JP2022121884A - Dihydroxy compound and production method thereof - Google Patents

Abstract

To provide: a novel dihydroxy compound having high purity, no coloration, and a high refractive index; and a production method thereof.SOLUTION: Provided is a dihydroxy compound represented by the following formula (1). (In the formula, Z1 is a heterocyclic group containing a sulfur atom; L1 is an alkylene group having 1-15 carbon atoms; m1 is an integer of 0-5; and n1 is an integer of 1-4.)SELECTED DRAWING: None

Description

The present invention relates to a dihydroxy compound and a method for producing the same.

Compared to inorganic materials such as glass, plastic optical materials are lightweight, resistant to cracking, and easy to process. is expected. However, current plastic optical materials have many problems to be solved. For example, in lens applications, characteristics such as a high refractive index are required, but the refractive index of plastic lenses currently in practical use does not reach the refractive index of high refractive index glass materials, and further performance improvement is required. It is Under such circumstances, dihydroxy compounds containing dinaphthothiophene have been shown to have a high refractive index, which is rare among organic compounds (Patent Document 1). However, the compound is colored as described in the examples, and there is a problem in using it as a raw material for a thermoplastic resin that is a raw material for lenses. In addition, there are problems such as the need for many manufacturing processes until obtaining the compound, the use of raw materials that have the risk of ignition or explosion, and the need for a high-temperature reaction of about 250°C.

JP 2014-196288 A

An object of the present invention is to provide a novel dihydroxy compound having high purity, no coloration, and a high refractive index, and a method for producing the same.

The inventors have found that the above problems can be solved by the present invention having the following aspects.
<<Aspect 1>>
A dihydroxy compound represented by the following formula (1).

（式中、Ｚ_１は硫黄原子を含む複素環基、Ｌ_１は炭素原子数１～１５のアルキレン基、ｍ_１は０～５の整数、ｎ_１は１～４の整数である。）

(In the formula, Z ₁ is a heterocyclic group containing a sulfur atom, L ₁ is an alkylene group having 1 to 15 carbon atoms, m ₁ is an integer of 0 to 5, and n ₁ is an integer of 1 to 4.)

<<Aspect 2>>
The dihydroxy compound according to aspect 1, represented by the following formula (2).

（式中、Ｚ_１、Ｌ_１、ｍ_１は前記式（１）と同様である。）

(In the formula, Z ₁ , L ₁ and m ₁ are the same as in formula (1) above.)

<<Aspect 3>>
The dihydroxy compound according to aspect 1 or 2, represented by the following formula (3).

（式中、Ｚ_２はジベンゾチオフェニル基であり、Ｌ_１、ｍ_１は前記式（１）と同様である。）

(In the formula, Z ₂ is a dibenzothiophenyl group, and L ₁ and m ₁ are the same as in formula (1) above.)

<<Aspect 4>>
The dihydroxy compound according to any one of Embodiments 1 to 3, represented by the following formula (4).

（式中、Ｌ_１、ｍ_１は前記式（１）と同様である。）

(In the formula, L ₁ and m ₁ are the same as in formula (1) above.)

<<Aspect 5>>
5. The dihydroxy compound according to any one of aspects 1 to 4, wherein m ₁ in the formula is 0.
<<Aspect 6>>
The dihydroxy compound according to any one of aspects 1 to 5, which has a refractive index of 1.70 or more.
<<Aspect 7>>
Production of the dihydroxy compound according to aspect 1, wherein a diol represented by the following formula (5) and a boronic acid represented by the following formula (6) are reacted in a reaction solvent in the presence of a base and a palladium-based catalyst. Method.

（式中、Ｘ_１はハロゲン原子であり、Ｌ_１は炭素原子数１～１５のアルキレン基、ｍ_１は０～５の整数、ｎ_１は１～４の整数である。）

(In the formula, X ₁ is a halogen atom, L ₁ is an alkylene group having 1 to 15 carbon atoms, m ₁ is an integer of 0 to 5, and n ₁ is an integer of 1 to 4.)

（式中、Ｙ_１は硫黄原子を含む複素環基である。）

(In the formula, Y ₁ is a heterocyclic group containing a sulfur atom.)

<<Aspect 8>>
The method for producing a dihydroxy compound according to aspect 7, wherein the diol represented by formula (5) is represented by formula (7) below.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a thiophene-containing dihydroxy compound that is highly pure, colorless, and has a high refractive index. Moreover, it is possible to provide a production method for obtaining the dihydroxy compound in one reaction step.

1 shows an NMR chart of the dihydroxy compound obtained in Example 1. FIG.

<Dihydroxy compound>
A novel dihydroxy compound in the present invention is represented by the following formula (1).

（式中、Ｚ_１は硫黄原子を含む複素環基、Ｌ_１は炭素原子数１～１５のアルキレン基、ｍ_１は０～５の整数、ｎ_１は１～４の整数である。）

(In the formula, Z ₁ is a heterocyclic group containing a sulfur atom, L ₁ is an alkylene group having 1 to 15 carbon atoms, m ₁ is an integer of 0 to 5, and n ₁ is an integer of 1 to 4.)

n ₁ in formula (1) is an integer of 1 to 4, preferably an integer of 1 to 2, and particularly preferably 2. That is, among dihydroxy compounds represented by formula (1), dihydroxy compounds represented by the following formula (2) are particularly preferred.

（式中、Ｚ_１、Ｌ_１、ｍ_１は前記式（１）と同様である。）

(In the formula, Z ₁ , L ₁ and m ₁ are the same as in formula (1) above.)

Z ₁ in formulas (1) and (2) is a heterocyclic group containing a sulfur atom, and includes, for example, thienyl, benzothiophenyl, dibenzothiophenyl, etc. Dibenzothiophenyl is particularly preferred. . That is, among dihydroxy compounds represented by formula (2), dihydroxy compounds represented by the following formula (3) are particularly preferred.

（式中、Ｚ_２はジベンゾチオフェニル基であり、Ｌ_１、ｍ_１は前記式（１）と同様である。）

(In the formula, Z ₂ is a dibenzothiophenyl group, and L ₁ and m ₁ are the same as in formula (1) above.)

Z ₂ in formula (3) is a dibenzothiophenyl group, including dibenzothiophen-1-yl group, dibenzothiophen-2-yl group, dibenzothiophen-3-yl group and dibenzothiophen-4-yl group. , the dibenzothiophen-2-yl group is particularly preferred. That is, among dihydroxy compounds represented by formula (3), dihydroxy compounds represented by the following formula (4) are particularly preferred.

（式中、Ｌ_１、ｍ_１は前記式（１）と同様である。）

(In the formula, L ₁ and m ₁ are the same as in formula (1) above.)

L ₁ in formulas (1) to (4) is an alkylene group having 1 to 15 carbon atoms, preferably an alkylene group having 1 to 12 carbon atoms, more preferably an alkylene group having 1 to 4 carbon atoms, Ethylene groups are particularly preferred.
m ₁ in formulas (1) to (4) is an integer of 0 to 5, preferably 0 or 1, more preferably 0.

The dihydroxy compound of the present invention preferably has an HPLC purity measured by HPLC of 90 area % or more, more preferably 95 area % or more, and even more preferably 98 area % or more.

The dihydroxy compound of the present invention preferably has a refractive index of 1.70 or higher, more preferably 1.71 or higher, and even more preferably 1.72 or higher. The refractive index is determined by dissolving a dihydroxy compound in dimethyl sulfoxide to prepare a solution with a predetermined concentration, and measuring the refractive index of the solution at each concentration using a DR-M2 Abbe refractometer manufactured by ATAGO Co., Ltd., and measuring the D-line refractive index at 25°C. The refractive index (nD) of the compound obtained by extrapolating from the measurement result of each concentration to the concentration of 100% was defined as the refractive index (nD).

<Method for producing dihydroxy compound>
The dihydroxy compound of the present invention is obtained by reacting a diol represented by the following formula (5) and a boronic acid represented by the following formula (6) in a reaction solvent in the presence of a base and a palladium-based catalyst, A dihydroxy compound represented by (1) can be produced.

(In the formula, X ₁ is a halogen atom, L ₁ is an alkylene group having 1 to 15 carbon atoms, m ₁ is an integer of 0 to 5, and n ₁ is an integer of 1 to 4.)

（式中、Ｙ_１は硫黄原子を含む複素環基である。）

(In the formula, Y ₁ is a heterocyclic group containing a sulfur atom.)

X ₁ in formula (5) is a halogen atom, preferably a chlorine atom or a bromine atom, more preferably a bromine atom.

Specific examples of diols represented by formula (5) include 2,2-bis(3-chloro-4-hydroxyphenyl)propane and 2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane. , 2,2-bis(3-bromo-4-hydroxyphenyl)propane, 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane, 2,2-bis(3-iodo-4-hydroxy Phenyl)propane, 2,2-bis(3,5-diiodo-4-hydroxyphenyl)propane are preferred, and 2,2-bis(3-bromo-4-hydroxyphenyl)propane, 2,2-bis(3, 5-Dibromo-4-hydroxyphenyl)propane is more preferred, and 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane represented by the following formula (7) is particularly preferred. These diols may be used alone or in combination of two or more, and can be arbitrarily selected depending on the purpose.

Specific examples of boronic acids represented by the formula (6) include 2-thiophene boronic acid, 3-thiophene boronic acid, benzothiophene-2-boronic acid, benzothiophene-3-boronic acid, and benzothiophene-4-boron. acid, benzothiophene-5-boronic acid, benzothiophene-6-boronic acid, benzothiophene-7-boronic acid, dibenzothiophene-2-boronic acid, dibenzothiophene-3-boronic acid, dibenzothiophene-4-boronic acid Dibenzothiophene-2-boronic acid, dibenzothiophene-3-boronic acid and dibenzothiophene-4-boronic acid are preferred, and dibenzothiophene-2-boronic acid is particularly preferred. Moreover, boronic acid esters and boronic acid anhydrides of these compounds are also included as boronic acids. These boronic acids may be used alone or in combination of two or more, and can be arbitrarily selected depending on the purpose.

The use ratio of the boronic acid represented by the above formula (6) used as a raw material is preferably 2.0 to 6.0 mol, more preferably, per 1 mol of the diol compound represented by the above formula (5). 3.0 to 5.0 mol, more preferably 4.0 to 4.5 mol.

Examples of the base used in the production method of the present invention include hydroxides such as sodium hydroxide and potassium hydroxide, sodium carbonate (Na ₂ CO ₃ ), potassium carbonate (K ₂ CO ₃ ), cesium carbonate (Cs ₂ carbonates such as CO ₃ ), acetates such as sodium acetate and potassium acetate, inorganic salts such as phosphates such as sodium phosphate (Na ₃ PO ₄ ) and potassium phosphate (K ₃ PO ₄ ), triethylamines, Examples include organic salts such as pyridine, morpholine, quinoline, piperidine, anilines, and ammonium salts such as tetra-n-butylammonium acetate. Among them, carbonate is preferably used, and potassium carbonate and/or sodium carbonate are preferred. Such bases may be used alone, or two or more of them may be used in combination.

The amount of the base used is not particularly limited, but it is preferably added in an amount of 1 to 30 equivalents, more preferably 1 to 10 equivalents, per 1 mol of the boronic acid.

