JP2003342266A - Bisbenzoxazole compound - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a compound having excellent solubility and light fastness and expected to be useful as a fluorescent brightener, a wavelength converting material or an ultraviolet shielding material. <P>SOLUTION: A bisbenzoxazole compound is expressed by formula (1) (Ar is a substituted or unsubstituted p-phenylene, or the like; R<SP>1</SP>and R<SP>2</SP>are each H or a substituted or unsubstituted alkyl; and (m) and (n) are each an integer of ≥2). <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a bisbenzoxazole compound. More specifically, the present invention relates to a bisbenzoxazole compound useful as a synthetic intermediate, and a bisbenzoxazole compound useful as a fluorescent whitening material, a light wavelength conversion material, or an ultraviolet blocking material.

[0002]

2. Description of the Related Art Fluorescent whitening is the process of compensating for the pale yellowish intrinsic color of fibers, polymers or other organic substances with blue fluorescence to give a pure white appearance. It is called whitening agent (or material).
Typical optical brighteners added to polymers are 2,5
-Bis [5-t-butylbenzoxazol-2-yl] thiophene (such as U.S. Pat. No. 3,449,257) and bis (benzoxazolyl) stilbene derivatives and mixtures thereof (Japanese Patent Publication No. 41-20225).
Publication, European Patent Publication EP No. 684,278A,
JP-A-8-231808) and the like, which are widely used. However, since these optical brighteners have insufficient light fastness or insufficient solubility, it is desired to develop new materials that improve these drawbacks.

In recent years, the importance of environmental problems and energy problems has become more and more important, and the effective use of solar energy has become extremely important. As one of them, let's promote the growth of greenhouse-cultivated plants by including a fluorescent brightening agent in vinyl chloride resin films for greenhouses, etc., and converting the ultraviolet part of sunlight of 380 nm or less that is not used for plant growth into visible light. (Japanese Patent Laid-Open No. 14461/1992)
No. 8). However, the conventional fluorescent whitening agents have problems of insufficient light fastness and low solubility in an organic solvent necessary for coating a film. Therefore, it is desired to develop a fluorescent whitening agent having excellent light fastness and solubility that is used for this purpose.

In addition to the above, it has been proposed to use a fluorescent whitening agent as a light wavelength conversion material, for example, in a light emitting screen resin (Japanese Patent Laid-Open No. 4-93388). However, even in this application, development of a fluorescent whitening agent having improved light fastness and film processability is desired.

In recent years, the damage caused by insects flying at night on window glasses of hospitals and factories has become a serious hygiene problem.
Especially in convenience stores and restaurants that handle large amounts of food, many accidents due to flying insects occur every year. In general, insects have a specific directional motion characteristic with respect to light and have a property of being directed to a light source (called traveling property). It is said that most insects have a central sensitivity to ultraviolet rays having a wavelength of 360 nm, and have a strong running property with respect to light in the visible ray range of ultraviolet rays to a short wavelength (up to about 420 nm) (hereinafter referred to as insect attracting light). (Reference: Sadahiko Konno, Pharm.Tec
h. Japan, 14, 653 (1998)).

Therefore, in food factories and the like, there is a case in which a window is covered with an insect repellent film or a fluorescent lamp is covered with an insect repellent plastic cover so as not to let out the insect attracting light emitted from the fluorescent lamp. However, insect-repellent films and the like that cut off light exceeding 400 nm, which is a human visible light region, are colored yellow, so that there is a drawback that the external appearance of a convenience store becomes poor. Therefore, a method utilizing the principle of a fluorescent whitening agent has been considered as a method of cutting off insect visible light but preventing human eyes from feeling yellowish color (Japanese Patent Laid-Open No. 2002-53824). The optical brightener is a material that emits fluorescence as described above and does not make the human eye feel yellow. Absorbs light around 400 nm, 4
If blue fluorescence having an absorption maximum at a wavelength longer than 20 nm is emitted, the yellow body can be reduced without reducing the insect repellent effect.

