JPH01228983A - Bithienylidenebisbenzoquinones and production thereof - Google Patents

Abstract

NEW MATERIAL:A compound shown by formula I (R<1>-R<4> are H or 1-8C alkyl). EXAMPLE:Bithienylidenebisbenzoquinone. USE:A near infrared ray absorbing agent. A light recording medium, an organic sensitized material, optical guard, television, light absorbing material or outer near infrared light screening material of control mechanism of sound devices, protecting glasses for laser processing, material for screening heat radiation, etc. PREPARATION:Two molecules of thienylphenols shown by formula II are coupled in the presence of an oxidizing agent (e.g., potassium permanganate) to give a compound shown by formula I. The starting raw material can be produced by silylating iodophenol shown by formula III with a silylating agent such as trimethylsilyl chloride to give iodo trimethylsiloxybenzene shown by formula IV, which is then reacted with thienylzinc chloride shown by formula V.

Description

[Detailed Description of the Invention] [Industrial Application Field] In recent years, many energy systems, information recording systems, and equipment control systems that utilize light in the near-infrared region have been developed.

The compounds of this invention relate to near-infrared absorbers that can be utilized in these systems.

More specifically, optical recording media, organic photoreceptors, optical cards, materials for light absorption or shielding of external near-infrared light for control mechanisms such as televisions and audio equipment, protective goggles for laser processing, and heat rays for growth control. This invention relates to blocking materials and compounds that can be used in other fields.

[Prior Art] In recent years, research on optical recording means using organic compounds has been actively conducted.

There are many methods for optical recording, but the one that is currently closest to practical use is one in which focused light is irradiated onto the recording medium and converted into thermal energy, and the heat causes the recording medium to change shape. There is a method in which the changes in shape are scanned with light that is sufficiently weakened so as not to damage the recording medium layer, and the changes in the reflected light are detected and the recorded information is reproduced.

Examples of compounds that can be used as recording media of this type include "Dye and Medicine" Vol. 30, No. 11, 3.
Pages 08-318 describe the use of intramolecular charge transfer complexes as described on the next page.

In addition, near-infrared absorbers include cyanine dyes (JP-A-56-46221.58-112790), phthalocyanine dyes (JP-A-58-36490), naphthoquinone dyes (JP-A-6O-15458), and anthraquinone dyes (JP-A-6O-15458). JP-A-61-291651) and dithiol complexes (JP-A-58-175693) are known.

However, anthraquinone and naphthoquinone dyes have a small molar extinction coefficient of about several hundred.

Furthermore, dithiol complexes have major drawbacks such as insufficient thermal stability and molar extinction coefficient.

[Problems to be Solved by the Invention] This invention was completed in order to solve the above-mentioned problems. The purpose is to provide absorbent substances.

[Means for Solving the Problems] As a result of intensive research and examination of cross-conjugated compounds, the inventors discovered novel bithienylidene bisbenzoquinones that have absorption ability in the long wavelength region, and accomplished this invention. It was completed.

Bithienylidene bisbenzoquinones of the present invention represented by the following maximum (1) [in formula (1), R1, RZ, R3, and R4 are each independently a hydrogen atom or a straight chain having 1 to 8 carbon atoms; Or display a branched alkyl group. ] can be produced as follows.

That is, Equation (3) on the next page [In Equation (3), R1 and R2 are R1 and 8 of Equation (1).
It means the same group as 2. ] The iodized phenol represented by is silylated with a silylating agent such as trimethylsilyl chloride to form the formula (4) [In formula (4), R' and R2 are R1 and R2 of formula (1)
means the same group as . ] Iodinated trimethylsiloxybenzene is synthesized, and then the formula (5) [In the formula (5), R3 and R4 mean the same groups as R3 and R4 in the formula (1). ] The following formula (2) obtained by reacting with thienyl zinc chloride represented by [In formula (2), R', R", R" and R4 are
It means the same groups as R1, R2, R3 and R4 in 1). Bithienylidene bisbenzoquinone is produced by coupling two molecules of the thienylphenol shown in ] in the presence of an oxidizing agent.

Oxidizing agents used for coupling include inorganic oxidizing agents such as potassium permanganate, manganese dioxide, chromic acid, potassium dichromate, sodium dichromate, potassium ferricyanide, ferric chloride, oxygen, and peroxide. Either hydrogen alone or an oxidizing system in the presence of a catalyst, or an organic oxidizing agent such as dicyanodichlorobenzoquinone or chloranil may be used, but potassium ferricyanide is preferable from the viewpoint of cost or industrial use.

In addition, the reaction can be carried out by suspension in water, suspension in an organic solvent, or
Although the reaction may be carried out using any reaction system such as a water-organic solvent two-phase system, the yield is particularly good when a water-benzene two-phase system is used.

[Example] This invention will be specifically explained by examples.

[Synthesis of 2,6-di-t-butyl-4-iodotrimethylsiloxybenzene 1 2.6-di-t-butyl-4-iodophenol (25
,0 g, 75.25 mmol) in dry tetrahydrofuran (THF) (90 ml) at -78 °C under an argon atmosphere. ．．
9 ml, 75.25 mmol) was added dropwise to -78°C.
After stirring for 10 minutes at -78°C, trimethylsilyl chloride (19.1 ml, 150.5 mmol) was added, stirred at -78°C for 10 minutes, and then warmed to room temperature. Extract by adding ether and water and extract the ether phase with water,
Next, wash with saturated saline, add anhydrous sodium sulfate, and dry.

The solvent was removed, and the residue was purified by silica gel chromatography (n-hexane) to yield white crystals of 2,6-di-t-butyl-4-iodotrimethylsiloxybenzene at 26.7 g.
8 g (yield 88.0%) was obtained.

When recrystallized from methanol, this white crystal has a melting point of 12
It became a pure product with a temperature of 7-130°C.

Synthesis of [2,6-di-tert-butyl-4-(2-thienyl)trimethylsiloxybenzene 1] Thiophene (3,52 g, 41.79 mmol) was dissolved in 50 ml of dry ether at 0° C. under an argon atmosphere. n-hexane solution of n-butyllithium (1,64M concentration: 25.5 ml, 41.79
mmol) and stir for 1 hour. This thienyl lithium compound was mixed with zinc chloride (5.70 g, 41.7
9 mmol) in dry THF (50 ml) and stirred for 1 hour at 0° C. to give thienyl zinc chloride. Another container i: PdC
1z (PPbs) a (1,13g.

1.607 mmol), dry THF (50 ml)
, and diisobutylaluminum hydride (DI
BAH) n-hexane solution (IM concentration: 3.22m
1.3.215 mmol) was added and stirred, and to this was added 2.6-di-t-butyl-4-(2-thienyl)trimethylsiloxybenzene (13.0 g, 32.15 mmol).
mmol) of dry T HF (100 ml) was added and stirred for 30 minutes. Next, the supernatant liquid of the thienyl zinc chloride solution prepared previously was added to this at room temperature, and the mixture was stirred for 30 minutes.

Extract with ether, wash the ether phase with water, then with saturated brine, and dry over anhydrous sodium sulfate.
The solvent was removed and the residue was purified by silica gel chromatography (n-hexane) to give 2,6-di-t-butyl-4-
9.90 g (yield: 85.4%) of (2-thienyl)trimethylsiloxybenzene white crystals were obtained.

Furthermore, it was recrystallized from methanol and the melting point was 88-89℃.
It is a pure product.

[Synthesis of 2,6-di-t-butyl-4-(2-thienyl)phenol 1 2.6-di-t-butyl-4-(2-thienyl)trimethylsiloxybenzene (90 mg, 0.249 mm
12NHCl (1 ml) was added to a solution of ol) dissolved in acetonitrile (11 ml), and the mixture was stirred at room temperature for 1 hour. Acetonitrile is removed, ether is added to the residue, and the ether phase is washed with water and then with saturated saline and dried over anhydrous sodium sulfate.

The solvent was removed and the residue was purified by silica gel chromatography (n-hexane) to give a product with a melting point of 2.6°C, mp 54-55°C.
65 mg (yield 90.5%) of a colorless solid of -di-t-butyl-4-(2-thienyl)phenol was obtained.

[Synthesis of bithienylidene bisbenzoquinone 12.6-di-t-butyl-4-(2-thienyl)phenol (67
mg, 0.232 mmol) in benzene (4 ml)
0.1N K leaf aqueous solution (8ml) and potassium ferricyanide (764mg, 2.32ml)
mol) and stirred vigorously at room temperature for 4 hours. Extract by adding benzene and water, wash the benzene phase with water and then with saturated saline, and dry by adding colorless aqueous sodium sulfate. The solvent was removed and the residue was purified by silica gel chromatography (n-hexane:ether=322) to give 66 m green crystals of bithienylidene bisbenzoquinone.
g (100% yield) was obtained quantitatively.

The physical properties of the obtained compound were as follows.

1. Melting point 268℃ Green crystal 2. Electronic spectrum in CHsCNλmax nm (
log ) 263 (3,63), 428 (3,62),
620(4,15).

678 (4,50) 3, CV in C) ItClz, n-Bu
nNC104,0,1M vs 5CEEtred
= −〇, 41 V E+ox = +
0.91 V4, IR (KBr) 2950, 2910. 2860. 1632. 1
566, 13601326, 1110. 1022
．． 872,796.704 cm-'5,'H
-NMRin CDCl3 400 MH21
,36ppm(36H,s,t-Bu)7.25
(2)1. br, s, Benzene
e ring:)l-A)7.42 (2H,b
r, s, Benzene ring:) l-8
)7.43 (2H, m, Th1oph
ene ring)7.53 (2H, m,
Th1ophene ring)6, Mass
FD-MS m/z = 572 (M, 100%) Application
People Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1. The following general formula (1) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (1) [In formula (1), R^1, R^2, R^3, and R^4
are each independently a hydrogen atom or a straight chain having 1 to 8 carbon atoms,
Or display a branched alkyl group. Bithienylidene bisbenzoquinones shown in ]. 2. General formula (2) below ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (2) [In formula (2), R^1, R^2, R^3, and R^4 each independently represent a hydrogen atom , or a straight chain or branched alkyl group having 1 to 8 carbon atoms. ] The following general formula (1) is characterized by coupling two molecules of thienylphenols shown in the presence of an oxidizing agent ▲There are mathematical formulas, chemical formulas, tables, etc.▼(1) [Formula (1) Medium, R^1, R^2, R^3, and R^4
are R^1, R^2, R^3, and R^ in formula (2)
Display the same group as 4. ] A method for producing bithienylidene bisbenzoquinones.