JPH0322380B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved method for producing phenolic cyan couplers.

Generally, in silver halide color photographic light-sensitive materials, the color light-sensitive material after exposure is reduced with an aromatic primary amine color developing agent, and the oxidation product of the color developing agent produced at this time,
A color image can be obtained by reacting couplers capable of developing yellow, magenta, and cyan colors through oxidative coupling to form a dye image consisting of the three colors described above.

The couplers that develop yellow, magenta, and cyan colors are usually contained in the constituent layers of the color photosensitive material, but they may also be used together with the color developing agent and the like in a color developer. .

Among the above-mentioned couplers that develop three colors, the couplers used to form cyan dyes are phenolic couplers or naphthol couplers. As a method for producing a 5-acylamino type phenolic coupler, which is particularly useful among the above-mentioned phenolic couplers, the following reaction method is generally known.

In the above reaction formula, R ¹ X represents an acylating agent or sulfonylating agent such as acyl chloride or sulfonyl chloride, and R ² represents a palast group. Further, Y represents a hydrogen atom or a group capable of being eliminated during a coupling reaction with an oxidized product of a color developing agent.

Attempts to variously change the type of residue of the acylating agent represented by R ^{1 without changing the palast group represented by R 2 in} the above compound () resulted in the following:
This is a synthetic method that is always used in coupler manufacturing technology. However, according to traditional manufacturing methods,
If you try to change only R ¹ without changing R ² above, as shown in the reaction process above, at least () ~
It requires the four steps in parentheses and cannot be called an efficient manufacturing method. In addition, since the starting material compound () contains a nitro group, which is an electron-withdrawing group, the use of weak acylating agents or sulfonylating agents such as dimethylcarbamoyl chloride or dimethylsulfamoyl chloride may Compound () is difficult to obtain. Furthermore, since the above reaction step includes a reduction reaction, for example, benzoyl chloride having an aromatic ring is used as the acylating agent, and this aromatic ring has a reducing effect such as a nitro group or a benzyl group. However, if the compound is substituted, the nitro group or benzyl group, which should not be reduced, will also be subjected to the reduction action, so the desired compound () will not be obtained. become. Also, since compound () is easily oxidized,
Isolation is difficult, and therefore the ballast group introduction reaction must be carried out in the atmosphere of the reduction reaction solution, or cumbersome operations such as introducing nitrogen gas are required.

There are several drawbacks to the well-known method for producing the above-mentioned phenolic cyan couplers.

Therefore, an object of the present invention is to eliminate the drawbacks of the conventional methods, namely, to eliminate the troublesome operation, and to be efficient.
Furthermore, it is an object of the present invention to provide an improved method for producing phenolic couplers, which yields highly pure synthetic products.

As a result of various studies, the present inventors have found that the above object can be achieved by reacting a 5-acylamino-2-aminophenol compound with an acylating agent or a sulfonylating agent. .

That is, when the method for producing a phenolic cyan coupler according to the present invention is expressed as a chemical reaction, it is expressed as follows.

In the above reaction formula, R ₁₁ (R ₁₂ )N-X ₀ represents an acylating agent or a sulfonylating agent, and specifically, R ₁₁ and R ₁₂ are each a hydrogen atom, a lower alkyl group, a substituted or unsubstituted represents a substituted phenyl group,
They may be the same or different,
X ₀ is −CO, −COX ₁ , −COOR ₁₃ , −CS, −
Represents a group arbitrarily selected from _SO2X1 , _X1 represents _a halogen atom, _R13 represents a substituted or unsubstituted phenyl group, and Link represents -CO- or _-SO2- .

R ² represents a ballast group, preferably a straight or branched alkyl group having 4 to 30 carbon atoms (for example, t
-butyl group, n-octyl group, t-octyl group,
n-dodecyl group, etc.), alkenyl group, aralkyl group, aralkenyl group, alkoxyalkyl group,
It represents a substituted or unsubstituted cycloalkyl group, a 5- or 6-membered heterocyclic group, or a group represented by the following general formula ().

General formula () In the formula, J is an oxygen atom or a sulfur atom, ^R6 is a linear or branched alkyl group having 1 to 20 carbon atoms,
R ⁷ is a hydrogen atom, a halogen atom (preferably chloro, bromo), an alkyl group {preferably a linear or branched alkyl group having 1 to 20 carbon atoms (e.g. methyl, tert-butyl, tert-pentyl, tert-octyl, dodecyl, pentadecyl)}, aryl groups (e.g. phenyl), heterocyclic groups (preferably nitrogen-containing heterocyclic groups), aralkyl groups (e.g. benzyl,
phenethyl), alkoxy groups {preferably linear or branched alkyloxy groups having 1 to 20 carbon atoms (e.g., methoxy, ethoxy, tert-butyloxy, octyloxy, decyloxy, dodecyloxy)}, aryloxy groups (e.g., phenoxy), hydroxy group, acyloxy group {preferably substituted or unsubstituted alkylcarbonyloxy group, arylcarbonyloxy group (e.g. acetoxy, benzoyloxy)}, carboxy group, alkoxycarbonyl group (preferably substituted or unsubstituted carbon straight-chain or branched alkyloxycarbonyl having 1 to 20 carbon atoms), aryloxycarbonyl group (preferably substituted or unsubstituted phenoxycarbonyl), mercapto group, alkylthio group (preferably straight-chain or branched alkyloxycarbonyl having 1 to 20 carbon atoms) (branched substituted or unsubstituted benzenesulfonyl), acyl group (preferably linear or branched allylcarbonyl having 1 to 20 carbon atoms), acylamino group (preferably linear or branched alkylcarbonyl having 1 to 20 carbon atoms) , substituted or unsubstituted benzenecarboxamide), sulfonamide group (preferably a linear or branched substituted or unsubstituted alkylsulfonamide group having 1 to 20 carbon atoms, substituted or unsubstituted benzenesulfonamide group), carbamoyl group (preferably linear or branched alkylaminocarbonyl having 1 to 20 carbon atoms, substituted or unsubstituted phenylaminocarbonyl), sulfamoyl group (preferably linear or branched alkylaminosulfonyl having 1 to 20 carbon atoms), (substituted or unsubstituted phenylaminosulfonyl), m represents an integer of 1 to 4, and l represents an integer of 0 or 1, respectively.

In addition, Y is a hydrogen atom or a group that can be eliminated during the coupling reaction with the oxidized product of the color developing agent (for example, a halogen atom (e.g., chlorine, bromine, fluorine, etc.), an oxygen atom or a nitrogen atom at a direct coupling position). Examples include an aryloxy group, a carbamoyloxy group, a carbamoylmethoxy group, an acyloxy group, a sulfonamide group, a succinimide group, and more specific examples include,
U.S. Pat.
No. 117422, No. 50-130441, No. 51-108841, No. 117422, No. 50-130441, No. 51-108841, No.
No. 50-120334, No. 52-18315, No. 53-52423,
53-105226 and other publications}.

The 5-acylamino-2-aminophenol used in the production of the compound (), which is the target phenolic cyan coupler in the present invention, has the production shown in the compound () above, and this compound is a 5-nitrocyanic coupler. It can be synthesized by the following steps using -2-aminophenol as a starting material.

In the above reaction formula, R ₂ and Y are as described above, and Z represents a hydrogen atom, an alkyl group (e.g., methyl group, ethyl group, etc.), an alkoxy group (e.g., methoxy group, ethoxy group, etc.), or a halogen atom. .

That is, the method for producing a phenolic cyan coupler of the present invention is characterized in that an acylating reagent is applied to 2-aminophenol into which a ballast group has been introduced at the 5-position to acylate the amino group at the 2-position. The process is naturally different from the conventional production method in which an acyl group is first introduced into the amino group at the 2-position, and then a ballast group is substituted into the amino group at the 5-position. It is meant to be.

And in the step of producing the compound (),
There are no various disadvantages in the synthesis technology that are found in the conventional manufacturing process described above, the operation is simple, the yield is high, and the purity of the obtained compound is also high.

Next, the above manufacturing steps will be sequentially explained.

(1) Synthesis method of compound (V-2) from compound (-1) An acylation reaction is performed on the above-mentioned compound (-1) using a commonly used acylating agent. A preferred acylating reagent is benzyl chloroformate, which is used in a range of about 0.9 equivalents to 2.0 equivalents, preferably 1.0 equivalents to 1.5 equivalents, and the reaction temperature is 10°C to
A temperature of 100°C and a reaction time of 1 to 5 hours are appropriate.
Examples of the base used in the reaction catalyst include organic bases such as pyridine, triethylamine, and quinoline, and inorganic bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and sodium acetate. The amount is 1.0
The range is from equivalent to 4.0 equivalent. These bases do not necessarily have to be used. As the reaction solvent, solvents used in normal acylation reactions, such as DMF,
Acetone, ethyl acetate, acetonitrile, benzene, acetic acid, etc. are suitable. The most preferred reaction conditions are to add 1.2 mol of benzyl chloroformate to compound (-1), and boil and reflux the mixture using acetonitrile as a solvent without using a base. In this way, compound (-2) can be obtained in good yield.

(2) Synthesis method of compound (V-3) from compound (-2) Although this reaction is a reduction, chemical reduction using hydrazine or iron is particularly preferred. The reduction reaction using hydrazine can be carried out, for example, according to the method described in Journal of the Chemical Society of Japan, 1975, No. 7, p. 1223. Regarding the reduction reaction with iron, reduced iron equivalent to 3 to 30 equivalents of compound (-2) is used, preferably 3 to 10 equivalents.
Equivalent range. The reaction temperature is 60° to 110°C, and the solvent used is preferably hydrofuran or dioxane.

(3) Synthesis method of compound (-4) from compound (-3) This reaction step is an acylation reaction, but the reaction conditions are the same as in (1) above by simply changing the acylating agent.
It is preferable to carry out the reaction under the same conditions as in the case of .

(4) Synthesis method of compound () from compound (-4) The reaction in this step can be carried out under normal hydrogenolysis reaction conditions. Preferred conditions for this reaction include using methanol, ethanol, or tetrahydrofuran as a solvent, and using palladium-carbon as a catalyst in a range of 5 to 50% relative to compound (-4), and allowing the reaction to occur at room temperature and pressure. . Although carbamic acid is thought to be produced as a reaction intermediate in this reaction step, the final product can be obtained in the next step without the need for any treatment that causes decarboxylation (e.g., by addition of acid). Therefore, it is considered that the decarboxylation reaction occurs under the reaction conditions of the above-mentioned hydrogenolysis or the post-treatment conditions of the reaction.

The manufacturing process for compound (), which is a raw material for the synthesis of compound (), which is the phenolic cyan coupler of the present invention, is as described in detail above.

Next, a synthetic method for producing the compound (2), which is a phenolic cyan coupler according to the present invention, from the compound (2), which is a feature of the present invention, will be described.

The above reaction is as shown in the chemical reaction formula above,
This is carried out by reacting the compound () with an acylating reagent R ₁₁ (R ₁₂ )N-X ₀ . So above R ₁₁
(R ₁₂ ) When an acylating reagent having a halogen atom -CO- group or a halogen atom -SO ₂ - group as N-X ₀ is used, 1.0 for the compound ()
Equivalents to 2.0 equivalents of acylating reagent are used,
Preferably it is in the range of 1.0 equivalent to 1.5 equivalent. The appropriate reaction temperature is 10° to 100°C, and the reaction time is 1 to 24 hours. In addition, as a base for the reaction catalyst,
Organic bases such as pyridine, triethylamine, quinoline, and sodium hydroxide, potassium hydroxide,
Inorganic bases such as sodium carbonate and sodium acetate are used, and the amount used is preferably 1 to 10 equivalents based on the compound (). However, the purpose of the present invention can be achieved even without the need for these bases. In addition, as a solvent, a solvent normally used in an acylation or sulfonylation reaction is used, but in the present invention, a pyridine solvent or a
Schotten-Bauman reaction conditions may also be used.
In addition, as the acylation reagent R ₁₁ (R ₁₂ )N-X ₀ -
When using an acylation reagent having an NCS group or a -NCO group, the acylation reaction can be carried out using reaction conditions used for isocyanate reactions and isothiocyanate reactions. . Further above
When R ₁₁ (R ₁₂ )N-X ₀ is used as an acylating reagent having a -CO ₂ R ⁵ group, the acylating reagent is used in an equivalent amount or slightly in excess of the compound (),
Imidazole is present as a reaction catalyst in an amount of 0.1 to 1.0 equivalents relative to the compound (), and benzene, toluene, or xylene is used as a solvent.
The acylation reaction is carried out at a reaction temperature of 80° to 150°C.

Alternatively, without using the above solvent,
Also preferred is a method in which the phenol derivative produced is distilled off under reduced pressure. Also acylation reagent
_When R ¹

Specific examples of the phenolic cyan coupler according to the present invention obtained by the production process and reaction conditions described in detail above are described below, but the present invention is not limited thereto.

(Exemplary compound) Next, the method for synthesizing the compound (), which is a raw material for synthesizing the phenolic cyan coupler according to the present invention, will be described in more detail as a synthesis example.

Synthesis Example 1 Synthesis of 2-amino-5-[α-(2,4-di-t-pentylphenoxy)butanamide]phenol 154 g of 2-amino-5-nitrophenol and 570 g of benzyl chloroformate (30% toluene solution) were boiled and refluxed in 1500 ml of acetonitrile for 5 hours.
After refluxing, acetonitrile was distilled off under reduced pressure, water was added to the residue, and solids were collected. The obtained solid was recrystallized from methanol to obtain 250 g of a colorless solid having a melting point of 194° to 196°C.

Dissolve 288 g of the compound obtained in step a above in 3000 ml of tetrahydrofuran, and add 335 g of reduced iron to this solution.
After refluxing, the reaction mixture was filtered on filter paper lined with activated carbon. The solid obtained by drying the filtrate under reduced pressure was collected, washed with toluene, and the melting point
203 g of a light brown solid with a temperature of 142 DEG -143 DEG C. was obtained.

Dissolve 561 g of the compound obtained in step b above in 5000 ml of ethanol, and add palladium-carbon to the solution.
112 g was added and hydrogenolysis was carried out at room temperature and pressure.

After absorbing the theoretical amount of hydrogen gas, the catalyst was filtered off. The filtrate was concentrated under reduced pressure, and the residue was crystallized from cyclohexane and collected by suction filtration.
380 g of a colorless solid with a melting point of 109 DEG -110 DEG C. was obtained. Other 2-amino-5-acylaminophenols could be similarly obtained using this method.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 2-di-N,N-dimethylureido-5-[α
Synthesis method of -(2,4-di-t-pentylphenoxy)butanamide]phenol (Exemplified Compound 2) 2-Amino-5- obtained in Synthesis Example 1
[α-(2,4-di-t-pentylphenoxy)butanamide] 42.7 g of phenol was dissolved in 500 ml of pyridine, 11.8 g of N,N-dimethylcarbamoyl chloride was added at room temperature, and the mixture was incubated at the same temperature for 24 hours. Stirred. After stirring, the reaction solution was poured into ice water containing dilute hydrochloric acid, and the separated oil was extracted with ethyl acetate.
After washing this extraction solution with water, only the ethyl acetate layer was separated, dried over magnesium sulfate, and concentrated to obtain an extract. This extracted reaction crude product was isolated and purified using silica gel column chromatography.
36.4 g of a slightly brown solid with a melting point of 127 DEG -128 DEG C. was obtained.

In this way, exemplified compound (2), which was difficult to obtain using conventional synthesis methods, could be obtained in good yield. In addition, N,N-dimethylsulfamoyl chloride may be used to react in the same manner,
Exemplary compound (1) (mp 130-131°C) could be obtained.

Example 2 2(3-nitrophenyl)ureido-5-[α-
Synthesis method of (2,4-di-t-pentylphenoxy)butanamide]phenol (Exemplary Compound 6) 2-Amino-5- obtained in Synthesis Example 1
[α-(2,4-di-t-pentylphenoxy)butanamide] 42.7 g of phenol and 16.4 g of m-nitrophenyl isocyanate were dissolved in 600 ml of toluene and allowed to stand at room temperature for 24 hours. After standing, toluene was distilled off under reduced pressure, and the reaction crude product was isolated and purified using silica gel column chromatography. Fractions containing the target product were collected and dried under reduced pressure, and the residue was crystallized by adding hexane-toluene. This is collected by suction filtration and is a pale yellow solid with a melting point of 146° to 148°C.
45.2g was obtained.

In this way, exemplary compound (6), which could not be obtained by conventional synthesis methods, could be obtained in good yield.

Example 3 Synthesis method of 2-(4-ethylsulfonylphenyl)ureido-5-[α-(2,4-di-t-pentylphenyxy)butanamide]phenol (exemplified compound (10) According to Synthesis Example 1 above) The obtained 2-amino-5-
[α-(2,4-di-t-pentylphenoxy)butanamide] 42.7 g of phenol and phenyl-p-
30.5 g of ethylsulfonylphenyl carpamate and 1.4 g of imidazole were dissolved in 600 ml of toluene and boiled under reflux for 2 hours. After refluxing, the reaction solution was concentrated under reduced pressure, and the crude product was isolated and purified using silica gel column chromatography. 553g light brown caramel
I got it.

Claims (1)

[Claims] 1. A method for producing a phenolic cyan coupler, which comprises reacting a 5-acylamino-2-aminophenol compound with an acylating agent or sulfonylating agent represented by the following general formula [A]. . General formula [A] R ₁₁ (R ₁₂ )N-X ₀ In the formula, R ₁₁ and R ₁₂ each represent a hydrogen atom, a lower alkyl group, or a substituted or unsubstituted phenyl group, and may be the same or different. X ₀ is −CO, −COX ₁ , −COOR ₁₃ , −CS, −
Represents a group arbitrarily selected from SO ₂ X ₁ , where X ₁ represents a halogen atom and R ₁₃ represents a substituted or unsubstituted phenyl group.