In order to use a fluorescent whitening agent for this purpose, it is preferable that the fluorescent whitening agent is as excellent as possible in light fastness and has solubility in an organic solvent capable of forming a thin film or has film processability. . Therefore, it is desired to develop a fluorescent whitening agent having these properties improved.

[0008]

Therefore, the present inventors have found that a compound having a benzoazole skeleton, which has an excellent feature of emitting strong fluorescence, has high light fastness and solubility in an organic solvent or processability into a film. The research was carried out for the purpose of finding an improved molecular structure and finding a synthetic intermediate of the compound.

[0009]

As a result, they have found that a group of bisbenzoxazole compounds capable of deriving a certain bisbenzoxazole compound as a synthetic intermediate has a molecular structure capable of achieving this object. That is, the object of the present invention has been achieved by a bisbenzoxazole compound represented by the general formula (I), which is a synthetic intermediate, and a bisbenzoxazole compound represented by the general formula (II), which is derivable therefrom.

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

[0011]

[Chemical 3]

In the general formula (I), Ar is a substituted or unsubstituted p-phenylene group, 1,4-naphthylene group, 1,5.
-Naphthylene group, 4,4'-biphenylene group, 4,
It represents a 4 ″ -p-terphenylene group, a 4,4 ″ ′-p-quataphenylene group or a 2,5-thiophenediyl group. R ¹ and R ² each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group. m and n each independently represent an integer of 2 or more.

The present invention also provides a bisbenzoxazole compound represented by the general formula (II).

[0014]

[Chemical 4]

In the general formula (II), Ar is a substituted or unsubstituted p-phenylene group, 1,4-naphthylene group, 1,5
-Naphthylene group, 4,4'-biphenylene group, 4,
It represents a 4 ″ -p-terphenylene group, a 4,4 ″ ′-p-quataphenylene group or a 2,5-thiophenediyl group. R ¹ and R ² each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group. R ³ and R ⁴ each independently represent a substituted or unsubstituted alkyl group, aryl group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylaminocarbonyl group or arylaminocarbonyl group. m and n each independently represent an integer of 2 or more.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The compounds represented by formulas (I) and (II) of the present invention will be described in detail below. In addition, in this specification, "-" is used by the meaning including the numerical value described before and after that as a lower limit and an upper limit.

Ar in the general formulas (I) and (II)
Is a substituted or unsubstituted p-phenylene group, 1,4-
Naphthylene group, 1,5-naphthylene group, 4,4′-biphenylene group, 4,4 ″ -p-terphenylene group, 4,
It represents a 4 '''-p-quataphenylene group or a 2,5-thiophenediyl group. Preferably, an unsubstituted p-phenylene group, 1,4-naphthylene group, 1,5-naphthylene group,
4,4′-biphenylene group, 4,4 ″ -p-terphenylene group, 4,4 ′ ″-p-quataphenylene group or 2,5-thiophenediyl group, and particularly preferably an unsubstituted group It is a p-phenylene group, a 1,4-naphthylene group or a 2,5-thiophenediyl group.

When Ar has a substituent, the substituent is preferably a halogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, a dialkylamino group, an N-alkyl-N-arylamino group, or a diaryl. An amino group, more specifically, a hydrogen atom, a fluorine atom, a halogen atom which is a chlorine atom or a bromine atom, a substituted or unsubstituted straight-chain, branched or cyclic alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted Substituted aryl group having 6 to 20 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, substituted or unsubstituted aryloxy group having 6 to 20 carbon atoms, substituted or unsubstituted 2 to 16 carbon atoms A dialkylamino group, a substituted or unsubstituted N-alkyl-N-arylamino group having 7 to 21 carbon atoms, Carbon atoms other substituted or unsubstituted 1
2 to 36 diarylamino groups. Adjacent groups of these groups may combine with each other to form a saturated ring or an unsaturated ring (such as an aromatic ring). Further, the alkyl groups of the dialkylamino group, the alkyl groups of the N-alkyl-N-arylamino group and the aryl groups, and the aryl groups of the diarylamino group are directly or indirectly bonded to each other to form a saturated or unsaturated nitrogen-containing group. It may form a saturated ring.

Specific substituents other than hydrogen atom and halogen atom include methyl group, ethyl group, n-propyl group,
n-octyl group, n-dodecyl group, 2-methoxyethyl group, 2-phenylmethyl group, benzyl group, isopropyl group, isobutyl group, s-butyl group, tert-butyl group, tert-amyl group, tert-octyl group , An alkyl group such as a cyclopentyl group, a cyclohexyl group, or a cycloheptyl group; a phenyl group, a 2-, 3- or 4-methylphenyl group, a 4-t-butylphenyl group, a 4-methoxyphenyl group, a 4-dimethylaminophenyl group. Group, 1- or 2-naphthyl group, anthryl group,
Or an aryl group such as a phenanthryl group; a methoxy group, an ethoxy group, an n-propoxy group, an n-butoxy group,
Alkoxy group such as n-hexyloxy group, isopropoxy group, isobutoxy group, tert-butoxy group, cyclopentyloxy group or cyclohexyloxy group; phenoxy group, 2-, 3- or 4-methylphenoxy group, 4-tert- Butylphenoxy group, 4-phenylphenoxy group, 4-methoxyphenoxy group, 2-
Aryloxy groups such as cyclohexylphenoxy group, 3-ethylphenoxy group, 1- or 2-naphthoxy group, anthryloxy group, or phenanthryloxy group; dimethylamino group, diethylamino group, dibutylamino group, dioctylamino group, N-methylbutylamino group, bis (2-methoxyethyl) amino group, bis (2-chloroethyl) amino group, 1-pyrrolidyl group, 1
-Dialkylamino group such as piperidyl group or 1-morphonyl group; N-methylanilino group, N-butylanilino group, N-methyl-1-naphthylamino group or 1
-N-alkyl-N-arylamino group such as indolenyl group; or diphenylamino group, N- (3-methylphenyl) anilino group, N- (4-methylphenyl) anilino group, bis (4-methylphenyl) amino Group, N-
Examples thereof include diarylamino groups such as naphthylanilino group, dinaphthylamino group, 5-carbazolyl group and 9H-tribenz [b, d, f] azepin-1-yl group.

The preferred Ar substituent is an alkyl group, an aryl group, an alkoxy group or a diarylamino group. More preferably, it is an alkyl group.

R ¹ and R ² in formulas (I) and (II) each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group, preferably a hydrogen atom or a substituted group having 1 to 8 carbon atoms. Alternatively, it represents an unsubstituted alkyl group.
More specifically, the alkyl group includes a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and a tert group.
An alkyl group such as -butyl group, 1,1-dimethylpropyl (tert-amyl) group, 1,1-dimethyl-3,3-dimethylbutyl group, 2-ethylhexyl group, cyclopentyl group or cyclohexyl group. When these groups have a substituent, the substituent is a halogen atom, an aryl group, an alkoxy group, an acyloxy group, a hydroxyl group or the like. Specific examples of the halogen atom, the aryl group and the alkoxy group include those exemplified as the substituent of Ar. Further, the acyloxy group is preferably a group having 2 to 40 carbon atoms, and specific examples thereof include an acetoxy group, a benzoyloxy group, a pivaloyloxy group,
2-ethylhexanoyloxy group, 2- (2,4-di-
Examples thereof include a tert-amylphenoxy) butanoyloxy group and a 4- (p-methoxyphenoxy) butyryloxy group.

R ¹ and R ² preferably have 1 to 8 carbon atoms.
Is an unsubstituted alkyl group, particularly preferably a branched or cyclic C 4-8 unsubstituted alkyl group (for example, a tert-butyl group, a cyclohexyl group).

R ³ and R ⁴ in the general formula (II) are each independently a substituted or unsubstituted alkyl group, aryl group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylaminocarbonyl group or arylamino group. Represents a carbonyl group, preferably a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and 6 carbon atoms
~ 30 substituted or unsubstituted aryl group, having 2 to 2 carbon atoms
40 substituted or unsubstituted acyl groups, 2 to 20 carbon atoms
Substituted or unsubstituted alkoxycarbonyl group, substituted or unsubstituted aryloxycarbonyl group having 7 to 40 carbon atoms, substituted or unsubstituted alkylaminocarbonyl group having 2 to 20 carbon atoms, or substituted having 7 to 40 carbon atoms Alternatively, it represents an unsubstituted arylaminocarbonyl group.

Specific examples of R ³ and R ⁴ include methyl group, ethyl group, n-propyl group, 2-methoxyethyl group, 2-phenylmethylbenzyl group, isopropyl group,
Alkyl group such as isobutyl group, s-butyl group, tert-butyl group, cyclohexyl group or p-methoxybenzyl group; phenyl group, 2-, 3- or 4-methylphenyl group, 4-tert-butylphenyl group, 4 −
Methoxyphenyl group, 4-dimethylaminophenyl group,
1- or 2-naphthyl group, anthryl group, phenanthryl group or 2,5-di-tert-butyl-4-
Aryl group such as methoxyphenyl group; acetyl group, pivaloyl group, 2-ethylhexanoyl group, 2- (2,4
-Di-tert-amylphenoxy) butanoyl group, benzoyl group, 4-tert-butylbenzoyl group, 2-
Acetyl group such as naphthoyl group, 2- (p-methoxyphenoxy) isovaleryl group, or 4- (p-methoxyphenoxy) butyryl group; methoxycarbonyl group, ethoxycarbonyl group, isopropoxycarbonyl group, te
rt-butoxycarbonyl group, cyclohexyloxycarbonyl group, or 3- (p-methoxyphenoxy)
Alkoxycarbonyl group such as propyloxycarbonyl group; phenoxycarbonyl group, 2-, 3- or 4
-Methylphenoxycarbonyl group, 4-tert-butylphenoxycarbonyl group, 4-phenylphenoxycarbonyl group, 4-methoxyphenoxycarbonyl group, 1
Or an aryloxycarbonyl group such as 2-naphthoxycarbonyl group, anthryloxycarbonyl group or phenanthryloxycarbonyl; methylaminocarbonyl group, hexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dimethyl Aminocarbonyl group, N-methylbutylamino group, 1-pyrrolidylcarbonyl group or 1-
Examples thereof include an alkylaminocarbonyl group such as a morphonylcarbonyl group; and an arylaminocarbonyl group such as a phenylcarbamoyl group, a 4-tert-butylphenylcarbamoyl group or a 2-naphthylaminocarbonyl group.

Preferably, R ³ and R ⁴ have ^{3 to} 2 carbon atoms.
0-substituted or unsubstituted alkyl group, having 9 to 30 carbon atoms
Or a substituted or unsubstituted aryl group having 4 to 40 carbon atoms, a substituted or unsubstituted acyl group having 4 to 40 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 4 to 20 carbon atoms, or a substituted or unsubstituted group having 11 to 40 carbon atoms It represents an aryloxycarbonyl group, and particularly preferably a substituted or unsubstituted acyl group having 4 to 40 carbon atoms, or a substituted or unsubstituted alkoxycarbonyl group having 4 to 20 carbon atoms.

C _m H in the general formulas (I) and (II)
_2m, C _n H _2n may be linear or branched, these m and n represents an integer of 2 or more independently preferably 2
Is an integer of 8 to 8 and particularly preferably an integer of 4 to 6.

As a group of compounds represented by the general formula (I),
For example, there may be mentioned a compound group in which R ¹ and R ² are the same, a compound group in which m and n are the same, and a compound group in which R ¹ and R ² are the same and m and n are also the same. In addition, the general formula (I
As the compound group represented by I), for example, a compound group in which R ¹ and R ² are the same, a compound group in which R ³ and R ⁴ are the same, a compound group in which m and n are the same, R ¹ and R ² Are the same and R ³
And R ⁴ are the same, and m and n are also the same. The general formula (II) may be a constituent element of a polymer or a copolymer, in which case R ³ and / or R ⁴ serves as a binding site of the polymer chain. The polymer and copolymer are preferably polycarbonate or polyester.

Further, the compound represented by the general formula (II) is
As in the following polymer, the structural unit represented by the general formula (II) may have a polymerized structure.

[0029]

[Chemical 5] In the above formula, p is preferably 2 to 1000, and 10 to 5
00 is more preferable.

Specific examples of the compounds represented by formulas (I) and (II) of the present invention are shown below, but the compounds included in the present invention are not limited to these.

[0031]

[Chemical 6]

[0032]

[Chemical 7]

[0033]

[Chemical 8]

[0034]

[Chemical 9]

[0035]

[Chemical 10]

[0036]

[Chemical 11]

[0037]

[Chemical 12]

Representative synthetic routes for the compounds of the present invention represented by the general formulas (I) and (II) are shown below. By passing through the compound represented by the general formula (I),
Various compounds represented by I) can be easily produced.

[0039]

[Chemical 13]

(In the formula, Ar, R ¹ , R ² , R ³ , R ⁴ , m and n represent the same groups or numbers as described above. X represents Cl or B.
represents r or I. R'is a protecting group (eg benzyl group)
Represents )

As shown in the synthetic route, the compound represented by the general formula (I) which is a useful synthetic intermediate is a compound of the general formula (A) which can be synthesized using resorcin as a starting material. No. 56-100771), the compound represented by the general formula (B) is alkylated to the compound represented by the general formula (C), and then acid-hydrolyzed to form the compound represented by the general formula (D). The compound represented by The obtained compound represented by the general formula (D) is reacted with the acid chloride represented by the general formula (E) to give a compound represented by the general formula (F), and the compound represented by the general formula (G ) Is obtained, and the compound is synthesized by the debenzylation reaction. The compound represented by the general formula (G) is often a compound included in the general formula (II).

The key reaction is the conversion of the compound represented by the general formula (D) into the compound represented by the general formula (G), which is represented by the compound represented by the general formula (D) and the general formula (E). The induction of the compound represented by the general formula (F) by the reaction of the compound can be quantitatively carried out without using a base, usually by mixing in an amide solvent. The dehydration reaction from the obtained compound represented by the general formula (F) to the compound represented by the general formula (F) is usually a high boiling point solvent (eg, toluene, xylene, mesitylene, chlorobenzene, dichlorobenzene or nitrobenzene). It can be carried out by adding a catalyst-free or acid catalyst (for example, p-toluenesulfonic acid) and heating (preferably 100 to 200 ° C.).

The compound represented by the general formula (I) can be easily induced to the compound represented by the general formula (II) by a general method of deriving from an alcohol.

The compound of the present invention can be purified by silica gel column chromatography and recrystallization method, and if necessary, sublimation method.

[0045]

EXAMPLES The features of the present invention will be described more specifically below with reference to examples and reference examples. Materials shown in the following examples,
The usage amount, ratio, processing content, processing procedure, etc. can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be limitedly interpreted by the following specific examples.

Example 1 (Synthesis of Exemplified Compound (I-1))

[Chemical 14]

<Synthesis of 1-benzyloxy-4-chlorobutane (B-1)> (B-1) is described in Tetrahedron Lett., 3
2,5051 (1991), J.Org.Chem., 36,3526 (1971), J.Chem.So
It was synthesized as follows with reference to c.PerkIn.Trans.I, 1994,837. Butane-1,4-diol 90.1 g
51.0 g of potassium hydroxide (1.0 mol) (1.0 mol)
5 mol) was added and stirred. Benzyl bromide 17 into it
1.0 g (1.0 mol) was added dropwise over about 1 hour.
The internal temperature was 40 to 50 ° C. After stirring overnight, 2.0 L of water
And 1.0 L of ethyl acetate were added to separate the aqueous layer, and the ethyl acetate layer was washed with water (once) and saturated saline solution (once). After drying over anhydrous sodium sulfate, filtration and concentration gave 132.5 g of 4- (benzyloxy) butan-1-ol having a purity of 94.7% (HPLC) (yield 7
3.5%) was obtained.

129.8 g (0.72 mol) of 4- (benzyloxy) butan-1-ol and 70 ml of pyridine
Were mixed and stirred under a nitrogen stream. Thionyl chloride (104.5 ml) was added dropwise thereto at 75 ° C. or lower over 1 hour.
After the plucking, the mixture was stirred at 80 to 90 ° C. for 2 hours, after which heating was stopped and the mixture was left overnight. The reaction product was poured little by little into 1.1 L of ice water, extracted with 1 L of ethyl acetate, washed with water (once) and saturated saline solution (once), and then dried over anhydrous sodium sulfate. After filtration and concentration under reduced pressure, 115 g of (B-1) was obtained as an oil (HPLC purity 96.3%). Yield 80.3%.

<Synthesis of (C-1)> 2-Methyl-5-cyclohexyl-6-hydroxybenzoxazole (A
-1) was synthesized according to the method described in JP-A-56-100771. (A-1) 46.1 g (0.2 mo
l) was dissolved in 120 ml of dimethylformamide (DMF) by heating (internal temperature: 54 ° C.). The mixture was cooled with water to an internal temperature of 36 ° C., and 16 g (0.4 mol) of sodium hydroxide was added dividedly in four portions. Heat was generated and the internal temperature rose to 47 ° C. Next, the external temperature is set to 55 ° C (internal temperature 52 ° C), and (B-
1) 43.7 g (0.22 mol) was added dropwise over about 8 minutes. The internal temperature rose to 60 ° C. Next, the external temperature was set to 70 ° C. and the mixture was stirred for about 5 hours. Then, the mixture was cooled to room temperature with water, neutralized by adding 18 ml (0.21 ml) of 36% hydrochloric acid, and then 300 ml of ethyl acetate, 300 ml of water and a small amount of salt were added for extraction. Separate the ethyl acetate layer,
It was washed with water (3 times) and saturated saline (1 time), dried over magnesium sulfate, filtered, and concentrated under reduced pressure. In this way, 68.6 g of the crude (C-1) as a viscous oily substance was obtained.
(About 87%) was obtained.

<Synthesis of (D-1)> The obtained crude (C-
1) was dissolved in 300 ml of methanol without purification, and was heated under reflux with 52.4 ml of 36% hydrochloric acid (0.61mo
1) was added dropwise (about 5 minutes). After heating and refluxing for 3 hours, methanol was distilled off under reduced pressure (using an aspirator), and then toluene / ethyl acetate (methanol if necessary) was added to the residue to remove water as much as possible by azeotropic distillation. In this way (D-1)
The crude product of was obtained.

<Synthesis of (F-1)> The obtained crude (D-
Dimethylacetamide (DMAC) 300 in 1)
After adding ml to the solution to dissolve it with heating, the mixture was cooled with water to room temperature and 17.7 g (87.2 mmol) of terephthaloyl chloride was added. A little heat was generated and the temperature rose from 20 ° C to 29 ° C.
After stirring for about 30 minutes as it was, the mixture was heated to an external temperature of about 45 ° C. and stirred, 600 ml of methanol was added, and the mixture was stirred for about 10 minutes and cooled with water to an internal temperature of about 17 ° C. After 1 hour, the precipitated crystals were filtered and washed with ice-cooled methanol. By drying, 47.0 g of (F-1) was obtained as almost pure yellow crystals.
(54.1% yield from (A-1)) was obtained.

<Synthesis of Exemplified Compound (II-1)> (F-
1) 43.5 g (0.05 mol) and p-toluenesulfonic acid monohydrate 9.5 g (0.05 mol) were heated and refluxed in toluene (250 ml) for about 10 hours. in the meantime,
The Dean Stark apparatus was used to remove the water produced. 300 ml of methanol was added to the reaction solution, and the mixture was stirred for 5 hours under cooling with water. The precipitated yellow crystals were separated by filtration and recrystallized from tetrahydrofuran / methanol (3: 1) to give 3x of the exemplary compound (II-1) as pale yellow crystals.
0.3 g (yield 72.8%) was obtained. Melting point 147-150
° C.

<Synthesis of Exemplified Compound (I-1)> 25.0 g (0.03 mol) of Exemplified Compound (II-1) was placed in an autoclave, and 300 ml of DMAC and 1.0 g of 5% Pd-C catalyst were added to the lid. Did. After removing the air in the container with an aspirator, introduce hydrogen into it to increase the internal pressure to 5
It was set to kg / m ² . Then, the mixture was stirred at 50 ° C. for about 5 hours and then cooled to room temperature. After exhausting hydrogen and returning to normal pressure, the catalyst was removed by filtration, and the filtrate was concentrated under reduced pressure to about 100 ml. Next, add 300 mL of methanol while stirring the concentrate.
After adding ml, and stirring for about 1 hour, the precipitated crystals were separated by filtration and washed with methanol. By drying, 15.7 g (yield 80.0%) of exemplary compound (I-1) was obtained as pale yellow crystals. Melting point 245-246 [deg.] C.

Example 2 (Synthesis of Exemplified Compound (II-2)) 13.1 g (0.02 ml) of Exemplified Compound (I-1) was suspended in 200 ml of tetrahydrofuran, and 4.0 g (0.05 mol of pyridine) was suspended therein. ) Was added. The mixture was heated and stirred at about 50 ° C., in which 2- (3,6-di-t-butyl-
4-Methoxyphenoxy) butyroyl chloride 13.6
g (0.04 mol) was dissolved in 20 ml of tetrahydrofuran, added dropwise over 30 minutes, and then stirred for 1 hour. Then, after heating under reflux for 1 hour, the temperature is returned to room temperature, and toluene 200 is added.
ml and 200 ml of water were added and stirred. The reaction solution was transferred to a separatory funnel, the aqueous layer was removed, the mixture was washed with water (once) and saturated brine (once), and the organic layer was dried over magnesium sulfate. After separation by filtration and concentration under reduced pressure, the obtained crude product was recrystallized with a mixed solvent of ethyl acetate / n-hexane to give the exemplified compound (II
21.4 g (yield 85%) was obtained. Melting point 70-7
3 ° C.

Example 3 (Synthesis of Exemplified Compound (II-14)) 130.6 g (0.2) of Exemplified Compound (I-1) was placed in a polymerization vessel.
mol), 47 g of diphenyl carbonate (0.22 m
ol) and 0.04 g (0.5 mmol) of zinc oxide were added and the mixture was heated and melted in a nitrogen atmosphere. Phenol began to distill at an internal temperature of about 190 ° C. The pressure was adjusted to 50 mmHg and the phenol was distilled off at this temperature for 30 minutes. Next, the pressure is reduced to 15 mmHg and the temperature is about 210 ° C for 30 minutes at 1 mmH.
Heating was continued at g for 30 minutes. Further under this pressure about 220
30 minutes at ℃, 2 hours at about 250 ℃, finally about 270 ℃
Heated for 1 hour. The product solidified on cooling. 150 ml of dichloromethane was added thereto and stirred, and 500 ml of methanol was added dropwise thereto. After dropping, the mixture was stirred for 10 minutes, the polymer was filtered off, and dried at 100 ° C. for 15 hours.
Thus, 133.5 g of the exemplified compound (II-14) was obtained.

Reference Example 1 (Comparison of Solubility) Table 1 shows the solubilities of the compound of the present invention and the comparative compounds (A) to (E). Toluene and ethyl acetate were used as the solvent. It can be seen that the compounds of the present invention have significantly improved solubility as compared with the comparative compounds (A) to (E).

[0057]

[Table 1]

[0058]

[Chemical 15]

Reference Example 2 (Comparison of Lightfastness) The compound of the present invention and the comparative compounds (A) to (E) are dissolved in dichloromethane and coated on a glass for preparation, and the solvent is volatilized to form a thin film. Formed. Then, a xenon lamp (100,000 lux) was irradiated from the glass side, and the change in absorbance at 400 nm was observed. The results are shown in Table 2. It was confirmed that the compounds of the present invention have improved light fastness.

[0060]

[Table 2]

Reference Example 3 (Use as fluorescent whitening agent) In Example 1 described in JP-A-8-231808, the fluorescent whitening agent 4,4'-bis (5-methyl-2-benzoxazolyl) ) Exemplified compounds (II instead of stilbene
-1), (II-4) or (II-7) was used in the same manner except that 0.3 ppm was used to prepare three types of sidelight type illumination devices. Also, the same one as in Example 1 was manufactured,
When the color coordinates thereof were evaluated, the results using the compound of the present invention showed that the color unevenness was almost equal to or higher than that of Example 1 and the brightness was high.

Reference Example 4 (Use as Light Wavelength Converting Material) In Example 5 described in JP-A-4-144618, the compound (2) (2- [4- (4,6-
Diphenyl-1,3,5-triazin-2-yl) phenyl] -5,6-dimethylbenzoxazole) instead of the exemplified compounds (II-2), (II-3), (II
Four types of films were produced in the same manner except that 0.5 part by weight of -6) or (II-16) was used. Also, the same films as in Example 5 were produced, and they were lined up outdoors and exposed to the sun to obtain their light fastness (fluorescence intensity and fluorescence activity retention rate).
Were compared. As a result, all the films using the compound of the present invention are described in Example 5 of JP-A-4-144618.
It showed superior lightfastness to the films described in.

Reference Example 5 (Use as UV Cut Material) In Example 1 described in JP-A-2002-53824, the compound of formula (1) (2,2 ′-(1,2-ethenediyl) bis (5- UV absorbing transparent pressure-sensitive adhesive sheet in the same manner except that 10% by mass of Exemplified Compound (II-4), (II-8), (II-10) or (II-12) is used instead of (methylbenzoxazole)). Was prepared. Also, the same sheet as in Example 1 was prepared, and they were attached to a glass plate and the absorption spectrum was measured. The sheet using the compound of the present invention has less yellow tint than the sheet of Example 1 and cuts to 410 nm. The performance was shown.

[0064]

INDUSTRIAL APPLICABILITY The bisbenzoxazole compound of the present invention is excellent in solubility and light fastness, and can be expanded in its use as a fluorescent whitening material, a light wavelength conversion material or an ultraviolet ray cutting material.

Claims (2)

[Claims] 1. A bisbenzoxazole compound represented by the general formula (I). [Chemical 1] (In the formula, Ar is a substituted or unsubstituted p-phenylene group, 1,4-naphthylene group, 1,5-naphthylene group,
It represents a 4,4′-biphenylene group, a 4,4 ″ -p-terphenylene group, a 4,4 ′ ″-p-quataphenylene group or a 2,5-thiophenediyl group. R ¹ and R ² each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group. m and n each independently represent an integer of 2 or more. ) 2. A bisbenzoxazole compound represented by the general formula (II). [Chemical 2] (In the formula, Ar is a substituted or unsubstituted p-phenylene group, 1,4-naphthylene group, 1,5-naphthylene group,
It represents a 4,4′-biphenylene group, a 4,4 ″ -p-terphenylene group, a 4,4 ′ ″-p-quataphenylene group or a 2,5-thiophenediyl group. R ¹ and R ² each independently represent a hydrogen atom or a substituted or unsubstituted alkyl group. R ³ and R ⁴ each independently represent a substituted or unsubstituted alkyl group, aryl group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylaminocarbonyl group or arylaminocarbonyl group. m and n each independently represent an integer of 2 or more. )