JPH1087663A - Bicyclic hydantoin derivatives, their production method and herbicides containing them as active ingredients - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bicyclic hydantoin derivative having an excellent effect as an active ingredient of a herbicide and a method for producing the same. SOLUTION: General formula (1) The bicyclic hydantoin derivative (1) is obtained by reacting a bicyclic hydantoin derivative represented by the following formula, and an aryl isocyanate derivative represented by the general formula (2) with a pipecolic acid derivative represented by the general formula (3). And a herbicide containing the bicyclic hydantoin derivative as an active ingredient.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel bicyclic hydantoin derivative, a method for producing the same and an intermediate for producing the same, and a herbicide containing the bicyclic hydantoin derivative as an active ingredient.

[0002]

2. Description of the Related Art Hitherto, as bicyclic hydantoin derivatives having herbicidal activity, JP-A-60-233075, JP-A-61-27985, European Patent Publication No. 70389, German Patent Publication No. 3643748, and Japanese Patent Application Laid-Open No. 4-243866, JP-A-4-308591, WO94
05668, WO9522547, JP-A-8-5344
Although the compound described in No. 9 is known, there is a report example on the synthesis of a derivative having a cycloalkyloxy group at the 5-position of the phenyl ring at the 3-position of the hydantoin ring as represented by the general formula (1) of the present invention. Absent.

[0003]

These conventional bicyclic hydantoin derivatives have a poor herbicidal effect on weeds, and those having strong activity have low safety on crops and are not always satisfactory for use as herbicides. Not a compound that can be made. Among them, the compounds described in European Patent Publication No. 70389 or German Patent Publication No. 3643748, as shown in the test examples described below,
Although it has strong herbicidal activity, it has strong phytotoxicity to crops and is not satisfactory for use as a herbicide. The present invention provides a novel bicyclic hydantoin derivative having excellent herbicidal activity and high crop safety, a method for producing the same, and a herbicide containing these derivatives as an active ingredient.

[0004]

Means for Solving the Problems The present inventors have intensively studied for a herbicide having excellent herbicidal activity and crop safety, and as a result, have found that the bicyclic compound represented by the above general formula (1) of the present invention. The present inventors have found that a sex hydantoin derivative exhibits excellent herbicidal activity without application of phytotoxicity to crops and can be applied at a low dose, and have further found a simple production method thereof, thereby completing the present invention.

That is, the present invention provides a compound represented by the general formula (1)

[0006]

Embedded image

(Wherein R represents a cycloalkyl group having 5 to 6 carbon atoms which may be substituted with an alkyl group having 1 to 4 carbon atoms).

Further, the present invention provides a compound represented by the general formula (2):

[0009]

Embedded image

Wherein R represents a cycloalkyl group having 5 to 6 carbon atoms which may be substituted by an alkyl group having 1 to 4 carbon atoms, and a general formula (3)

[0011]

Embedded image

(Wherein R ¹ is a hydrogen atom or a group having 1 to 1 carbon atoms)
6 represents an alkyl group. Wherein the compound is reacted with a pipecolic acid derivative represented by the following general formula (1):

[0013]

Embedded image

(Wherein R has the same meaning as described above.) The present invention relates to a method for producing a bicyclic hydantoin derivative represented by the formula:

Further, the present invention provides a compound of the general formula (4)

Embedded image (Wherein, R represents a cycloalkyl group having 5 to 6 carbon atoms which may be substituted with an alkyl group having 1 to 4 carbon atoms, R ¹
Represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. )
And a urea derivative represented by

Further, the present invention provides a compound represented by the general formula (1):

[0017]

Embedded image

(In the formula, R represents the same meaning as described above.) The present invention relates to a herbicide containing a bicyclic hydantoin derivative represented by the following formula as an active ingredient.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION In the general formulas (1) and (2), examples of the cycloalkyl group having 5 to 6 carbon atoms represented by R include a cyclopentyl group and a cyclohexyl group. Further, these substituents may be substituted by a linear or branched alkyl group having 1 to 4 carbon atoms, and specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, Examples include an isobutyl group and a t-butyl group.

In the general formula (3), the alkyl group having 1 to 6 carbon atoms represented by R ¹ may be linear or branched, and may be a methyl group, an ethyl group, Examples thereof include a propyl group, an isopropyl group, a butyl group, an isobutyl group, a t-butyl group, a pentyl group, and a hexyl group.

The aryl isocyanate derivative represented by the general formula (2), which is a raw material for producing the bicyclic hydantoin derivative represented by the general formula (1) of the present invention, usually contains a corresponding aniline derivative and phosgene or a phosgene equivalent. It can be easily produced by reacting according to the method. The corresponding aniline derivatives are described in, for example,
It can be produced by the method described in JP-A No. 4067, JP-A-5-17411, or JP-A-5-4352, but can also be produced by the method exemplified in Reference Examples described later.

The bicyclic hydantoin derivative of the present invention represented by the general formula (1) is produced by a cycloaddition reaction between an aryl isocyanate derivative (2) and a pipecolic acid derivative (3) as exemplified below. be able to.

[0023]

Embedded image

(Wherein, R and R ¹ have the same meanings as described above)

In the reaction, the amino group of the pipecolic acid derivative (3) is added to the isocyanato group to form a urea derivative (4), and then the amide nitrogen and the ester are cyclized in the molecule to form the bicyclic hydantoin derivative (1). ).
Since the cyclization reaction of the urea derivative (4) is very fast, the bicyclic hydantoin derivative (1) can be obtained in one step without isolating the urea derivative (4).

The addition reaction of the aryl isocyanate derivative (2) with the pipecolic acid derivative (3) does not require any catalyst since the pipecolic acid derivative (3) itself acts as a base. By performing the reaction, the reaction rate can be increased, and the desired product can be obtained in a short time and with high yield. Examples of usable bases include, for example, triethylamine, tributylamine, N
-Organic amines such as methylmorpholine, pyridine, N, N-dimethylaniline, and alkali metals such as potassium carbonate, sodium carbonate, potassium hydrogencarbonate, sodium hydrogencarbonate, sodium hydroxide, potassium hydroxide, sodium hydride, and sodium amide Bases can be exemplified. The amount of the base used is not particularly limited, and the target compound can be obtained in good yield by using 0.001 to 5.0 equivalents to the reaction substrate.

This addition reaction can be carried out without solvent, but it is preferable to use a solvent which does not harm the reaction. Solvents that can be used include, for example, aromatic hydrocarbon solvents such as benzene, toluene, xylene and chlorobenzene, aliphatic hydrocarbon solvents such as hexane, pentane and heptane, diethyl ether, tetrahydrofuran, dioxane and 1,2-dimethoxy Ether solvents such as ethane, halogen solvents such as methylene chloride, chloroform and carbon tetrachloride; ketones such as acetone and methyl ethyl ketone; nitriles such as acetonitrile and propionitrile; alcohol solvents such as methanol, ethanol and cyclohexyl alcohol And esters such as ethyl acetate and propionethyl; amides such as N, N-dimethylformamide and N-methylpyrrolidone; water; or a mixed solvent thereof.

The reaction temperature is selected from the range of -30 to 100 ° C. The urea derivative (4) is easily cyclized to give the hydantoin derivative (1), so that the urea derivative (4) can be obtained in good yield. Although it depends on the reaction conditions, it is generally preferable to carry out the reaction at a low temperature of room temperature or lower. After completion of the reaction, the desired product can be obtained by a usual isolation operation, but if necessary, it can be purified by recrystallization or the like.

The cyclization reaction from the urea derivative (4) to the bicyclic hydantoin derivative (1) can be carried out under either basic or acidic conditions.

The base which can be used in the reaction under basic conditions is exemplified by the above-mentioned production of the urea derivative (4) by the addition reaction of the aryl isocyanate derivative (2) and the pipecolic acid derivative (3). The same bases as described above can be used. The amount of the base used is not particularly limited, and the target compound can be obtained in good yield by using 0.01 to 5.0 equivalents to the reaction substrate.

This cyclization reaction can be carried out without solvent, but it is preferable to use a solvent which does not harm the reaction. Examples of the solvent that can be used include the solvents exemplified in the addition reaction between the aryl isocyanate derivative (2) and the pipecolic acid derivative (3). The reaction temperature is selected from the range of 0 to 150 ° C,
In general, the desired product can be obtained in a high yield by carrying out at a temperature of room temperature to 100 ° C. After completion of the reaction, the desired product can be obtained by a usual extraction operation, but if necessary, it can be purified by column chromatography or the like.

Examples of the acids that can be used in the reaction under acidic conditions include inorganic acids such as hydrochloric acid, sulfuric acid and phosphoric acid, and organic acids such as acetic acid and propionic acid.

This cyclization reaction can be carried out in a solvent that does not harm the reaction, for example, benzene, toluene,
Aromatic hydrocarbon solvents such as xylene and chlorobenzene,
Aliphatic hydrocarbon solvents such as hexane, pentane, heptane, etc., ether solvents such as diethyl ether, tetrahydrofuran, dioxane, 1,2-dimethoxyethane, halogen solvents such as methylene chloride, chloroform, carbon tetrachloride, acetone, methyl ethyl ketone Ketones such as, acetonitrile, nitriles such as propionitrile, N,
Examples include amides such as N-dimethylformamide and N-methylpyrrolidone, water, and a mixed solvent thereof.

