JP2002338548A - Method for producing 3-amino-4-substituted-5-pyrazolones - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a 3-amino-4-substituted-5-pyrazolone providing preferable photographic performances, with which a benzoyl group of a 4-substituted-5-pyrazolone containing a benzoylamino group, which may contain a substituent group, at the 3-position is efficiently deprotected, productivity is high and a mass production can be carried out. SOLUTION: This method for producing a 3-amino-4-substituted-5-pyrazolone is characterized in that the method comprises a process for subjecting the benzoylamino group of the 4-substituted-5-pyrazolone containing a benzoylamino group, which may contain a substituent group, at the 3-position to an alkali hydrolysis.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a process for producing 3-amino-4-substituted-5-pyrazolones useful as, for example, coupler intermediates for photographic light-sensitive materials and color marking material intermediates.

[0002]

2. Description of the Related Art A magenta color image forming 2-equivalent coupler which is a homopolymer or a copolymer having a repeating unit derived from an ethylenically unsaturated monomer having a pyrazolone residue is a magenta coupler for subtractive color photography. It is particularly useful as This is disclosed in U.S. Pat. No. 4,367,282 (corresponding to JP-A-58-224352).

The ethylenically unsaturated monomer having a pyrazolone residue that provides a repeating unit of the polymer coupler is a group capable of leaving at the 4-position by a coupling reaction with an oxidized developing agent (hereinafter referred to as “coupling-off”). ), And a step of introducing 3-amino-4-substituted-
It can be synthesized by bonding a residue having an ethylenically unsaturated group to the 3-position amino group of 5-pyrazolones. Here, the intermediate 3-amino-4-substituted-
5-Pyrazolones have conventionally been obtained by protecting a 3-position amino group with an acetyl group using a 3-amino-5-pyrazolone compound (A) as a starting material, as shown in Scheme 1 below.
It was obtained by introducing a leaving group in the substitution step, followed by deprotection of the acetyl group, leading to the 4-halogen (C).

Scheme 1

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The key reaction step in this method is a substitution step for deriving compound (D) from compound (C). However, this process has problems that the yield is very low and that there are many by-products. To solve this problem, it has been reported that the use of a benzoyl group as the protecting group for the 3-position amino group can greatly improve the yield of the substitution step.
(See Japanese Patent Application Laid-Open No. 62-70363.) Here, acid hydrolysis is used as a means for deprotecting the benzoyl group.

However, deprotection of a benzoyl group by acid hydrolysis requires a longer time at a higher temperature than deprotection of an acetyl group, and a photograph of a photographic material prepared using a polymer coupler synthesized from a compound synthesized by this method is required. There is a problem that the properties deteriorate.

[0007]

An object of the present invention is to efficiently deprotect the benzoyl group of 4-substituted-5-pyrazolones having a benzoylamino group which may have a substituent at the 3-position. Another object of the present invention is to provide a method for producing 3-amino-4-substituted-5-pyrazolones which has high productivity, can be mass-produced, and gives favorable photographic properties.

[0008]

[Means for Solving the Problems] As a result of intensive studies,
The object of the present invention has been achieved by the following (1) to (4).

(1) A method of 4-substituted-5-pyrazolones having a benzoylamino group which may have a substituent at the 3-position, comprising a step of subjecting the benzoylamino group to alkaline hydrolysis. A method for producing -amino-4-substituted-5-pyrazolones.

(2) The 4-substituted-5-pyrazolones having an optionally substituted benzoylamino group at the 3-position are represented by the following general formula (I): )).

[0011]

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In the formula, L is a thiocyano group, an aryloxy group, an alkoxy group, an alkylthio group, an arylthio group,
Represents a heterocyclic thio group, an imide group, an imidazolyl group, a pyrazolyl group, or a triazolyl group. R ¹ represents an unsubstituted or substituted alkyl group or an unsubstituted or substituted aryl group, R ² represents a substituent on a benzene ring, and n represents an integer of 0 to 5. When n is 2 or more, a plurality of R ² may be the same or different.

(3) The method according to (1) or (2), wherein the alkaline hydrolysis is performed in the presence of a barium compound.

(4) The method according to (1) or (2), wherein the alkaline hydrolysis is performed in the presence of a lithium compound.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The production method of the present invention will be described below in detail. The production method of the present invention provides a 4-substituted-5 having a benzoylamino group optionally having a substituent at the 3-position.
-Alkaline hydrolysis of the benzoylamino group of pyrazolones.

In the present invention, the 4-substituted-5-pyrazolones having an optionally substituted benzoylamino group at the 3-position have a benzoyl group at the 3-position as a protective group. And the following general formula (I)
Is preferably represented by

[0017]

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In the formula, L represents a coupling-off group. R
¹ represents an unsubstituted or substituted alkyl group or an unsubstituted or substituted aryl group,, R ² represents a substituent group on the benzene ring, n is an integer of 0-5. When n is 2 or more, a plurality of R ² may be the same or different.

The general formula (I) can also be shown as a tautomer as shown below.

[0020]

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R ¹ is an unsubstituted or substituted alkyl group or an unsubstituted or substituted aryl group. The alkyl group preferably has 1 to 15 carbon atoms and may be linear, branched or cyclic. The aryl group is preferably a phenyl group or a naphthyl group, particularly preferably a phenyl group. Examples of the substituent of each of the alkyl group and the aryl group include a halogen atom (for example, a fluorine atom and a chlorine atom), an alkyl group (for example, methyl and ethyl), an aryl group (for example, phenyl and naphthyl), a cyano group, a carboxyl group, and an alkoxy group. Carbonyl group (eg, methoxycarbonyl), aryloxycarbonyl group (eg, phenoxycarbonyl), substituted or unsubstituted carbamoyl group (eg, carbamoyl, N-phenylcarbamoyl, N, N-dimethylcarbamoyl), acyl group (eg, acetyl, benzoyl) Nitro group, substituted or unsubstituted amino group (eg, amino, dimethylamino, anilino), acylamino group (eg, acetylamino, benzoylamino), sulfonamide group (eg, methanesulfonamide), imide group (eg, succinyl) De, phthalimido), an imino group (e.g., benzylideneamino), a hydroxy group, an alkoxy group (e.g. methoxy), aryloxy group (e.g., phenoxy), an acyloxy group (e.g. acetoxy),
Alkylsulfonyloxy group (eg, methanesulfonyloxy), arylsulfonyloxy group (eg, benzenesulfonyloxy), sulfo group, substituted or unsubstituted sulfamoyl group (eg, sulfamoyl, N-phenylsulfamoyl), alkylthio group (eg, methylthio) ), An arylthio group (eg, phenylthio) alkylsulfonyl group (eg, methanesulfonyl), an arylsulfonyl group (eg, benzenesulfonyl), and heterocycles. Further, the substituents may be further substituted, and when there are a plurality of substituents, they may be the same or different. Further, the substituent may form a condensed ring with the alkyl group or the aryl group. The substituent is preferably a halogen atom, a nitro group, a cyano group, a carboxyl group, an alkoxy group, an alkyl group, a sulfo group, a sulfamoyl group, an aryl group, an aryloxy group, an acylamino group, a sulfonamide group, and a halogen atom is particularly preferable. . Particularly preferred as R ¹ is a chlorine atom of 1 to 3.
It is a phenyl group which is individually substituted.

Preferred examples of the substituent on the benzene ring represented by R ² include a halogen atom, an alkoxy group, an alkyl group, a nitro group and a cyano group. More preferred are a halogen atom, an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms, and a methyl group, a chlorine atom and a methoxy group are particularly preferred. n is preferably 0 or 1 to 2, and particularly preferably 0 or 1.

Preferred examples of the coupling-off group represented by L include a thiocyano group, an aryloxy group (for example, phenoxy, p-chlorophenoxy, p-nitrophenoxy), an alkoxy group, and an alkylthio group (for example, having 4 carbon atoms).
To 10 alkylthio), an arylthio group (eg, phenylthio), a heterocyclic thio group (eg, 2-benzothiazolylthio, 1-phenyl-5-tetrazolylthio, 2-
Benzoxazolylthio,), imide group (eg, 5,5
-Dimethyl-3-hydantoinyl), imidazolyl group (eg, 1-imidazolyl, 2-methyl-1-imidazolyl, 1-benzimidazolyl), pyrazolyl group (eg, 1-pyrazolyl, 4-methyl-1-pyrazolyl, 3,
5-dimethyl-1-pyrazolyl, 4-chloro-1-pyrazolyl, 4-bromo-1-pyrazolyl) or a triazolyl group (1-triazolyl, 3-chloro-1-triazolyl, 5,6-dimethyl-1-benzo) Triazolyl,
5-methoxycarbonyl-1-benzotriazolyl) and the like, more preferably an aryloxy group, an imidazolyl group, a pyrazolyl group and a triazolyl group,
Pyrazolyl groups are particularly preferred.

Further, typical examples of the 4-substituted-5-pyrazolones having a benzoylamino group which may have a substituent at the 3-position (general formula (I)) used in the present invention are shown below. However, the present invention is not limited to these.

[0025]

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[0026]

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[0027]

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[0028]

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[0029]

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[0030]

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[0031]

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The 4-substituted-5-pyrazolones having an optionally substituted benzoylamino group at the 3-position in the present invention can be prepared, for example, by the method described in JP-A-62-70363. Can be.

The reaction solvent that can be used in the hydrolysis step of the present invention is not particularly limited. For example, alcohol solvents such as methanol, ethanol and 2-propanol; aromatic hydrocarbon solvents such as toluene and xylene;
Amide solvents such as N, N-dimethylacetamide, N-methylpyrrolidinone, diglyme, dimethoxyethane,
Ether solvents such as 1,4-dioxane, 1,3-dioxolan, tetrahydrofuran, and anisole; ketone solvents such as acetone, methyl ethyl ketone and cyclohexanone; alkane solvents such as hexane and cyclohexane; and ester solvents such as ethyl acetate and butyl acetate. A solvent, dimethylsulfoxide, sulfolane, N, N-dimethylimidazolidinone, acetonitrile, pyridine, water and the like can be used. Further, two or more kinds of solvents may be used in combination at an arbitrary mixing ratio. The solvent is preferably an alcohol solvent, an amide solvent, an ether solvent, dimethyl sulfoxide, sulfolane, pyridine or water, more preferably an alcohol solvent, an ether solvent, sulfolane or water, and further preferably an alcohol solvent. , Sulfolane, water.

The reaction temperature in the hydrolysis step of the present invention is usually from 20 to 200 ° C., preferably from 40 to 150 ° C. The reaction time is usually 0.5 to 20 hours,
A range of 3 to 10 hours is preferred. Although an inert atmosphere is not particularly required for the reaction, it is preferable to carry out the reaction under an atmosphere such as argon or nitrogen.

The hydrolysis reaction of the present invention is performed under alkaline conditions. The base that can be used is not particularly limited, and may be an organic base or an inorganic base. For example, alkali metal or alkaline earth metal hydroxides, carbonates, bicarbonates, phosphates, carboxylates, alkoxides, amines (eg, ammonia, diethylamine, triethylamine) and the like can be used. May be used in combination. Preferred are hydroxides, carbonates, and alkoxides of alkali metals or alkaline earth metals, and specifically, sodium hydroxide, potassium hydroxide, lithium hydroxide, magnesium hydroxide, barium hydroxide, calcium hydroxide, and carbonate. Sodium, potassium carbonate, lithium carbonate, magnesium carbonate, barium carbonate, calcium carbonate, sodium methoxide and sodium ethoxide, particularly preferably sodium hydroxide, lithium hydroxide, barium hydroxide, sodium carbonate, lithium carbonate, barium carbonate , Calcium carbonate, sodium methoxide and sodium ethoxide. These may be added as powder,
It may be added as a solution having an arbitrary concentration (for example, an aqueous solution or an alcohol solution).

The amount of the base to be used in the hydrolysis step of the present invention is preferably 0.1 to 4 -substituted-5-pyrazolones having an optionally substituted benzoylamino group at the 3-position. The molar amount is 5 to 100 times, more preferably 1 to 20 times.

The hydrolysis reaction of the present invention is particularly preferably performed in the presence of a barium compound or a lithium compound. The form of the barium compound coexisting in the reaction is not particularly limited, and can be usually added as a barium salt and may be an organic salt or an inorganic salt. As barium salts, for example, barium acetate, barium carbonate, barium chloride, barium fluoride,
Examples include barium hydroxide, barium nitrate, barium oxide, barium perchlorate, barium peroxide, barium sulfate, barium chloranilate, and the like, and these barium salts may be hydrates. Preferred are barium acetate, barium carbonate, barium chloride, barium hydroxide, barium oxide and hydrates thereof.

The amount of the barium salt to be added in the hydrolysis step of the present invention is usually 0.1 to 4 with respect to the 4-substituted-5-pyrazolones having an optionally substituted benzoylamino group at the 3-position. In the range of 1 to 10 times mol, and 0.5 to 5
Double molar is more preferred.

The form of the lithium compound coexisting in the hydrolysis reaction of the present invention is not particularly limited as well as the barium compound, and can be usually added as a lithium salt, and may be an organic salt or an inorganic salt. Examples of lithium salts include lithium carbonate, lithium hydroxide, lithium chloride, lithium fluoride, lithium sulfate, lithium bromide, lithium hydride, lithium aluminum hydride, lithium boron hydride, lithium hypochlorite, lithium nitrate, Examples thereof include lithium nitrite and lithium peroxide, and these lithium salts may be hydrates. Preferred are lithium carbonate, lithium hydroxide, lithium chloride, lithium fluoride, lithium sulfate, lithium bromide and hydrates thereof.

The amount of the lithium salt to be added in the hydrolysis step of the present invention is usually 0.1 to 4 with respect to the 4-substituted-5-pyrazolones having an optionally substituted benzoylamino group at the 3-position. In the range of 1 to 20 times mol, 0.5 to 1
A 0-fold mole is more preferred.

[0041]

Next, the present invention will be described in more detail with reference to Examples.

Example 1 1.0 g of Exemplified Compound (1)
(2.23 mmol) and various bases or acids shown in Table 1 were mixed with 3 ml of methanol and stirred at 60 ° C. After 5 hours, the progress of the reaction was confirmed by HPLC.

[0043]

[Table 1]

As is evident from Table 1, it was found that alkali hydrolysis, particularly when a lithium compound or a barium compound was used, was particularly effective.

Example 2 2.0 g of Exemplified Compound (1)
(4.46 mmol) and barium hydroxide. 2.81 g (8.91 mmol) of octahydrate was mixed with 6 ml of methanol and stirred at 65 ° C. for 6 hours under a nitrogen atmosphere. Remove the hot water bath, and when the internal temperature drops to 40 ° C, oxalic acid.
2.24 g (17.77 mmol) of dihydrate are added,
The mixture was stirred at 40 ° C for 30 minutes. The reaction solution was filtered, and the precipitate was sufficiently washed with methanol. The filtrate was concentrated under reduced pressure, extracted with 20 ml of ethyl acetate, and sufficiently washed with water. After removing the aqueous layer, adding an appropriate amount of sodium sulfate to the organic layer and drying,
The precipitate was separated by filtration and concentrated under reduced pressure. This was purified by silica gel column chromatography to give 3-amino-4- (1
-Pyrazolyl) -1- (2,4,6-trichlorophenyl) -5-pyrazolone crystals were obtained. Yield 1.40 g,
91.1% yield. The structure of the target product was confirmed by ¹ H-NMR.

¹ H-NMR (300 MHz: solvent CD
Cl ₃ internal standard: TMS)

Example 3 3-Benzoylamino-4-
Bromo-1- (2,4,6-trichlorophenyl) -5
10.0 g (21.66 mmol) of pyrazolone, 4.43 g (65 mmol) of pyrazole and 2,6-di-
716 mg of tert-butyl-p-cresol (3.2
5 mmol) was mixed with 10 ml of sulfolane and stirred at 75 ° C. for 7 hours under a nitrogen atmosphere. Remove hot water bath, internal temperature is 4
When cooled to 0 ° C., barium hydroxide. Octahydrate 1
3.66 g (43.32 mmol), 25% (w / v)
3.8 ml (23.82 mmol) of sodium hydroxide solution and 10 ml of methanol were added, and the mixture was stirred at 65 ° C. for 6 hours under a nitrogen atmosphere. Remove hot water bath, internal temperature is 40
Oxalic acid when cooled to ° C. Dihydrate 11.2g
(88.8 mmol) and 10 ml of methanol were added, followed by stirring at 40 ° C. for 30 minutes. The reaction solution was filtered, and the precipitate was washed with 30 ml of methanol. After the filtrate was concentrated under reduced pressure, 20 ml of ethyl acetate was added, and the mixture was extracted twice with 30 ml of 18% hydrochloric acid. Under ice-cooling, a 25% (w / v) sodium hydroxide solution was added to the aqueous layer with stirring to adjust the pH to about 4. The resulting crystals were collected by filtration and washed with 30 ml of water.
The crystals were recrystallized from methanol to give 3-amino-4- (1
-Pyrazolyl) -1- (2,4,6-trichlorophenyl) -5-pyrazolone crystals were obtained. Yield 5.4 g, 72.2%. The structure of the target product was confirmed by ¹ H-NMR. (The conditions and assignments are the same as in Example 2.) <Example 4> 3-Amino-4- (1-pyrazolyl) -1- (2,4,6-trichlorophenyl) synthesized by the method of Example 3 of the present invention. ) -5-Pyrazolone as a raw material and a method described in JP-A-58-224352.
Photosensitive material sample 1 prepared according to the method described in Example 1 of JP-A-58-224352 by synthesizing the polymer coupler III described in JP-A-224352, and using the same.
And 3-amino-4- (1-pyrazolyl) synthesized by the method described in Example 2 (b) of JP-A-62-70363.
Using 1- (2,4,6-trichlorophenyl) -5-pyrazolone as a raw material, a polymer coupler III described in JP-A-58-224352 was synthesized by a method described in JP-A-58-224352, Using this, JP-A-58-2
A photosensitive material sample 2 (comparative example) prepared by the method described in Example 1 of Japanese Patent No.
The photographic properties were evaluated under the same conditions as in Example 1 of No. 2. Table 2 shows the results.

[0048]

[Table 2]

From the above results, it can be seen that the light-sensitive material using the polymer coupler synthesized from the raw materials synthesized by the method of the present invention has lower fog and gives preferable photographic properties as compared with Comparative Examples.

[0050]

According to the present invention, 3-amino-4-substituted-5-pyrazolones useful as, for example, coupler intermediates for photographic light-sensitive materials and color marking material intermediates can be efficiently produced.

Claims (4)

[Claims] 1. A process for alkaline hydrolysis of a benzoylamino group of a 4-substituted-5-pyrazolone having a benzoylamino group which may have a substituent at a 3-position. A method for producing amino-4-substituted-5-pyrazolones. 2. The 4-substituted-5-pyrazolones having a benzoylamino group which may have a substituent at the 3-position is represented by the following general formula (I).
The production method described in 1. Embedded image In the formula, L represents a thiocyano group, an aryloxy group, an alkoxy group, an alkylthio group, an arylthio group, a heterocyclic thio group, an imide group, an imidazolyl group, a pyrazolyl group, or a triazolyl group. R ¹ represents an unsubstituted or substituted alkyl group or an unsubstituted or substituted aryl group; R ² represents a substituent on a benzene ring;
Represents an integer. When n is 2 or more, a plurality of R ² may be the same or different. 3. The method according to claim 1, wherein the alkaline hydrolysis is performed in the presence of a barium compound. 4. The method according to claim 1, wherein the alkaline hydrolysis is performed in the presence of a lithium compound.