JPS6215063B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to novel naphthalene derivatives that are valuable as dyes and pigments or intermediates thereof. Conventional vat dyes for textiles are of the type in which the dye is converted into a leuco form using a reducing agent in a bath, and the leuco form is oxidized in the air while the fiber is immersed in the bath, causing color development and adsorption onto the fiber. be. For example, indigo, which is a typical vat dye, has the structure of the following formula (), and for dyeing, fibers are immersed in a solution containing indigo, an alkali, and a reducing agent. Under the above conditions, indigo becomes a leuco substance of the following formula (), and it is thought that this substance undergoes air oxidation, develops color, and at the same time dyes fibers. However, these leuco bodies are extremely unstable and are immediately oxidized when exposed to air, so it is necessary to coexist a large amount of reducing agent in the bath, creating harsh conditions for fibers. . Furthermore, since the reduction was carried out under alkaline conditions, this caused further damage to the fibers. On the other hand, the sulfate ester of the leuco form of indigo is too stable and cannot be colored without using a strong oxidizing agent, such as potassium permanganate, which is also not a good condition for fibers. do not have. Moreover, the dyeing power of conventional vat dyes is not sufficiently satisfactory, and improvements in this aspect have been desired. In view of the above-mentioned circumstances, the present inventors have conducted intensive research to find out whether it is possible to obtain a leuco compound that has appropriate stability, that is, can be isolated as a leuco compound, and which develops a strong color when oxidized under mild conditions. The invention was completed. That is, the present invention is a naphthalene derivative represented by the following general formula (). The above naphthalene derivative is 2-butylamino-
5,8-Dihydroxynaphthoquinone is prepared in water, alcohol, a water-alcohol mixed solution in the presence of an alkali such as potassium hydroxide, sodium hydroxide or sodium carbonate using a reducing agent such as sodium dithionate, or in an aqueous hydrochloric acid solution in the presence of zinc. It can be obtained by reducing . Suitable reaction conditions include reaction under oxygen and anaerobic conditions at room temperature to reflux temperature for 1 to 5 hours. As mentioned above, the naphthalene derivative of the present invention is
It can be isolated as a leuco form from the reaction system, can be stored stably, and can be oxidized in a bath without using a special oxidizing agent to develop good color and dye fibers. With conventional vat dyes, sufficient dyeing cannot normally be expected unless the concentration is 5% or higher, but the naphthalene derivative of the present invention exhibits a dyeing power sufficient for practical use at a concentration of about 0.1%. The naphthalene derivative of the present invention can be used not only as a vat dye for textiles but also as a hair dye for human hair, and when used as a hair dye, it is particularly preferable to use it under mild conditions. Recognized as a characteristic. When dyeing using the naphthalene derivative of the present invention, the fibers can be dyed even better if 0.7 to 2.0% by weight of ammonia is present in the bath. Hereinafter, the present invention will be explained in more detail by giving examples of synthesis of the naphthalene derivative of the present invention. Synthesis Example 1 10 naphthazarin in 20 mmol of n-butylamine
An ethanol solution containing mmol was slowly added and stirred at a temperature of 0°C. After the reaction was completed, the reactant was poured into a dilute aqueous hydrochloric acid solution, and the precipitate was filtered and dried under reduced pressure.
This dried product was subjected to column chromatography using silica gel as a packing material and chloroform as a solvent to fractionate and purify the product to obtain 1.47 g of crystals.
(yield 55.8%). This product was confirmed to be 2-butylamino-5,8-dihydroxynaphthoquinone based on the following analytical values. Note that similar results can be obtained using benzene as a solvent for column chromatography. Mass spectrum M ⁺ = 261 Elemental analysis values C = 64.17 (calculated value 63.36) H = 5.78 (calculated value 5.79) N = 5.31 (calculated value 5.36) Nuclear magnetic resonance spectrum (CDCl ₃ , δ, ppm) ¹ H-NMR 13.58 (1H, OH, S), 11.97
(1H, OH, S), 7.03−7.30 (2H, arom.,
q), 6.15 (1H, NH, broad), 5.75 (1H,
quinone, s), 0.90-3.40 (9H, butyl
group) 0.902 g of 2-butylamino-5,8-dihydroxynaphthoquinone obtained above was dissolved in 60 c.c. of 50% aqueous ethanol together with 0.856 g of sodium carbonate and 3.457 g of sodium dithionate, and the mixture was heated under an argon atmosphere for 80 g. Stirred at ℃ for 3 hours. After the reaction is complete, the resulting crystals are washed with water and dried under reduced pressure to obtain the desired product.
0.477g (yield 52.4%) was obtained. The analytical value of this product is as follows, ¹³ C−
Since the chemical shift of the carbonyl group in NMR is observed on the lower magnetic field side than that of quinones,
It is thought that a methyl group or methylene group exists adjacent to the carbonyl group, and 6-butylamino-
It was confirmed to be 2,3-dihydro-5,8-dihydroxynaphthalene-1,4-dione. Mass spectrum M ⁺ = 263 Elemental analysis values C = 63.68 (calculated value 63.87) H = 6.54 (calculated value 6.51) N = 5.30 (calculated value 5.32) Nuclear magnetic resonance spectrum (CDCl ₃ , δ, ppm) ¹ H-NMR 12.95 (1H, OH, S), 12.50
(1H, OH, S), 6.21 (1H, aroma., S), 5.30
(1H, NH, broad), 2.74 (4H, −(CH ₂ ) ₂ −,
S), 0.90 to 3.40 (9H, butyl group) ¹³ C-NMR carbonyl group; 203.0, 196.9 Next, examples of staining using the naphthalene derivative of the present invention will be shown. Example 1 6-butylamino-2,3-dihydro-5,8
-dihydroxynaphthalene-1,4-dione 20mg
was dissolved in 20 g of water, and a wool muslin test fiber manufactured by Shirozome Co., Ltd. was immersed in the solution at a bath ratio of 1/40 and shake-dyed at a temperature of 30°C or 40°C to obtain a bright reddish-brown color. A wool muslin was obtained. In addition, at this time, if 0.7 to 2.0% by weight of ammonia is co-present, the dyeing will be performed even better. The obtained dyed fibers were washed in 200 c.c. of water at 30°C for 5 minutes, dried, and then processed using a Hitachi Color Analyzer.
Color was measured using Model 607. The results are shown in Table 1.

[Table] Example 2 6-butylamino-2,3-dihydro-5,8
-dihydroxynaphthalene-1,4-dione 20mg
Dissolved in 20g of water, soaked 1.0g of gray hair purchased from Abeille Co., Ltd. in the solution,
Shake staining for 45 minutes at a temperature of °C. after that,
The dyed hair was washed with 200 c.c. of water at 30°C for 5 minutes to obtain hair with no gray hair at all. The obtained dyed hair was washed using a commercially available shampoo and further treated using a rinse, but there was no change in color tone. Example 3 Test multi-fibers manufactured by Shirozome Co., Ltd. (acetate is beige, others are white) were dyed according to Example 1 to obtain bright reddish-brown dyed fibers depending on the presence or absence of ammonia and its amount. Ta.

Claims (1)

[Claims] 1. A naphthalene derivative represented by the following general formula ().