JPH0613479B2 - 5-amino-1H-pyrazole compound - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel 5-amino-1H-pyrazole compound. More specifically, it relates to a 5-amino-1H-pyrazole compound useful as an intermediate for a photographic coupler.

[Conventional technology]

1H-pyrazolo [3,2-C] -s-triazole compounds are compounds useful as photographic couplers, particularly magenta couplers. Examples thereof include British Patent 1,252,418, U.S. Patent 3,725,067, "Journal of the Chemical・
Society ”Perkin I (“ Journal of the Chemical
Its importance is described in Society “Parkin I), 2047-2052 (1977).

Regarding the production method of this compound, the above-mentioned patents and literatures, Research Disclosure V
ol 124, No 12443 (1974). The production method thereof can be represented by the reaction scheme shown below.

Reaction Scheme A (UK Patent 1,252,418, US Patent 3,725,067 "Journal of the Chemical Society" Perkin I
(“Journal of the Chemical Society” Parkin I) 2047
32052 (1977)) Reaction Scheme A Reaction Scheme B (Research Disclosure V
ol.124, No12443 (1977)) As is apparent from Reaction Schemes A and B, 5-hydrazino-1H-pyrazole-4-carboxylate can be used to synthesize previously known 1H-pyrazolo- [3,2-C] -s-triazoles. The ( 1 ) or 3-mercapto-4-amino-4H-1,2,4-triazole derivative ( 2 ) is used as an important intermediate. However, the 6-position substituent of 1H-pyrazolo [3,2-C] -s-triazole obtained by using these intermediates ( 1 ) and ( 2 ),
That is, R is extremely limited due to the restriction of the starting material,
When is a group other than an alkyl group, an aryl group, or a heterocycle, the yield of 1H-pyrazolo [3,2-C] -s-triazole is very low or cannot be obtained at all.

On the other hand, 1H-pyrazolo [1,5-b] -1,2,4-triazole compounds, which are isomers of 1H-pyrazolo [3,2-C] -s-triazole, are also used as photographic magenta couplers. Usefulness is described, for example, in JP-A-59-171956. Regarding its synthetic method, see JP-A-59-1.
71956 and JP-A-60-172982, and can be represented by the reaction scheme shown below.

Reaction scheme C C- (R represents alkyl, substituted alkyl, phenyl, substituted phenyl, and R'represents an alkyl group.) C- (R and R'represent an alkyl group, a substituted alkyl group, a phenyl group, a substituted phenyl group, and Hal represents a halogen atom.) C- (R, R ', R ", and R have the same meanings.) As is clear from the scheme of C- ~, 1H-pyrazolo [1,5-b] -1 obtained by using these synthetic methods. ,
Substituent in 6-position of 2,4-triazole compound, that is, R
Are limited, and in the above schemes C- to R, R is limited to an alkyl group, a substituted alkyl group, an aryl group, and a substituted aryl group.

Of 1H-pyrazolo [3,2-C] -s-triazole compounds and 1H-pyrazolo [1,5-b] -1,2,4-triazole compounds and a magenta dye formed by reaction with a color developing agent The light resistance, the absorption wavelength, the rate of dye formation, and the like are strongly influenced by the substituent R at the 6-position. Therefore, in order to obtain the magenta coupler having the optimum target performance, it was necessary to change the 6-position substituent in various ways.

Therefore, as shown in the general formula [I], 1H-pyrazolo [3,2-C] having a substituent at the 6-position via a thioether bond
-S-triazole compound and 1H-pyrazolo [1,
To obtain 5-b] -1,2,4-triazole compounds, it was necessary to develop a new synthetic intermediate.

[Object of the Invention]

An object of the present invention is to provide a novel 5-amino-1H-pyrazole compound, and more specifically, 1H-pyrazolo [3,2-C] -s-triazole compound and 1H-pyrazolo [1, 5-b] -1,2,4-triazole compound having a thioether bond at the 6-position as shown in the general formula [I], which is useful as an intermediate for a photographic coupler.
An object is to provide an amino-1H-pyrazole compound.