The reaction temperature is selected from the range of -30 to 150 ° C., but it is preferable to carry out the reaction at 0 ° C. to the reflux temperature of the solvent to be used in terms of good yield. After completion of the reaction, the desired product can be obtained by a usual extraction operation, but if necessary, it can be purified by column chromatography or the like.

Further, the bicyclic hydantoin derivative (1)
Can be obtained in one step without isolating the urea derivative (4). This cycloaddition reaction can be carried out without using any catalyst, but by carrying out the reaction in the presence of a base, the reaction rate can be increased, and the desired product can be obtained in a short time and with high yield. Examples of usable bases include, for example, organic amines such as triethylamine, tributylamine, N-methylmorpholine, pyridine, N, N-dimethylaniline, potassium carbonate, sodium carbonate, potassium hydrogencarbonate, sodium hydrogencarbonate, sodium hydroxide, Examples thereof include alkali metal bases such as potassium hydroxide, sodium hydride, and sodium amide. The amount of the base used is not particularly limited, and the target compound can be obtained in good yield by using 0.01 to 5.0 equivalents to the reaction substrate.

This cycloaddition reaction can be carried out without a solvent, but it is preferable to use a solvent which does not harm the reaction. Solvents that can be used include, for example, aromatic hydrocarbon solvents such as benzene, toluene, xylene and chlorobenzene, aliphatic hydrocarbon solvents such as hexane, pentane and heptane, diethyl ether, tetrahydrofuran, dioxane and 1,2-dimethoxy Ether solvents such as ethane, halogen solvents such as methylene chloride, chloroform and carbon tetrachloride; ketones such as acetone and methyl ethyl ketone; nitriles such as acetonitrile and propionitrile; esters such as ethyl acetate and propionethyl; Amides such as N, N-dimethylformamide and N-methylpyrrolidone, or a mixed solvent thereof. The reaction temperature is selected from the range of −30 to 150 ° C., but it is preferable to carry out the reaction at 0 to 100 ° C. in terms of good yield. After completion of the reaction, the desired product can be obtained by a usual extraction operation, but if necessary, it can be purified by column chromatography.

The compound of the present invention represented by the general formula (1)
Isomers such as optical isomers or diastereomers exist and are often obtained as a mixture containing all of these isomers. However, each isomer can also be selectively synthesized and separated using various known methods, and the individual isomers as well as mixtures thereof are also included in the present invention.

[0038]

The present invention will be described in more detail with reference to the following examples and reference examples, but the present invention is not limited to these examples.

Example 1

[0040]

Embedded image

A solution of ethyl pipecolate (0.64 mL, 4.07 mmol) in toluene (20 mL) was added to a solution of 4-chloro-5- under ice-cooling and stirring.
Cyclopentyloxy-2-fluorophenyl isocyanate (1.04 g, 4.07 mmol) and triethylamine (0.28
mL, 2.04 mmol) in toluene (10 mL) was added dropwise. 0 ° C
After stirring for 30 minutes at room temperature for 2 hours and at 80 ° C. for 20 hours, potassium carbonate (0.28 g, 2.04 mmol) was added and the mixture was stirred for 100 minutes.
Stirred at 13 ° C. for 13 hours. After completion of the reaction, 1N hydrochloric acid (30 mL) was added, the organic layer was separated, and the aqueous layer was extracted with ethyl acetate (20 mL × 2). Combine the organic layers and add a saturated aqueous sodium chloride solution (8
(0 mL), and dried over anhydrous magnesium sulfate. After the desiccant was filtered off, the filtrate was concentrated under reduced pressure, and the obtained crude product was purified by silica gel column chromatography (Wakogel C-200, ethyl acetate: hexane = 1: 2) to give 2- (4 -Chloro-5-cyclopentyloxy-2-fluorophenyl) -5,6,7,8
-Tetrahydroimidazo [1,5-a] pyridine-1,3 [2
[H, 8aH] -dione (1.14 g, 76.5%) was obtained as a colorless transparent oil.

¹ H-NMR (CDCl ₃ , TMS, ppm): δ1.40 to 1.70
(m, 5H), 1.70-2.00 (m, 7H), 2.00-2.15 (m, 1H), 2.2
5 ~ 2.40 (m, 1H), 2.85 ~ 3.00 (m, 1H), 3.96 (dd, J = 3.97
and 11.4Hz, 1H), 4.20-4.35 (m, 1H), 4.70-4.85 (m,
1H), 6.83 (d, J _HF = 6.49Hz, 1H), 7.25 (d, J _HF = 8.35Hz,
1H).

