CN114031596A

CN114031596A - Bis-benzo-chromene photochromic compound and application thereof

Info

Publication number: CN114031596A
Application number: CN202111066139.2A
Authority: CN
Inventors: 范为正; 张鹤军; 王明华; 宋化灿; 朱国勋; 宋森川; 司云凤; 刘洋
Original assignee: Jiangsu Shike New Material Co ltd
Current assignee: Jiangsu Shike New Material Co ltd
Priority date: 2021-09-10
Filing date: 2021-09-10
Publication date: 2022-02-11
Anticipated expiration: 2041-09-10
Also published as: CN114031596B

Abstract

A dibenzochromene photochromic compound and an application thereof, wherein the structure of the compound is shown as a formula I:

wherein: r1, R2, R5 and R6 are respectively selected from hydrogen, methyl, methoxy, methylthio, aryl, halogen, CN and NO₂、CF₃Or CF₂H; r3, R4, R7 and R8 are respectively selected from hydrogen, methyl, methoxy, methylthio, halogen, CN and NO₂、CF₃Or CF₂H, and at least one of R3, R4, R7, R8 is an electron withdrawing group; l is selected from C1-C8 linear alkyl, branched alkyl, cyclic alkyl or substituent containing at least 1 heteroatom in the alkyl chain. The compound has high color development sensitivity, excellent durability and extremely short fading half-life. Can be used as memory material, light modulation material, photochromic lens material, optical filter material, display material, optical information device, optical switch element, photoresist material, light meter or decorative material.

Description

Bis-benzo-chromene photochromic compound and application thereof

Technical Field

The invention relates to the field of photochromic materials, in particular to a dibenzochromene photochromic compound and application thereof.

Background

Photochromism is a phenomenon of reversible action in which the color changes rapidly when some compounds are irradiated with light including ultraviolet rays, and returns to the original color when the irradiation is stopped and the compounds are left in the dark. The compound with the property is called as photochromic compound, and the photochromic material has wide application prospect in the fields of photochromic glasses, optical information storage, molecular switch, defense identification technology and the like, and is one of the research hotspots in the fields of chemistry and material science.

Naphthopyrans are known as photochromic compounds which are reported to be capable of changing color under the influence of multi-or monochromatic light, such as UV light. When the irradiation is stopped, or under the influence of temperature and/or of a poly-or monochromatic light different from the initial one, the compound returns to its initial color. Naphthopyrans find application in a variety of fields, for example in the manufacture of ophthalmic lenses, contact lenses, sunglasses, optical filters, optical cameras or other optical devices, as well as viewing devices, glazings and decorative objects. 2H-chromene has a neutral grey or brown colour in some cases after UV irradiation, which is of particular interest when used in color-changing lenses, since it does not require the use of dye mixtures of different colours to obtain the desired hue. In fact, dyes of different colors may have different UV aging resistance characteristics, different fading kinetics or different thermal dependencies, resulting in changes in the tint of the lens during use. For example, for ophthalmic lenses, rapid discoloration of photochromic articles in the absence of UV light is highly desirable for visual comfort and safety reasons (e.g., driving).

Disclosure of Invention

The present inventors have studied naphthopyran compounds and found that when an electron-withdrawing group is introduced into the benzene ring of 2H naphtho [1, 2-b ] pyran (chromene), the compounds have a short half-life of discoloration. And when the two benzo chromene compounds are connected through the electron donating groups, the fading half-life period can be obviously shortened, and the aging resistance can be improved. The compound has good development prospect.

In order to achieve the purpose, the invention comprises the following technical scheme:

a bis-benzo-chromene photochromic compound has a structure shown in formula (I):

wherein:

r1, R2, R5 and R6 are respectively selected from hydrogen, methyl, methoxy, methylthio, aryl, halogen, CN and NO₂、CF₃Or CF₂H；

R3, R4, R7 and R8 are respectively selected from hydrogen, methyl, methoxy, methylthio, halogen, CN and NO₂、 CF₃Or CF₂H, and at least one of R3, R4, R7, R8 is an electron withdrawing group;

l is selected from C1-C8 linear alkyl, branched alkyl, cyclic alkyl or substituent containing at least 1 heteroatom in the alkyl chain.

The bis-benzo chromene type light as described aboveA photochromic compound, preferably, said L is 1, 3-propylene, -C₂H₄OC₂H₄-, 1, 4-cyclohexyl or 1, 4-bicyclo [2.2.2]An octyl group.

