JPS5851967B2 - Novel aminothiofluorane-γ-tractam dye and its production method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to novel aminothiofluorane-gamma-lactam dyes and processes for their preparation.

More specifically, the present invention relates to the general formula (wherein R and R may be the same or different, each represents a lower alkyl group having 1 to 4 carbon atoms, and R1
represents a hydrogen atom, a lower alkyl group having 1 to 3 carbon atoms, a cyclohexyl group, or a phenyl group that may have a substituent, and n = O or 1). A dye, and in synthesizing the dye, an aminothiofluorane compound represented by the general formula (wherein R and R' are the same as defined above) or an acid addition salt thereof, and ammonia, a primary amine, or hydrazine. The present invention relates to a method for producing a novel aminothiofluorane-γ-lactam dye represented by the general formula (1), which involves reacting the dye with a derivative.

Color-forming recording methods such as pressure-sensitive copying paper and heat-sensitive recording paper that use colorless electron-donating coloring agents have already become widely known as a result of streamlining office work, and various color-forming compounds are known.

At present, fluoran-based and fluoran-gamma-lactam-based coloring agents are known as colorless coloring agents that produce a red color, and the latter fluoranic compounds with a lactam ring, i.e., rhodamine lactam compounds, have been put into practical use as coloring agents for some time. Although there are many reports in the literature, there have been no literature publications regarding the aminothiofluorane-γ-lactam dye represented by the general formula (I) according to the present invention.

As a result of various studies, the present inventors have previously provided a novel asymmetric aminothiofluorane-based coloring agent. completed.

General formula (II) which is a raw material for the aminothiofluorane-γ-lactum dye represented by general formula (I) according to the present invention
The aminothiofluorane compound shown by is, like the rhodamine B derivative, the substance itself is unstable and colored reddish, and has many drawbacks as a pressure-sensitive coloring agent such as color development over time when left alone. It has been found that the dye represented by formula (I) is extremely useful as it is stable in the atmosphere and meets the requirements as a coloring agent for pressure-sensitive copying paper, heat-sensitive recording paper, photosensitive paper, etc. .

That is, the aminothiofluorane-γ-lactam dye represented by the above general formula (I) is itself an almost colorless or light-colored powder, dissolves in a wide variety of organic solvents, and can be used in powder or solution state. When brought into contact with or melted together with an electron-accepting substance such as an inorganic solid acid, an organic acid, or an organic acid polymer, it develops a reddish-purple color.

It is also possible to adjust the color tone as desired by combining it with other known color formers.

The hue developed by the aminothiofluorane-γ-lactam dye represented by the general formula (1) according to the present invention is such that the dye has an absorption maximum in the 570 to 580 mμ region, and furthermore, the dye has an absorption maximum in the 570 to 580 mμ region, and
It has a slight absorption at 540 mμ, and its absorption wavelength is shifted to the longer wavelength side than that of rhodamine-based and fluoran-γ-lactam-based compounds, so it exhibits a dark red color with a purplish tinge. It emits strong fluorescence in fatty acid solutions such as propionic acid.

Aminothiofluorane γ- represented by the general formula (I)
Lactam dyes are synthesized by the following method.

The 3,6-bis-substituted aminofluorane derivative represented by the general formula (n) can be obtained in high yield by either of the following methods a) and b).

Namely, a) an m-disubstituted aminothiophenol derivative and phthalic anhydride are mixed in a molar ratio of 2:1 in the presence of a Friedel-Craft catalyst such as aluminum chloride or stannic chloride, or in the absence of a catalyst, carbon dioxide or tetrachloroethane. , nitrobenzene, benzene, chlorobenzene or the like, by reflux or melt reaction with or without a suitable solvent, but preferably a solvent-free melt reaction in the presence of the above catalyst is suitable.

and b) m-substituted aminothiophenol derivatives and o-(
It is obtained by reacting a 4-monosubstituted amino-2-hydroxybenzoyl)benzoic acid derivative in the presence of a condensing agent.

For example, this can be achieved using a condensing agent such as sulfuric acid, oleum, polyphosphoric acid, phosphoric anhydride, acetic anhydride, acetic acid, phosphorus pentoxide, or phosphorus oxychloride, or in the presence of the Friedelkraff catalyst. Preferably, it is obtained by a heating reaction in an acetic anhydride solvent in the presence of the above catalyst.

By heating and refluxing the thus obtained 3,6-bis-substituted aminothiofluorane derivative represented by formula (n) and an equivalent or more amount of ammonia, primary amine or hydrazine derivative in an organic solvent or without a solvent. The general formula (I
) is synthesized.

