ₂ ) ⁺ , 42), 453 ((M-
C ₄ H ₉ O ₂ ) ⁺ , 34) Melting point; 140-142 ° C

Example 2 (Diarylethene 2) was synthesized by the following reaction.

[Chemical 18]

The compound (2-
1) 983.9 mg (2.84 mmol, 1.0e)
q. ) And spinner, and nitrogen substitution in the system, THF2
5 ml was added. The flask was cooled to -78 ° C and n
2.71 ml (4.22 mmol, 1.5 eq.) Of butyllithium 1.56 mol · dm ⁻³ hexane solution was added with a syringe, and the reaction system was stirred for 1 hour while being kept at −78 ° C. Meanwhile, the compound (2-2) was added to a 50 ml flask.
944.5 mg (2.77 mmol, 1.0 eq.) And a spinner were added, the system was replaced with nitrogen, and 20 ml of THF was added with a syringe. This solution was slowly dropped into the previously stirred solution with a canula, and the mixture was stirred overnight while gradually returning the temperature from −78 ° C. to room temperature. Water was added to the reaction system to terminate the reaction, ethyl acetate was added to separate the layers, and the aqueous layer was extracted 3 times with ethyl acetate. The obtained organic layer was washed with saturated brine, anhydrous sodium sulfate was added and the mixture was stirred overnight, and then this was removed by suction filtration. The solvent was distilled off on a rotary evaporator, the residue was purified by flash column chromatography, and recrystallized from hexane to obtain a white solid (diarylethene 2). Yield 2
21 mg (0.41 mmol), 16% yield.

¹ H NMR (270 MHz, CDCl ₃ , TMS) δ / ppm;
0.27 (3H, d, J / Hz = 6.27), 0.46 (3H, t, J / Hz = 7.43),
0.84 (3H, t, J / Hz = 7.42), 0.98 to 1.07 (2H, m), 1.39
(3H, d, J / Hz = 6.6), 1.44 to 1.54 (2H, m), 2.07 (3H,
s), 2.66 (2H, dd, J / Hz = 2.31, 7.91), 3.18 (2H, t, J /
Hz = 6.77), 4.35 (1H, dd, J / Hz = 6.35, 8.00), 7.32 to 7.4
6 (4H, m), 7.69 ~ 7.82 (4H, m)

Example 3 (Diarylethene 3) was synthesized by the following synthetic route.

[Chemical 19]

Synthesis of Compound (3-1) (Diarylethene 1) 23 in a 30 ml two-necked flask.
Put 4.7 mg (0.433 mmol) and spinner,
Tetrahydrofuran 10 ml was added. 5 mol there
-1.0 ml of dm ^-3 hydrochloric acid was added, and the mixture was refluxed for 12 hours. After allowing to cool, saturated saline and ethyl acetate were added for liquid separation, and the aqueous layer was extracted 3 times with ethyl acetate. The obtained organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and the desiccant was removed by suction filtration. The solvent was distilled off under reduced pressure, and the residue was purified by flash column chromatography to obtain compound (3-1) (colorless viscous liquid). Yield 215.9 mg (0.433 mmo
l), yield 100%.

¹ H NMR (270 MHz, CDCl ₃ , TMS) δ / ppm;
0.69 (3H, d, J / Hz = 6.26 (ap)), 1.13 (1H, s (ap)),
1.36 (3H, d, J / Hz = 6.27 (p)), 1.51 (3H, d, J / Hz = 6.27
(ap)), 1.60 (3H, d, J / Hz = 6.92 (p)), 1.99 (1H, s
(p)), 2.18 (3H, s (ap)), 2.24 (3H, s (ap)), 2.57
(3H, s (p)), 2.62 (3H, s (p)), 4.96 (1H, q, J / Hz =
5.94 (ap)), 5.03 (1H, q, J / Hz = 2.86 (p)), 7.04 to 7.1
9 (1H, m), 7.29 to 7.79 (7H, m) IR (nujol) ν / cm ^-1 ; 3413, 3069, 2927, 2526, 1435,
1340, 1273, 1148, 750LRMS (EI, 70eV) m / z (rel int
ensity); 498 (M ⁺ , 29), 497 ((MH) ⁺ , 100), 481 ((MH
O) ⁺ , 11), 453 ((MC ₂ H ₅ O) ⁺ , 12)

Synthesis of (diarylethene 3) Compound (3-1) 139.1 was placed in a 30 ml two-necked flask.
mg (0.279 mmol, 1.0 eq.) and a spinner were added, the system was replaced with nitrogen, and 5 ml of dichloromethane was added. It was cooled to 0 ° C. and 1.30 ml of isobutene (14.
5 mmol, 52 eq. ) Was added, and a catalytic amount of concentrated sulfuric acid was further added, and the mixture was stirred overnight while gradually returning to room temperature from 0 ° C. After 10% sodium hydrogencarbonate aqueous solution was added to make it neutral, saturated saline and dichloromethane were added for liquid separation, and the aqueous layer was extracted three times with dichloromethane. The obtained organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and the desiccant was removed by suction filtration. The solvent was distilled off under reduced pressure, and the residue was purified by flash column chromatography to obtain (diarylethene 3) as a colorless solid. Yield 69.4 mg (0.125 mmol), yield 45%.

¹ H NMR (270 MHz, CDCl ₃ , TMS) δ / ppm;
0.44 (9H, s (ap)), 1.10 (9H, s (p)), 1.36 (3H, d,
J / Hz = 6.60 (ap)), 1.59 (3H, d, J / Hz = 9.23 (p)), 2.04
(3H, s (ap)), 2.05 (3H, s (p)), 4.27 (1H, q, J / Hz
= 6.60 (ap)), 4.53 (1H, q, J / Hz = 6.49 (p)), 7.30 ~ 7.
51 (4H, m), 7.74 ~ 7.83 (4H, m) IR (KBr-disk) ν / cm ^-1 ； 3061, 2975, 2934, 1436, 13
44, 1274, 1146, 979,751 LRMS (EI, 70eV) m / z (rel intensity); 554 (M ⁺ , 10
0), 497 ((MC ₄ H ₉ ) ⁺ , 40), 481 ((MC ₄ H ₉ O) ⁺ , 80), 453
((MC ₆ H ₁₃ O) ⁺ , 26) Melting point; 131-134 ° C

Example 4 (Diarylethene 4) was synthesized by the following reaction.

[Chemical 20]

The compound (1-
4) 1.73 g (4.98 mmol, 1.0 eq.)
Put a spinner, replace the system with nitrogen, and replace with tetrahydrofuran.
50 ml was added. Cool to -76 ° C and n-butyllithium
Um 1.59mol ・ dm^{- 3} Hexane solution 6.9 ml
(10.96 mmol, 2.2 eq.) Was added and 30 minutes
It was stirred for a while. Octafluorocyclopentene 0.
5 ml (3.74 mmol, 1.5 eq.) Was added dropwise,
The mixture was stirred overnight while gradually returning to room temperature. Add water to the system
After that, ethyl acetate was added for liquid separation, and the aqueous layer was washed with ethyl acetate.
Extracted 3 times. The obtained organic layer was washed with saturated saline,
After adding anhydrous sodium sulfate and drying, suction the desiccant
Removed by filtration. The solvent was distilled off under reduced pressure and the residue was flushed.
Column chromatography, and
Ten 4) (colorless viscous liquid) was obtained. Yield 312.1
mg (0.506 mmol), yield 20%.

¹ H NMR (270 MHz, CDCl ₃ , TMS) δ / ppm;
0.18 (6H, d, J / Hz = 6.59), 3.35 (6H, s), 4.43 (4H,
m), 4.67 (2H, m), 7.35 ~ 7.50 (4H, m), 7.75 ~ 7.95 (4
H, m) IR (KBr-Disk) ν / cm ^-1 ; 3066, 2980, 2949, 2900, 14
40, 1265, 1150, 1029,750

Example 5 (Diarylethene 5) was synthesized by the following synthetic route.

[Chemical 21]

(5-1) 4-methylthiophene-2-c
Synthesis of arbaldehyde In a 200 ml two-necked eggplant-shaped flask, spinner and 3-methylthiophene 3.05 g (31.1 mmol, 1.0
eq), and after purging with nitrogen, tetrahydrofuran 1
00 ml was added. An n-butyllithium hexane solution (1.56 mol · dm ⁻³ ) was added at room temperature for 22.0 m.
1 (28.3 mmol, 1.1 eq) was added and stirred for 3 hours. Next, 2.74 g of dimethylformamide (3
7.5 mmol, 1.2 eq. ) Was added and the mixture was stirred for 1 hour, and saturated aqueous ammonium chloride solution was added to terminate the reaction. This was extracted 3 times with ethyl acetate, the organic layer was removed of water with saturated saline and anhydrous sodium sulfate, and then 4-methylthiophene-2-carbaldehyde was obtained by flash column chromatography (10% ethyl acetate / hexane). Yield 3.51 g as a mixture of regioisomers 3-methylthiophene-2-carbaldehyde (molar ratio 8: 2)
(21.8 mmol), yield 90%.

¹ H NMR (270 MHz, TMS, CDCl ₃ ) 4-methylthiophene-2-carbaldehyde: δ / ppm; 2.33 (3H, s), 7.36 (1H, s), 7.58 (1H, s),
9.87 (1H, s) 3-Methylthiophene-2-carbaldehyde: δ / ppm; 2.59 (3H, s), 6.97 (1H, d, J / Hz = 4.95), 7.64
(1H, d, J / Hz = 4.95), 10.05 (1H, s) IR (KRS-5, neat) λ / cm ^-1 ; 3085, 1668, 1434, 123
8, 1192, 1134

(5-2) Synthesis of 2-formylbenzothiophene A spinner and benzo [b] thiophene 3.26 g (24.3 mmol, 1.
0 eq. ) Was added and the atmosphere was replaced with nitrogen, and then 30 ml of tetrahydrofuran was added to bring the temperature to -23 ° C. Here, n-butyl lithium (28.3 mmol, 1.2 eq.) And tetramethylethylenediamine 3.85 g (33.1 mmo).
1, 1.3 eq. ) Was added, and the mixture was stirred at -23 ° C for 30 minutes. Then, 2.83 g of dimethylformamide (38.
4 mmol, 1.5 eq. ) Was added and stirred for 1 hour, and then water was added to terminate the reaction. This was extracted 3 times with ethyl acetate, the organic layer was dewatered with saturated brine and anhydrous sodium sulfate, and then the target compound was purified with flash column chromatography (20% ethyl acetate / hexane) to give 3.
73 g (23.0 mmol) was obtained with a yield of 95%.

¹ H NMR (270 MHz, TMS, CDCl ₃ ) δ / ppm;
7.43 (1H, t, J / Hz = 7.59), 7.50 (1H, t, J / Hz = 7.59),
7.88 (1H, d, J / Hz = 7.92), 7.93 (1H, d, J / Hz = 7.59),
8.01 (1H, s), 10.09 (1H, s) IR (KBr-disk) λ / cm ^-1 ； 1668, 1589, 1515, 1425, 13
20, 1255, 1221, 1134,988, 876, 847

(5-3) 2-hydroxymethylbenzothio
Synthesis of phene A spinner and sodium borohydride 1.04 g (27.5 mmol, 1.
2 eq. ), And nitrogen replacement, then ethanol 30m
1 was added and the temperature was raised to 0 ° C. Here, 3.72 g (22.9 mmol, 1.0e) of 2-formylbenzothiophene
q. The ethanol (10 ml) solution of) was added and stirred for 30 minutes, and then water was added to terminate the reaction. This was extracted 3 times with ethyl acetate, the organic layer was removed of water with saturated saline and anhydrous sodium sulfate, and then 3.73 g (22.7 mmol) of the desired product was obtained by flash column chromatography (20% ethyl acetate / hexane). ), And the yield was 99%.

¹ H NMR (270 MHz, TMS, CDCl ₃ ) δ / ppm;
1.93 (1H, t, J / Hz = 6.11), 4.94 (2H, d, J / Hz = 5.27),
7.22 (1H, s), 7.28-7.38 (2H, m), 7.72-7.75 (1H, m),
7.81-7.84 (1H, m) IR (KRS-5, nujor) λ / cm ^-1 ; 3085, 1668, 1434, 123
8, 1192, 1134

(5-4) 2-chloromethylbenzothiop
Synthesis of hene In a 300 ml two-necked eggplant-shaped flask, 1.70 g (10.4 g) of spinner and 2-hydroxymethylbenzothiophene
mmol, 1.0 eq) and triphenylphosphine 3.
After adding 60 g (13.7 mmol, 1.3 eq) and substituting with nitrogen, 15 ml of diethyl ether was added and dissolved. 2.39 g of carbon tetrachloride (15.5 mmo)
1, 1.5 eq. ) Was added and the mixture was stirred at room temperature for 1 week. The compound (5-4) was synthesized by flash column chromatography (20% ethyl acetate / hexane) in an amount of 1.34 g (7.32 mmol) and a yield of 71%.

¹ H NMR (270 MHz, TMS, CDCl ₃ ) δ / ppm;
4.87 (2H, s), 7.30 (1H, s), 7.32-7.38 (2H, m), 7.72
-7.82 (2H, m) IR (KBr-disk) λ / cm ^-1 ; 3053, 1456, 1430, 1256, 75
8, 700

(5-5) (2-bennzothienylmethyl) t
Synthesis of riphenylphosphonium chloride In a 100 ml pear-shaped flask, spinner and 2-chloromethylbenzothiophene 1.52 g (8.32 mmol,
1.0 eq. ) And triphenylphosphine 6.66 g
(25.4 mmol, 3.1 eq.) Was added, dissolved in 25 ml of benzene, and heated under reflux for 8 hours. The precipitated white solid was suction filtered, the solid was washed with benzene, and the collected filtrate was evaporated to dryness with an evaporator,
The operation of adding benzene and refluxing was repeated to obtain 3.19 g of the desired product in a yield of 86%.

¹ H NMR (270 MHz, TMS, CDCl ₃ ) δ / ppm;
6.06 (2H, d, J / Hz = 14.2), 7.27-7.36 (2H, m), 7.62-7.
67 (9H, m), 7.75-7.88 (9H, m) IR (KBr-disk) λ / cm ^-1 ； 3056, 1437, 1112, 763, 74
5, 719, 688

(5-6) 1- (2-benzothienyl) -2
Synthesis of-(4-methyl-2-thienyl) ethene In a 200 ml two-necked eggplant-shaped flask, spinner and (2-
After adding 1.53 g (3.44 mmol, 1.0 eq) of benzothienylmethyl) triphenylphosphonium chloride and performing nitrogen substitution, 100 ml of tetrahydrofuran was added and the temperature was raised to 0 ° C. 2.5 ml of n-butyllithium hexane solution (1.56 mol · dm ⁻³ ) is added here.
(3.90 mmol, 1.1 eq) was added and 1 was left at 0 ° C.
Stir for hours. At this time, the solution changed from colorless to red. 4 dissolved in 20 ml of tetrahydrofuran
530 mg (4.20 mmol, 1.2 eq) of a mixture containing -methylthiophene-2-carbaldehyde was added with a canola at a rate of 1 drop per second. After stirring overnight, water was added to terminate the reaction, and this was extracted with ethyl acetate three times.
After removing water from the organic layer with saturated saline and anhydrous sodium sulfate, it was subjected to 1- (2-benzothienyl) -2- (4-methyl-2-thienyl) ethene by flash column chromatography (3% dichloromethane / hexane). Yield 705 mg (2.75 mmo)
l), yield 80%.

¹ H NMR (270 MHz, TMS, CDCl ₃ ) 1- (2-benzothienyl) -2- (4-methyl-2-thienyl) ethene: δ / ppm; 2.33 (3H, s), 7.36 ( 1H, s), 7.58 (1H, s),
9.87 (1H, s) 1- (2-benzothienyl) -2- (3-methyl-2-thienyl) ethene: δ / ppm; 2.59 (3H, s), 6.97 (1H, d, J / Hz = 4.95 ), 7.64
(1H, d, J / Hz = 4.95), 10.05 (1H, s) IR (KBr-disk) λ / cm ^-1 ; 3013, 1456, 940, 838, 748,
724

(5-7) 3-methylbenzothieno [5 ',
Synthesis of 4 ′: 2,3] benzothiophene In a four-necked flask for photoreaction, a mixture containing spinner and 1- (2-benzothienyl) -2- (4-methyl-2-thienyl) ethene 705 mg (2.75 mmol) , 1.0
eq) and a small amount of iodine were added and dissolved in benzene. After irradiating with ultraviolet light for 15 hours using an ultra-high pressure mercury lamp,
A 10% aqueous thiosulfate solution was added, and the mixture was extracted 3 times with ethyl acetate. After removing water from the organic layer with saturated saline and anhydrous sodium sulfate, 370 mg (1.46) of the desired product was obtained by flash column chromatography (hexane).
mmol) and the yield was 53%.

¹ H NMR (270 MHz, TMS, CDCl ₃ ) δ / ppm;
3.05 (3H, s), 7.32 (1H, s), 7.45-7.47 (2H, m), 7.78
(1H, d, J / Hz = 8.58), 7.90 (1H, d, J / Hz = 8.25), 7.93
(1H, m), 8.81-8.84 (1H, m) IR (KBr-disk) λ / cm ^-1 ； 3080, 1442, 1377, 863, 77
5, 736

(5-8) 3-acetylbenzothiophene
In a 100 ml two-necked flask, a spinner and 4.18 g (31.4 mmol, 1.3 eq.) Of aluminum chloride were placed and the atmosphere was replaced with nitrogen. After adding 30 ml of nitrobenzene, the reaction vessel was cooled to about 10 ° C. Here, 2.21 g (28.1 mmol, 1.2 eq.) Of acetyl chloride.
Was added at a rate of 1 drop per second, and the mixture was stirred for 1 hour. 3.18 g of benzothiophene dissolved in 10 ml of nitrobenzene
(23.7 mmol, 1.0 eq.) Was added at a rate of 1 drop per second, and the mixture was stirred for 1 hour. Water, 5M hydrochloric acid and chloroform were added to separate the organic layer and the aqueous layer.
Extracted twice. After removing water from the organic layer with saturated saline and anhydrous sodium sulfate, 3.79 g (21.5 mmo) of 3-acetylbenzothiophene was obtained by flash column chromatography (20% ethyl acetate / hexane).
l), yield 91%.

¹ H NMR (270 MHz, TMS, CDCl ₃ ) δ / ppm;
2.66 (3H, s), 7.22 (1H, s), 7.39-7.53 (2H, m), 8.29
(1H, s), 8.77 (1H, d, J / Hz = 7.26) IR (KRS-5, neat) λ / cm ^-1 ； 3093, 1660, 1373, 1341

(5-9) 3- (1-hydroxyethyl) benz
Synthesis of othiophene A spinner and sodium borohydride (620 mg, 16.4 mmol, 1.
1 eq. ), And nitrogen replacement, then ethanol 30m
1 was added and the temperature was raised to 0 ° C. Here, 2.58 g (14.6 mmol, 1.0e) of 3-acetylbenzothiophene
q. ) In ethanol (10 ml) and stirred for 2 hours, and water was added to terminate the reaction. This was extracted three times with dichloromethane, the organic layer was dewatered with saturated saline and anhydrous sodium sulfate, and then 2.66 g (14.9 mmol) of the desired product was obtained by flash column chromatography (20% ethyl acetate / hexane). The yield was 102%.

¹ H NMR (270 MHz, TMS, CDCl ₃ ) δ / ppm;
1.67 (3H, d, J / Hz = 6.60), 1.88 (1H, br), 5.29 (1H,
q, J / Hz = 6.60), 7.32-7.43 (3H, m), 7.85-7.93 (2H, m) IR (KRS-5, neat) λ / cm ^-1 ； 3272, 2922, 1462, 1455,
742, 724 melting point; 61-63 ℃

(5-10) 3- (1-methoxymethoxy)
Synthesis of ethylbenzothiophene In a 200 ml two-necked flask, spinner and sodium borohydride (60%, oil) 513 mg (12.8 mm)
ol, 1.1 eq. ) Was added and the atmosphere was replaced with nitrogen. Tetrahydrofuran (100 ml) was added as a solvent, and the reaction vessel was heated to 0 ° C. in an ice bath. Here, 2.03 g (11.4 mmol, 1.0 eq.) Of 3- (1-hydroxyethyl) benzothiophene dissolved in 50 ml of tetrahydrofuran.
Was added at a rate of one drop per second using a canula. After stirring for 1 hour, 1.17 g of chloromethyl methyl ether (1
4.5 mmol, 1.3 eq. ) Was added using a syringe at a rate of 1 drop per second. The temperature was gradually returned to room temperature from 0 ° C., and the mixture was stirred overnight. The reaction was terminated by adding water, and ethyl acetate was further added to separate the organic layer and the aqueous layer, and the aqueous layer was extracted with ethyl acetate three times. The organic layer was dried over saturated saline and anhydrous sodium sulfate, and anhydrous sodium sulfate was removed by suction filtration. The solvent was distilled off with an evaporator, and the desired product was isolated by flash column chromatography at a yield of 1.64 g and a yield of 65%.

¹ H NMR (270 MHz, TMS, CDCl ₃ ) δ / ppm;
1.64 (3H, d, J / Hz = 6.60) [1.63 (3H, d, J / Hz = 6.60)],
3.40 (3H, s) [3.42 (3H, s)], 4.64 (2H, s) [4.66 (2
H, dd, J / Hz = 6.93, 19.79)], 5.18 (1H, q, J / Hz = 6.60)
[5.10 (1H, q, J / Hz = 6.60)], 7.36 (1H, s) [7.20 (1H,
s)], 7.29-7.41 (2H, m), 7.64-7.95 (2H, m) (The values in [] are the minor peaks due to the difference in conformation. Integral ratio major: minor = 2: 1) IR (KRS-5, neat) λ / cm ^-1 ; 2977, 2931, 2886, 1458,
1428, 1153, 1098,1032, 919, 763, 736

(5-11) 1- (3- (1-methoxymet
hoxy) ethylbenzo-2-thienyl) heptafluorocyclopente
Synthesis of ne In a 100 ml two-necked flask, spinner and 3- (1-methoxymethoxy) ethylbenzothiophene 1.54 g
(6.93 mmol, 1.0 eq.) Was added and the atmosphere was replaced with nitrogen. Tetrahydrofuran (30 ml) was added, and the reaction vessel was cooled to -23 ° C using a freezing agent. 5.0 ml of n-butyllithium (1.55 mol.dm- ³ hexane solution)
(7.75 mmol, 1.1 eq.) Was added at a speed of 1 drop per second using a syringe, and the mixture was stirred at -23 ° C for 1 hour. At this time, the solution changed from colorless to turbid red. Next, octafluorocyclopentene 4.74 g (22.4 mm
ol, 3.2 eq. ) Was added rapidly, and the mixture was stirred overnight while gradually returning to room temperature. At this time, the solution changed from a cloudy red color to a black color and then to a transparent red color. Water was added thereto to terminate the reaction, ethyl acetate was added thereto to separate an organic layer and an aqueous layer, and the aqueous layer was extracted with ethyl acetate three times. The organic layer was dried over saturated saline and anhydrous sodium sulfate, and anhydrous sodium sulfate was removed by suction filtration. Evaporate the solvent with an evaporator,
The target product was isolated by flash column chromatography in a yield of 1.51 g and a yield of 53%.

¹ H NMR (270 MHz, TMS, CDCl ₃ ) δ / ppm;
1.69 (3H, d, J / Hz = 6.93), 3.30 (3H, s), 4.49 (2H, d
d, J / Hz = 6.77, 24.25), 4.98 (1H, q, J / Hz = 6.71), 7.41
-7.48 (2H, m), 7.84-7.90 (1H, m), 8.13-8.18 (1H,
m) IR (KRS-5, neat) λ / cm ^-1 ; 2989, 2940, 2890, 1708,
1384, 1330, 1277, 1205, 1157, 1098, 1024, 975, 76
6, 736

(Diarylethene 5) 1- (3- (1-
methoxymethoxy) ethylbenzothiophen-2-yl) -2-
(3-methylbenzothieno [5 ', 4': 2,3] benzo-2-th
Synthesis of ienyl) perfluorocyclopentene (HE2) Spinner and 3-methylbenzothieno [5 ', 4': 2,3] benzothiophene 132m in a 30 ml two-necked flask.
g (0.793 mmol, 1.0 eq.) was added and the atmosphere was replaced with nitrogen. Tetrahydrofuran (10 ml) was added, and the reaction vessel was cooled to -23 ° C using a freezing agent. n-Butyl lithium (1.55 mol · dm ⁻³ hexane solution) 0.4
ml (0.620 mmol, 1.2 eq.) was added with a syringe at a speed of 1 drop per second, and the mixture was stirred for 1 hour at -23 ° C. At this time, the solution changed from colorless to blue. Next, 1- (3- (1
-Methoxymethoxy) ethylbenzo-2-thienyl) heptafluorocyclopentene 329 mg (0.793 m
mol, 1.5 eq. ) Was added using a canula at a rate of 1 drop per second, and the mixture was stirred overnight while gradually returning to room temperature. At this time, the solution changed from blue to yellow. Water was added thereto to terminate the reaction, ethyl acetate was added thereto to separate an organic layer and an aqueous layer, and the aqueous layer was extracted with ethyl acetate three times. The organic layer was dried over saturated saline and anhydrous sodium sulfate, and anhydrous sodium sulfate was removed by suction filtration. The solvent was distilled off with an evaporator, and the target product was isolated by flash column chromatography in a yield of 158 mg and a yield of 47%.

¹ H NMR (270 MHz, TMS, CDCl ₃ ) δ / ppm;
0.95 (3H, d, J / Hz = 6.60), 2.65 (3H, s), 3.22 (3H,
s), 4.31 (2H, dd, J / Hz = 6.60, 24.08), 4.98 (1H, q, J
/Hz=6.49), 7.28-7.46 (4H, m), 7.83 (2H, s), 7.90 (2
H, d, J / Hz = 7.26), 8.10 (1H, d, J / Hz = 7.92), 8.26 (1
H, d, J / Hz = 7.92) IR (KRS-5, nujor) λ / cm ^-1 ; 3061, 1558, 1458, 137
6, 1268, 1196, 1125,988, 899 MS (EI, 70 eV) m / z; 648 (M ⁺ , 84), 603 ((MC ₂ H ₅ O) ⁺ ,
18), 582 (100) .Found: m / z 648.0654.Calcd for C
₃₂ H ₂₂ F ₆ S ₃ O ₂ : M, 648.0686

Ring-opened form of diarylethene 5 (O of HE2
Optical resolution chiral column (Daicel Chemical Industries chiralpac OD-
H, φ10mm × 250mm, high performance liquid chromatography equipped with a preparative unit (liquid transfer unit: Shimadzu L)
C-6AD, UV-visible spectrophotometer detector: Shimadzu S
PD-10A, Chromatopack: Shimadzu C-R6
According to A), 0.5 v / v% 2-propanol / hexane was used as an eluent and fractionation was carried out at a flow rate of 2.0 ml · min ⁻¹ . 100 μl each of the synthesized 2-propanol saturated solution of O-form of HE2 was injected at a time. Moreover, in order to check the purity of the separated solution, a chiral column (Daicel Chemical Industries chiralpac OD-H, φ4.6 m
High-performance liquid chromatography equipped with m × 250 mm (for analysis) (liquid sending unit: Shimadzu LC-10A)
S, UV-visible spectrophotometer detector: Shimadzu SPD-1
0A, Chromatopack: Shimadzu C-R6A) using 0.5 v / v% 2-propanol / hexane as an eluent, and detection was performed at a flow rate of 0.5 ml · min ⁻¹ . The collected solution was almost pure.

Ring-closed product of diarylethene 5 (C of HE2
Body) synthesis HE2O optically split into a 500 ml Erlenmeyer flask
_slow(It comes out slowly by HPLC equipped with OD-H.
Component) 59.9 mg (0.0923 mmol) to 300
about 3 x 10 dissolved in ml ethyl acetate^-Fourmol · dm
^-3About 5 cm in diameter and 1 cm in cell thickness.
After adding 15 ml and irradiating with 405 nm light for 30 minutes, 50
It was collected in a 0 ml eggplant flask. Repeat this 20 times
Then, remove ethyl acetate with an evaporator and flush.
HE2C by column chromatography_{majo r}(C body two
Yield 21.5 of the major product of the two diastereomers)
mg, yield 36%.

¹ H NMR (270 MHz, TMS, CDCl ₃ ) δ / ppm;
1.01 (3H, d, J / Hz = 6.27), 2.72 (3H, s), 3.18 (3H,
s), 4.44 (2H, s), 5.26 (1H, q, J / Hz = 6.49), 6.12 (1
H, t, J / Hz = 7.76), 6.63 (1H, d, J / Hz = 6.92), 6.70 (1
H, t, J / Hz = 7.26), 7.03 (1H, t, J / Hz = 7.59), 7.19-7.
25 (2H, m), 7.27 (1H, d, J / Hz = 8.25), 7.37 (1H, d, J
/Hz=8.90),7.74 (1H, d, J / Hz = 7.26), 7.84 (1H, d, J /
Hz = 8.24) IR (KRS-5, nujor) λ / cm ^-1 ; 3061, 1634, 1463, 137
7, 1268, 1196, 1125,969, 722 MS (EI, 70 eV) m / z; 648 (M ⁺ , 2), 604 (100) .Found:
m / z 648.0724.Calcd for C ₃₂ H ₂₂ F ₆ S ₃ O ₂ : M, 648.0686

FIG. 1 shows the absorption spectrum of HE2O _fast , the photo steady state, and the calculated HE2C. HE2O
The absorption spectrum of Form C (41% diastereomer mixture) was calculated from the absorption spectrum when _fast was irradiated with 405 nm light to _bring it to a photosteady state. Further, the maximum absorption wavelength and the molar extinction coefficient of the O- and C-forms are shown below. The absorption spectra of the two diastereomers of Form C were assumed to be the same. Solvent: Toluene Concentration: 1.50 × 10 ⁻⁴ (mol · dm ⁻³ ) Absorption maximum wavelength: O-form 368 nm (ε = 14370 (mol · dm ⁻³ · cm ⁻¹ )) C-form 485 nm (ε = 4750 ( mol · dm ⁻³ · cm ⁻¹ ))

FIG. 2 shows HE2O _fast measured under the following conditions.
And the photoluminescence steady-state fluorescence spectrum are shown. Solvent: Toluene concentration: 1.50 × 10 ⁻⁴ (mol · dm ⁻³ ) Excitation light: 405 nm

FIG. 3 shows HE2O _fast and HE calculated.
2C shows the respective absorption spectrum and fluorescence spectrum of 2C. The fluorescence spectrum of the C-form was calculated from the fluorescence spectrum when HE2O _fast was irradiated with 405 nm light and brought into a photosteady state. However, it was assumed that the fluorescence spectra of the two diastereomers of the C form were the same.

Example 6 1.40 × 10 ^{−4 of} diarylethene 1 obtained in Example 1
An n-hexane solution, a toluene solution, and an ethyl acetate solution having a concentration of mol · dm ⁻³ were prepared, and each solution was irradiated with 313 nm light at room temperature to make a photo steady state. As an example, FIG. 5 shows the absorption spectrum change of a hexane solution.
The change in spectrum is shown in FIG. Further, the conversion rate of the photochromic reaction in each solvent and the rate of asymmetric induction (diastereomeric excess rate) at this time were measured by high performance liquid chromatography. The results are shown in Table 1.

[0084]

[Table 1]

In three solvents having different polarities, the photochromic reaction proceeds at a conversion rate of 80% or more in any of the solvents, and the diastereoselectivity associated with photochromism proceeds with a high selectivity of about 90%. It was possible. In the case of the following compounds described in JP-A-9-77767, the conversion rate of the photochromic reaction from the ring-opened compound to the ring-closed compound at room temperature is 42.5%, and the diastereomer excess rate at this time is 0%. In a toluene solution, the diastereomeric excess at room temperature was 72% and the conversion was about 10% (M. Irie, et a
l., J. Am. Chem. Soc., 119, 6066 (1997)), the usefulness of the diarylethene compounds of the present invention is clear.

[0086]

[Chemical formula 22]

In addition, (M. Irie, et al., J. Am. Chem.
The following compounds described in Soc., 122, 9631 (2000)) show asymmetric induction only in a single crystal, and thus the position of introducing asymmetric carbon in the diarylethene compound of the present invention (adjacent position of carbon atoms to be cyclized) ) Is clearly useful.

[0088]

[Chemical formula 23]

Since the photochromic reaction proceeds with such high diastereoselectivity, it is possible to observe a reversible change in the CD spectrum without the need to isolate two types of ring-closed compounds having a diastereomeric relationship. there were.

Example 7 An n-hexane solution of the diarylethene 1 obtained in Example 1 was prepared, and the change in the specific optical rotation at 820 nm was measured between the ring-opened product and the photosteady state of 313 nm light irradiation (measurement). Conditions; concentration: 0.502 g / L, temperature: 30 ° C., cell length: 10 cm). +1 for ring-opened diarylethene 1
It was 44 °, and it changed to + 50 ° when irradiated with 313 nm, and it was confirmed that the optical rotation reversibly changed with the photochromic reaction. Therefore, when applied to a recording medium, it is possible to read the recording nondestructively.

Example 8 1.50 × 10 ^{−4 of} diarylethene 5 obtained in Example 5
mol · dm ⁻³ solution (solvent: n-hexane, toluene,
(Methanol, ethyl acetate) was irradiated with 405 nm light at room temperature to make a photo steady state. The ratio of the ring-opened compound (O) and the ring-closed compound (C: two diastereomers), the conversion rate and the ratio of asymmetric induction (diastereomeric excess rate) of the photochromic reaction in each solvent were measured by high performance liquid chromatography. It was measured at. The results are shown in Table 2.

[0092]

[Table 2]

Among the three solvents having different polarities, the photochromic reaction proceeds at a conversion rate of 60% or more in any of the solvents, and the diastereoselectivity associated with photochromism is allowed to proceed with a selectivity of about 40%. Was possible. In the case of the compound described in JP-A-9-77767, the conversion rate of the photochromic reaction from the ring-opened compound to the ring-closed compound at room temperature is 42.5%, and the diastereomeric excess rate at this time is 0%. , In a toluene solution,
The diastereomeric excess at room temperature was 72% and the conversion was about 10% (M. Irie, et al.,
J. Am. Chem. Soc., 119, 6066 (1997).), The usefulness of the diarylethene compounds of the present invention is clear.

In addition, (M. Irie, et al., J. Am. Chem.
Soc., 122, 9631 (2000).), The asymmetric induction is observed only in a single crystal, and the asymmetric carbon introduction position in the diarylethene compound of the present invention (adjacent carbon atoms to be cyclized) Position) is clear.

Example 9 1.50 × 10 ^{−4 of} diarylethene 5 obtained in Example 5
mol · dm ⁻³ solution (solvent: n-hexane, toluene,
Specific rotation [α] _D of the ring-closed compound (methanol, ethyl acetate) at room temperature at a wavelength of 589 nm and 405 nm at room temperature.
Light was irradiated to make a photo steady state, and the specific optical rotation [α] _D at the wavelength of 589 nm in the photo steady state was measured. The results are shown in Table 3.

[0096]

[Table 3]

It was observed that the optical rotation was large and reversibly changed with the photochromic reaction. Therefore, when applied to a recording medium, it is possible to read the recording nondestructively.

Example 10 1.50 × 10 ⁻⁴ mol of HE 2 O _fast obtained in Example 5
-A toluene solution having a dm ^-3 concentration was prepared and a CD spectrum was measured. A CD spectrum in a photosteady state obtained by irradiating this with light of 405 nm was measured. The results are shown in Fig. 4. Dispersion of the CD spectrum based on the ring-closed diarylethene 5 was observed at a wavelength of 300 nm to 450 nm.
It is not found in the ring-opened form of diarylethene 5, and when it is applied to a recording medium, it is possible to read the record by detecting the presence or absence of circular dichroism.

Example 11 Preparation of Photochromic Recording Material A film was prepared by dispersing the diarylethene 1 synthesized in Example 1 in a polymer medium. A film medium having a film thickness of 83.5 μm in which diarylethene 1 was dispersed at a concentration of 6.1% by weight with respect to polymethylmethacrylate by a casting method using dichloromethane as a solvent was prepared. When this film medium was irradiated with ultraviolet light (313 nm light), the exposed area was colored red. When visible light (> 470 nm light) is irradiated on the reddish region, it is observed that the exposed region changes to colorless again, the photochromic reaction is not suppressed even in the polymer medium, and this conversion can be repeated many times. It was possible. Similar reversible color changes were observed upon irradiation of crystals of diarylethene 1 with light.

The change in optical rotation at 820 nm was measured with repeated irradiation of ultraviolet light and visible light on the film medium. The results are shown in Fig. 7. It was confirmed that the optical rotation reversibly changed with repeated irradiation of ultraviolet light and visible light. Light having a wavelength of 820 nm is not absorbed by the diarylethene 1, and the optical rotation is greater near the absorber, so that information is written to the medium by light having a wavelength of 313 nm, and the optical rotation (or the optical rotation at a wavelength of 650 nm or more that does not absorb light). It can be applied to a recording medium that reads out (refractive index) and erases information with light having a wavelength of 400 to 650 nm. Further, since the diarylethene 1 exhibits a photochromic reaction not only in a solution but also in a polymer medium, it can be applied to an optical element such as a color display medium rewritable by light, a light control material and a light modulation element.

Example 12 Preparation of Photochromic Recording Material A film was prepared in which the diarylethene 5 synthesized in Example 5 was dispersed in a polymer medium. A film medium having a film thickness of 78 μm in which diarylethene 5 was dispersed at a concentration of 5% by weight with respect to polymethylmethacrylate by a casting method using dichloromethane as a solvent was prepared. When this film medium was irradiated with ultraviolet light (405 nm light), the exposed area was colored red. When visible light (> 470 nm light) is irradiated on the reddish region, it is observed that the exposed region changes to colorless again, the photochromic reaction is not suppressed even in the polymer medium, and this conversion can be repeated many times. It was possible. When a crystal of diarylethene 5 was irradiated with light, the same reversible color change was observed.

As a result of measuring the change in optical rotation at 589 nm with repeated irradiation of ultraviolet light and visible light on the above film medium, the optical rotation reversibly changes with repeated irradiation of ultraviolet light and visible light. Things were confirmed. Since the diarylethene 5 has a larger optical rotation near the absorber, for example, information is written in the medium with light having a wavelength of 405 nm, optical rotation (or refractive index) is read at a wavelength of 470 nm or more without absorption, and a wavelength of 450 to 550 nm is used. It can be applied to a recording medium in which information is erased by the light. Further, since the diarylethene 5 exhibits a photochromic reaction not only in a solution but also in a polymer medium, it can be applied to an optical element such as a color display medium rewritable by light, a light control material, and a light modulation element.

[0103]

INDUSTRIAL APPLICABILITY In the present invention, by making asymmetrical carbon atoms adjacent to the photocyclizing carbon atom of the diarylethene-based molecule, their photochromic reaction characteristics and diastereoselectivity are not affected by the properties of the medium, It is possible to highly selectively control the configuration of two carbon atoms in the colored body formed by the photocyclization reaction. Therefore, it can be applied to a recording medium or the like utilizing changes in optical rotation and refractive index.

[Brief description of drawings]

FIG. 1 is a diagram showing an absorption spectrum of HE2O _fast and a photo steady state obtained in Example 5, and HE2C obtained by calculation.

FIG. 2 is a diagram showing a fluorescence spectrum of HE2O _fast obtained in Example 5 and a photosteady state.

FIG. 3 is a diagram showing absorption and fluorescence spectra of HE2O _fast obtained in Example 5 and HE2C calculated.

FIG. 4 is a diagram showing a change in CD spectrum associated with photochromism in HE2O _fast and a photosteady state in Example 10.

5 is a diagram showing a change in absorption spectrum of diarylethene 1 obtained in Example 1. FIG.

FIG. 6 is a diagram showing a change in CD spectrum of diarylethene 1 obtained in Example 1 with photochromism.

FIG. 7 is a diagram showing a change in optical rotation with light irradiation to a polymethylmethacrylate film in which diarylethene 1 obtained in Example 1 is dispersed.

Continued front page    (31) Priority claim number Japanese Patent Application No. 2002-54264 (P2002-54264) (32) Priority date February 28, 2002 (February 28, 2002) (33) Priority claiming country Japan (JP) (72) Inventor Toshiya Kosaka             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh (72) Inventor Yasushi Yokoyama             6-14 Hiyoshihonmachi, Kohoku-ku, Yokohama-shi, Kanagawa             No. 7 (72) Inventor Tomoyuki Okuyama             337-22 Inume-cho, Hachioji-shi, Tokyo F-term (reference) 2H123 AA00 AA10                 4C071 AA01 BB01 BB06 CC22 EE13                       FF23 GG03 JJ01 JJ07 KK14                       LL05

Claims (5)

[Claims] 1. A compound represented by the following general formula (I):
, A, B and C are different substituents, respectively.
A characteristic diarylethene-based photochromic compound. [Chemical 1] (In the general formula (I), X and Y represent an aromatic ring. R¹Is
A, B, and C each represent a substituent having an asymmetric carbon atom,
A, B and C are each a hydrogen atom, a halogen atom,
And an optionally substituted alkyl group, an alkoxy group,
Alkoxycarbonyl group, alkoxycarbonyloxy
Group, represents three different groups selected from aryl groups
Or A, B and C are joined together to form a ring
May be. R ²Is R¹May be the same as or different from
In this case, an optionally substituted alkyl group, ar
Coxy group, acyl group, amino group, alkoxycarbonyl
Group, aryloxy group, aryl group, carbamoyl group,
Represents a nitro group, a cyano group and a halogen atom. R³and
R^FourMay be the same or different, and may be hydrogen atom, halogen
Atom, alkyl group, alkoxy group, acyl group, amino
Group, alkoxycarbonyl group, aryloxy group, ant
Group, carbamoyl group, nitro group, cyano group
Or R³And R^FourCombine with each other to form a ring
Also, in that case, an acid anhydride group, an imide group, a substituted
Represents an optionally substituted alkyl group. ) 2. In the general formula (I), X and Y
Is a 5-membered or 6-membered heteroaromatic ring composed of atoms selected from carbon, sulfur, nitrogen, oxygen, and selenium, The diarylethene-based photochromic compound according to claim 1. 3. In the above general formula (I), X and Y
Is a substituted or unsubstituted thiophene ring, The diarylethene photochromic compound according to claim 1 or 2, wherein 4. A photochromic material comprising the diarylethene-based photochromic compound according to claim 1. 5. An optical element comprising the diarylethene-based photochromic compound according to claim 1. Description: