JPH111465A - Production of tropolone derivative - Google Patents

Abstract

PROBLEM TO BE SOLVED: To readily produce the highly pure subject compound in a high yield by forming tropolones from a raw material and further subjecting the tropolones to a sulfonylation reaction without isolating the tropolones. SOLUTION: (A) A compound of formula I [R<1> -R<5> are each independently H, a halogen or an aliphatic or an aromatic hydrocarbon group (having a substituent); X<1> and X<2> are each a halogen independently] is heated in a carboxylic acid solvent containing a carboxylic acid salt of an acid binder to provide (B) tropolones of formula II, and the component B is further reacted with a sulfonylation agent (e.g. sulfonyl halide) without isolating the component B to provide sulfonyloxytropolones of formula III [R<6> is an aliphatic or an aromatic hydrocarbon group (having a substituent)] in the method for producing tropolone derivative. 7,7-dichlorobicyclo[3.2.0]hept-2-en-6-one, etc., are exemplified as the component A. By the method, a raw material for an azulene derivative is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a raw material for synthesizing an azulene derivative useful as a laser absorbing dye, a liquid crystal element, an optical recording material such as an electrophotographic photosensitive member, an organic conductor, a catalyst ligand, a drug, a dye and the like. The present invention relates to a production method suitable for industrial production of sulfonyloxytropones.

[0002]

2. Description of the Related Art Tropon derivatives having a substituent at the 2-position are important synthetic intermediates for various fine chemicals, and a simple and suitable production method for industrial production is demanded. Among them, sulfonyloxytropones are the most important intermediates, and are generally produced by reacting tropolone with a sulfonylating agent. Tropolones are described in Org. Synth. , Coll. Vol. 4,
As described in US Pat. No. 1037 (1963), the compound of formula (1), which is a precursor, is formed by heating in a carboxylic acid solvent such as acetic acid in the presence of a salt of an acid binder such as sodium acetate. .

[0003]

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[0004] The tropolone formed can be isolated from the carboxylic acid solvent by extraction with an organic solvent, followed by distillation under reduced pressure.

[0005]

However, according to the study of the present inventors, tropolone has a phenolic hydroxyl group and thus is easily oxidized and thermally decomposed.
Its isolation is quite difficult. For example, tropolone is 13
Since thermal decomposition occurs at about 0 ° C., if distillation is performed at 110 ° C., the pressure must be reduced to about 10 mmHg, which is not suitable for industrial purification. Further, instead of distillation purification, an attempt was made to add a poor solvent to the extract to cause crystallization, but no suitable poor solvent was found. Accordingly, an object of the present invention is to provide a method for producing sulfonyloxytropones via tropolones, which avoids the difficulties involved in isolating tropolones.

[0006]

According to the present invention, the following formula (1) is provided.

[0007]

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[0008] (wherein, R ¹ to R ⁵ each independently represent a hydrogen atom, a halogen atom or an optionally substituted aliphatic or aromatic hydrocarbon group. Provided that R ¹ to R
⁵ may be arbitrarily bonded to form a ring. X ¹ and X ² each independently represent a halogen atom. ) Is heated in a carboxylic acid solvent containing a carboxylic acid salt of an acid binder to obtain a compound represented by the following formula (2):

[0009]

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(Wherein R ^{1 to} R ⁵ are the same as above), tropolone is extracted with an organic solvent, and the tropolone is isolated from the obtained extract. The sulfonyloxytropones represented by the following formula (3) can be produced in high yield by reacting this with a sulfonylating agent without performing the reaction.

[0011]

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(Wherein, R ^{1 to} R ⁵ are the same as described above;
R ⁶ represents an aliphatic or aromatic hydrocarbon group which may have a substituent)

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Formula (1) which is a raw material of the method of the present invention
In the compound of the formula ( ¹⁾ , R ^{1 to} R ⁵ are essentially sites not participating in the reaction, and may be any substituents as long as they are inert to the reaction. Examples of the halogen atom represented by R ^{1 to} R ⁵ and X ¹ and X ² include a chlorine atom or a bromine atom.
As the aliphatic hydrocarbon group represented by R ^{1 to} R ⁵ , a methyl group,
Examples thereof include lower alkyl groups having about 1 to 5 carbon atoms such as an ethyl group and an i-propyl group, and examples of the aromatic hydrocarbon group include a phenyl group and a p-tolyl group. In addition, a halogen atom, an alkoxy group, or the like, such as a methoxymethyl group, a trifluoromethyl group, a p-chlorophenyl group, or a p-ethoxyphenyl group, may be bonded to these. Further, R _{1 to} R ⁵ may be arbitrarily bonded to form a ring. Examples of such a ring include a carbon ring formed by bonding two adjacent Rs, for example, a benzene ring. Further, R adjacent to a carbon atom on the carbon ring may be further bonded to form a ring. These rings are usually 4- to 6-membered rings. Some examples of the compound represented by the formula (1) include 7,7-dichlorobicyclo [3.
2.0] Hept-2-en-6-one, 7,7-dichloro-2,3-benzobicyclo [3.2.0] -6-heptanone, 3-isopropyl-7,7-dichlorobicyclo [3 .2.0] hept-2-en-6-one and the like.

As a reaction solvent for converting the compound of the formula (1) into the tropone derivative of the formula (2), lower carboxylic acids such as acetic acid and propionic acid are used. The carboxylic acid solvent is generally used in a molar amount of 5 to 100 times, preferably 10 to 50 times the compound of the formula (1). The carboxylic acid solvent contains water in an amount of at least equimolar to the compound of the formula (1). The amount of water in the carboxylic acid solvent is usually 1 to 100 times the molar amount of the compound of the formula (1).

The carboxylic acid solvent contains an acid binder which captures a halogen by-produced from the compound of the formula (1). Examples of the acid binder include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, ammonia, and triethylamine. Since the acid binder exists as a carboxylate in the carboxylic acid solvent, the carboxylate may be used instead of using a free acid binder. The acid binder is usually used in an amount of 2 to 2 with respect to the compound of the formula (1).
It is used in a molar amount of 10 times, preferably 4 to 7 times. The reaction is preferably carried out under normal pressure around the boiling point of the carboxylic acid solvent in view of the reaction rate and operability. The time required for the reaction is usually 1 to 20 hours.

After completion of the reaction, the tropolone of the formula (2) formed by extracting the reaction solution with an organic solvent is separated from the reaction solution. Usually, it is preferable to add hydrochloric acid or the like to the reaction solution to convert the unreacted acid binder into a neutral salt and then perform extraction. Examples of the organic solvent used for the extraction include aromatic hydrocarbons such as toluene and xylene, ethers such as dibutyl ether and diethyl ether, and halogenated hydrocarbons such as dichloromethane, chloroform and chlorobenzene.

The extract containing the tropolone of the formula (2)
From there, the tropolone is used for the next reaction with a sulfonylating agent without isolation. Usually, it is preferable that the extract is concentrated to increase the concentration of the tropolone of the formula (2) and then subjected to the sulfonylation reaction. The degree of concentration is arbitrary, and if desired, the tropolone of the formula (2) may be partially precipitated. Further, if desired, another solvent may be added to the concentrated solution to be subjected to a sulfonylation reaction. In any case, the concentration of the tropolone in the solution subjected to the sulfonylation reaction is preferably 1 to 50% by weight, particularly preferably about 1 to 20% by weight. As the sulfonylating agent used for sulfonylation of the tropolone of the formula (2), one represented by the following formula (4) or (5) is usually used.

[0018]

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(Wherein, R ⁶ represents an aliphatic or aromatic hydrocarbon group which may have a substituent, and R ⁷ represents a halogen atom or an alkoxy group or an aryloxy group which may have a substituent. Shown.)

In the formulas (4) and (5), examples of the aliphatic hydrocarbon group represented by R ⁶ include a lower alkyl group having 1 to 5 carbon atoms such as a methyl group, an ethyl group and an i-propyl group. Examples of the hydrocarbon group include a phenyl group, an o-tolyl group, and a p-tolyl group. Further, an alkoxy group or a halogen atom such as a methoxymethyl group, a p-methoxyphenyl group, a trifluoromethyl group, or a p-fluorophenyl group may be bonded to these.
Examples of the halogen atom represented by R ⁷ include a chlorine atom and a bromine atom. Examples of the alkoxy group and the aryloxy group represented by R ⁷ include a lower alkoxy group having 1 to 5 carbon atoms such as a methoxy group, an ethoxy group, an i-propyloxy group, a phenoxy group, an o-tolyloxy group, and a p-tolyloxy group. Can be Further, an alkoxy group or a halogen atom such as a methoxyethoxy group, a p-methoxyphenoxy group, a trifluoromethoxy group, or a p-fluorophenoxy group may be bonded to these.

Among the sulfonylating agents represented by the formulas (4) and (5), those usually used are exemplified by p-toluenesulfonyl chloride, trifluoromethanesulfonyl chloride, methyl p-toluenesulfonate, p-toluenesulfonate Acid anhydride, trifluoromethanesulfonic anhydride and the like can be mentioned. The sulfonylating agent is used in an amount of usually 0.9 to 10 times, preferably 1.0 to 1.2 times, the mole of the tropolone of the formula (2).

When an acid is by-produced by the reaction with the sulfonylating agent, an acid binder is present in the reaction system to capture the by-produced acid. As the acid binder, it is preferable to use a tertiary amine soluble in the reaction system. For example, triethylamine, trimethylamine, N, N-dimethylaniline,
N, N-diethylaniline, pyridine and the like are used.
The acid binder is used in an amount of usually 1 to 30 times, preferably 1 to 3 times the mole of the by-produced acid. If desired, a large amount of a tertiary amine can be used also as a part of the solvent. In this case, the extract is concentrated to an appropriate concentration and then mixed with a tertiary amine in an amount of the solvent to form a sulfonylation. The reaction may be performed.

The reaction temperature is usually from -50 ° C to 100 ° C, preferably from 0 to 50 ° C. When the temperature is low, a long time is required for the reaction, and when the temperature is high, a side reaction is likely to occur. The reaction time depends on conditions such as temperature, but is usually 1 to 20 hours, and it is preferable to end the reaction in 2 to 5 hours. The reaction pressure may be a pressure at which the solvent maintains a liquid phase, and the reaction is usually performed at normal pressure. After completion of the reaction, water is added to the reaction solution to decompose the unreacted sulfonylating agent, and then filtered to obtain the generated sulfonyloxytropones.

[0024]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the examples unless it exceeds the gist.

Example 1 825 ml of acetic acid was added to 3
90 to 1 in a liter separable flask
Heated to 00 ° C. After adding and dissolving 210 g of sodium hydroxide, 7,7-dichlorobicyclo [3.
2.0] Hept-2-en-6-one (185.1 g) was added, and the mixture was reacted under heating and refluxing for 8 hours. After cooling to 55 ° C., 361 g of 35% hydrochloric acid was added, and then 1.5 liter of toluene was added, followed by stirring for 30 minutes. The reaction solution was filtered and the residue was washed three times with 200 ml of toluene. The washing solution and the filtrate were combined and separated into an aqueous phase and a toluene phase.

Further, the aqueous phase was extracted three times with 1 liter of toluene, and this toluene phase was combined with the toluene phase obtained above. 119.8 g of tropolone was contained in this toluene solution.
(0.981 mol, 93.4% yield). The tropolone concentration is about 15% by weight.
After concentrating until the mixture became, 203.9 g of p-toluenesulfonyl chloride was added. 20 to 3
At 0 ° C., 119.1 g of triethylamine was added dropwise over 30 minutes.
It was kept at 0 ° C. After adding 1.44 liters of water and stirring for 1 hour, the precipitated crystals were collected by filtration. The crystals were washed twice with 620 ml of water, dried, and 230.4 g of 2- (p-toluenesulfonyloxy) tropone (0.
834 mol, yield 85.0%, purity 99.3%). ¹ H-NMR spectrum (CDCl ₃ , 400 MHz,
δ / ppm) 2.43 (s, CH 3, 3H), 6.94~7.22
(M, CH, 4H), 7.45 (d, J = 8 Hz, C
H, 2H), 7.43 to 7.46 (m, CH, 3H),
7.91 (d, J = 8 Hz, CH, 2H) m. p. 157-158 ° C From the results, it can be seen that the target sulfonyloxytropones were obtained in high purity and high yield without isolating the tropolone on the way.

[0027]

According to the present invention, tropolone, which is unstable and difficult to handle and difficult to produce industrially, is subjected to a sulfonylation reaction without isolation. Highly pure sulfonyloxytropones can be produced in high yield.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takeshi Ken Uegami 1-1 Kurosaki Castle Stone, Yawatanishi-ku, Kitakyushu City Inside Mitsubishi Chemical Corporation Kurosaki Office

Claims (6)

[Claims] [Claim 1] The following formula (1) (Wherein, R ^{1 to} R ⁵ are each independently a hydrogen atom,
It represents a halogen atom or an aliphatic or aromatic hydrocarbon group which may have a substituent. However, R ^{1 to} R ⁵ may be arbitrarily bonded to form a ring. X ¹ and X ² each independently represent a halogen atom. ) Is heated in a carboxylic acid solvent containing a carboxylic acid salt of an acid binder to give a compound of the following formula (2): (Wherein, R ^{1 to} R ⁵ are the same as described above), and the formed tropolone is extracted with an organic solvent, and without isolating the tropolone from the obtained extract. A method for producing a tropone derivative, characterized by reacting the compound with a sulfonylating agent to produce a sulfonyloxytropone represented by the following formula (3). Embedded image (In the formula, R ^{1 to} R ⁵ are the same as described above, and R ⁶ represents an aliphatic or aromatic hydrocarbon group which may have a substituent.) 2. The method for producing a tropone derivative according to claim 1, wherein R ⁶ is a p-tolyl group. 3. R ^{1 to} R ⁵ are all hydrogen atoms,
^{3. The} method for producing a tropone derivative according to claim ^1, wherein X ¹ and X ² are both chlorine atoms. 4. The method for producing a tropone derivative according to claim 1, wherein the organic solvent used for the extraction is a hydrocarbon or a halogenated hydrocarbon solvent. 5. The process for producing a tropone derivative according to claim 1, wherein the extract containing the tropone derivative is concentrated and then subjected to a reaction with a sulfonylating agent. 6. The process for producing a tropone derivative according to claim 1, wherein a sulfonylation reaction is carried out in the presence of an acid binder, using a sulfonyl halide as a sulfonylating agent.