JPS5819643B2 - sweet potato - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on the general formula (wherein &ma CH2CH2Cl group, 502CH3 group, C
Represents an OCH3 group, a COC2H5 group or a group.

The present invention relates to a herbicide characterized by containing at least one type of diphenyl ether compound represented by () as five effective acids.

It is a well-known fact that many diphenyl ether compounds have excellent herbicidal activity, for example,
2.4-dichlorophenyl-4-nitrophenyl ether (hereinafter abbreviated as NLP), 2.4.6-trichlorophenyl-4-nitrophenyl ether (hereinafter CN
(abbreviated as P) is widely used as an herbicide for initial use in paddy fields.
Many other diphenyl ether compounds are being investigated for their practical use as herbicides, but these compounds
Slight differences in the chemical structure, such as the type, number, or position of substituents, often result in marked differences in the presence or absence of herbicidal activity, degree, manner of expression, selectivity, and duration of efficacy. It is extremely difficult to predict their herbicidal activity solely by structural similarity.

As a result of synthesizing various diphenyl ether compounds and examining their herbicidal activity, the present inventors found that the compound represented by the above general formula [■] has extremely superior herbicidal properties compared to NIP and CNP. Based on this finding, the present invention was completed.

In other words, the active ingredient compound of the herbicide of the present invention exhibits superior herbicidal activity against barnyard grasses as well as many weeds, compared to NIP or CNP, and also exhibits no reduction in activity due to concentration dilution or chemical damage to paddy rice. It has various excellent herbicidal properties such as extremely small size.

Next, a typical synthesis example of the compound represented by the above general formula [■] will be described.

Synthesis Example 1 Synthesis of 2.4-dichlorophenyl-3-(2-(2-chloroethoxy)ethoxy)-4-nitrophenyl ether (compound 1) 2 (2-(5-chloro-2-nitrophenoxy) ethoxy)ethanol 26.1 y (o, 1 mol) in DM
Potassium-2,4 dichlorophenolate 20. I P (0.1 mol) was added and reacted at 140° C. for 6 hours.

After the reaction was completed, the cooled reaction mixture was discharged into cold water, and the resulting oil was extracted using 100-benzene. The extracted layer was washed with an aqueous sodium hydroxide solution, then with water, and then extracted with anhydrous sodium sulfate. Dehydrated.

Next, 20 grams of thionyl chloride was added to the dehydrated benzene solution, and the mixture was reacted at 60° C. for 2 hours.

After the reaction was completed, water was added to the reaction product to decompose and remove excess thionyl chloride, and the remaining benzene layer was first washed with 5 parts caustic soda, then with water, and further dehydrated with anhydrous sodium sulfate.

Benzene was distilled off from the dehydrated benzene layer under reduced pressure and purified using column chromatography (carrier Nisilica gel, solvent: benzene/n-hexane = 3/2) to obtain a pale yellow oily substance 81 as the purified product of Compound 1. I got it.

(Yield 19.7%) As elemental analysis value C Synthesis of (Compound 2) 2-(5-I'lo-2-nitrophenoxy)ethanol and potassium 2,4-dichlorophenolate 2,4-dichlorophenyl-3-(2-hydroxyethoxy)- 4-nitrophenyl ether 5P (0,01
5 moles) was dissolved in sufficiently dehydrated pyridine 50-, and methanesulfonyl chloride 2.6 f
(0.02 mol) was added and reacted.

Thereafter, the reaction product was stirred at room temperature for 2 hours to complete the reaction, and then discharged into cold water, and the resulting oil was extracted using 50-benzene.

The extract was first washed with aqueous sodium hydroxide solution of 5 parts, then washed with water, and further dehydrated with anhydrous sodium sulfate.

After dehydration, benzene was distilled off from the benzene extract layer under reduced pressure to obtain 5 g of crystals consisting mostly of compound 2 from the residue, which was recrystallized from ethanol to obtain purified product 3. 7f (yield: 58.5%) was obtained.