[Configuration of the present invention]

The novel 5-amino-1H-pyrazole compound according to the present invention is represented by the following general formula [I].

General formula [I] In the formula, R ₁ is an alkyl group (including those having a substituent),
It represents a cycloalkyl group, an aryl group (including those having a substituent) or a heterocycle, and X represents a hydrogen atom, a halogen atom or a carboxy group.

This compound is a 1H-pyrazolo [3,2-C] -s-triazole type photographic coupler and 1H-pyrazolo [1,5
-B] -1,2,4-triazole compound is useful as a synthetic intermediate for a photographic coupler.

Hereinafter, the compound of the present invention will be described in more detail.

The alkyl group represented by R ₁ in the general formula [I] is an alkyl group having 1 to 30 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a t-butyl group, Examples thereof include a pentyl group, a hexyl group, a heptyl group, a benzyl group, an octyl group, a decyl group, a dodecyl group, a tetradecyl group, a hexadecyl group and an octadecyl group.

The cycloalkyl group represented by R ₁ is a 3- to 6-membered cycloalkyl group.

The aryl group represented by R ₁ is a phenyl group or a naphthyl group.

The heterocyclic group represented by R ₁ is a 5- or 6-membered heterocyclic group, for example, a thienyl group, a furyl group, a pyrrolyl group,
Examples thereof include thiazolyl group, pyridyl group, imidazolyl group, pyrrolidyl group, piperidyl group and morpholyl group.

An alkyl group represented by R ₁ , a cycloalkyl group,
The aryl group and heterocyclic group may further have a substituent.

Examples of the halogen atom represented by X in the general formula [I] include a chlorine atom, a bromine atom, an iodine atom and a fluorine atom, but a chlorine atom and a bromine atom are preferable, and a chlorine atom is more preferable.

The alkoxycarbonyl group represented by X above is
Examples thereof include a methoxycarbonyl group, an ethoxycarbonyl group, a propyloxycarbonyl group and a benzyloxycarbonyl group. Examples of the aryloxycarbonyl group represented by X include a phenoxycarbonyl group.

The general formula [I] may form a salt with a protic acid (however, this is not an important constituent of the present invention). Typical protic acids include hydrochloric acid, hydrobromic acid, sulfuric acid, acetic acid, methanesulfonic acid, pyromeritic acid and the like.

Next, a method for synthesizing the 5-amino-1H-pyrazole compound according to the present invention will be described.

Scheme D R. Gompper, W. Tpfl, Hemische Berichte (Chem.Be
r.), 95 , 2811 (1962).

Scheme E However, Halo represents Cl, Br, F, and the compounds ( 1 ), ( 2 ), and ( 3 ) represent the compounds of the present invention.

The 5-amino-1H-pyrazole compound thus obtained is a 1H-pyrazolo [3,2-C] -s-triazole compound and 1H useful as a photographic coupler as shown in the following scheme. -Pyrazolo [1,5-b]-
It can lead to 1,2,4-triazole compounds.

Scheme F That is, a 5-amino-1H-pyrazole compound is diazotized by a commonly used method and then reduced with a reducing agent such as stannous chloride or sodium sulfite to give a 5-hydrazino-1H-pyrazole compound. After being compounded and further acylated, a chlorinating agent such as phosphorus oxychloride or thionyl chloride is used to close the ring in the presence of a base,
1H-Pyrazolo- [3,2 having a substituent through the thioether bond at the 6-position, which is useful as a magenta coupler for photography
A -C] -s-triazole-based compound can be synthesized.

Further, by applying the methods of scheme C- and scheme C-, a photograph of a 1H-pyrazolo [1,5-b] -1,2,4-triazole system having a substituent at the 6-position through a thioether bond is shown. Magenta coupler (R is R ₁ S-) can be used.

In Scheme F, R ₁ and X are the same as those described in general formula [I].

Next, specific examples of the compound of the present invention are shown below, but the present invention is not limited thereto.

Compound Example 1 Two Three Four 5 6 7 8 9 Ten 11 12 13 14 15 16 17 18 19 20 twenty one The photographic couplers derived from the compounds of the present invention are shown below, but the present invention is not limited thereto.

II-1 II-2 II-3 II-4 II-5 II-6 II-7 II-8 II-9 II-10 [Examples] Hereinafter, the synthesis of the compound of the present invention and the synthesis of a photographic coupler derived from the compound of the present invention will be described with reference to specific examples. Of course, the present invention is not limited to the following examples.

Synthesis Example-1 (Synthesis of Exemplified Compound 1) (i) 100 g of methyl 2,2-bismethylmercapto-1-cyanoacrylate (R. Gompper, W. Tpfl, Hemische Berichte (Chem. Ber.), 95 , 2861 (1962)) and 25 g of 100% hydrazine hydrate are added to 600 ml of ethanol and heated under reflux for 1 hour. After completion of the reaction, the solvent was distilled off under reduced pressure, and the residue was recrystallized from methanol to obtain 66.2 g of methyl = 5-amino-3-methylthio-4-pyrazolecarboxylate.

(ii) Methyl = 5-amino-3-methylthio-4-pyrazolecarboxylate (20 g) is added to a 4N sodium hydroxide aqueous solution, and the mixture is heated under reflux for 1 hour. Dilute hydrochloric acid is added dropwise to adjust the pH to 5, and then cooled. The precipitated crystals are separated by filtration and recrystallized from ethanol to obtain 5-amino-3-methylthio-4-pyrazolecarboxylic acid (12.5 g).

Elemental analysis value, C ₅ H ₇ O ₂ S, FD MS: M ⁺ 173 (parent peak) Synthesis Example-2 (Synthesis of Exemplified Compound 2) 10 g of 5-amino-3-methylthio-4-pyrazolecarboxylic acid is added to 50 ml of xylene and heated under reflux for 30 minutes. After distilling off the solvent under reduced pressure, the residue was recrystallized from hexane,
6.2 g of 5-amino-3-methylthiopyrazole are obtained.

Elemental analysis value, C ₄ H ₇ N ₃ S, FD MS: M ⁺ 129 (parent peak) Synthesis Example-3 (Synthesis of Exemplified Compound 3) 4.5 g of 5-amino-3-methylthiopyrazole was dissolved in 30 ml of chloroform, and 4.7 g of N-chlorosuccinimide was added little by little. . After stirring for 30 minutes at room temperature, the solvent is distilled off under reduced pressure, ethyl acetate and water are added to the residue, and the organic layer is separated. Further, the solvent was distilled off under reduced pressure, the residue was recrystallized from a mixed solvent of hexane and ethanol, and 3.9 g of 5-
Amino-4-chloro-3-methylthiopyrazole is obtained.

Elemental analysis value, C ₄ H ₆ N ₃ SCl, FD MS: M ⁺ 163 (parent peak) Synthesis Example-4 (Synthesis of Exemplified Compound 7) (i) 50 g of methyl 2,2-bismethylmercapto-1-cyanoacrylate and 32.5 g of sodium thiophenolate were added. 30
Add to 0 ml of toluene and heat to reflux for 8 hours. The precipitated solid is filtered off and the filtrate is concentrated. Ethanol 50 in the residue
Add 0 ml and 12.3 g of 100% hydrazine hydrate and heat to reflux for 2 hours. After completion of the reaction, the solvent was distilled off under reduced pressure, and the residue was recrystallized from methanol to obtain 25 g of methyl 5-amino-3-phenylthio-4-pyrazolecarboxylate.

