JPH09301978A - Production of 1h-pyrazolo(3,2-c)-1,2,4-triazol-based compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce 1H-pyrazolo[3,2-c]-1,2,4-triazol-based compound useful as a coupler (intermediate) for a photograph, an intermediate for an organic synthesis, etc., in high yield by reacting a specific 1H-pyrazolo[3,2-c]-1,2,4-triazol derivative in the presence of Br<-> , I<-> , phosphorous acid (triester), etc. SOLUTION: A derivative of a 1H-pyrazolo[3,2-c]-1,2,4-triazol-based compound of formula I (R<1> is an alkyl, an alkoxycarbonyl, an aryloxycarbonyl, carboxyl or carbamoyl; R<2> and R<3> are each an alkyl, an aryl or a heterocycle) is reacted in the presence of at least one kind of bromide ion, iodide ion, phosphorous acid, a phosphorous acid triester, etc., to provide the objective 1H-pyrazolo[3,2- c]-1,2,4-triazol-based compound of formula II (R<l> is an alkyl, an alkoxycarbonyl, aryloxycarbonyl, carboxyl, carbamoyl) useful as a coupler or a coupler intermediate for a photograph, an intermediate for an organic synthesis, etc., in high yield.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing a 1H-pyrazolo [3,2-c] -1,2,4-triazole compound useful as a photographic coupler and its intermediate or an intermediate in organic synthesis. Regarding

[0002]

1H having a substituent or a hydrogen atom at the 7-position
The -pyrazolo [3,2-c] -1,2,4-triazole-based compound is a compound useful as a photographic coupler and its intermediate, or an intermediate in organic synthesis.

1 having an alkoxycarbonyl group at the 7-position
Examples of H-pyrazolo [3,2-c] -1,2,4-triazole-7-carboxylate compounds include, for example, British Patent 1,252,418, U.S. Patent 3,725,067 or Journal of. The Chemical Society Perkin I (J. Chm. Soc. Perkin
I), 1977, 2047-2052. That is, it can be obtained by refluxing a 5-acylhydrazino-1H-pyrazole-4-carboxylate compound in benzene with phosphorus oxychloride for a long time. However, this method requires a long reaction time, particularly 1H-pyrazolo [3,2-c] -1,2,4-triazole-7-carboxylate having a secondary or tertiary alkyl group at the 3-position. The system compounds have problems that they require a longer reaction time and that the yield is low.

Research Disclosure (Res)
(Each Disclosure, abbreviated as RD) 12
In 443, 1H-pyrazolo [3,2 in which the 7-position is a hydrogen atom
A method for synthesizing -c] -1,2,4-triazole compound is shown. However, in this method, 1,2,4-triazolo [3,4-b] -1,3,4-thiadiazine-based compound is subjected to 1H-pyrazolo [3,2-c]-in a desulfurization step.
20 to obtain a 1,2,4-triazole compound,
It requires a high temperature of 0 ° C. or higher, and not only the desulfurization reaction progresses but also the decomposition of the mother nucleus progresses, resulting in a serious decrease in yield.

Further, in JP-A-63-231341, 7-position-unsubstituted 1,2,4-triazolo [3,4-b] -1,
1 by reaction of 3,4-thiadiazine compounds with acetic anhydride
A method for obtaining an H-pyrazolo [3,2-c] -1,2,4-triazole compound is described. However, this method also has a problem that the yield is lowered in some cases due to the substituents at the 3-position or the 6-position.

[0006]

Accordingly, the object of the present invention is to provide 1H-pyrazolo [3,2-, which is useful as a photographic coupler or its intermediate, or as an intermediate in organic synthesis.
c] -1,2,4-Triazole compound is to provide a novel method for producing a high yield.

[0007]

The above object of the present invention has been attained by the following constitutions.

(1) The compound represented by the general formula [I] is reacted in the presence of at least one of bromide ion, iodide ion, phosphorous acid or phosphorous acid triester.
1H-pyrazolo [3, which produces a compound represented by the formula I]
A method for producing a 2-c] -1,2,4-triazole compound.

[0009]

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In the formula, R ₁ and R ₁₁ are each an alkyl group,
It represents an alkoxycarbonyl group, an aryloxycarbonyl group, a carboxyl group or a carbamoyl group, and R ₂ and R ₃ each represent an alkyl group, an aryl group or a heterocyclic group.

(2) R ₁ in the general formula [I] and R ₁₁ in the general formula [II] are alkoxycarbonyl groups,
1H-pyrazolo [3,2-c] -1, as described in (1), which is an aryloxycarbonyl group or a carboxyl group.
A method for producing a 2,4-triazole compound.

Hereinafter, the present invention will be described in detail.

In the above general formulas [I] and [II], R
Examples of the alkyl group represented by ₁ and R ₁₁ include methyl, ethyl, propyl, i-propyl, butyl, sec-butyl, t-butyl and pentyl groups. Examples of the alkoxycarbonyl group include methoxycarbonyl,
Examples of the aryloxycarbonyl group such as an ethoxycarbonyl group include a phenoxycarbonyl group. Moreover, examples of the carbamoyl group include an ethylaminocarbonyl group and a butylaminocarbonyl group.

R ₁ and R ₁₁ are preferably an alkoxycarbonyl group, an aryloxycarbonyl group and a carboxyl group, and particularly preferably an alkoxycarbonyl group.

Examples of the alkyl group represented by R ₂ and R ₃ include methyl, ethyl, i-propyl, butyl, hexyl, decyl and dodecyl groups. As the aryl group, for example, a phenyl group, and as the heterocyclic group,
Examples include 2-pyridyl and 3-pyridyl groups.

R ₂ is preferably an aryl group,
R ₃ is preferably an alkyl group, particularly a methyl group.

Each of the substituents represented by R ₁ , R ₁₁ , R ₂ and R ₃ may further have a substituent.

Next, typical examples of the compounds represented by the general formula [I] or [II] are shown below, but the present invention is not limited thereto.

[0019]

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[0020]

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[0021]

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[0022]

[Chemical 6]

[0023]

[Chemical 7]

[0024]

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The compound of the general formula [I] is disclosed in JP-A-63-2
It can be produced by reacting a compound represented by the following general formula [III] with a carboxylic acid chloride or a carboxylic acid anhydride according to the production method described in No. 31341.

[0026]

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In the formula, R ₂₁ and R ₂ have the same meanings as R ₁ , R ₁₁ and R _{2 in the} above general formulas [I] and [II], and specific examples thereof are also the general formulas [I] and [II]. ] The same groups as those described above can be mentioned.

The carboxylic acid chloride or carboxylic acid anhydride used in the production of the compound of the general formula [I] is not particularly limited, but acetyl chloride or acetic anhydride is preferable, and acetic anhydride is particularly preferable.

The compound of general formula [II] can be obtained by reacting the compound of general formula [I] in the presence of at least one of bromide ion, iodide ion, phosphorous acid or phosphorous acid triester.

The bromide ion is, for example, hydrobromic acid,
It is added as sodium bromide or potassium bromide, and iodide ion is added as, for example, hydroiodic acid, sodium iodide or potassium iodide. Among these, sodium iodide and potassium iodide are preferable.

The amount of bromide ion or iodide ion added is 0.01 to 50 per mol of the compound of the general formula [I].
The amount is preferably mol, more preferably 0.1 to 5 mol, and particularly preferably 0.3 to 2 mol.

Examples of the phosphite triester include trimethyl phosphite, triethyl phosphite, tributyl phosphite, trioctyl phosphite and the like.

The addition amount of phosphorous acid or phosphorous acid triester is 0.05 to 20 per mol of the compound of the general formula [I].
The amount is preferably mol, more preferably 0.5 to 5 mol, and particularly preferably 1 to 2 mol.

The bromide ion, iodide ion, phosphorous acid, and phosphorous acid triester may be used alone, but when two or more kinds are used in combination, a remarkable effect is obtained.
Further, the general formula [II] can be obtained in an extremely high yield, which is preferable. In particular, bromide ion, iodide ion and phosphorous acid
It is preferable to use them together.

The reaction solvent is not particularly limited, and alcohol solvents such as methanol, ethanol and butanol; carboxylic acid solvents such as acetic acid and propionic acid; water,
An aqueous solvent such as hydrochloric acid is preferably used.

The reaction temperature is preferably 60 to 200 ° C., and 9
0-120 ° C is particularly preferred. It is also preferable to carry out the reaction in an inert gas such as nitrogen or argon.

[0037]

EXAMPLES Hereinafter, specific examples of the present invention will be described.
Aspects of the invention are not so limited.

Example 1 Synthesis of Exemplified Compound II-1 (run-1) 3.0 g (6.80 mmol) of Compound I-1 was added to 15 ml of acetic acid and 15 ml of 36% hydrochloric acid under a nitrogen stream at 100 ° C. And reacted for 5 hours. After the completion of the reaction, the crystals (II-1) that were left standing to cool and separated were filtered, washed with water and dried to obtain the yield. At the same time, the purity of the obtained crystals was determined by high pressure liquid chromatography.

(Run-2 to 8) r was carried out in the same manner except that the reaction reagents of run-1 were changed as shown in Table 1.
Un-2 to 8 were performed to determine the yield and purity of the obtained II-1.

The results are shown in Table 1.

[0041]

[Table 1]

As is clear from Table 1, the purity of the obtained compound II-1 is improved by the reaction in the presence of bromide ion or iodide ion and / or in the presence of phosphorous acid. Further, in the presence of iodide ion, the purity of Compound II-1 obtained by the reaction in the presence of bromide ion is higher and preferable, and the reaction in the presence of bromide ion, iodide ion and phosphorous acid is more preferable. It is understood that the target compound can be obtained with high purity and is particularly preferable.

Example 2 Exemplified compound II-1 was synthesized according to the following scheme.

[0044]

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I) Synthesis of I-1 357 g (1 mol) of compound III-1 was added to acetic anhydride 70
The reaction was carried out in 0 ml under heating and reflux for 2 hours. After completion of the reaction, the solvent was distilled off under reduced pressure to obtain I-1. I-1 was used in the next step without purification.

Ii) Synthesis of II-1 2 liters of acetic acid and 48% hydrobromic acid 2 were added to I-1 obtained in i.
1 liter, 82.0 g (1 mol) of phosphorous acid and 332 g (2 mol) of potassium iodide were further added, and the mixture was reacted at 95 to 100 ° C. for 4 hours under a nitrogen stream.

After completion of the reaction, the crystals are allowed to cool and the precipitated crystals are collected by filtration and washed with water to give the desired exemplified compound II-1.
291 g (yield 98%, purity 99% by high pressure liquid chromatography) were obtained.

Melting point 282 ° C., ¹ H-NMR (DMSO-
δ values in _{d 6); 13.7ppm (1H,} br, -CO
OH or = NH), 13.1 ppm (1H, br,
-COOH or = NH), 8.57 ppm (1H,
d, Ar), 8.32 ppm (1H, dd, Ar),
7.90 ppm (1H, d, Ar), 6.42 ppm
(1H, s, 7-H) Example 3 Exemplified Compound II-1 to Exemplified Compound II as shown in the following scheme.
-18 was synthesized.

[0049]

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I) Synthesis of intermediate (a) 1750 g (5.90 mol) of II-1, 14 l of acetonitrile, 740 ml of acetic anhydride and 480 ml.
The pyridine is reacted under heating and reflux for 4 hours. The reaction solution cooled to room temperature was slowly poured into an aqueous solution of 516 ml of 35% hydrochloric acid and 12 liters of water, and the precipitated crystals were collected by filtration, washed twice with 3 liters of water and 4 liters of acetonitrile, and dried. Thus, 1975 g (yield 99%) of the intermediate (a) was obtained.

Ii) Synthesis of intermediate (b) 1620 g (6 mol) of stearyl alcohol, 703
g (6 mol) of L-valine and 1370 g (7.2 mol) of p-toluenesulfonic acid monohydrate were added to 10 parts of toluene.
In a liter, the reaction is carried out for 8 hours while boiling and refluxing while removing the produced water.

Crystals which precipitate after the reaction (intermediate (b))
Of p-toluenesulfonate) is collected by filtration. The crystals are dispersed in 10 liters of toluene and washed 3 times with 5 liters of a 5% sodium hydrogen carbonate aqueous solution. Then, the organic layer was concentrated under reduced pressure to give 1885 g of intermediate (b) (yield 85%).
obtain.

Iii) Synthesis of coupler II-18 1700 g (5.01 mol) of (a) was dispersed in 17 liters of toluene and 10 g of N, N-dimethylformamide, and 1790 g (15.0 mol) of thionyl chloride was added thereto. The reaction is carried out at 70 ° C. for 5.5 hours. After completion of the reaction, the solvent is recovered under reduced pressure, 6 liters of toluene is further added, and then the solvent is recovered under reduced pressure again.

The obtained residue was dispersed in 17 liters of ethyl acetate, and 3.2 liters of a solution prepared by dissolving 1852 g (5.01 mol) of (b) in 3.2 liters of ethyl acetate was added dropwise at room temperature. Thereafter, 319 g of sodium carbonate (3.
3 liters of an aqueous solution containing (01 mol) is added dropwise. After completion of dropping, the reaction is allowed to proceed at room temperature for 2 hours, 1310 ml of 29% aqueous ammonia is added dropwise, and the reaction is allowed to proceed at room temperature for 1 hour.

After completion of the reaction, the reaction mixture is neutralized with diluted hydrochloric acid and the organic layer is extracted at about 40 ° C. The organic layer is 1 with 4 liters of 2% hydrochloric acid water.
After washing 5 times with 4.5 liters of water, the mixture is dried under reduced pressure.

To the obtained residue, 9.7 liters of ethanol was added, heated and dissolved, and 65 g of activated carbon was added, and the temperature was about 60 ° C.
After hot filtration with, the mixture is allowed to cool with stirring and recrystallized. The precipitated crystals were collected by filtration and washed with 5 liters of ethanol to obtain 2919 g (yield 90%) of the target compound II-18. Melting point 103-104 [deg.] C. The structure was confirmed by NMR.

This compound was useful as a photographic cyan coupler.

[0058]

As is clear from the examples, according to the production method of the present invention, 1H-pyrazolo [3,2-c] -1,2,4-triazole useful as a photographic coupler or its intermediate is useful. The system compound can be obtained in high yield and high purity.

Claims (2)

[Claims] 1. A compound represented by the general formula [II] is obtained by reacting a compound represented by the general formula [I] in the presence of at least one of bromide ion, iodide ion, phosphorous acid or phosphorous acid triester. A method for producing a 1H-pyrazolo [3,2-c] -1,2,4-triazole compound, which comprises producing the compound. Embedded image [Wherein, R ₁ and R ₁₁ each represent an alkyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carboxyl group or a carbamoyl group, and R ₂ and R ₃ respectively represent
It represents an alkyl group, an aryl group or a heterocyclic group. ] 2. The 1H-pyrazolo according to claim 1, wherein R ₁ in the general formula [I] and R ₁₁ in the general formula [II] are an alkoxycarbonyl group, an aryloxycarbonyl group or a carboxyl group. [3,2-
c] A method for producing a 1,2,4-triazole compound.