JPS61283663A - Thioindigo and production thereof - Google Patents

Abstract

PURPOSE:To obtain thioindigo which exhibits photochromism, can form a monomolecular film and is suitable for use as an information recording material, by synthesizing thioindigo through a thiol by starting with a 12-25C long-chain alkylbenzene. CONSTITUTION:A 12-25C long-chain alkylbenzene is used as a starting material to synthesize a thiol therefrom by sulfonation, etc., and an indoxyl group is formed through a thioglycolic acid therefrom to produce a thioindigo of formula I or II (wherein R1, R2 are each a 12-15C alkyl). In the resulting thioindigo, a 12-25C long-chain alkyl group in the dye skeleton has hydrophobicity and the dye skeleton moiety acts as a hydrophilic group. Thus, a good monomolecular film can be formed at the interface between gas and liquid by an amphipathic action. An ultrathin film can be prepd. by Langmuir's project method.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a novel thioindigo used as a photochromic substance in information storage materials, etc., and a method for producing the same.

Conventional technology Thioindigos have the property of being able to undergo reversible cis-trans 5゛1Σ conversion accompanied by a color change upon irradiation with light (
photochromism). recent years,
Attempts have been made to use the color change of photochromic materials for information storage, and as a promising means, ultra-thin films are being researched using the Langmuir-Proscienoto (LB) method.

Problems to be Solved by the Invention In producing an LB film, the dye used must form a monomolecular film, but it is important to note that conventional commercially available or developed thioindigo cannot form a monomolecular film.

In other words, the conventionally developed thioindigo does not have a sufficient balance between hydrophobic and hydrophilic groups, and does not form a good monomolecular film even when the dye is spread on the air-water interface. Means for solving the problem that it was not possible to produce the thioindigo of the present invention is represented by the general formula (wherein R1-R5 represent an alkyl group having 12 to 15 carbon atoms).

As for its production method, thioindigo is produced using a long-chain alkylbenzene having 12 to 260 carbon atoms as a starting material via thiol.

Effect The long-chain alkyl group from carbon 12 to 260 in the pigment skeleton of thioindigo has hydrophobicity, and the pigment skeleton plays a role as a hydrophilic group. Due to its amphipathic properties, the thioindigo of the present invention is favorable at the air-water interface. forms a monolayer.

Regarding the production method, thioindigo compounds are very difficult to dissolve in organic solvents, and the reaction of introducing substituents after forming a thioindigo skeleton is accompanied by many difficulties. Therefore, it is advantageous to form a thioindigo skeleton by reacting a material into which a long-chain alkyl group has been introduced as a raw material.

Long-chain alkylbenzenes can be prepared by sulfonation or other means.
Thiol is obtained, and thioindigo can be produced by forming an indoquine/l/ group via thioglycolic acid.

Examples The compounds shown in general formulas (1) and (2) are synthesized from commercially available long-chain alkylbenzenes by the following reaction route.

The details of the present invention will be explained below with reference to specific examples.

Example 1 O Step 1: 60°C in which n-octadecylbenzene 3'30y and 16og of sulfuric acid were heated at 126°C for 3 hours.
After cooling to
occurred. After adding sodium chloride to obtain a sodium salt, the mixture was extracted several times with ether to obtain 340 g of sodium p-octadecylbenzenesulfonate (4).

Step 2: 300 g of sodium p-octadecylbenzenesulfonate (4) was suspended in dry DMF, and thionichloride/L/120.9 was added dropwise, followed by stirring at room temperature for about 1 hour. The reaction mixture was poured into ice water containing dissolved sodium chloride, and the resulting precipitate was filtered and washed with water to obtain 280 g of p-octadecylbenzenesulfonyl chlorophyte.