Palladium-based catalysts used in the production method of the present invention are preferably palladium compounds used in Suzuki coupling, such as tetrakis(triphenylphosphine)palladium, bis(triphenylphosphine)palladium dichloride, palladium acetate, tris( Dibenzylideneacetone)dipalladium, bis(dibenzylideneacetone)palladium, bis[4-(N,N-dimethylamino)phenyl]di-tert-butylphosphinepalladium dichloride, bis(di-tert-butylprenylphosphine)palladium dichloride , bis(di-tert-crotylphosphine)palladium dichloride, palladium-based catalyst represented by Pd/SiO ₂ and the like. Among them, tetrakis(triphenylphosphine)palladium is preferred. These palladium-based catalysts may be used alone, or two or more of them may be used in combination.

The amount of the catalyst used is not particularly limited, but it is preferably 0.1 to 50 mmol, more preferably 0.1 to 50 mmol in terms of palladium metal atom, per 1 mol of the diol compound represented by the formula (5). 5 to 30 millimoles.

The reaction solvent used in the production method of the present invention is not particularly limited. For example, aromatic hydrocarbon solvents such as toluene and xylene and alcohols such as methanol, ethanol, isopropyl alcohol and n-butanol are They can be used alone or in combination. Since the aromatic hydrocarbon solvent is a solvent with a high boiling point, the reaction temperature can be set high, and by using an alcohol, it has good affinity with water and good reactivity, so that it is preferably used. Such solvents may be used alone, or two or more of them may be used in combination. Furthermore, aprotic solvents such as N,N-dimethylformamide or N,N-dimethylacetamide and halobenzenes such as o-dichlorobenzene can also be used. Such solvents may be used alone, or two or more of them may be used in combination. In the present invention, a mixed solvent of toluene and ethanol is more preferred.

The amount of the reaction solvent used is not particularly limited, but is preferably 0.1-fold or more by weight, more preferably 0.5 to 100-fold by weight, relative to 1 mol of the diol compound represented by the formula (5). Yes, more preferably 1 to 50 times the weight.

In the case of a mixed solvent of toluene and ethanol, which is particularly preferably used as the reaction solvent, the amount of toluene used is preferably 0.1 times the weight of 1 mol of the diol compound represented by the above formula (5). Above, more preferably 0.5 to 100 times the weight, still more preferably 1 to 50 times the weight. The amount of ethanol used is preferably 0.1 to 50 times by weight, more preferably 1 to 20 times by weight, relative to 1 mol of the compound represented by the formula (5).

In the production method of the present invention, the reaction temperature varies depending on the raw material and solvent used, but is preferably 50 to 150°C, more preferably 60 to 130°C, and even more preferably 70 to 120°C. The reaction can be followed by analytical means such as liquid chromatography.

In the production method of the present invention, the reaction mixture after completion of the reaction usually contains unreacted boronic acids, bases, catalysts, side reaction products, etc., in addition to the produced dihydroxy compound represented by the formula (1). include. Therefore, conventional methods such as filtration, concentration, extraction, crystallization, recrystallization, reprecipitation, activated carbon treatment or similar metal removal treatment, column chromatography, or a combination of these separation means It can be separated and purified. For example, remove boronic acids by a conventional method (such as adding an aqueous alkaline solution to form a water-soluble complex), remove the palladium compound by performing activated carbon treatment or a similar metal removal treatment, and then re- It is preferable to purify by adding a crystallization solvent, cooling to recrystallize, and then separating by filtration.

EXAMPLES Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded.
In the examples, various measurements were performed as follows.
(1) HPLC measurement Measured under the measurement conditions shown in Table 1 using a high-performance liquid chromatograph L-2350 manufactured by Hitachi. In the examples, unless otherwise specified, % is the area percentage value corrected by removing the solvent in HPLC.

(2) NMR measurement The compounds obtained in the examples were dissolved in heavy chloroform and measured using JNM-AL400 (400 MHz) manufactured by JEOL Ltd.
(3) refractive index (nD)
The dihydroxy compound obtained in the example is dissolved in dimethyl sulfoxide to prepare a solution of a predetermined concentration, and the refractive index of the solution of each concentration is measured using a DR-M2 Abbe refractometer manufactured by ATAGO Co., Ltd. The D-line refractive index at 25 ° C. was measured. The refractive index (nD) of the compound obtained in the example was defined as a value extrapolated from the measurement result of each concentration to the concentration of 100%.