Examples of the acid addition salt of the 3,6-bis-substituted aminothiofluorane-γ-lactam compound represented by the general formula (n) include hydrochloride, sulfate, and perchlorate.

For example, the following are suitable as typical primary amine or hydrazine compounds used in the present invention.

Methylamine, ethylamine, propylamine, cyclohexylamine, aniline, toluidine, chloraniline, nitroaniline, benzylaniline, naphthylamine, aminopyridine, aminoquinoline, methylhydrazine, ethylhydrazine, phenylhydrazine,
These include tolylhydrazine, nitrophenylhydrazine, naphthylhydrazine, and the like.

Therefore, depending on the type of amine and hydrazine compound to be reacted, the group forming a lactam bond in general formula (I) has the formula>N (NH) n Rt (where R1 is a hydrogen atom, or a lower alkyl group having 1 to 3 carbon atoms). a cyclohexyl group, a phenyl group or a naphthyl group which may have a substituent, and this substituent can be represented by a nitro group, )\logen atom, a lower alkyl group, and n20 or 1 can.

The method for synthesizing the dye represented by the general formula (I) will be explained in detail below using production examples, but the present invention is not limited to these production examples.

Production Example (1) 100 liters of ethanol in which 8 g of 3,6-bis-diethylamino-thiofluoran perchlorate obtained by the above method a) or b) expressed by general formula (II) and 8 g of ammonia were dissolved was dissolved. The mixture was placed in a 200rrLl autoclave and reacted at 150°C for 2 hours.

After cooling, the precipitated crystals were separated in a furnace and recrystallized from benzene-methanol to obtain colorless tetraethyl-N(hydro)thiorhodamine lactam with a melting point of 247.5-249.0°C.
3,6-bis-diethylamino-thiofluorane-γ-
34.5 g of imidolactam was obtained.

Elemental analysis: C26H31N30S C@H (d N ring 5(2) actual value 72
,00 7.25 9.67 7.34 Calculated value 72.
06 7.16 9,70 7.3995% λmax in acetic acid solution; 576.535mlt.

(2) 5 g of 3,6-bis-diethylamino-thiofluorane hydrochloride represented by general formula (U) and 8 g of cyclohexylamine were heated under reflux for 7 hours.

The reaction solution was poured into 700 ml of water, and the precipitate was separated in a suction furnace, washed with methanol, and recrystallized from benzene to give colorless tetraethyl-N(cyclohexyl)thiorhodamine lactam (3,6-bisdiethylamino- Thiofluorane-γ-cyclohexylimidolakucum)2.
1.9 was obtained.

Melting point: 135.0-137.0°C.

Elemental analysis: C3□H4oN30S C@H■Nsuke 8-wheel measured value 75.79 7-48 7.76 5.95 Calculated value 75.70 7.61 7.79 5.9495
λmax in acetic acid solution; 577.535 mμ.

(3) Except for using phenylhydrazine (2)
After the same reaction and post-treatment as above, colorless tetraethyl-N(phenylhydrazyl)thiorhodamine lactam [3゜6-
Bis-diethylamino-thiofluorane-γ-phenylhydrazidolactam] was obtained.

Melting point: 186.0-187.5°C.

Elemental analysis: C3□H36N40S C□□□ H (to) N (to) 8-wheel actual measurement value
74.40 6.56 10.14 5.98 Calculated value
74.45 6.57 10.22 5.8495 λmax in acetic acid solution; 579.535 mμ.

General formula (If) used as a raw material in the above production example
Examples of the production of the 3,6-bis-substituted aminofluorane derivative represented by the above methods a) and b) are shown below.

a) M, S, Newman, H, A, Karne
s(J, Org, Chem.

N obtained according to the method of 31.3980 (1966)),
N-diethylamino-m-thiophenol (bp, 10
10 g of fucuric anhydride (3-105° C.70,2 Hg) and 4.1 g of fucuric anhydride were melted at 140° C., 8.2 g of aluminum chloride was added little by little with stirring, and the mixture was reacted for 1.5 hours.

Cool to room temperature, add 700ml of ice water, and add carbonated water.
Neutralized with aluminum, extracted with chloroform, distilled off the solvent, recrystallized from methanol-benzene, and obtained a melting point of 134.
3,6-bis-diethylamino-thiofluorane at ˜136° C. was obtained.

Also contains 12.5g of shiny red-green crystals as perchlorate.
(yield: 81).