Step 3: p-octadecylbenzenesulfonyl chloride (s)so, 9. 42.9 g of zinc powder was added little by little to a mixture of 250 g of ice and 84 I of concentrated saccharic acid at 0° C. while stirring. After all the additions were completed, the mixture was kept at 2°C for 1.5 hours, then returned to room temperature, and heated and stirred at +00°C for 8 hours. The reduced product was extracted with a sieve and chiller, washed with water, and dried under reduced pressure, and p-octadecylthiophenol (6) was extracted at 261 m.

Step 4: p-octadecylthiophenol (6)
Dissolve 10 g in 33% NaOH aqueous solution 1ooCC,
6 g of monochloroacetic acid neutralized with Ha2Go was added, and the mixture was heated and stirred at 90°C for 1 hour.

p-ophtade by acidifying with hydrochloric acid after the reaction,
Silphenylthioglycolic acid 5.9 (7) was obtained.

Step 6: pCj7.
1. Add e 9 and heat at 70°C for 2 hours. After cooling,
After adding ol, 2.1, and p and further heating at 60'C for 1 hour, hydrolysis was performed and benzene was added.
9 The organic layers were collected, washed with water, and purified using a silica gel column to obtain 3 g of white crystals of 6-octadecylthioindoxyl (8).

Step 6: Commercially available phenylthiol is reacted in a sinusoidal manner with Step 4 and Step 6 to give thioindoxyl, which is reacted with p-nitrododimethylaniline to obtain thionaphthenequinone-2-(4'-dimethylamino ) anil (
9) was synthesized. 5-octadecylthioindoxyl (
8) 1 g and 0.669 of thionaphthenequinone-2(41-dimethylamino)anyl (9) were mixed with chlorhenzene 20I
! Dissolve in Ie, add a few drops of piperidine and heat to 115°C ~ 1
The mixture was heated and stirred at 18°C for 2 hours to obtain 0.7 g of the desired 6-ophtadecylthioindigo (3). Melting point is 144°
It was C.

Example 2 Production of n-octadecylbenzene (10) Steps 1 to 1 of Example 1
5-octadecylthioindoxyl β)
I got it.

Step completed: 5-octadecylthioindoquine (8)
Add 1 g to a water-alcohol solution and prepare K and F.

3g of (ON)6 was added and stirred at room temperature to react. Extraction with benzene gave 100 m and p of red crystals of the target product, 5.5'-dioctadecylthioindigo (10).

The melting point was 162°C.

Example 3 Step 1 of Example 1 from n-octadecylbenzene
5-octadecylthioindoxyl (8
) was obtained.

Further, 5-hexadecylthioindoquine/1z (12) was obtained from n-hexadecylbenzene in the same manner as Steps 1 to 5 of Example 1. This was reacted with p-nitrosodimethylaniline to synthesize 6-hexadicylthionaphthenequinone-2-(4'-dimethylamino)anyl (12).

Step 8: 6-octadecylthioindochini/I/1
g and 5-hexadecylthionaphthenequinone-2-(4'
-dimethylamino)ani/L/(12) 1g to 25mj of chlorobenzene? Dissolve it in water, add a few drops of piperidine, and add 12
Heat and stir at 0°C for 2 hours to obtain the desired 5-octadenyl, 5'-hexadecylthioindigo (11).
I was able to get it.

All of the thioindigo shown in Examples 1 to 3 showed photochromism. In addition, a good monomolecular film was formed at the air-water interface.

Effects of the Invention The thioindigo of the present invention has photochromism and can form a good monomolecular film to produce an LB film. It is highly practical as an information storage material.

Name of agent: Patent attorney Toshi Nakao, 1 bottle

Claims (2)

[Claims] (1) Thioindigo represented by the general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, R_1 to R_3 represent an alkyl group having 12 to 25 carbon atoms). (2) Thioindigo represented by the general formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R_1 to R_3 represent an alkyl group having 12 to 25 carbon atoms) Carbon number 12-2
A method for producing thioindigo using the long-chain alkylbenzene of No. 5 as a starting material and synthesizing it via thiol.