[Example 1]
In a nitrogen atmosphere, 3.00 g (6 mmol) of tetrabromobisphenol A (hereinafter sometimes abbreviated as TBA) and 2.77 g of dibenzothiophene-2-boronic acid were placed in a flask equipped with a stirrer, condenser, and thermometer. (12 millimoles), 0.06 g (0.06 millimoles) of tetrakis(triphenylphosphine)palladium, 12 ml of 2M potassium carbonate aqueous solution, 25 ml of toluene and 8 ml of ethanol were added and reacted at 80° C. for 4 hours. Thereafter, 0.06 g (0.06 mmol) of tetrakis(triphenylphosphine)palladium and 2.77 g (12 mmol) of dibenzothiophene-2-boronic acid were added and reacted at 80° C. for 4 hours. After completion of the reaction, the reaction solution was diluted with ethyl acetate, transferred to a separating funnel, and washed with distilled water until neutral. Thereafter, hexane was added to the organic layer for recrystallization. The obtained crystals are collected and dried under reduced pressure to give 2,2-bis(3,5-di(dibenzothiophen-2-yl)-4-hydroxyphenyl)propane represented by the following formula (8) (hereinafter , sometimes abbreviated as TDBTA) was obtained (purity 71%). The crude product was column-purified (developing solvent: ethyl acetate:hexane=1:3), and the obtained eluate was concentrated and then recrystallized. The obtained crystals were collected and dried under reduced pressure to obtain 0.6 g of white crystals of TDBTA (98.21% purity). Moreover, the refractive index of TDBTA was 1.727.

[Comparative Example 1]
The following formula (9 ) to give 2,2-bis(3,5-diphenyl-4-hydroxyphenyl)propane. The refractive index of the compound was 1.65.

The novel dihydroxy compound obtained in Example 1 has a high refractive index, high purity, and excellent hue. Moreover, such a dihydroxy compound can be produced in one reaction step, and is industrially useful.

The novel dihydroxy compound obtained in the present invention is suitable as a monomer for forming a resin that constitutes optical members such as optical lenses and optical films.

Claims (8)

A dihydroxy compound represented by the following formula (1).

(In the formula, Z ₁ is a heterocyclic group containing a sulfur atom, L ₁ is an alkylene group having 1 to 15 carbon atoms, m ₁ is an integer of 0 to 5, and n ₁ is an integer of 1 to 4.) The dihydroxy compound according to claim 1, represented by the following formula (2).

(In the formula, Z ₁ , L ₁ and m ₁ are the same as in formula (1) above.) The dihydroxy compound according to claim 1 or 2, represented by the following formula (3).

(In the formula, Z ₂ is a dibenzothiophenyl group, and L ₁ and m ₁ are the same as in formula (1) above.) The dihydroxy compound according to any one of claims 1 to 3, represented by the following formula (4).

(In the formula, L ₁ and m ₁ are the same as in formula (1) above.) 5. The dihydroxy compound according to any one of claims 1 to 4, wherein m ₁ in said formula is 0. The dihydroxy compound according to any one of claims 1 to 5, which has a refractive index of 1.70 or more. The dihydroxy compound according to claim 1, wherein a diol represented by the following formula (5) and a boronic acid represented by the following formula (6) are reacted in a reaction solvent in the presence of a base and a palladium-based catalyst. Production method.

(In the formula, X ₁ is a halogen atom, L ₁ is an alkylene group having 1 to 15 carbon atoms, m ₁ is an integer of 0 to 5, and n ₁ is an integer of 1 to 4.)

(In the formula, Y ₁ is a heterocyclic group containing a sulfur atom.) 8. The method for producing a dihydroxy compound according to claim 7, wherein the diol represented by formula (5) is represented by formula (7) below.

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