JPS5827243B2 - Satsovzai - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on the general formula (wherein R represents a lower alkyl group, X represents a chlorine atom or a fluorine atom, and m represents an integer of 0 to 2, where n represents an integer of O to 2).

The present invention relates to a herbicide characterized by containing at least one diphenyl ether compound represented by () as an active ingredient.

It is a well-known fact that certain types of diphenyl ether compounds have excellent herbicidal properties, such as 2,4-dichlorophenyl-4-nitrophenyl ether (hereinafter abbreviated as NLP).

) and 2,4,6-dolychlorphenyl-4-nitrophenyl ether (hereinafter abbreviated as GNP) are widely used as herbicides for initial use in rice fields, and many other diphenyl ether compounds are also used as herbicides. The practicality of these compounds is being studied, but the types of substituents,
Slight differences in chemical structure, such as number or position, often result in significant differences in the presence or absence of herbicidal activity, extent, mode of expression, selectivity, and duration of efficacy. It is extremely difficult to predict the herbicidal activity of these compounds.

The present inventors synthesized various new diphenyl ether compounds and examined their herbicidal activity. As a result, the above general formula [
It was discovered that the compound represented by (2) has extremely superior herbicidal properties compared to NIP and CNP, and based on this fact, the present invention was completed.

That is, the general formula [■] which is the active ingredient of the herbicide of the present invention
Compared to NIP or CNP, this compound exhibits superior herbicidal activity against many weeds as well as beetles, and its herbicidal activity does not decrease due to concentration dilution, and the chemical damage to paddy rice and other useful crops is extremely small. It has various excellent herbicidal properties.

Next, a typical synthesis example of the compound represented by the general formula CI) will be described.

Synthesis Example I Synthesis of 2-chloro-4-methylthiophenyl-3-(2-fluoroethoxy)-4-nitrophenyl ether (compound 1)* 2,4-bis(2-chloro-4-methylthiophenoxy)nitrobenzene 86% potassium hydroxide 2f (0.03 mol) was added to a solution of 9.4 P (0.02 mol) dissolved in 50 ml of dioxane, and while stirring, 2-fluoroethanol 2P (0.03 mol) was dissolved at 20°C. mol) dropwise.

The reaction solution was heated to 35° C., stirred at the same temperature for 1 hour, and then drained into 200 ml of cold water, and the resulting yellow-brown oil was extracted with shaking using 50 ml of benzene.

This extract was washed with a 10% aqueous sodium hydroxide solution and then with water, the benzene layer was dehydrated with anhydrous sodium sulfate, and the benzene was distilled off under reduced pressure to obtain the crystalline yellow-brown substance 7i. Recrystallized from ethanol, melting point 98-9
2-chloro-4=methylthiophenyl-3-(2
-fluorethoxy)-4-nitrophenyl ether 6
．． Get 1y.

(Yield 85.3%) Elemental analysis value (%) C15H13
Synthesis example 2 2-chloro-4-methylsulfinylphenyl 3-(2
-fluorethoxy)-4-nitrophenyl ether (
Synthesis of Compound 2) Chlormethylthiophenyl-(fluoroethoxy)-4 nitrophenyl ether (Compound 1) 3.6P (0.01 mol) was added to 50 ml of glacial acetic acid, and 3.6P (0.01 mol) was added to this at 10°C or below.
After dropping 1.21 g of 5% hydrogen peroxide, the temperature was raised to 20°C,
Stir for 2 hours to react.

This reaction solution was allowed to stand for a day and night, then drained into 20 Qml of water, and the resulting yellowish-brown oil was extracted using 50ml of benzene.

The extracted benzene layer was washed with water, dehydrated with anhydrous sodium sulfate, and the benzene was distilled off under reduced pressure. The resulting crystalline pale yellow substance 3.41 was recrystallized from ethanol to give a melting point of 93~
2-chloro-4-1-tylsulfinylphenyl-3-(2-fluoroethoxy)-4-nitrophenyl ether 21 is obtained at 94.5°C.

Synthesis example 3 2-chloro-4-methylsulfonylphenyl 3-(2-
Synthesis of fluoroethoxy)-4-nitrophenyl ether (compound 3) 2J lo-4-methylthiophenyl-3 (2-fluoroethoxy)-4-nitrophenyl ether (compound 1) 3.6f (0.01 mol ) was added to 50 mg of glacial acetic acid, and 2.51 g of 35% hydrogen peroxide solution was added dropwise at 10°C or below, then the temperature was raised to 90°C, and the mixture was stirred at the same temperature for 2 hours to react.

The reaction solution was cooled to room temperature and then drained into 200 ml of water, and the resulting yellow-brown oil was extracted with 50 ml of benzene.

The extracted benzene layer was washed with water and then dehydrated with anhydrous sodium sulfate, and the benzene was distilled off under reduced pressure to obtain a crystalline pale yellow substance with a melting point of 123-123. 2-chloro-4-methylsulfonylphenyl-3-(2-fluoroethoxy)4-nitrophenyl ether at 5°C 3.4? I got it.

(Yield 87.2%) Elemental analysis value (%) as CI5H13CIFNO3 Synthesis example 4 2-chloro-4-methylthiophenyl-3(2-chloroethoxy)-4-nitrophenyl ether (compound 4)
Synthesis of 2-chloro-4-methylthiophenyl-3-hydroxy-4-nitrophenyl ether 6.2f (0.02 mol) and 1-bromo-2-chloroethane 7f (0.05 mol) were dissolved in DMF50rrLl. Then, anhydrous potassium carbonate 3P (0,022 mol) was added and the mixture was heated at 80°C.
Stir and react for some time.

The reaction solution was cooled to room temperature and then drained into 20011 L of water, and the resulting yellowish-brown oil was extracted by shaking using 50 rrL of benzene.

This extracted benzene layer was washed with a 10% aqueous sodium hydroxide solution, then water, then dehydrated with anhydrous sodium sulfate, and the benzene was distilled off under reduced pressure to obtain a yellow crystalline substance 6.
．． 11 was recrystallized from ethanol, melting point 86-87℃.
5.31 of 2-chloro-4-methylthiophenyl-3(2-chloroethoxy)-4-nitrophenyl ether is obtained.

(Yield 70.7%) Elemental analysis value (%) C,,H13C1°N04S Compounds other than those mentioned above which are active ingredients of the herbicide of the present invention can also be synthesized according to the method of the above synthesis example.

Table 1* shows representative examples and physical properties of these compounds.

In the herbicide of the present invention, the active ingredient compound represented by general formula CI) may be used as it is, but in general, depending on the purpose of use, it may be carried in a suitable liquid carrier (for example, an organic liquid).
or mixed or adsorbed onto a suitable solid carrier (e.g. diluent, filler).

At that time, by adding various auxiliary agents (e.g. emulsifiers, stabilizers, dispersants, suspending agents, spreading agents, wetting agents, penetrating agents) as necessary, emulsions, hydrating agents, granules, etc. It can be used in various dosage forms such as powders and powders.

The herbicide of the present invention includes one or more other herbicides,
Not only can it be used in combination with agricultural chemicals such as insecticides, fungicides, and plant growth regulators, soil conditioners, or fertilizing substances, but also mixed formulations with these agents are possible.

For example, herbicides used in combination with the herbicide of the present invention include:
These include urea-based herbicides, thiol carbamate-based herbicides, organophosphorus-based herbicides, acid amide-based herbicides, triazine-based herbicides, and allyloxy fatty acid-based herbicides.

The content of the active ingredient of the herbicide of the present invention is 1 to 10 in the case of granules.
%, 40-80% for aqueous phase agents, 10-50% for emulsions (
All percentages are by weight.

) is desirable.

Next, Examples of the herbicide of the present invention will be shown.

"Parts" in the examples represent "parts by weight."

In addition, the active ingredient compounds are shown in Table 1 and by the compound number of the synthesis example.

Example 1 14 parts of a granule compound, 73 parts of bentonite, 20 parts of Merck, 2 parts of sodium dodecylbenzenesulfonate, and 1 part of sodium ligninsulfonate were mixed, and an appropriate amount of water was added and kneaded, followed by an extrusion granulator. The mixture is granulated using a conventional method to obtain 100 parts of granules.

