CN1439639A - Bipyridine diaryl ethylene compounds and preparation and application thereof - Google Patents

Abstract

The name of the present invention is bipyridyl diarylethene compound and its preparation method and application, relates to organic photochromic material and its manufacture method and application, especially relates to a kind of organic photochromic diarylene compound and its Manufacturing methods and applications. The present invention provides a compound composed of structural units of formula (I) with a molecular weight of 732.8-7328: wherein, R is an oligopyridine compound of 2-5; n is an integer of 1-10. The compound of the invention can be widely used as an optical information storage material, as a photochromic molecular device, and can also be applied in the preparation of a photochromic light-emitting device.

Description

Bipyridyl diarylethene compound and its preparation method and application

technical field

The invention relates to an organic photochromic material and its manufacturing method and application, in particular to a class of organic photochromic diarylethene compounds and its manufacturing method and application.

Background technique

Since Philips launched the laser video disk system LD in the 1970s, the optical disk storage technology and the optical disk industry have achieved tremendous development. Organic write-once CD-R discs recorded using the photothermal effect have become a mainstream product, and due to its low cost, the usage in the world is growing rapidly. At the same time, CD-RW optical discs that can be rewritten multiple times based on the principle of phase change have also been rapidly developed, but this type of optical disc also has certain limitations, such as relatively expensive price, long writing and erasing time, and limited storage density. With the rapid development of computer technology, the requirements for optical information storage technology and materials are getting higher and higher.

In recent years, photochromic molecules have made great progress in the application of optical information storage materials. The so-called photochromic phenomenon refers to the reversible transformation of a chemical substance between two states with significantly different absorption spectra, in which at least one direction transformation is caused by electromagnetic radiation. Molecules with this characteristic are called as photochromic molecules. During photoisomerization, not only the absorption spectrum of such molecules changes, but also changes such as their refractive index, dielectric constant, oxidation/reduction potential, and geometric configuration. The change of these properties can be practically used in the preparation of various optoelectronic devices, such as rewritable optical information storage materials and optical control switching elements. However, some photochromic molecules such as azobenzene, spiropyran, and fumaric anhydride generally have disadvantages such as poor thermal stability or poor thermal and light fatigue resistance, and it is difficult to use them as photonic information storage materials. .

The ring-opening and ring-closing states of diarylethene photochromic compounds have good thermal stability, remarkable fatigue resistance, and high cyclization quantum yield and sensitivity. The cyclization/ring-opening The reaction cycle is repeated more than 10 ⁴ times and can maintain good photochromic performance, which is an ideal high-density photon storage, rewritable optical storage material and optical control switch material.

Contents of the invention

The object of the present invention is to provide a new type of photochromic compound—bipyridyl diarylethene compound.

The bipyridyl diarylethene compound provided by the present invention is composed of structural units of formula (I) and has a molecular weight of 732.8-40000:

Wherein, R is an oligopyridine compound of 2-6; n is an integer of 1-60.

It is preferred that R is bipyridine or terpyridine; n is an integer of 1-60.

当R＝5，5′-二甲基-2，2′-双联吡啶，n＝1时，本发明化合物的结构式为：

当R＝5，5′-二甲基-2，2′-双联吡啶，n＝2-60时，本发明化合物的结构式为：

For example, when R=4,4'-dimethyl-2,2'-bipyridine, n=1, the structural formula of the compound of the present invention is: When R=4,4'-dimethyl-2,2'-bipyridine, n=2-60, the structural formula of the compound of the present invention is:

When R=5,5'-dimethyl-2,2'-bipyridine, n=1, the structural formula of the compound of the present invention is:

When R=5,5'-dimethyl-2,2'-bipyridine, n=2-60, the structural formula of the compound of the present invention is:

Another object of the present invention is to provide a kind of method of producing bipyridyl diarylethene compound, this method, basically consists of the following steps:

1) 2-dimethylthiophene is reacted with liquid bromine in an ice bath in acetic acid to obtain 3,5-dibromo-2-methylthiophene;

2) 3,5-dibromo-2-methylthiophene was dissolved in anhydrous ether, injected into n-BuLi, and tributyl borate was added to obtain 2-methyl-3-bromo-5-boronic acid thiophene;

3) Dissolve bromobipyridine and Pd(PPh ₃ ) ₄ in tetrahydrofuran, and add 2-methyl-3-bromo-5-boronic acid thiophene with stirring to obtain 2-bipyridine-4-bromo-5-methyl Thiophene;

4) Low-temperature reaction of 2-bipyridine-4-bromo-5-methylthiophene with n-BuLi and perfluorocyclopentene to obtain the desired product.

In the above method, when the ratio of the reactant is brominated bipyridine: 2-methyl-3-bromo-5-boronic acid thiophene: perfluorocyclopentene=2:2:1, what is obtained is the bipyridine bis Aryl vinyl compound monomer.

In the above method, when the ratio of the reactant is dibromobipyridine: 2-methyl-3-bromo-5-boronic acid thiophene: perfluorocyclopentene=1:2:1, what is obtained is a chain high molecular compound.

Bipyridyl diarylethene compounds are a new class of photochromic compounds. Under the action of ultraviolet/visible light, this type of compound undergoes a photochromic reaction in the closed-ring/opening mode. The open-ring state and the closed-ring state have good thermal stability, and this closed-ring/opening cycle has very good fatigue resistance Therefore, this type of compound has broad prospects in optical information storage, and can realize molecular storage. Its advantages are high storage density, high sensitivity, low price, good diamagnetic performance, and easy modification.

The main uses of the bipyridyl diarylethene photochromic compound of the present invention are: doping polymer materials or making membranes, which can be matched with 650nm lasers, as optical information storage materials; used to prepare optical control switch elements; Used in the preparation of photochromic light-emitting devices; used in the preparation of ultra-high density rewritable organic optical discs, etc.

The application of the present invention is based on the following molecular properties:

1. This bipyridyl diarylethene photochromic compound can maintain good photochromic performance in solution or film, and both the open-ring state (colorless state) and the closed-ring state (colored state) have excellent photochromic properties. Excellent chemical and thermal stability, remarkable fatigue resistance, high cyclization quantum yield and good sensitivity and other superior properties. Chain polymer compounds further enhance its performance.

2. Due to the introduction of bipyridyl side groups, the degree of conjugation increases and the absorption wavelength red shifts. The absorption spectrum of the colored state is located at 600-700nm, which can be matched with a 650nm laser, and is used for high-density organic photochromic optical information storage media.

Embodiments of the present invention will be further described below in conjunction with the accompanying drawings.

Description of drawings

Fig. 1 is compound 1,2-bis(2-methyl-5-(4,4'-dimethyl bipyridin-5-yl)-thiophen-3-yl) perfluorocyclopentene in PMMA film UV Absorption spectra before and after light irradiation

Detailed ways

Embodiment 1, the synthesis of 1,2-bis(2-methyl-5-(4,4'-dimethyl bipyridin-5-yl)-thiophen-3-yl) perfluorocyclopentene

synthetic route:

Concrete synthetic steps are as follows:

1. Preparation of 3,5-dibromo-2-methylthiophene

Dissolve 8 grams of 2-dimethylthiophene in 33.4 milliliters of glacial acetic acid, and install a constant-pressure dropping funnel with 9.6 milliliters of liquid bromine and 14 milliliters of glacial acetic acid. After Na ₂ CO ₃ was neutralized, it was extracted with ether, the organic phases were combined, washed with Na ₂ CO ₃ aqueous solution, dried overnight, filtered, solvent removed, and 8.5 ml of light yellow liquid 3,5-dibromo- 2-Methylthiophene.

Yield: 82%.

Structural identification: IR (cm ^-1 ) 780.4, 810.1, 949.8, 1010.5, 1138.8, 1301.7, 1450.9, 1535.8, 2785.8, 3080.9. Prove that the obtained result is correct.

2. Preparation of 2-methyl-3-bromo-5-boronic acid thiophene

At -78°C, dissolve 6 g of 3,5-dibromo-2-methylthiophene in 100 ml of anhydrous ether, stir, slowly inject 14.6 ml of 1.6Mn-BuLi, half an hour later, add 7 ml For tributyl borate, the temperature was naturally raised to continue the reaction for 1.5 hr. After that, dilute hydrochloric acid was added to stop the reaction, the liquid was separated, and the water phase was discarded. Extract with aqueous sodium hydroxide solution, discard the organic phase, and acidify the aqueous phase with dilute hydrochloric acid solution until it is neutral and white precipitate no longer occurs. After filtration, the precipitate was washed with dilute hydrochloric acid, and dried in vacuo to obtain 3.2 g of light yellow solid 2-methyl-3-bromo-5-boronic acid thiophene.

Yield: 62%.

Structural identification: IR (cm ^-1 ) 690.0, 789.9, 832.3, 1009.9, 1132.4, 1340.3, 1473.5, 1528.3, 1290.8, 3201.5. Prove that the obtained result is correct.

3. Preparation of 2-bipyridine-4-bromo-5-methylthiophene

7.9 g of bromobipyridine and 1 g of Pd(PPh ₃ ) ₄ were dissolved in 60 mL of tetrahydrofuran (THF), and 6.6 g of 2-methyl-3-bromo-5-borothiophene and 30 mL of 2M Na ₂ CO ₃ aqueous solution, heated to reflux for 16hr., then stopped the reaction, cooled to room temperature, separated the liquid, extracted the aqueous phase with ether, combined the organic phase, evaporated the solvent by rotary evaporation, dried in vacuo, separated and purified by column chromatography to obtain 7.7 g of light yellow 2- Bipyridine-4-bromo-5-methylthiophene.

Yield: 72%.

Structural identification: ¹ HNMR (400MHz, CDCl ₃ ): δ2.21(3H), δ2.28(3H), δ2.45(3H), δ6.73(1H), δ7.02(1H), δ7.09 (1H), δ7.34(1H), δ7.82(1H), δ8.41(1H). Prove that the obtained result is correct.

4. Preparation of 1,2-bis(2-methyl-5-(4,4'-dimethylbisbipyridin-5-yl)-thiophen-3-yl)perfluorocyclopentene

Under nitrogen and -78°C, 3.80 g of 2-bipyridine-4-bromo-5-methylthiophene was dissolved in 60 ml of THF, and 8.75 ml of 1.6M n-BuLi in hexane was added with stirring. 0.72 ml of perfluorocyclopentene was added into the reaction flask, and the reaction mixture was stirred at low temperature for 2 hr. After that, it was naturally raised to room temperature, and an appropriate amount of water was added to terminate the reaction. Separation, extraction with ether, combined organic phases, solvent removal, vacuum drying, and column chromatography to obtain 4.74 grams of 1,2-bis(2-methyl-5-(4,4'-dimethylbisbipyridine-5- base)-thiophen-3-yl)perfluorocyclopentene product.

Yield: 61%.

Structural identification: ¹ HNMR (400MHz, CDCl ₃ ): δ2.20(6H), δ2.26(6H), δ2.38(6H), δ6.70(2H), δ6.86(2H), δ7.05 (2H), δ7.38 (2H), δ7.64 (2H), δ8.40 (2H). Prove that the obtained result is correct.

As shown in Figure 1, for 1,2-bis(2-methyl-5-(4,4'-dimethyl bipyridin-5-yl)-thiophen-3-yl) perfluorocyclopentene in The absorption spectrum diagrams before and after ultraviolet light irradiation, in the figure, the solid line is the absorption spectrum diagram before ultraviolet light irradiation; the dotted line is the absorption spectrum diagram after ultraviolet light irradiation, as can be seen from the figure, the absorption spectrum of the compound is in the color state Located at 610nm, it can be used for high-density organic photochromic optical information storage media.