Perchlorate decomposes at 250°C.

Elemental analysis: C28H3□ClN206S C□ H (To) N@5 (4) Actual value 60,22 5.53 4,83 5.62 Calculated value 60.16 5,55 5,01 5.7395
λ in acetic acid solution: 576.535 mμ0aX b) N,N-diethylamino-m-thiophenol 10
17.39 g, o-(4-diethylamino-2-hydroxybenzoyl)benzoic acid in 40 TLl of acetic anhydride.
After melting at 0° C. and adding 8.3 g of zinc chloride, the mixture was heated under reflux for 1 hour.

After adding the reaction solution to ice water, the post-treatment was carried out in the same manner as in a) above to obtain 24.0 g (78%) of the same perchlorate of 3,6-bis-diethylamino-thiofluorane.

Aminothiofluorane represented by the above general formula (1)
To prepare the pressure-sensitive copying paper according to the present invention using a γ-lactam dye, except for using the dye as a coloring agent, as is well known in the art, for example, the method described in U.S. Pat. No. 2,548,366 The oil-containing microcapsules and the method for producing the same described in Japanese Patent No. 2800457 and the like are employed.

Furthermore, the aminothiofluorane-γ-lactam dye according to the present invention can be used alone or in combination with a known coloring agent for color recording.

Next, a pressure-sensitive copying paper using a typical aminothiofluorane-γ-lactum dye represented by the general formula (I) as a coloring agent will be shown as an application example.

Application Example 1 2.5 g of the color former shown in Production Example (2) was dissolved in 100 g of diisopropylnaphthalene (KMC-133, Military Chemical), and 20 g of gum arabic and 160.9 g of water were added at 50°C and emulsified. .

20 g of acid-treated gelatin and 160 g of water were added to this emulsion, and acetic acid was added with stirring to adjust the pH to 5.

Next, 500g of water is added to advance coacervation to form a thick gelatin-gum arabic liquid film around the diisopropylnaphthalene oil droplets in which the color former is dissolved, and then acetic acid is added to adjust the pH. 4.4 and 37
After curing the liquid film by adding 38 g of a formalin aqueous solution, it was cooled to 1.0°C, a sulfur hydroxide aqueous solution was added to adjust the pH to 9, and the mixture was left for 5 to 6 hours to complete the encapsulation. progressed to.

This capsule liquid was applied to paper by a coating method such as roll coating or air knife coating and dried.

This coated paper (upper paper) is brought into close contact with paper (lower paper) coated with an acidic electron-accepting adsorbent such as acid clay or phenol-formalin resin, and pressure is applied using a pencil or typewriter key. When added, clear dark reddish-purple letters appeared on the bottom page of the paper in that area.

The light resistance and water resistance of this dark reddish-purple coloring agent were sufficient for practical use and showed extremely excellent stability over time.

Application example 2 Color former 1.1 shown in production example (3), crystal violet lactone o, sg, benzoyl leucomethylene blue 〇,! 11.3.6-Dinithoxyfluorane 1.2
The pressure-sensitive copying paper obtained by processing in the same manner as in Application Example 1 except that G was mixed and used as a coloring agent developed a vivid black color when pressure-sensitive writing was performed.

This color development showed extremely excellent stability over time.

In addition, thermosensitive recording paper was prepared by a conventional method using the novel aminothiofluorane-γ-lactam dye of the present invention, for example, the lactam dye obtained in Production Example (1), (2), or (3). Color development by infrared irradiation and thermal printing of thermosensitive recording paper showed extremely satisfactory results.

Claims (1)

[Scope of Claims] 1 (In the formula, R and R' may be the same or different and each represents a lower alkyl group having 1 to 4 carbon atoms, and R
1 represents a hydrogen atom, a lower alkyl group having 1 to 3 carbon atoms, a cyclohexyl group, or a phenyl group that may have a substituent, and n = O or 1). Rakukum dye. 2. An aminothiofluorane compound represented by the general formula (wherein R and R' may be the same or different and each represents a lower alkyl group having 1 to 4 carbon atoms) or an acid addition salt thereof and ammonia, It is characterized by reacting a primary amine or a hydrazine derivative (wherein R and R
' may be the same or different and each represents a lower alkyl group having 1 to 4 carbon atoms, and R1 may have a hydrogen atom, a lower alkyl group having 1 to 3 carbon atoms, a cyclohexyl group, or a substituent. Indicates a phenyl group, n =
A method for producing a novel aminothiofluorane-γ-lactum dye represented by: O or 1).