Example 2 After mixing 21 parts of a granule compound, 80 parts of Bentonai, 17 parts of Merck, 11 parts of polyoxyethylene glycol monomer, and 1 part of sodium naphthalene sulfonate, an appropriate amount of water was added, kneaded, and extruded. The mixture is granulated in a conventional manner using a granulator to obtain 100 parts of granules.

Example 3 350 parts of hydrating agent compound, 40 parts of Merck, 7 parts of sodium lauryl sulfate
1 part and 3 parts of sodium alkylnaphthalene sulfonate are mixed and ground to obtain 100 parts of a wettable powder.

Example 4 50 parts of water phase agent compound 7, 40 parts of diatomaceous matter, and 10 parts of sodium dodecylbenzenesulfonate were mixed and ground to obtain 100 parts of water phase agent.

Example 5 1010 parts of an emulsion compound, 10 parts of Tsurupol 800A (emulsifier manufactured by Toho Kagaku ■), and 80 parts of flubento naphtha are mixed to obtain 100 parts of an emulsion.

Next, the effects of the herbicide of the present invention will be specifically explained using test examples.

Test example 1 Field crop weeding test by pre-emergence soil treatment Field air-dried fine soil (passed through a 14-mesh sieve)3.
5 kg was placed in an A/5000 Wagner pot, and 11 parts each of N, P2O5, and K20 were applied to the entire layer with chemical fertilizers to bring the soil moisture to 60% of the maximum water capacity, and a certain amount of seeds of the test plants were added to the pot. Seed and cover with soil.

The test compound was prepared into an emulsion according to the method of Example 5, a predetermined amount of the emulsion was diluted in water equivalent to 101/a, and the soil in the pot was uniformly treated with a pipette, and then the emulsion was placed in a greenhouse. They were left behind to grow crops.

One month after the treatment, germination and growth conditions of crops and weeds were observed and investigated.

The results are shown in Table 2. In this table, "0" indicates that there is no or almost no difference in the germination, growth, or emergence of crops or weeds compared to those in the untreated area.
'', those whose growth was completely suppressed were given a ``5'', and those in between were classified into 6 levels and displayed.

Test Example 2 Paddy field initial weeding test Paddy field soil (14
(passed through a mesh sieve) 3.3 kg a/
Put it in a 5000 sogenel pot and add NP2O5 and K to it.
After fertilizing the entire layer with a chemical fertilizer of 0.81 each of 20, add an appropriate amount of water and stir to create a hydrated state.

To this, two rice seedlings (sterile bacteria, leaf age 3.0) grown in advance in a greenhouse were used as one plant, and the two plants were transplanted and grown in the greenhouse.

Five days after rice transplantation, at the onset of weed emergence, a predetermined amount of the test compound was treated under swamping using granules prepared according to the method described in Examples 1 to 3 above.

One month after the treatment, the appearance of weeds and the degree of chemical damage to paddy rice were investigated by observation, and the results shown in Table 3 were obtained.

In this table, the display classification of the state of weed growth is set to 6 levels, similar to the test sample plant, and the display classification of the degree of chemical damage to paddy rice is ``severe damage'', ``big luck'', ``perishing damage'', ``small book'', and ``slightly scented''. "and"
The rating was set at 6 levels: ``Harmless.''

During the test period, the water leakage depth of the pot was maintained at 3 crfL by treating water leakage at a rate of 1 cIrL per day.

Test Example 3 Initial weeding in a rice field is a field test.The rice field 5 days after rice planting was divided into 10-10 plots. *1 One month after spraying,
The amount of weeds per meter in the test plot and the chemical damage to paddy rice were observed and investigated, and the results shown in Table 4 were obtained.

In this table, the indication of the degree of chemical damage to paddy rice is the same as in Test Example 2.

[Brief explanation of the drawing]

FIG. 1 shows an infrared absorption spectrum diagram of Compound 20.

Claims (1)

[Claims] (In the formula, R represents a lower alkyl group, X represents a chlorine atom or a fluorine atom, m represents an integer of O to 2, and n represents an integer of O to 2, and X may be different or the same. A herbicide characterized by containing at least one type of diphenyl ether compound represented by () as an active ingredient.