Embodiment 2

[0044]

Embedded image

A solution of ethyl pipecolate (0.31 mL, 1.99 mmol) in toluene (15 mL) was added to a solution of 4-chloro-2- under ice-cooling and stirring.
A solution of fluoro-5- (3-methylcyclopentyloxy) phenyl isocyanate (488 mg, 1.81 mmol) and triethylamine (0.13 mL, 0.93 mmol) in toluene (5 mL) was added dropwise. After stirring at 0 ° C. for 30 minutes and then at room temperature for 2 hours, potassium carbonate (126 mg, 0.91 mmol) was added and the mixture was stirred at 100 ° C.
For 5 hours. After completion of the reaction, 1N hydrochloric acid (20 mL) was added, the organic layer was separated, and the aqueous layer was extracted with ethyl acetate (20 mL × 2). Combine the organic layers and add a saturated aqueous sodium chloride solution (50 m
L) and dried over anhydrous magnesium sulfate. After the desiccant was filtered off, the filtrate was concentrated under reduced pressure, and the obtained crude product was subjected to silica gel column chromatography (Wakogel®).
C-200, ethyl acetate: hexane = 1: 2) to give 2- [4-chloro-5- (3-methylcyclopentyloxy) -2-fluorophenyl] -5,
6,7,8-tetrahydroimidazo [1,5-a] pyridine-
1,3 [2H, 8aH] -dione (611 mg, 88.7%) was obtained as a pale yellow oil.

¹ H-NMR (CDCl ₃ , TMS, ppm): δ1.02 and 1.
09 (each d, J = 6.55Hz, total 3H), 1.11 ~ 1.22 and 1.3
4 to 1.65 (each m, total 5H), 1.75 to 2.18 (m, 6H), 2.22
〜2.35 (m, 2H), 2.88〜2.97 (m, 1H), 3.96 (dd, J = 3.96 a
nd 11.4Hz, 1H), 4.21-4.29 (m, 1H), 4.68-4.78 (m, 1
H), 6.78 and 6.79 (each d, J _HF = 6.47Hz, total 1H),
7.25 and 7.26 (each d, J _HF = 9.08Hz, total 1H).

Embodiment 3

[0048]

Embedded image

4-chloro-5-cyclopentyloxy-
2-fluorophenyl isocyanate (25.6 g, 0.1 mol)
And triethylamine (0.14 mL, 1 mmol) in ether (70
Ethyl pipecolate (15.7 g,
0.1 mol) was added dropwise over 30 minutes. After the dropwise addition, the mixture was stirred for 1 hour and 45 minutes while gradually raising the temperature from 0 ° C. to room temperature. After completion of the reaction, ether (20 mL) and hexane (70 m
L) was added, and the precipitated solid was collected by filtration. By washing the obtained solid with hexane and drying it sufficiently, N-
[N '-(4-chloro-5-cyclopentyloxy-2
[Fluorophenyl) carbamoyl] ethyl pipecolate (29.2 g, 70.6%) was obtained as a white solid.

MP: 129 to 130 ° C. ¹ H-NMR (CDCl ₃ , TMS, ppm): δ 1.28 (t, J = 7.04 Hz, 3H),
1.50-1.66 (m, 5H), 1.69-1.96 (m, 8H), 2.26-2.34
(m, 1H), 3.29 (dt, J = 3.20 and 12.50Hz, 1H), 3.70〜
3.78 (m, 1H), 4.21 and 4.22 (each q, J = 7.11Hz, total
2H), 4.76 to 4.84 (m, 1H), 5.04 to 5.10 (m, 1H), 6.76 (br
s, 1H), 7.82 (d, J _HF = 10.60Hz, 1H), 7.95 (d, J _HF = 7.56
Hz, 1H) .MS (m / z): 412 (M +, 2.49), 366 (8.64), 298 (100), 271 (5.
60), 235 (6.12), 187 (40.25), 158 (4.43), 84 (92.67),
67 (7.09), 55 (16.86), 41 (23.87), 27 (5.55). Elemental analysis: Calcd. (Calcd. For C ₂₀ H ₂₆ N ₂ O ₄ ClF): C, 58.
18; H, 6.35; N, 6.78. Found: C, 58.19; H, 6.39; H, 6.72%.

Embodiment-4

[0052]

Embedded image

N- [N '-(4-chloro-5-cyclopentyloxy-2-fluorophenyl) carbamoyl]
Ethyl pipecolate (20.7 g, 0.05 mol) in 6N hydrochloric acid (100 m
L) was added and the mixture was heated and stirred at 110 ° C. (oil bath) for 1 hour. After completion of the reaction, toluene (40 mL) was added to the reaction mixture, the organic layer was separated, and the aqueous layer was extracted with toluene (40 mL × 2). Anhydrous magnesium sulfate and a small amount of activated carbon were added to the organic layer, and after drying and decoloring, a desiccant and the like were separated by filtration. The filtrate is concentrated under reduced pressure to give 2- (4-chloro-5-cyclopentyloxy-2-fluorophenyl) -5,6,7,8-.
Tetrahydroimidazo [1,5-a] pyridine-1,3 [2H,
[8aH] -dione (16.0 g, 87.1%) was obtained as a pale brown oil.