Elemental analysis value (as C,, H13C12NO7S) (a) Synthesis example 3 Synthesis of 2.4-dichlorophenyl-3-(2-7cetoxyethoxy)-4-nitrophenyl ether (compound 3) 2.4 -dichlorophenyl-3-(2-methoxyethoxy)-4-nitrophenyl ether 10.7f (0,0
3 mol) was dissolved in 50 liters of glacial acetic acid, 20-ml of 48-hydrobromic acid was added thereto, and the mixture was kept at 100°C for 3 hours to react. After the reaction was completed, the reactant was discharged into water to form a product. The resulting oil was extracted using 100% benzene.

The extract was thoroughly washed with water, then dehydrated with anhydrous sodium sulfate, and benzene was distilled off under reduced pressure to obtain crude crystals 11.21 consisting mostly of Compound 3 from the residue.

This was recrystallized from ethanol, m9100-101℃
Purified product 7.11 (yield 63.4%) was obtained.

Elemental analysis value (as C16H13C12N06) Synthesis example 4 2.4-dichlorophenyl-3-(2-phrobiotskijetoxy)-4-nitrophenyl ether (compound 4)
Synthesis of 2.4-il chlorphenyl-3-(2-hydroxyethoxy)-4-nitrophenyl ether 3f(0,0
09 mol) was added to 20rnl of propionic anhydride and reacted at 150°C for 1 hour.

The reaction solution was cooled and discharged into a large amount of water.

Then, granular sodium hydroxide was gradually added to the mixture to decompose and neutralize excess propionic anhydride to obtain milky white crystals.

The crystals were passed through the mouth, washed with cold water, and then recrystallized with ethanol to obtain 2 g of purified compound 4 having a mp of 76 to 77°C.

(Yield 57.5%) Elemental analysis values (C, □H,, C#2N
Synthesis Example 5 2,4-9chlorophenyl-3-(2-benzyloxyethoxy)-4-nitrophenyl ether (compound 5
2. Synthesis of 2.4-bis(2,4-dichlorophenoxy)nitrobenzene g, 9y (o, oz mol), 1.31 g of 86% potassium hydroxide and 20 g of 2-benzyloxyethanol in 100 g of benzene. The mixture was dissolved and reacted at 80°C for 2 hours.

After the reaction is completed, the reaction solution is cooled and 100-g of water is added to make the solution alkaline.The benzene layer is separated, washed with water, dehydrated, and the benzene and excess 2-benzyloxy are separated under reduced pressure. By distilling off the ethanol, most of the compound 5 is
A yellow-brown oil 7.51 was obtained.

This was then subjected to column chromatography (carrier:
Solvent: benzene/chloroform = 3/) to obtain 6.71 of purified compound 5.

(Yield 87%) Elemental analysis value (as C21Hty C12NOs) In the herbicide of the present invention, the active ingredient compound represented by the above general formula [I] may be used as it is, but in general, depending on the purpose of use, Then, it is dissolved or dispersed in a suitable liquid carrier (for example, an organic solvent), or mixed or adsorbed on a suitable solid carrier (for example, a diluent, a filler).

At that time, various auxiliary agents (e.g. emulsifiers, stabilizers, dispersants, suspending agents, spreading agents, wetting agents, penetrating agents) may be added as necessary.
By appropriately adding , it can be used in various dosage forms such as emulsions, wettable powders, granules, and powders.

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

For example, herbicides used in combination with the herbicide of the present invention include:
Urea herbicides, thiol carbamate herbicides, organophosphorus herbicides, acid amide herbicides, triazine herbicides,
There are allyloxy fatty acid herbicides, etc.

The content of the active ingredient of the herbicide of the present invention is 1 to 10 in the case of granules.
For hydrating powders, the ratio is preferably 40 to 80%, and for X emulsions, it is preferably 10 to 50 parts (all parts by weight).

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

In the examples, "parts" represent "parts by weight."

Moreover, the active ingredient compound is represented by the above-mentioned synthetic compound number.

Example 1 16 parts of a granule compound, 70 parts of bentonite, 21 parts of talc, 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 25 parts of granule compound, 70 parts of bentonite, 22 parts of talc, 1 part of sodium lauryl sulfate, and 2 parts of Natsuta and sodium rinsulfonate, an appropriate amount of water was added and kneaded, and the mixture was extruded into a granulator. Granules 1 by the usual method using
Get 00 copies.

Example 3 After mixing 35 parts of granule compound, 50 parts of clay, 44 parts of bentonite, 0.5 part of alkylbenzenesulfonic acid sorter, and 0.5 part of polyvinyl alcohol, an appropriate amount of water was added and kneaded, followed by extrusion granulation. The mixture is granulated using a conventional method using a machine to obtain 100 parts of granules.

Example 4 Irrigation compound 1 50 parts, diatomaceous earth 30 parts, clay 10 parts,
and 10 parts of sodium lauryl sulfate were mixed and ground to obtain 100 parts of an irrigation agent.

Example 5 Emulsion compound 420 parts, Tween-805 parts, Span-805
and 70 parts of solvent naphtha to form an emulsion of 10 parts.
get the part.

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

Test example 1 Field crop weeding test using pre-emergence soil treatment Field air-dried fine (passed through a 14-mesh sieve) 3.
Put 5Kg in a/5000 pot and add N and P to it.
Fertilize the entire layer with chemical fertilizers of 0.52 each of 2O3 and K20,
Adjust soil moisture to the maximum water capacity of 60 g.

A certain amount of seeds of test crops and weeds were sown in this, and after uniformly covering the soil, a predetermined amount of the test compound was added to the above Example 5.
The soil was treated with an emulsion prepared according to the method described in , and grown in a greenhouse.

30 days after seeding, the emergence and growth of crops and weeds were observed and investigated, and the results shown in Table 1 were obtained.

In this table, for the degree of chemical damage to crops and the herbicidal effect on weeds, "0" indicates that the outbreak or growth of crops or weeds is comparable to that in the untreated area, and "0" indicates that the state of crop or weed growth is comparable to that in the untreated plot. 5" and divided into six levels.

Test Example 2 Paddy field initial weeding test Paddy field = Paddy soil where seeds of common weeds are naturally mixed (14
(passed through a mesh sieve) 3.3Kg to a150
Put it in a 00 Wagner pot and add N to it.

P2O, 200.8? After fertilizing the entire layer with chemical fertilizer, add an appropriate amount of water and stir to create a hydrated state.

To this, two paddy rice seedlings (seedlings, leaf age 3.0) that had been previously grown in a greenhouse were used as one plant, and the two plants were transferred and grown in the greenhouse.

Five days after transplanting paddy rice, at the beginning 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.

After treatment 1, the appearance of weeds and the degree of chemical damage to paddy rice were investigated by observation, and the results shown in Table 2 were obtained.

In this table, the display classification of the weed outbreak status is in 6 stages as in Test Example 1, and the display classification of the degree of chemical damage to paddy rice is also "severe damage", "big luck", "medium luck", "small damage", and "slight damage". and"
The rating was set at 6 levels: ``Harmless.''

During the test period, the water depth in the pot was maintained at 3611 cm by hot water treatment at a rate of 1 crrl per day.

Test example 3 Initial weeding of rice fields: field test 3 days after rice planting, 10rr per section? A predetermined amount of the test compound was sprayed onto the stagnant water surface using granules prepared according to the method described in Examples 1 to 3 above.

One month after the treatment, the amount of weeds per unit area in the test plot was measured, and at the same time, phytotoxicity to paddy rice was observed and investigated.

The results are shown in Table 3. In this table, the classification of the degree of chemical damage to paddy rice is the same as in Test Example 2.

As is clear from the above test results, the herbicide of the present invention has a wide herbicidal spectrum, has essentially high herbicidal activity, and is superior to conventional herbicides, such as a decrease in activity due to concentration dilution and less phytotoxicity to crops. It has significantly superior herbicidal properties compared to diphenyl ether herbicides.

[Brief explanation of the drawing]

FIG. 1 shows the infrared absorption spectrum of Compound 1, and FIG. 2 shows the infrared absorption spectrum of Compound 5.

Claims (1)

[Claims] 1 General formula (wherein, Yuma CH2CH2C1 group, 5O2CH3 group, C
Represents 0C2H6 group or. ) A herbicide characterized by containing at least one diphenyl ether compound represented by the following as an active ingredient.