(ii) 24.0 g of methyl = 5-amino-3-phenylthio-4-
Pyrazole carboxylate 4N sodium hydroxide 30
Add 0 ml and heat to reflux for 2 hours. After cooling, add hydrochloric acid to pH
Set to around 5. 18.2 g of 5-amino-3-phenylthio-4-pyrazolecarboxylic acid are obtained. Decomposes above 120 ° C.

Elemental analysis value, C ₁₀ H ₉ N ₃ O ₂ S, FD MS: M ⁺ 235 (parent peak) Synthesis Example-5 (Synthesis of Exemplified Compound 8) 180 g of 5-amino-3-phenylthio-4-pyrazolecarboxylic acid is heated at 140 to 150 ° C for 20 minutes. After the vigorous firing has ended, it is cooled and 9.5 g of 5-amino-3-phenylthiopyrazole are obtained.

Elemental analysis value, C ₉ H ₉ N ₃ S, FD MS: M ⁺ 191 (parent peak) Synthesis Examples-6 to 21 (Synthesis of Exemplified Compounds 4 to 6 and 9 to 21) Exemplified Compounds 4 to 6 and 6 using the same method as in the above Synthesis Example.
9 to 21 are synthesized.

The obtained product was confirmed to be each exemplified compound by analysis. The results of elemental analysis are summarized in Table 1.

Synthesis Example-22 (Synthesis of Exemplified Compound II-1) A synthesis example of a photographic coupler derived from the compound of the present invention is shown below.

(i) 8.2 g of 5-amino-4-chloro-3-methylthiopyrazole (Exemplified Compound 3) was added to 100 ml of 6N hydrochloric acid, and 0
Cool to ° C. To this, add 3.8 g of sodium sulfite to 10 m of water.
Add the solution dissolved in l dropwise. After stirring for 30 minutes at 0 ° C., a solution of 24 g of stannous oxide in 70 g of concentrated hydrochloric acid is slowly added. After stirring at 0 ° C. for 30 minutes, the mixture is stirred at room temperature for 1 hour. Then add 400 ml of water and pass through hydrogen sulfide gas. The precipitated tin salt was filtered off and the filtrate was concentrated to give 5-hydrazino-4-chloro-3-methylthiopyrazole hydrochloride.
9.5 g are obtained.

(ii) 5.4 g of 5-hydrazino-4-chloro-3-methylthiopyrazole hydrochloride and 6.9 g of palmitic acid chloride are added to 100 ml of ethyl acetate, and 5.5 g of triethylamine is added at room temperature. After stirring for 30 minutes, the precipitated crystals are filtered off and washed with water. The remaining crystals were recrystallized from acetonitrile to give 8.3 g of 4-chloro-3-methylthio-5- (2
Obtain palmitoylhydrazino) pyrazole.

(iii) 4-chloro-3-methylthio-5- (2-palmitoylhydrazino) pyrazolepi 8.0 g and phosphorus oxychloride 3.0 g
And are added to 200 ml of toluene and heated under reflux for 1.5 hours. The solution is evaporated under reduced pressure, pyridine (4.5 g) and acetonitrile (200 ml) are added to the residue, and the mixture is heated under reflux for 1.5 hours. After the reaction is completed, the product is decanted under heat to remove the tar content and then cooled. The precipitated crystals are recrystallized from acetonitrile to obtain 5.8 g of the desired product (II-1).

Elemental analysis value, as C ₂₀ H ₃₅ N ₄ SCl, FD MS: M ⁺ 398 (parent peak) [Effect of the invention] As described above, according to the present invention, novel 5-amino-1H-
A pyrazole-based compound can be provided, which is useful as an intermediate for a 1H-pyrazolo [3,2-C] -s-triazole-based photographic coupler.

Claims (1)

[Claims] 1. A 5-amino-represented by the following general formula [I]:
1H-pyrazole compound. General formula [I] In the formula, R ₁ is an alkyl group (including those having a substituent),
It represents a cycloalkyl group, an aryl group (including those having a substituent) or a heterocycle, and X represents a hydrogen atom, a halogen atom or a carboxy group.