Example 2, 1,2-bis(2-methyl-5-(4,4'-dimethyl bipyridin-5-yl)-thiophen-3-yl) perfluorocyclopentene chain polymer compound synthesis

synthetic route:

Concrete synthetic steps are as follows:

1, prepare 3,5-dibromo-2-methylthiophene (with embodiment 1)

2. Preparation of 2-methyl-3-bromo-5-boronic acid thiophene (same as Example 1)

3. Preparation of 5,5'-bis(3-bromo-2-methylthiophen-5-yl)-4,4'-dimethylbisbipyridine

Dissolve 8.2 g of bromobipyridine and 1 g of Pd(PPh ₃ ) ₄ in 60 mL of tetrahydrofuran (THF), stir, and add 6.0 g of 2-methyl-3-bromo-5-boronic thiophene and 40 mL of 2M The Na ₂ CO ₃ aqueous solution was heated to reflux for 20hr. After that, the reaction was stopped, cooled to room temperature, separated, the aqueous phase was extracted with ether, the organic phase was combined, the solvent was evaporated by rotary evaporation, dried in vacuo, and purified by column chromatography to obtain 6.2 g of light yellow 2 - Bipyridine-4-bromo-5-methylthiophene.

Yield: 62%.

Structural identification: ¹ HNMR (400MHz, CDCl ₃ ): δ 2.26 (6H), δ 2.45 (6H), δ 7.34 (2H), δ 7.81 (2H), δ 7.05 (2H). Prove that the obtained result is correct.

4. Preparation of 1,2-bis(2-methyl-5-(4,4'-dimethyl bipyridin-5-yl)-thiophen-3-yl) perfluorocyclopentene chain polymer compound

Dissolve 4.6 g of 5,5'-bis(3-bromo-2-methylthiophen-5-yl)-4,4'-dimethylbisbipyridine in 60 ml of THF under nitrogen at -78°C , stirred and added 16 ml of 1.6M n-BuLi hexane solution, added 1.2 ml of perfluorocyclopentene into the reaction flask, and continued to stir the reaction mixture at low temperature for 2hr. After that, it naturally rose to room temperature, and added an appropriate amount of Water terminates the reaction. Separation, extraction with ether, combined organic phases, solvent removal, vacuum drying, and column chromatography to obtain 5.6 grams of 1,2-bis(2-methyl-5-(4,4'-dimethylbisbipyridine-5- base)-thiophen-3-yl) perfluorocyclopentene chain polymer compound.

Yield: 61%.

Structural identification: ¹ HNMR (400MHz, CDCl ₃ ): δ2.25(6H), δ2.43(6H), δ6.78(2H), δ7.10(2H), δ7.52(2H), δ8. 86(2H). Prove that the obtained result is correct.

Claims (8)

1. A compound consisting of structural units of formula (I) with a molecular weight of 732.8-7328: Wherein, R is an oligopyridine compound of 2-5; n is an integer of 1-10. 2. The compound according to claim 1, characterized in that: said R is bipyridine or terpyridine; n is an integer of 1-10. 3. A method for producing the compound of claim 1, consisting essentially of the following steps: 1) 2-dimethylthiophene is reacted with liquid bromine in an ice bath in acetic acid to obtain 3,5-dibromo-2-methylthiophene; 2) 3,5-dibromo-2-methylthiophene was dissolved in anhydrous ether, injected into n-BuLi, and tributyl borate was added to obtain 2-methyl-3-bromo-5-boronic acid thiophene; 3) Dissolve bromobipyridine and Pd(PPh ₃ ) ₄ in tetrahydrofuran, and add 2-methyl-3-bromo-5-boronic acid thiophene with stirring to obtain 2-bipyridine-4-bromo-5-methyl Thiophene; 4) Low-temperature reaction of 2-bipyridine-4-bromo-5-methylthiophene with n-BuLi and perfluorocyclopentene to obtain the desired product. 4. The method according to claim 3, characterized in that: when the ratio of reactants is brominated bipyridine: 2-methyl-3-bromo-5-boronic acid thiophene: perfluorocyclopentene = 2:2 : 1, what is obtained is a bipyridine type diarylethene compound monomer. 5. The method according to claim 3, characterized in that: when the ratio of reactants is dibromobipyridine: 2-methyl-3-bromo-5-boronic acid thiophene: perfluorocyclopentene = 1: When it is 2:1, what is obtained is a chain polymer compound. 6. Use of the compound of claim 1 as an optical information storage material. 7. Use of the compound of claim 1 as a photochromic molecular device. 8. The use of the compound of claim 1 in the preparation of photochromic light-emitting devices.

Images