The bis-benzo chromene photochromic compound is preferably characterized in that R3 and R7 are H, and R4 and R8 are F.

In another aspect, the present invention provides a photochromic composition comprising the bis-benzochromene photochromic compound described above.

In yet another aspect, the present invention provides a photochromic material comprising a bis-benzochromene photochromic compound as described above incorporated into an organic material, which is a polymeric, oligomeric, and/or monomeric material.

In yet another aspect, the present invention provides the use of the bis-benzochromene photochromic compounds described above as photochromic materials.

The bis-benzotrichlorides of the present invention can be incorporated into a variety of polymer matrices for ultimate use in the preparation of a variety of different articles. Typically, the polymer matrix in which the compound of formula I is incorporated or coated is colorless or slightly colored in its initial state, rapidly forming an intense color when exposed to UV light (365nm) or under daylight-type light sources. The polymer matrix returns to its original color once irradiation ceases. The compounds of formula I may be used alone or in combination with other photochromic materials. The use of two or more compounds of formula I to prepare an article is also contemplated.

Examples of polymers useful as photochromic materials in the present invention include, but are not limited to: alkyl, cycloalkyl, (poly or oligo) ethylene glycol, aryl or arylalkyl mono-, di-, tri-or tetraacrylates or mono-, di-, tri-or tetramethylacrylates, which may optionally be halogenated or comprise at least one ether and/or ester and/or carbonate and/or urethane and/or thiocarbamate and/or urea and/or amide group, polystyrene, polyether, polyester, polycarbonate (e.g. bisphenol-a polycarbonate, diallyl diethylene glycol polycarbonate), polyurethane, polyepoxide, polyurea, polyurethane, polythiourethane, polysiloxane, polyacrylonitrile, polyamide, aliphatic or aromatic polyester, vinyl (vinylic) polymer, cellulose acetate, cellulose triacetate, cellulose acetate propionate or polyvinyl butyral. Homopolymers and copolymers derived from the above materials may also be used.

As a method for dispersing the photochromic compound of the present invention in the above-mentioned polymeric solid matrix, a general method can be employed. Examples thereof include: and a method in which the above thermoplastic resin and the photochromic compound are kneaded in a molten state to disperse the photochromic compound in the resin. Alternatively, a method may be mentioned in which a photochromic compound is dissolved in the polymerizable monomer, and then a polymerization catalyst is added to polymerize the photochromic compound by heat or light, thereby dispersing the photochromic compound in the resin. Further, there are a method of dispersing a photochromic compound in the resin by dyeing the photochromic compound on the surface of the thermoplastic resin and the thermosetting resin.

The photochromic compound of the present invention can be used as a photochromic material in a wide range, and can be used as a memory material, a light control material, a photochromic lens material, an optical filter material, a display material, an optical information device, an optical switching element, a photoresist material, a light meter or a decorative material. The memory material may be a copying material, a printing photosensitive material, a memory material for a cathode ray tube, a laser photosensitive material, or a hologram photosensitive material.

The term "alkyl" used in the present invention means a straight or branched monovalent saturated hydrocarbon group having 1 to 8 carbon atoms, and examples thereof include, but are not limited to, methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-methyl-1-propyl, 2-butyl, 2-methyl-2-propyl, tert-butyl, 1-hexyl, 2-ethylbutyl and the like.

The term "cyclic alkyl" as used herein refers to cycloalkyl groups of 3 to 8 carbon atoms, but is not limited to cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, alkyl-substituted cycloalkyl groups.

The term "aryl" as employed herein by itself or as part of another substituent refers to a monovalent aromatic hydrocarbon radical derived from the removal of one hydrogen atom from a single carbon atom of a parent aromatic ring system. Aryl encompasses 5-and 6-membered carbocyclic aromatic rings, for example, benzene; bicyclic ring systems in which at least one ring is carbocyclic and aromatic, e.g., naphthalene, indane, and tetrahydronaphthalene; and tricyclic ring systems in which at least one ring is carbocyclic and aromatic, e.g., fluorene. Aryl encompasses polycyclic ring systems having at least one carbocyclic aromatic ring fused to at least one carbocyclic aromatic, cycloalkyl, or heterocycloalkyl ring.

The term "halogen" as used in the present invention means fluorine, chlorine or bromine.

Indicating that the substituent is attached thereto.

The compounds of formula I of the present invention can be prepared by the following method:

as shown in reaction formula 1, the method comprises the following steps:

(1) reacting the compound I-1 with ethinyl lithium to obtain a compound I-2;

(2) cyclizing the compound I-2 and the compound I-3 in the presence of camphoric acid to obtain a compound I-4;

(3) carrying out nucleophilic substitution on the compound I-4 and Br-L-Br under an alkaline condition to obtain a compound II-2;

(4) nucleophilic substitution is carried out on the compound II-2 and the compound I-8 under the alkaline condition to obtain a compound II-3.

The invention has the beneficial effects that: the compound of the general formula (I) has high color development sensitivity, excellent durability and extremely short fading half-life. There are various uses of the color-changing material, for example, a memory material, a light-adjusting material, a photochromic lens material, an optical filter material, a display material, an optical information device, an optical switching element, a photoresist material, a light quantity meter, a decorative material, or the like.

Detailed Description

The following examples illustrate but do not limit the synthesis of the compounds of formula (I). The temperatures are given in degrees Celsius. All evaporation was performed under reduced pressure if not otherwise stated. If not otherwise stated, the reagents were purchased from commercial suppliers and used without further purification. The structure of the final products, intermediates and starting materials is confirmed by standard analytical methods, such as elemental analysis, spectroscopic characterization, e.g., MS, NMR. Abbreviations used are those conventional in the art.

Preparation of an intermediate:

1. preparation of intermediate A-5: 10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ] chromen-5-ol

(1) A-3: preparation of 1, 1-bis (4-methoxyphenyl) prop-2-yn-1-ol

4, 4' -Dimethoxybenzophenone A-1(500mg, 2.06mmol) was dissolved in 10mL of ethylenediamine, and lithium acetylide ethylenediamine complex A-2(558mg, 6.20mmol) was added. The mixture was stirred at room temperature for 2 hours under a nitrogen atmosphere. After the reaction, the reaction mixture was quenched with ice water, and the reaction mixture was extracted with ethyl acetate. The organic layer was washed with water and saturated sodium chloride, and dried over anhydrous sodium sulfate. Concentration and purification of the crude product by silica gel column chromatography gave 1, 1-bis (4-methoxyphenyl) prop-2-yn-1-ol a-3(450mg, white solid) in yield: 81 percent. ESI-MS m/z: 269[ M + H]⁺。

(2) A-5: preparation of 10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ] chromen-5-ol

1, 1-bis (4-methoxyphenyl) propan-2-yn-1-ol A-3(450mg, 1.68mmol) was dissolved in toluene (10 mL), 8-fluoronaphthalene-1, 3-diol A-4(358mg, 2.01mmol) and camphorsulfonic acid (89mg, 0.5mmol) were added, followed by stirring at 60 ℃ for 2 hours, after completion of the reaction, concentration and purification of the crude product by silica gel column chromatography to give 10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ] (product of the reaction)]Chromen-5-ol a-5(200mg, white solid), yield: 28 percent. ESI-MS m/z：429[M+H]⁺。

2. Preparation of intermediate A-7: 10-trifluoromethyl-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ] chromen-5-ol

1, 1-bis (4-methoxyphenyl) propan-2-yn-1-ol A-3(450mg, 1.68mmol) was dissolved in toluene (10 mL), 8-trifluoromethylnaphthalene-1, 3-diol A-6(458mg, 2.01mmol) and camphorsulfonic acid (89mg, 0.5mmol) were added, followed by stirring at 60 ℃ for 2 hours, after completion of the reaction, concentration and purification of the crude product by silica gel column chromatography to give 10-trifluoromethyl-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ] (S-H)]Chromen-5-ol a-7(180mg, white solid), yield: 22 percent. ESI-MS m/z: 479[ M + H ]]⁺。

Example 1: preparation of 1, 3-bis ((10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ] chromen-5-yl) oxy) propane

Reacting 10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H]Chromen-5-ol A-5(500mg, 1.17mmol) was dissolved in acetonitrile (5mL), potassium carbonate (194mg, 1.4mmol) was added, and the mixture was stirred at room temperature for 0.5h, followed by addition of 1, 3-dibromopropane (2.36g, 11.7mmol) and stirring at room temperature for 16 h. After the reaction, 20mL of water was added, extraction was performed with ethyl acetate, the organic phase was washed with saturated sodium chloride, dried over anhydrous sodium sulfate, concentrated, and the crude product was purified by silica gel column chromatography to give 5- (3-bromopropoxy) -10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ]]Chromene a-15(400mg, white solid), yield: 62 percent. ESI-MS m/z: 549, 551[ M + H ]]⁺。

Reacting 10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H]Chromen-5-ol A-5(154mg, 0.36mmol) was dissolved in acetonitrile (5mL), potassium carbonate (50mg, 0.36mmol) was added, stirring at room temperature for 0.5H, then 5- (3-bromopropoxy) -10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ] (R)]Chromene A-15(200mg, 0.36 mmo)l), stirred at room temperature for 16 hours. After the reaction, 10mL of water was added, extraction was performed with ethyl acetate, the organic phase was washed with saturated sodium chloride, dried over anhydrous sodium sulfate, concentrated, and the crude product was purified by silica gel column chromatography to give 1, 3-bis ((10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ]]Chromen-5-yl) oxy) propane (45mg, white solid), yield: 14 percent. ESI-MS m/z: 897[ M + H]⁺。

¹H-NMR(400MHz，DMSO-d₆)：δ7.82-7.61(m，2H)，7.46-7.33(m，10H)， 7.32-7.16(m，2H)，6.87-6.75(m，10H)，6.61(d，J＝7.2Hz，2H)，6.38(d，J＝7.2Hz，2H)， 4.32(t，J＝8.2Hz，4H)，3.52(s，12H)，2.21-2.19(m，2H).

Example 2: preparation of 1, 3-bis ((10-trifluoromethane-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ] chromen-5-yl) oxy) propane

Reacting 10-trifluoromethyl-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H]Chromen-5-ol A-7(500mg, 1.05 mmol) was dissolved in acetonitrile (5mL), potassium carbonate (173mg, 1.25mmol) was added, and the mixture was stirred at room temperature for 0.5h, followed by addition of 1, 3-dibromopropane (2.12g, 10.5mmol) and stirring at room temperature for 16 h. After the reaction, 20mL of water was added, extraction was performed with ethyl acetate, the organic phase was washed with saturated sodium chloride, dried over anhydrous sodium sulfate, concentrated, and the crude product was purified by silica gel column chromatography to give 5- (3-bromopropoxy) -10-trifluoromethyl-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ]]Chromene a-16(300mg, white solid), yield: 48 percent. ESI-MS m/z: 599, 601[ M + H]⁺。

Reacting 10-trifluoromethyl-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H]Chromen-5-ol A-7(100mg, 0.21mmol) was dissolved in acetonitrile (5mL), potassium carbonate (28mg, 0.21mmol) was added, stirring at room temperature for 0.5H, then 5- (3-bromopropoxy) -10-trifluoromethyl-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ]]Chromene A-16 (126mg, 0.21mmol) was stirred at room temperature for 16 h. After the reaction is finished, 10mL of water is added, ethyl acetate is used for extraction, an organic phase is washed by saturated sodium chloride,dried over anhydrous sodium sulfate, concentrated, and the crude product was purified by silica gel column chromatography to give 1, 3-bis ((10-trifluoromethyl-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ]]Chromen-5-yl) oxy) propane (35mg, white solid), yield: 19 percent. ESI-MS m/z: 997[ M + H ]]⁺。

¹H-NMR(400MHz，DMSO-d₆)：δ8.13-7.65(m，2H)，7.55-7.37(m，10H)， 7.32-7.12(m，2H)，6.88-6.73(m，10H)，6.62(d，J＝7.2Hz，2H)，6.38(d，J＝7.2Hz，2H)， 4.33(t，J＝8.2Hz，4H)，3.52(s，12H)，2.23-2.19(m，2H).

Example 3: 2, 2' -bis ((10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ] chromen-5-yl) oxy) dioxydiethyl ether

Reacting 10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H]Chromen-5-ol A-5(500mg, 1.17mmol) was dissolved in acetonitrile (5mL), potassium carbonate (194mg, 1.4mmol) was added, and the mixture was stirred at room temperature for 0.5h, followed by addition of 2, 2' -dibromodiethyl ether (2.71g, 11.7mmol), and stirring at room temperature for 16 h. After the reaction, 20mL of water was added, extraction was performed with ethyl acetate, the organic phase was washed with saturated sodium chloride, dried over anhydrous sodium sulfate, concentrated, and the crude product was purified by silica gel column chromatography to give 5- (2- (2-bromoethoxy) ethoxy) -10-fluoro-2, 2-bis (4-methoxyphenyl) -2 hbenzo [ H ]]Chromene a-17(300mg, white solid), yield: 44 percent. ESI-MS m/z: 579, 581[ M + H [ ]]⁺。

Reacting 10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H]Chromen-5-ol A-5(154mg, 0.36mmol) was dissolved in acetonitrile (5mL), potassium carbonate (50mg, 0.36mmol) was added, stirring was carried out at room temperature for 0.5H, then 5- (2- (2-bromoethoxy) ethoxy) -10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ], (N-ethyl-L-methyl-ethyl-N-methyl-phenyl)]Chromene A-17 (208mg, 0.36mmol) was stirred at room temperature for 16 h. After the reaction, 10mL of water was added, extraction was performed with ethyl acetate, the organic phase was washed with saturated sodium chloride, dried over anhydrous sodium sulfate, concentrated, and the crude product was purified by silica gel column chromatography to obtain 2, 2' -bis ((10-fluoro-2, 2-bis (4-methoxy-2-methoxy-4-fluoro-4-methoxy-4-yl) etherPhenyl) -2H-benzo [ H]Chromen-5-yl) oxy) dioxydiethyl ether (32mg, white solid), yield: 10 percent. ESI-MS m/z: 927[ M + H]⁺。

¹H-NMR(400MHz，DMSO-d₆)：δ7.81-7.61(m，2H)，7.46-7.33(m，10H)， 7.32-7.16(m，2H)，6.87-6.75(m，10H)，6.62(d，J＝7.2Hz，2H)，6.37(d，J＝7.2Hz，2H)，4.42(t，J＝8.0Hz，4H)，3.77(t，J＝8.0Hz，4H)，3.51(s，12H).

Example 4: 1, 4-bis (10-fluoro-5- ((4- ((10-fluoro-2, 2-bis (4-methoxyphenyl) -2 hbenzo [ H ] chromen-5-yl) oxy) cyclohexyl) oxy)

Reacting 10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H]Chromen-5-ol A-5(500mg, 1.17mmol) was dissolved in acetonitrile (5mL), potassium carbonate (194mg, 1.4mmol) was added, and the mixture was stirred at room temperature for 0.5h, followed by addition of 1, 4-dibromocyclohexane (2.83g, 11.7mmol) and stirring at room temperature for 16 h. After the reaction is finished, 20mL of water is added, ethyl acetate is used for extraction, an organic phase is washed by saturated sodium chloride, dried by anhydrous sodium sulfate and concentrated, and a crude product is purified by silica gel column chromatography to obtain 5- ((4-bromocyclohexyl) oxy) -10-fluoro-2, 2-bis (4-methoxyphenyl) -2H benzo [ H ]]Chromene a-18(300mg, white solid), yield: 44 percent. ESI-MS m/z: 589, 591 [ M + H]⁺。

Reacting 10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H]Chromen-5-ol A-5(154mg, 0.36mmol) was dissolved in acetonitrile (5mL), potassium carbonate (50mg, 0.36mmol) was added, stirring was carried out at room temperature for 0.5H, then 5- ((4-bromocyclohexyl) oxy) -10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H ] was added]Chromene A-18 (212mg, 0.36mmol) was stirred at room temperature for 16 h. After the reaction is finished, 10mL of water is added, ethyl acetate is used for extraction, an organic phase is washed by saturated sodium chloride, anhydrous sodium sulfate is dried, the organic phase is concentrated, a crude product is purified by silica gel column chromatography, and 1, 4-bis (10-fluoro-5- ((4- ((10-fluoro-2, 2-bis (4-methoxyphenyl) -2H benzo [ H)]Chromen-5-yl) oxy) cyclohexyl) oxy) (55mg, white solid), yield: 17 percent.ESI-MS m/z：937 [M+H]⁺。

¹H-NMR(400MHz，DMSO-d₆)：δ7.84-7.60(m，2H)，7.46-7.32(m，10H)，7.33-7.16(m，2H)，6.88-6.75(m，10H)，6.61(d，J＝7.2Hz，2H)，6.38(d，J＝7.2Hz，2H)，3.64-3.55(m，2H)，3.52(s，12H)，1.92-1.83(m，8H).

Example 5: 1, 4-bis (10-fluoro-5- ((4- ((10-fluoro-2, 2-bis (4-methoxyphenyl) -2 hbenzo [ H ] chromen-5-yl) oxy) bicyclo [2.2.2] octane) oxy)

Reacting 10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H]Chromen-5-ol A-5(500mg, 1.17mmol) was dissolved in acetonitrile (5mL), potassium carbonate (194mg, 1.4mmol) was added, stirring was carried out at room temperature for 0.5h, and then 1, 4-dibromobicyclo [2.2.2] was added]Octane (3.32g, 11.7mmol) was stirred at room temperature for 16 hours. After the reaction is finished, 20mL of water is added, ethyl acetate is used for extraction, an organic phase is washed by saturated sodium chloride, dried by anhydrous sodium sulfate and concentrated, and a crude product is purified by silica gel column chromatography to obtain 5- ((4-bromobicyclo [ 2.2.2)]Octane-1-yl) oxy) -10-fluoro-2, 2-bis (4-methoxyphenyl) -2 hbenzo [ H]Chromene a-19(200mg, white solid), yield: 28 percent. ESI-MS m/z: 615, 617[ M + H ]]⁺。

Reacting 10-fluoro-2, 2-bis (4-methoxyphenyl) -2H-benzo [ H]Chromen-5-ol A-5(154mg, 0.36mmol) was dissolved in acetonitrile (5mL), potassium carbonate (50mg, 0.36mmol) was added, stirring was carried out at room temperature for 0.5h, then 5- ((4-bromobicyclo [2.2.2] was added]Octane-1-yl) oxy) -10-fluoro-2, 2-bis (4-methoxyphenyl) -2 hbenzo [ H]Chromene A-19(221mg, 0.36mmol) was stirred at room temperature for 16 hours. After the reaction is finished, 10mL of water is added, ethyl acetate is used for extraction, an organic phase is washed by saturated sodium chloride, anhydrous sodium sulfate is dried, the organic phase is concentrated, a crude product is purified by silica gel column chromatography, and 1, 4-bis (10-fluoro-5- ((4- ((10-fluoro-2, 2-bis (4-methoxyphenyl) -2H benzo [ H)]Chromen-5-yl) oxy) bicyclo [2.2.2]Octane) oxy) (36mg, white solid), yield: 10 percent. ESI-MS m/z: 963[ M + H ]]⁺。

¹H-NMR(400MHz，DMSO-d₆)：δ7.85-7.60(m，2H)，7.46-7.31(m，10H)， 7.33-7.16(m，2H)，6.88-6.74(m，10H)，6.62(d，J＝7.2Hz，2H)，6.37(d，J＝7.2Hz，2H)， 3.51(s，12H)，1.88-1.23(m，12H).

Example 6: preparation of photochromic materials

A photochromic curable composition was prepared by thoroughly mixing 0.04 parts by mass of the chromene compound obtained in each of examples 1 to 5, 13 parts by mass of tetraethylene glycol dimethacrylate, 48 parts by mass of 2, 2-bis [4- (methacryloyloxyethoxy) phenyl ] propane, 2 parts by mass of polyethylene glycol monoallyl ether, 20 parts by mass of trimethylolpropane trimethacrylate, 9 parts by mass of glycidyl methacrylate, 6 parts by mass of alpha-methylstyrene, 2 parts by mass of a-methylstyrene dimer, and 1 part by mass of t-butylperoxy 2-ethylhexanoate as a polymerization initiator. Next, the obtained photochromic curable composition was injected into a mold comprising a glass plate and a gasket (gasket) made of an ethylene-vinyl acetate copolymer, and cast polymerization was performed. The polymerization process is as follows: the temperature was slowly raised from 30 ℃ to 90 ℃ over 18 hours using an air oven and held at 90 ℃ for 2 hours. After the polymerization was completed, the polymer was taken out of the glass mold of the mold to obtain photochromic material samples prepared from the compounds of examples 1 to 5.

Experimental example 1: evaluation of photochromic Properties in solution

Evaluation of a photochromic cured product (photochromic optical article) was carried out by the In mass method. Photochromic properties and half-life of discoloration were evaluated except that each of the polymers obtained in example 6 (photochromic cured product (optical product) having a thickness of 2 mm) was used as a sample and the light irradiation time was set to 1 second. The results are shown in Table 1.

Maximum absorption wavelength (Amax): the maximum absorption wavelength after color development, which was obtained by a spectrophotometer (instant multichannel photodetector MCPD2000M) manufactured by gaku (ltd.) electronic industry, is an index of the color tone at the time of color development.

Color development concentration (ABS): the absorbance of the sample after 0.5 second of light irradiation at the maximum absorption wavelength is an index of the color density. It can be said that the higher the value, the larger the change in coloration by light irradiation, the better the photochromic property.

Fading half-life (T1/2): the time required for the absorbance at the maximum absorption wavelength of the sample to decrease to a half value when the light irradiation is stopped is an index of the fading speed. The shorter this time, the faster the fading speed.

Yellowness (YI): in order to evaluate the yellowing factor after polymerization and curing, the color difference of the sample after polymerization and curing was measured by using a color difference meter (SM-4) manufactured by a testing machine (Ltd.). The smaller the value of YI, the higher the transparency of the polymerized cured body (including the cured film), or the smaller the degree of deterioration of the evaluation compound.

Survival Rate (A)₅₀/A₀X100): in order to evaluate the durability of color development by light irradiation, the following deterioration acceleration test was performed. The obtained polymer (sample) was accelerated to deteriorate for 50 hours by xenon arc weather resistance X25 manufactured by testing machine (Ltd.). Thereafter, the above-mentioned color development concentration was evaluated before and after the test, and the color development concentration before the test was measured (A)₀) And the color development concentration after the test (A)₅₀) The ratio of them (A)₅₀/A₀) The residual ratio is set as an index of the durability of the color development. The higher the residual ratio, the higher the durability of color development.

Table 1:

comparative example 1

For further comparison, the same procedures as in example 6 were used to prepare photochromic cured films using the following compounds, and the characteristics of the resultant photochromic plastic lenses were evaluated by the procedure of Experimental example 1, and the results thereof are shown in Table 2:

TABLE 2

Experimental results show that the bis-benzo chromene compound introduces an electron-withdrawing group on a benzene ring and simultaneously connects differently substituted benzo chromenes through an electron-donating group, so that the bis-benzo chromene compound has practical fading half-life and good aging resistance, and has photochromism of which the color disappears instantly once light irradiation is stopped.

Therefore, when a photochromic material such as a photochromic lens is produced using the bis-chromene compound of the present invention, a photochromic lens having such a property that it develops color rapidly when coming outdoors, fades rapidly and returns to the original color tone when going from outdoors to indoors, and can be used for a long period of time can be produced.

The bis-benzochromene compound of the present invention exhibits the above excellent effects, and is therefore suitable for various applications, for example, memory materials, light control materials, photochromic lens materials, optical filter materials, display materials, optical information devices, optical switching elements, photoresist materials, photometers, and decorative materials.

Claims

1. A bis-benzo chromene photochromic compound is characterized in that the structure of the compound is shown as the formula (I):

wherein:

R3, R4, R7 and R8 are respectively selected from hydrogen, methyl and methylOxy, methylthio, halogen, CN, NO₂、CF₃Or CF₂H, and at least one of R3, R4, R7, R8 is an electron withdrawing group;

2. The bis-benzo chromene photochromic compound of claim 1, wherein L is 1, 3-propylene, -C₂H₄OC₂H₄-, 1, 4-cyclohexyl or 1, 4-bicyclo [2.2.2]An octyl group.

3. The bis-benzo chromene photochromic compound of claim 1 or claim 2, wherein R3 and R7 are each H and R4 and R8 are each F.

4. A photochromic composition comprising the bis-benzo chromene photochromic compound according to any one of claims 1 to 3.

5. Photochromic material, characterized in that it comprises a bis-benzo-chromene-based photochromic compound according to any one of claims 1 to 3 incorporated into an organic material, which is a polymeric, oligomeric and/or monomeric material.

6. Use of the bis-benzo chromene photochromic compound according to any one of claims 1 to 3 as a photochromic material.

7. Use according to claim 6, wherein the photochromic material is a memory material, a dimming material, a photochromic lens material, an optical filter material, a display material, an optical information device, an optical switching element, a photoresist material, a light gauge or a decorative material.

8. The use according to claim 7, wherein the memory material is a copying material, a printing photosensitive material, a memory material for a cathode ray tube, a laser photosensitive material or a hologram photosensitive material.