Embodiment-5

[0055]

Embedded image

N- [N '-(4-chloro-5-cyclopentyloxy-2-fluorophenyl) carbamoyl]
Ethyl pipecolate (619 mg, 1.5 mmol) and potassium carbonate (1
04 mg, 0.75 mmol) in toluene (10 mL) at 100 ° C. for 5 hours.
The mixture was heated and stirred for hours. After completion of the reaction, the reaction mixture was cooled to room temperature, water (10 mL) was added, the organic layer was separated, and the aqueous layer was extracted with toluene (10 mL × 2). The extracts were combined, washed with saturated saline (20 mL), and dried over anhydrous magnesium sulfate.
The drying agent was filtered off, and the crude product obtained by concentrating the filtrate under reduced pressure was subjected to silica gel column chromatography (Wakogel C-200, ethyl acetate: hexane = 1: 2).
To give 2- (4-chloro-5-cyclopentyloxy-2-fluorophenyl) -5,6,
7,8-tetrahydroimidazo [1,5-a] pyridine-1,
A colorless transparent oil of 3 [2H, 8aH] -dione (513 mg, 93.3%) was obtained.

Reference Example-1

[0058]

Embedded image

A three-neck separable flask (3 L) equipped with a stirrer, a dropping funnel and a reflux condenser was disclosed in
Isobutyl (5-amino-4-chloro-2-fluorophenyl) carbonate (358 g, 1.37 mol) and toluene (750 m) synthesized according to the method exemplified in JP-A-64067.
L) and then ethyl chloroformate (212 g, 1.95 mol) were added at room temperature. The reaction mixture is heated to
% Aqueous sodium hydroxide solution (156 g, 1.95 mol) was added dropwise over 2.5 hours. After the dropwise addition, the mixture was further heated and stirred at 60 ° C. for 5 hours, and then tetrabutylammonium bromide (24.2 g, 0.075 mol) and cyclopentyl bromide (447
g, 3.0 mol) and heated to 100 ° C. Next, 40%
An aqueous sodium hydroxide solution (450 g, 4.5 mol) was added dropwise over 3.5 hours. After the addition, the mixture was further heated and stirred at that temperature for 1 hour. After completion of the reaction, water (500 mL) was added to the reaction mixture, the organic layer was separated, and the aqueous layer was extracted with toluene (500 mL). The obtained organic layers were combined, washed with water (500 mL), and toluene was distilled off under reduced pressure. The resulting residue contains aqueous ethanol.
(77%, 660 mL), and the mixture was heated to 70 to 80 ° C. to form a homogeneous solution, and then left at room temperature. The precipitated crystals were collected by filtration, washed with aqueous ethanol (75%, 500 mL), and sufficiently dried to give ethyl N- (4-chloro-5-cyclopentyloxy-2-fluorophenyl) carbamate (283 g, 62.5%) as white crystals.

MP: 92.8-97.8 ° C. ¹ H-NMR (CDCl ₃ , TMS, ppm): δ 1.33 (t, J = 7.0 Hz, 3H),
1.40-2.10 (m, 8H), 4.32 (q, J = 7.0Hz, 2H), 4.88 (m, 1
H), 6.87 (brs, 1H), 7.15 (d, J _HF = 10.5Hz, 1H), 7.92
(d, J _HF = 7.0Hz, 1H) .IR (KBr disk, cm ^-1 ): 1710, 1535, 1495, 1415, 1255.

Reference Example-2

[0062]

Embedded image

A three-neck separable flask (3 L) equipped with a stirrer, a dropping funnel and a reflux condenser was charged with isobutyl (5-amino-4-chloro-2-fluorophenyl) carbonate (260 g, 0.99 mol) and toluene. (600 mL) and then ethyl chloroformate (141 g, 1.3 mol) were added at room temperature. While heating and stirring the reaction mixture at 60 ° C., a 40% aqueous sodium hydroxide solution (130 g, 1.3 mol) was added dropwise over 2 hours, and the mixture was further stirred for 3 hours. Ethyl chloroformate (32.6 g, 0.3 mol) and 40% aqueous sodium hydroxide solution
(30 g, 0.3 mol) was added, and the mixture was heated and stirred for 2 hours to complete the reaction. Next, tetrabutylammonium bromide (16 g, 0.05 mol) and cyclopentyl bromide (298 g, 2.0 mol) were added to the reaction mixture, and a 40% aqueous sodium hydroxide solution (300 g, 3.0 mol) was added while heating and stirring at 100 ° C. The mixture was added dropwise over 5 hours, and after the addition, stirring was further continued at that temperature for 3 hours. After the reaction, add water (500 mL) to the reaction mixture.
Was added, the organic layer was separated, and the aqueous layer was extracted with toluene (200 mL). The obtained organic layers were combined, washed with water (350 mL), and toluene was distilled off under reduced pressure. Hydrous ethanol (75%, 450 mL) was added to the obtained residue, and 70-
After heating to 80 ° C. to form a homogeneous solution, the solution was allowed to stand at room temperature. The precipitated crystals were collected by filtration and ethanol (75%, 80
0 mL) and thoroughly dried to obtain N- (4
White crystals of ethyl -chloro-5-cyclopentyloxy-2-fluorophenyl) carbamate (185 g, 61.3%) were obtained.

Reference Example-3

[0065]

Embedded image

A 3-neck flask (1 L) equipped with a stirrer, a dropping funnel and a reflux condenser was charged with isobutyl (5-amino-4-chloro-2-fluorophenyl) carbonate (1 L).
31 g, 0.5 mol), toluene (50 mL), and then ethyl chloroformate (70.5 g, 0.65 mol) were added at room temperature. The reaction mixture was
50% aqueous sodium hydroxide solution while heating and stirring at 0 ° C
(52 g, 0.65 mol) was added dropwise over 2.5 hours. After the addition, the mixture was further stirred for 3 hours. Next, tetrabutylammonium bromide (8.06 g, 0.075 mol) and toluene (230 m
L) and a 20% aqueous sodium hydroxide solution (250 g, 1.25 m
ol) was added dropwise at 80 ° C. over 2 hours, and the mixture was further heated and stirred for 8 hours after the addition. Then, the temperature of the reaction mixture was raised to 100 ° C., and cyclopentyl bromide (149 g, 1 mol) was added dropwise over 3 hours. After the dropwise addition, the mixture was further heated and stirred at this temperature for 12 hours. After the reaction, the toluene layer was separated, and water (200 mL) was added.
After washing with, toluene was distilled off under reduced pressure. To the obtained residue, aqueous ethanol (75%, 200 mL) was added, and the mixture was heated to 70 to 80 ° C. while stirring to form a homogeneous solution, and then left at room temperature. The precipitated crystals were collected by filtration, washed with aqueous ethanol (75%, 200 mL), and sufficiently dried to give N- (4-chloro-5-cyclopentyloxy-).
Ethyl 2-fluorophenyl) carbamate (124 g, 82.
3%) of white crystals were obtained.

Reference Example-4

[0068]

Embedded image

A three-necked flask (1 L) equipped with a stirrer, a dropping funnel and a reflux condenser was disclosed in
Ethyl synthesized according to the method exemplified in
Amino-4-chloro-2-fluorophenyl) carbonate (119 g, 0.5 mol), toluene (250 mL), and then ethyl chloroformate (70.5 g, 0.65 mol) were added at room temperature. A 50% aqueous solution of sodium hydroxide (52 g, 0.65 mol) was added dropwise over 1.25 hours while heating and stirring the reaction mixture at 60 ° C.
After the dropwise addition, the mixture was further heated and stirred at 80 ° C. for 6 hours. Tetrabutylammonium bromide (8.1 g, 0.025 mol) in the reaction mixture
And cyclopentyl bromide (149 g, 1.0 mol), and 10
40% aqueous sodium hydroxide solution while heating and stirring at 0 ° C
(150 g, 1.5 mol) was added dropwise over 3 hours. After the addition, the mixture was further heated and stirred at that temperature for 2 hours. After completion of the reaction, water (100 mL) was added to the reaction mixture, the organic layer was separated, and the aqueous layer was diluted with toluene (10 mL).
0 mL). Combine the obtained organic layers and add water (200 mL)
After washing with, toluene was distilled off under reduced pressure. Aqueous ethanol (75%, 200 mL) was added to the obtained residue, and the mixture was heated at 70 to 80 ° C. with stirring to form a homogeneous solution, and the solution was allowed to stand at room temperature. The precipitated crystals were collected by filtration and washed with aqueous ethanol (7.
5%, 200 mL) and thoroughly dried to obtain N
White crystals of ethyl-(4-chloro-5-cyclopentyloxy-2-fluorophenyl) carbamate (112 g, 74.2%) were obtained.

Reference Example-5

[0071]

Embedded image

Ethyl N- (4-chloro-5-cyclopentyloxy-2-fluorophenyl) carbamate (12.
7 g, 42.1 mmol), ethyl alcohol (50 mL) and 2N-
A mixed solution of sodium hydroxide aqueous solution (100 mL) is heated at 110 ° C.
For 4 hours. After completion of the reaction, the solvent was distilled off under reduced pressure, water (100 mL) was added, and the mixture was extracted with ethyl acetate (100 mL × 3). The organic layer was washed with brine and dried over anhydrous magnesium sulfate. The drying agent was removed by filtration, and the filtrate was concentrated under reduced pressure to obtain a colorless, transparent oil of 4-chloro-5-cyclopentyloxy-2-fluoroaniline (9.36 g, 96.8%).

BP: 143 to 145 ° C./1.5 mmHg ¹ H-NMR (CDCl ₃ , TMS, ppm): δ 1.40 to 2.00 (m, 8H), 3.72
(brs, 2H), 4.67 (m, 1H), 6.39 (d, J _HF = 9.0Hz, 1H), 7.
04 (d, J _HF = 11.0Hz, 1H). IR (neat, cm ^-1 ): 3500, 3400, 1630, 1510, 1420, 1245,
1185.

Reference Example-6

[0075]

Embedded image

Trichloromethyl chloroformate (15 mL, 0.123
mol) in toluene (50 mL), 4-chloro-5-cyclopentyloxy-2-fluoroaniline (23.0 g, 0.10 mol
l) and a solution of triethylamine (0.5 mL) in toluene (50 mL) were added dropwise with stirring under ice cooling. The reaction mixture was further stirred for 1 hour under ice cooling, and then heated to room temperature. Next, the obtained reaction mixture was heated and stirred at 100 to 110 ° C. until generation of gas (hydrochloric acid gas, phosgene gas, and the like) stopped. After the completion of the reaction, toluene was distilled off under reduced pressure, whereby a brown oil of 4-chloro-5-cyclopentyloxy-2-fluorophenylisocyanate could be obtained almost quantitatively.

¹ H-NMR (CDCl ₃ , TMS, ppm): δ1.50-2.10
(m, 8H), 4.67 (m, 1H), 6.60 (d, J _HF = 7.5Hz, 1H), 7.12
(d, J _HF = 10.5Hz, 1H). IR (neat, cm ^-1 ): 2275, 1720, 1615, 1525, 1470, 1195.

Next, the compounds of the present invention synthesized by the methods exemplified in the above Examples are shown in Tables including the compounds shown in the Examples.
1 and Table 2, but the present invention is not limited to these.

[0079]

[Table 1]

[0080]

[Table 2]

When the compound of the present invention is used as a herbicide, it can be used as it is, but in general, one or several adjuvants can be mixed and used as a herbicide. Usually, as an auxiliary, various carriers, extenders, solvents,
It is preferable that a surfactant, a stabilizer, and the like are blended and formulated into a form such as a wettable powder, an emulsion, a powder, a granule, a flowable and the like by a conventional method.

Examples of the solvent which is one of the adjuvants in the herbicide containing the compound of the present invention as an active ingredient include water, alcohols, ketones, ethers, aliphatic and aromatic hydrocarbons, and halogenated hydrocarbons. Suitable are hydrogens, acid amides, esters, nitriles, etc., and one or a mixture of two or more of these are used.

Examples of the extender include clays such as kaolin and bentonite; talcs such as talc and pyrophyllite; diatomaceous earth;
Mineral powders such as oxides such as white carbon and vegetable powders such as soybean powder and CMC are used. Further, a surfactant may be used as a spreading agent, a dispersant, an emulsifier, or a penetrant. Examples of the surfactant include a nonionic surfactant, a cationic surfactant, an amphoteric surfactant, and the like. These surfactants are utilized as one kind or a mixture of two or more kinds depending on the use.

Preferred methods of using the herbicide containing the compound of the present invention as an active ingredient include soil treatment, water surface treatment, foliage treatment, and the like. Can be mentioned.

The herbicide containing the compound of the present invention as an active ingredient may be any other active ingredient which does not inhibit the herbicidal activity of the active ingredient, such as other herbicides, insecticides, fungicides, plant growth regulators. It is also possible to mix and use the agents and the like or to use them in combination.

Next, the present invention will be described in more detail with reference to preparation examples of herbicides containing the compound of the present invention as an active ingredient and examples in which the herbicidal effect of the present herbicide has been studied. The parts are by weight.

Formulation Example 1 (Emulsion) 20 parts of the compound of the present invention, 35 parts of xylene, 40 parts of cyclohexanone, and 5 parts of Solbol 900A (manufactured by Toho Chemical) were uniformly mixed to obtain an emulsion.

Formulation Example-2 (Wettable powder) 50 parts of the compound of the present invention, 25 parts of diatomaceous earth, 22 parts of clay,
A mixture of 3 parts of Lunox R100C (manufactured by Toho Chemical Co., Ltd.) was uniformly mixed and pulverized to obtain a wettable powder.

Formulation Example-3 (granules) 5 parts of the compound of the present invention, 35 parts of bentonite, talc 55
Parts and a mixture of 5 parts of sodium ligninsulfonate were uniformly mixed and pulverized, kneaded by adding water, granulated by an extrusion granulator, dried and sized to obtain granules.

The herbicidal effects of the compounds of the present invention were investigated in accordance with the methods shown in the following Test Examples, using the preparations prepared according to the methods exemplified above. The herbicidal effect on the test weeds and the phytotoxicity on the test crops were determined according to the criteria shown in Table-3.

[0091]

[Table 3]

As a control compound, the following comparative drug A was used in each test, and the results were shown in the table based on the same criteria.

[0093]

Embedded image

Test Example 1 (Effects on Paddy Field Weeds) A 1 / 10,000 are pot was filled with paddy field soil, and after shaving, seeds of Aedes spp., Tamagayatsuri, Konagi, Firefly, Pine tree, and other annual broadleaf weeds were placed therein. The rice was sown and transplanted with rice (cultivar: Koshihikari) at the 2.5 leaf stage and kept in a irrigated state. One day later, the wettable powder or emulsion of the compound of the present invention prepared according to Formulation Examples was diluted and processed to give a predetermined dose per are. 15 days after the treatment, the herbicidal effect on the test weeds and the phytotoxicity on the rice 1
Investigation was carried out using up to five criteria, and the results are shown in Table-4.

[0095]

[Table 4]

Test Example-2 (Effect of Field Soil Treatment) A bat having an area of 10 × 10 cm ² and a depth of 5 cm was filled with field soil, and seeds of dog millet, mehisiba, aoubiyu, shiroza and corn were sowed, and 0.5c on top
m of soil. The next day, the wettable powder or emulsion of the compound of the present invention prepared in accordance with the formulation example was diluted and uniformly spread on the covering soil so as to have a predetermined dose per are. 15 days after the treatment, the herbicidal effect on the test weeds and the phytotoxicity on corn were investigated using 1 to 5 levels of criteria,
Table 5 shows the results.

[0097]

[Table 5]

[0098]

The bicyclic hydantoin derivative of the present invention is
It has excellent herbicidal activity and high crop safety, and is useful as a herbicide. Further, these derivatives can be easily produced by the production method of the present invention via the urea derivative of the present invention.

Continued on the front page (72) Inventor Tomoyuki Yano 1-9-1, Minamidai, Sagamihara City, Kanagawa Prefecture (72) Inventor Kazuhisa 1-22-20 Bunkyo, Sagamihara City, Kanagawa Prefecture (72) Inventor Tomoko Yoshii Tanaka, Fujieda City, Shizuoka Prefecture 3-7-9 (72) Inventor Sadayuki Ukai 4-5-12, Minamisurugadai, Fujieda-shi, Shizuoka Prefecture (72) Inventor Osamu Yamada 1-1-16-21 Takasu, Mihama-ku, Chiba-shi, Chiba Prefecture (72) Inventor Takuya Ueda Shizuoka, Shizuoka 2-14-12 Onishi-cho, Fujieda-shi

Claims (4)

[Claims] 1. A compound of the general formula (1) (In the formula, R represents a cycloalkyl group having 5 to 6 carbon atoms which may be substituted with an alkyl group having 1 to 4 carbon atoms.) 2. A compound of the general formula (2) (Wherein, R represents a cycloalkyl group having 5 to 6 carbon atoms which may be substituted with an alkyl group having 1 to 4 carbon atoms), and an aryl isocyanate derivative represented by the following general formula (3): ] (Wherein, R ¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms), characterized by reacting with a pipecolic acid derivative represented by the following general formula (1): (In the formula, R represents a cycloalkyl group having 5 to 6 carbon atoms which may be substituted with an alkyl group having 1 to 4 carbon atoms.) A method for producing a bicyclic hydantoin derivative represented by the formula: 3. A compound of the general formula (4) (Wherein, R represents a cycloalkyl group having 5 to 6 carbon atoms which may be substituted with an alkyl group having 1 to 4 carbon atoms, R ¹
Represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. )
A urea derivative represented by the formula: 4. A compound of the general formula (1) In the formula, R represents a cycloalkyl group having 5 to 6 carbon atoms which may be substituted with an alkyl group having 1 to 4 carbon atoms. A) a herbicide comprising, as an active ingredient, a bicyclic hydantoin derivative represented by the following formula: