JPH05140130A - Production of 5-benzylideneoxazolidine-2,4-dione derivative - Google Patents

Abstract

PURPOSE:To obtain the subject compound in high yield by passing 2-thioxo-4- oxazolidinones through 5-benzylidene-2-thioxo-4-oxazolidinones and 5- benzylidene-2-alkylthio-oxazolidin-4-ones. CONSTITUTION:A 2-thioxo-4-oxazolidinone derivative expressed by formula II (Ar is aryl; R is H, alkyl or aryl) is made to react with an aromatic aldehyde expressed by the formula Ar-CHO to provide a 5-benzylidene-2-thioxo-4- oxazolidinone derivative expressed by formula III, which is then reacted with an alkyl halide expressed by the formula R'X (R' is alkyl; X is Cl, Br or I) to afford a compound expressed by formula V when R is H and a compound expressed by formula IV when R is other than H. The resultant compound is finally reacted with an acid to provide a 5-benzylideneoxazolidine-2,4-dione derivative expressed by formula I. The various 5-benzylideneoxazolidine-2,4-dione derivatives are obtained in high yield by this method. The resultant compounds are useful as functional compounds, etc., such as a dye for photosensitive materials or organic nonlinear optical materials.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for synthesizing a 5-benzylidene oxazolidine-2,4-dione derivative, more specifically, a 5-benzylidene oxazolidine-2 derivative using a 2-thioxo-4-oxazolidinone derivative. The present invention relates to a method for producing a 1,4-dione derivative.

[0002]

BACKGROUND OF THE INVENTION 5-Benzylideneoxazolidine-2,
The 4-dione derivative itself is used as a functional compound such as a dye for a light-sensitive material or an organic nonlinear optical material,
It is useful as an intermediate for many organic compounds.

Such a 5-benzylidene oxazolidine-2,4-dione derivative is a heterocyclic compound having an active methylene and an aromatic aldehyde which are commonly used in the synthesis of 5-benzylidene azolidine-2,4-dione derivatives. The dehydration condensation reaction with and gives only a very low yield.

For example, 3-methyloxazolidine-2,
By dehydration condensation of 4-dione and p-anisaldehyde,
When the following compounds were synthesized, the yield was 7%, which was extremely low.

[0005]

[Chemical 4]

Further, in particular, when the N-position is unsubstituted, it is more difficult to synthesize. For example, an attempt was made to synthesize the following compound by dehydration condensation of oxazolidine-2,4-dione and p-anisaldehyde, but the raw material was recovered.

[0007]

[Chemical 5]

Also, as a past synthesis example, Japanese Patent Laid-Open No. 62-62
Only the compound described in No. 29570 is known.

[0009]

[Chemical 6]

However, this method has a very low yield.

[0011] Furthermore, SN Baranofu (SNBarano
v), ID Komaritsa, Kimiya Getello Tsiklischeski Sordini (Khi
M. Geterotsikl. Soedin.), Vol. 1, p. 69 (1965)
(Year) states that oxazolidine-2,4-dione and benzaldehyde do not react.

[0012]

[Chemical 7]

Such an oxazolidine-2,4-dione has very low reactivity.

[0014]

Therefore, such a problem
It has been desired to develop a method capable of synthesizing a -benzylidene oxazolidine-2,4-dione derivative in a high yield.

[0015]

DISCLOSURE OF THE INVENTION As a result of intensive studies conducted by the present inventors to overcome the above-mentioned drawbacks of the conventional method, the 2-thioxo-4-oxazolidinone derivative represented by the following general formula (II) is obtained. , And an aromatic aldehyde as starting materials, a 5-benzylidene-2-thioxo-4-oxazolidinone derivative represented by the following general formula (III) and a 5-benzylidene-2- represented by the following general formula (IV).
It was found that a 5-benzylidene oxazolidine-2,4-dione derivative represented by the following general formula (I) can be synthesized by the following route using an alkylthiooxazolin-4-one derivative as an intermediate.

[0016]

[Chemical 8]

That is, according to the present invention, in producing a 5-benzylideneoxazolidine-2,4-dione derivative represented by the following general formula (I), 2-thioxo-4-oxazolidinone represented by the following general formula (II) is produced. A derivative and an aromatic aldehyde represented by the following general formula (III)
A method for producing a 5-benzylidene oxazolidine-2,4-dione derivative, which comprises reacting an alkyl halide with a benzylidene-2-thioxo-4-oxazolidinone derivative and then treating with an acid. General formula (I)

[0018]

[Chemical 9]

General formula (II)

[0020]

[Chemical 10]

General formula (III)

[0022]

[Chemical 11]

Next, the above general formulas (I), (II), (III),
Ar, R, and R'in the compound represented by (IV) will be described in more detail.

Ar represents an aryl group having 20 or less carbon atoms. For example, phenyl group, naphthyl group, and alkyl group, alkoxy group, aryl group, aryloxy group, alkylthio group, arylthio group, cyano group, formyl group, fluoroalkyl group, acyl group, carboxyl group,
Examples include alkoxycarbonyl group, amino group, alkylamino group, acylamino group, nitro group, hydroxy group, acyloxy group, alkylsulfinyl group, alkylsulfonyl group, carbamoyl group, sulfamoyl group, phenyl group substituted with halogen atom, and naphthyl group. Be done.

R represents an alkyl group having 10 or less carbon atoms, an aryl group or a hydrogen atom. Examples thereof include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a cyclohexyl group, a benzyl group and a phenyl group.

R'represents an alkyl group having 6 or less carbon atoms, particularly preferably a methyl group or an ethyl group.

Specific examples of the production method of the present invention include the following methods.

[0028]

[Chemical 12]

This will be described in detail.

(I) Synthesis of Compound (III) The compound (III) can be easily synthesized by dehydration condensation of the compound (II) and an aromatic aldehyde. As the solvent, alcohols, ethers, nitrites, amides and the like can be used, and as the catalyst, acid and base can be used. The acid may be any of organic acids such as acetic acid and tosylic acid, and inorganic acids such as hydrochloric acid and sulfuric acid. As the base, pyridine, triethylamine,
Organic bases such as 1,8-diazabicyclo [5,4,0] -7-undecene (DBU), inorganic bases such as potassium carbonate, sodium hydrogen carbonate, potassium t-butoxide, sodium hydride and sodium hydroxide. Any of The reaction temperature may be -100 ° C to 150 ° C, preferably 25 to 100 ° C.

(Ii) Synthesis of compound (IV) R'X is 1 to 1 with respect to the compound represented by the general formula (III).
It is preferable to carry out the reaction using 1.5 molar equivalents, and it is more preferable to carry out the reaction using 1 to 1.2 molar equivalents. When R'X is less than 1 molar equivalent, the yield is remarkably reduced, and when it exceeds 1.5 molar equivalent, the production of by-products is increased.

As the base used in the reaction, pyridine, triethylamine, 1,8-diazabicyclo [5,4,4]
0] -7-undecene (DBU), an organic base such as potassium carbonate, sodium hydrogencarbonate, potassium-t-butoxide, sodium hydride, or sodium hydroxide.

Examples of the solvent used in the reaction include alcohols such as methanol, ethanol and isopropanol, hydrocarbons such as n-hexane, tetrahydrofuran, ethers such as 1,2-dimethoxyethane, N,
An amide such as N-dimethylformamide, N-methylpyrrolidone, a sulfur-containing compound such as dimethyl sulfoxide and sulfolane, a nitrile such as acetonitrile, an ester such as ethyl acetate and the like are used. Of these, amides, sulfur-containing compounds and nitriles are preferable. Further, one or more kinds can be used in consideration of reaction conditions, boiling point, solubility, reactivity, odor, price and the like.

The reaction temperature is preferably 0 to 100 ° C., more preferably 10 to 50 ° C. If the temperature is less than 0 ° C., the reaction proceeds slowly and it is difficult to completely eliminate the raw materials. If the temperature exceeds ℃, the yield will be low due to the formation of by-products. The reaction is preferably carried out with appropriate stirring.

(Iii) Synthesis of Compound (I) Compound (I) can be synthesized by acid hydrolysis of compound (IV).

The acid used in the reaction may be an organic acid such as acetic acid or tosylic acid, or an inorganic acid such as hydrochloric acid or sulfuric acid.

Examples of the solvent used in the reaction include water, alcohols (eg, methanol, ethanol, isopropyl alcohol, etc.), acetonitrile, etc. One or more solvents in consideration of reaction conditions, boiling point, reactivity, odor, price, etc. Can be used.

The reaction temperature is preferably 20 to 100 ° C, more preferably 40 to 60 ° C, and the temperature is 20 ° C.
If it is less than 100 ° C, the reaction proceeds slowly and it is difficult to completely eliminate the raw materials. If it exceeds 100 ° C, a byproduct is produced, resulting in a low yield. The reaction is preferably carried out with appropriate stirring.

Next, specific examples of the compound represented by formula (I) synthesized according to the present invention will be shown, but the scope of the present invention is not limited to these.

[0040]

[Chemical 13]

[0041]

[Chemical 14]

[0042]

[Chemical 15]

[0043]

[Chemical 16]

[0044]

[Chemical 17]

[0045]

[Chemical 18]

[0046]

[Chemical 19]

[0047]

[Chemical 20]

[0048]

[Chemical 21]

[0049]

The present invention will be described in more detail based on the following examples, but the invention is not limited to the following examples without departing from the gist of the invention.

Example 1 <Synthesis of Compound 2> (i) 5- (4-methoxybenzylidene) thiazolidine-
Synthesis of 2,4-dione 20.4 g (0.15 mol) of p-anisaldehyde, 2-
17.4 g (0.15 mol) of thioxooxazolidinone,
Acetic acid 8.7 mol (0.15 mol), ammonium acetate 11.
180 ml of acetonitrile was added to 7 g (0.15 mol) of 2
Heated to reflux for hours. After cooling to room temperature, the reaction solution was poured into 1 liter of water, the precipitated crude crystals were collected by filtration, and recrystallized with methanol to obtain the desired product. Yield 9.5g (27% yield)

(Ii) 5- (4-methoxybenzylidene)-
Synthesis of 2-methylthiooxazolin-4-one 9.5 g (0.04 mol) of 5- (4-methoxybenzylidene) thiazolidine-2,4-dione and 5.5 g (0.04 mol) of potassium carbonate were added with 100 ml of acetonitrile. , 5.7 g of methyl iodide with stirring at room temperature
(0.04 mol) was added dropwise, and the mixture was further stirred at room temperature for 30 minutes. After the reaction was completed, the reaction mixture was poured into 1 liter of water, and the precipitated crude crystals were collected by filtration and recrystallized from isopropanol to obtain the desired product. Yield 10g (100% yield)

(Iii) Synthesis of Compound 2 5 g (0.02 mol) of 5- (4-methoxybenzylidene) -2-methylthiooxazolidin-4-one above was mixed with 1
75 ml of 2% hydrochloric acid was added and the mixture was heated with stirring at 50 ° C. for 30 minutes.
After the reaction was completed, the precipitated crystals were collected by filtration, purified by a silica gel column (eluent: ethyl acetate / n-hexane = 1/1), and recrystallized from isopropanol to obtain the desired product. Yield 2.9 g (yield 66%), melting point 229 ° C. ¹ H-NMR.

[0053]

[Chemical formula 22]

Δppm, Jin Hz (DMSO-d ⁶ ) 3.8 (S, 3H, OCH ₃ ) 6.7 (S, 1H, -CH =) 7.05 (d, J = 10, 2H, 3,4-H) 7.75 ( d, J = 10, 2H, 1,2-H) 12.35 (br, 1H, NH) UV-spectrum (in ethanol) λmax = 324nm

Since compound 2 has an absorption maximum at 324 nm, it is useful as a UV absorber.

Example 2 Synthesis of <Compound 5> (i) Synthesis of 5- (3,4-dimethoxybenzylidene) thiazolidine-2,4-dione 3,3.2-dimethoxybenzaldehyde 33.2 g (0.
2 mol), 2-thioxooxazolidinone 23.4 g
(0.2 mol) and piperidine (1.7 g, 0.02 mol) were added with 400 ml of ethanol and heated under reflux for 2 hours. After cooling to room temperature, the reaction solution was poured into 1 liter of water, the precipitated crude crystals were collected by filtration, and recrystallized with methanol to obtain the desired product. Yield 15.8g (Yield 30%)

(Ii) Synthesis of 5- (3,4-dimethoxybenzylidene) -2-methylthiooxazoline-4-one 15.8 g (5- (3,4-dimethoxybenzylidene) thiozolidine-2,4-dione above 0.06 mol), 8.2 g (0.06 mol) of potassium carbonate and 1 part of acetonitrile
Add 50 ml and stir at room temperature with methyl iodide 1
0.2 g (0.072 mol) was added dropwise, and further 3 at room temperature.
Stir for 0 minutes. After the reaction was completed, the reaction mixture was poured into 1 liter of water, and the precipitated crystals were collected by filtration and recrystallized with acetone to obtain the desired product. Yield 9.4g (yield 56%)

(Iii) Synthesis of compound 5 5- (3,4-methoxybenzylidene) -2-methylthiooxazolidin-4-one (9.4 g, 0.03)
To 8 mol), 130 ml of 12% hydrochloric acid was added, and the mixture was heated with stirring at 50 ° C. for 30 minutes. After the reaction was completed, the precipitated crystals were collected by filtration, and N,
Recrystallization was performed twice with N-dimethylformamide to obtain the desired product. Yield 2.4 g (yield 25%), melting point 288.5 ° C. ¹ H-NMR

[0059]

[Chemical formula 23]

Δppm, Jin Hz (DMSO-d ⁶ ) 3.8 (S, 3H, -OCH ₃ ) 3.82 (S, 3H, -OCH ₃ ) 6.7 (S, 1H, -CH =) 7.1 (d, J = 10 , 1H, 1-H) 7.39 (S, 1H, 2-H) 7.4 (d, J = 10, 1H, 3-H) 12.35 (br, 1H, NH) UV-spectrum (in ethanol) λmax = 339nm

Since compound 5 has an absorption maximum at 339 nm, it is useful as a UV absorber.

Example 3 <Synthesis of Compound 7> (i) Synthesis of 5- (3,4-methylenedioxybenzylidene) thiazolidine-2,4-dione Piperonal 23.8 g (0.159 mol), 2-thioxo 18.6 g (0.159 mol) of oxazolidinone, 1.4 g (0.016 mol) of piperidine and 300 ml of ethanol
Was added and the mixture was heated under reflux for 2 hours. After cooling to room temperature, the reaction solution was poured into 1 liter of water, the precipitated crude crystals were collected by filtration, and recrystallized with methanol to obtain the desired product. Yield 14.8 g (yield 40%)

(Ii) Synthesis of 5- (3,4-dimethoxybenzylidene) -2-methylthiooxazolin-4-one 5- (3,4-methylenedioxybenzylidene)
14.8 g (0.059) of thiozolidine-2,4-dione
mol) and 8.2 g (0.059 mol) of potassium carbonate, 150 ml of acetonitrile was added, 10.1 g (0.071 mol) of methyl iodide was added dropwise with stirring at room temperature, and the mixture was further stirred at room temperature for 30 minutes. After completion of the reaction, the reaction mixture was poured into 1 liter of water, the precipitated crystals were collected by filtration and recrystallized from isopropanol to obtain the desired product. Yield 9.6g (61% yield)

(Iii) Synthesis of compound 7 5- (3,4-methylenedioxybenzylidene) above
-2-Methylthiooxazolidin-4-one 9.6g
130 ml of 12% hydrochloric acid was added to (0.036 mol) and the mixture was heated and stirred at 50 ° C. for 30 minutes. After the reaction was completed, the precipitated crystals were collected by filtration and recrystallized with isopropanol to obtain the desired product. Yield 2.4 g (yield 27%), melting point 265.6 ° C. ¹ H-NMR

[0065]

[Chemical formula 24]

Δppm, Jin Hz (DMSO-d ⁶ ) 6.1 (S, 2H, -OCH ₂ O-) 7.05 (d, J = 10, 1H, 3-H) 7.35 (S, 1H, 2-H) 7.38 (d, J = 10, 1-H) 12.35 (br, 1H, NH) UV-spectrum (in ethanol) λmax = 340nm

Since compound 7 has an absorption maximum at 340 nm, it is useful as a UV absorber.

Comparative Example <Trial of Synthesis of Compound 2 by Normal Dehydration Condensation Reaction> p
-Anisaldehyde 1.4 g (0.01 mol), oxazolidine-2,4-dione 1.0 g (0.01 mol), acetic acid 0.6 ml (0.01 mol), ammonium acetate 0.8
Acetonitrile (20 ml) was added to (0.01 mol) and the mixture was heated under reflux for 12 hours.

[0069]

According to the present invention, various 5-benzylidene oxazolidine-2,4-dione derivatives can be obtained in high yield.

The usefulness of the 5-benzylideneoxazolidine-2,4-dione derivative obtained by the present invention is that it can be used as a functional compound such as a dye for a light-sensitive material and an organic nonlinear optical material, and an intermediate of many organic compounds. , It can be a raw material.

According to the present invention, it becomes possible to synthesize various 5-benzylidene oxazolidine-2,4-dione derivatives relatively freely, so that the characteristics (eg wavelength, storage stability) of the above compounds can be controlled over a wide range. It became possible to do.

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[Procedure amendment]

[Submission date] January 23, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 2

[Correction method] Change

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[Procedure Amendment 2]

[Document name to be amended] Statement

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[Correction method] Change

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Thus, oxazolidine-2,4-dione has very low reactivity.

[Procedure 3]

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[0016]

[Chemical 8] (In the formula, R'represents an alkyl group. X represents a chlorine atom, a bromine atom and an iodine atom.)

[Procedure amendment 4]

[Document name to be amended] Statement

[Name of item to be corrected] 0025

[Correction method] Change

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R represents an alkyl group having 10 or less carbon atoms, an aryl group and a hydrogen atom. For example, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group,
Examples thereof include a cyclohexyl group, a benzyl group and a phenyl group.

[Procedure Amendment 5]

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[Correction target item name] 0028

[Correction method] Change

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[0028]

[Chemical 12] (In the formula, R'represents an alkyl group. X represents a chlorine atom, a bromine atom and an iodine atom.)

[Procedure correction 6]

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[Chemical 14]

[Procedure Amendment 7]

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Example 1 <Synthesis of Compound 2> (i) Synthesis of 5- (4-methoxybenzylidene) -2-thioxo-4-oxazolidinone 20.4 g (0.15 mol) of p-anisaldehyde,
17.4 g of 2-thioxo-4-oxazolidinone (0.
15 mol), acetic acid 8.7 mol (0.15 mol),
180 ml of acetonitrile was added to 11.7 g (0.15 mol) of ammonium acetate, and the mixture was heated under reflux for 2 hours. After cooling to room temperature, the reaction solution was poured into 1 liter of water, the precipitated crude crystals were collected by filtration, and recrystallized with methanol to obtain the desired product. Yield 9.5g (27% yield)

[Procedure Amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0051

[Correction method] Change

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(Ii) Synthesis of 5- (4-methoxybenzylidene) -2-methylthiooxazolin-4-one 9.5 g (0.04mo) of 5- (4-methoxybenzylidene) -2-thioxo-4-oxazolidinone
l) and 100 g of acetonitrile to 5.5 g (0.04 mol) of potassium carbonate, 5.7 g (0.04 mol) of methyl iodide was added dropwise with stirring at room temperature, and the mixture was further stirred at room temperature for 30 minutes. After the reaction was completed, the reaction mixture was poured into 1 liter of water, and the precipitated crude crystals were collected by filtration and recrystallized from isopropanol to obtain the desired product. Yield 10g (100% yield)

[Procedure Amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0052

[Correction method] Change

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(Iii) Synthesis of Compound 2 To 5 g (0.02 mol) of 5- (4-methoxybenzylidene) -2-methylthiooxazolin-4-one described above was added 75 ml of 12% hydrochloric acid, and the mixture was heated with stirring at 50 ° C. for 30 minutes. did. After the reaction was completed, the precipitated crystals were collected by filtration, purified by a silica gel column (eluent: ethyl acetate / n-hexane = 1/1), and recrystallized from isopropanol to obtain the desired product. Yield 2.9 g (yield 66%), melting point 229 ° C. ¹ H-NMR.

[Procedure Amendment 10]

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[Correction target item name] 0056

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Example 2 Synthesis of <Compound 5> (i) 5- (3,4-dimethoxybenzylidene) -2-
Synthesis of Thioxo-4-oxazolidinone 33.2 g (0.
2 mol), 2-thioxo-4-oxazolidinone 2
3.4 g (0.2 mol), piperidine 1.7 g (0.
(02 mol) was added with 400 ml of ethanol and heated under reflux for 2 hours. After cooling to room temperature, the reaction solution was poured into 1 liter of water, the precipitated crude crystals were collected by filtration, and recrystallized with methanol to obtain the desired product. Yield 15.8g (Yield 30%)

[Procedure Amendment 11]

[Document name to be amended] Statement

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(Ii) Synthesis of 5- (3,4-dimethoxybenzylidene) -2-methylthiooxazolin-4-one 5- (3,4-dimethoxybenzylidene) -2-
Thioxo-4-oxazolidinone 15.8 g (0.06
mol) and 8.2 g (0.06 mol) of potassium carbonate, 150 ml of acetonitrile was added, 10.2 g (0.072 mol) of methyl iodide was added dropwise with stirring at room temperature, and the mixture was further stirred at room temperature for 30 minutes. After the reaction was completed, the reaction mixture was poured into 1 liter of water, and the precipitated crystals were collected by filtration and recrystallized with acetone to obtain the desired product. Yield 9.4g (yield 56%)

[Procedure Amendment 12]

[Document name to be amended] Statement

[Correction target item name] 0058

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(Iii) Synthesis of Compound 5 9.4 g (0.038) of 5- (3,4-methoxybenzylidene) -2-methylthiooxazolin-4-one described above.
mol) to which 12% hydrochloric acid (130 ml) was added, and the mixture was heated to 50 ° C. for 30 minutes.
The mixture was heated and stirred for minutes. After the reaction was completed, the precipitated crystals were collected by filtration,
Recrystallized twice with N, N-dimethylformamide,
I got the object. Yield 2.4 g (yield 25%), melting point 288.5 ° C. ¹ H-NMR.

[Procedure Amendment 13]

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Example 3 <Synthesis of Compound 7> (i) 5- (3,4-methylenedioxybenzylidene)
Synthesis of 2-thioxo-4-oxazolidinone 23.8 g (0.159 mol) piperonal, 18.6 g (0.159) 2-thioxo-4-oxazolidinone
mol) and 1.4 g (0.016 mol) of piperidine, 300 ml of ethanol was added, and the mixture was heated under reflux for 2 hours. After cooling to room temperature, the reaction solution was poured into 1 liter of water, the precipitated crude crystals were collected by filtration, and recrystallized with methanol to obtain the desired product. Yield 14.8 g (yield 40%)

[Procedure Amendment 14]

[Document name to be amended] Statement

[Correction target item name] 0063

[Correction method] Change

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(Ii) Synthesis of 5- (3,4-dimethoxybenzylidene) -2-methylthiooxazolin-4-one The above 5- (3,4-methylenedioxybenzylidene)
-2-thioxo-4-oxazolidinone 14.8 g
(0.059 mol, potassium carbonate 8.2 g (0.05
150 ml of acetonitrile was added to 9 mol), and 10.1 g (0.071 m) of methyl iodide was stirred with stirring at room temperature.
ol) was added dropwise, and the mixture was further stirred at room temperature for 30 minutes. After completion of the reaction, the reaction mixture was poured into 1 liter of water, the precipitated crystals were collected by filtration and recrystallized from isopropanol to obtain the desired product. Yield 9.6g (61% yield)

[Procedure Amendment 15]

[Document name to be amended] Statement

[Correction target item name] 0064

[Correction method] Change

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(Iii) Synthesis of Compound 7 The above-mentioned 5- (3,4-methylenedioxybenzylidene)
-2-Methylthiooxazolin-4-one 9.6g
130 ml of 12% hydrochloric acid was added to (0.036 mol) 5
The mixture was heated and stirred at 0 ° C for 30 minutes. After the reaction was completed, the precipitated crystals were collected by filtration and recrystallized with isopropanol to obtain the desired product. Yield 2.4 g (yield 27%), melting point 265.6 ° C. ¹ H-NMR.

Claims (2)

[Claims] 1. A method for producing a 5-benzylideneoxazolidine-2,4-dione derivative represented by the following general formula (I), wherein a 2-thioxo-4-oxazolidinone derivative represented by the following general formula (II) and an aromatic group are used. 5-benzylidene represented by the following general formula (III) from aldehyde
5-Benzylideneoxazolidine-characterized by reacting with an alkyl halide via a 2-thioxo-4-oxazolidinone derivative and then treating with an acid
Process for producing 2,4-dione derivative. General formula (I): General formula (II) General formula (III): 2. A 5-benzylideneoxazolidine-2,4-dione derivative in which R represented by the general formula (I) is a hydrogen atom. (However, Ar is 3,5-di-tert-butyl,
4-hydroxyphenyl and excluding R = H)