JPH08193065A - Production of imino compound - Google Patents

Abstract

PURPOSE: To simply obtain an imino compound which is useful as an intermediate for pigments or as a heat-sensitive color-developing material in high yield by effecting the reaction of a specific cyclic dioxo compound with urea, as these reactants are sealed with ammonia without exposure to the air with use of reactants easy to handle. CONSTITUTION: The reaction of (A) a compound of formula I [A<2> is O, NH; Z is an aromatic or heterocyclic group which can form a conjugated system with -C(=NH)-] with (B) urea is carried out in the presence of (C) a catalyst 12-molybdophosphoric acid, 12-molybdosilicic acid, as the reaction mixture is sealed with ammonia without exposure of these reactants to the air to give this compound of formula II, typically 3-iminoisoindolin-1-one or 1,3- diiminoisoindoline.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for producing an imino compound which is useful as an intermediate for pigments and as a thermosensitive coloring material.

[0002]

2. Description of the Related Art The following general formula (1)

[0003]

Embedded image

(In the formula, A ¹ represents O or NH, and Z represents an aromatic ring group or a heterocyclic group capable of forming a conjugated system with a> C═NH group.) (Hereinafter referred to as an imino compound) , Abbreviated as compound 1) is represented by the general formula (2)

[0005]

[Chemical 4]

A method for producing a compound represented by the formula (A ² represents O or NH; Z is the same as in the general formula (1)) (hereinafter abbreviated as compound 2) as a raw material has long been known. Are known. As a general method, Angew. Ch
em. / 68. Jahrg. 1956 / Nr. 4 to 3
After adding chlorine to phosphorus chloride and phosphorus oxychloride to form phosphorus pentachloride, it is reacted with tetrachlorophthalimide to give 1,
A method of synthesizing 1,3-diimino-4,5,6,7-tetrachloroisoindoline by obtaining 3,3,4,5,6,7-heptachloro-isoindolenine and further reacting with ammonia is shown. Has been done. This method can obtain the desired product even if phthalic anhydride having a substituent is used as a raw material, but on the other hand, it requires a difficult-to-handle reactive agent such as phosphorus pentachloride that is fuming and has a long reaction process. There was a point.

Japanese Patent Publication No. 29-3324 discloses a method for producing 1,3-diiminoisoindoline by reacting phthalic anhydride with urea in the presence of a catalyst such as ammonium molybdate. . This method can obtain a target product in a relatively high yield when using unsubstituted phthalic anhydride as a raw material, but at least 5 byproducts are produced.
Generate about%. Also, Angew. Chem. / 6
8. Jahrg. 1956 / Nr. If phthalic anhydride is replaced with an electron withdrawing group, as described in 4, then this is not the preferred method. Therefore, there has been a demand for a method of synthesizing Compound 1 in a higher yield.

The present inventors have found that compound 1
We have previously found a method of using a heteropolyacid in which the polyacid atom is molybdenum, as a method for producing the above in a high yield. (Specification of Japanese Patent Application No. 5-264068) By the way, all of the compounds 1 are useful as intermediates for pigments and thermosensitive coloring materials. Especially when it is used as a thermosensitive coloring material, a compound in which A ¹ is O (hereinafter abbreviated as A ¹ O).
Therefore, a compound in which A ¹ is NH (hereinafter, abbreviated as A ¹ NH)
Is more preferable in terms of sensitivity. The reaction produces A ¹ NH via A ¹ O. Heretofore, no method has been known for efficiently increasing the ratio of A ¹ NH to A ¹ O without increasing the production of by-products.

Further, when the compound 1 is used as a thermosensitive color developing material, it is desired that the compound 1 is not colored as much as possible until it is colored.

[0010]

OBJECTS OF THE 0008] The present invention is, when manufacturing the compound 1 compound 2 as a raw material, without using such reagents the phosphorus pentachloride, the yield, and A ¹
An object of the present invention is to provide a method for increasing the ratio of A ¹ NH to O and efficiently producing an imino compound without coloring it.

[0011]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that the reaction can be achieved by using a specific method, and the object can be achieved. It came to completion. That is, the present invention provides [1] the following compound 1

[0012]

Embedded image

(Wherein A ¹ represents O or NH, and Z represents an aromatic ring group or a heterocyclic group capable of forming a conjugated system with a> C═NH group.) Two

[0014]

[Chemical 6]

(Wherein A ² represents O or NH. Z is the same as in the general formula (1)) and urea are reacted in the presence of a catalyst without contacting the reaction solution with air. The method for producing an imino compound is characterized in that the reaction is performed by sealing with ammonia, and [2] a precipitate produced in the reaction system is extracted from the reaction system in a slurry state, and the slurry is solid-liquid separated to obtain a liquid. It is supplied again to the reaction system, and the solid is washed and dried to recover as compound 1, which provides the production method described in [1].

The present invention will be described in detail below. The compound 1 of the present invention has at least one or more> C = NH group in its structure. Examples of the aromatic ring group represented by Z in the formula (1) include a benzene ring, a naphthalene ring, a biphenyl ring, an anthracene ring, an indene ring, a fluorene ring, a phenanthrene ring, an acenaphthene ring, etc., and their derivatives and heterocycles. Examples of the ring group include furan ring, pyrrole ring, thiophene ring, benzofuran ring, indole ring, indazole ring, coumarone ring, benzimidazolone ring, benzothiophene ring, benzoxazole ring, benzothiazole ring, benzimidazole ring, pyridine. Ring, quinoline ring, isoquinoline ring, quinazoline ring, acridine ring,
Examples thereof include a phenazine ring, a pyrazine ring, an oxazine ring, a xanthene ring, a purine ring, a dibenzofuran ring, a dibenzopyrrole ring, an anthraquinone ring and the like and derivatives thereof. Examples of the substituent forming the derivative include a halogen atom, an alkyl group having 1 to 10 carbon atoms and 1 to 10 carbon atoms.
And alkoxy groups, phenyl groups, phenoxy groups, vinyl groups, cyano groups, ester groups, amide groups, nitro groups, sulfo groups, carboxyl groups, hydroxyl groups, amino groups, mercapto groups and alkylmercapto groups.

A in the formula (1)¹Represents O or NH
You. In the method of the present invention, first, A is used as an intermediate product.¹O is
Obtained and then the final product A¹NH gets instantly
Can be All of these compounds are useful as thermosensitive coloring materials.
Although it is a thing, as described above, A ¹NH is A¹Compared to O
It is more useful in terms of sensitivity. Such imino compounds
As azomethine pigments, especially isoindolino
Raw material for synthesizing pigments, or a partial structure of the pigment structure
Many such compounds are known. For example,
48-4601, JP-A-48-83116
Report, JP-A-49-128933, JP-A-54-8
3026, JP-A-56-109255, etc.
Has been described.

As a concrete example, for example, in the case of A ¹ O, 3
-Iminoisoindoline-1-one, 3-imino-4,
5,6,7-tetrachloroisoindoline-1-one,
3-imino-4,5,6,7-tetrabromoisoindoline-1-one, 3-imino-4,5,6,7-tetrafluoroisoindoline-1-one, 3-imino-5
6-dichloroisoindoline-1-one, 3-imino-
4,5,7-Trichloro-6-methoxy-isoindoline-1-one, 3-imino-4,5,7-trichloro-
6-methylmercapto-isoindoline-1-one, 3
-Imino-8-nitroisoindoline- ¹ -one, etc., and in the case of A ¹ NH, 1,3-diiminoisoindoline, 1,3-diimino-4,5,6,7-tetrachloroisoindoline , 1,3, diimino-6-methoxyisoindoline, 1,3-diimino-6-cyanoisoindoline, 7-amino-2,3-dimethyl-5-oxopyrrolo [3,4b] pyrazine, 7-amino-2 , 3-diphenyl-5-oxopyrrolo [3,4b] pyrazine and the like.

Compound 1 is said to have an isomer structure as shown in the following formula depending on the conditions [P. F. Clark
et al, J .; Chem. Soc. 3593 (195
3)].

[0020]

[Chemical 7]

Therefore, although the above-mentioned compound names may be expressed by different names, they are all included in compound 1. In the compound 2 used in the present invention, Z which is an aromatic ring group or a heterocyclic group
Is exactly the same as the general formula (1). A ² is O or N
Represents H. The compound in which A ² is NH is an intermediate product when the present invention is carried out using a compound in which A ² is O as a raw material.

In the present invention, the above compound 2 and urea are
Compound 1 is produced by reacting in the presence of a catalyst. At that time, it is essential to seal the reaction liquid with ammonia without contacting with air to react. As a result, compound 1 can be obtained in a high yield, and A relative to A ¹ O can be obtained.
The ratio of ¹ NH can be increased, and the imino compound can be efficiently produced without being colored. When the reaction of the present invention is carried out with the reaction liquid in contact with air, the imino compound is colored. On the other hand, when to prevent contact of the reaction solution with air by bubbling inert gas such as nitrogen, the ratio of A ¹ NH for A ¹ O is lowered. As in the present invention, the first time the reaction solution by reacting seals with ammonia without contact with air, a high ratio of A ¹ NH for A ¹ O, yet without coloring the imino compound, Compound 1 It was revealed that it can be efficiently produced with a high yield.

In the present invention, the precipitate produced in the reaction system is extracted from the reaction system in the form of a slurry, the slurry is solid-liquid separated, the liquid is supplied again to the reaction system, and the solid is washed and dried to obtain Compound 1. The method of collecting is preferable. In particular, a method of sealing with ammonia, adding compound 2 in divided portions while maintaining the two-layer state of the urea layer and the solvent layer, and performing the above operation to recover compound 1 is preferable. Compound 1 can be continuously produced by this method. This is extremely advantageous in that the equipment can be made small and the handling can be facilitated when it is carried out industrially. Further, according to this method, the compound 2 produced by the reaction can be discharged out of the system without being left in the reaction system for a long period of time, and thus the production of by-products can be suppressed.

As the ammonia used in the present invention,
Either liquid ammonia or ammonia gas can be used. The amount of ammonia is not particularly limited, but is usually 0.001 to 1000 N · per 1 liter of the reaction solution.
L / hr, preferably 0.01 to 100 N · liter / hr. In the present invention, urea is usually
An excess is used over the stoichiometric amount for producing the desired imino compound. Usually, for stoichiometric amounts,
It is in the range of 1.01 to 1000 times, preferably 1.1.
The range is up to 300 times.

The catalyst used in the present invention is not particularly limited.
But usually ammonium molybdate, molybdenum oxide
Molybdenum compounds such as, titanium chloride, boric acid, vanadium
Ammonium acid salt or the like is used. Particularly preferred is
It is a heteropoly acid in which the polyacid atom is molybdenum. F
Telopolyacid is a condensed acid composed of two or more oxygen acids.
It Hetero atoms include P, AS, Si, Ge, T
i, Ce, Th, Mn, Ni, Te, I, Co, Cr,
Fe, Ga, etc. are mentioned. Molybdic acid heteropoly
Specific examples of the acid include H₃(PMo₁₂O₄₀), H₃(A
sMo₁₂O₄₀), H _Four(SiMo₁₂O₄₀), H_Four(Ge
Mo₁₂O₄₀), H_Four(TiMo₁₂O₄₀), H ₈(CeM
o₁₂O₄₂), H₈(ThMo₁₂O₄₂), H₇(PMo₁₁
O₃₉), H₇(AsMo₁₁O₃₉), H₈(GeMo₁₁O
₃₉), H₆(MnMo₉O₃₂), H₆(NiMo
₉O₃₂), H₆(TeMo₆O_{twenty four}), H_Five(IMo₆O
_{twenty four}), H₃(CoMo₆O_{twenty four}H₆), H₃(CrMo₆
O_{twenty four}H₆), H₃(FeMo₆O_{twenty four}H ₆), H₃(Ga
Mo₆O_{twenty four}H₆), H_Four(NiMo₆O_{twenty four}H₆), H₆
(P₂Mo₁₈O₆₂), H₆(As₂Mo₁₈O₆₂) Etc.
You can

Further, a mixed coordination heteropolyacid in which two or more kinds of atoms are coordinated, such as H ₄ PMoW ₁₁ O ₄₀ and H ₄ P.
ReW ₁₁ O ₄₀ , H ₄ PVMo ₁₁ O ₄₀ , H ₅ PV ₂ Mo _{10
O 40, H 3 PMo 6 W} 6 O 40 and the like are also used. These heteropolyacids may be hydrates. All of these heteropolyacids are known. From the viewpoint of ease of synthesis or availability, P as a hetero atom is used.
Alternatively, a heteropolyacid containing Si is preferable, and in particular,
12-molybdophosphoric acid, 12-molybdosilicic acid and the like are preferable.

These catalysts may be used alone or in combination of two or more kinds. In the present invention, the reaction temperature is 1
The range of 00 to 200 ° C is preferable, and the range of 120 to 180 ° C is more preferable. The yield decreases both above and below this temperature range. There is no particular limitation on the reaction pressure,
Usually, it is carried out under normal pressure, but in order to increase the concentration of ammonia in the reaction solution and accelerate the reaction rate, it is also preferable to carry out the reaction under pressure. The reaction time varies depending on the reaction temperature, the amount of catalyst, the type of the desired imino compound, and the like, and is not particularly limited, but is usually selected in the range of about 10 minutes to 30 hours.

The reaction of the present invention can be carried out without solvent, but if necessary, it is carried out using a solvent. There is no particular limitation on the solvent used, usually, aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, chlorinated hydrocarbon solvents, alcohol solvents, ether solvents, ketone solvents, ester solvents, A nitrogen compound-based solvent or the like is used. Specific examples thereof include liquid paraffin, toluene, xylene, monochlorobenzene, dichlorobenzene, trichlorobenzene, ethyl benzoate, ethylene glycol, methyl cellosolve, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, nitrobenzene and the like.

When carrying out the reaction in the present invention, a stabilizer may be present in the reaction system, if necessary. Examples of the stabilizer include nitric acid, phosphoric acid, hydrochloric acid, methanesulfonic acid, methionic acid, p-toluenesulfonic acid, inorganic acids such as p-toluenesulfonic acid, organic acids, and ammonium salts thereof. These stabilizers are often effective in improving the yield of the desired product.

[0030]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited thereto. The quantitative analysis of the reaction product was carried out using a high performance liquid chromatograph after the reaction product was dissolved in dimethylacetamide.

[0031]

EXAMPLE 1 7.5 g of urea, 0.018 g of 12-molybdophosphoric acid 30 hydrate (0.09 mg of molybdenum), 20.0 g of nitrobenzene, and 1 ammonium nitrate were placed in a 100 ml glass four-necked flask equipped with a stirrer. 0.62 g and 1.48 g of phthalic anhydride were charged, and the mixture was heated to 150 ° C. in an oil bath and reacted. At this time, the reaction was carried out for 2 hours while blowing 1 N · liter / hr of ammonia gas into the reactor.

As a result, the conversion rate of phthalic anhydride is 100.
%Met. The yield of each reaction product was 58.0% of 1,3-diiminoisoindoline, 38.9% of 3-iminoisoindoline-1-one, and 96.9% in total, and the obtained solid was It was white. In addition, 2.0% of the intermediate phthalimide was produced. The ratio of 1,3-diiminoisoindoline to 3-iminoisoindoline-1-one was 60/40.

[0033]

[Comparative Example 1] Ammonia gas was not blown into the reactor,
The reaction was performed in exactly the same manner as in Example 1 except that the reaction was carried out by contacting with air. As a result, the conversion rate of phthalic anhydride was 100%. The yields of the respective reaction products were 1,4.8-diiminoisoindoline 44.8%, 3-iminoisoindoline-1-one 46.6%, 91.4% in total, which were lower than those in Example 1. And the obtained solid was colored brown. In addition, 3.9% of the intermediate phthalimide was produced. Also, the ratio of 1,3-diiminoisoindoline to 3-iminoisoindoline-1-one is 49/5.
1, which was a lower value than that in Example 1.

[0034]

Example 2 In a 100 ml four-neck glass flask equipped with a stirrer, 15.0 g of urea, 0.037 g of 12-molybdophosphoric acid (1.81 mg equivalent of molybdenum), 10.0 g of nitrobenzene, 1.62 g of ammonium chloride,
0.57 g of tetrachlorophthalic anhydride was charged and heated to 130 ° C. in an oil bath for reaction. At this time, the reaction was performed for 2.5 hours while blowing 1 N · liter / hr of ammonia gas into the reactor.

As a result, the conversion rate of tetrachlorophthalic anhydride was 100%. The yield of each reaction product is 1,
3-diimino-4,5,6,7-tetrachloroisoindoline 55.0%, 3-imino-4,5,6,7-tetrachloroisoindoline-1-one 39.8%, a total of 94. 8% and the obtained solid was white. In addition, 3.0% of the intermediate tetrachlorophthalimide was produced. In addition, 1,3-diimino-4,5,6,7
-Tetrachlorisoindoline and 3-imino-4,5,5
The ratio of 6,7-tetrachloroisoindoline-1-one was 58/42.

[0036]

[Comparative Example 2] Nitrogen gas in the reactor of 1 N · liter / hr
The reaction was performed in exactly the same manner as in Example 2 except that the reaction was carried out while blowing. As a result, the conversion rate of tetrachlorophthalic anhydride was 100%. The yield of each reaction product was 1,3-diimino-4,5,6,7-tetrachloroisoindoline 31.1%, 3-imino-4,5,6,6.
7-Tetrachloroisoindoline-1-one 49.7
%, 80.8% in total, and the obtained solid was colored brown green. In addition, 11.1% of the intermediate tetrachlorophthalimide was produced. The ratio of 1,3-diimino-4,5,6,7-tetrachloroisoindoline to 3-imino-4,5,6,7-tetrachloroisoindoline-1-one was 38/62. .

[0037]

Example 3 Urea 1056 g, 12-in a 1000 ml jacketed glass reactor equipped with a stirrer
Molybdophosphoric acid 30 hydrate 9.9 g (molybdenum 47.
8 mg equivalent), 176 g of nitrobenzene, and 42.9 g of ammonium chloride were charged, and 130 by heating oil circulation.
After heating to ℃, tetrachlorophthalic anhydride 3.02
g was added every hour, and a total of 302 g was reacted. At this time, 1N · liter / h of ammonia gas was placed in the reactor.
While bubbling r, the reaction was carried out by further stirring so as not to destroy the separated state of the nitrobenzene layer and the urea layer.
After 7 hours of reaction, the precipitate formed in the reaction system was slurried.
In this state, the slurry was taken out of the reaction system, the slurry was subjected to solid-liquid separation, the liquid was supplied again to the reaction system, and the solid was washed, dried and recovered, and the reaction was carried out for 100 hours.

As a result, the conversion rate of tetrachlorophthalic anhydride was 100%. The yield of each reaction product is 1,
3-diimino-4,5,6,7-tetrachloroisoindoline 80.7%, 3-imino-4,5,6,7-tetrachloroisoindoline-1-one 15.5%, 96. It was 2%. In addition, 2.5% of the intermediate tetrachlorophthalimide was produced. Also, 1,3-
The ratio of diimino-4,5,6,7-tetrachloroisoindoline to 3-imino-4,5,6,7-tetrachloroisoindoline-1-one was 84/16. The obtained solid was 289 g and was white. The ratio in the solid is 1,3-diimino-4,5,6,7-tetrachloroisoindoline 81.3 wt%, 3-imino-4,5,5.
6,7-Tetrachloroisoindoline-1-one 14.
The content was 7 wt%, tetrachlorophthalimide 2.0 wt%, and other unknown components 2.0 wt%. 1,3-Diimino-4,5,6,7-tetrachloroisoindoline and 3-
The ratio of imino-4,5,6,7-tetrachloroisoindoline-1-one was 85/15.

[0039]

INDUSTRIAL APPLICABILITY According to the present invention, an imino compound useful as a pigment intermediate or a thermosensitive coloring material can be produced as a solid without coloring in a high yield by a simple process without using a difficult-to-handle reactant. it can.

Claims (2)

[Claims] 1. The following general formula (1): (In the formula, A ¹ represents O or NH, and Z represents an aromatic ring group or a heterocyclic group capable of forming a conjugated system with a> C═NH group.) , The following general formula (2): (In the formula, A ² represents O or NH. Z represents the general formula (1).
Same as. ), When reacting the compound represented by the formula (1) with urea in the presence of a catalyst, the reaction solution is sealed with ammonia and allowed to react without contacting with air, and the reaction is carried out. 2. The precipitate formed in the reaction system is extracted from the reaction system in a slurry state, the slurry is separated into solid and liquid, the liquid is supplied to the reaction system again, and the solid is washed and dried to obtain the compound represented by the general formula (1). The method according to claim 1, which is recovered as an imino compound represented by: